摘要
杭州湾沿岸广泛分布的软黏土是一种不良地质土,其强度低、压缩性高,物理特性受水文、含盐量等因素影响大。孔隙水含盐量在不同的季节下受河流、潮汐、降雨等因素的影响会发生波动,这就使得软黏土的物理特性发生较大的变化。对杭州湾沿岸软黏土孔隙水含盐量测定表明冬季含盐量高,夏季含盐量低。通过直剪试验与侧限压缩试验,得到了不同孔隙水含盐量对土体物理特性的影响规律;根据试验结果并结合现场孔隙水监测资料,对软黏土全年物理变化特性进行预测,以弥补现场勘察结果所带来的不足,从而提高工程建设的安全性。结果表明土体孔隙水含盐量在5%以内时,孔隙水含盐量越高,土体的内摩擦角与黏聚力越低,土体压缩性越强。杭州湾沿岸地区冬季土体的力学性能较差,应该更加注重冬季工程地质灾害的防治。
The soft clay widely distributed along the coast of Hangzhou Bay is an unfavorable soil with low strength,high compressibility,and the physical properties are greatly affected by factors such as hydrology and salt content.The salt content of pore water fluctuates under the influence of river,tide,rainfall and other factors in different seasons,which makes the physical properties of soft clay change greatly.The determination of the salt content of the soft clay pores along the Hangzhou Bay shows that the soft clay has high salt content in winter and low salt content in summer.Through the direct shear test and the lateral compression test,the influence of different salt content of pore water on the physical properties of soft clay was obtained.Based on test results and on-site pore water monitoring data,the whole year physical properties of soft clay are predicted,so as to make up the shortcomings in the site investigation and improve the construction safety of the project.The results show that when the salt content of soil pore water is within 5%,the internal friction angle and cohesion of the soil is lower,and the soil compressibility is stronger if the salt content of pore water is higher.The mechanical properties of the soil along the Hangzhou Bay coast are poor in winter,and more attention should be paid to the prevention of engineering geological disasters in winter.
作者
周洁
李泽垚
万鹏
Zhou Jie;Li Zeyao;Wan Peng(College of Civil Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Geotechnical and Underground Engineering,Ministry of Education,Shanghai 200092,China;Survey and Investigation Branch,East China Electric Power Design Institute Co.,Ltd.of China Power Engineering Construction Group,Shanghai 200092,China)
出处
《工程勘察》
2020年第12期1-6,共6页
Geotechnical Investigation & Surveying
基金
国家自然科学基金青年基金项目(41702299)
关键词
软黏土
含盐量
压缩特性
抗剪特性
岩土工程勘察
soft clay
salt content
compression characteristics
shear properties
geotechnical investigation
