海相软土力学性能参数对滨海城市地下工程的设计和施工而言至关重要。采用颗粒离散元分析方法,建立了海相软土三轴试验离散元数值计算模型,通过模拟其三轴试验过程并与室内试验进行对比验证。结果表明:海相软土室内试验的轴向应变发展类型为渐稳发展型,累计轴向应变随着振动次数的增加逐渐增大;摩擦系数、黏结强度等因素对累积塑性应变的影响都较为明显,较高的摩擦系数会导致颗粒之间的内摩擦力更大,从而使试样更不易变形;摩擦系数对累积塑性应变的影响最为明显;相较于法向黏结强度,切向黏结强度对试样塑性应变的影响更为明显;切向黏结强度控制颗粒之间的相对滑动,较高的切向黏结强度会使颗粒更难发生相对滑动。
The mechanical performance parameters of marine soft soil are crucial for the design and construction of underground engineering in coastal cities. To address this, a granular discrete element analysis method was employed to establish a numerical model for the triaxial tests of marine soft soil. The model was validated by simulating the triaxial test process and comparing it with indoor experiments. The research results show that: The indoor axial strain development of marine soft soil follows a gradually stable pattern, with cumulative axial strain gradually increasing with the number of vibrations. Factors such as friction coefficient and cohesive strength have a significant impact on cumulative plastic strain. A higher friction coefficient results in greater internal frictional force between particles, making the specimen more resistant to deformation. The influence of the friction coefficient on cumulative plastic strain is particularly pronounced. Compared to the normal bond strength, the tangential bond strength has a more significant effect on the plastic strain of the specimen. Higher tangential bond strength controls the relative sliding between particles, making it more difficult for particles to undergo relative sliding.
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