The objective of this technical report is to help road administrations choose and select automated systems in regard to their needs, therefore increasing the quality of the crack data used in pavement management systems. The concepts presented in this document are not international standards, only a summary of the experiences exchanged between world experts. set as its principal objectives the development:
First, the paper presents a series of more objective and more detailed rules to measure and classify cracks. Some have the objective of increasing the reproducibility of measurements and allowing more reliable comparison of the cracking data gathered by different equipment. A monitored zone has been delimited as well as a better definition of a crack and a methodology to measure the crack severity and extent.
Similarly, three methods of evaluation of the reliability of automated crack measuring equipment are also proposed. The research level validation test is used to rate the sensor’s resolution and sensitivity regarding the capability to capture raw pavement data (images or 3D data). The project level validation test allows road administrations to rate the equipment’s bias and repeatability to precisely measure cracks on some small controlled reference track which presents specific and various conditions. While the last validation test, entitled network level validation test, differs from the preceding one by the scope of the measurement campaign and by the precision level sought. Performed on 50-100 km of road, the equipment can be tested on varied surfaces that are more representative of the network reality.
Prepared by Working Group D of Committee TC 4.2 “Road/Vehicle Interaction”