粗颗粒土三轴试样橡皮膜嵌入量试验研究  

Experimental study on embedding amount of rubber film of triaxial specimens of coarse-grained soil

作　　者：朱俊高[1] 朱材峰 王思睿 ZHU Jun-gao;ZHU Cai-feng;WANG Si-rui(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing 210024,China;Zhenjiang Electric Power Design Institute,Zhengjiang 212000,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210024 [2]镇江电力设计院,江苏镇江212000

出　　处：《岩土工程学报》2022年第12期2160-2166,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金委员会雅砻江联合基金项目(U1865104);长江水科学研究联合基金重点支持项目(U2040221);河海大学大型仪器设备共享基金项目(GX202205B,GX202204B);华能集团总部科技项目。

摘　　要：粗颗粒土三轴排水剪试验过程中,尤其是在等向压缩和等应力比等加载条件下,橡皮膜嵌入颗粒间隙影响试样体积变形测量的准确性。针对此问题,使用刚性壁的新型静止侧压力系数试验仪及柔性壁的常规三轴试验仪对双江口土石坝的坝壳粗粒料进行了K0固结试验,研究了有效净压力p、初始孔隙比e0及平均粒径d50对单位面积橡皮膜嵌入量的影响,提出一种可以较精确测量橡皮膜嵌入量的新方法。试验结果表明:单位面积橡皮膜嵌入量与有效净压力p/pa呈较好的双曲线型关系;有效净压力p、初始孔隙比e0及平均粒径d50对橡皮膜嵌入量均有较大影响。基于试验结果,提出了一个可预测粗颗粒土三轴试验时单位面积橡皮膜嵌入量的经验公式,并进行了验证。与前人试验结果对比表明,经验公式可较好预测粗颗粒土三轴试验中的橡皮膜嵌入量。During the triaxial drainage shear tests on coarse-grained soil,the rubber film embedded in the particle gap affects the accuracy of measuring the volume deformation of specimens,especially under loading conditions such as isotropic compression and equal stress ratio.In response to this problem,the K0 consolidation tests are carried out on the coarse-grained shell material of the Shuangjiangkou earth-rock dam using the new static lateral pressure coefficient tester for rigid walls and the conventional triaxial tester for flexible walls.The effects of the effective net pressure p,the initial void ratio e0 and the average particle size d50 on the amount of rubber film embedded per unit area are studied.A new method can be used to accurately measure the embedding amount of rubber film.The test results show that the embedding amount of rubber film per unit area has a good hyperbolic relationship with the effective net pressure p/pa,and the effective net pressure p,the initial void ratio e0 and the average particle size d50 all have a greater impact on the embedding amount of rubber film.Based on the test results,an empirical formula for predicting the amount of rubber film embedded per unit area in the triaxial tests on coarse-grained soil is proposed and verified.Compared with the previous test results,the proposed empirical formula can better predict the amount of rubber film embedded in the triaxial tests on coarse-grained soil.

关 键 词：粗颗粒土 K0试验 橡皮膜 嵌入量 有效净压力 

分 类 号：TU411[建筑科学—岩土工程]