JP2000192797A - Protector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protector which secures the safety of operation space with reliability similar or superior to that provided by structures of the prior art although the protector does not have a horizontal brace piece nor a column near its center. SOLUTION: A cushioning material layer 13 is provided on the roof 12 of a protector 1 in such a way as to have a certain thickness. The kinetic energy of an object falling from the top of a tunnel is absorbed by the cushioning material layer 13 and the distance over which the object falls before colliding against the protector 1, i.e., the kinetic energy of the falling object, is smaller than before. Therefore, although the protector does not have a column 11 near its center and no horizontal brace piece is used at the connection between the column 11 and the roof 20, the protector can secure the safety of operation space with reliability similar or superior to that provided by structures of the prior art.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protector for ensuring the safety of a work space in an underground cavity, and more particularly to a protector having a simplified structure.

[0002]

2. Description of the Related Art When performing work in an underground cavity such as a tunnel, it is necessary to install a protector for preventing falling objects from the upper part of the underground cavity.

[0003] Here, a conventional protector 100 is shown.
Will be described with reference to the schematic sectional view of FIG. The protector 100 is, for example, a protector for ensuring the safety of a work space in the tunnel 2. The protector 100 includes three pillars 111 a erected on the floor 3 of the tunnel 2 at regular intervals and three pillars.
A main part 111 which is constituted by a roof 111b which is supported by 11a and prevents falling objects from the upper wall of the tunnel 2 and which constitutes a work space; and a worker passage 112 which is constituted by a plurality of columns and a roof . Each component of the protector 100 includes:
Usually made of steel. Here, the support 111a and the roof 111
The connection portion with b is reinforced by fire receiving pieces 113, 113, and has a structure that can withstand a greater impact. In addition, by disposing the column 111a near the center, a structure that can withstand a larger load, that is, a more secure structure is obtained.

[0004]

However, in the protector 100, the support 11 is also provided near the center of the work space.
Since a plurality of 1a were arranged in a row, the width W of the work space was narrow as shown in FIG. Further, the width W was further reduced because the fire receiving piece 113 was provided. For this reason, in the working space, it may be difficult to achieve the legal standard that the width W must have a value equal to or higher than a certain ratio with respect to the height h. Further, when the protector 100 is used to repair an existing tunnel, the protector 100 must pass an emergency vehicle, but the support 111a is located near the center of the work space.
In some cases, it is difficult for the emergency vehicle to pass through the inside of the protector 100 during emergency travel.

In view of the above circumstances, the present invention provides a protector that ensures the safety of a work space with the same or higher reliability as that of the conventional structure despite having no fire catching piece or a column near the center. The purpose is to do.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 is fixed on a floor of an underground cavity,
A protector comprising an upright supporting column, and a roof supported by the supporting column to prevent a fallen object from the upper part of the underground cavity, wherein a protector for securing the safety of a work space in the underground cavity is provided. A cushioning material layer for buffering a falling impact of a falling object is provided thereon.

According to the first aspect of the present invention, since the cushioning layer is provided on the roof to buffer the falling impact of the falling object, the kinetic energy of the falling object from the upper part of the tunnel is controlled by the cushioning layer. Absorbed. Further, the distance over which the falling object falls before colliding with the protector, that is, the kinetic energy of the falling object is smaller than in the conventional case.
Therefore, the safety of the work space can be ensured with greater reliability than before. Further, the safety of the work space can be ensured with the same level of reliability as before, without using a laterally extending reinforcing member such as a fire receiving piece for the fixing portion.

Further, even if the support is arranged only at both ends of the roof, the safety of the work space can be ensured with the same level of reliability as in the prior art. Becomes possible. According to the second aspect of the present invention, since the number of columns required is smaller than that of the related art because the column is not provided near the center, the production cost of the protector is significantly reduced as compared with the conventional example. There is also an effect that.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a protector 1 according to one embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view illustrating the entire protector 1. FIG. 2 is a schematic side view of the protector 1 viewed from the X direction in FIG. FIG. 3 is a schematic side view of the worker passage 20 which is a part of the protector 1.

First, the configuration will be described. As shown in FIG. 1, the protector 1 is schematically constituted by a main part 10 for ensuring the safety of a work space and a worker passage 20 for allowing a worker to pass.

As shown in FIG. 1, the main portion 10 is provided with two columns arranged at regular intervals on a concrete layer 11a provided on a floor 3 of a tunnel 2 through a girder 11b. 11, a roof 12 supported by the pillar 11 to prevent falling objects from the upper wall of the tunnel 2, and a cushioning material layer 13 provided on substantially the entire surface of the roof 12. Here, the pillars 11 are provided at both ends of the roof 12,
The position of the support 11 in one row is the same as that of the support 11 in the other row.
To the position.

The columns 11 are steel columns, and the upper and lower portions of the columns 11 arranged in the same row are connected to the adjacent columns 11 by connecting steel plates 11c. In order to improve the rigidity of the protector 1, one end of the reinforcing rod 11d is fixed to the support 11, and the other end of the reinforcing rod 11d is fixed to the adjacent support 11. Here, as shown in FIG.
When two reinforcing rods 11d are provided between the columns 11 so as to intersect each other, the rigidity of the protector 1 is further improved.

The roof 12 has columns 11
A well-known cross beam 12a arranged and fixed on
The adjacent cross beams 12a, 12a are fixed to each other and the roof 12
It is generally constituted by a well-known vertical girder 12b for improving the rigidity and a well-known lining plate 12c laid on the horizontal girder 12a.

The cushioning material layer 13 is made of a light-weight and shock-absorbing material, for example, EPS (Styrofoam). The cushioning layer 13 absorbs the impact of a fallen object from the upper part of the tunnel 2 and reduces the distance between the upper part of the tunnel 2 and the protector 1. The kinetic energy of the falling object from the upper part of the tunnel 2 is reduced by shortening the length. That is, the kinetic energy of the falling object from the upper part of the tunnel 2 can be adjusted by the thickness of the buffer material layer 13.

[0015] As shown in FIG.
A floor plate 21 and a main girder 22 having one side fixed to the support 11 of the main part 10, and a column 23 connecting the other end of the floor plate 21 and the other end of the main girder 22. Pillar 23
As shown schematically in FIG. 3, the upper and lower parts are joined steel thick plates 2
It is connected to the adjacent column 23 by 3a. further,
One end of the reinforcing bar 23b is fixed to the column 23, and the other end of the reinforcing bar 23b is fixed to the adjacent column 23. Here, two reinforcing bars 23b are provided between the columns 23 so as to cross each other.

Next, a case where an object falls from the upper part of the tunnel 2 to the protector 1 will be considered. The falling object is the cushioning material layer 1.
3 received. At this time, the kinetic energy of the falling object is absorbed by the cushioning material layer 13, so that the load applied to the column 11 is smaller than in the conventional case. further,
Since the cushioning material layer 13 has a certain thickness, the distance over which the fallen object falls before colliding with the protector 1, that is, the kinetic energy of the fallen object becomes smaller than in the past.
Therefore, the load applied to the column 11 is further reduced as compared with the related art. For this reason, the protector 1 does not have the strut 11 near the center portion, and has a reliability equal to or higher than that of the related art despite the fact that the fire receiving piece is not provided at the connection between the strut 11 and the roof 20. To ensure the safety of the work space.

As described above, according to the protector 1 of the embodiment of the present invention, the cushioning material layer 13 is provided on the roof 12 so as to have a certain thickness. Is absorbed by the cushioning material layer 13, and the distance over which the falling object falls before colliding with the protector 1, that is, the kinetic energy of the falling object becomes smaller than in the conventional case. Therefore, the pillar 11 is located near the center.
In addition, the safety of the work space can be ensured with the same or higher reliability as in the related art, even though there is no fire receiving piece at the connection between the support 11 and the roof 20. Therefore, the emergency vehicle can safely pass under the protector 1 in emergency traveling. This effect is particularly remarkable in a tunnel having a small cross section. In addition, since there is no support 11 near the center, the number of support pillars required is smaller than before, and since no fire receiving piece is used, the production cost of the protector 1 is significantly reduced as compared with the conventional example. Is done.

The present invention is not limited to the present embodiment, but can be arbitrarily modified without departing from the spirit of the present invention. For example, the cushioning material layer 13 is not limited to the EPS, and a cushioning material made of paper, for example, can be applied.

[0019]

According to the first aspect of the present invention, since the cushioning layer is provided on the roof to buffer the falling impact of the falling object, the kinetic energy of the falling object from the upper part of the tunnel is reduced by the cushioning layer. And the kinetic energy of the falling object is smaller than before, so that the safety of the work space can be secured with greater reliability than before.

According to the second aspect of the present invention, it is possible to ensure the safety of the work space with the same level of reliability as before, and to significantly reduce the production cost of the protector as compared with the conventional method. Is done.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating the entire protector 1. FIG.

FIG. 2 is a schematic side view of the protector 1 viewed from an X direction in FIG.

FIG. 3 shows a worker passageway 20 which is a part of the protector 1.
FIG.

FIG. 4 is a schematic cross-sectional view of a protector 100 as a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Protector 2 Tunnel 3 Floor 10 Main part 11 Prop 12 Roof 13 Buffer material layer 20 Passage for workers

Claims (2)

[Claims] 1. An underground cavity, comprising: a column fixed and erected on the floor of an underground cavity; and a roof supported by the column to prevent falling objects from an upper portion of the underground cavity. A protector for ensuring the safety of a work space in the inside, wherein a cushioning material layer is provided on the roof for buffering a falling impact of a falling object. 2. The protector according to claim 1, wherein the columns are disposed only at both ends of the roof.