高速铁路隧道仰拱隆起病害分析及整治方案

近年来仰拱隆起病害时有发生,影响隧道的运营和行车安全。本文结合地质情况,对云贵高原上一高速铁路隧道在运营期内出现仰拱变形隆起现象进行分析,认为引起轨道抬升的主要因素是高地应力作用及隧底围岩在地下水和列车动荷载作用下日益软弱。采取拆除隧道仰拱并加深1.5 m重构的方案进行综合整治。用MIDAS GTS/NX对原设计及整治设计方案进行数值模拟分析,验证了仰拱加厚加深方案可使隧道拱顶沉降、仰拱隆起、应力等减小,符合要求。制定了施工过程中不同工况下隧道及轨道监测方案,确保施工期间运营安全。

Cause Analysis and Treatment Scheme of Inverted Arch Heave for High Speed Railway Tunnel

In recent years,damage cases of inverted arch heave occur frequently,which affect the tunnel operation and traffic safety.Combined with the geological situation,the causes of inverted arch heave of a high speed railway tunnel in Yunnan-Guizhou Plateau were analyzed,and the main factors causing the track uplift were determined to be the effect of high ground stress and the weakening of tunnel bottom surrounding rock under the action of underground water and train dynamic loads.The scheme of demolishing tunnel inverted arch and deepening 1.5 m reconstruction was adopted to carry out comprehensive treatment.MIDAS GTS/NX was used for numerical simulation analysis of the original design and the treatment design scheme.It was verified that the thickening and deepening scheme of the inverted arch could reduce vault subsidence,inverted arch heave and stress,and it meets the requirements.The monitoring scheme of tunnel and track under different operation conditions during construction was developed to ensure safe operation during construction.