开挖方式对二元结构边坡稳定性影响分析

Influence of Excavation Sequences on the Stability of Soil-Rock Dual Structure Formations

以江西省景德镇某地区基坑开挖为案例,定量分析了四种不同的开挖方式对二元结构边坡稳定性的影响。通过建立基坑开挖模型,模拟了一步开挖、分步开挖、整体跳挖和分步跳挖四种开挖方式,在对基坑斜面不同部位实时监测的基础上,定量分析得出基坑开挖导致应力重分布,在基坑斜面底部因剪应力较大容易产生破坏,采用分段跳挖的方式有助于保持基坑的稳定性,采用分层开挖的方式有助于减小基坑底部隆起量。建立的模型能够较为准确的模拟不同工况下基坑开挖对边坡稳定性影响,可以较好地对比出开挖方式对于维持边坡稳定性的优劣性,具有很好的借鉴意义。

This paper discusses the effect of different excavation sequence on the stability of the soil-rock dual structure formations.Four different excavation sequences were studied in a deep excavation project in Jingde,Jiangxi Province.The one-step,sequential stepped,skipped excavation and sequential skipped excavation are numerical simulated and are performed in the construction and the slope surfaces at each type of excavation were monitored.The monitored data indicated that the excavation would result in the gravitational stress redistribution at the bottom of the excavation.The sequential skipped excavation method would be beneficial to the stability of the excavated area.Whereas,the stepped excavation method would reduce the heave at the excavated area.Analyses of different excavation methods can accurately simulate the excavation sequence on the stability of the excavated slopes and the excavation method can be optimized.