公路改扩建工程高边坡开挖稳定性分析  

Stability Analysis of High Slope Excavation in Highway Reconstruction and Expansion Projects

作　　者：邹俊 ZOU Jun(Hubei Xiantao Sida Highway Construction Co.,Ltd.,Xiantao,Hubei 433000,China)

机构地区：[1]湖北省仙桃市四达公路建设有限公司,湖北仙桃433000

出　　处：《黑龙江交通科技》2024年第11期54-58,共5页Communications Science and Technology Heilongjiang

摘　　要：为了保证公路改扩建高边坡在开挖期间不出现安全事故,分析高边坡的失稳成因和失稳过程,以G105线改扩建项目的K1155+380断面高边坡为分析对象,将两种开挖方案进行对比。随后,基于规范选取了高边坡开挖安全系数,基于简化毕肖普法计算了未支护高边坡在不同开挖工况下的安全系数。当开挖至最后一级边坡后,高边坡安全系数降低至1.1以下,稳定性较差,需及时支护。最后,从锚索的锚固角、锚固力、布置间距、张拉程序等方面阐述了高边坡的支护方案设计要点,计算了高边坡在分级开挖、分级支护工况下的安全系数,并利用监测桩监测各级边坡坡脚的水平位移,分析成果表明开挖会降低边坡安全系数、支护会增大边坡安全系数,且1#~4#监测桩的水平位移均在2.0 cm以下,满足设计要求。In order to ensure that there are no safety accidents during the excavation of high slopes for highway reconstruction and expansion,the causes and processes of instability of high slopes are analyzed.The K1155+380 section high slope of the G105 line reconstruction and expansion project is taken as the research object,and two excavation schemes are compared.Subsequently,based on the Code,the safety factor for high slope excavation was selected,and the safety factor for unsupported high slopes under different excavation conditions was calculated using the simplified Bishop method.After excavating to the last level of slope,the safety factor of the high slope decreases to below 1.1,indicating poor stability and requiring timely support.Finally,the key points of the support scheme design for high slopes were elaborated from the aspects of anchor angle,anchoring force,arrangement spacing,and tensioning program.The safety factor of high slopes under graded excavation and graded support conditions was calculated,and the horizontal displacement of the slope foot at each level was monitored using monitoring piles.The research results showed that excavation would reduce the slope safety factor,while support would increase it.Moreover,the horizontal displacement of monitoring piles 1#to 4#was all below 2.0 cm,meeting the design requirements.

关 键 词：公路改扩建 高边坡 开挖顺序 安全系数 支护方案 

分 类 号：U416.14[交通运输工程—道路与铁道工程]