摘要
南水北调中线一期工程总干渠膨胀岩(土)试验段工程潞王坟段的渠坡处理方式之一是换填黏性土料处理措施,通过开展物理性试验、击实试验、膨胀特性试验和原位测试等来了解换填黏性土料的工程特性。研究表明:(1)换填黏性土料颗粒组成差异较大,以砂粒和粉粒为主,其次为砾,黏粒和胶粒成分较少,其级配一般;(2)轻型击实条件下,换填黏性土料最优含水率为17.7%,对应的最大干密度为1.71g/cm3;重型击实条件下,换填黏性土料最优含水率为18.4%,对应的最大干密度为1.87g/cm3;(3)换填黏性土料的相对密度为2.7,液限在37.6%～38.7%之间,塑限在17.1%～19.2%之间,塑性指数在19.4～21.2之间,属于低液限黏土;(4)当取样深度在0.0～3.5m之间时,换填黏性土料的自由膨胀率在40.0%之内,无膨胀潜势;当取样深度在3.5～4.5m之间时,换填黏性土料的自由膨胀率在42.0%～76.0%之内,具有中弱膨胀潜势;(5)换填黏性土料的旁压模量Em、侧胀模量ED随深度变化不明显,当含水率变化时有部分成果有随含水率增加而模量参数降低趋势。该成果为换填黏性土料在南水北调中线一期工程总干渠膨胀岩(土)试验段工程中的应用提供了科学依据。
One of the slope treatment measures is the replaced-backfilling clay treatment in the Luwangfen test region of middle-route of South-to-North water division project.The engineering property of replaced-backfilling clay is studied by physical test,compaction test,expansive property test and in-situ test.Studies show that:(1)the diversity of particle component of it is obvious,in which sand grain and silt are dominant,gravel is lesser,cosmid and colloidal particle are least;(2)the optimal water content of replaced-backfilling clay is 17.7% with the corresponding maximum density of 1.71 g/cm3 under the condition of light compaction,the optimal water content is 18.4% with the corresponding maximum density of 1.87g/cm3 under the condition of heavy compaction;(3)the specific gravity of replaced-backfilling clay is 2.7,liquid limit is between 37.6%-38.7%,plastic limit is between 17.1%-19.2%,plasticity index is between19.4-21.2,therefore,it belongs to low liquid limit clay;(4)when the sample of replaced-backfilling clay is selected within the depth of 3.5 m,the free expansive rate is within 40.0%,which means there is no expansive potential;when the sample is selected between the depth of 3.5-4.5 m,the free expansive rate is between 42.0%-76.0%,which means there is middle or weak expansive potential;(5)there is no obvious relation between Em(ED) of replaced-backfilling clay and depth,but the module parameters of it has the decreasing tendency with the increase of water content.The result provide scientific reference for the application of replaced-backfilling clay to the middle-route of South-to-North water division project.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2009年第S2期154-157,共4页
Rock and Soil Mechanics
基金
国家"十一五"科技支撑计划"膨胀土地段渠道破坏机制及处理技术研究"课题(No.2006BAB04A10)
长江科学院博士科研启动金:利用旁压模量判别膨胀岩膨胀等级的试验研究(No.YJJ0809)
关键词
南水北调
换填黏性土料
工程特性
South-to-North water diversion
replaced-backfilling clay
engineering property
