都邠沟清淤工程岸坡稳定性分析

Stability Analysis of Bank Slope of Dubin River Dredging Project

为研究莆田市都邠沟清淤工程中施工岸坡的稳定性,文章针对其需要新建护岸的河道岸坡,采用有限差分软件FLAC;建立岸坡稳定性计算模型,分析施工岸坡从开挖到回填不同阶段的位移与应力变化。计算结果表明:岸坡施工,开挖面竖向位移在开挖后达到最大,岸坡Ⅰ位移16.70 mm,岸坡Ⅱ位移11.03 mm,随后逐渐减小。开挖面水平位移在整个施工过程中持续增加,土方回填完成时达到最大,岸坡Ⅰ位移值8.46 mm,岸坡Ⅱ位移值13.50 mm。岸坡Ⅰ开挖至淤泥质土层,最大位移发生在坡脚处,岸坡Ⅱ开挖超过淤泥质土层,岸坡最大位移发生在坡面上的淤泥质土层最下部。岸坡开挖后的最大主应力减小明显,施工阶段岸坡均未产生拉应力。

In order to study the stability of the construction bank slope in the Dubin River in Putian City,the finite difference software FLAC3D is used to establish a calculation model of bank slope stability,and the displacement and stress changes of bank slope at different stages from excavation to backfilling were analyzed.The calculation results show that the vertical displacement of the excavation surface reaches the maximum after excavation.The displacement of the bank slope I is 16.70 mm,the displacement of the bank slope II is 11.03 mm.Then the the data gradually decreases.The horizontal displacement of the excavation surface continued to increase during the entire construction process.It reaches the maximum when the earth backfilling is completed,with a displacement value of 8.46 mm for bank slope I and 13.50 mm for bank slope II.The maximum displacement of bank slope I occurs at the foot of the slope,while the maximum displacement of bank slope II occurs at the bottom of the silt soil when the bank slope I is excavated to the silt soil.The maximum principal stress of the bank slope decreases ovbiously after excavation.No tensile stress occurs in bank slope during construction stage.