扰动土-结构接触面抗剪强度特性试验研究  

Experimental Research of Shear Strength Characteristics on Disturbed Soil-structure Interfaces

作　　者：赵少飞 戴志广 刘鑫 刘欣怡 

机构地区：[1]华北科技学院建筑工程学院,北京101601

出　　处：《地下空间与工程学报》2018年第1期67-71,228,共6页Chinese Journal of Underground Space and Engineering

基　　金：中央高校基本科研业务费(3142014019;3142015049)

摘　　要：针对地下空间开发等原因引起的扰动土-结构接触面抗剪强度特性,制备了干密度、孔隙比、含水率和饱和度4类物理性质指标变化的扰动土样,在传统应变控制直剪仪上通过改进的试验方案,探究扰动土与粗糙、光滑和极光滑3类粗糙度接触面的抗剪强度变化规律。试验结果表明,对各类粗糙度接触面,抗剪强度及外摩擦角,均随含水率、孔隙比、饱和度的增大而非线性减小,而随干密度的增加而非线性增加,其中含水率在10%~15%或饱和度在40%~50%范围时改变显著。对于极光滑接触面,抗剪强度及外摩擦角受土的扰动影响微小,基本可以忽略。试验结果为扰动土-结构接触面抗剪强度规律和扰动土-结构相互作用的进一步研究提供了试验依据。Disturbed soil samples are prepared for simulating physical property variation in dry density,water content,void ratio and degree of saturation caused by construction of underground building. An improved experimental process is presented to study shear strength characteristics on disturbed soil-structure interfaces using a conventional strain-controlled direct shear instrument. Three types of interface roughness are employed which are rough,smooth and extremely smooth to reflect actual surfaces of concrete and steel building materials. Experimental results show that for any types of interface roughness,shear strength,indicating the angles of external frication of disturbed soilstructure interfaces,overall nonlinearly decreases with increases of soil water content,void ratio or degree of saturation,but nonlinearly increases with increase of its dry density. In particular,the shear strength and the angles of external frication vary rapidly for a slight change of water content within the range between 10% and 15% or of degree of saturation within the range between 40% and 50%. However they vary gently with water content or degree of saturation out of the two ranges. For the extremely smooth interface variation of the shear strength may be ignored caused by the changes of disturbed soil property. Experimental results would be fundamental for investigation of the rules of shear strength on disturbed soil-structure interfaces and the disturbed soil-structure interaction.

关 键 词：扰动土 土-结构接触面 抗剪强度 粗糙度 

分 类 号：TU411[建筑科学—岩土工程]