组装式变尺寸直剪仪的研制  

Development of assembled variable dimension direct shear apparatus

作　　者：薛晨[1,2,3] 符文熹[1,2] 何思明 XUE Chen;FU Wen-xi;HE Si-ming(State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu,Sichuan 610065,China;College of Water Resource ＆ Hydropower,Sichuan University,Chengdu,Sichuan 610065,China;China Railway First Survey Design Institute Group Ltd.,Xi＇an,Shaanxi 710043,China;Key Laboratory of Mountain Hazards and Earth Surface Process,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu,Sichuan 610041,China)

机构地区：[1]四川大学水力学与山区河流保护国家重点实验室,四川成都610065 [2]四川大学水利水电学院,四川成都610065 [3]中铁第一勘察设计院集团有限公司,陕西西安710043 [4]中国科学院成都山地灾害与环境研究所山地灾害与地表过程重点实验室,四川成都610041

出　　处：《岩土力学》2018年第10期3907-3914,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.41472325);四川省国际合作项目(No.2018HH0082);国家重点基础研究发展规划项目(973计划)(No.2015CB057903)~~

摘　　要：由于粗粒土的直剪试验存在显著的尺寸效应,且室内常规直剪仪无法调整试样尺寸,所以难以准确获得粗粒土的抗剪强度参数。基于此问题,介绍了一种可以改变试样尺寸的组装式直剪仪。该直剪仪由出力装置、位移量测装置、反力框架、剪切盒等部分组成。通过改变每一层剪切盒的钢环嵌套个数来改变试样的直径,直径有6.18、10、15、20 cm 4个取值;改变剪切盒的叠置层数来改变试样的高度,高度有5、10、15、20 cm 4个取值,试样直径和高度共有16种组合。在此基础上,选取薛城水电站引水隧洞开挖弃渣为试样,进行5组平行直剪试验,验证了该直剪仪的可重复性以及试验结果的可靠性。改变试样直径D与高度H的组合,进行一系列直剪试验研究了该试样直剪试验的尺寸效应,得出该试样的合理试样尺寸。Due to the significant size effect in the direct shear test of coarse grained soil, and the incapability of the general indoor direct shear apparatus to adjust the size of the sample, it is difficult to obtain the shear strength parameters of coarse grained soil. Therefore, an assembled direct shear apparatus which can be employed to change the size of the sample is introduced. This direct shear apparatus is composed of an output device, a displacement measuring device, a reaction frame, and a shear box. By changing the number of steel rings nested in each shear box, the diameter of the sample can be set to be 6.18, 10, 15 and 20 cm. By changing layers of shear boxes, the height of the sample can be set to be 5, 10, 15 and 20 cm. The values of diameter and height of the sample can form 16 combinations in total. On this basis, abandoned slags from the diversion tunnel of Xuecheng Hydropower Station were selected as samples, and then 5 groups of parallel direct shear tests were carried out to verify repeatability of the direct shear apparatus and reliability of the test results. By changing the diameter D and height H, a series of direct shear tests was conducted to study the size effect of the sample, and to determine the reasonable size of the sample.

关 键 词：粗粒土 尺寸效应 改进直剪仪 

分 类 号：TU415[建筑科学—岩土工程]