(1. School of Civil Engineering，Wuhan University，Wuhan，Hubei 430072，China；2. Faculty of Engineering，China University of Geosciences，Wuhan，Hubei 430074，China；3. Key Laboratory of Safety for Geotechnical and Structural Engineering of
Hubei Province，Wuhan University，Wuhan，Hubei 430072，China)
Abstract：Clay rock is a common engineering rock mass. Its water-softening and expansion properties are an internal predisposition to geological disasters such as landslides and bank collapses. To understand the water-induced deterioration of mechanical parameters and the propagation of cracks in the process drying-wetting cycles，laboratory test and numerical simulation were carried on. Firstly，a humidity stress transient analysis method based on the water head is proposed. Secondly，a humidity-relative cohesive element was developed. Then，the main parameters are calibrated based on the experimental data. Finally，three loading expansion examples and drying-wetting slake samples of clay rock are simulated by FDEM. The study shows that：(1) the clay rock shows the water-softening property in the process of water-induced expansion. The uniaxial compression strength and elastic modulus of saturated samples are 22% and 25% of dry samples. Therefore，the decrease in strength and rigidity cannot be neglected in the expansive analysis of soft rock. (2) The water-induced expansion of clay rock lags behind the water-softening in history. When the normal pressure is larger than the expansive stress，the confined clay rock always appears in the compression recovery phenomenon. (3) The propagation and coalescence of crack is the main factor inducing slake of clay rock during the drying-wetting cycles. The external crack is easy coalescence and fragment was generated，while the internal crack also causes irreversible damage to the sample. In this study，a new numerical method of shrinkage-expansion analysis is proposed，which plays a guiding role in the engineering calculation in slope，tunnel，and reservoir banks in swelling rock areas.
程树范1，叶 阳2，曾亚武1，3，高 睿1，3，彭志雄1. 干缩、湿胀作用下黏土岩崩解的FDEM模拟[J]. 岩石力学与工程学报, 2023, 42(8): 2068-2080.
CHENG Shufan1，YE Yang2，ZENG Yawu1，3，GAO Rui1，3，PENG Zhixiong1. Numerical simulation research on the slake of clay rocks caused by drying-shrinkage and wetting-expansion based on FDEM. , 2023, 42(8): 2068-2080.
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2023, Vol. 42 
