珠三角西部软土变形特性试验研究  

An Experimental Study of Deformation Characteristics of Soft Soil in the Western Pearl River Delta

作　　者：何程铃 刘红军[1] HE Cheng-ling;LIU Hong-jun(School of Civil Engineering and Architecture,Wuyi University,Jiangmen 529020,China)

机构地区：[1]五邑大学土木与建筑学院

出　　处：《五邑大学学报（自然科学版）》2019年第4期29-34,共6页Journal of Wuyi University(Natural Science Edition)

摘　　要：珠江三角洲西部地区广泛分布第四系全新统海陆交互相沉积软土,为了研究该区域软土的变形特性,取5.20~5.40 m、 8.20~8.40 m、 11.40~11.60 m共3个深度的土样,对每一深度的土样进行了竖向和横向的一维固结压缩试验,重点研究了土样的压缩量、孔隙比、压缩系数及压缩模量随固结压力及压缩时间的变化情况,同时考虑了取样深度和软土各向异性的影响.研究结果表明:固结压缩时间在前240 min时,土样的压缩量均明显增大,随后压缩量的增大幅度逐渐变缓,并趋于稳定状态,说明土样的主固结状态已基本完成;软土的孔隙比均随固结压力的增大而减小,当固结压力在200 kPa以内,孔隙比变化较大,取样深度对孔隙比减小的范围影响不大;在固结压力小于100 kPa时,压缩系数随固结压力的增加而显著减少,当固结压力大于100 kPa时,竖向和横向得到的压缩系数几乎相同;压缩模量随固结压力的增加接近于直线增长,随着固结压力的增加,埋深浅的软土压缩模量增加较快.论文的研究成果可为本区域软土地基工程提供合理可靠的设计依据.The Quaternary Holocene intercontinental sedimentary soft soil is widely distributed in the western part of the Pearl River Delta, In order to study the deformation characteristics of soft soil in this area, soil samples of the three depths of 5.20-5.40 m, 8.20-8.40 m and 11.40-11.60 m were taken, and the soil samples of each depth were subjected to vertical and lateral one-dimensional consolidation compression test. The research focused on the compressive amount, void ratio, compr essibility coefficient and compressive modulus of the soil samples varying with the consolidation pressure and compression time. The effects of sampling depth and soft soil anisotropy were also considered. The results show that when the consolidation compression time is 240 min, the compressive amount of the soil sample increases obviously, and then the increase of the compression amount gradually becomes slower and tends to be stable, indicating that the main consolidation state of the soil sample has been basically completed. The pore ratio of soft soil decreases with the increase of consolidation pressure, when the consolidation pressure is within 200 kPa, the void ratio changes greatly, and the sampling depth has little effect on the range of pore ratio reduction. When the consolidation pressure is less than 100 kPa, the compression coefficient decreases significantly with the increase of the consolidation pressure. When the consolidation pressure is greater than 100 kPa, the compression coefficients obta ined in the vertical and lateral directions are almost the same. The compressive modulus increases linearly with the increase of consolidation pressure. As the consolidation pressure increases, the compressive modulus of the soft soil in shallow depths inc reases rapidly. The research results of the paper provide the basis for the engineering design of soft soil foundation in the region.

关 键 词：珠三角西部软土 取样深度 压缩系数 压缩模量 

分 类 号：U416.1[交通运输工程—道路与铁道工程]