隧道衬砌厚度不足对衬砌结构承载力影响

摘要

The purpose of this paper is to explore the structure safety and bearing capacity of a certain city tunnel,and to explore whether the tunnel will be affected by the thickness of the lining or lining thinning.Through the simulation experiment,select the typical lining section as the research object,measure of safety factors weights by AHP,the model of bearing capacity and deformation analysis of the lining thickness insufficient in different degrees.When the actual results and design of lining thickness ratio decreased from 0.9 to 0.5,the deformation value increased from 18 mm to 45 mm.when the ratio is less than 0.7 when the maximum vertical bearing capacity,the safety coefficient decreases obviously,reduce the safety factor;when the ratio is more than 0.7,the structure is safety.%目的 对某城市隧道检测,探究隧道是否会因衬砌厚度不足或衬砌减薄而对结构安全及承载力造成影响.方法 通过模拟实验,选取典型的衬砌断面为研究对象,用层次分析法衡量安全因素权重值,建立模型对不同程度的衬砌厚度不足情况进行承载力和变形分析.结果 当实际衬砌与设计厚度比值从0.9降到0.5时,最大竖向变形值从18mm增加到45 mm;当其比值小于0.7时,其承载力安全系数显著减小,结构安全系数降低;当比值大于0.7时,结构安全.结论 衬砌厚度在不同工况下,结构承载力和安全性随着衬砌厚度与实际厚度的比值减小而减小.隧道衬砌厚度达不到设计要求会削弱结构的承载能力且影响其正常使用.