石膏岩隧道衬砌支护设计方案优化研究

Optimization research on design scheme of gypsum rock tunnel lining support

在地下工程建设过程中常会遭遇到大量不良地质区段,尤其是石膏岩等软弱膨胀性岩层,会对隧道衬砌产生极大危害。为此,迫切需要进行石膏岩隧道衬砌支护优化设计研究,建立相关评价方法。建立了围岩和支护稳定性评价办法及衬砌结构安全性评价办法,衬砌结构安全性通过钢筋混凝土结构的强度安全系数进行评价,围岩与支护稳定性通过强度折减法的系数评价。并基于某特长隧道石膏岩段工程案例,模拟原支护方案并采用该评价方法对衬砌支护进行优化。运用该评价方法可指导设计和施工的进行,使设计方案的稳定性、可靠性得到定量分析和较为准确的评价。

In the process of underground engineering construction,a large number of unfavorable geological sections will be encountered.Especially the expansive rocks such as gypsum rock will cause great damage to the tunnel lining.Therefore,it is urgent to carry out the optimization design of the gypsum rock tunnel lining support and establish relevant evaluation methods..The study established the evaluation method of surrounding rock and support stability and the safety evaluation method of lining structure.The safety of lining structure was evaluated by the strength safety factor of reinforced concrete structure,and the stability of surrounding rock and support was calculated by the factor evaluation of finite element strength reduction.Based on the case of a gypsum rock section of a special long tunnel,the working condition is simulated and the lining support is optimized by this evaluation method.The evaluation method can be used to guide the design and construction,so that the stability and reliability of the design scheme can be quantitatively analyzed and accurately evaluated.