Soil reinforcement with natural or synthetic fibers enhances its mechanical behavior in various applications. Fiber-reinforced sands (FRS) can be relatively anisotropic because of the fiber self-weight and the compaction technique. However, the microscopic mechanisms underlying the anisotropy are still poorly understood. This study used a discrete element approach to analyze the microscopic mechanisms underlying the strength anisotropy of FRS due to fiber orientation. Analysis of contact networks revealed that the optimum fiber orientation angle is perpendicular to the main direction of strong contact force in direct shear testing. These fibers produced the largest increase in shear zone thickness, normal force around the fiber body, effective contact area, tensile force along fibers, and energy storage/dissipation. This study is valuable for further understanding of the mechanical behaviors of FRS.

中文翻译：

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直剪载荷作用下纤维增强砂强度各向异性的离散元分析

用天然或合成纤维加固土壤可增强其在各种应用中的机械性能。纤维增强砂（FRS）由于纤维自重和压实技术而可能相对各向异性。但是，对各向异性的微观机理仍知之甚少。这项研究使用离散元素方法分析了由于纤维取向而导致FRS强度各向异性的微观机理。接触网络分析表明，在直接剪切试验中，最佳纤维取向角垂直于强接触力的主方向。这些纤维在剪切区厚度，纤维体周围的法向力，有效接触面积，沿纤维的拉伸力以及能量存储/耗散方面增加最大。