寒区隧道洞口保温层设防长度确定方法探讨  

Discussion on the Methods to Determine the Laying Length of the Insulation Layer at Tunnel Portals in Cold Region

作　　者：吴剑[1,2] 郑波 方林[3] 匡亮 郭瑞 WU Jian;ZHENG Bo;FANG Lin;KUANG Liang;GUO Rui(China Railway Southwest Research Institute Co.,Ltd.,Chengdu 611731,China;Sichuan Provincial Engineering Technology Research Center of Tunnel Safety,Chengdu 611731,China;National Engineering and Research Center for Mountainous Highways,Chongqing 400067,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]中铁西南科学研究院有限公司,成都611731 [2]四川省隧道安全工程技术研究中心,成都611731 [3]国家山区公路工程技术研究中心,重庆400067 [4]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道标准设计》2021年第10期81-86,共6页Railway Standard Design

基　　金：四川省重点研发计划项目(2018GZ0359);国家山区公路工程技术研究中心开放基金(GSGZJ-2017-01);中国中铁股份有限公司科技开发计划项目(CZ01-重大-01)。

摘　　要：高海拔寒冷地区隧道冬季常因低温环境影响导致洞口段产生衬砌开裂、挂冰等冻害问题,如何科学合理地确定寒区隧道洞口保温层设防长度是寒区隧道安全运营的关键。以雀儿山隧道为例,基于现有不同的保温层设防长度确定方法得到洞口保温层设防长度,并结合现场测试对比分析各种方法确定的设防长度值,探讨其优缺点。同时研究提出,针对两端洞口环境条件相似情况,在黑川希范公式中引入一个海拔系数;对洞口两端环境存在显著差异情况,特别是隧道内存在单向自然风情况,引入环境影响量,并在此基础上得出适用于高海拔隧道保温层设防长度计算的修正经验公式。During winter,such freeze disasters as lining cracks and icings often occur at tunnel portal section due to the influence of lower temperature on high-altitude tunnels in cold region.How to scientifically and reasonably determine the fortified length of the insulation layer at tunnel portals in cold region is the key to the safety operation of the tunnel in cold region.This paper,taking the Queershan Tunnel as an example,obtains the laying length of the insulation layer at tunnel portal based on existing methods.According to field tests,the laying length values determined by various methods are compared and analyzed,and then the merits and demerits of various methods are discussed.The similar environmental conditions at both portals of tunnel are studied and proposed and an altitude coefficient is introduced into Kurokawa Sivan formula.Significant environmental differences exist at both portals of the tunnel,and especially,the unidirectional natural wind exists in the tunnel,which introduces an environmental impact.On this basis,a modified empirical formula suitable is obtained for calculating the laying length of insulation layer in high-altitude tunnels.

关 键 词：寒区隧道 纵向温度场 保温防冻长度 海拔系数 环境影响量 确定方法 

分 类 号：U453[建筑科学—桥梁与隧道工程]