隧道火灾与衬砌辐射对流协同传热作用机制及衬砌爆裂损伤演化机理研究

隧道火灾因燃烧时间长、火灾规模大等特点，导致衬砌结构损伤特别严重，甚至出现坍塌。火灾与衬砌结构间的高强度辐射和对流传热是引起衬砌混凝土爆裂和结构安全性急剧下降的直接原因。因此引起了全世界隧道领域科研人员的高度关注。.本项目以火焰-烟-衬砌为研究对象，拟采用理论分析、室内试验和基于辐射对流传热下的衬砌多场耦合数值计算方法相结合的研究手段，对衬砌与隧道火焰辐射和烟气对流协同传热机制、衬砌内部多场耦合特性、衬砌爆裂损伤演化机理和火灾后衬砌安全性评价开展深入研究。基于此揭示火灾下衬砌界面辐射和对流换热分布特征、明确衬砌爆裂的时空响应机制。研究具有非常重要的理论价值和显著的工程应用背景。.通过研究，建立衬砌与火焰辐射和烟气对流协同传热模式和计算方法，探明衬砌内部热-水-汽多场耦合特性，提出衬砌爆裂损伤规律的演化模型，定量评价爆裂损伤后衬砌结构安全性，为隧道衬砌结构防火设计和灾后评估提供科学依据。

The serious damage to lining, even collapse, is usually observed in tunnel fires due to its long burning duration and large scale. The strong radiative and convective heat transfer to the lining are believed to be responsible for the spalling and the significant reduction of structural safety. Therefore, it has attracted much attention from the tunnel society all over the world..This project is focused on the flame-smoke-lining in tunnel fires. Theoretical analysis, model tunnel fire experiment and multi-field coupled numerical simulation in the lining will be employed to study the synergistic mechanism between the lining and the flame radiative and the smoke convective heat transfer, the coupled principle in the lining, the spalling evolution of the concrete and the structural safety. The radiative and convective heat transfer distribution on the lining interface, as well as the spalling spatio-temporal response mechanism of the lining is subsequently revealed. This project is considered to be highly meaningful to theory and application..By this study, it is expected to build up the synergistic heat transfer model and a method between the lining and the flame radiation and the smoke convection, understand the coupled thermo-hydro-vapor principle, propose an evolution model of concrete spalling, as well as evaluate the structural safety after spalling. The conclusion is believed to be quite helpful for the fire protection designing of the lining and its assessment after fire.