从当前铁路隧道衬砌典型病害谈设计施工改进措施

Discussion on Design and Construction Improvement Measures Based on Current Typical Diseases of Railway Tunnel Lining

铁路隧道对运营安全性要求极高,特别是高速铁路隧道。通过系统研究分析隧道衬砌典型病害(仰拱上拱、涌水、拱顶掉块风险)的原因,提出设计施工需改进的工程技术措施建议:1)仰拱上拱的主要原因是地下水、构造应力、膨胀力、施工质量、结构刚度不足等,建议采取加强隧底防排水、加大仰拱矢跨比、加强仰拱结构刚度和强度、确保仰拱施工质量等措施; 2)涌水的主要原因是岩溶等复杂的水文地质条件、排水设施未充分发挥作用、施工质量缺陷等,建议采取加强水文地质勘察及施工地质评估、优化排水设计、提高衬砌施工质量、加强运营维护管理等措施; 3)拱顶掉块风险的主要原因是拱部衬砌存在空洞、厚度不足、施工缝缺陷等,建议采取优化施工缝结构设计、加强开挖和防水板铺设质量控制、配备先进工装设备等措施。

Railway tunnels have high requirements for operation safety,especially for high-speed railway tunnels.The typical diseases of tunnel lining,i.e.inverted arch uplift,water gushing and risk of crown top spalling,are analyzed by systematical research,and suggestions on technical measures for improvement of design and construction are put forward.The advices include:(1)The main reasons for inverted arch uplift are groundwater,tectonic stress,expansion force,construction quality and insufficient structural stiffness;it is suggested to take measures such as strengthening the waterproof and drainage of tunnel bottom,increasing the rise-span ratio of inverted arch,strengthening the stiffness and strength of inverted arch structure,and ensuring the construction quality of inverted arch.(2)The main reasons of water gushing are complex hydrogeological conditions such as karst,underutilized drainage facilities and construction quality defects;and it is suggested to take measures such as strengthening hydrogeological investigation and construction geological assessment,optimizing drainage design,improving construction quality of lining,and strengthening operation and maintenance management.(3)The main reasons of the risk of crown top spalling are holes of arch lining,insufficient lining thickness and defects in construction joints;and it is suggested to take measures such as optimizing the structural design of construction joints,strengthening the quality control of excavation and waterproof plate laying,and equipping with advanced tooling equipment.