Lining damage is a crucial issue affecting the operation mountain tunnels, as it diminishes the bearing capacity and shortens the service life of tunnels. Investigation and treatment of lining damage are essential for enhancing the safety and prolonging the service life of tunnels. This paper presents a case study on the characteristics and treatment measures of the lining damage of a mountain tunnel by field investigation, numerical simulation and in-situ monitoring. To better understand the operational status of the tunnel structures subject to lining damage, water leakages, cracks and voids behind the lining are detected to obtain the distribution and morphological characteristics of lining damage. Detection results show that voids behind the lining are the main cause of lining cracking, and thus, the mechanical performance and failure mechanism of lining structures with voids are evaluated by numerical simulation. Based on the results, treatment measures of lining damage are adopted, including crack grouting, shotcrete support, and reconstruction of the secondary lining. Finally, the effectiveness of treatment measures is investigated by analyzing field monitoring data. Lessons learned from this case study are discussed, thus providing a reference for the treatment of lining damage in other tunnels.

衬砌损坏是影响山地隧道运营的重要问题，它降低了隧道的承载力，缩短了隧道的使用寿命。衬砌损伤的调查和处理对于提高隧道的安全性和延长隧道的使用寿命至关重要。本文介绍的特性，并通过现场调查，数值模拟和山隧道衬砌损伤的治疗措施的案例研究中-原位监测。为了更好地了解受衬砌破坏的隧道结构的运行状况，检测衬砌背后的漏水、裂缝和空隙，以获得衬砌破坏的分布和形态特征。检测结果表明，衬砌背后的空隙是衬砌开裂的主要原因，因此，通过数值模拟评估了衬砌结构的力学性能和失效机理。根据分析结果，采取裂缝灌浆、喷射混凝土支护、二次衬砌改造等措施对衬砌破损进行处理。最后，通过分析现场监测数据，考察处理措施的有效性。讨论了从这个案例研究中吸取的教训，