To study single-tunnel fires in concrete immersed tunnels, a fire test was carried out on a concrete immersed tunnel with a longitudinal length of 5.8 m and a large scale of 1:5. Through self-developed heating and cooling systems and an external load provided by a self-balancing reaction frame, we investigated the temperature distribution, spalling degree, crack distribution, deformation performance, and acoustic emission features of the model. The results showed that both the deformation and cracking of the tunnel exposed to the fire exerted an influence on the unexposed tunnel. Impacted by the single-tunnel fire, the cracks in the immersed tunnel were composed of mainly circumferential and longitudinal cracks, the former of which were connected to each other in places without stirrups. Based on an analysis of the basic AE parameters and the results obtained by a three-dimensional scanner, the spalling of the concrete was caused by different mechanisms, and the maximum spalling depth was 110 mm.

为研究混凝土沉管隧道中的单隧道火灾，在纵向长度为5.8 m，大比例为1:5的混凝土沉管隧道上进行了火灾试验。通过自主开发的加热冷却系统和自平衡反力架提供的外部载荷，我们研究了模型的温度分布、剥落程度、裂纹分布、变形性能和声发射特性。结果表明，暴露于火灾的隧道的变形和开裂都对未暴露的隧道产生了影响。受单隧道火灾影响，沉管隧道裂缝主要由环向裂缝和纵向裂缝组成，环向裂缝和纵向裂缝在没有箍筋的地方相互连接。