Applied Non-Destructive Tests to Synthetically Investigate the Bearing Capacity Loss of Pavement

Abstract

This study was set out to analyze and investigate the damaged surface course of a newly-constructed road pavement within the two years after its completion. Because the idea of sustainable public infrastructure in Taiwan has recently encouraged the use of renewable materials in the design phase, parts of this roads pavement structure is composed of recycled asphalt concrete, renewable agents, disposed construction surplus and the like. Considering the complex relationship between the damaged condition of the road pavement and factors such as its load repetitions, its design, its construction process and management, and road management, this study employed an intelligent vehicle for pavement survey, Benkelman Beam method, GeoGauge, and Ground Penetrating Radar to examine the roads pavement structure. After cross-analyzing the results from the non-destructive testing, certain parts of the road and the possibly-damaged structure of the pavement were sampled for material testing. The results from the material testing indicated that the related mechanical parameters of the road sections sampled by the non-destructive testing were significantly lower than the normal standards. Moreover, the results from the GPR analysis revealed that the water content of the subgrade of the severely-damaged road sections was high. The low loading capacity of the pavement structure was mainly due to the high groundwater water level in the surrounding area and the penetration of the rain into the cracks of the surface course. This study proposes that nondestructive testing can facilitate sampling sections for material testing to better ensure the quality of the construction although random sampling is commonly seen in the standard material testing for acceptance of completed work. In addition, the study suggests that non-destructive testing can be one requirement for the acceptance of completed work in pavement projects with renewable materials to better evaluate the quality of the pavement after its construction.