摘要
以四川省雅安市名山区某高速公路灌口组粉砂质泥岩顺层边坡为工程背景,利用现场大型直剪试验地质参数,建立了数值分析模型,以现场施工监测数据验证了模型的准确性,分析了顺层边坡结构面倾角、间距对边坡开挖卸荷及稳定性的影响。结果表明,顺层边坡卸荷区随开挖级数增加而不断扩展,呈现上宽下窄的分布特征,开挖卸荷深度随开挖级数增加迅速减小,深高比随顺层边坡开挖级数增加逐渐减小;顺层边坡安全系数随结构面倾角增大先减小后增大,开挖卸荷导致结构面最不利倾角由20°变化为30°,此时边坡卸荷深度及位移变形量最大;结构面间距对顺层边坡开挖安全系数及稳定性影响较小,但结构面密集边坡的位移变形量远大于结构面稀疏边坡,两者最大水平位移相差近5倍。研究结果可为该地区工程边坡防护设计提供有益的借鉴与参考。
Taking the silty mudstone layered slope of the Guankou Formation of an expressway in Mingshan District, Ya’an City, Sichuan Province as the engineering background, a numerical analysis model is established with the geological parameters of a large-scale direct shear test on site. The accuracy of the model is verified with in-situ construction monitoring data. The influence of the structural surface inclination and spacing of the layered slope on the unloading and stability of the slope is analyzed. The results show that the unloading area of the layered slope continues to expand as the number of excavation levels increases, showing a wide distribution feature at the top and narrow at the bottom. The excavation unloading depth decreases rapidly with the excavation, and the depth-to-height ratio gradually decreases with the increase of the excavation height of the layered slope.The safety factor of the layered slope first decreases and then increases with the increase of the structural surface inclination. Excavation unloading causes the most unfavorable inclination angle of the structural surface to change from 20°to 30°. When the slope angle of the structural surface is 30°, the unloading depth and displacement deformation are the largest. The distance between structural surface has minor impact on the safety factor and stability of layered slope excavation, but the displacement and deformation of dense structural surface slope is much greater than that of sparse structural surface slope, and the maximum horizontal displacement difference between the two is nearly 5 times. The research results can provide useful reference for the design of project slope protection in this area.
作者
何云勇
李蜀南
向波
马建林
HE Yun-yong;LI Shu-nan;XIANG Bo;MA Jian-lin(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Sichuan Highway Planning,Survey,Design and Research Institute Ltd,Chengdu 610000,China;Transportation and Municipal Engineering Institute,Power China Huadong Engineering Corporation Limited,Hangzhou 311122,China)
出处
《公路》
北大核心
2022年第6期1-7,共7页
Highway
基金
国家重点研发计划项目,项目编号2016YFC0802203
四川省交通运输科技项目,项目编号2016B2-2。
关键词
道路工程
红层泥岩
顺层边坡
结构面
开挖卸荷
稳定性
road engineering
red mudstone
layered slope
structural surface
excavation unloading
stability