高内压作用下叠合式衬砌结构承载机理原型试验研究  

The bearing mechanism of superimposed linings structure under high inner hydraulic pressure:a prototype experimental study

作　　者：刘庭金[1,3] 陈高敬 唐欣薇[1] 张武[2] 黄鸿浩 姚广亮 LIU Tingjin;CHEN Gaojing;TANG Xinwei;ZHANG Wu;HUANG Honghao;YAO Guangliang(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,China;Guangdong Hydropower Planning and Design Institute,Guangzhou 510635,China;State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学土木与交通学院,广东广州510640 [2]广东省水利电力勘测设计研究院,广东广州510635 [3]华南理工大学亚热带建筑科学国家重点实验室,广东广州510640

出　　处：《水利学报》2020年第3期295-304,共10页Journal of Hydraulic Engineering

基　　金：国家自然科学基金项目(51678248,51878296)。

摘　　要：本文针对“外衬管片-自密实混凝土填充层(SCC)-内衬钢管”三层叠合式输水隧洞衬砌结构的承载性能及破坏机理,开展了结构在内外载联合作用下的原型试验。试验以分布式光纤感测技术作为主要测量手段,获得了加载过程中SCC层的裂缝扩展情况、接缝张开变形、螺栓应力与内衬钢管环向应变的发展历程。试验结果表明:在无内压工况下,结构整体呈弹性工作状态;在内压变化工况下,当内压低于0.6 MPa时,结构整体保持弹性,三层衬砌共同承担内压;当内压达到0.6 MPa时,SCC层开裂,内压快速向外衬管片转移,结构整体进入弹塑性阶段;随着内压继续增大,管片接缝螺栓在内压为0.965 MPa时屈服,外衬逐渐失去分担内压能力,结构体系进入破坏阶段,内水压力主要由内衬钢管承担。试验研究成果可为实际工程设计提供指导和参考。In this paper,to investigate the bearing capacity and the failure mechanism of the water convey ance tunnel of concrete segment-self compacted concrete(SCC)-steel tube superimposed linings under the combination loading of the inner hydraulic pressure and the external pressure,a full-scale experimental test was conducted.Taking the distributed fiber optical sensing technology as the main measurement meth od,the development of the cracks of the SCC,the joint opening magnitude,the bolt stress and the devel opment of the circumferential strain of the steel lining during the whole test process are presented.Some conclusions can be drawn from the experimental results as follows.Firstly,without being subjected to inner hydraulic pressure,the mechanical behavior of the structure shows elastic property.Secondly,as for the variable inner hydraulic pressure,when the inner hydraulic pressure was less than 0.6Mpa,the SCC re mains elastic and the loading was carried by all linings.Thirdly,when the inner hydraulic pressure reached 0.6Mpa,the SCC layer cracked and the inner hydraulic pressure transferred to the outer lining rap idly,which indicated that the mechanical behavior of the structure entered the elastic-plastic phase.Final ly,as the inner hydraulic pressure increased,the segment joint bolt yielded when the inner pressure reached 0.965Mpa.Meanwhile,the outer lining gradually lost its bearing capacity and the inner pressure was mainly carried by the inner steel tube,which demonstrated that the structure entered the failure phase.The conclusions obtained from the experimental results can provide the guideline and references for the de signing.

关 键 词：输水隧洞 叠合式衬砌 高内压 承载机理 原型试验 分布式光纤 

分 类 号：TV554[水利工程—水利水电工程]