粒状土与结构接触面强度特性粒径效应影响研究  

Study of the Particle Size Effect on Shear Mechanism of Interface between Granular Soil and Structure

作　　者：成浩 王佳 张家生[3] 黎磊锋 CHENG Hao;WANG Jia;ZHANG Jia-sheng;LI Lei-feng(Foshan Transportation Science and Technology Co.Ltd.,Foshan 528000,China;Foshan Highway and Bridge Engineering Monitoring Station Co.Ltd.,Foshan 528000,China;School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]佛山市交通科技有限公司,佛山市528000 [2]佛山市公路桥梁工程监测站有限公司,佛山市528000 [3]中南大学土木工程学院,长沙市410075

出　　处：《公路》2022年第4期299-305,共7页Highway

基　　金：国家自然科学基金项目,项目编号51978674;湖南省自然科学基金项目,项目编号2017JJ2314;佛山市科技计划项目,项目编号2020001005435。

摘　　要：为研究颗粒粒径对典型粒状土与结构接触面剪切特性的影响,开展了不同粒径范围粗粒土与混凝土接触面大型直剪试验,分析颗粒粒径对接触面剪切强度及接触面强度参数的影响规律,探讨了接触面剪切强度的粒径效应影响机理。结果表明:接触面剪切强度随土体颗粒粒径的增大而明显增大,且当颗粒粒径与结构表面粗糙形貌比值接近1时,其继续增大对接触面剪切强度影响不再明显;不同剪切位移处接触面剪切应力与法向应力均能较好地满足摩尔库伦破坏准则,剪切过程中接触面内摩擦角随剪切位移的增大而增大并逐渐趋于稳定;而不同粒径条件下接触面表观黏聚力随剪切位移的变化规律有着明显的差异;颗粒粒径的增大能显著提高接触面表观黏聚力,对接触面最大内摩擦角无明显影响。To study the effect of particle size on shear strength of interface,a series of large-scale shear tests are performed on interface between concrete and typical granular soils with different particle size.The particle size effect on shear mechanism of interface is discussed based on analysis of evolution law of strength parameters during shear process.The results show that:shear strength of interface increases obviously with the increasing of particle size of granular soil,and the continued increase of particle size has minor effect on shear strength of interface when the ratio of particle size to roughness of structure surface is close to 1.The relationships between normal stress and shear stress at different shear displacement can better satisfy the Mohr-Coulomb failure criterion.During the shearing process,the friction angle of the contact surface increases with the increase of the shear displacement and gradually stabilizes,however,the apparent cohesion of the contact surface varies with the shear displacement under different particle size conditions.The increase of particle size can significantly increase the apparent cohesion of the contact surface,and has no obvious effect on the maximum internal friction angle of the contact surface.

关 键 词：粗粒料 大型直剪试验 接触面 颗粒粒径 强度参数 

分 类 号：TU441[建筑科学—岩土工程]