充填土沉积特性试验研究  

Laboratory Study on Sedimentation Behavior of Dredged Fills

作　　者：王年香[1] 何宁[1] 章为民[1] 顾行文[1] 任国峰[1] 

机构地区：[1]南京水利科学研究院,江苏南京210024

出　　处：《水利与建筑工程学报》2015年第2期90-94,196,共6页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金项目(51179106);国家高技术研究发展计划863项目(2012AA112509);江苏省交通科学支撑计划项目(BE2011718)

摘　　要：疏浚土及吹填泥能否作为充填料是土工织物充填袋筑堤技术关键问题。针对连云港疏浚土,开展泥水混合物沉积模拟试验,研究了黏粒含量和初始含水率对泥水混合物自重沉积特性的影响,以及作为充填材料的适用性。试验结果表明:充填土沉积过程可分为沉淀阶段和自重固结阶段。沉淀阶段时间较短,土性指标很快趋于稳定。自重固结阶段土性指标几乎没有变化,表明充填土自重固结是相当缓慢的;充填土初始含水率越大,或黏粒含量越小,最大沉淀速率越大,沉淀越快。初始含水率越大,或黏粒含量越大,沉淀结束时充填土含水率和孔隙比越大,密度越小;当充填土黏粒含量大于10%时,在确保充填土的流动性和可灌性前提下,应尽量减小初始含水率,从而降低充填土沉淀结束时的含水率和孔隙比,提高密度;当充填土料的黏粒含量大于30%时,最大沉淀速率很小,沉淀的持续时间将会比较长,不利于工程施工。因此,充填土料的黏粒含量应小于30%。Whether the dredged fill can be used as filling material of the geotextile bags is a key technical problem in the construction of dams and embankments. Laboratory tests were carried out to study the influence of clay content and initial water content on the self-weight sedimentation behavior and the applicability as filling material of dredged fills in Lianyungang Harbor. Results indicate that the sedimentation process can be divided into sedimentation stage and self-weight consolidation stage. The former stage is very short,and the soil indexes stabilize quickly.The latter stage takes very long time,and the soil indexes rarely change. The maximum sedimentation rate is larger and sedimentation time is shorter with larger initial water content or smaller clay content. The larger the initial water content or the clay content is,the larger the final water content and void ratio of dredged fill is,and the smaller the final density is after sedimentation. If clay content is larger than 10%,the initial water content should be as small as possible with liquidity of filling,so as to get smaller final water content,void ratio and larger final density. If clay content is larger than 30%,the maximum sedimentation rate is very small and the duration of sedimentation is relatively long,which is disadvantageous to the engineering construction. Therefore,the clay content of dredged fill should be less than 30%.

关 键 词：充填土 沉积特性 黏粒含量 初始含水率 试验研究 

分 类 号：TU44[建筑科学—岩土工程]