Please rephrase the following sentence for clarity according to the style of SCI journalsWhen a fire occurs in an immersed tunnel during the heating stage the thermal expansion of the inner surface wi

In an immersed tunnel, a fire can cause the inner surface to expand thermally during the heating stage. This expansion can lead to the outer surface concrete being pulled and cracked, with the cracks rapidly deepening. Such cracking can cause seawater leakage and jeopardize the safety of the tunnel. Even without through cracks, concrete cracking can expose rebars to marine chloride environments, leading to accelerated corrosion and reduced service life. Thus, the design of fire resistance for immersed tunnels should account for concrete cracking caused by thermal strain