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

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.

KEYWORDS:

• Modulus backcalculation
• full-scale testing road
• simple performance test
• master curve
• rationality
• feasibility

Acknowledgements

Chunlong Xiong and Xiaoning Zhang conceptualised the data; Chunlong Xiong and Shekhovtsova Svetlana curated the data; Chunlong Xiong, Evgeniy Korolev, E. Yang and Jiangmiao Yu performed the formal analysis; Jiangmiao Yu and Bo Chen have made substantial contributions to acquisition of funding; Chunlong Xiong, Bo Chen and E. Yang investigated; Chunlong Xiong has helped with writing the original draft; Chunlong Xiong and Jiangmiao Yu have made substantial contributions to writing, reviewing and editing the article. The authors also want to appreciate the support of South China University of Technology, Xiaoning Roadway Institute of Engineering and Research Institute of Highway Ministry of Transport of China.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors sincerely acknowledge the support of the National Natural Science Foundation of China [grant number NSFC 51678251], [grant number NSFC 52178426]; China Postdoctoral Science Foundation Project [grant number 2020M672639].