土石混合体抗剪强度原位水平推剪试验研究  

Research on Horizontal Push-shear in-situ Test of Shear Strength of Soil-rock Mixtures

作　　者：陈玉留 吴红刚 李慈航 CHEN Yu-liu;WU Hong-gang;LI Ci-hang(Yunnan Gong Dong Expressway Construction Command,Kunming 655200,China;China Northwest Research Institute Co.,Ltd. of CREC,Lanzhou 730000,China;Western Environmental Geotechnical and Site Rehabilitation Technology Engineering Laboratory,Lanzhou 730000,China)

机构地区：[1]云南功东高速公路建设指挥部,昆明655200 [2]中铁西北科学研究院有限公司,兰州730000 [3]西部环境岩土与场地修复技术工程实验室,兰州730000

出　　处：《价值工程》2018年第34期120-125,共6页Value Engineering

基　　金：云南省交通运输厅科技项目(No:201712)

摘　　要：水平挤出法推剪试验是一种在现场进行的原位剪切试验,它比大面积直剪试验更能沿着土的软弱面方向发展,是测定土石混合体强度的一种有效方法。通过对云南省功东高速公路沿线K39~K41工点高边坡地区典型土石混合体试样的现场原位水平推剪试验,采用平均滑动面作为计算滑动面计算得到了该区域土石混合体抗剪指标,有效避免了将土样带回实验室测试对土体造成扰动产生的数据误差。同时,对试样剪切破坏后的破坏面上取样进行了碎石土颗粒粒径分析,分析了土石混合体的尺寸效应对抗剪强度指标的影响,揭示了土石混合体在原位受剪情形下的变形破坏规律。试验表明含石量的不同是影响土石混合体抗剪强度指标的重要因素,含石量较高的土石混合体在水平剪应力达到峰值发生破坏后整体结构尚未丧失,承载力没有明显降低。本次试验为沿线高边坡的稳定性评价提供了有效的参考价值。Horizontal push-shear in-situ test is a kind of in-situ shear test,it can develop along the weak side of soil better than large area direct shear tests,it is an effective method for measuring the strength of soil-rock mixture.The horizontal push-shear in-situ test of typical soil-rock mixture samples in high slope area of K39~K41works along Gong Dong Expressway in Yunnan province was carried out to obtain the shear strength index of soil and rock mixtures,the average sliding surface was used as the calculation of the sliding surface to calculate the shear index of the soil rock mixture in this area,which effectively avoids the data error caused by the soil sample brought back to the soil by the laboratory test.At the same time,the particle size of gravel soil was analyzed by sampling on the failure surface after shear failure to analyze the effect of size effect of soil-rock mixture on shear strength index,and the law of deformation and failure of soil-rock mixture under horizontal push-shear in-situ test is revealed.The test shows that the difference of rock content is an important factor affecting the shear strength of the soil and rock mixtures,after the peak shear stress of the high rock mass,the overall structure has not been lost and the bearing capacity is not obviously reduced.This test provides an effective reference value for the stability evaluation of the high slope along the line.

关 键 词：土石混合体 水平推剪试验 强度指标 平均滑动面 尺寸效应 

分 类 号：TU413[建筑科学—岩土工程]