浅埋高压钢筋混凝土岔管安全性分析

浅埋高压钢筋混凝土岔管结构一般受力复杂,其安全与否不仅仅是衬砌结构强度满足要求,还要考虑到施工和运营过程中围岩的稳定;最小覆盖层厚度;渗透失稳及水力劈裂等多项安全性能。利用三维非线性有限元数值分析方法,对某浅埋高压混凝土岔管进行了非线性仿真模拟,得到了各施工步衬砌结构、围岩及支护的情况。对衬砌裂缝及多项安全性进行了分析,结果表明:采用边开挖、边喷锚,衬砌一次成形的施工工序基本合理。结构在运行阶段,岔裆处将出现裂缝,最小覆盖层厚度满足要求,不会发生渗透失稳,但在岔裆处将发生一定规模的水力劈裂。

Safety analysis on shauow embedded high-pressure reinforced concrete bifurcated pipe

The nonlinear 3-D finite element simulation is made on a shallow embedded high-pressure reinforced concrete bifurcated pipe,as the structure of shallow embedded high-pressure reinforced concrete bifurcated pipe is generally under a complicated stress condition;from which the lining structure,surrounding rock and supporting status of each construction phase of the pipe are obtained;and then the lining cracks and the safeties of some related items are analyzed as well.The results show that the construction process of finishing excavation,shot-anchoring and lining at one time continuously is basically reasonable.However,some cracks are to be formed at the fork of the bifurcated pipe along with a certain scale of hydraulic fracture;nevertheless,the minimum thickness of the coverage can meet the requirement concerned and no seepage failure will occur.