三角洲软土触变特性微观结构演化特征试验研究  

Impact of Thixotropic on Compression Characteristics of Soft Soils in the Delta from Microstructure View

作　　者：赵永峰 余颂[1] 阎晓玲 黄珏皓 ZHAO Yongfeng;YU Song;YAN Xiaoling;HUANG Juehao(China Railway Major Bridge Reconnaissance&Design Institute Co.,Wuhan 430050;School of Civil Engineering and Architecture,Wuhan Polytechnic University,Wuhan,430023;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Wuhan,Hubei 430071;University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]中铁大桥勘测设计院集团有限公司,武汉430050 [2]武汉轻工大学土木工程与建筑学院,武汉430023 [3]中国科学院武汉岩土力学研究所岩石力学与工程国家重点实验室,武汉430071 [4]中国科学院大学,北京100049

出　　处：《土工基础》2025年第1期97-100,共4页Soil Engineering and Foundation

摘　　要：软黏土具有显著的触变现象,研究软土触变影响下的压缩变形特性,对分析软土地基稳定性具有重要意义。通过对珠江三角洲软土原状样和重塑样开展一维压缩试验,并对试验后试样开展电镜扫描试验,从微观结构变化特征的角度分析不同静置时间和含水率条件下软土触变性对其压缩性的影响。试验结果表明:随静置时间增长,重塑样的压缩曲线逐渐向原状样压缩曲线靠近,试样刚度逐渐增加,结构形态逐渐趋向于原状土;试样微观结构孔隙率随静置天数和含水率的增加呈线性增长趋势,当静置天数达到120 d时,重塑样与原状样的微观结构孔隙率基本相等;颗粒定向性随静置时间增长,逐渐以垂直方向排列为主,且分布强度逐渐增大。研究成果可为揭示软土触变性对其压缩特性影响机理提供试验基础。The thixotropic property of the soft clay is more significant.The studying in the compressive characteristics of the soft clay under the influence of thixotropic behavior is of great significance for in-depth analysis of the stability of soft soil foun-dations.The one-dimensional compression tests were conducted on the undisturbed and remolded samples in the Pearl River Delta,then the Scanning Electronic Microscopic(SEM)tests were performed on the samples after the one-dimensional com-pression tests.The influence of the thixotropy on the compressibility of the soft clay under different standing time and moisture content was analyzed from the perspective of microstructure.The experimental results show that as the standing time increa-ses,the compression curve of the remolded sample gradually approaches that of the undisturbed sample,and the stiffness of the sample gradually increases.The structural shape of remolded specimens gradually tends towards the undisturbed specimens;The microstructure porosity of the sample shows a linear increasing trend with the increase of standing days and water content.When the standing days reach 120 days,the microstructure porosity of the reshaped sample is equal to that of the original sam-ple.Besides that,the particle orientation gradually becomes mainly arranged vertically as the standing days increase.And the distribution intensity gradually increases.The above research results can provide experimental basis for revealing the mecha-nism of the influence of thixotropy on compression characteristics in soft clay.

关 键 词：三角洲软土 触变性 一维压缩试验 微观结构 孔隙率 

分 类 号：TU411[建筑科学—岩土工程]