基于冻结器温升公式的单排管温度场求解方法  

A method for solving temperature field of single-row freezing pipe based on temperature rise formula of freezer

作　　者：张松 周晓敏 张基伟 孙钦帅 刘勇 马文著 徐宏毅 ZHANG Song;ZHOU Xiaomin;ZHANG Jiwei;SUN Qinshuai;LIU Yong;MA Wenzhu;XU Hongyi(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Beijing Municipal Engineering Consulting Corporation,Beijing 100025,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]石家庄铁道大学土木工程学院,河北石家庄050043 [3]北京北咨工程项目管理咨询有限公司,北京100025

出　　处：《铁道科学与工程学报》2024年第3期1102-1113,共12页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51678048)。

摘　　要：为了解决传统地铁联络通道冻结法施工中对于全加固区域温度场求解精度不足的问题,实现以冻结器自身温度信号进行所形成温度场求解,达到对冻结温度场全域进行精准求解的目的。从单根冻结管停冻后冷媒温度回升速率与冻结壁厚度的相互关系出发,建立更加符合地铁联络通道冻结工程特点的单排冻结孔温度场计算模型,提出了5个关键参数:冷媒温升速率V、冻结壁厚度计算系数ηA和ηB以及冻结壁厚度修订系数n1和n2的确定方法。并指出冷媒温升速率宜采用停冻后4 h的冷媒温度平均回升速率,冻结壁计算系数和厚度修订系数应采用数值计算或经验数据进行确定。进而提出了新温度场求解方法的适用范围、求解流程。后续利用北京某联络通道冻结工程开展新温度场求解方法的可靠性验证。通过将该联络通道侧墙区域温度场的求解结果和实测地层数据进行对比可知,新的温度场求解方法所得温度与测温孔实测温度差值分别为0.43℃和0.52℃,远低于控制指标1.0℃。同时,新求解方法所得冻结壁厚度与开挖后实测冻结壁厚度误差为8~10 cm,误差精度约为6%,符合工程精度要求。此外基于计算结果和现场分析,指出了计算误差主要是由于地层热物理参数测试精度不足、钻孔偏斜以及冻结管自身结构简化三方面造成的。同时根据既有研究成果,给出了我国多个城市(如上海、常州、苏州)典型地层的冻结壁厚度计算系数。本研究为新型温度场计算方法的落地实施和开展基于冻结器自身温度数据进行全域温度场求解提供了理论支撑,同时避免了传统“以点带面”式求解方法带来的非测温孔区域温度误差。To solve the problem of the calculation insufficient accuracy in traditional analytical solution for the artificial ground freezing temperature field of the whole freezing area in the metro cross passage.At the same time,it established the analytical solution by the freezer’s temperature data.Moreover,realize the accurate solution of the whole area temperature field.The calculation model for the freezing temperature field of a single row freezing pipe fitter to the temperature distribution characteristics of the meter cross passage artificial ground freezing project was established based on the relationship between the rate of temperature rise of the refrigerant after stopping freezing in the freezing pipe and the thickness of the frozen curtain generated by the same freezing pipe.Then five critical parameters in the new method were proposed.They are the refrigerant temperature rise rate V,the calculation coefficient of the frozen curtain thicknessη_(A) andη_(B),and frozen curtain thickness revision factors n1 and n2.While the methods to determine these parameters were given.Among them,the refrigerant temperature rise rate V should use the average temperature rise rate of the refrigerant at four hours after stopping freezing.Furthermore,the calculation coefficient of the frozen curtainηA andηB,the frozen curtain thickness revision factors n1 and n2 could be determined by numerical calculation or empirical data.Furthermore,the new temperature method applied scope and solution process was proposed.In the end,the reliability verification of the new temperature field solution method was carried out through a cross passage freezing project in Beijing.By comparing the solution results of the side wall temperature field of the cross passage with the measured temperature data,it can be seen that the temperature obtained by the new temperature field solution method and the measured temperature difference of the temperature measurement pipe was 0.43℃and 0.52℃,respectively,which are far lower than the control inde

关 键 词：人工冻结法 全域温度场 精准求解 计算流程 联络通道 

分 类 号：TU443[建筑科学—岩土工程]