静动载耦合作用仰拱混凝土损伤特征的试验研究  

Experimental study on static and dynamic load for cumulate damage characteristics of tunnel invert concrete

作　　者：刘宁[1] 彭立敏[1] 施成华[1] 

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《铁道科学与工程学报》2016年第10期1977-1984,共8页Journal of Railway Science and Engineering

基　　金：国家自然科学基金煤炭联合基金资助项目(U1361204);国家自然科学基金资助项目(51278494)

摘　　要：围岩压力和列车动载共同影响隧道仰拱结构的长期服役状态,目前,对于静载与动载耦合作用下仰拱累积损伤特征及规律的相关研究明显不足且未引入设计规范。基于此,开展用于描述不同静载引起仰拱混凝土动力累积损伤特征的试验研究,得到满足仰拱结构力学环境的混凝土累积损伤模型及仰拱累积损伤计算方法,并得到引起仰拱混凝土损伤破坏的静载力阀值。进行对不同静载条件下仰拱混凝土损伤演化规律的对比分析,给出不同工况及不同阶段损伤演化趋势的定量表达式,探明混凝土试件损伤主要分布在中间受拉区域,底部损伤值相对较大并最终发生破坏。Common actions of surrounding rock pressure and dynamic loading affects the service life of tunnel in-vert. However, the relevant theories research on accumulate damage behavior causing by static and dynamic load-ing are still limited and not included in current design codes. The experimental research presents a accumulate damage mode for describing the damage behavior of invert concrete due to static and cyclic load in tunnel envi-ronments. On the one hand, the damage model is already validated and the damage calculating method is ob-tained. On the other hand, this paper presented the threshold of the critical static load level causing the failure of the specimen. Moreover, comparison of the different static load level causing the damage of the specimen and the quantitative expression of the damage process is presented in this paper. The evolution of initial damages appeared first at the bottom centre of specimen and new damages will then form upward progressively.

关 键 词：累积特征 仰拱混凝土 循环荷载 静载 

分 类 号：U25[交通运输工程—道路与铁道工程]