JP2002360722A - Fireproof protection method for electric and communication cables and the like within tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a direct protection of electric and communication cables and the like installed utilizing internal walls of tunnels with a protective box from tunnel fires while checking a temperature rise in the protection box. SOLUTION: The equipment installed utilizing an internal wall of a tunnel is enclosed with the fireproof board-structured protective box 1 to be cut off from a tunnel space and heat propagated into the protective box 1 when a fire occurs due to car accidents or the like within the tunnel is made to escape to the side of a concrete body c of the tunnel through a metal plate 8 which is arranged on the internal surface side of the protective box 1 contacting the concrete body c thereby checking temperature rises in the protective box 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the protection of equipment such as electric and communication cables and emergency water pipes provided along the inner wall of a tunnel from fire in the tunnel, and to the fire resistance of electric and communication cables in the tunnel. Regarding protection methods.

[0002]

2. Description of the Related Art In recent years,
In large cities, road tunnels are being developed as part of measures to alleviate traffic congestion. On the other hand, when an automobile fire occurs as an accident in a road tunnel, for example, it is known that the temperature reaches a high temperature exceeding 1000 ° C.
There is an increasing need for fireproof protection of various equipment in a tunnel, especially electric and communication cables in which plastic is frequently used as a covering material.

[0003] Against this background, high-temperature fires (10
As a highly adiabatic refractory plate capable of blocking heat caused by a heat-resistant plate (00 ° C.), a protective box having a composite structure of a ceramic refractory plate and rock wool (a refractory plate structure) has been developed. For example, a method is known in which a protective box surrounds an electric / communication cable laid on a ceiling or a side wall of a road tunnel and shields the cable from heat caused by a high-temperature fire in the tunnel.

[0004] However, even if the inside of the protective box in which the cables are laid is heated by the heat of a fire and there is a possibility that the cables may be seriously affected, there is no place to release the heat due to the heating, and the cables are placed inside the tunnel. In order to completely protect against fire, measures to dissipate heat inside the protection box are important issues. On the other hand, in order to protect the concrete skeleton side (wall surface) of the tunnel from fire, attach a fire-resistant plate with a thickness of about 25 mm to the tunnel wall and release heat from the fire-resistant plate to the concrete skeleton or the stratum side in contact with the back side. It has been known.

The present inventor has arrived at the present invention based on the finding that a fire-resistant plate is frequently used for protecting the wall surface of a tunnel against a fire in the tunnel, together with the research on the above-mentioned problems. That is, the object of the present invention is to contact a metal plate having good thermal conductivity provided on the inner surface side of the protective box with the concrete skeleton of the tunnel, and at the same time, to use a large number of anchor bolts driven in to attach the metal plate. It is an object of the present invention to provide a fireproof method for protecting electric / communication cables and the like in a tunnel, in which heat in a protection box can be efficiently released to a concrete skeleton side and a rapid rise in temperature in the protection box can be suppressed.

[0006]

In order to achieve the above object, a fire protection method for an electric / communication cable or the like in a tunnel, which is a feature of the present invention, is a method for protecting a facility provided using an inner wall of a tunnel from fire. It is enclosed by a protective box with a plate structure and is shielded from the tunnel space, and the heat that has propagated into the protective box in the event of a fire due to a vehicle accident or the like in the tunnel is provided on the inner surface side of the protective box. Through the metal plate that comes into contact with the concrete body.

In this configuration, the fire-resistant plate structure is
Considering the durability and the ability to suppress the thickness of the box itself, a composite structure of a ceramic refractory plate and rock wool as a heat insulating material is preferable. On the other hand, aluminum, steel plate, copper plate, or the like having good thermal conductivity is used for the metal plate, and a heat insulating material is adhered to the inside to prevent heat transfer from the metal plate into the protection box. Further, it is preferable that the metal plate is provided in the protective box by using anchor bolts driven into the concrete skeleton of the tunnel so as to promote heat radiation to the concrete skeleton side.

[0008]

Embodiments of the present invention will be described below. First, a description will be given of an example in which the equipment is an electric / communication cable with reference to FIG. 1 regarding a fireproof protection configuration of a tunnel inner wall equipment in which the method of the present invention is implemented. 2, a ceramic-based refractory plate 3, 4 and a heat insulating material 5 such as rock wool are sequentially superposed. The protective box 1 is fixed to the inner wall of the tunnel (concrete skeleton c) by anchor bolts 7 at both sleeve portions (indicated by reference numeral 6) of the steel plate 2 and the refractory plates 3 and 4 excluding the rock wool 5. I have.

Reference numeral 8 denotes a metal plate having a shape corresponding to the protection box 1 and having good heat conductivity, which is provided between the refractory plate 4 and the heat insulating material 5 so as to face the protection box 1. The metal plate 8 is fixed to an inner wall (a ceiling or a side wall) of the tunnel by an anchor bolt 9 driven into a concrete skeleton c at a top plate portion 8a which apparently forms the upper surface of the protection box 1.

A heat insulating material 5a similar to the heat insulating material 5 is attached to the inside of the top plate 8a of the metal plate 8 fixed by the anchor bolt 9. The protection box 1 accommodates a laying pipe 11 of an electric / communication cable, 12 is a support plate thereof, and 13 is a U bolt used to support the laying pipe 11. The illustrated refractory plates 3 and 4 may be implemented by a single refractory plate in some cases.

Next, the method of the present invention will be described. An electric / communication cable or the like provided using the inner wall of the tunnel is surrounded by a protection box 1 having a fire-resistant plate structure and is shielded from the tunnel space. The heat transmitted by the tunnel fire and transmitted into the protection box 1 is provided so as to be adhered to the inner surface side of the protection box 1.
Through the metal plate 8 (and a large number of anchor bolts 9) brought into contact with the side, it escapes to the concrete skeleton c side to suppress a rapid rise in temperature inside the protection box 1 and to connect facilities such as electric and communication cables inside the tunnel. The method according to the invention is carried out in such a way that it can be protected from fire.

[Brief description of the drawings]

FIG. 1 is a front cross-sectional view showing one embodiment of a fireproof protection structure for an electric / communication cable or the like in a tunnel in which a method of the present invention is implemented.

[Explanation of symbols]

 1 is a protective box 2 is a steel plate (surface material) 3, 4 is a fireproof plate 5, 5a is a heat insulating material 8 is a metal plate 8a is a top plate portion 9 is an anchor bolt c is a concrete frame

Claims (2)

[Claims] 1. A facility provided by using an inner wall of a tunnel, which is surrounded by a protection box having a fire-resistant plate structure and is shielded from a tunnel space, and heat transmitted to the protection box in the event of a fire due to a vehicle accident or the like in the tunnel. Through a metal plate provided on the inner surface side of the protection box and in contact with the concrete skeleton side of the tunnel, to escape to the concrete skeleton side. 2. The metal plate is fixed to the concrete skeleton by anchor bolts driven into the concrete skeleton, and a heat insulating material is adhered to the inside of the metal plate. The method for protecting fire and electricity from electric and communication cables in a tunnel according to claim 1, wherein heat is prevented from being transmitted.