等加载速率下软土固结特性试验研究  

Research on consolidation test of soft clay under constant loading rate

作　　者：周文渊[1] 闪黎[2] 宋新江[1] 徐海波[1] 

机构地区：[1]安徽省.水利部淮河水利委员会水利科学研究院,安徽蚌埠233000 [2]淮河水利委员会治淮工程建设管理局,安徽蚌埠233000

出　　处：《南水北调与水利科技》2015年第4期695-698,712,共5页South-to-North Water Transfers and Water Science & Technology

基　　金：水利部科技推广计划项目(TG1414);水利部科技推广计划项目(1408085ME99);2015年安徽省省属社会公益类科研机构专项资金项目

摘　　要：等加载速率固结试验是在控制固结应力的施加速率为一常数条件下研究土体固结特性的试验方法。采用GDS高级固结仪,开展了四种加载速率与瞬时加载的软土固结试验研究,分析了土样的固结变形特性与孔隙水压力变化规律。试验与分析结果表明,加载速率越大土样固结速率越快,土样完成固结所需的时间越短;土体的最终变形量由固结应力大小决定,与加载速率无关;随着固结应力施加速率的增加,加载完成时土样的平均固结度呈下降趋势;加载速率越大,土样底部的孔隙水压力上升速率越快,孔隙水压力极值越大;孔隙水压力在固结应力加载完成前达到极值,随后呈下降趋势,有效应力迅速增加。Consolidat ion test under constant loading rate is the test method for the consolidation process of clayey soil w ith a con-stant rate of control consolidation stress. Consolidat ion t ests with four different loading rates and instantaneous loading were carried out using the GDS advanced consolidat ion testing system. The consolidation deformation characteristics of soft clay and the change law of pore-w ater pressure were analyzed. The findings indicated that ( 1) the faster of loading rate, the larger de-formation rate and the shorter time for consolidation of soil sample; ( 2) the final deformation of soil sample is independent of the loading rate but dependent on the magnit ude of consolidation stress; ( 3) with the increasing of loading rate of consolidation st ress, the average consolidation degree of soil sample decreases after loading; ( 4) t he higher the loading rate, t he faster the in-creasing rate of pore pressure in the soil sample bottom and the larger t he ext reme value of pore pressure; and( 5) the pore pres-sure reaches the maximum before the completion of loading of consolidation stress, then decreases w hile the effect ive stress in-creases rapidly.

关 键 词：等加载速率固结 GDS高级固结仪 孔隙水压力 固结变形 固结度 最终变形量 软土 

分 类 号：TU447[建筑科学—岩土工程]