Experiment on single-tunnel fire in concrete immersed tunnels. (October 2021)

• Record Type: Journal Article
• Authors: Lin, Jianqing; Dong, Yuli; Duan, Jintao; Zhang, Dashan; Zheng, Wei
• Is Part Of: Tunnelling and underground space technology. Volume 116(2021)
• Publication Date: 2021-10
• Subjects: Immersed tunnel -- Fire events -- Crack mode -- Spalling -- Acoustic emission; HZMB Hong Kong-Zhuhai-Macao Bridge -- IMP Isolated Measurement Pod -- LVDT linear variable differential transformer -- AE Acoustic Emission; Tunneling -- Periodicals; Underground construction -- Periodicals; Tunnels -- Periodicals; Underground areas -- Periodicals; 624.193
• DOI: 10.1016/j.tust.2021.104059
• Languages: English
• ISSNs: 0886-7798

Abstract

Highlights: Single-tube test of concrete immersed tunnel subjected to applied loading and fire. Concrete spalling due to the different mechanisms. Concrete crack patterns depend on the distribution of reinforcements. Abstract: 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.