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| Experimental study of dynamic shear moduli and microscopic-pore structure of soft clay |
| MO Haihong1，2，SHAN Yi1，2，3，MA Hao3，4，CHEN Junsheng1，2 |
(1. School of Civil Engineering and Transportation，South China University of Technology，Guangzhou，Guangdong 510641，China；
2. State Key Laboratory of Subtropical Building Science，South China University of Technology，Guangzhou，Guangdong 510641，China；3. Department of Civil Engineering，Shantou University，Shantou，Guangdong 515063，China；
4. China Light Industry Wuhan Design and Engineering Co.，Ltd.，Wuhan，Hubei 430060，China) |
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Abstract In order to quantitatively analyze the dynamic shear modulus from the perspective of micro soil structure，relationships between the dynamic shear modulus and the intergranular void of remolded soft clay from Eastern Guangdong are studied from both macroscopic and microcosmic aspects using the resonant column test，the scanning electron microscope test and the microscopic-pore structure analysis method. According to the three-parameter Davidenkov model-based nonlinear regression analysis and the parameters analysis of microscopic-pore structure，the effective stress was found to increase and the wave velocity to accelerate after the consolidation process and thus maximum dynamic shear modulus became larger. The macro void ratio of soil decreased. The intergranular void layers grew and the fractal dimension of porous perimeter-area increased. The degree of void homogenization increased and the porous fractal dimension value decreased. The study demonstrates the correlation between the three parameters of Davidenkov model(initial parameter，range parameter and rate parameter) and the microscopic-pore structure parameters.
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2016, Vol. 35 
