In this study, the liquefaction behavior and development laws of pore water pressure in fiber-reinforced sand were studied using cyclic triaxial tests, and the effects of cyclic stress ratio, fiber content, and fiber length were investigated. The test results showed that the cycle number leading to liquefaction and liquefaction resistance increased with fiber content and fiber length, whereas the cycle number leading to liquefaction decreased as the cyclic stress ratio increased. The pore water pressure accumulated more slowly in the fiber-reinforced sand than in the unreinforced sand, and the curves of pore water pressure at low cyclic stress ratio (0.195, 0.203, and 0.230) exhibit three stages, namely a rapidly increasing stage, a slowly increasing stage and a sharply increasing stage. The curves of pore water pressure at high cyclic stress ratio (0.258 and 0.282) exhibited a more varied pattern than those at a low cyclic stress ratio. Based on the test results, a three-parameter pore water pressure model was established considering the effect of cyclic stress ratio, fiber content, fiber length, and sand particle diameter. The predictions agreed relatively well with experimental results, demonstrating that the model can be used to predict pore water pressure in fiber-reinforced sands.

中文翻译：

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基于循环三轴试验的纤维增强砂液化行为

本研究采用循环三轴试验研究了纤维增强砂中孔隙水压力的液化行为和发展规律，并研究了循环应力比、纤维含量和纤维长度的影响。试验结果表明，随着纤维含量和纤维长度的增加，导致液化的循环次数和液化阻力增加，而导致液化的循环次数随着循环应力比的增加而减少。纤维增强砂中孔隙水压力的积累速度比未增强砂中慢，低循环应力比（0.195、0.203和0.230）下的孔隙水压力曲线呈现三个阶段，即快速增加阶段、缓慢增加阶段和急剧增加阶段。高循环应力比（0.258 和 0.282）下的孔隙水压力曲线比低循环应力比下的孔隙水压力曲线表现出更多的变化。根据试验结果，考虑循环应力比、纤维含量、纤维长度和砂粒直径的影响，建立了三参数孔隙水压力模型。预测结果与实验结果比较吻合，表明该模型可用于预测纤维增强砂中的孔隙水压力。