摘要
研究目的:采用带有分项系数的实用设计表达式,不仅能继承传统结构设计式的形式,而且能体现结构设计对目标可靠指标的要求,是应用可靠指标衡量结构设计安全水平的重要途径。本文根据铁路隧道衬砌结构的受力特点和材料性能,采用混凝土衬砌结构抗压、混凝土衬砌结构抗裂和钢筋混凝土衬砌结构三种极限状态设计式建立"荷载-结构"模型。研究结论:利用Monte-Carlo随机有限元的方法分析铁路隧道衬砌结构作用效应的统计特征,根据材料特性分析抗力的概率统计特征以及计算可靠指标与目标可靠指标差值最小化的原则,分析得到:(1)铁路隧道衬砌结构检算时,围岩压力分项系数为1.4,自重荷载分项系数为1.2;(2)钢筋混凝土、混凝土抗压、混凝土抗裂三种工况下的调整系数分别为1.05、1.85、2.35;(3)该研究结果可为《铁路隧道设计规范》的修订提供理论依据。
Research purposes： The practical design expression with a pa^ial coefficient, not only inherited the form of traditional structural design, but also reflected the structural design requirements for the target reliability index. It is the important way to measure the level of structure security with application of a reliable indicator. According to the stress characteristics and material properties of railway tunnel lining structure, the load - structure model is established using the three kinds of limit states design equations of the compressive concrete lining structure, the anti - cracking concrete lining structure and reinforced concrete lining structure. Research conclusions：The statistical characteristic of railway tunnel lining structure effect is analyzed using Monte - Carlo stochastic finite element method, according to the probability statistical characteristics of material characteristic resistance and difference minimization principle between the calculated reliability index and the target reliability index, the following conclusions are analyzed： （1） The railway tunnel lining structure is checked, the surrounding rock pressure partial coefficient is 1.4, gravity loads of reinforced concrete, concrete compressive partial strength coefficient is 1.2. （2） The three kinds of adjustment coefficients , concrete anti - cracking coefficient are 1.05, 1.85, 2.35. （3） The calculation results can provide theoretical basis for the railway tunnel design code revision.
出处
《铁道工程学报》
EI
北大核心
2015年第6期57-61,共5页
Journal of Railway Engineering Society
基金
铁道部科技研究开发项目(2012G014-D)
中国中铁股份有限公司科研项目[13164174(12-14)]
关键词
隧道衬砌结构
极限状态设计式
分项系数优化
tunnel lining structure
limit states design equations
partial coefficient optimization
