摘要
为研究上海黏土在固结过程中固结系数、体积压缩系数及渗透系数的变化规律及各向异性,对竖直向和水平向原状上海黏土土样进行逐级加载固结试验。试验结果表明:在固结过程中,固结系数与固结应力关系呈凹型曲线,水平向土样的固结系数略大于竖直向土样,且水平向土样固结系数最小值对应的固结应力小于竖直向土样;在自然沉积过程中,水平向片状结构土颗粒团聚成的絮状物沉淀逐渐形成上海黏土,因而水平向土样的孔隙比比竖直向略大,导致水平向渗透系数比竖直向大,但是由于竖直向与水平向土样在固结过程中受轴力方向与片状结构土颗粒所成角度不同,水平向土样压缩性比竖直向土样小。研究结果不仅完善了上海黏土各向异性的固结力学特性,也可为上海黏土地区的工程施工提供参考。
In order to investigate the anisotropic consolidation characteristics including consolidation coefficients,volume compressibility coefficients and permeability coefficients,the incremental-loading consolidation tests were conducted on vertical and horizontal undisturbed Shanghai clay samples.The test results show that the relationship between consolidation coefficients and consolidation stresses can be represented by concave curves and the consolidation coefficients of the horizontal samples are slightly higher than the vertical ones.In addition,the consolidation stress corresponding to the minimum consolidation coefficient for the horizontal sample is smaller than that of the vertical one.In the natural deposition process,the flake soil particles unite in the horizontal direction into flocculent structure to form Shanghai clay,leading to larger void ratios for the horizontal samples than the vertical ones,and therefore larger horizontal permeability coefficients than the vertical ones.However,the horizontal compressibility is smaller than the vertical one,as the axial force applied is in the different direction from that of the flake soil particles for vertical and horizontal samples respectively.The results not only promote the better understanding of the anisotropic consolidation properties of Shanghai clay,but also provide certain references for engineering construction in Shanghai clay area.
作者
倪静
朱丛薇
韩玉琪
郝港来
NI Jing;ZHU Congwei;HAN Yuqi;HAO Ganglai(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Shenyuan Geotechnical Engineering Co.,Ltd.,Shanghai 200021,China)
出处
《铁道科学与工程学报》
CAS
CSCD
北大核心
2020年第11期2782-2788,共7页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(51608323)。
关键词
上海黏土
固结特性
各向异性
固结系数
压缩系数
渗透系数
Shanghai clay
consolidation characteristics
anisotropy
consolidation coefficient
compressibility
permeability coefficient
