管幕冻结法冻结过程温度场数值模拟  

Numerical Simulation of Temperature Field in Freezing Process with Pipe Roof Freezing Method

作　　者：卢亦焱[1] 张宏 魏龙海[2] 黄晓剑[1] 

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072 [2]中交第二公路勘察设计研究院有限公司,湖北武汉430056

出　　处：《铁道建筑》2017年第12期52-54,58,共4页Railway Engineering

基　　金：湖北省技术创新专项重大项目(2016AAA025)

摘　　要：对港珠澳大桥珠海连接线拱北隧道管幕冻结过程进行了有限元数值模拟,分析了冻结管布置圈整体温度场及冻结帷幕厚度随时间的变化规律。结果表明:冻结过程中形成了以冻结管布置圈为中心的环形温度场,冻结管布置圈内的土体温度下降速度快于布置圈外,其最终温度也要低于布置圈外;在冻结30 d左右相邻冻结管的冻结范围开始重叠,形成了0℃以下的冻结圈;冻结48 d左右基本形成了连续的、具有一定厚度的冻结帷幕;冻土壁厚度达到顶管间止水要求的1.45 m的时间点在冻结72~84 d之间。Finite element numerical simulation for pipe roof freezing process of Gongbei tunnel in Zhuhai connection line of Hong Kong-Zhuhai-Macao Bridge was made,and the change laws for overall temperature field of the freezing pipe arrangement circle and thickness of frozen curtain with time changing were analyzed.The results show that a ring temperature field centered on the freezing pipe arrangement circle is formed in freezing process,the descending speed of soil temperature inside freezing pipe arrangement circle is larger than that outside the arrangement circle,the final temperature inside freezing pipe arrangement circle is also lower than that outside the arrangement circle. The freezing range of adjacent freezing pipes overlaps and forms a freezing circle below 0 ℃centigrade at about 30 freezing day.A continuous frozen curtain with a certain thickness is basically formed at about 48 freezing day,and the time point of the permafrost wall thickness reaches 1. 45 m and meets the water stop requirements between jacking pipes is between 72 d and 84.

关 键 词：公路隧道 冻结帷幕 数值分析 管幕 温度场 

分 类 号：U453.6[建筑科学—桥梁与隧道工程]