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 are severity levels.
How to Measure
Record in millimeters, to the nearest millimeter: 0.3 m 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. At each location, three measurements are made, but only the approximate average of the readings is recorded.
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 a 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 cornerbreaks are encountered, the faultmeter should be offset to avoid the anomaly. The maximum offset is 0.3 m.
A null value (“N”) should be recorded and entered into the database when the surveyor is unable to take a measurement due to an anomaly.
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. Note: The precise start point of surveys must be clearly identified in the field.