Cracking and Surface Distress

Cracking and surface distress.

Specifications developed by Austroad for automatic crack detection and high speed deflectometer data collection.

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” 

The objective of this technical report is to help road administrations to choose and select automated systems in regard of their needs and to increase the quality of the crack data used in pavement management systems. The concepts presented in this document are not international standards but only a summary of the experience exchanges between world experts.
Paper describing an evaluation of automated crack detection.
Report evaluating whether a practical method of road surface texture measurement using information theory and fast Fourier transformation analysis could be developed.
Guides to conducing the UK SCANNER (Surface Condition Assessment of the National Network of Roads) surveys. Specification for Services with details on survey procedures, data processing, route fitting and calculations of derived parameters.
Guides to conducing the UK SCANNER (Surface Condition Assessment of the National Network of Roads) surveys. Quality Assurance and Audit with procedures to ensure Services are consistent and reliable. Includes audit processes, monitoring, calibration, and requirements for repeat surveys.
Guides to conducing the UK SCANNER (Surface Condition Assessment of the National Network of Roads) surveys. Technical Guidance on interpretation of processed SCANNER data.
Guides to conducing the UK SCANNER (Surface Condition Assessment of the National Network of Roads) surveys. Gives background infromation on the development of SCANNER surveys, advice on contract procurement and mobilization, glossary of technical tems and a model contract document as annexes.
Guides to conducing the UK SCANNER (Surface Condition Assessment of the National Network of Roads) surveys. Acceptance Testing and Accreditation describes the requirements for testing survey vehicles to become accredited by site and network tests. It also describes the requirements for the reporting and delivey of survey data.
NHCRP Synthesis 334 describing various techniques for automated collection of surface distress data
Report describing how the data from a pavement management system were converted for use with HDM pavement deterioration model
Paper by Bill Paterson describing the Universal Cracking Index, a way of measuring cracking. The UCI has been implemented by some automated crack analysis software systems.
Internal paper by W.D.O. Paterson of the World Bank introducing the concept of the SII and how it is used in the field