Tunnel portal heat preservation device

The embodiment of the utility model provides a tunnel portal heat preservation device which comprises a fixing assembly, a supporting assembly and a heat preservation assembly, and the fixing assembly extends outwards from an arch foot part of a tunnel; the supporting assembly is of an arch structure, the two ends of the supporting assembly are fixed to the fixing assemblies respectively, the supporting assembly extends outwards from the supporting frame of the hole, and the shape of the outer surface of the supporting assembly is matched with the shape of the inner surface of the tunnel inner cavity; the heat preservation assembly is arranged on the outer surface of the supporting assembly which is used for supporting the heat preservation assembly. Through the arrangement, the heat preservation device not only has a heat preservation effect, but also can be used as a construction frame, and waste of manpower and material resources is reduced. 本申请实施例提供一种隧道的洞口保温装置，包括固定组件、支撑组件和保温组件，固定组件由隧道的拱脚部向外延伸；支撑组件呈拱形结构，支撑