膨胀土-砂桩界面剪切特性试验研究  

Shear characteristics of expansive soil-sand pile interface

作　　者：谢余军 林斌[1] 范政登 XIE Yu-jun;LIN Bin;FAN Zheng-deng(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》2024年第6期35-40,共6页Journal of Henan University of Urban Construction

基　　金：安徽省自然科学基金项目(2024cx2025)。

摘　　要：为研究土体与弹性材料之间的界面力学特性,通过膨胀土-砂桩接触面直剪试验,对不同含水率和不同垂直压力下剪应力与剪切位移曲线进行分析,探讨含水率对界面抗剪强度的影响。结果表明:在不同的含水率条件下,剪应力与剪切位移的关系曲线均表现为剪切硬化型;随着垂直压力的增加,剪应力峰值增加,其对应的剪切位移变大;界面抗剪强度随含水率增长呈现先增长后降低的变化规律;在同一含水率条件下,界面抗剪强度与垂直压力的关系符合摩尔-库伦准则;界面内摩擦角、界面黏聚力与含水率之间满足二次多项式关系,随着含水率增加,界面黏聚力呈递增趋势,界面内摩擦角则呈下降趋势。To study the mechanical properties of the interface between soil and elastic materials,direct shear tests on the expansive soil-sand pile contact surface were conducted.The shear stress and shear displacement curves under different moisture contents and vertical pressures were analyzed,and the effect of moisture content on the interface shear strength was discussed.The results show that under different moisture content conditions,the relationship curve between shear stress and shear displacement exhibits a shear hardening type;as vertical pressure increases,the peak shear stress increases,and the corresponding shear displacement becomes larger;the interface shear strength first increases and then decreases with an increase in moisture content;under the same moisture content conditions,the relationship between interface shear strength and vertical pressure conforms to the Mohr-Coulomb criterion;the internal friction angle and cohesion of the interface follow a quadratic polynomial relationship with moisture content,where the cohesion of the interface shows an increasing trend with the rising moisture content,while the internal friction angle decreases.

关 键 词：剪切特性 膨胀土-砂桩界面 剪应力-剪切位移关系 含水率 

分 类 号：TU443[建筑科学—岩土工程]