法向循环荷载下土石混合料-织物界面剪切特性研究  

Analysis of shear characteristics of soil-rock mixture-geotextile interface under normal cyclic loading

作　　者：李水江 姚嘉敏 刘飞禹[2] 刘洪波 侯娟[2] LI Shui-jiang;YAO Jia-min;LIU Fei-yu;LIU Hong-bo;HOU Juan(Guangzhou Environmental Protection Investment Group Co.,Ltd.,Guangzhou,Guangdong 510330,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)

机构地区：[1]广州环保投资集团有限公司,广东广州510330 [2]上海大学力学与工程科学学院,上海200444

出　　处：《岩土力学》2023年第11期3082-3090,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.52078285)。

摘　　要：筋-土界面动力剪切特性会影响加筋土石混合料路基的稳定性和耐久性。采用室内大型动态直剪仪,对5种含石量(0%、25%、50%、75%和100%)下的土石混合料-土工织物界面进行了一系列静、动力直剪试验,分析了法向应力振幅(10、20、30、40、60 kPa)和法向加载频率(0.5、1.0、2.0 Hz)对界面剪切响应的影响规律,并在试验的基础上建立了界面摩擦系数的经验公式。结果表明:界面上、下界抗剪强度随含石量的增大表现为先增大后减小的趋势,并与法向应力振幅呈正相关关系,与法向加载频率呈负相关关系;增大含石量会使界面剪胀效应增大,增大振幅和频率会使其减小;含石量和振幅的增大会导致界面摩擦效应增强;在试验的基础上建立了与含石量、振幅、频率相关的界面摩擦系数经验公式,与试验结果吻合较好。The dynamic shear characteristics of the reinforcement-soil interface affect the stability and durability of reinforced soil-rock mixture subgrades.A series of static and dynamic direct shear tests was conducted on the soil-rock mixture-geotextile interface using a large dynamic direct shear apparatus under different rock contents(0%,25%,50%,75% and 100%).The effects of normal stress amplitude(10,20,30,40 and 60 kPa)and normal loading frequency(0.5,1.0 and 2.0 Hz)on the shear response of the interface were analyzed.The test results indicate that the shear strength of the upper and lower boundaries of the interface first increases and then decreases with the increase in rock content.This is positively correlated with the normal stress amplitude,while negatively correlated with the normal loading frequency.An increase in rock content amplifies the interface dilatancy effect,while increases in stress amplitude and loading frequency reduce the interface dilatancy effect.The enhancement of the interface friction effect can be attributed to increased rock content and stress amplitude.An empirical formula for the interface friction coefficient,as a function of rock content,stress amplitude,and loading frequency,has been established.This formula coincides well with the test results.

关 键 词：筋土界面 土石混合料 循环荷载 含石量 应力振幅 加载频率 

分 类 号：TU416.2[建筑科学—岩土工程]