置换率对膨胀土剪切特性影响的试验研究  

Experimental study on effect of displacement rate on shear characteristics of expansive soil

作　　者：史志豪 潘海源 SHI Zhi-hao;PAN Hai-yuan(School of Civil Engineering&Architecture,Anhui University of Science&Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《河南城建学院学报》2022年第2期37-42,共6页Journal of Henan University of Urban Construction

基　　金：高校博士点专项基金资助项目(200803610004)。

摘　　要：利用直剪试验,研究不同置换率膨胀土试样的力学剪切特性,结果表明:随着加砂量的增加,即置换率增加,抗剪强度不断增强,黏聚力线性下降,内摩擦角增加趋势不断增大;中粗砂主要通过改变内摩擦角来提高膨胀土的抗剪强度;黏聚力与置换率的关系可以通过线性方程进行拟合,内摩擦角与置换率的关系可以通过一元二次多项式进行拟合,提出了抗剪强度与置换率、垂直压力的两元回归计算模型。通过静力平衡条件分析,推导出黏聚力、内摩擦角与置换率的关系表达公式,并通过直剪试验得以验证。The shear properties of expansive soil under different displacement rates were studied by direct shear tests.The results show that with the increase of sand content that is the displacement rate.The shear strength increases the cohesion decreases linearly and the internal friction angle increases.The shear strength of expansive soil can be improved by changing the internal friction angle of medium coarse sand.The relationship between cohesion and displacement rate can be fitted by linear equation,and the relationship between internal friction angle and displacement rate can be fitted by a quadratic polynomial.A two-element regression calculation model of shear strength and displacement rate and vertical pressure is proposed.Through the analysis of static equilibrium conditions,the relation formula of cohesion force is derived,the relation formula of internal friction angle is derived,which is verified by the direct shear test.

关 键 词：中粗砂 膨胀土 置换率 抗剪强度指标 

分 类 号：TU411[建筑科学—岩土工程]