棕榈加筋土抗剪强度的影响因素分析

Analysis on influence factors of shear strength of palm reinforced soil

为了较为全面研究不同影响因素对棕榈加筋黏土的抗剪强度的影响程度,选取长度为2和8 mm的棕榈片,并以不同质量加筋率(0.25%、0.50%、1.0%、2.0%)和长宽比(1∶1、1∶2、1∶3、1∶4)加入到黏土中,对棕榈加筋土进行直接慢剪试验。试验结果表明:棕榈可以提高上海黏土的抗剪强度和土体的黏聚力,对内摩擦角基本无影响;直剪慢剪试验中,两种尺寸下的筋材的最优加筋率均为0.50%,最佳筋材长宽比为1∶3;棕榈长度为8 mm的加筋土抗剪强度峰值和黏聚力均优于2 mm的加筋土;指出了棕榈加筋土在研究领域的不足并提出目前在实际工程上面临的难题。

For a more comprehensive study on the influence of different factors on the shear strength of palm reinforced clay,the paper selected palm sheets with lengths of 2mm and 8mm and added different mass ratios（ 0. 25%,0. 50%,1. 0%,2. 0%） and aspect ratio（ 1∶ 1,1∶ 2,1∶ 3,1∶ 4） into the clay. A slow shear test was measured to palm reinforced soil directly. The results showed that palm can improve the cohesion and shear strength of clay soil in Shanghai,meanwhile palm has no influence on internal friction angle; in the direct shear test,the optimal reinforcement is 0. 50% and the best aspect ratio is 1∶ 3; The peak shear strength and cohesion of the palm with length of 8mm are both better than the one with 2mm long. The paper pointed out the short of palm reinforced soil as well as the practical engineering problems faced at present.