Forensic Investigation of Pavement: Practices in North America and a Pilot Investigation

Abstract

State agencies/provinces and civil engineers must remain current in forensic pavement investigation procedures and inspection technologies to efficiently maintain public roads. Preliminary pavement investigation procedures typically consist of visual condition surveys and subjective observations. When visual inspections indicate a functional or structural problem may exist, a more refined investigation is necessary. Nondestructive and destructive testing methods, as well as locally documented pavement performance rating data, provide valuable information to further determine the extent of a functional or structural problem. This paper presents a survey of state department of transportation practices to identify the most widely used forensic investigation techniques applied to rigid and flexible pavements. The survey results reveal that falling weight deflectometer (FWD) and ground penetrating radar (GPR) tests are the most commonly used nondestructive evaluation (NDE) techniques for forensic pavement investigation. Finally, a pilot investigation of a jointed plain concrete pavement section was conducted. It was concluded that the forensic pavement investigation procedure recommended by the National Cooperative Highway Research Program (NCHRP) 747 was consistent with the survey results and effective for implementation.