孔隙比对砂类土抗剪强度影响的定量分析  

Quantitative analyses of effect of the shear strength of sandy soil with different void ratios

作　　者：范婷婷 林海[1] 胡小荣[1] FAN TingLing;LIN Hai;HU Xiaorong(School of Cisil Engineering and Architecture,Nanchang University,Nanchang,Jiangxi 330031,China)

机构地区：[1]南昌大学建筑工程学院,江西南昌330031

出　　处：《水文地质工程地质》2018年第6期99-104,共6页Hydrogeology & Engineering Geology

基　　金：江西省博士后科研择优资助项目(2016KY38);国家自然科学基金资助项目(41702324);江西省青年科学基金项目(20161BAB216115);江西省教育厅科学技术研究项目(GJJ150072)

摘　　要：砂类土的密实程度是影响其抗剪强度的重要指标,然而已有研究并没有直观给出砂类土抗剪强度随孔隙比变化的定量规律。控制砂类土的初始孔隙比得到土体所需的抗剪强度,这在土工相似模型试验中具有一定的应用前景。基于砂土的临界状态理论,本文建立了砂类土抗剪强度与孔隙比关系的理论表达式。针对尾矿库现场取回的铜、钨尾砂开展了直剪试验和固结试验,并利用所推导的理论表达式对尾砂在不同状态时的抗剪强度进行了分析。结果表明,随着孔隙比的增加,砂类土的抗剪强度非线性减小,孔隙比越大时抗剪强度减小的幅度越平缓。试验结果证实砂类土抗剪强度与孔隙比关系的理论表达式能够合理描述尾砂在不同孔隙比下的抗剪强度。The compaction degree of sandy soil has a significant influence on the shear strength. However, quantitative analyses of the shear strength of sandy soil with different void ratios have not been given directly in the existing researehes. The target strength value can be obtained by controlling the initial void ratio of sandy soil, which has a certain application prospect in the geotechnical similarity model tests. Based on the critical state theory of sand, theoretical expression of void ratio on the shear strength is established. A series of geotechnical tests are can＇ied out for copper railings and tungsten railings collected from railings pond sites. Using the derived theoretical expression, the shear strength of railings in different states is analyzed. The results show that the shear strength of sandy soil decreases nonlinearly with the increasing void ratio. The shear strength of sandy soil decreases more slowly with the larger void ratio. The experimental resuhs confiml that the theoretical expression of void ratio on the shear strength can reasonably describe the shear strength of railings under different void ratios.

关 键 词：孔隙比 抗剪强度 尾砂 临界状态 直剪试验 

分 类 号：TU411.7[建筑科学—岩土工程]