NUMERICAL INVESTIGATION OF RC TUNNEL SEGMENTS SUBJECTED TO ELEVATED TEMPERATURE VIA FEM

Abstract

There has been increasing concern about the fire-resistant design of reinforced concrete tunnel lines among structural engineers due to the fire incidents that occurred recently. A limited number of experimental works focused on the fire behavior of the conventional reinforced concrete (RC) and hybrid fiber reinforced concrete (HFRC) tunnel segments have been presented in the literature. However, there is no comprehensive numerical study related to RC shield tunnel segments under the effect of elevated temperature. Thus, this study intends to establish a 3D finite element model (FEM) for the evaluation of the fire behavior of RC shield tunnel segments. At the first stage of the presented FEM, the temperature distribution that occurred in the RC tunnel segment was evaluated with a heat transfer analysis carried out. In the second stage, the stress analysis was conducted to calculate the load-displacement behavior of the RC tunnel segment under the combined effect of the gravity load and the elevated temperature. The results obtained from the FEM were compared with an experimental work existing in the literature. The fact that numerical analysis is compatible with experimental results proves that the presented FEM can be used in the determination of the behavior of RC shield tunnel segments subjected to elevated temperature.