Long Term Pavement Performance Project Laboratory Materials Testing and Handling Guide

Chapter 4. Testing Instructions

This chapter contains the primary information needed to complete the testing of individual samples for the LTPP program. The tables on the following pages provide a list of the protocols included in this chapter and the expected number of tests per layer for each protocol by experiment type. These target levels of testing were not always achieved.

4.1 Laboratory Materials Testing Program

Details of the laboratory material testing program for basic GPS work are provided in Tables 4.1 to 4.6. These tables provide the layer type, test designation, LTPP protocol, and number of tests per layer.

The expected SPS testing for each material are presented by experiment in Tables 4.7 to 4.22. For the experiments involving rehabilitation, there were two rounds of testing performed and these are presented in two separate tables-one for pre-construction and one for post-construction. For the SPS-9A projects, the laboratory testing program was fairly involved. The required tests for these projects are presented across seven tables based on the layers involved and the types of samples being collected.

The MAP provided new target levels for the amount of testing required for some of the tests. The MAP testing program summary is provided in Table 4.23. Initially, the plan identified several new tests to be completed, including the Direct Tension Test, Bending Beam Rheometer (BBR) testing, and Dynamic Shear Test on asphalt cement; petrographic examination of hardened concrete on the PCC layers; and specific gravity and Dynamic Cone Penetrometer (DCP) testing on the unbound materials. Due to budget limitations, only the specific gravity and DCP testing of unbound materials were pursued for additional testing. However, the protocols developed for all of these tests were included in this chapter for informational purposes.

4.2 Protocols

After these tables, the protocols required for laboratory testing are provided. Most of the protocols were modifications of existing AASHTO and ASTM standards. The protocols provided specific directions for performing the tests when the tests were done for the LTPP program. In a few instances, neither AASHTO nor ASTM provided a suitable procedure and therefore a "stand alone" protocol was developed (for example, P01). The protocol and the corresponding AASHTO or ASTM procedure (if applicable) were to be rigorously followed when testing was to be performed for the LTPP program. The protocols are presented in numerical order with the laboratory test data sheets provided directly behind each respective protocol.

Definitions:
NAA - National Aggregate Association

Definitions:

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

Notes:
a Sufficient material should be conditioned for the required tests.

Notes:
a Lab samples were obtained by mixing aggregate stockpile samples with the asphalt cement in accordance with the mix design. Field samples were obtained from bulk samples of the asphalt concrete.

Notes:

1. The cores represented by the number of tests in this table were for each test section to be tested at a specific time interval, t, where t represents the sampling time interval after construction as follows:

t = A at time 0, immediately after construction
t = B at 6 months after construction
t = C at 12 months after construction
t = D at 18 months after construction
t = E at 24 months after construction
t = F at 48 months after construction

All protocols were to be adhered to as standard procedures for the laboratory material testing work. Results from laboratory tests were reported on standard LTPP test forms as provided with each protocol. The pertinent test form number was indicated in the REPORT section of each protocol. In addition, space for comment codes also was included as the second to last item in the REPORT section of each protocol.

The following entries were made on each of the forms in this section: Sheet, Laboratory Performing Test, Laboratory Identification Code, Region, State, Experiment Number, State Code, SHRP ID, Field Set Number, Sampled by, Date Sampled, LTPP Test Designation, LTPP Protocol, Layer Number, Sampling Area No., Laboratory Test Number, Location Number, LTPP Sample Number, Submitted by, Date, Checked and Approved, and Date.

SHEET: All data sheets from the laboratory material testing work on a particular project or test section were assigned sequential numbers starting from 1 for the sample receipt report (Form L01) followed by the sample inspection report (Form L02), preliminary laboratory test assignment (Form L03), laboratory test assignments (Form L04) and so on in increasing order through all of the respective L-type laboratory testing forms and continuing through the T-type laboratory testing forms.

If the information could not be completely filled out on one sheet for one type of sample/test then multiple sheets were used and numbered accordingly ... 1 of 30, 2 of 30, 3 of 30 ....

LABORATORY PERFORMING TEST: The name of the laboratory where the laboratory materials test was conducted was written on this line.

LTPP LABORATORY IDENTIFICATION CODE: The laboratory identification code number assigned to the laboratory performing the test was recorded. The first two digits of the code indicate the state in which the laboratory was operating.

REGION: Identifies the LTPP region in which the project or test section was located:

NA = North Atlantic Region
NC = North Central Region
S = Southern Region
W = Western Region

STATE: Two letter abbreviation (shown in Table 3.2) of the state, District of Columbia, Puerto Rico or the Canadian Province in which the project or test section was located.

EXPERIMENT NO: One of the eight GPS experiments (GPS-1, GPS-2, GPS-3, GPS-4, GPS-5, GPS-6, GPS-7, or GPS-9) or one of the seven SPS experiments (SPS-1, SPS-2, SPS-5, SPS-6, SPS-7, SPS-8 or SPS-9) as shown in Table 3.3 of this Guide.

STATE CODE: Two-digit code as shown in Table 3.2 for the state in which the project or test section was located.

SHRP ID: The four-digit code identifying the specific LTPP test section within the state.

FIELD SET NO: The field set number was a sequentially assigned number to indicate the different time periods in which material samples and field testing were conducted on the project. These time periods usually referred to different stages in the pavement life, such as prior to overlay construction, after overlay construction, end of test, etc. A field set number could have applied to more than one day since sampling of SPS test sections usually required more than one day. As a general rule, the same field set number was applied to all material samples and field tests conducted in a continuous 30-day period, unless a construction event occurred between the two sampling sessions. The number "1" was entered to indicate the first time that material sampling and field testing were conducted on the project.

SAMPLED BY: This was used to identify the Drilling and Sampling Crew who performed the field material sampling and field testing work for this particular project or test section.

DATE (OR DATE SAMPLED): All dates were recorded as mm-dd-yyyy. This date was the date on which the field material sampling and field testing was conducted.

LAYER NUMBER: This item represents the pavement layer number which was assigned by the Participating Laboratory and recorded on Forms L054, L05A, L05B, T01B through T72. This information was based on Field Operations Information Form 2 included in the Field Data Packet received from the Drilling and Sampling Crew, observations of samples in the laboratory packet, inventory data and approval by the Region.

SAMPLING AREA NO: The sampling area number was a two-digit number used to reference all of the samples taken from one area of an SPS project. It has the form SA-##. This number was specified in the materials sampling plan for the project as developed by the LTPP Region.

LABORATORY TEST NUMBER: The number one (1) was used for samples retrieved from locations at Stations 0-. The number two (2) was used for samples retrieved from locations at Stations 5+... The number three (3) was used for samples retrieved from locations within the test section (Stations 0+00 to 5+00). The number four (4) was for samples obtained by combining material from different areas of the test section. The number five (5) was for samples obtained by combining material from multiple test sections. This combining of samples across test sections was required on some SPS projects.

In some tables within the PPDB, laboratory test numbers higher than 5 were used. In these cases, test numbers 6 and 11 have the same meaning as test number 1. Test numbers 7 and 12 have the same meaning as test number 2. Test numbers 8 and 13 have the same meaning as 3. Test numbers 9 and 14 have the same meaning as 4. Test numbers 10 and 15 have the same meaning as 5.

LOCATION NUMBER: This was a three-digit alphanumeric code for the sample location obtained from field markings and Field Operations Information Form 1. This number designated the field location of the sample. Bulk samples may have been combined from several field locations to form a representative sample. See Section 3.2.6 for more information about the location number in these instances.

LTPP SAMPLE NUMBER: This was an alphanumeric four-digit code which had two letters on the left side and two Arabic numerals on the right side which identified the type of sample/specimen and the sampling location of the material sample. Bulk samples may have been combined from several samples to form a representative sample used in testing. See Section 3.2.6 for more information about the sample number identified in these instances.

The first digit on the left was a letter that defines the "sample type." One of the following nine letters was used: C (Core sample), K (Block sample), B (Bulk sample), M (Moisture sample), T (thin-walled tube sample), J (Splitspoon sample), P (chunk and/or broken pieces), F (molded beam), G (molded cylinder).

The second digit from the left end had another letter which indicated the sample material. It may have been one of the following eight letters: A (asphalt concrete), P (portland cement concrete), X (portland cement concrete 14-day test specimens), Y (28-day test specimens), Z (365-day test specimens), T (treated or bound base/subbase), G (granular or unbound base/subbase) and S (subgrade soil). Refer to the Field Sampling Guide for examples and a further explanation of the LTPP sample codes and numbers.⁽²⁾

Sample numbers for each sample retrieved from the field and sent to the Participating Laboratory were found on Field Operations Information Form 1 from the Field Data Packet received from the Drilling and Sampling Crew.

At the bottom of each LTPP Standard Form, the following information was required:

SUBMITTED BY, DATE: The signature (clearly written) of the Laboratory Chief and the date of this signature. Underneath this signature, the corporate affiliation of the Laboratory Chief was identified.

CHECKED AND APPROVED, DATE: The signature (clearly written) of the LTPP Representative who checked and approved the report and the date of this signature. Underneath this signature, the corporate affiliation of the LTPP Representative was identified.