Skip to contentUnited States Department of Transportation - Federal Highway Administration FHWA Home
Research Home   |   Pavements Home
Report
This report is an archived publication and may contain dated technical, contact, and link information
Publication Number: FHWA-RD-07-052
Date: September 2007

Long Term Pavement Performance Project Laboratory Materials Testing and Handling Guide

Chapter 4 Testing Instructions

4.3 Standard Codes

This last section of Chapter 4 contains the detail information on the codes used in completing the laboratory test data sheets. These include the comment codes used at the bottom of the test data sheets. One or more of the LTPP standard comments presented in Table 4.24 may have been used on the test form. Some of the comments presented in Table 4.24 are specific to particular protocols. The relevant protocols for each comment are provided within the table.

Table 4.24 LTPP Standard Comments
COMMENT CODE LTPP STANDARD COMMENT RELEVANT TO PROTOCOL
01 Test is performed on insufficient size sample according to the test standard/protocol. All
02 The test specimen is flawed, not ideal, still tested. All
03 Procedural mistake is made by the laboratory or the laboratory suspects that some test parts were not in strict conformance to the protocol. All
04 Test results (partially) do not seem reasonable; no explanation is provided. All
05 Test results (partially) do not seem reasonable; explanation is provided in the following note. All
06 Test is suspect, sample was misnumbered. All
07 Test is suspect, sample was not correctly identified. All
08 Equipment was not in calibration (found after inspection). All
09 L/D (specimen length to diameter) ratio is not according to the requirement of the test for layer thickness. All
10 L/D ratio is not according to the requirement for maximum size aggregate. All
11 The technician's results are not consistent with the previous technician's results. All
12 This test is a replacement for the previous test. All
13 LTPP has directed a deviation in the test procedure. All
14 Substantial update in the LTPP protocol. All
15 Very thin, untestable, layer. All
16 Layer thickness was measured in the laboratory prior to sawing from other bonded layers. All
17 Layer thickness was not measured in the laboratory prior to sawing from other bonded layers. All
18 Insufficient material to perform the test. Test was not performed. All

19

Insufficient material to perform the moisture content test. Test was not performed.

All

20

Not enough AC for H03L/H04L on separate samples. H03L sample reused for the H04L test.

All

21

Length to diameter ratio was less than 1.0 because the layer thickness was less than the diameter of the specimen.

P61

22

Length to diameter ratio was equal to or less than 1.0 because the specimen was sawed in order to remove concrete with embedded steel.

P61

23

Embedded steel was noted in the specimen near the middle of the diametral plane.

P61

24

Embedded steel was noted at or near the side of the test specimen.

P61

25

The specimen was skewed (either end of the specimen departed from perpendicularity to the axis by more than 0.5° or 1/8 inch in 12 inches (3 mm in 305 mm), as tested by placing the specimen on a level surface).

P61

26

Mr determinations generally done within four minutes.

All

27

Mr determinations were generally not done within four minutes.

All

28

Test performed in a temperature controlled cabinet.

All

29

Dummy specimen used to monitor temperature.

All

30

Specimen damaged and not tested. Replacement was used.

All

31

Length to diameter ratio was equal to or less than 1.0 because the layer thickness was less than the diameter of the specimen.

P62

32

The specimen was trimmed only at the bottom end.

P62

33

The specimen was trimmed only at the top end.

P62

34

The specimen was trimmed at the bottom and top ends.

P62

35

The line of contact between the specimen and each bearing strip was straight and free from any projections or depressions higher or deeper than 0.01 inches (0.25 mm).

P62

36

The line of contact described in code 35 above was made possible by grinding.

P62

37

The line of contact described in code 35 above was made possible by capping, or by grinding and capping.

P62

38

The line of contact between the specimen and each bearing strip had more than 0.01-inch (0.25-mm) tolerance as described in Code 35 but less than 0.1-inch (2.5-mm) tolerance. The specimen was tested.

P62

39

The projections/depressions on the test surface (as described in Code 35) were higher or deeper than 0.1 inch (2.5 mm). The specimen was tested because there was no other replacement specimen.

P62

40

The PCC core retrieved from the field did not have any arrow or "T" to show the direction of traffic.

P62

41

Length to diameter ratio was less than 1.5 because the layer was equal to or less than the diameter of the specimen.

P64

42

Length to diameter ratio was equal to or less than 1.5 because the specimen was sawed in order to remove concrete with embedded steel.

P64

43

Embedded steel was noted in the specimen near the middle of the diametral plane.

P64

44

Embedded steel was noted at or near the side of the test specimen.

P64

45

The specimen was trimmed only at the bottom end.

P64

46

The specimen was trimmed only at the top end.

P64

47

The specimen was trimmed at the top and bottom ends.

P64

48

Percent smaller than 0.001 mm (0.04 mils) could not be determined in 1440 minutes (24 hours).

P42

50

Specimen capped

P69

51

Specimen ground

P69

52

Leather shims used

P69

53

Irregular interface between existing and overlay concrete.

P67

54

Failure plane in overlay concrete.

P67

55

Failure plane in existing concrete.

P67

56

Failure plane in interface between existing and overlay concrete.

P67

61

Insufficient size of test sample because the quantity of the bulk sample was significantly less than that required for the tests.

P14A, P41, P44, P47, P51, P51A, P52, P55

62

Presence of roots and other organic matter in the bulk sample retrieved from the field.

P41, P44, P47, P51, P51A, P52, P55

63

Presence of mica in the bulk sample retrieved from the field.

P41, P44, P47, P51, P51A, P52, P55

64

The bulk sample contained cobbles or large size aggregates (stone fragments passing the 12-in. [305-mm] sieve and retained on the 3-in. [76-mm] size sieve).

P41, P44, P47, P51, P51A, P52, P55

65

The test sample included shale chunks, claystone, mudstone, siltstone, and sandstone which convert into soils after field and/or laboratory processing (crushing, slacking, etc.).

P41, P44, P47, P51, P51A, P52, P55

67

PI reported as 'NP' because the LL and/or PL cannot be determined.

P43

68

PI is reported as 'NP' because the PL is equal to or greater than the LL.

P43

69

The test specimen slipped in the cup of the LL device.

P43

70

Test could not be completed within five water addition increments. Additional increments were made.

P44, P55

71

Degradation of the test sample was observed during the moisture-density test.

P44, P55

72

The quantity of the test sample was inadequate to complete the moisture-density test. Additional quantity was taken from other test samples or extra material to complete the moisture-density test.

P44, P55

73

Free water appeared at the bottom of the mold (i.e., seeped onto the place).

P44, P55

74

The gradation test results (Protocol P41 and Form T41 or Protocol P51 and Form T51, as appropriate) indicate up to 5% coarse material passing the 1 ½-in. (38-mm) sieve and retained on the No. 4 (4.75-mm) sieve. This coarse fraction was included in the test sample for the moisture-density test.

P44, P55

75

The coarse fraction passing the 1 ½ in. (38-mm) sieve and retained on the No. 4 (4.75-mm) sieve was more than 5%. Method D was used to perform the moisture-density test.

P44, P55

76

The test sample contained coarse material larger than the 1 ½ in. (38-mm) sieve. This coarse material was removed and not used for the moisture-density test.

P44, P55

77

The gradation test results (Protocol P41 and Form T41 or Protocol P51 and Form T51, as appropriate) indicate up to 5% coarse material passing the 1 ½-in. (38-mm) sieve and retained on the ¾-in. (19-mm) sieve. This coarse material was included in the test sample for the moisture-density test.

P44, P55

78

The coarse fraction passing the 1 ½-in. (38-mm) sieve and retained on the ¾-in. (19-mm) sieve was more than 5%. The test sample for the moisture-density testing was sieved using a ¾-in. (19-mm) sieve to separate the coarse fraction from the test sample. This coarse fraction was discarded from the test sample and not used in the moisture-density test.

The test sample was, therefore, not truly representative of the bulk sample.

P44, P55

80

Due to insufficient size of the bulk sample, the test sample was used for the last test (Protocol P46, if the sample was reconstituted was saved and stored for possible future use by the LTPP program.

P46

81

A seperate test sample was used for classification and description tests (Protocols P46 or P52)

P46

82

Due to the insufficient size of the bulk sample, the test sample for the gradation test (Protocol P41 or P51) was also used to complete the classification and description tests. (Protocol P47 or P52)

P46

83

Due to the insufficient size of the bulk sample, the test sample for the moisture-density test (Protocol P44 or P55) was saved after the test and reused for the resilient modulus testing (Protocol P46).

P44, P46, P55

84

Due to insufficient size of the bulk sample; the sample for the moisture-density testing was obtained from the gradation test sample. The gradation test (Protocol P41 or P51) was performed by dry sieving only.

P44, P55

85

Due to the insufficient size of the bulk sample, only dry sieving was used for the gradation test (Protocol P41 or P51). The test sample after the gradation test was saved and reused to reconstitute the test sample of the resilient modulus testing (Protocol P46).

P46

86

Due to the insufficient size of the bulk sample, only dry sieving was used for the gradation test (Protocol P41 or P51). The test sample was reused for other designated tests and the remnant of the sample was saved and stored for possible future use by the LTPP program.

P46

87

The "undisturbed" thin-wall tube sample was used for the resilient modulus testing (Protocol P46).

P46

88

The thin-wall tube sample was not suitable, therefore a reconstituted sample from the bulk samples was used for the resilient modulus testing.

P46

89

The thin-wall tube sample was not available. The test sample for the resilient modulus testing (Protocol P46) was reconstituted from the bulk sample.

P46

90

An excess portion of the thin-wall tube sample was saved and stored for possible future use by the LTPP program.

P46

91

The thickness of the treated layer was determined in the laboratory using the intact cores and the Protocol P31 procedure. Compressive strength test (Protocol P32 for OTB materials) or resilient modulus test (Protocol P07 for ATB materials) shall not be performed on the cores from the designated locations, because the thickness is less than 3 inches (76 mm) or 1 inch (25 mm), respectively.

P31, P32

92

Intact cores were not available. The thickness of the treated layer was averaged from the information available on field exploration logs and used as is in reporting the test results of Protocol P31 on Form T31. Only the Protocol P31 test was conducted on chunks and pieces. Compressive strength test on OTB materials (Protocol P32) or resilient modulus test on ATB materials (Protocol P07) shall not be performed.

P31, P32

93

The thickness of the treated layer was 3 inches (76 mm) (Protocol P32) or 1 inch (25 mm) (Protocol P07) or more as determined from the intact cores. Protocol P31 test was performed. Other tests were or will be performed on intact cores using Protocol P32 (compressive strength for other than asphalt treated materials, ATB).

P31, P32

94

The test was not performed because of the oversize aggregate; sample was stored until further instruction from the FHWA-LTPP division.

P46

95

Length to diameter ratio was less than 1.0 because the layer thickness was less than the diameter of the specimen. A correction factor of 0.87 was applied to calculate the compressive strength.

P32

99

Other comment (see the following note).

All

On the test data form, the LTPP standard comment code(s) may have been followed by an explanatory note of up to 25 characters in length.

The following tables provide additional codes used in the description of the materials both in the field and in the laboratory.

4.3.1 LTPP Terminology for Describing Pavements, Pavement Materials and Soils in the Field (field use)

Table 4.25 provides codes used for describing pavement materials in the field. This table was provided within this document to allow laboratory personnel to easily identify the definitions of these codes. This table was reproduced from Appendix C, Table C.2 of the LTPP Field Material Sampling Guide and contains unique three-digit material codes.

Field Use

Table 4.25 was prepared to record material descriptions and codes in the field. The drilling and sampling personnel were required to use these codes to complete borehole, shoulder auger probe and test pit exploration logs.

Table 4.25 contains generic terminology based on the material classifications and codes given in Tables 4.26, 4.29 and 4.32 of this section. For use in the field, Table 4.25 was condensed from the detailed LTPP terminology for pavements, pavement materials and soils described in Tables 4.26, 4.29 and 4.32. Table 4.25 contains: (a) codes for pavement surface material types, (b) codes for unbound granular base and subbase material types, (c) codes for bound base and subbase material types, and (d) codes for subgrade soil types.

General categories for subgrade soils and selected soil types in some of these categories were provided in (d). For example, the code used for the general category of treated soil (treated or stabilized subgrade) was 180. If the field technician/driller was reasonably sure that he had encountered bituminous treated soil then he would use code 183 instead of 180. Similarly the overall code used for clay was 101. In addition, five more detailed codes were included in this category. The driller recorded code 101 on the borehole log for a clay soil. However, if the crew was reasonably certain that the soil could be classified in more detail, such as silty clay (code 131), or sandy clay (code 113), then these codes were used in place of code 101.

Laboratory Use

Table 4.25 was consulted by the materials testing laboratories only for information. Detailed material classification descriptions and codes for pavement materials and soils were to be furnished by the materials testing laboratories using Tables 4.26 to 4.29 in conjunction with appropriate laboratory tests and detailed observations.

Table 4.25. LTPP Terminology for Describing Pavements, Pavement Materials and Soils in the Field.
DESCRIPTION CODE
      (a) Pavement Surface Material Type
Asphaltic Concrete (AC) 700*
Portland Cement Concrete (PCC) 730+
      (b) Unbound Base/Subbase Material Type
Gravel (Uncrushed) 302
Crushed Stone 303
Crushed Gravel 304
Soil-Aggregate Mixture (Predominantly Fine-Grained) 307
Soil-Aggregate Mixture (Predominantly Coarse-Grained) 308
Other (specify if possible or use the term unknown) 310
      (c) Bound Base/Subbase Material Type
Asphalt Treated Mixture 321
Cement Aggregate Mixture 331
Econocrete 332
Lean Concrete 334
Sand-shell Mixture 336
Lime Treated Soil 338
Soil Cement 339
Other (specify if possible or use the term unknown) 350
      (d) Subgrade Soil Type
Clay (C) 101
Clay with Gravel 104
Clay with Sand 107
Gravelly Clay 110
Sandy Clay 113
Silty Clay (CL-ML) 131
Silt (ML) 141
Silt with Gravel 142
Silt with Sand 143
Gravelly Silt 144
Sandy Silt 145
Clayey Silt 148
Peat 151
Treated Soil 180
Lime-Treated Soil 181
Cement-Treated Soil 182
Bituminous-Treated Soil 183
Sand (S) 201
Poorly Graded Sand (SP) 202
Silty Sand (SM) 214
Clayey Sand (SC) 216
Gravel (G) 251
Poorly Graded Gravel (GP) 252
Silty Gravel (GM) 264
Clayey Gravel (GC) 266
Shale 281
Rock 282
Cobbles 283
Boulder 284

Notes: See Tables 4.26, 4.29, 4.32, and 4.35 for detailed description of LTPP terminology and codes.

(a) See Table 4.32 for details of pavement surface type terminology.

*Code 700 was to be used for all AC layers (sand asphalt and other types of surface, wearing, binder or bituminous base course) in the field.

+Code 730 was to be used for all PCC surface types in the field.

(b) and (c) See Table 4.29 for detailed description of base and subbase material terminology.

(d) See Table 4.26 for details of subgrade soil terminology.

4.3.2 Detailed Classification and Description of Soils (laboratory use)

Table 4.26 contains a detailed classification and description of soils based on ASTM D2487-85. Materials codes are also provided in the table for the Unified Soil Classification System.

Laboratory Use

The materials testing laboratories were required to use Table 4.26 for classification and description of subgrade soils (LTPP Protocol P52). Unique three-digit material codes were provided in this table.

The materials testing laboratories used Table 4.26 in conjunction with; (a) the laboratory gradation test results (LTPP Protocol P51 for the subgrade soils), and (b) the laboratory test results of Atterberg Limits (LTPP Protocol P43 for subgrade soils).

The materials testing laboratories also used the Table 4.26 codes for recording subgrade material type on Form L05 (Summary of Pavement Layers) of the LTPP Laboratory Material Testing Guide.

Field Use

Table 4.26 was not used by the drilling and sampling personnel.

Table 4.26. Detailed Classification and Description of Soils.
DESCRIPTION CODE
I. Fine-Grained Soils: Fine-grained soils are those having 50 percent or more by dry weight passing the No. 200 (0.075-mm) sieve. 100
(1) Clay (C): (ASTM D2488-84) Soil passing a No. 200 (0.075-mm) sieve that can be made to exhibit plasticity (putty-like properties) within a range of water contents, and that exhibits considerable strength when air-dry. For classification, clay is a fine-grained soil, or the fine-grained portion of a soil, with a PI equal to or greater than 4, and the plot of PI versus LL falls on or above the "A" line of Figure 3 of ASTM D2487. 101
(2) Inorganic clay (in which the organic matter does not influence the LL) is classified as:
Lean Clay (CL), if the LL is less than 50 102
Fat Clay (CH), if the LL is 50 or greater 103
(3) Further classification of predominantly clay soils is done if less than 30% but 15% or more of the test sample is retained on the No. 200 (0.075-mm) sieve. Add the words "with gravel" or "with sand," whichever is predominant. (ASTM D2488-84)
Clay with Gravel 104
Lean Clay with Gravel 105
Fat Clay with Gravel 106
Clay with Sand 107
Lean Clay with Sand 108
Fat Clay with Sand 109
(Note: Codes 107, 108, and 109 will also apply, if the percent of sand is equal to the percent of gravel.)
(4) For predominantly clay soils the following classification applies, if 30% or more of the test sample is retained on the No. 200 (0.075-mm) sieve. Add the word "gravelly" or "sandy," whichever is predominant to the group symbol. (ASTM D2488-84)
Gravelly Clay 110
Gravelly Lean Clay 111
Gravelly Fat Clay 112
Sandy Clay 113
Sandy Lean Clay 114
Sandy Fat Clay 115
(Note: Codes 113, 114, and 115 will also apply, if the percent of sand is equal to the percent of gravel.
Further division is done by adding the word "with sand" if more than 15% sand is present; or the word "with gravel" if more than 15% gravel is present.
Gravelly Clay with Sand 116
Gravelly Lean Clay with Sand 117
Gravelly Fat Clay with Sand 118
Sandy Clay with Gravel 119
Sandy Lean Clay with Gravel 120
Sandy Fat Clay with Gravel 121
(5) Silty Clay (CL-ML) Combined silt and clay. For material passing 85% or more on the No. 200 (0.075-mm) sieve if the position of the PI versus LL plot falls on or about the A-line and PI is in the range of 4 to 7. (ASTM D2487-85) Silty Clay is further classified according to the percent of sand and/or gravel in the test sample 131
Silty Clay with Gravel (Less than 30% but more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.) 132
Silty Clay with Sand (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.) 133
Gravelly Silty Clay (Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve. 134
Sandy Silty Clay (Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 135
Gravelly Silty Clay with Sand (Equal to or more than 15% sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 136
Sandy Silty Clay with Gravel (More than 15% gravel is present in the predominantly sand fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 137
(6) Silt (ML) Soil passing the No. 200 (0.075-mm) sieve that is non-plastic or very slightly plastic and that exhibits little or no strength when air dry. For classification, silt is a fine-grained soil, or the fine-grained portion of a soil, with LL less than 50 and a PI less than 4, or the plot of PI versus LL falls below the "A" line of Figure 3 of ASTM D2487. (ASTM D2488-84) Silt is further classified according to the percent of sand and/or gravel in the test sample 141
Silt with Gravel (Less than 30% but more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.) 142
Silt with Sand (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.) 143
Gravelly Silt (Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 144
Sandy Silt (Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 145
Gravelly Silt with Sand (15% or more sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 146
Sandy Silt with Gravel (A silt soil containing a predominantly sand fraction at 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve, if which 15% or more is gravel.) 147
Clayey Silt A silt soil containing some clay material with slight plasticity. (ASTM D2488-84) 148
(7) Peat A sample composed primarily of vegetable tissue in various stages of decomposition that has a fibrous to amorphous texture, usually a dark brown to black color, and an organic odor, shall be designated as a highly organic soil and shall be identified as peat. (ASTM D2488-84) 151
(8) Organic Soil (OL/OH) The soil is identified as an organic soil (OL/OH), if the soil contains enough organic particles to influence the soil properties. Organic soils usually have a dark brown to black color and may have an organic odor. Often organic soils will change color, for example, black to brown, when exposed to the air. Some organic soil will lighten in color significantly when air dried. Organic soil normally will not have a high toughness or plasticity. The thread for the toughness test will be spongy. (ASTM D2488-84) For organic soils, the LL after oven drying is less than 75% of the LL of the original specimen determined before oven drying. Organic soil is further classified according to the percent of sand and/or gravel in the test sample. 160
Organic Soil with Gravel (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.) 161
Organic Soil with Sand (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.) 162
Gravelly Organic Soil (Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 163
Sandy Organic Soil (Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 164
Gravelly Organic Soil with Sand (15% or more sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 165
Sandy Organic Soil with Gravel (An organic soil containing predominantly sand fraction at 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve, of which 15% or more is gravel.) 166
(9) In some cases through practice and experience it may be possible to further identify the organic soils as organic silt or organic clay.
      (a) Organic Clay Clay with sufficient organic content to influence the soil properties. For classification, organic clay is a soil that would be classified as clay, except that its LL value after oven drying is less than 75% of its LL value before oven drying. (ASTM D2487-85) Further classification is based on LL and PI. 171
Organic Clay (OL) If the LL (not oven dried) is less than 50%; the PI is 4 or greater and the PI versus LL plot falls on or above the "A" line. 172
Organic Clay (OH) If the LL (not oven dried) is 50% or greater; and the PI versus LL plot falls on or above the "A" line. 173
      (b) Organic Silt Silt with sufficient organic content to influence the soil properties. For classification, organic silt is a soil that would be classified as silt except that its LL value after oven drying is less than 75% of its LL value before oven drying. (ASTM D2487-85) Further classification is based on LL and PI. 176
Organic Silt (OL) If the LL (not oven dried) is less than 50%; the PI is less than 4 or the position of the PI versus LL plot falls below the "A" line. 177
Organic Silt (OH) If the LL (not oven dried) is 50% or greater and the position of the PI versus LL plot falls below the "A" line. 178
(10) Treated Soil (Material codes 180 through 183 are also included in Table 4.29 to indicate treated subgrade soil type) 180
      (a) Lime-Treated Soil The addition of lime to the soil which results in decreased soil density, changes in the plasticity properties of the soil and increased soil strength. 181
      (b) Cement-Treated Soil The addition of portland cement to the soil that produces a hardened soil-cement which increases the stability of the soil. 182
      (c) Bituminous-Treated Soil 183
II. Coarse-Grained Soils The coarse-grained soils are those having 50 percent or less passing the No. 200 (0.075-mm) sieve. 200
(1) Sand (S) Granular material resulting from the disintegration, grinding, or crushing of rock which will pass the No. 10 (2.00-mm) sieve and be retained on the No. 200 (0.075-mm) sieve. Coarse sand is sand passing the No. 10 (2.00-mm) sieve and retained on the No. 40 (0.425-mm) sieve. Fine sand is sand passing the No. 40 (0.425-mm) sieve and retained on the No. 200 (0.075-mm) sieve. (AASHTO M146-70, 1980) 201
Poorly Graded Sand (SP) Predominantly one size or a range of sizes of sand with some intermediate sizes missing and 5% or less fines. 202
Poorly graded sand is further classified according to the plasticity and type of fine fraction and percent of gravel in the test sample.
Poorly Graded Sand with Gravel (With 5% or less fines and 15% or more gravel) 203
Poorly Graded Sand with Silt (SP-SM) (With 10% fines or ML or MH type and less than 15% gravel.) 204
Poorly Graded Sand with Silt and Gravel (With 10% fines of ML or MH type and 15% or more gravel.) 205
Poorly Graded Sand with Clay (SP-SC) (With 10% fines of CL or CH type and less than 15% gravel.) 206
Poorly Graded Sand with Clay and Gravel (With 10% fines of CL or CH type and 15% or more gravel.) 207
Well-Graded Sand (SW) A wide range of particle and substantial amounts of the intermediate particle sizes with 5% or less fines. Well-graded sand is further classified according to the plasticity and type of fine fraction and percent of gravel in the test sample. 208
Well-Graded Sand with Gravel (With 5% or less fines and 15% or more gravel.) 209
Well-Graded Sand with Silt (SW-SM) (With 10% fines of ML or MH type and less than 15% gravel.) 210
Well-Graded Sand with Silt and Gravel (With 10% fines of ML or MH type and 15% or more gravel.) 211
Well-Graded Sand with Clay (SW-SC) (With 10% fines of CL or CH type and less than 15% gravel.) 212
Well-Graded Sand with Clay and Gravel (With 10% fines of CL or CH type and 15% or more gravel.) 213
Silty Sand (SM) Sands with 15% or more fines passing the No. 200 (0.075-mm) sieve having low or no plasticity and less than 15% gravel. The LL and PI based on minus No. 40 (0.425-mm) sieve fraction should plot below the "A" line on the plasticity chart. 214
Silty Sand with Gravel Silty sand with 15% or more fines and 15% or more gravel. 215
Clayey Sand (SC) Sands with less than 15% gravel and 15% or more fines passing the No. 200 (0.075-mm) sieve that are more clay-like and that range in plasticity from low to high. The LLs and PI of soils in this group should plot above the "A" line on the plasticity chart. 216
Clayey Sand with Gravel Clayey sand with 15% or more fines and 15% or more gravel. 217
(2) Gravel (G) Rounded particles of rock which will pass a 3-inch (75-mm) sieve and be retained on a No. 10 (2.00-mm) sieve. Coarse gravel, passing the 3-inch (75-mm) sieve and retained on the 1-inch (25-mm) sieve. Medium gravel, passing the 1-inch (25-mm) sieve and retained on the 1/8-inch (9.5-mm) sieve. Fine gravel, passing the 1/8-inch (9.5-mm) sieve and retained on the No. 10 (2.00-mm) sieve. (AASHTO M146-70, 1980) 251
Poorly Graded Gravel (GP) Poorly graded gravels, gravel-sand mixtures, little or no fines. Predominantly one size or a range of sizes with some intermediate sizes missing. Poorly graded gravel is further classified according to the plasticity and type of fine fraction and percent of sand in the test sample. 252
Poorly Graded Gravel with Sand (With 5% or less fines and 15% or more sand.) 253
Poorly Graded Gravel with Silt (GP-GM) (With 10% fines of ML or MH type and less than 15% sand.) 254
Poorly Graded Gravel with Silt and Sand (With 10% fines of ML or MH type and 15% or more sand.) 255
Poorly Graded Gravel with Clay (GP-GC) (With 10% fines of CL or CH type and less than 15% sand.) 256
Poorly Graded Gravel with Clay and Sand (With 10% fines of CL or CH type and 15% or more sand.) 257
Well-Graded Gravel (GW) It has a wide range of particle sizes and substantial amounts of the intermediate particle sizes. (ASTM D2488-84) Well-graded gravel is further classified according to the plasticity and type of fine fraction and percent of sand in the test sample. 258
Well-Graded Gravel with Sand (With 5% or less fines and 15% or more sand.) 259
Well-Graded Gravel with Silt (GW-GM) (With 10% fines of ML or MH type and less than 15% sand.) 260
Well-Graded Gravel with Silt and Sand (With 10% fines of ML or MH type and 15% or more sand.) 261
Well-Graded Gravel with Clay (GW-GC) (With 10% fines of CL or CH type and less than 15% sand.) 262
Well-Graded Gravel with Clay and Sand (With 10% fines of CL or CH type and 15% or more sand.) 263
Silty Gravel (GM) (With 15% or more fines having low or no plasticity and less than 15% sand.) 264
Silty Gravel with Sand (With 15% or more fines and 15% or more sand.) 265
Clayey Gravel (GC) Gravelly soils with 15% or more fines passing the No. 200 (0.075-mm) sieve that are more clay-like and that range in plasticity from low to high and less than 15% sand. The LLs and PIs of soils in this group should plot above the "A" line on the plasticity chart. 266
Clayey Gravel with Sand (With 15% or more fines and 15% or more sand.) 267
III. Rock and Stone This category includes naturally formed solid mineral matter occurring in large masses, and naturally or crushed angular particles of rock. 280
(1) Shale Gray, black, reddish, or green rock which is fine-grained and composed of, or derived by erosion of sedimentary silts or clays, or of any type of rock that contains clay. The cleavage surfaces of shales are generally dull and earthy. Shale converts to soil after field and/or laboratory processing (crushing, slaking, etc.) 281
(2) Rock Natural solid mineral matter occurring in large masses of fragments. (ASTM D653-85, AASHTO M146-70, 1980). The same code may be used for materials used in rock fill. 282
(3) Cobbles Particles of rock that will pass a 12-inch (305-mm) square opening and be retained on a 3-inch (75-mm) sieve. (ASTM D2488-84) 283
(4) Boulder Particles of rock that will not pass a 12-inch (305-mm) square opening. (ASTM D2488-84) 284
(5) Claystone/Mudstone Claystone and mudstone convert to soil after field and/or laboratory processing (crushing, slaking, etc.) 285
(6) Siltstone Siltstone converts to soil after field and/or laboratory processing (crushing, slaking, etc.) 286
(7) Sandstone Sandstone converts to soil after field and/or laboratory processing (crushing, slaking, etc.) 287
(8) Slag Large fragments of the non-metallic product developed simultaneously with iron in a blast furnace that essentially consists of alumino-silicates of lime and other bases. 288
(9) Shale Chunk Retrieved as 2- to 4-inch (50- to 100-mm) pieces of shale from field. Example of laboratory description: dry, brown, no reaction with hydrochloric acid (HCL). After laboratory processing by slaking in water for 24 hours, material identified as "Sandy Lean Clay (CL)" - 61% of clayey fines, LL = 37, PI = 16, 33% fine to medium sand; 6% gravel-size pieces of shale. 289
(10) Crushed Sandstone Product of commercial crushing operation. Example of laboratory description: "Poorly Graded Sand with Silt (SP-SM)" - 91% fine to medium sand; 9% silty (estimated) fines; dry, reddish-brown, strong reaction with HCL. 290
(11) Crushed Limestone Product of commercial crushing operation on limestone rock pieces. 291
(12) Crushed Rock Processed gravel and cobbles from a pit. Example of laboratory description: "Poorly Graded Gravel (GP)" - 89% fine, hard, angular gravel-size particles; 11% coarse, hard, angular sand-size particles, dry, tan; no reaction with HCL; coefficient of curvature 2.4, and uniformity coefficient 0.9. 292
(13) Broken Shells Example of laboratory description: 62% gravel-size, broken shells; 31% sand and sand-size shell pieces; 7% fines; would be identified as "Poorly Graded Gravel with Sand (GP)." 293
(14) Other (specify if possible or use the term unknown) 294

4.3.2 Detailed Classification and Description of Soils (laboratory use)

Table 4.26 contains a detailed classification and description of soils based on ASTM D2487-85. Materials codes are also provided in the table for the Unified Soil Classification System.

Laboratory Use

The materials testing laboratories were required to use Table 4.26 for classification and description of subgrade soils (LTPP Protocol P52). Unique three-digit material codes were provided in this table.

The materials testing laboratories used Table 4.26 in conjunction with; (a) the laboratory gradation test results (LTPP Protocol P51 for the subgrade soils), and (b) the laboratory test results of Atterberg Limits (LTPP Protocol P43 for subgrade soils).

The materials testing laboratories also used the Table 4.26 codes for recording subgrade material type on Form L05 (Summary of Pavement Layers) of the LTPP Laboratory Material Testing Guide.

Field Use

Table 4.26 was not used by the drilling and sampling personnel.

Table 4.26. Detailed Classification and Description of Soils.
DESCRIPTION CODE
I. Fine-Grained Soils:

Fine-grained soils are those having 50 percent or more by dry weight passing the No. 200 (0.075-mm) sieve.
100
(1) Clay (C): (ASTM D2488-84)

Soil passing a No. 200 (0.075-mm) sieve that can be made to exhibit plasticity (putty-like properties) within a range of water contents, and that exhibits considerable strength when air-dry. For classification, clay is a fine-grained soil, or the fine-grained portion of a soil, with a PI equal to or greater than 4, and the plot of PI versus LL falls on or above the "A" line of Figure 3 of ASTM D2487.
101
(2) Inorganic clay (in which the organic matter does not influence the LL) is classified as:
Lean Clay (CL), if the LL is less than 50 102
Fat Clay (CH), if the LL is 50 or greater 103
(3) Further classification of predominantly clay soils is done if less than 30% but 15% or more of the test sample is retained on the No. 200 (0.075-mm) sieve. Add the words "with gravel" or "with sand," whichever is predominant. (ASTM D2488-84)
Clay with Gravel 104
Lean Clay with Gravel 105
Fat Clay with Gravel 106
Clay with Sand 107
Lean Clay with Sand 108
Fat Clay with Sand 109
(Note: Codes 107, 108, and 109 will also apply, if the percent of sand is equal to the percent of gravel.)
(4) For predominantly clay soils the following classification applies, if 30% or more of the test sample is retained on the No. 200 (0.075-mm) sieve. Add the word "gravelly" or "sandy," whichever is predominant to the group symbol. (ASTM D2488-84)
Gravelly Clay 110
Gravelly Lean Clay 111
Gravelly Fat Clay 112
Sandy Clay 113
Sandy Lean Clay 114
Sandy Fat Clay 115
(Note: Codes 113, 114, and 115 will also apply, if the percent of sand is equal to the percent of gravel.
Further division is done by adding the word "with sand" if more than 15% sand is present; or the word "with gravel" if more than 15% gravel is present.
Gravelly Clay with Sand 116
Gravelly Lean Clay with Sand 117
Gravelly Fat Clay with Sand 118
Sandy Clay with Gravel 119
Sandy Lean Clay with Gravel 120
Sandy Fat Clay with Gravel 121
(5) Silty Clay (CL-ML)

Combined silt and clay. For material passing 85% or more on the No. 200 (0.075-mm) sieve if the position of the PI versus LL plot falls on or about the A-line and PI is in the range of 4 to 7. (ASTM D2487-85)

Silty Clay is further classified according to the percent of sand and/or gravel in the test sample
131
Silty Clay with Gravel

(Less than 30% but more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.)
132
Silty Clay with Sand

(Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.)
133
Gravelly Silty Clay

(Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.
134
Sandy Silty Clay

(Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.)
135
Gravelly Silty Clay with Sand

(Equal to or more than 15% sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.)
136
Sandy Silty Clay with Gravel

(More than 15% gravel is present in the predominantly sand fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.)
137
(6) Silt (ML)

Soil passing the No. 200 (0.075-mm) sieve that is non-plastic or very slightly plastic and that exhibits little or no strength when air dry. For classification, silt is a fine-grained soil, or the fine-grained portion of a soil, with LL less than 50 and a PI less than 4, or the plot of PI versus LL falls below the "A" line of Figure 3 of ASTM D2487. (ASTM D2488-84)

Silt is further classified according to the percent of sand and/or gravel in the test sample
141
Silt with Gravel

(Less than 30% but more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.)
142
Silt with Sand (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.) 143
Gravelly Silt (Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 144
Sandy Silt (Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 145
Gravelly Silt with Sand (15% or more sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 146
Sandy Silt with Gravel (A silt soil containing a predominantly sand fraction at 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve, if which 15% or more is gravel.) 147
Clayey Silt A silt soil containing some clay material with slight plasticity. (ASTM D2488-84) 148
(7) Peat A sample composed primarily of vegetable tissue in various stages of decomposition that has a fibrous to amorphous texture, usually a dark brown to black color, and an organic odor, shall be designated as a highly organic soil and shall be identified as peat. (ASTM D2488-84) 151
(8) Organic Soil (OL/OH) The soil is identified as an organic soil (OL/OH), if the soil contains enough organic particles to influence the soil properties. Organic soils usually have a dark brown to black color and may have an organic odor. Often organic soils will change color, for example, black to brown, when exposed to the air. Some organic soil will lighten in color significantly when air dried. Organic soil normally will not have a high toughness or plasticity. The thread for the toughness test will be spongy. (ASTM D2488-84)

For organic soils, the LL after oven drying is less than 75% of the LL of the original specimen determined before oven drying. Organic soil is further classified according to the percent of sand and/or gravel in the test sample.
160
Organic Soil with Gravel (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly gravel.) 161
Organic Soil with Sand (Less than 30% but equal to or more than 15% retained on the No. 200 [0.075-mm] sieve is predominantly sand.) 162
Gravelly Organic Soil (Gravel is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 163
Sandy Organic Soil (Sand is predominant in the fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 164
Gravelly Organic Soil with Sand (15% or more sand is present in the predominantly gravel fraction of 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve.) 165
Sandy Organic Soil with Gravel (An organic soil containing predominantly sand fraction at 30% or more of the test sample retained on the No. 200 [0.075-mm] sieve, of which 15% or more is gravel.) 166
(9) In some cases through practice and experience it may be possible to further identify the organic soils as organic silt or organic clay.
(a) Organic Clay Clay with sufficient organic content to influence the soil properties. For classification, organic clay is a soil that would be classified as clay, except that its LL value after oven drying is less than 75% of its LL value before oven drying. (ASTM D2487-85) Further classification is based on LL and PI. 171
Organic Clay (OL) If the LL (not oven dried) is less than 50%; the PI is 4 or greater and the PI versus LL plot falls on or above the "A" line. 172
Organic Clay (OH) If the LL (not oven dried) is 50% or greater; and the PI versus LL plot falls on or above the "A" line. 173
(b) Organic Silt Silt with sufficient organic content to influence the soil properties. For classification, organic silt is a soil that would be classified as silt except that its LL value after oven drying is less than 75% of its LL value before oven drying. (ASTM D2487-85) Further classification is based on LL and PI. 176
Organic Silt (OL) If the LL (not oven dried) is less than 50%; the PI is less than 4 or the position of the PI versus LL plot falls below the "A" line. 177
Organic Silt (OH) If the LL (not oven dried) is 50% or greater and the position of the PI versus LL plot falls below the "A" line. 178
(10) Treated Soil (Material codes 180 through 183 are also included in Table 4.29 to indicate treated subgrade soil type) 180
(a) Lime-Treated Soil The addition of lime to the soil which results in decreased soil density, changes in the plasticity properties of the soil and increased soil strength. 181
(b) Cement-Treated Soil The addition of portland cement to the soil that produces a hardened soil-cement which increases the stability of the soil. 182
(c) Bituminous-Treated Soil 183
II. Coarse-Grained Soils The coarse-grained soils are those having 50 percent or less passing the No. 200 (0.075-mm) sieve. 200
(1) Sand (S) Granular material resulting from the disintegration, grinding, or crushing of rock which will pass the No. 10 (2.00-mm) sieve and be retained on the No. 200 (0.075-mm) sieve. Coarse sand is sand passing the No. 10 (2.00-mm) sieve and retained on the No. 40 (0.425-mm) sieve. Fine sand is sand passing the No. 40 (0.425-mm) sieve and retained on the No. 200 (0.075-mm) sieve. (AASHTO M146-70, 1980) 201
Poorly Graded Sand (SP) Predominantly one size or a range of sizes of sand with some intermediate sizes missing and 5% or less fines. 202
Poorly graded sand is further classified according to the plasticity and type of fine fraction and percent of gravel in the test sample.
Poorly Graded Sand with Gravel (With 5% or less fines and 15% or more gravel) 203
Poorly Graded Sand with Silt (SP-SM) (With 10% fines or ML or MH type and less than 15% gravel.) 204
Poorly Graded Sand with Silt and Gravel (With 10% fines of ML or MH type and 15% or more gravel.) 205
Poorly Graded Sand with Clay (SP-SC) (With 10% fines of CL or CH type and less than 15% gravel.) 206
Poorly Graded Sand with Clay and Gravel (With 10% fines of CL or CH type and 15% or more gravel.) 207
Well-Graded Sand (SW) A wide range of particle and substantial amounts of the intermediate particle sizes with 5% or less fines. Well-graded sand is further classified according to the plasticity and type of fine fraction and percent of gravel in the test sample. 208
Well-Graded Sand with Gravel (With 5% or less fines and 15% or more gravel.) 209
Well-Graded Sand with Silt (SW-SM) (With 10% fines of ML or MH type and less than 15% gravel.) 210
Well-Graded Sand with Silt and Gravel (With 10% fines of ML or MH type and 15% or more gravel.) 211
Well-Graded Sand with Clay (SW-SC) (With 10% fines of CL or CH type and less than 15% gravel.) 212
Well-Graded Sand with Clay and Gravel (With 10% fines of CL or CH type and 15% or more gravel.) 213
Silty Sand (SM) Sands with 15% or more fines passing the No. 200 (0.075-mm) sieve having low or no plasticity and less than 15% gravel. The LL and PI based on minus No. 40 (0.425-mm) sieve fraction should plot below the "A" line on the plasticity chart. 214
Silty Sand with Gravel Silty sand with 15% or more fines and 15% or more gravel. 215
Clayey Sand (SC) Sands with less than 15% gravel and 15% or more fines passing the No. 200 (0.075-mm) sieve that are more clay-like and that range in plasticity from low to high. The LLs and PI of soils in this group should plot above the "A" line on the plasticity chart. 216
Clayey Sand with Gravel Clayey sand with 15% or more fines and 15% or more gravel. 217
(2) Gravel (G) Rounded particles of rock which will pass a 3-inch (75-mm) sieve and be retained on a No. 10 (2.00-mm) sieve. Coarse gravel, passing the 3-inch (75-mm) sieve and retained on the 1-inch (25-mm) sieve. Medium gravel, passing the 1-inch (25-mm) sieve and retained on the 1/8-inch (9.5-mm) sieve. Fine gravel, passing the 1/8-inch (9.5-mm) sieve and retained on the No. 10 (2.00-mm) sieve. (AASHTO M146-70, 1980) 251
Poorly Graded Gravel (GP) Poorly graded gravels, gravel-sand mixtures, little or no fines. Predominantly one size or a range of sizes with some intermediate sizes missing. Poorly graded gravel is further classified according to the plasticity and type of fine fraction and percent of sand in the test sample. 252
Poorly Graded Gravel with Sand (With 5% or less fines and 15% or more sand.) 253
Poorly Graded Gravel with Silt (GP-GM) (With 10% fines of ML or MH type and less than 15% sand.) 254
Poorly Graded Gravel with Silt and Sand (With 10% fines of ML or MH type and 15% or more sand.) 255
Poorly Graded Gravel with Clay (GP-GC) (With 10% fines of CL or CH type and less than 15% sand.) 256
Poorly Graded Gravel with Clay and Sand (With 10% fines of CL or CH type and 15% or more sand.) 257
Well-Graded Gravel (GW) It has a wide range of particle sizes and substantial amounts of the intermediate particle sizes. (ASTM D2488-84) Well-graded gravel is further classified according to the plasticity and type of fine fraction and percent of sand in the test sample. 258
Well-Graded Gravel with Sand (With 5% or less fines and 15% or more sand.) 259
Well-Graded Gravel with Silt (GW-GM) (With 10% fines of ML or MH type and less than 15% sand.) 260
Well-Graded Gravel with Silt and Sand (With 10% fines of ML or MH type and 15% or more sand.) 261
Well-Graded Gravel with Clay (GW-GC) (With 10% fines of CL or CH type and less than 15% sand.) 262
Well-Graded Gravel with Clay and Sand (With 10% fines of CL or CH type and 15% or more sand.) 263
Silty Gravel (GM) (With 15% or more fines having low or no plasticity and less than 15% sand.) 264
Silty Gravel with Sand (With 15% or more fines and 15% or more sand.) 265
Clayey Gravel (GC) Gravelly soils with 15% or more fines passing the No. 200 (0.075-mm) sieve that are more clay-like and that range in plasticity from low to high and less than 15% sand. The LLs and PIs of soils in this group should plot above the "A" line on the plasticity chart. 266
Clayey Gravel with Sand (With 15% or more fines and 15% or more sand.) 267
III. Rock and Stone This category includes naturally formed solid mineral matter occurring in large masses, and naturally or crushed angular particles of rock. 280
(1) Shale Gray, black, reddish, or green rock which is fine-grained and composed of, or derived by erosion of sedimentary silts or clays, or of any type of rock that contains clay. The cleavage surfaces of shales are generally dull and earthy.

Shale converts to soil after field and/or laboratory processing (crushing, slaking, etc.)
281
(2) Rock

Natural solid mineral matter occurring in large masses of fragments. (ASTM D653-85, AASHTO M146-70, 1980). The same code may be used for materials used in rock fill.
282
(3) Cobbles

Particles of rock that will pass a 12-inch (305-mm) square opening and be retained on a 3-inch (75-mm) sieve. (ASTM D2488-84)
283
(4) Boulder

Particles of rock that will not pass a 12-inch (305-mm) square opening. (ASTM D2488-84)
284
(5) Claystone/Mudstone
Claystone and mudstone convert to soil after field and/or laboratory processing (crushing, slaking, etc.)
285
(6) Siltstone

Siltstone converts to soil after field and/or laboratory processing (crushing, slaking, etc.)
286
(7) Sandstone

Sandstone converts to soil after field and/or laboratory processing (crushing, slaking, etc.)
287
(8) Slag

Large fragments of the non-metallic product developed simultaneously with iron in a blast furnace that essentially consists of alumino-silicates of lime and other bases.
288
(9) Shale Chunk

Retrieved as 2- to 4-inch (50- to 100-mm) pieces of shale from field. Example of laboratory description: dry, brown, no reaction with hydrochloric acid (HCL). After laboratory processing by slaking in water for 24 hours, material identified as "Sandy Lean Clay (CL)" - 61% of clayey fines, LL = 37, PI = 16, 33% fine to medium sand; 6% gravel-size pieces of shale.
289
(10) Crushed Sandstone

Product of commercial crushing operation. Example of laboratory description: "Poorly Graded Sand with Silt (SP-SM)" - 91% fine to medium sand; 9% silty (estimated) fines; dry, reddish-brown, strong reaction with HCL.
290
(11) Crushed Limestone

Product of commercial crushing operation on limestone rock pieces.
291
(12) Crushed Rock

Processed gravel and cobbles from a pit. Example of laboratory description: "Poorly Graded Gravel (GP)" - 89% fine, hard, angular gravel-size particles; 11% coarse, hard, angular sand-size particles, dry, tan; no reaction with HCL; coefficient of curvature 2.4, and uniformity coefficient 0.9.
292
(13) Broken Shells

Example of laboratory description: 62% gravel-size, broken shells; 31% sand and sand-size shell pieces; 7% fines; would be identified as "Poorly Graded Gravel with Sand (GP)."
293
(14) Other (specify if possible or use the term unknown) 294

4.3.3 Soil Descriptions and Material Codes Based on Visual Methods (laboratory use)

The classification and description of soils based on the visual-manual methods of ASTM D2488-84 and associated material codes were included in Table 4.27. The tables, numbered (1) to (14) included in Table 4.27 were taken from ASTM D2488-84.

Laboratory Use

The materials testing laboratories were required to use Table 4.27 for classification and description of unbound granular base and subbase materials (LTPP Protocol P47) and subgrade soils (LTPP Protocol P52). Table 4.27 was also used for description of treated base and subbase materials and treated subgrade. Unique four-digit material codes were defined in this table.

The materials testing laboratories used Table 4.27 in conjunction with: (a) the visual-manual procedures described in ASTM D2488-84, (b) the laboratory test results obtained from the gradation and Atterberg Limits tests as appropriate (LTPP Protocols P41, P43, P51).

Field Use

Table 4.27 was not used by the drilling and sampling personnel.

Table 4.27. Soils Descriptions and Material Codes Based on Visual Methods.
DESCRIPTION CRITERIA CODE
(1) Criteria for Describing Angularity of Coarse-Grained Particles (See Figure 3 of ASTM D2488-84)
Angular Particles have sharp edges and relatively plane sides with unpolished surfaces 2101
Subangular Particles are similar to angular description but have rounded edges 2102
DESCRIPTION CRITERIA CODE
Subrounded Particles have nearly plane sides but have well-rounded corners and edges 2103
Rounded Particles have smoothly curved sides and no edges 2104
(2) Criteria for Describing Particle Shape (See Figure 4 of ASTM D2488-84) The particle shape shall be described as follows where length, width, and thickness refer to the greatest, intermediate, and least dimensions of a particle, respectively.
Flat Particles with width/thickness > 3 2201
Elongated Particles with length/width > 3 2202
Flat and elongated Particles meet criteria for both flat and elongated 2203
(3) Criteria for Describing Moisture Condition
Dry Absence of moisture, dusty, dry to the touch 1301
Moist Damp but no visible water 1302
Wet Visible free water, usually soil is below water table 1303
(4) Criteria for Describing the Reaction with HCL
None No visible reaction 2301
Weak Some reaction, with bubbles forming slowly 2302
Strong Violent reaction, with bubbles forming immediately 2303
(5) Criteria for Describing Consistency
Very soft Thumb will penetrate soil more than 1 in. (25 mm) 1401
Soft Thumb will penetrate soil about 1 in. (25 mm) 1402
Firm Thumb will indent soil about ¼ in. (6 mm) 1403
Hard Thumb will not indent soil but readily indented with thumbnail 1404
Very hard Thumbnail will not indent soil 1405
(6) Criteria for Describing Cementation
Weak Crumbles or breaks with handling or little finger pressure 1501
Moderate Crumbles or breaks with considerable finger pressure 1502
Strong Will not crumble or break with finger pressure 1503
(7) Criteria for Describing Structure
Stratified Alternating layers of varying material or color with layers at least ¼-inch (6-mm) thick; note thickness 1601
Laminated Alternating layers of varying material or color with the layers less than ¼-inch (6-mm) thick; note thickness 1602
Fissured Breaks along definite planes of fracture with little resistance to fracturing 1603
Slickensided Fracture planes appear polished or glossy sometimes striated 1604
Blocky Cohesive soil that can be broken down into small angular lumps which resist further breakdown 1605
Lensed Inclusion of small pockets of different soils, such as small lenses of sand scattered through a mass of clay; note thickness 1606
Homogenous Same color and appearance throughout 1607
(8) Criteria for Describing Dry Strength
None The dry specimen crumbles into powder with mere pressure of handling 1701
DESCRIPTION CRITERIA CODE
Low The dry specimen crumbles into powder with some finger pressure 1702
Medium The dry specimen breaks into pieces or crumbles with considerable finger pressure 1703
High The dry specimen cannot be broken with finger pressure. Specimen will break into pieces between thumb and a hard surface 1704
Very high The dry specimen cannot be broken between the thumb and a hard surface 1705
(9) Criteria for Describing Dilatancy
None No visible change in the specimen 1801
Slow Water appears slowly on the surface of the specimen during shaking and does not disappear or disappears slowly upon squeezing 1802
Rapid Water appears quickly on the surface of the specimen during shaking and disappears quickly upon squeezing 1803
(10) Criteria for Describing Toughness
Low Only slight pressure is required to roll the thread near the PL. The thread and the lump are weak and soft 1901
Medium Medium pressure is required to roll the thread to near the PL. The thread and the lump have medium stiffness 1902
High Considerable pressure is required to roll the thread to near the PL. The thread and the lump have very high stiffness. 1903
(11) Criteria for Describing Plasticity
Nonplastic A 1/8-inch (3-mm) thread cannot be rolled at any water content 1201
Low The thread can barely be rolled and the lump cannot be formed when drier than the PL 1202
Medium The thread is easy to roll and not much time is required to reach the PL. The thread cannot be rerolled after reaching PL. The lump crumbles when drier than the PL. 1203
High It takes considerable time rolling and kneading to reach the PL. The thread can be rerolled several times after reaching the PL. The lump can be formed without crumbling when drier than the PL. 1204
(12) Criteria for Describing Color
Colors of soils should be reported on field exploration logs and laboratory test reports with other material description information as appropriate. There is no material code for this purpose.
(13) Identification of Inorganic Fine-Grained Soils from Manual Tests
SOIL SYMBOL DRY STRENGTH DILATANCY TOUGHNESS CODE
ML None to low Slow to rapid Low or thread cannot be formed 1101
CL Medium to high None to slow Medium 1102
MH Low to medium None to slow Low to medium 1103
CH High to very high None High 1104
(14) Criteria for Relative Density of Coarse-grained Soils
PENETRATION RESISTANCE*, Blows/Foot DESCRIPTIVE TERM RELATIVE DENSITY CODE
0 to 4 Very Loose 0 to 20% 2001
4 to 10 Loose 20% to 40% 2002
10 to 30 Medium Dense 40% to 70% 2003
30 to 50 Dense 70% to 90% 2004
Over 50 Very Dense 90% to 100% 2005
Includes (1) clean, fine gravels and sands, depending on distribution of grain sizes and (2) silty or clayey fine gravels and sands. Condition was rated according to relative density, as determined by laboratory tests or estimated from resistance to sampler penetration.
*Penetration resistance was recorded on borehole logs at locations A1 and A2 on the pavement section by the Drilling and Sampling Contractor.

4.3.4 AASHTO Classification for Soil and Soil-Aggregate Materials (laboratory use)

Material codes for the AASHTO classification of soils and soil-aggregate materials based on AASHTO M145-87I were included in Table 4.28.

Laboratory Use

The materials testing laboratories used Table 4.28 for classification and description of subgrade soils (LTPP Protocol P52). Unique three-digit material codes were defined in this table.

The materials testing laboratories used Table 4.28 in conjunction with; (a) the procedures described in AASHTO M145-87I, (b) the laboratory gradation test results (LTPP Protocol P51 for the subgrade soils), and (c) the laboratory test results of Atterberg Limits (LTPP Protocol P43 for subgrade soils). The materials testing laboratories report a specific classification in the A-1 group; for example, a soil should be classified either A-1-a (material code 502) or A-1-b (material code 503).

Field Use

Table 4.28 was not used by the drilling and sampling personnel.

Table 4.28. AASHTO Classification for Soil and Soil-Aggregate Material Types.
MATERIAL TYPE DESCRIPTION CODE
A-1 The typical material of this group is a well-graded mixture of stone fragments or gravel, coarse sand, fine sand, and a non-plastic or feebly plastic soil binder. However, this group includes also stone fragments, gravel, coarse sand, volcanic cinders, etc. without soil binder. (AASHTO M145-82) 501
A-1-a Subgroup A-1-a includes those materials consisting predominantly of stone fragments or gravel, either with or without a well-graded binder of fine material. (AASHTO M145-82) 502
A-1-b Subgroup A-1-b includes those materials consisting predominantly of coarse sand either with or without a well-graded soil binder. (AASHTO M145-82) 503
A-2 This group includes a wide variety of "granular" materials which are border-line between the materials falling in Groups A-1 and A-3 and silt-clay materials of Group A-4, A-5, A-6, and A-7. It includes all materials containing 35 percent or less passing the No. 200 (0.075-mm) sieve which cannot be classified as A-1 or A-3, due to fines content or plasticity or both, in excess of the limitations for those groups. (AASHTO M145-82) 505
A-2-4 A-2-5 Subgroups A-2-4 and A-2-5 include various granular materials containing 35 percent or less passing the No. 200 (0.075-mm) sieve and with a minus No. 40 (0.425-mm) portion having the characteristics of the A-4 and A-5 groups. These groups include such materials as gravel and coarse sand with silt contents or PIs in excess of the limitations of Group A-1, and fine sand with non-plastic silt content in excess of the limitations of Group A-3. (AASHTO M145-82) 506 507
A-2-6 A-2-7 Subgroups A-2-6 and A-2-7 include materials similar to those described under Subgroups A-2-4 and A-2-5 except that the fine portion contains plastic clay having the characteristics of the A-6 or A-7 group. (AASHTO M145-82) 508 509
A-3 The typical material of this group is fine beach sand or fine desert blow sand without silty or clay fines or with a very small amount of non-plastic silt. The group includes also stream-deposited mixtures of poorly-graded fine sand and limited amounts of coarse sand and gravel. (AASHTO M145-82) 504
A-4 The typical material of this group is a non-plastic or moderately plastic silty soil having 75 percent or more passing the No. 200 (0.075-mm) sieve. The group includes also mixtures of fine silty soil and up to 64 percent of sand and gravel retained on the No. 200 (0.075-mm) sieve. (AASHTO M145-82) 510
A-5 The typical material of this group is similar to that described under Group A-4, except that it is usually of diatomaceous or micaceous character and may be highly elastic as indicated by the high LL. (AASHTO M145-82) 511
A-6 The typical material of this group is a plastic clay soil usually having 75 percent or more passing the No. 200 (0.075-mm) sieve. The group includes also mixtures of fine clayey soil and up to 64 percent of sand and gravel retained on the No. 200 (0.075-mm) sieve. Materials of this group usually have high volume change between wet and dry states. (AASHTO M145-82) 512
A-7 The typical material of this group is similar to that described under Group A-6, except that it has the high LLs characteristic of the A-5 group and may be elastic as well as subject to high volume change. (AASHTO M145-82) 513
A-7-5 Subgroup A-7-5 includes those materials with moderate PIs in relation to LL and which may be highly elastic as well as subject to considerable volume change. (AASHTO M145-82) 514
A-7-6 Subgroup A-7-6 includes those materials with high PIs in relation to LL and which are subject to extremely high volume change. (AASHTO M145-82) 515

Notes: 1. Follow AASHTO M145-82 (1986) procedures to classify the material according to these AASHTO classification groups and then assign appropriate material codes. Use specific classification in A-1 group; for example a soil should be classified either A-1-a (material code 502) or A-1-b (material code 503)
2. According to Tables 1 and 2 of AASHTO M145-82 (1986):

Granular Material Groups (35% or less Passing No. 200 [0.075-mm]) Silt-Clay Material Groups (More than 35% Passing No. 200 [0.075-mm] Sieve)
A-1 (Stone fragments, gravel and sand)
A-3 (Non-plastic fine sand)
A-2 (Silty or clayey gravel and sand)
A-4 (Silty soils)
A-5 (Silty soils)
A-6 (Clayey soils)
A-7 (Clayey soils)

4.3.5 Base and Subbase Materials Description (laboratory use)

Table 4.29 contains description and material codes of all types of base and subbase materials based on material processing and construction methods.

Laboratory Use

The materials testing laboratories used Table 4.29 for description of all types of treated base and subbase materials (LTPP Protocol P31) and all types of untreated unbound granular base and subbase materials (LTPP Protocol P47). Unique three-digit material codes were defined in this table.

The materials testing laboratories used Table 4.29 in conjunction with; (a) detailed descriptions made during bulk sample handling, (b) test preparation for gradation and other laboratory tests, (c) the laboratory gradation test results (LTPP Protocol P41 for the unbound granular base and subbase material) and (d) description and type of treatment for treated base and subbase materials and treated subgrade (LTPP Protocol P31).

The materials testing laboratories used Table 4.29 codes for recording base and subbase layer material information on Form L05 (Summary of Pavement Layers).

Field Use

Some major categories of description and associated material codes of all types of base and subbase materials from Table 4.29 were also used in Table 4.25 (included in this Chapter). Table 4.25 was used by the drilling and sampling personnel to complete the borehole, shoulder auger probe and test pit exploration logs.

Table 4.29. Base and Subbase Materials Description.
MATERIAL TYPE DESCRIPTION CODE
1. Detailed Description of Unbound Granular Base/Subbase Material Unbound Granular Base: Unbound granular base layer material includes material codes 302 through 308, 310. Unbound Granular Subbase: Unbound granular subbase layer material includes material codes 302 through 308, 310.
Gravel (Uncrushed) The product resulting from screening blending of material from the deposit, consisting of particles with a shape and texture largely dependent on the nature of the deposit. The product may include some particles with fracture faces resulting from crushing oversize material. (ASTM D1139-83) 302
Crushed Stone The product resulting from the artificial crushing of rocks, boulders, or large cobblestones, substantially all faces of which have resulted from the crushing operation. (ASTM D1139-83) 303
Crushed Gravel The product resulting from the crushing of gravel, with a requirement that at least a prescribed percentage of the resulting particles have fracture faces. Some uncrushed particles may be included. (ASTM D1139-82) 304
Crushed Slag The nonmetallic product, consisting essentially of silicates and alumino-silicates of lime and of other bases, that is developed simultaneously with iron in a blast furnace. The product resulting from the crushing of air-cooled iron blast-furnace slag. (ASTM D1139-83) 305
Sand Fine aggregate resulting from natural disintegration and abrasion of rock or processing of completely friable sandstone. 306
Soil-Aggregate Mixture (Predominantly Fine-Grained Soil) Natural or prepared mixture of fine-grained soil with a percentage of aggregates included in the mixture. This material meets the criteria of less than 70 percent passing the No. 10 (2.00-mm) sieve and more than 35 percent passing the No. 200 (0.075-mm) sieve. Typically this material includes all those materials which do not meet the criteria given below for the predominantly coarse-grained soil aggregate mixture. Note: If greater than 70 percent passes the No. 10 (2.00-mm) sieve, then the material is considered a soil. If less than 70 percent passes the No. 10 (2.00-mm) sieve, the material should be considered a soil-aggregate mixture. 307
Soil-Aggregate Mixture (Predominantly Coarse-Grained Soil) Natural or prepared mixtures of coarse-grained soil with a percentage of aggregates included in the mixture. Typically this material meets the criteria of less than 70 percent passing the No. 10 (2.00-mm) sieve and less than 35 percent passing the No. 200 (0.075-mm) sieve. 308
Fine-Grained Soil This material meets the criteria of more than 70 percent passing the No. 10 (2.00-mm) sieve and more than 50 percent passing the No. 200 (0.075-mm) sieve. 309
Other (Specify if possible or use the term unknown) 310
2. Detailed Description of Treated Base/Subbase Material
Treated Base/Subbase Treated base/subbase material includes material codes 319 through 341, 350. The asphalt treated material (ATB) consists of material codes 319 through 330. Other than asphalt treated material (OTB) consists of material codes 331 through 341.
HMAC HMAC (hot-mix, hot-laid asphaltic concrete) is a mixture of heated coarse and fine aggregate or fine aggregate alone, with or without mineral filler, uniformly mixed with asphalt cement. Typically HMAC material is produced in an asphalt plant or drum mixer and laid hot at the paving site for AC surface, wearing, binder, and bituminous base courses. 319
Sand Asphalt A mixture of sand and asphalt cement or cutback or emulsified asphalt. It may be prepared with or without special control of aggregate grading and may or may not contain mineral filler. Either mixed-in-place or plant-mix construction may be employed. Sand-asphalt is used in construction of both base and surface courses. 320
Asphalt-Treated Mixture (Also called Asphalt-Treated Base, ATB, Black Base) General term used for all types of bituminous treated material. With the exception of HMAC material (material codes 700, 319) and Sand Asphalt (material codes 02, 320). 321
Dense Graded Hot Laid Central Plant Mix A mixture of asphalt cement and mineral aggregate prepared in a central bituminous mixing plant and spread and compacted at the job site at a temperature above ambient temperature, and containing an aggregate that has a particle size distribution such that when it is compacted, the resulting voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, are relatively small. 322
Dense-Graded, Cold-Laid, Central Plant Mix A mixture of cut-back asphalt, bituminous emulsion or tar and mineral aggregate prepared in a central bituminous mixing plant and spread and compacted at the job site when the mixture is at or near ambient temperature containing an aggregate that has a particle size distribution such that when it is compacted, the resulting voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, are relatively small. 323
Dense-Graded, Cold-Laid, Mixed In-Place A bituminous surface or base course produced by mixing mineral aggregate and cut-back asphalt, bituminous emulsion, or tar at the job-site by means of travel plants, motor graders, drags, or special road-mixing equipment designed to be laid either shortly after mixing or when the mixture is at or near ambient temperature, and containing an aggregate that has a particle size distribution such that when it is compacted, the resulting voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, are relatively small. 324
Open-Graded, Hot-Laid, Central Plant Mix A mixture of emulsion and heated mineral aggregate usually prepared in a conventional asphalt plant or drum mixer and spread and compacted at the job site at a temperature above ambient containing an aggregate that has a particle size distribution such that when it is compacted, the voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, remain relatively large. 325
Open-Graded, Cold-Laid, Central Plant Mix A mixture of cut-back asphalt, bituminous emulsion, or tar and mineral aggregate prepared in a central bituminous mixing plant and spread and compacted at the job-site when the mixture is at or near ambient temperature containing an aggregate that has a particle size distribution such that when it is compacted, the voids between the aggregate particles, expressed as a percentage of the total space occupied by the material, remain relatively large. 326
Open-Graded, Cold-Laid, Mixed-in-Place A bituminous base or subbase course produced by mixing mineral aggregate and cut-back asphalt, bituminous emulsion, or tar at the job-site by means of travel plants, motor graders, drags, or special road-mixing equipment designed to be laid either shortly after missing or when the mixture is at or near ambient temperature, and containing an aggregate that has a particle size distribution such that when it is compacted, the voids between the aggregate particles, expressed as a percentage of total space occupied by the material, remain relatively large. 327
Recycled Asphalt Concrete, Plant Mix, Hot Laid HMAC containing reclaimed AC which is mixed at the plant, transported to the job site and laid at a temperature substantially higher than ambient temperature. 328
Recycled Asphalt Concrete, Plant Mix, Cold Laid A cold laid bituminous mixture containing reclaimed asphalt concrete which is batch mixed at the plant, transported to the job site and laid at ambient temperature. 329
Recycled Asphalt Concrete, Mixed-In-Place A bituminous concrete layer containing reclaimed asphalt concrete which is mixed in-place and laid at the job site at ambient temperature. 330
Cement Aggregate Mixture (Also called cement-treated base, CTB) A mixture of aggregate and soil binder treated with portland cement and used as base or subbase to increase the stability of the pavement structure. Typically 4 to 8 percent portland cement is used to achieve a specified minimum value of compressive strength. The materials may have been mixed in-place or produced at a batch or a continuous mixing plant. 331
Lean Concrete (Also called lean-concrete base, LCB) A PCC mixture with a relatively low cement content. 334
Econocrete A PCC mixture made with marginal aggregate and a relatively low cement content. 332
Cement-Treated Soil The addition of cement to the soil to improve the plasticity characteristics of the soil and its load bearing capacity. 333
Recycled Portland Cement Concrete Waste concrete which has been crushed which will have at least three-quarters of the compressive strength, good workability and durability and two-thirds of the modulus of elasticity of regular, new concrete. Recycled PCC mixture is produced using crushed and processed PCC for more than 50 percent of the total aggregate. 335
Sand-Shell Mixture A mixture of sandy material and shell fragment or material used in the subbase or base course or a mixture of processed shell blended with predominantly coarse-grained soil. 336
Limerock, Caliche Soft Carbonate Rock. Caliche is a granular material consisting of at least 70 percent calcium carbonate, obtained from the processing of a soft carbonate rock (lime rock) or calcium carbonate deposits precipitated underground in arid environments. The granular material will pass a 3-inch (76-mm) sieve and will typically contain a relatively high percentage passing the No. 40 (0.425-mm) sieve. 337
Lime-Treated Soil The addition of lime to soil (usually fine-grained) which results in decreased soil density, changes in the plasticity properties of the soil and increased soil strength (also called lump-modified soil). 338
Soil Cement Soil (generally granular soil) bound by portland cement to produce a hardened soil-cement mixture with a requirement for minimum compressive strength. Soil cement generally has a higher cement content than that used in cement-treated soil. 339
Pozzolanic- Aggregate Mixture A mixture of natural pozzolanic aggregate or soil or flyash material that produces a stiff bound material with cementitious properties. 340
Cracked and Seated PCC Layer The original cracked PCC surface layer has been broken or cracked and seated by rolling this material. May not be salvageable from core sampling. 341
Other (Specify if possible or use the term unknown) 350
3. Detailed Description of Treated Subgrade Soil
Treated Subgrade Soil For the LTPP-GPS study, a treated subgrade soil is considered a treated subbase layer. Material code 180 indicates a general term for treated subgrade soils. Material codes 180 through 183 are also included in Table 4.26 of this Guide. 180
Lime-Treated Soil The addition of lime to the soil which results in decreased soil density, changes in plasticity properties of the soil and increased soil strength. 181
Cement-Treated Subgrade Soil The addition of cement to the soil to improved the plasticity properties of the soil and its load carrying capacity. 182
Bituminous Treated Subgrade Soil The soil treated with bituminous materials to improve the soil strength. 183
4. Type of Treatment in Treated Base/Subbase/Subgrade Material
Lime - includes all classes of quick lime and hydrated lime 351
Lime-flyash 352
Lime- and cement-flyash 353
Cement - portland cement 354
Bitumen - includes all classes of bituminous and asphalt treatments 355
Calcium Chloride 356
Sodium Chloride 357
Other Chemical Treatment - includes polymer stabilization 358
Other (specify if possible or use the term unknown) 360

4.3.6 Aggregate Type Description (laboratory use)

Description and material codes for coarse and fine aggregate types were listed in Table 4.30.

Laboratory Use

The materials testing laboratories used Table 4.30 for describing the coarse aggregate type for treated base and subbase materials (LTPP Protocol P31). The aggregate type description was reported with the results of LTPP Protocol P31 by the materials testing laboratories. Unique three-digit codes were defined in this table.

Field Use

Table 4.30 was not used by the drilling and sampling personnel.

Table 4.30. Aggregate Type Description
TYPE AND DESCRIPTION CODE
1. Coarse Aggregate: Aggregate predominantly retained on the No. 4 (4.75-mm) sieve; or that portion of an aggregate retained on the No. 4 (4.75-mm) sieve. (ASTM C125-85)
Gravel: (See Table 4.29 for definition, same as Code 302) 401
Crushed Stone: (See Table 4.29 for definition, same as Code 303) 402
Crushed Gravel: (See Table 4.29 for definition, same as Code 304) 403
Crushed Slag; (See Table 4.29 for definition, same as Code 305) 404
Blend: The combination of several sizes of coarse aggregate to form a uniformly graded composition of materials. 405
Manufactured: Coarse aggregate produced by crushing rock, gravel iron blast furnace slag, or hydraulic-cement concrete. 406
Light Weight: Aggregate of low density used to produce lightweight concrete, included; pumice, scoria, volcanic cinders, tuff and diatomite; expanded or sintered clay, shale, slate, diatomaceous shale, perlite, vermiculate, or slag; and end products of coal or coke combustion. (ASTM C125-85) 407
Other: (Specify if possible or use the term unknown) 408
2. Fine Aggregate: Aggregate passing the 1/8-inch (9.5-mm) sieve and almost entirely passing the No. 4 (4.75-mm) sieve and predominantly retained on the No. 200 (0.075-mm) sieve; or that portion of an aggregate passing the No. 4 (4.75-mm) sieve and retained on the No. 200 (0.075-mm) sieve. (ASTM C125-85)
Natural Sand: (See Table 4.26, Code 201 for definition) 409
Manufactured Sand: Fine aggregate produced by crushing rock, gravel, iron blast furnace slag, or hydraulic-cement concrete. (ASTM C125-85) 410
Blend: The combination of several differently sized fine aggregates to produce a uniformly graded mixture of materials. 411
Other: (Specify if possible or use the term unknown) 412

4.3.7 Geologic Classification Codes (laboratory use)

Geologic classification codes for coarse aggregates are listed in Table 4.31.

Laboratory Use

The materials testing laboratories used Table 4.31 for recording the geologic description of aggregate for: (a) treated base and subbase materials using LTPP Protocol P31 and (b) extracted aggregate from AC using LTPP Protocol P14. Unique two-digit codes were defined in this table.

Field Use

Table 4.31 was not used by the drilling and sampling personnel.

Table 4.31. Geologic Classification Codes. (Same codes as used for inventory data collection, Table A.9 of the July 2005 revision of the LTPP Inventory Data Collection Guide (19))
DESCRIPTION CODE
Igneous Rock:
Granite 01
Syenite 02
Diroite 03
Gabbro 04
Peridotite 05
Felsite 06
Basalt 07
Diabase 08
Sedimentary Rock :
Limestone 09
Dolomite 10
Shale 11
Sandstone 12
Chert 13
Conglomerate 14
Breccia 15
Metamorphic Rock :
Gneiss 16
Schist 17
Amphibolite 18
Slate 19
Quartzite 20
Marble 21
Serpentine 22
Other Rock Type : (Specify if possible or use the term unknown) 30
Geological Classification of Soils
Glacial Soils 31
Boulder Clay 32
Glacial Sands and Gravels 33
Laminated Silts and Laminated Clays 34
Varved Clays 35
Ground Moraine 36
Fluvio-Glacial Sands and Gravels 37
Other Glacial Soils 38
Plateau Gravels 40
River Gravels 41
Alluvium 42
Alluvial Clays and/or Peat 43
Alluvial Silt 44
Other Alluvial Soils 45
Coastal Shingle and Beach Deposits 46
Wind-Blown Sand 47
Loess (collapsible soil) 48
Shale, Siltstone, Mudstone, Claystone 49
Expansive Soils 50
Residual Soils 51
Residual Soils Derived from Granites, Gneisses, and Schists (maybe highly micaceous and sandy) 52
Residual Soils Developed from Limestone, Sandstone, and Shale (generally highly plastic) 53
Other Residual Soils 54
Coquina 55
Shell 56
Marl 58
Caliche 59
Other (specify if possible or use the term unknown) 60

4.3.8. Pavement Surface Material Type Description (laboratory use)

The pavement surface material type was identified by using the unique two- and three-digit codes listed in Table 4.32.

In this table, AC code 700 represents the general category of AC or bituminous concrete pavements. Codes 01, 02, 03, and 09 through 16 were used for detailed descriptions of AC pavement surface material.

Code 730 was used to define the general category of PCC pavements. Codes 04 through 08 and 17 through 19 were used for detailed descriptions of PCC pavement surface materials.

Laboratory Use

The materials testing laboratories used detailed material descriptions and associated codes if they could make a positive identification. Otherwise, they retained code 700 for AC and code 730 for PCC, as described in the field exploration logs. These codes were to be recorded on Form L05 (Summary of Pavement Layers).

Field Use

Codes 700 (AC pavement) and 730 (PCC pavement) were required to be used on field coreholes, boreholes, shoulder auger probe and test pit exploration logs by the drilling and sampling personnel. These two codes were included in Table 4.25.

Table 4.32. Pavement Surface Material Type Description. (Same Codes 01 through 20 and 71, 72, 73 as used for inventory data collection, Table A.5 of the current revision of the LTPP Inventory Data Collection Guide (19))
MATERIAL TYPE CODE
Asphaltic Concrete (AC) 7001
Hot Mixed, Hot Laid Asphalt Concrete, Dense Graded 01
Hot Mixed, Hot Laid Asphalt Concrete, Open Graded (Porous Friction Course) 02
Sand Asphalt 03
Plant Mix (Emulsified Asphalt) Material, Cold Laid 09
Plant Mix (Cutback Asphalt) Material, Cold Laid 10
Chip Seal 71
Slurry Seal 72
Fog Seal 73
Single Surface Treatment 11
Double Surface Treatment 12
Recycled Asphalt Concrete, Hot Laid, Central Plant Mix 13
Recycled Asphalt Concrete, Cold Laid, Central Plant Mix 14
Recycled Asphalt Concrete, Cold Laid, Mixed-In-Place 15
Recycled Asphalt Concrete, Heater Scarification/Recompaction 16
Portland Cement Concrete (JPCP) 04
Portland Cement Concrete (JRCP) 05
Portland Cement Concrete (CRCP) 06
Portland Cement Concrete (Prestressed) 07
Portland Cement Concrete (Fiber Reinforced) 08
Plain Portland Cement Concrete (only used for SPS-7 overlays of CRCP) 90
Recycled Portland Cement Concrete, JPCP 17
Recycled Portland Cement Concrete, JRCP 18
Recycled Portland Cement Concrete, CRCP 19
Other (Specify if possible or use the term unknown) 20
Portland Cement Concrete (PCC) 7302

1AC - A general term (Code 700) that describes AC layer(s). Code 700 was used for all AC layers (AC, sand asphalt, and other types of surface, wearing and binder courses) in the field data packet received by the laboratory. The laboratory was to provide, if at all possible, a more detailed description using codes 01, 02, 03 and 09 to 16.

2PCC - A general term (Code 730) that describes portland cement concrete layer(s). Code 730 was used for all PCC surface types in the field data packet received by the laboratory. The laboratory was to provide, if at all possible, a more detailed description using codes 04 to 08, 17 and 19.

4.3.9 Portland Cement Types Description (for information only)

Table 4.33 includes codes for portland cement types and descriptions which were used for inventory data collection and site verification.

Table 4.33 was not used by the drilling and sampling personnel in the field, or by the materials testing laboratories.

Table 4.33 was included here for information only.

Table 4.33. Portland Cement Types Description. (Same codes as used for inventory data collection, Table A.11 of the July 2005 revision of the LTPP Inventory Data Collection Guide (FHWA-HRT-06-066).)
TYPE DESCRIPTION CODE
Type I For use when the special properties specified for any other type are not required. (AASHTO M85-84) 41
Type II For general use, more especially when moderate sulfate resistance or moderate heat of hydration is desired. (AASHTO M85-84) 42
Type III For use when high early strength is desired. (AASHTO M85-84) 43
Type IV For use when low heat of hydration is desired. (AASHTO M85-84) 44
Type V For use when high sulfate resistance is desired. (AASHTO M240-85) 45
Type IS Portland blast-furnace slag cement for use in general concrete construction. (AASHTO M240-85) 46
Type ISA Portland blast-furnace slag cement for use in general concrete construction with air-entrainment. (AASHTO M240-85) 47
Type IA Air-entraining cement for the same use as Type I, where air-entrainment is desired. (AASHTO M85-84) 48
Type IIA Air-entraining cement for the same uses as Type II, where air-entraining is desired. (AASHTO M85-84) 49
Type IIIA Air-entraining cement for the same use as Type III, where air-entraining is desired. (AASHTO M85-84) 50
Type IP Portland-pozzolan cement for use in general construction. (AASHTO M240-85) 51
Type IPA Portland-pozzolan cement for use in general concrete construction with air-entrainment. (AASHTO M240-85) 52
Type N Normal hydrated lime portland cement used for masonary purposes. 53
Type NA Normal hydrated lime portland cement used for masonary purposes with 7 - 14% air-entrainment. 54
Other (Specify if possible or use the term unknown) 55

Note: This table is included for information only.

4.3.10. Pavement Type Descriptions (for information only)

Pavement type descriptions and codes included in Table 4.34 were used for inventory data collection and site verification.

Table 4.34 was not used by the drilling and sampling personnel in the field, or by the materials testing laboratories.

Table 4.34 was included here for information only.

Table 4.34. Pavement Type Descriptions. (Same codes as used for inventory data collection, Table A.4 of the July 2005 revision of the LTPP Inventory Data Collection Guide (19).)
TYPE OF PAVEMENT CODE
Asphalt Concrete (AC) Surfaced Pavements:
AC with Granular Base 01
AC with Bituminous Treated Base 02
AC with Non-Bituminous Treated Base 07
AC Overlay on AC Pavement 03
AC Overlay on JPCP Pavement 28
AC Overlay on JRCP Pavement 29
AC Overlay on CRCP Pavement 30
Other (Specify if possible or use the term unknown) 10
Portland Cement Concrete Surfaced Pavements:
JPCP - Placed Directly on Untreated Subgrade 11
JRCP - Placed Directly on Untreated Subgrade 12
CRCP - Placed Directly on Untreated Subgrade 13
JPCP - Placed Directly on Treated Subgrade 14
JRCP - Placed Directly on Treated Subgrade 15
CRCP - Placed Directly on Treated Subgrade 16
JPCP - Over Unbound Base 17
JRCP - Over Unbound Base 18
CRCP - Over Unbound Base 19
JPCP Over Bituminous Treated Base 20
JRCP Over Bituminous Treated Base 21
CRCP Over Bituminous Treated Base 22
JPCP Over Non-Bituminous Treated Base 23
JRCP Over Non-Bituminous Treated Base 24
CRCP Over Non-Bituminous Treated Base 25
JPCP Overlay on JPCP Pavement 31
JPCP Overlay on JRCP Pavement 33
JPCP Overlay on CRCP Pavement 35
JRCP Overlay on JPCP Pavement 32
JRCP Overlay on JRCP Pavement 34
JRCP Overlay on CRCP Pavement 36
CRCP Overlay on JPCP Pavement 38
CRCP Overlay on JRCP Pavement 39
CRCP Overlay on CRCP Pavement 37
JPCP Overlay on AC Pavement 04
JRCP Overlay on AC Pavement 05
CRCP Overlay on AC Pavement 06
Prestressed Concrete Pavement 40
Other (Specify if possible or use the term unknown) 49
*Composite Pavements (Wearing Surface Included in Initial Construction:
JPCP With Asphalt Concrete Wearing Surface 51
JRCP With Asphalt Concrete Wearing Surface 52
CRCP With Asphalt Concrete Wearing Surface 53
Other (Specify if possible or use the term unknown) 59

Definitions:

JPCP - Jointed Plain Concrete Pavement
JRCP - Jointed Reinforced Concrete Pavement
CRCP - Continuously Reinforced Concrete Pavement

* "Composite Pavements" are pavements originally constructed with an asphalt concrete wearing surface over a PCC slab (1986 "AASHTO Guide for Design of Pavement Structures").
Note: This table is included for information only.

4.3.11. Material Codes Used for Interlayers (laboratory use)

The pavement interlayer material type was identified by using the unique two-digit codes listed in Table 4.35.

Laboratory Use

The materials testing laboratories used detailed material descriptions and associated codes if they could make a positive identification. Otherwise, they retain code 700 for AC and code 730 for PCC, as described in the field exploration logs. These codes were recorded on Form L05 (Summary of Pavement Layers).

Field Use

Codes 700 (AC pavement) and 730 (PCC pavement) were used on field coreholes, boreholes, shoulder auger probe and test pit exploration logs by the drilling and sampling personnel. These two codes were included in Table 4.25.

Table 4.35. Material Codes Used for Interlayers. (Same codes as used for inventory data collection, Table A.8 of the July 2005 revision of the LTPP Inventory Data Collection Guide (19).)
MATERIAL TYPE CODE
Grout 70
Chip Seal 71
Slurry Seal 72
Fog Seal 73
Woven Geotextile 74
Nonwoven Geotextile 75
Stress Absorbing Membrane Interlayer 77
Dense Graded Asphalt Concrete Interlayer 78
Aggregate Interlayer 79
Open Graded Asphalt Concrete Interlayer 80
Chip Seal with Modified Binder (Does not include crumb rubber) 81
Sand Seal 82
Asphalt-Rubber Seal Coat 83
Sand Asphalt 84
Other 85

4.3.12 Use of LTPP Terminology and Material Codes in Field Sampling Work

The exploration logs (LTPP field forms S01, S01A, S02A, S02B, S03, and S05) for the field sampling work were filled out using the material terminology and codes described in Table 4.25.

Pavement surface material types were described in the pavement inventory data sheets using the terminology of Table 4.32. On field exploration logs, the general terms 'AC' (asphaltic concrete, material code 700) and 'PCC' (portland cement concrete, material code 730) were used to describe pavement surface materials. AC (material code 700) materials included all HMAC and other types of asphalt surface materials for the purpose of field reports.

The LTPP terminology and codes shown in Table 4.25 were used for the description of base and subbase materials on exploration logs.

Table 4.25 also contained material codes and soils terminology for describing subgrade soils on field exploration logs. These codes were taken from Table 4.26 and used for describing both coarse- and fine-grained subgrade soils.

4.3.13 Use of LTPP Terminology and Material Codes in Laboratory Material Testing Work

The information provided in the above section for pavement surface material type was also applicable in the laboratory material testing work. Form L05 (Summary of Pavement Layer) of the LTPP Laboratory Material Testing Guide required the use of Table 4.32. Tables 4.26 (Subgrade Soils), 4.29 (Base and Subbase Materials), and 4.35 (Interlayer Materials) were also used to complete Form L05.

For treated base and subbase description tests (LTPP Laboratory Protocol P31) the LTPP terminology codes shown in Tables 4.27, 4.29, 4.30 and 4.31 were used.

For unbound granular base and subbase description classification tests (LTPP Laboratory Protocol P47), the LTPP terminology and codes shown in Table 4.29 (based on processing methods), and Table 4.27 (based on ASTM D2488-84) were used. The geologic classification codes of Table 4.31 were also used for the coarse aggregate description of the extracted aggregates from the asphalt extraction test (LTPP Protocol P14).

The LTPP terminology and codes included in Tables 4.26, 4.27 and 4.38 were used to record the laboratory classification test (LTPP Protocol P52) on subgrade soils.

<< PreviousContentsNext >>

The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT).
The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT). Provide leadership and technology for the delivery of long life pavements that meet our customers needs and are safe, cost effective, and can be effectively maintained. Federal Highway Administration's (FHWA) R&T Web site portal, which provides access to or information about the Agency’s R&T program, projects, partnerships, publications, and results.
FHWA
United States Department of Transportation - Federal Highway Administration