JP2007046268A - Protective mechanism for antiterrorism measure in cable for existing bridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective mechanism for antiterrorism measures in a cable for an existing bridge, which facilitates work for mounting a protective member, excellent in heat resistance/impact resistance, in the critical location of the cable for the existing bridge. <P>SOLUTION: The protective mechanism A for the antiterrorism measures is installed in the proper location of the cable 5 for a suspension bridge 1 as a huge bridge, or a cable stayed bridge 7. The protective mechanism A comprises a protective board 6 which is externally inserted to the outer peripheral surface of the cable 5 in such a manner that a gap is made in between, and a filler 9 which is infilled into the gap. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a terrorism protection mechanism for existing bridge cables. Specifically, the main cable of the suspension bridge of the long bridge and the cable stayed bridge is related to the protection mechanism from bomb terrorism.

  Conventionally, cables for bridges such as suspension bridges and cable-stayed bridges of long-span bridges are always exposed to salt damage and wind and rain, so it is necessary to cover them with a protective film having excellent weather resistance and corrosion resistance. For example, there is a bridge cable as shown in FIG. This bridge cable is an inner layer plate in which a holding edge member 104 made of titanium angle is attached to the entire periphery of a heat insulating plate 103 made of a foamed polyethylene molded body on the outer periphery of a cable body 102 formed by bundling a large number of strands 101. 105 and a composite covering plate 107 having a skin plate 106 made of a thin titanium plate (see Patent Document 1).

JP-A-6-33421 (Abstract, Fig. 1)

  The cable for bridges described above has a weatherproof and waterproof coating on the surface layer for a long period of time without depending on paint application that requires periodic re-application, by carrying a weatherproof and waterproof function on a skin plate with excellent corrosion resistance. Can be maintained.

  However, for example, when an explosive is applied to a cable for a bridge due to terrorism, the protective film as described above cannot withstand the impact force at the time of the explosion, and some steel wires are cut, so that Next, when another steel wire breaks and the cable for the bridge breaks, there is a possibility that the bridge girder supported collapses and becomes a catastrophe.

  Therefore, in countries that are threatened by terrorism, the current situation is that terrorist acts by intruders are prevented by patrols around the clock, and all suspension bridges, etc., due to the large number of guards and expenses. Security is not possible, and there is a risk that the function as an important highway will not be performed.

  For example, when a tank truck equipped with a combustible material passing through a bridge explodes in an accident, there is a risk that adjacent bridge cables will break due to the high temperature caused by the explosion.

  As countermeasures against such terrorism and accidents, it is necessary to secure the scaffolding etc. to cover the entire length of the existing bridge cable with a new protective member with excellent heat resistance and impact resistance, transportation and There is a problem that the installation work becomes very complicated.

  The present invention was devised in view of the above points, and it is very easy to attach a protective member having excellent heat resistance and impact resistance to a dangerous part of an existing bridge cable. The purpose is to provide a protection mechanism against terrorism in existing bridge cables.

  In order to achieve the above object, the terrorism protection mechanism in the existing bridge cable according to the present invention is a terrorism protection mechanism installed at an appropriate location on a suspension bridge, which is a long bridge, or a bridge cable in a cable-stayed bridge. In the mechanism, it is composed of a protective plate that is extrapolated with a gap provided on the outer peripheral surface of the bridge cable, and a filler that fills the gap.

  Here, by providing a gap with respect to the outer peripheral surface of the bridge cable at an appropriate location of the bridge cable where the blasting material is likely to be installed, extrapolating a protective plate, and filling the gap with a filler such as mortar cement The protective plate blocks direct impact and high heat from blasting to eliminate the influence on the filler, and the filler eliminates indirect impact and high heat on the bridge cable 5 to prevent breakage. is there.

  In the protection mechanism for anti-terrorism in the existing bridge cable according to the present invention, the existing cable provided with the corrosion-resistant protective film is extrapolated by a cylinder formed of a material having excellent heat resistance and impact resistance. It becomes possible to easily cover the protective material by filling the gap between the cable and the cylinder with mortar.

  Also, when constructing the protective mechanism, extra work is completed by injecting a lightweight cylinder to the place where the main cable needs to be protected, and injecting mortar. And construction in a short period of time becomes possible.

Hereinafter, embodiments of the present invention will be described with reference to the drawings to provide an understanding of the present invention.
FIG. 1 is a side explanatory view showing an outline of an example of a suspension bridge among long bridges, and FIG. 2 is a side explanatory view showing an outline of an example of a cable stayed bridge among long bridges.

  The suspension bridge 1 shown here has abutments 2 and 2 on the opposite shore across the strait and river, and the piers 3 and 3 are erected in a state where a sufficient width is secured between each abutment 2 and 2 Is done.

  Therefore, a bridge girder 4 extending between the abutments 2 and 2 is stretched from the abutment 2 through the upper end of the pier 3 and a bridge cable 5 is stretched, and the bridge girder 5 and the bridge girder 4 are connected by the auxiliary cable 10. Is suspended horizontally.

  The cable stayed bridge 7 has several bridge piers 3 standing between relatively long straits and rivers, and the bridge girder 4 extending between these piers 3 is centered on the top of each pier 3. The bridge girder 4 is suspended horizontally by connecting the bridge girder 4 with the bridge cable 5 derived therefrom.

  Therefore, since the bridge girder 4 of the suspension bridge 1 and the cable stayed bridge 7 is suspended and supported by the cable 5 for the bridge, the bridge cable 5 was blown up by the act of terrorism and suffered great damage such as cutting. In some cases, the bridge girder 4 cannot be supported horizontally, and there is a risk of catastrophe such as tilting or collapsing.

  Therefore, in the case of the suspension bridge 1, there is a high risk of explosives being installed at the connection point with the abutment 2 and the bridge cable 5 located near the center of the bridge girder 4.

  Further, in the case of the cable-stayed bridge 7, there is a high risk that explosives are installed at the connection point with the bridge cable 5 on the bridge girder 4.

  Thus, as shown in FIGS. 3 (a) and 3 (b), a terrorism protection mechanism is provided for the bridge cable 5 at a high risk location where explosives are installed.

  This anti-terrorism protection mechanism A is a state in which both ends of semi-cylindrical protection plates 6 and 6 excellent in impact resistance, fire resistance and durability are overlapped on the outer peripheral surface in the longitudinal direction of the cable 5 for bridges. In this case, it is extrapolated with a certain clearance from the outer peripheral surface of the bridge cable 5 by being coupled by the joining pins 11.

  The mortar cement injection hose 8 is inserted into the gap between the outer peripheral surface of the cable 5 for the bridge and the protective plate 6, and the mortar cement 9 is injected by closing one end of the protective plate 6 so that the mortar can be obtained without gaps. The cement 9 can be filled.

  As a result, the outer peripheral surface of the bridge cable 5 is encapsulated by the mortar cement 9, and the impact force on the bridge cable 5 due to the explosion is reduced.

  In addition, as a material of the said protective plate 6, although what has impact resistance, fire resistance, and durability is used, the polyethylene system which was most excellent in fire resistance in it, and was most excellent in impact resistance It is desirable to use the most suitable material according to the environment such as nylon or epoxy having the most durability.

  In addition, it is not always necessary to fill mortar cement between the outer peripheral surface of the bridge cable 5 and the protective plate 6. For example, cement milk mixed with hardener or hardened resin filler absorbs impact caused by explosion. Any filler may be used as long as it can prevent breakage of the bridge cable, such as a material to be used and a material having excellent fire resistance.

  In the present invention, in the case of the suspension bridge 1 as shown in FIG. 4, a terrorism protection mechanism A having a length of about 2 meters is provided at the connecting portion between the abutment 2 and the bridge cable 5, and further, in the vicinity of the center of the bridge girder 4. Is provided with a protection mechanism A for terrorism countermeasures.

  Further, as shown in FIG. 5, in the case of the cable-stayed bridge 7, a terrorism protection mechanism A is provided at each connection point with the bridge cable 5 on the bridge girder 4.

  By providing the protection mechanism A for terrorism countermeasures at the location of the bridge cable 5 where the blasting material is easily installed in this way, for example, when the blasting material is attached and blown up by terrorism or a tank truck equipped with a combustible material At the time of an explosion flame due to an accident, the outer peripheral surface of the bridge cable 5 is encapsulated by a mortar cement 9 and a protective plate 6 having a certain thickness, so that the protective plate 6 is first subjected to direct impact and high heat due to blasting. By blocking, the influence on the mortar cement 9 is eliminated, and the mortar cement 9 eliminates indirect impact and high heat on the bridge cable 5 to prevent breakage.

  Further, when removing the protection mechanism A for countermeasures against terrorism, the protective plate 6 can be easily removed by removing the protective plate 6 and then crushing the exposed mortar cement 9 with a hammer or the like.

It is side explanatory drawing which shows the outline | summary of an example of a suspension bridge among long-span bridges. It is side explanatory drawing which shows the outline | summary of an example of a cable-stayed bridge among long-span bridges. It is explanatory drawing which shows an example of the protection mechanism for terrorism countermeasures to which this invention is applied. It is explanatory drawing which shows an example at the time of attaching the protection mechanism for terrorism countermeasures to which this invention is applied to a suspension bridge. It is explanatory drawing which shows an example at the time of attaching the protection mechanism for terrorism countermeasures to which this invention is applied to a cable-stayed bridge. It is explanatory drawing which shows an example of the conventional cable for bridges.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Suspension bridge 2 Abutment 3 Bridge pier 4 Bridge girder 5 Cable for bridge 6 Guard plate 7 Cable-stayed bridge 8 Mortar cement injection hose 9 Mortar cement 10 Auxiliary cable 11 Pin for connection

Claims (3)

In the protection mechanism for anti-terrorism that is installed at the appropriate place of the cable for bridges of suspension bridges or cable-stayed bridges that are long bridges,
A protective plate that is extrapolated with a gap to the outer peripheral surface of the bridge cable;
A protective mechanism for countering terrorism in an existing bridge cable, comprising: a filler that fills the gap. The protection mechanism for terrorism countermeasures in an existing bridge cable according to claim 1, wherein the protection plate is made of a synthetic resin material having impact resistance, fire resistance and durability. The protective mechanism for terrorism countermeasures in an existing bridge cable according to claim 1, wherein the filler is formed of mortar cement.

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