Performance-based and condition-based NDT for predicting maintenance needs of concrete highways and airport pavements

The state-of-the-art for nondestructive testing (NDT) of highway and airport pavements was evaluated in the late 1980's as part of the Strategic Highway Rehabilitation Program (SHRP). This program included many research projects in pavement construction, testing, maintenance, and rehabilitation. The limitations, as well was the capabilities of the various NDT methods then extant were examined by joint teams of federal, state, academic, and private sector engineers and researchers. The SHRP program, and the allied long-term pavement performance program clearly demonstrated that certain NDT methods performed well on asphalt pavement but performed unsatisfactorily on concrete pavements, and vice-versa. Despite this, some methods are still being used inappropriately, while other promising techniques are virtually being ignored. This paper examines some of the reasons for this, and summarizes the research and current state-of-the-art for NDT of concrete airport and highway pavements. Promising avenues for further development of test equipment, applications, data analysis, and interpretation are also discussed.