Modified Duncan-Chang model considering disturbance
XU Ri-qing1, ZHANG Jun1, ZHU Jian-feng1,2, WANG Xing-chen1
1. Key Laboratory of Soft Soils and Geoenvironmental Engineering, Ministry of Education, Zhejiang University,
Hangzhou 310058,China; 2. Faculty of Architectural Civil Engineering and Environment, Ningbo University,
Ningbo 315211, China
The triaxial test data of ISO standard sand of China under different conditions show that the relative density strongly affect the strength-deformation property of sand. The general disturbance function was proposed based on the disturbed state concept (DSC). The function considered the relative density of sand as the disturbed parameter. Then the modified Duncan-Chang model, which could reflect the contribution of disturbance to the strength-deformation property of sand, was developed through establishing the relationship between parameters K and peak strength and disturbed degree. The material parameters d、g and the parameters of Duncan-Chang model at initial state were given. Then the stress-strain relation of sand at randomly disturbed state can be predicted by the modified model. The test results show that the modified Duncan-Chang model can well describe the stress-strain relation of sand at a given disturbed state.
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