水工隧洞混凝土衬砌地震动响应过程分析

发布时间：2018-06-12 23:44

本文选题：水工隧洞 + 混凝土衬砌　；参考：《工程科学与技术》2017年02期

【摘要】：地震作用下水工隧洞混凝土衬砌结构的动态响应是工程设计和安全评估的重要内容,建立科学合理的混凝土动力本构模型以及内水与衬砌动力耦合作用分析方法是衬砌结构抗震研究的关键环节。基于应变空间静力损伤本构的基本思路,对3维应力状态下混凝土静态拉、压损伤变量进行定义和求解;在此基础上,考虑静、动态荷载作用下混凝土本构关系曲线的相似性特点,建立了适宜编程的混凝土动态损伤本构模型。基于单相固体介质和流体介质动力分析的显式有限元法,结合耦合界面的边界条件,建立了水工隧洞内水与衬砌耦合作用的动力显式有限元分析模型,该方法可以直接进行逐步积分,无需联立方程组求解,大大简化了计算过程,可以方便地用于分析多种介质的波动传播问题。针对某水电站引水隧洞工程进行了实例分析,计算结果表明:1)各部位混凝土衬砌处于同步震动状态,但腰拱部位位移明显小于顶拱和底拱部位;2)地震作用下混凝土衬砌迅速进入损伤开裂状态,腰拱部位衬砌应力增加明显,损伤破坏严重;3)开裂破坏区由腰拱逐渐向两端扩展,与内水直接作用的内层衬砌结构是抗震设计的薄弱环节。该模型能够合理地反映水工隧洞混凝土衬砌的地震动响应特性,并为水工隧洞抗震设计提供了一种有效的分析方法。
[Abstract]:The dynamic response of concrete lining structure of hydraulic tunnel under earthquake is an important part of engineering design and safety assessment. Establishing a scientific and reasonable concrete dynamic constitutive model and the analysis method of the dynamic coupling between internal water and lining are the key links in the seismic research of lining structure. Based on the basic idea of static damage constitutive theory in strain space, the static tensile and compressive damage variables of concrete under three dimensional stress are defined and solved. Based on the similarity of constitutive curve of concrete under dynamic load, a suitable dynamic damage constitutive model of concrete is established. Based on the explicit finite element method for the dynamic analysis of single phase solid and fluid media and the boundary conditions of the coupled interface, a dynamic explicit finite element analysis model for the coupling of water and lining in a hydraulic tunnel is established. This method can be used to solve the problem of wave propagation in many kinds of media directly, without solving simultaneous equations, which greatly simplifies the calculation process. An example analysis of diversion tunnel project of a hydropower station is carried out. The calculation results show that concrete lining is in synchronous vibration state in every part of the concrete lining. However, the displacement of the waist arch is obviously smaller than that of the top arch and the bottom arch. Under the earthquake, the concrete lining rapidly enters into the state of damage and cracking, and the stress of the lining in the waist arch increases obviously, and the damage area expands gradually from the waist arch to the two ends. The inner lining structure acting directly with inner water is a weak link in seismic design. The model can reasonably reflect the ground motion response of hydraulic tunnel concrete lining and provide an effective analysis method for seismic design of hydraulic tunnel.
【作者单位】：武汉大学水资源与水电工程科学国家重点实验室;武汉大学水工岩石力学教育部重点实验室;
【基金】：国家重点基础研究发展计划(“973”)资助项目(2015CB057904) 国家自然科学基金资助项目(51579191);国家自然科学基金资助项目(51279136)
【分类号】：TV312;TV672.1

【相似文献】