土石混合体大型直剪设备研发与应变锁骨强度特征试验研究  

DEVELOPMENT ON LARGE DIRECT SHEAR EQUIPMENT FOR SOIL-ROCK MIXTURE AND EXPERIMENTAL STUDY ON STRENGTH CHARACTERISTICS OF STRAIN LOCKING

作　　者：李志清[1,2,3] 文吉英 姚国明 周应新 胡瑞林 胡峰[1] LI Zhiqing;WEN Jiying;YAO Guoming;ZHOU Yingxin;HU Ruilin;HU Feng(Key Laboratory of Shale Gas and Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China;Institutions of Earth Science,Chinese Academy of Sciences,Beijing 100029,China;Zhongnan Yekan Resources and Environment Engineering Co.,Ltd.,Wuhan 430035,China;Beijing Zhongyan Tiandi Technology Co.,Ltd.,Beijing 101513,China;Baoshan Longying Expressway Co.,Ltd.,Baoshan 678000,China;Yunnan Communications Investment&Construction Group Co.,Ltd.,Kunming 650100,China)

机构地区：[1]中国科学院地质与地球物理研究所,中国科学院页岩气与地质工程重点实验室,北京100029 [2]中国科学院大学,北京100049 [3]中国科学院地球科学研究院,北京100029 [4]中南冶勘资源环境工程有限公司,武汉430035 [5]北京中岩天地科技有限公司,北京101513 [6]保山隆营高速公路有限公司,保山678000 [7]云南省交通投资建设集团有限公司,昆明650100

出　　处：《工程地质学报》2023年第6期1975-1988,共14页Journal of Engineering Geology

基　　金：第2次青藏高原综合科学考察研究项目(资助号:2019QZKK0904);国家自然科学基金面上项目(资助号:42177146);国家重点研发计划项目(资助号:2019YFC1509903);云南省重点研发计划项目(资助号:202103AA080013)。

摘　　要：土石混合体是一种介于均质土体和碎裂岩体之间的特殊工程地质材料,在我国分布广泛。本文总结了国内外现有的主要大型直剪仪的设计参数与功能优势,在克服传统直剪试验中存在的正应力不恒定、垂直荷载偏心、剪切破坏面固定及液压系统不稳定等缺陷基础上,研发了基于多尺度、蠕变、冻融与渗流多物理场控制条件下的SRM-1000型电机伺服控制大型土工抗剪强度实验设备,实现了直剪试验、斜剪试验、叠剪试验、冻融循环试验等功能。分别采用不同含石量(0、30%、50%、70%)、不同颗粒尺寸(L1、L2、L3、L4)试样,在不同垂直压力(50 kPa、200 kPa、300 kPa、400 kPa)条件下开展了直剪变形与强度特性测试。采用铝丝监测了剪切带内块石间的力链结构特性,研究了块石压密、滑移、错动导致剪缩或剪胀的变化规律,揭示了不同条件下土石混合体的应变硬化与应变锁固强度特征。As a special engineering geological material between homogeneous soil mass and cataclastic rock mass,soil and rock mixture(SRM)is widely distributed in China.This paper summarizes the design parameters and functional advantages of the main large direct shear apparatus at home and abroad.It researches the SRM-1000 type large geotechnical shear strength experiment equipment with motor servo control.It realizes the direct shear test,the oblique shear test and shear test,freeze-thaw cycling test,based on multi-scale,creep,freezing-thawing and seepage control conditions of more physical field.The new apparatus solves the problems including that the normal stress is not constant,the vertical load cannot be aligned to the sample center,the shear failure surface is unique and fixed,and the hydraulic system is unstable.Samples with different stone contents(0,30%,50%,70%)and particle sizes(L1,L2,L3,L4)are used to test the direct shear deformation and strength characteristics under different vertical pressures(50kPa,200kPa,300kPa,400kPa).The structural characteristics of force chain between block stones in shear zone are monitored by aluminum wires.The variation rules of bulk shrinkage and expansion caused by compaction,slip and dislocation of block stones are studied.The characteristics of strain hardening and strain locking strength of SRM under different conditions are revealed.

关 键 词：土石混合体 直剪仪 粗粒土 碎石土 应变锁固 

分 类 号：P642.3[天文地球—工程地质学]