Modulus backcalculation methodology based on full-scale testing road and its rationality and feasibility analysis

Abstract

ABSTRACT The objective is to propose a new methodology of modulus backcalculation and analyse its rationality and feasibility. Firstly, the features and advantages of the proposed are summarised. Secondly, a total of 130 sets of deflection basinswere collected and the modulus was backcalculated. Meanwhile, the temperatures of different asphalt layers were monitored. Subsequently, the simple performance test (SPT) was used to establish the master curve model. The dynamic modulus of different asphalt mixtures of falling weight deflector’s load frequency and real test temperature was predicted. Following, the backcalculated modulus was compared with the SPT modulus for verifying its ability of reflecting the material properties. Furthermore, the rationality of the backcalculated modulus is verified, as well as its ability to distinguish between different sections. Lastly, the efficiency, success rate and stability of the proposed method are statistically analysed. Results show that the ratios of the backcalculated modulus to the SPT modulus range from 0.9 to 1.2. The proposed method can process about 100 measured deflection basins per minute and its success rate exceeds 80%. The coefficient of variation of the effective modulus does not exceed 15%. The proposed method has high rationality and feasibility meeting the requirements of engineering applications.