Soil reinforcement with fibers is a simple, efficient and low-cost (especially by incorporating waste or recycled fibers) technique for enhancing mechanical characteristics of soft soils. This experimental study investigates the effects of recycled tire polymer fibers (RTPF) and glass fibers (GF) on enhancing the strength/deformation properties of clays. A series of compaction, unconfined compression and direct shear tests were performed on precisely prepared composite soils comprising clay, with different amounts (i.e. 0.5, 1.0 and 1.5%) of RTPF and GF having varying lengths (5 and 10 mm). Laboratory findings indicated that the composite soils have lower dry density and higher optimum moisture content as compared to the clay. Both unconfined compression and shear strength test results on composite soils implied that while adding fibers increased the materials’ ductility, there was an optimal percentage of fibers (0.5% for RTPF and 1.0% for GF) causing the highest strength gain, beyond which strength decreased. Concerning the shear strength parameters, i.e. cohesion intercept and internal friction angle, the fiber inclusion was particularly influential in increasing cohesion, whereas changes in internal friction angle were minimal. Moreover, the shorter fibers (5 mm) were generally more efficient in reinforcing the clay. The fiber improved composite soils have a better ductility and load-bearing capacity compared to parent soils that can be beneficial in the construction of pavement and railway substructure, liners, small fills/dikes, backfills around pipes, and slope protections.

用纤维进行土壤加固是一种简单，有效且低成本的技术（特别是通过掺入废料或回收纤维）来增强软土的机械特性。这项实验研究调查了再生轮胎聚合物纤维（RTPF）和玻璃纤维（GF）对增强粘土强度/变形性能的影响。在精确制备的包含黏土的复合土壤上进行了一系列压实，无边压缩和直接剪切试验，这些黏土具有不同长度（5和10 mm）的不同含量（即0.5、1.0和1.5％）的RTPF和GF。实验室发现表明，与粘土相比，复合土壤具有较低的干密度和较高的最佳水分含量。复合材料土的无侧限抗压强度和抗剪强度试验结果均表明，虽然添加纤维增加了材料的延展性，但存在最佳百分率的纤维（RTPF为0.5％，GF为1.0％）引起了最高的强度增加，超过此百分比强度下降。关于剪切强度参数，即内聚力拦截和内摩擦角，纤维夹杂物对内聚力的增加特别有影响，而内摩擦角的变化很小。此外，较短的纤维（5毫米）通常在增强粘土方面更有效。与母体土壤相比，纤维改良的复合土壤具有更好的延展性和承重能力，这可能有益于人行道和铁路下部结构，衬砌，小填土/堤防，管道周围回填，