【摘要】 文章以重塑玄武岩残积土为研究对象,采用直剪试验测定了不同干密度、含水率下土体的抗剪强度及其强度指标,得到了黏聚力和内摩擦角随含水率的变化规律;通过滤纸法测定了不同干密度条件下残积土的土水特征曲线,结合直剪试验结果,分析了基质吸力对抗剪强度的影响规律。结果表明:随含水率增大,黏聚力呈先增大后急剧减小趋势,内摩擦角呈逐步减小趋势;在试验所得基质吸力范围内,随基质吸力增大,抗剪强度先增大后不变,非饱和抗剪强度参数φ~b逐步减小且最终趋于0°,即基质吸力对抗剪强度的贡献是有限的;竖向荷载对φ~b有较大的影响,竖向荷载越大,φ~b越大。更多还原

【Abstract】 In order to investigate the influence of water content on cohesion and friction angle,the direct shear tests were adopted to test the shear strength and its index of the remolded unsaturated basalt residual soil under different densities and water content.And filter paper method was used to get the soil-water characteristic curve under different densities.Based on the experimental results of direct shear tests and matric suction tests,the influence of matric suction on the shear strength of the basalt residual soil was analyzed.The results show that the cohesion first increases and drops dramatically,and the friction angle decreases gradually with the increase of water content;within the range of all the matric suction in the test,the unsaturated shear strength parameter φ~b reduces gradually with the increase of the matric suction and ultimately tends to zero,showing that the contribution of matric suction to shear strength is limited;the influence of vertical load on φ~b is obvious,the greater the vertical load,the greater φ~b.更多还原