论文部分内容阅读
为了揭示石灰和硅灰胶结超盐渍土的抗剪强度规律,对采自宁夏平罗县姚伏镇的超盐渍土分别掺入硅灰和石灰进行超盐渍土固化,其中,硅灰掺量分别为1%、3%、5%,石灰掺量分别为硅灰掺量的20%、40%、60%。并利用三轴仪对7、28 d龄期固化的超盐渍土进行抗剪强度指标测定。试验结果表明:7 d龄期,1%硅灰掺量的固化超盐渍土的摩擦角随石灰掺量的增加呈现先增加后减小的变化趋势,28d龄期,1%硅灰掺量的超盐渍土的摩擦角随石灰掺量的增加而减小;7、28 d龄期,3%、5%硅灰掺量的固化超盐渍土的摩擦角和黏聚力随着石灰掺量的增加而增加。鉴于超盐渍土的抗剪强度由摩擦角和黏聚力共同决定,而随硅灰和石灰掺量的增加,固化超盐渍土的摩擦角和黏聚力的变化趋势不一致,为了易于确定固化超盐渍土中硅灰和石灰土最佳掺量,文中给出了抗剪强度临界深度的判断公式,可依据判别公式来确定硅灰和石灰的最佳掺量。
In order to reveal the law of shear strength of limestone and silicified cement super-saline soil, the ultra-saline soil collected from Yao-vu town, Pingluo County, Ningxia were respectively mixed with silica fume and lime for super-saline soil solidification. The content of lime were 1%, 3% and 5% respectively, and the content of lime was 20%, 40% and 60% respectively. The triaxial apparatus was used to measure the shear strength index of the over saline saline soil aged 7,28 days. The results show that the friction angle of the solidified hypersaline saline soil with 1% silica fume increases firstly and then decreases with the increase of lime content at 7 d, The friction angle and the cohesion of solidified hypersaline saline soil with 3% and 5% silica fume at 7 and 28 d, respectively, increased with the increase of lime content. With the increase of lime content, Increasing the amount of increase. As the shear strength of the ultra-saline soil is determined by both the friction angle and the cohesion force, the variation tendency of the friction angle and the cohesion of the solidified ultra-saline soil is not consistent with the increase of silica fume and lime content. The optimum dosage of silica fume and lime soil in solidified salinized soil is given in this paper. The judgment formula of the critical depth of shear strength is given in this paper. The optimum dosage of silica fume and lime can be determined according to the discriminant formula.