围压对砂砾石地基管涌影响的试验研究  

Experimental Investigation of the Influence of Confining Pressure on Piping in Sandy Gravel Foundation

作　　者：杨加智[1] 刘星星[2] 盛金昌[2] 

机构地区：[1]中国电建集团华东勘测设计研究院有限公司,浙江杭州310014 [2]河海大学水利水电学院,江苏南京210098

出　　处：《华北水利水电大学学报（自然科学版）》2014年第5期16-19,共4页Journal of North China University of Water Resources and Electric Power：Natural Science Edition

基　　金：国家自然科学基金项目(51009053)

摘　　要：砂砾石地基所处的实际应力状态对其管涌发生、发展过程的影响明显.为了研究有围压状态下砂砾石地基的管涌现象,利用渗流-侵蚀-应力耦合试验装置,开展了不同围压状态下缺乏中间级配的管涌型砂砾石料的耦合试验研究,建立了管涌临界渗透坡降与围压之间的线性经验公式,表明管涌临界坡降随着围压的增大而增大;通过对管涌发生、发展过程中的土样渗透性及细颗粒流失情况的分析,发现围压越大,土体渗透系数及其变幅越小,对管涌发展的遏制效果越明显.The actual stress states of sandy gravel foundation play a significant role in the generation and evolution of piping. In order to study the phenomenon of the piping-typed sandy gravel foundation under confining pressure, a series of experiments on the pipingtyped sandy gravel foundation lack of intermediate grading particle size under different confining pressure were carried out using experimental apparatus of seepage-erosion-stress coupling. A linear empirical formula on the critical hydraulic gradient of seepage piping denoted by the confining pressure was established based on the experiment results, which showed that the critical hydraulic gradient increased with the increase of the confining pressure. Soil samples＇ permeability and fine particle loss during the generation and evolution of piping were also analyzed, which showed that the bigger the confining pressure was, the smaller the soil samples＇ permeability coefficient and its fluctuation became, and the more obvious the restraint effect on the piping development was.

关 键 词：砂砾石 管涌 围压 渗流-侵蚀-应力耦合 

分 类 号：TV16[水利工程]