Research conclusions:(1)The reason for the failure of the fire door is that the door is pressed by wind in the tunnel for a long time，so the door is broken more easily in the long tunnel．(2) The fire door＇s renitency must be resistant to the wind pressure of 3.5 kPa．(3) The fire door＇s frame and inner structure must be antisepticized by galvanization．(4) The heavy duty door closer and hinge should be used to the fire door．(5) The fire door＇s frame must be installed in concrete structure and the parts for installation of the door frame should be installed in the concrete structure in advance to reduce the connection by the screw and bolt．(6) The management and maintenance should be strengthened to the door in service．