钢拱架应力反分析隧道初期支护力学性能的研究  

Back analysis for the mechanical properties of initial tunnel support based on steel arch stresses

作　　者：文竞舟[1,2] 张永兴[1,2] 王成[3] 姜兆华[1,2] 

机构地区：[1]重庆大学,重庆400045 [2]重庆大学山地城镇建设与新技术教育部重点实验室,重庆400045 [3]重庆交通大学,重庆400074

出　　处：《土木工程学报》2012年第2期170-175,共6页China Civil Engineering Journal

基　　金：国家杰出青年科学基金(50625824);黔科合重大专项字([2008]6018)

摘　　要：适时分析软弱破碎围岩段衬砌结构的内力状态是隧道动态施工中的关键性问题之一,对判断隧道施工安全状态和评价支护结构稳定性具有重要意义。考虑钢拱架已作为软弱围岩段公路隧道初期支护的重要形式,现通过分析隧道施工现场钢拱架支护的自身特点和受力特性,建立含有钢拱架和喷射混凝土的隧道复合初期支护的地基曲梁力学模型。然后运用地基曲梁相关理论,通过现场监测的钢拱架应力推求出隧道复合初期支护内力解析式,从而迅速得到隧道支护结构的应力集中部位。最后,经由台阶法施工的隧道工程实例运用表明,基于实测钢拱架应力求解隧道初期支护内力的解析研究是分析软弱破碎围岩段隧道支护力学性能的一种新方式,并能及时有效地为隧道现场施工安全提供直观、可靠的力学依据和技术支持。Prompt analysis of the internal force of tunnel lining in weak-broken surrounding rocks is one of key problems for tunnel construction, useful for identification of construction safety state and evaluation of stability of the support system. Steel arch support would be used as an important primary support of tunnel when the surrounding rock is weak and/or broken. According to its characteristics and mechanical properties in-situ, a mechanical model of steel arch and shotcrete is established. Analytical solutions of the internal force of the composite support are deduced based on the theory of circular beam on elastic foundation and steel arch stresses measurement. As a result, stress concentrated parts of tunnel lining can be quickly identified. An example of a tunnel excavated by using the bench method verified the method.

关 键 词：公路隧道 软弱破碎围岩 复合初期支护 钢拱架应力 弹性地基曲梁 

分 类 号：TU452.12[建筑科学—岩土工程] U455.72[建筑科学—土工工程]