山区水下填方路堤边坡的稳定性分析

1)杭州交通投资建设管理集团有限公司,浙江杭州 310024; 2)浙江工业大学土木工程学院,浙江杭州 310023; 3)浙江大学建筑工程学院,浙江杭州 310058

岩土工程; 水下填方路堤; 路堤稳定性; 软弱层; 水位变化; 边坡

Slope stability of underwater fill embankment in mountainous area
LÜ Jiang1, ZHAO Hui1, YANG Biao2, ZHAO Jiachen3, and SUN Honglei2

1)Hangzhou Transportation Investment and Construction Management Group Co. Ltd., Hangzhou 310024, Zhejiang Province, P.R.China2)College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, Zhejiang Province, P.R.China3)College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, Zhejiang Province, P.R.China

geotechnical engineering; underwater fill embankment; stability of embankment; weak layer; variation of water level; side slope

DOI: 10.3724/SP.J.1249.2021.02151

备注

山区水下填方路堤在修筑过程中,由于无法对水位以下的原状山体进行清表和修坡处理,填方路堤与原有山体之间会存在软弱层,导致出现边坡稳定性问题. 以千黄高速浙江省大湾区路段工程为背景,采用有限元软件GeoStudio,对水下填方路堤进行数值模拟,分析路堤边坡稳定性受水下填方路堤与原状山体之间的软弱层及水位变化的影响. 研究结果表明,软弱层的厚度、力学参数、相对位置和水位的变化对路堤边坡稳定性有一定影响,路堤边坡的稳定性随着软弱层厚度的增加而减小; 随着软弱层位置的不断上移,路堤边坡的稳定性系数先是下降较快,随后变缓; 当路堤内部存在软弱层时,渗流力对路堤边坡稳定性的影响较为明显.因此,存在软弱层时水位变化对路堤整体稳定性的影响与没有软弱层时有较大差异.

During construction of underwater embankment in mountainous area, there will be a weak layer between the embankment and the original mountain, which leads to the slope stability problem, because it is impossible to clear the surface and repair the slope of the original mountain below the water level. Based on the section of the Qianhuang expressway in the bay area of Zhejiang province, we carry out the numerical simulation of underwater embankment by using the finite element software GeoStudio and analyze the influence of the weak layer between submerged embankment and mountain as well as the variation of water level on the embankment slope stability. The results show that the changes of the thickness, the mechanical parameters, the relative position of the weak layer and the variation of water level have a certain impact on the stability of the embankment slope. With increase of the thickness of weak layer, the stability of the embankment slope decreases. With the continuous upward movement of the position of the weak layer, the stability coefficient of the embankment slope firstly decreases rapidly and then slows down. When there is a weak layer inside the embankment, the seepage force has a more obvious influence on the stability of the embankment slope. And the effect of water level change on the overall stability in the presence of weak layer is significantly different from that in the absence of weak layer.

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