Please translate the following sentence into English according to the style of SCI journals升温阶段火灾导致隧道内部混凝土受热膨胀隧道外部混凝土受拉开裂；降温阶段隧道内表面因降温开裂。在这种内外交替开裂的模式下沉管隧道容易形成贯穿裂缝。

During the heating phase, the concrete inside the tunnel expands due to the fire, while the concrete outside the tunnel experiences tensile cracking. During the cooling phase, the inner surface of the tunnel cracks due to the temperature decrease. In this alternating pattern of internal and external cracking, immersed tube tunnels are prone to developing through cracks.