Distress Identification Manual for The Long-Term Pavement Performance Program (Fifth Revised Edition)

CHAPTER 2. DISTRESSES FOR PAVEMENTS WITH JOINTED PORTLAND CEMENT CONCRETE SURFACES

This section covers jointed (plain and reinforced) portland cement concrete-surfaced pavements (JCP), including jointed concrete overlays on PCC pavements. Each of the distresses has been grouped into one of the following categories:

Cracking. Joint deficiencies. Surface defects. Miscellaneous distresses.

 

 

 

 

Table 2 summarizes the various types of distress and unit of measurement. Some distresses also have defined severity levels.

Table 2. JCP Distress Types.

A. CRACKING

This section includes the following types of distresses:

  1. Corner breaks.

  2. Durability cracking ("D" cracking).

  3. Longitudinal cracking.

  4. Transverse cracking.

Figure 47 illustrates the proper measurement of crack width and width of spalling for cracks and joints.

Figure 47. Measuring Widths of Spalls and Cracks in JCP

1. Corner Breaks

Description

A portion of the slab is separated by a crack, which intersects the adjacent transverse and longitudinal joints, describing approximately a 45-degree angle with the direction of traffic. The length of the sides is from 0.3 m to half the width of the slab on each side of the corner.

Severity Levels

Low:

The crack is not spalled for more than 10 percent of the length of the crack. There is no measurable faulting, and the corner piece is not broken into two or more pieces and has no loss of material and no patching.

Moderate:

The crack is spalled at low severity for more than 10 percent of its total length or faulting of the crack or joint is < 13 mm and the corner piece is not broken into two or more pieces.

High:

The crack is spalled at moderate to high severity for more than 10 percent of its total length or faulting of the crack or joint is ≥ 13 mm, or the corner piece is broken into two or more pieces or contains patch material.

How to Measure

Record the number of corner breaks at each severity level. Corner breaks that have been repaired by completely removing all broken pieces and replacing them with patching material (rigid or flexible) should be rated as a patch. If the boundaries of the corner break are visible, then also rate it as a high severity corner break. Note: This does not affect the way patches are rated. All patches meeting the size criteria are rated.

Figure 48. Distress Type JCP 1-Corner Breaks

Figure 49. Distress Type JCP 1-Low Severity Corner Break

Figure 50. Distress Type JCP 1-Moderate Severity Corner Break

2. Durability Cracking ("D" Cracking)

Description

Closely spaced crescent-shaped hairline cracking pattern.

Occurs adjacent to joints, cracks, or free edges and initiates in slab corners. Dark coloring of the cracking pattern and surrounding area.

How to Measure

Record the number of slabs with "D" cracking and square meters of area affected at each severity level. The slab and affected area severity rating is based on the highest severity level present for at least 10 percent of the area affected.

Severity Levels

Low:

"D" cracks are tight, with no loose or missing pieces, and no patching is in the affected area.

Moderate:

"D" cracks are well-defined, and some small pieces are loose or have been displaced.

High:

"D" cracking has a well-developed pattern, with a significant amount of loose or missing material. Displaced pieces up to 0.1 m² may have been patched.

Figure 51. Distress Type JCP 2- "D" Cracking

Figure 52. Distress Type JCP 2- Moderate Severity "D" Cracking with Well-Defined Pattern

Figure 53. Distress Type JCP 2-High Severity "D" Cracking with Loose and Missing Material

3. Longitudinal Cracking

Description

Cracks that are predominantly parallel to the pavement centerline.

Severity Levels

Low:

Crack widths < 3 mm with no spalling and no measurable faulting or well-sealed cracks with a width that cannot be determined.

Moderate:

Crack widths ≥ 3 mm and < 13 mm; or with spalling < 75 mm; or faulting up to 13 mm.

High:

Crack widths ≥ 13 mm; or with spalling ≥ 75 mm; or faulting ≥ 13 mm.

Figure 54. Distress Type JCP 3-Longitudinal Cracking

How to Measure

Record the length in meters of longitudinal cracking at each severity level. Also record the length in meters of longitudinal cracking with sealant in good condition at each severity level. Sealant is not considered to be in good condition unless at least 1 m of continuous sealant in good condition is present. In cases where a crack is less than 1 m long, the sealant must be present and in good condition over the entire length of the crack. When a crack is within 0.3 m of a joint for only a portion of its length, it should be recorded as a spall only for that portion so long as that portion is at least 0.3 m long. The portion of the crack that is greater than 0.3 m from the joint should be recorded as a longitudinal crack.

Figure 55. Distress Type JCP 3-Low Severity Longitudinal Cracking

Figure 56. Distress Type JCP 3-Moderate Severity Longitudinal Cracking

Figure 57. Distress Type JCP 3-High Severity Longitudinal Cracking

4. Transverse Cracking

Description

Cracks that are predominantly perpendicular to the pavement centerline.

Severity Levels

Low:

Crack widths < 3 mm with no spalling and no measurable faulting or cracks that are well-sealed with an undetermined width.

Moderate:

Crack widths ≥ 3 mm and < 6 mm; or with spalling < 75 mm; or faulting up to 6 mm.

High:

Crack widths ≥ 6 mm; or with spalling ≥ 75 mm; or faulting ≥ 6 mm.

Figure 58. Distress Type JCP 4-Transverse Cracking

How to Measure

Record the number and length of transverse cracks at each severity level. Rate the total length of the transverse crack at the highest severity level present for at least 10 percent of the length of the crack.

Also record the length of the transverse cracking at each severity level with sealant in good condition. The total length of the well-sealed crack is assigned to the severity level of the crack. Record only when the sealant is in good condition for at least 90 percent of the length of the crack. When a crack is within 0.3 m of a joint for only a portion of its length, it should be recorded as a spall only for that portion so long as that portion is at least 0.3 m long. The portion of the crack that is greater than 0.3 m from the joint should be recorded as a transverse crack.

Figure 59. Distress Type JCP 4-Moderate Severity Transverse Cracking

Figure 60. Distress Type JCP 4-High Severity Transverse Cracking

B. JOINT DEFICIENCIES

This section includes the following types of distresses:

    5. Joint seal damage.

        5a. Transverse joint seal damage.

        5b. Longitudinal joint seal damage.

    6. Spalling of longitudinal joints.

    7. Spalling of transverse joints.

5. Joint Seal Damage

Description

Joint seal damage is any condition that enables incompressible materials or a significant amount of water to infiltrate the joint from the surface. Typical types of joint seal damage include extrusion, hardening, adhesive failure (bonding), cohesive failure (splitting), complete loss of sealant, intrusion of foreign material into the joint or grass or weed growth in the joint.

5a. Transverse Joint Seal Damage

Severity Levels

Low:

Joint seal damage exists in less than 10 percent of the joint.

Moderate:

Joint seal damage exists in 10 to 50 percent of the joint.

High:

Joint seal damage exists over more than 50 percent of the joint.

Figure 61. Distress Type JCP 5-Low Severity Joint Seal Damage

How to Measure

Indicate whether the transverse joints have been sealed (yes or no). If yes, record the number of sealed transverse joints at each severity level. Any joint seal with no apparent damage is considered to be low severity.

Note: That portion of a joint with spot patching in good condition (i.e., no defects) is considered well sealed. Patches are rated separately.

5b. Longitudinal Joint Seal Damage

Severity Levels

None.

How to Measure

Record the number of longitudinal joints that are sealed (0, 1, 2). Record the total length of sealed longitudinal joints with joint seal damage. Individual occurrences are recorded only when at least 1 m long.

Note: That portion of a joint with spot patching in good condition (i.e., no defects) is considered well sealed. Patches are rated separately.

Figure 62. Distress Type JCP 5-Moderate Severity Joint Seal Damage

6. Spalling of Longitudinal Joints

Description

Cracking, breaking, chipping, or fraying of slab edge within 0.3 m from the face of the longitudinal joint.

Severity Levels

Low:

Spalls < 75 mm wide measured to the face of the joint with loss of material and no patching or spalls with no loss of material and no patching.

Moderate:

Spalls 75 to 150 mm wide measured to the face of the joint with loss of material.

High:

Spalls > 150 mm wide measured to the face of the joint with loss of material or spalls broken into two or more pieces or spalls containing patch material.

How to Measure

Record the length of longitudinal joint affected at each severity level. Only record spalls that have a length of 0.1 m or more. Spalls that have been repaired by completely removing all broken pieces and replacing them with patching material (rigid or flexible) should be rated as a patch. If the boundaries of the spall are visible, then also rate as a high severity spall. When a crack is within 0.3 m of a joint for only a portion of its length, it should be recorded as a spall only for that portion so long as that portion is at least 0.3 m long. The portion of the crack that is greater than 0.3 m from the joint should be recorded as a longitudinal or transverse crack as appropriate.

Figure 63. Distress Type JCP 6-Spalling of Longitudinal Joints

Figure 64. Distress Type JCP 6-Low Severity Spalling of Longitudinal Joint

Figure 65. Distress Type JCP 6-High Severity Spalling of Longitudinal Joint

7. Spalling of Transverse Joints

Description

Cracking, breaking, chipping, or fraying of slab edges within 0.3 m from the face of the transverse joint.

Severity Levels

Low:

Spalls < 75 mm wide measured to the face of the joint with loss of material and no patching or spalls with no loss of material and no patching.

Moderate:

Spalls 75 to 150 mm wide measured to the face of the joint with loss of material.

High:

Spalls > 150 mm wide measured to the face of the joint with loss of material, or spalls broken into two or more pieces, or spalls containing patch material.

Figure 66. Distress Type JCP 7-Spalling of Transverse Joints

How to Measure

Record the number of affected transverse joints at each severity level. A joint is affected only if the total length of spalling is 10 percent or more of the length of the joint. Rate the entire transverse joint at the highest severity level present for at least 10 percent of the total length of the spalling. Record length in meters of the spalled portion of the joint at the assigned severity level for the joint. Spalls that have been repaired by completely removing all broken pieces and replacing them with patching material (ridged or flexible) should be rated as a patch. If the boundaries of the spall are visible, then also rate as a high severity spall. When a crack is within 0.3 m of a joint for only a portion of its length, it should be recorded as a spall only for that portion, so long as that portion is at least 0.3 m long. The portion of the crack that is greater than 0.3 m from the joint should be recorded as a longitudinal or transverse crack as appropriate.

Figure 67. Distress Type JCP 7-Moderate Severity Spalling of Transverse Joint, Far View

Figure 68. Distress Type JCP 7-Moderate Severity Spalling of Transverse Joint, Close-up View

C. SURFACE DEFECTS

This section includes the following types of distresses:

    8. Map cracking and scaling.

        8a. Map cracking.

        8b. Scaling.

    9. Polished aggregate.

    10. Popouts.

8. Map Cracking and Scaling

8a. Map Cracking

Description

A series of cracks that extend only into the upper surface of the slab. Larger cracks are frequently oriented in the longitudinal direction of the pavement and are interconnected by finer transverse or random cracks.

Severity Levels

Not applicable.

How to Measure

Record the number of occurrences and the square meters of affected area.

Figure 69. Distress Type JCP 8a-Map Cracking

8b. Scaling

Description

Scaling is the deterioration of the upper concrete slab surface, normally 3 to 13 mm, and may occur anywhere over the pavement.

Severity Levels

Not applicable.

How to Measure

Record the number of occurrences and the square meters of affected area.

Figure 70. Distress Type JCP 8b-Scaling

Figure 71. Distress Type JCP 8b-Scaling, Close-up View

9. Polished Aggregate

Description

Surface mortar and texturing worn away to expose coarse aggregate.

Severity Levels

Not applicable. However, the degree of polishing may be reflected in a reduction of surface friction.

How to Measure

Record the square meters of affected surface area.

Note: Diamond grinding also removes the surface mortar and texturing. However, this condition should not be recorded as polished aggregate. Instead, it should be noted by a comment.

Figure 72. Distress Type JCP 9-Polished Aggregate

10. Popouts

Description

Small pieces of pavement broken loose from the surface, normally ranging in diameter from 25 to 100 mm and in depth from 13 to 50 mm.

Severity Levels

Not applicable. However, severity levels can be defined in relation to the intensity of Popouts as measured below.

How to Measure

Not recorded in LTPP surveys, but should be noted.

Figure 73. Distress Type JCP 10-Popouts

Figure 74. Distress Type JCP 10-A Popout

D. MISCELLANEOUS DISTRESSES

This section includes the following distresses:

    11. Blowups.

    12. Faulting of transverse joints and cracks.

    13. Lane-to-shoulder dropoff.

    14. Lane-to-shoulder separation.

    15. Patch/patch deterioration.

    16. Water bleeding and pumping.

11. Blowups

Description

Localized upward movement of the pavement surface at transverse joints or cracks, often accompanied by shattering of the concrete in that area.

Severity Levels

Not applicable. However, severity levels can be defined by the relative effect of a blowup on ride quality and safety.

How to Measure

Record the number of blowups.

Figure 75. Distress Type JCP 11-Blowups

Figure 76. Distress Type JCP 11-A Blowup

12. Faulting of Transverse Joints and Cracks

Description

Difference in elevation across a joint or crack.

Severity Level

Not applicable. Severity levels could be defined by categorizing the measurements taken. A complete record of the measurements taken is much more desirable, however, because it is more accurate and repeatable than severity levels.

How to Measure

Record, to the nearest millimeter: 0.3 and 0.75 m from the outside slab edge (approximately the outer wheel path). For a widened lane, the wheel path location will be 0.75 m from the outside lane edge stripe. If the approach slab is higher than the departure slab, record faulting as positive; if the approach slab is lower, record faulting as negative.

Faulting on PCC pavements is to be measured using an FHWA-modified Georgia faultmeter. A representative reading from three distinct measurements at each location is to be used and recorded on sheet 6.

When anomalies such as patching, spalling, and corner breaks are encountered, the faultmeter should be offset to avoid the anomaly. The maximum offset is 0.3 m. A null value should be recorded and entered into the database when the surveyor is unable to take a measurement due to an anomaly.

Figure 77. Distress Type JCP 12-Faulting of Transverse Joints and Cracks

Surveyors must ensure that they have a working faultmeter with fully charged batteries prior to beginning a survey on a jointed PCC test section. Complete faulting measurements and survey sheet 6 at the beginning of the distress survey to ensure that this data is collected.

Point distance measurements entered on sheet 6 for joints and transverse cracks should be consistent between surveys of the same test section to an accuracy of less than 0.5 m. Evaluate newly observed distresses and point distance differences for previously identified distresses of 0.5 m and greater with a metric tape measure.

Figure 78. Distress Type JCP 12-Faulting of Transverse Cracks

13. Lane-to-Shoulder Dropoff

Description

Difference in elevation between the edge of slab and outside shoulder; typically occurs when the outside shoulder settles.

Severity Levels

Not applicable. Severity levels can be defined by categorizing the measurements taken. A complete record of the measurements taken is much more desirable, however, because it is more accurate and repeatable than severity levels.

How to Measure

Measure at the longitudinal construction joint between the lane edge and the shoulder.

Record to the nearest millimeter at 15.25-m intervals along the lane-to-shoulder joint.

If the traveled surface is lower than the shoulder, record as a negative value.

Figure 79. Distress Type JCP 13-Lane-to-Shoulder Dropoff

Figure 80. Distress Type JCP 13- Lane-to-Shoulder Dropoff

14. Lane-to-Shoulder Separation

Description

Widening of the joint between the edge of the slab and the shoulder.

Severity Levels

Not applicable. Severity levels can be defined by categorizing the measurements taken. A complete record of the measurements taken is much more desirable, however, because it is more accurate and repeatable than severity levels.

How to Measure

Record to the nearest millimeter at intervals of 15.25 m along the lane-to-shoulder joint. Indicate whether the joint is well-sealed (yes or no) at each location.

Note: A null value should be recorded and entered into the database when the surveyor is unable to take a measurement due to an anomaly such as sealant or patch material.

Figure 81. Distress Type JCP 14-Lane-to-Shoulder Separation

Figure 82. Distress Type JCP 14-Poorly Sealed Lane-to-Shoulder Separation

Figure 83. Distress Type JCP 14-Well-Sealed Lane-to-Shoulder Separation

15. Patch/Patch Deterioration

Description

A portion (greater than or equal to 0.1 m²) or all of the original concrete slab that has been removed and replaced or additional material applied to the pavement after original construction.

Severity Levels

Low:

Patch has, at most, low severity distress of any type, no measurable faulting or settlement, and there is no loss of patching material. Pumping is not evident.

Moderate:

Patch has moderate severity distress of any type or faulting or settlement up to 6 mm. Pumping is not evident.

High:

Patch has a high severity distress of any type; or, faulting or settlement is ≥ 6 mm, or the patch has additional material within it. Pumping may be evident.

Figure 84. Distress Type JCP 15-Patch/Patch Deterioration

Figure 85. Distress Type JCP 15-Small, Low Severity AC Patch

How to Measure

Record the number of patches and square meters of affected surface area at each severity level by material type-rigid versus flexible. For slab replacement, rate each slab as a separate patch and continue to rate joints. Note: Surface flexible patches are limited to those with patching material that contain aggregate. If a surface patch has worn away revealing an underlying distress or if the underlying distress has reflected through the surface patch and the distress’ existence can be verified on prior surveys, then also rate the distress. Any new distress in the original pavement layer in the patched area should also be rated. Distresses in the patched area affect the severity level of the patch. Patches with no distress are rated low severity. Applications of sealant without aggregate are not to be recorded as patches. These should be drawn on the map sheets and recorded on the distress survey sheets as distress type 17 Other provided that they exceed 0.1 m².

Figure 86. Distress Type JCP 15-Large, Low Severity AC Patch

Figure 87. Distress Type JCP 15-Large, High Severity AC Patch

Figure 88. Distress Type JCP 15-Large, Low Severity PCC Patch

16. Water Bleeding and Pumping

Description

Seeping or ejection of water from beneath the pavement through cracks or joints. In some cases, detectable by deposits of fine material left on the pavement surface, which were eroded (pumped) from the support layers and have stained the surface.

Severity Levels

Not applicable. Severity levels are not used because the amount and degree of water bleeding and pumping changes with varying moisture conditions.

How to Measure

Record the number of occurrences of water bleeding and pumping and the length of affected pavement with a minimum length of 1 m.

Note: Water bleeding and pumping are measured longitudinally along the length of the test section. The combined length of water bleeding and pumping cannot exceed the length of the test section.

Figure 89. Distress Type JCP 16-Water Bleeding and Pumping