基于强度折减法的镇压层对海堤稳定性的影响

Effect of repressive layer on stability of seawall based on strength reduction method

镇压层对软土地基上海堤稳定性提升具有重要作用,但其宽度、厚度的选择大多凭经验公式以及极限平衡法进行选择和计算。基于强度折减法,利用ABAQUS有限元软件对镇压层的宽度、厚度与海堤安全系数之间关系进行研究。首先介绍强度折减法的基本原理,之后建立相关海堤模型。将镇压层宽度及厚度以线荷载宽度及大小的形式添加到模型中,以数值计算收敛与否作为评价标准计算得到安全系数以及潜在滑动面。从滑动面角度分析安全系数与镇压层宽度变化的原因。结果表明:海堤稳定性与镇压层宽厚及厚度成正比关系,且宽度超过一定值后,安全系数以及滑动面均不再发生改变。

The repressive layer plays an important role in improving the stability of the seawall on the soft soil foundation,but the width and thickness are mostly calculated and selected by empirical formula and limit equilibrium method.Based on the strength reduction method,this paper studies the relationship between the width and thickness of the repressive layer and the safety factor of the seawall by using ABAQUS finite element software.First,the basic principle of strength reduction method is introduced.Then the relevant sea wall model is established.The width and thickness of the repression layer are added to the model in the form of the width and size of the linear load,and the safety factor and the potential sliding surface are calculated by taking the convergence of numerical calculation as the evaluation standard.The reasons of the change of safety factor and width of repressive layer are analyzed from the angle of sliding surface.The results show that the stability of the seawall is proportional to the width and thickness of the repressive layer,and the safety factor and the sliding surface do not change after the width exceeds a certain number.