宁波地铁5号线联络通道人工冻结法应用研究
Application of Artificial Freezing Method in the Connecting Passage of Ningbo Metro Line 5
范大军 1陈军 1庄兴岳 1黄朝煊2
作者信息
- 1. 浙江省地矿勘察院有限公司,浙江 杭州 310016
- 2. 浙江省水利水电勘测设计院有限责任公司,浙江 杭州 310002
- 折叠
摘要
随着人工冷冻技术的发展,人工冻结法(AGFM)已在地下空间建设中推广采用,依托宁波市轨道交通5 号线隧道联络通道冻结法施工工程,通过室内试验分别对土体起始冻结温度、导热系数、比热容系数、土层冻胀率及融沉率等进行试验研究,得出主要土层的导热系数与温度、比热容系数与温度、土层冻胀率与附加应力之间的线性拟合计算式,提出并建立人工冻结过程中考虑热物理参数随温度变化的热-力耦合的三维数值计算方法,并结合现场温度场、位移场等监测资料,得到宁波市轨道交通5 号线联络段主要控制土层粉质黏土层的最小冻结壁厚度为 1.79 m～2.38 m,冻结壁平均温度-12.13℃～-20.3℃,满足设计要求;现场四个监测断面点的位移收敛值均相对较小,最大位移收敛值不超过 4 mm,整体表明冻结法施工过程中冻胀力对隧道的影响较小,理论计算成果基本与现场实测规律吻合.
Abstract
With the development of artificial freezing technology,the artificial freezing method(AGFM)has been widely adopted in underground space construction.This work adopted the freezing method to Ningbo Metro Line 5 tun-nel,and conducted indoor experiments to determine the initial freezing temperature of the soil,specific heat capacity coefficient,frost heave rate of soil layer were tested and analyzed.Linear fitting calculation formula between thermal conductivity of the soil λ and temperature were proposed,and a three-dimensional numerical calculation method that considers the variation of thermal physical parameters with temperature during the artificial freezing process was adopted to determine the development of soil displacement and temperature during the artificial freezing process of the connect-ing section of Ningbo Metro Line 5.Through comparative analysis,the law is in good agreement with the on-site meas-urement,providing technical reference for similar engineering design and construction.
关键词
地铁联络通道/人工冻结法/数值计算/温度场/位移场/冻结壁Key words
subway connecting passage/artificial freezing method/numerical calculation/temperature field/displacement field/frozen wall引用本文复制引用
出版年
2024
NETL
NSTL
维普
万方数据