高拱坝施工期横缝增开现象及其相关成因研究  

Study on abrupt gape of transverse joints and its cause during construction of high arch dams

作　　者：胡昱[1] 左正[1] 李庆斌[1] 罗丹旎 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点实验室,北京100084

出　　处：《水力发电学报》2013年第5期218-225,共8页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金(51279087);国家973项目(2013CB035902);清华大学水沙科学与水利水电工程国家重点实验室科研课题(2011-KY-4)

摘　　要：高拱坝施工期横缝开合度变化较复杂,实际工程中出现了一种特殊的横缝增开现象,具有非常明显的同时性和普遍性,并可能对坝体已灌浆部位造成不利影响。本文通过对工程实例的分析与总结,提出了缝面蓄能的概念,指出缝面蓄能过多、通水检查等外因诱导是横缝增开现象的主要成因。本文利用双层有厚度横缝单元对实际工程进行了仿真模拟与数值试验,计算结果说明考虑横缝单元的生死能够有效模拟该现象,数值试验也指出保证横缝在理想时段的及时拉开可以预防横缝增开现象的发生。Opening and closing of transverse joints during construction of high arch dams are very complicated, and in some projects the joint apertures have showed abnormal behavior called abrupt gape. These joints, distinguished with two obvious features, synchronization and universality, may have unfavorable effects on grouted area. To explain the abrupt joint gape, this paper proposes a concept of tension energy of joint interface. Analysis on practical projects indicates that high tension energy and external forces such as pressure water checking are the major causes of abrupt joint gape. A simulation of transverse joints for a high arch dam by adopting 3D double joint elements of finite thickness is presented in this paper, and it is shown that abrupt gape can be successfully modeled through activating and deactivating the 3D joint elements. Numerical experiments indicate that pulling the transverse joints open in an ideal period is an effective measure to avoid the gape problem.

关 键 词：水工结构 横缝增开 测缝计 高拱坝 

分 类 号：TV331[水利工程—水工结构工程]