摘要
通过对喷射混凝土的实际受力机制以及隧洞施工过程响应特征的研究,发现喷混凝土的施工和受力过程具有非常复杂的时间和空间效应。研究表明:喷混凝土支护结构的受力会随着隧洞掌子面的推进而越来越大;喷混凝土从初喷到复喷,直至达到设计强度,其变形和强度的力学特性是随着时间而逐渐变化的,即混凝土的起强过程;喷混凝土与围岩间接触面的力学性质也随时间发生变化;支护结构设计分析中,若不考虑喷混凝土施工和力学特性的时间和空间效应,将会高估喷混凝土的实际受力状态。通过以色列Kokhav Hayarden抽蓄电站施工支洞喷混凝土设计的实际应用,证明了隧洞喷混凝土支护设计计算中考虑其时间和空间效应是必要的,否则将会高估其实际受力。
Through the study of the actual force mechanism of the shotcrete and response characteristic of tunnel during the construction,it is found that the construction and stress process of the shotcrete has a complicated time and space effect.The results show that:the force of shotcrete support structure will become more and more larger with the propulsion of the palmar surface of the tunnel,and the mechanical properties of the deformation and strength of shotcrete change from the beginning to the secondary spray,until the design strength is reached;The mechanical properties of the contact surface between the shotcrete and the rock mass also change gradually with time;In the design and the analysis of support structure,if the time and space effect of shotcrete construction and mechanical properties are not taken into account,the actual stress of the shotcrete will be overestimated.Through the practical application of the shotcrete design of the adit tunnel in Kokhav Hayarden pumped storage project in Israel,it is proved that it is necessary to consider its time and space effect in the design calculation of shotcrete support in tunnel,and otherwise it will overestimate its actual force.
作者
徐全
吴家耀
褚卫江
曹爱武
刘加进
Xu Quan;Wu Jiayao;Chu Weijiang;Cao Aiwu;Liu Jiajin(PowerChina Huadong Engineering Corporation,Hangzhou 311122,P.R.China;Hydrochina ITASCA Research and Development Center,Hangzhou 310000,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2020年第3期852-862,共11页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(51679215)。
关键词
喷层
力学特性
时空效应
抽水蓄能
shotcrete
mechanical properties
time and space effect
pumped storage
