Comparison of Overlay Design in Between Lightweight Deflectometer and Benkelman Beam Deflection Test Results: A Case Study in India

Abstract

AbstractStrengthening is an essential aspect of the operation, maintenance and management of low volume roads. In India, maintenance of other districts roads and village roads is a very significant task. Benkelman Beam Deflection (BBD) method is laborious and time-consuming because of the state of practice. However, the state-of-art Lightweight Deflectometer (LWD) method was employed to overlay the thickness design of low volume roads (LVR), utilizing a rationale that accounts for the determination of dynamic deflections of thin paved surfaces. This paper aimed to look into the behavior of in-service low-volume roads at a project level and develop a simplified method of designing overlay thickness for low-volume roads using two NDT methods. The results were compared and correlated for low volume roads (LVR). In this paper, responsive stress and strain of thin asphalt pavement beneath layers were analyzed using KENPAVE software. The overlay thickness for different sections ranges from 27.00 mm to 184.39 mm by LWD and BBD. The correlation for deflection values between LWD and BBD was R2 (0.741), while the overlay thickness designed by LWD and BBD showed a high correlation with R2 value of 0.994. This paper also serves to assess the capability of LWD to serve as a substitute to traditional BBD on low volume roads (LVR). The practical limitation of BBD test procedure and analysis may be overcome by conducting more test points using LWD on Indian thin asphalt low volume roads. KeywordsLVRLWDBBDOverlay thickness