波纹钢-混凝土组合明洞在双线铁路隧道洞口防护中的应用  

Application of Corrugated Steel⁃Concrete Composite Open Cut Tunnel in Portal Protection Engineering of Double Track Railway Tunnel

作　　者：王君顺 WANG Junshun(Lanzhou Railway Survey and Design Institute Co.Ltd.,Lanzhou 730070,China)

机构地区：[1]兰州铁道设计院有限公司,兰州730070

出　　处：《铁道建筑》2021年第9期68-72,79,共6页Railway Engineering

摘　　要：针对双线铁路隧道洞口的落石问题,提出采用波纹钢-混凝土组合式明洞结构加以防护,并结合兰青铁路二线一隧道洞口工程建立波纹钢-混凝土组合式明洞结构数值模型,进行明洞结构抗冲击荷载的数值计算,分析不同冲击能量下明洞结构受力变形特征。结果表明:落石冲击作用下,明洞结构的变形及应力响应均大于自重作用工况,落石冲击力是组合式明洞结构设计的关键荷载;随着冲击能量的增加,组合式明洞结构位移、应力的最大值均呈线性增加,混凝土材料主拉应力趋近于材料强度设计值,而波纹钢板应力远小于屈服强度;对于该工程,波纹钢-混凝土组合式明洞结构的抗冲击性能为70 kJ,明洞结构受力及变形可控;波纹钢-混凝土组合式明洞与既有隧道洞口连接方便,各构件均可现场预制加工,安装拼接时间短,施工工效高,适用于场地条件受限、须落石防护的隧道洞口工程,尤其是快速抢修抢建工程。In view of the rockfall problem at the portal of double track railway tunnel,the corrugated steel-concrete composite open cut tunnel structure was proposed.Combined with one tunnel portal project of the second line in Lanzhou-Xining railway,the numerical model of corrugated steel-concrete composite open cut tunnel structure was established,the numerical calculation of impact load resistance of open cut tunnel structure was carried out,and the stress and deformation characteristics of open cut tunnel structure under different impact energy were analyzed.The results show that the deformation and stress response of open cut tunnel structure under rockfall impact are greater than that under self-weight,and the rockfall impact force is the key load in the design of composite open cut tunnel structure.With the increase of impact energy,the maximum displacement and stress of the composite open cut tunnel structure increase linearly,the main tensile stress of concrete material approaches the design value of material strength,and the stress of corrugated steel plate is far less than the yield strength.For this project,the impact resistance of corrugated steel-concrete composite open cut tunnel structure is 70 kJ,and the stress and deformation of open cut tunnel structure are controllable.The corrugated steel-concrete composite open cut tunnel is easy to connect with the existing tunnel portal.All components can be prefabricated on site.It has short installation and splicing time and high construction efficiency.It is suitable for tunnel portal projects with limited site conditions and rock fall protection,especially rapid repair and construction projects.

关 键 词：铁路隧道 隧道洞口 数值模拟 波纹钢-混凝土组合明洞 落石 冲击能量 

分 类 号：U457.2[建筑科学—桥梁与隧道工程]