JP2006233498A - Bridge-fall prevention equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide bridge-fall prevention equipment which can be surely attached to a lower structure section, without the need for drilling a deep anchor hole by means of core boring, or the risk of cutting a reinforcing bar in the lower structure section. <P>SOLUTION: Prestressing-steel supporting blocks 1 with upper locking parts 4 each also serving as a cross-girder supporting stopper are arranged on both side surfaces of a lower structure 3 made of concrete, in such a manner as to face each other in front and rear positions, and connected together across the front and rear upper locking parts by means of prestressing steel 25 for connection, so as to be fixed to the lower structure 3 made of concrete. Prestressing-steel anchoring blocks 16 with upper locking parts 4 each also serving as a main-girder supporting stopper are arranged on both the side surfaces of the horizontal upper section of the lower structure in an opposed manner so as to be locked to the top surface of the lower structure 3. Traverse prestressing steel 14, which is arranged on the outside of the blocks 1 on both the longitudinal sides in such a manner as to be supported on the blocks 1, is tensioned and anchored to the blocks 16 which are arranged on both horizontal sides. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fall prevention apparatus for preventing an upper structure such as a bridge girder from falling from a lower structure such as a pier or an abutment.

  Conventionally, as a bridge drop prevention device, a plurality of anchor holes with a predetermined depth are drilled in the center of the width direction on an existing abutment or pier, and the anchor bolts are embedded and fixed under the anchor holes. The anchor bolt is inserted into a support wall such as cast concrete or precast concrete block, and the support wall is fixed by a fixing bracket screwed and fixed to the top of the anchor bolt so as to prevent a bridge girder such as a main girder from being dropped. A fallen bridge prevention apparatus is known (for example, see Patent Document 1).

JP 2004-124617 A

  In the conventional case, it is necessary to drill a considerably deep anchor hole in an existing abutment or existing pier. There is a risk of cutting. Also, when installing so as not to cut the reinforcing bars in existing abutments or existing piers, there is a case where the anchor bolt embedding length is insufficient, and it is necessary to compensate for this separately due to strength problems, which makes the construction complicated In some cases, construction changes may be required.

  The present invention eliminates the need for drilling deep anchor holes by core boring, so that there is no shortage of anchor bolt embedding length, and there is no risk of cutting reinforcing bars in the substructure such as existing abutments or piers. An object of the present invention is to provide a falling bridge prevention device that can be attached to a lower structure part.

  In order to solve the above-mentioned problem advantageously, in the falling bridge prevention device according to the first aspect of the present invention, the upper locking portions (4) which also serve as horizontal girder support stoppers on both sides in the front-rear direction of the concrete lower structure (3). The PC steel bearing block 1 having the upper and lower structures is arranged so as to be locked to the upper surface of the concrete lower structure (3), and the upper and lower structures extend over the upper locking portions of the front and rear PC steel bearing blocks (1). Are connected to the concrete substructure by connecting PC steel members (25) arranged in the gap G between them, and the main girder support stoppers are respectively provided on both lateral sides of the concrete substructure (3). The PC steel fixing block (16) having the upper locking part (4) which also serves as a counter is disposed so as to be locked to the upper surface of the concrete lower structure (3). Characterized in that by stressing anchorage to the arranged to support to the outside of the bearing bracket 1 horizontal clamping PC steel member (14) the PC steel fixing blocks arranged on both sides in the lateral direction (16).

  In the second invention, in the fallen bridge prevention device of the first invention, a plurality of PC steel support blocks (1) that oppose the front-rear direction are arranged at intervals in the left-right direction, and the concrete substructure (3) The protrusion length in the front-rear direction is increased as it approaches the center in the left-right direction, and the laterally tightened PC steel material (14) disposed on the outer side of each PC steel support block (1) disposed on both side surfaces in the front-rear direction is substantially flat. It is arranged in an arc shape.

  Further, in the third invention, in the falling bridge prevention device of the first invention or the second invention, the PC steel support block (1) is a precast concrete block (2) fixed to the concrete substructure (3), The steel block is composed of a steel laterally-clamped PC steel support bracket (11) fixed to the concrete block (2) by anchor bolts (31), and each laterally-clamped PC steel material 14 is attached to the PC steel material support bracket (11). It is characterized by being supported.

  In the fourth invention, the PC steel material fixing block 16 is a precast concrete block (17) fixed to the concrete substructure 3 and the concrete block in the fallen bridge prevention device of the first invention or the second invention. (17) is composed of a steel PC steel material fixing bracket (19) fixed by an anchor bolt (34), and each laterally tightened PC steel material 14 is fixed to the PC steel material fixing bracket (19). And

According to the present invention, PC steel support blocks arranged on the front and rear sides of the upper part of the concrete substructure can be connected by the connecting PC steel, and can be attached to the lower structure and laterally tightened PC arranged on the outside thereof. Since the steel material can be fixed to the concrete substructure by pressing it against the concrete substructure, it is not necessary to drill a deep anchor hole by core boring in the concrete substructure. There is no shortage, and there is no risk of cutting reinforcing bars in concrete substructures such as existing abutments or piers. Further, since the lower part of each concrete block only needs to be temporarily fixed to the concrete substructure by a simple temporary fixing means such as an insert, construction is easy.
In addition, the PC steel fixing blocks placed on the left and right sides of the concrete substructure can be used to fix the tension of the horizontal PC steel, and the PC steel fixing block itself can be fixed to the concrete by the PC steel. Can be fixed to objects.

  According to the second invention, the PC steel support block that opposes the front-rear direction is laterally fastened by simply extending the length of the front-rear direction as it approaches the center in the left-right direction of the concrete substructure. PC steel can be arranged in a convex manner in the horizontal direction, so that the PC steel support block can be pressed against the concrete substructure, and multiple PC steel support blocks can be arranged at intervals in the left-right direction. However, since all PC steel support blocks can be pressed against the concrete substructure, even if the upper structure such as a cross beam collides with the PC steel support block during an earthquake, the PC steel support block Resistance can be increased.

  According to the third invention, the steel PC steel support bracket can be easily fixed to the precast concrete block by the anchor bolt, and the laterally tightened PC steel material is supported by the steel PC steel support bracket. Further, since the PC steel material support bracket is arranged outside the precast concrete block, a large PC steel support block can be obtained without applying a large tensile force to the precast concrete block.

  Further, according to the fourth invention, the precast concrete block and the steel horizontal fastening PC steel material fixing bracket can be easily fixed by the anchor bolts fixed to the precast concrete block, and the steel PC Since the steel material fixing bracket is arranged outside the precast concrete block, a large PC steel material fixing block can be obtained without applying a large tensile force to the precast concrete block.

    Next, the present invention will be described in detail based on the illustrated embodiment.

  First, referring to FIG. 6, a concrete block 2 constituting an inner portion of a PC steel material support block 1 disposed on both sides in a bridge axis direction of a concrete substructure such as an abutment or an abutment will be described. The concrete block 2 is a concrete block 2 that is locked to the upper surface of the lower structure 3 and is disposed so as to face the bridge axis direction. A precast concrete block having an inverted L-shape as a whole and having an upper locking portion 4 that also serves as a girder support stopper and a vertical portion 5 that extends integrally with the upper locking portion 4 in the vertical direction. The upper locking portion 4 is perpendicular to the vertical portion 5 and includes a plurality of PC steel material insertion holes 6 at intervals in the direction perpendicular to the bridge axis and a fixing recess 7 at the end thereof. Yes.

  A plurality of female screw fittings 8 such as a plurality of inserts are embedded and fixed at an intermediate portion in the vertical direction of the vertical portion 5 in the concrete block 2 and spaced in the vertical direction.

  A plurality of anchor bolt insertion holes 9 are provided at the lower portion of the vertical portion 5 and spaced in the left-right direction, and fixing concave portions 10 are provided at the ends thereof.

  Next, about the structure of the steel laterally-tightening PC steel material support bracket 11 which comprises the outer part in the said PC steel material support block 1 and is fixed to the said inner concrete block 2, FIG. 8 (a) (b) ) (C), a laterally extending PC steel material support lateral groove (concave portion) 12 is provided in the outer intermediate portion of the laterally tightened PC steel material support bracket 11, and the PC steel material support lateral groove ( The cross-sectional shape of the concave portion 12 is a transverse groove 12 having an arc-shaped cross section in the direction perpendicular to the bridge axis, and the horizontal fastening PC steel material support bracket 11 is spaced in the vertical direction and spaced in the left-right direction. A plurality of bolt insertion through holes 13 are provided.

  The thickness T in the bridge axis direction of the laterally tightened PC steel material support bracket 11 is set at the end portion in the direction perpendicular to the bridge axis for the laterally tightened PC steel material support bracket 11 arranged at the center side in the perpendicular direction of the bridge axis. It is comprised so that it may become thick compared with the thickness of the horizontal fastening PC steel material support bracket 11 arrange | positioned, ie, the protrusion length of a bridge axis direction may become long.

  In the state where a plurality of the above-mentioned laterally tightened PC steel material support brackets 11 are disposed, the laterally tightened PC steel material which is disposed symmetrically with respect to the central axis in the bridge axis direction and is convex outward in the direction perpendicular to the bridge axis. 14 are arranged so as to be supported by touching in the horizontal grooves 12 for support, are supported by the horizontal grooves 12 for support, and are mounted so as to be pressed against the lower structure 3 by the PC steel material 14 laterally tightened.

  A PC made of a concrete block 2 and a side fastening support bracket 11 is fixed to a female screw fitting 8 embedded and fixed in the concrete block 2 in the bridge axis direction by a bolt 11 or the like. A steel support block 1 is configured. In the construction of the PC steel support block 1, the inner concrete block 2 is first fixed to the upper part of the concrete substructure 3, and then the PC steel support bracket 11 is fixed to the concrete block 2. The

  Next, referring to FIG. 7, the concrete substructure 3 such as an abutment or an abutment is locked to both upper surfaces on both sides in the direction perpendicular to the bridge axis (left and right direction) and is disposed so as to face the direction perpendicular to the bridge axis. The concrete block 17 constituting the inner side of the PC steel material fixing block 16 will be described. The concrete block 17 is made of rubber or the like on the upper locking portion 4 protruding toward the inner side, that is, the center side in the direction perpendicular to the bridge axis. The main girder support stopper 18 is made of an elastic support, and is a precast concrete block having a substantially inverted L shape as a whole, which is composed of a vertical portion 5 extending integrally with the upper locking portion 4 in the vertical direction. The upper locking portion 4 is perpendicular to the vertical portion 5, and the main girder support stopper 18 inside the upper locking portion 4 is fixed by a bolt or an anchor bolt. It is.

  A plurality of female screw fittings 8 such as inserts are embedded and fixed at an intermediate portion in the vertical direction of the vertical portion 5 in the concrete block 17 with a space in the vertical direction and a space in the left and right direction.

  A plurality of anchor bolt insertion holes 9 are provided at the lower portion of the vertical portion 5 and spaced in the front-rear direction, and fixing concave portions 10 are provided at the ends thereof.

  Next, regarding the configuration of the steel PC steel material fixing bracket 19 that forms the outside of the PC steel material fixing block 16 in the direction perpendicular to the bridge axis and is fixed to the inner concrete block 17, FIG. (B) Describing with reference to (c), both sides of the PC steel material fixing bracket 19 in the front-rear direction are close to the center of the side surface 21 from the middle part in the vertical direction (the center part in the figure). A horizontal PC steel material insertion hole 20 penetrating therethrough is provided, and each side surface 21 is provided with a substantially V-shaped concave portion 22 having an inclined support surface, and the PC steel material fixing bracket 19 is provided in the bracket 19 for fixing the PC steel material. Are provided with a plurality of through holes 23 for inserting anchor members at intervals in the front-rear direction and at intervals in the left-right direction.

  A PC steel material fixing bracket 19 is fixed to the female screw fitting 8 in the concrete block 17 perpendicular to the bridge axis by bolts or the like, and the concrete block 17 and the PC steel material fixing bracket 19 constitute a PC steel material fixing block 16. Is done.

  Next, FIG. 3 to FIG. 3 show the construction procedure from the concrete blocks 2 and 17 and the PC steel material support bracket 11 or PC steel material fixing bracket 19 to the state shown in FIGS. This will be described with reference to FIG.

  First, as shown in FIGS. 3 (a) to 3 (c), so as to be positioned between the main girders 24 and to face the bridge axis direction so as to sandwich the upper end of the concrete substructure 3. 6, the pair of concrete blocks 2 shown in FIG. 6 are spaced apart in the direction perpendicular to the bridge axis so as to allow expansion and contraction of the main girder 24 by spacing the end cross beams 28. A plurality of sets are arranged over the overhanging flange, and the lower surface of the upper locking portion 4 and the inner side of the vertical portion 5 of the concrete block 2 are on the upper surface of the concrete lower structure 3 and the front surface (or rear surface) in the bridge axis direction. Arrange and hold by appropriate support (not shown).

  A connecting PC steel material 25 is arranged across the PC steel material insertion through hole 6 of the upper locking portion 4 in the opposing concrete block 2, and a non-shrink mortar 26 is provided on the upper surface and upper side surface of the lower structure 3. After the non-shrinking mortar 26 is cured, these are tension-fixed by a fixing metal fitting such as a nut provided at the end of the connecting PC steel material 25 in the fixing recess 7 on the outside of each concrete block 2.

  The connecting PC steel material 25 is supported by effectively utilizing the gap G between the end cross beam 28 formed by supporting the main beam 24 by the support device 27 and the upper surface of the lower structure 3. It is arranged so as to be slightly lifted from the upper surface of the lower structure 3 while being shifted laterally from the device 27.

  Further, one end of the anchor bolt 30 is fixed to the female screw fitting 29 that is embedded and fixed in the anchor hole that is shallowly drilled at a position away from the upper end on both the front and rear sides in the bridge axis direction of the concrete substructure 3. At the same time, the anchor bolt 30 is inserted into the anchor bolt insertion hole 9 in the lower part of the concrete block 2 and fixed in the lower fixing recess 10 of the concrete block 2 with a nut or the like.

  As shown in FIG. 5, a steel PC steel support bracket 11 is arranged on the outer surface of the concrete block 2, and an anchor bolt 31 having one end connected to the female screw fitting 8 at the concrete block 2. Is inserted into the bolt insertion through hole 13 of the PC steel material support bracket 11 and fixed by a fixing metal fitting 32 such as a nut to constitute the PC steel material support block 1.

  As described above, the PC steel support block 1 is installed between the main girders while being spaced in the direction perpendicular to the bridge axis.

  Next, as shown in FIG. 4, a pair of concrete blocks 17 shown in FIG. 7 are opposed to each other in the direction perpendicular to the bridge axis on both upper side surfaces in the direction perpendicular to the bridge axis (left and right direction) of the concrete substructure 3. And arranged so that the lower surface of the upper locking portion 4 and the inner side of the vertical portion 5 of the concrete block 17 are opposed to the upper surface of the concrete lower structure 3 and the front or rear surface in the bridge axis direction. Hold by work (not shown).

  Further, the non-shrink mortar 26 is interposed between the upper surface and the upper side surface of the upper structure 3 to cure the non-shrink mortar 26.

  In addition, one end portion of the anchor bolt 33 is fixed to the female screw fitting 29 embedded and fixed in the concrete lower structure 3, and the anchor bolt 33 is inserted into the anchor bolt insertion hole 9 in the lower portion of the concrete block 17. In the lower concave portion 10 of the concrete block 17, fixing is performed by a fixing metal fitting 36 such as a nut.

  As described above, the concrete block 17 facing the direction perpendicular to the bridge axis is disposed, and as shown in FIGS. 5A and 5B, the steel PC steel material is fixed on the outer surface of the concrete block 17. The bracket 19 is arranged, and the anchor bolt 34 connected and fixed to the female screw fitting 8 of the concrete block 17 is inserted into the insertion hole 23 of the PC steel fixing bracket 19 and fixed by the fixing fitting 37, and the PC steel A fixing block 16 is configured.

  Next, as shown in FIG. 5, PC steel materials 14 such as outer cables are arranged on both the front and rear sides in the bridge axis direction, and the intermediate portion of each laterally tightened PC steel material 14 is a lateral groove 12 for supporting the PC steel material supporting bracket 11. The end portions of the laterally tightened PC steel material 14 are inserted into the insertion holes 20 of the PC steel material fixing brackets 19 on both sides in the direction perpendicular to the bridge axis, and the fixing metal fittings 38 are used to fix the tension.

  FIG. 1 and FIG. 2 show an embodiment in which the falling bridge prevention device of the present invention is implemented on an existing bridge as described above.

  As shown in FIGS. 1 and 2, from an existing state in which an upper structure 35 is supported by a concrete lower structure 3 such as an existing pier or an abutment via a support device 27, a bridge abutment or an pier PC steel support block 1 and PC steel fixing block 16 are installed on both sides of the upper part in the front-rear direction (bridge axis direction) and both sides of the upper part in the left-right direction (bridge axis perpendicular direction) in the concrete substructure 3, respectively. The PC steel support block 1 facing both side surfaces in the bridge axis direction is fixed by the connecting PC steel material 25 in the bridge axis direction, and the PC steel material fixing block 16 facing both sides in the left-right direction (the direction perpendicular to the bridge axis) is By fixing the end portion of the laterally tightened PC steel material 14 arranged on the outside of the PC steel material support block 1 which is arranged over these and faces both side surfaces in the bridge axis direction, It is fixed so as to press the chromatography preparative made lower structure 3.

  In the above embodiment, the PC steel material support block 1 in the PC steel material support block 1 and the PC steel material insertion hole of the PC steel material fixing bracket 19 are provided at the same level. The lower structure 3 can be made to press in the horizontal direction to be supported from the outside, and the PC steel material 14 can be supported in a stable state by the PC steel material support block 1.

  The PC steel support block 1 is a PC steel support block 1 having a long projecting length in the bridge axis direction up to the PC steel support lateral groove 12 as it approaches the center of the bridge axis perpendicular direction. Since the groove bottom portion of each PC steel material supporting horizontal groove 12 is on an arcuate locus having the same curvature, the pressing force can be applied to each PC steel material supporting block 1 evenly by the laterally tightening PC steel material 14.

  In addition, in the said embodiment, the thickness (protrusion dimension) of the longitudinal direction 5 of the vertical part 5 of the block 2 made from precast concrete is made constant, and the length of the bridge direction of the PC steel material support bracket 11 is changed. However, the thickness of the vertical portion 5 may be changed, and the length of the PC steel material support bracket 11 may be made constant.

  When carrying out the present invention, a PC steel wire, a PC steel stranded wire, a PC steel rod, or the like can be used as the laterally tightened PC steel material 14.

It is a partially longitudinal front view showing a fallen bridge prevention device of one embodiment of the present invention. FIG. 2 is a partial cross-sectional plan view of FIG. 1. It is explanatory drawing which shows the construction process of the fallen bridge prevention apparatus of this invention, (a) is a schematic longitudinal front view, (b) is a schematic longitudinal side view, (c) is a schematic cross-sectional top view. It is explanatory drawing which shows the construction process of the fallen bridge prevention apparatus of this invention, (a) is a schematic longitudinal front view, (b) is a schematic longitudinal side view, (c) is a schematic cross-sectional top view. It is explanatory drawing which shows the construction process of the fallen bridge prevention apparatus of this invention, (a) is a schematic longitudinal front view, (b) is a schematic longitudinal side view, (c) is a schematic cross-sectional top view. The typical form of the block made from a precast concrete arrange | positioned at the both sides of the bridge axis direction of a lower structure part is shown, Comprising: (a) is a front view, (b) is a vertical side view. The block made from a precast concrete arrange | positioned at the both sides of the bridge axis orthogonal direction of a lower structure part is shown, Comprising: (a) is a front view, (b) is a partially longitudinal side view. The PC steel material support bracket arrange | positioned on the outer side in the block for PC steel material support is shown, Comprising: (a) is a front view, (b) is a side view, (c) is a top view. 1 shows a PC steel material fixing bracket disposed outside a PC steel material fixing block, in which (a) is a front view, (b) is a side view, and (c) is a bottom view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 PC steel material support block 2 Concrete block 3 Lower structure 4 Upper latching part 5 Vertical part 6 PC steel material insertion hole 7 Fixing recessed part 8 Female screw metal fitting 9 Anchor bolt insertion hole 10 Fixing recessed part 11 PC steel material support bracket 12 PC steel material transverse groove 13 Bolt insertion hole 14 Horizontally tightened PC steel material 15 PC steel material support block 16 PC steel material fixing block 17 Concrete block 18 Main girder support stopper 19 PC steel material fixing bracket 20 PC steel material insertion hole 21 Side 22 Recess 23 Through hole 24 Main girder 25 PC steel 26 for connection 26 Non-shrink mortar 27 Bearing device 28 End cross girder 29 Female screw fitting 30 Anchor bolt 31 Anchor bolt 32 Fixing fitting 33 Anchor bolt 34 Anchor bolt 35 Superstructure 36 Fixing bracket 37 Fixing bracket 38 Fixing bracket

Claims (4)

  On both sides of the concrete substructure in the front-rear direction, each PC steel support block having an upper locking portion that also serves as a cross-girder support stopper is arranged so as to be locked to the upper surface of the concrete substructure, The upper and lower PC steel support blocks are connected to each other by a connecting PC steel member disposed in the gap between the upper and lower structures across the upper locking portion and fixed to the concrete lower structure. PC steel material fixing blocks having upper locking parts that also serve as main girder support stoppers on both sides are arranged so as to be locked to the upper surface of the concrete substructure, and the outside of the PC steel material support blocks on both sides in the front-rear direction Tighten the laterally tightened PC steel placed so that it is supported by the PC steel fixed block placed on both sides in the left-right direction. Girder prevention device, characterized in that the.   A plurality of PC steel support blocks that oppose the front-rear direction are arranged at intervals in the left-right direction, and the protrusion length in the front-rear direction increases as the distance from the center of the concrete substructure increases toward the left-right direction. 2. The falling bridge prevention device according to claim 1, wherein the laterally tightened PC steel materials arranged on the outer sides of the PC steel material support blocks arranged on both side surfaces are arranged in a substantially circular arc shape.   The PC steel support block is composed of a precast concrete block fixed to a concrete substructure and a steel PC steel support bracket fixed to the concrete block with anchor bolts. The fallen bridge prevention device according to claim 1, wherein the fallen bridge prevention device is supported by a PC steel material support bracket.   The PC steel fixing block is composed of a precast concrete block fixed to the concrete substructure and a steel PC steel fixing bracket fixed to the concrete block with anchor bolts. The fallen bridge prevention device according to claim 1 or 2, wherein the fallen bridge prevention device is fixed to a PC steel material fixing bracket.

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