Study on anti-fire panel for vehicle fire in immersed tunnel

Composite members made of steel and concrete are adopted for immersed tunnel. Since steel plates are exposed to the internal side of the road, vehicle fire countermeasures in tunnels are required. Investigation about the temperature rise at the composite member was made for test specimen with a ceramic anti-fire board. For the design temperature curve by the vehicle fires, the fire tests were carried out in a heating furnace. It is explained that the temperature rise in the composite members covered by the anti-fire board was within the allowable temperature, accompanied with a exfoliation phenomenon of the steel plates, spotty temperature rise on the joint portions, etc. On the other hand, the heat transfer analysis with which existence of the moisture in the concrete and separation of the steel plates from concrete can well explain the phenomenon in the fire test.