Abstract There are no available guidelines or methodologies to design the concrete lining in a tunnel for loss of functionality following a fire event. Historical tunnel fires confirm that tunnel downtime following an extreme event can lead to major economic losses, while fire protection design of the concrete lining can be adjusted to minimize losses. This paper provides a framework to characterize fire damage in a tunnel structure, where spatial and temporal distributions of fire temperature within a tunnel structure are modeled, and statistics of the potential damaged volume of the concrete lining that would require repair are quantified. A simplified spalling model, considering an initiation time, rate of spalling, and finishing time, is incorporated within the analysis to provide a more realistic measure of the damage. The results show that incorporation of spalling makes a significant difference in the damage assessment. Structural stability of the tunnel is checked under an extreme fire scenario to verify that, while experiencing extensive damage, the structure does not collapse. This paper focuses on a passenger railway tunnel, and is a first step in establishing a risk-based framework to guide fire protection design of a tunnel lining. The proposed approach can be applied to other tunnel types.

中文翻译：

---

表征隧道火灾期间混凝土衬砌的损坏

摘要 没有可用的指导方针或方法来设计隧道中的混凝土衬砌以防止火灾事件后功能丧失。历史隧道火灾证实，极端事件后隧道停机会导致重大经济损失，而混凝土衬砌的防火设计可以调整，以最大限度地减少损失。本文提供了一个表征隧道结构火灾损坏的框架，其中对隧道结构内火灾温度的空间和时间分布进行了建模，并对需要修复的混凝土衬砌潜在损坏体积的统计数据进行了量化。考虑到起始时间、剥落速率和完成时间的简化剥落模型被纳入分析，以提供更现实的损坏测量。结果表明，剥落的加入对损伤评估有显着影响。在极端火灾情况下检查隧道的结构稳定性，以验证在遭受严重损坏时，结构不会倒塌。本文以客运铁路隧道为重点，是建立基于风险的框架以指导隧道衬砌防火设计的第一步。所提出的方法可以应用于其他隧道类型。这是建立基于风险的框架以指导隧道衬砌防火设计的第一步。所提出的方法可以应用于其他隧道类型。这是建立基于风险的框架以指导隧道衬砌防火设计的第一步。所提出的方法可以应用于其他隧道类型。