JP3164031U - Fixing structure of telescopic device - Google Patents

Abstract

The present invention provides a fixing structure for a bridge expansion / contraction device that can be applied to a bridge having a thin floor slab thickness. A bridge expansion and contraction device (1) fixes a plurality of perforated divels (3) in parallel to a lower surface of a face plate (2). The perforated gibels 3 are formed in a plate shape and are arranged in parallel in the transverse direction of the bridge with a predetermined interval, and two through holes 4 and 4 are formed in each plate material. Through-hole reinforcing bars 5 are respectively inserted into the through-holes 4 located in the same row, and a substantially U-shaped covering bar 6 in the lateral direction is orthogonal to the reinforcing bars 5 passing through the hole 4 on the rear end side of the face plate 2. Install. The covering muscle 6 can be expected to hold down the uplifting action of the dowel, and can have sufficient strength against the design load even if the product height of the product is lowered. Volume decreases. [Selection] Figure 1

Description

  The present invention relates to a fixing structure of a bridge expansion / contraction device in which a perforated diver integrally molded with a face plate is embedded in a concrete floor slab.

  Telescopic devices used in bridges, such as road bridges, can cope with the expansion and contraction of floor slabs caused by bending of vehicles, etc., temperature changes, etc. The configuration is such that generation can be suppressed.

As a conventional bridge expansion and contraction device having such a function, there has been a structure as described in Patent Document 1, for example.
JP 2004-143845 A

  A conventional expansion / contraction device includes a pair of face plates and a plurality of perforated gibels projecting outwardly from the end portions, and the perforated divels are formed into a plate shape and spaced apart from each other by a predetermined interval. They were arranged in parallel in the transverse direction, and each plate member had two through holes.

  The perforated gibber is embedded in the concrete at the edge of the bridge floor slab to prevent displacement and opening between the face plate and the concrete. It counteracts the rotational force acting when passing through the vehicle. It was intended to suppress the movement in the long direction and prevent the extension device from falling off the floor slab.

  The through hole provided in the perforated gibber functions as a means for increasing the above-mentioned resistance force by inserting the cast concrete, and the concrete filled in the through hole with respect to the acting shear force It was a structure that resisted by the circular side surface of columnar concrete by the joining action.

  As described above, since the through hole in the perforated dive of the conventional expansion and contraction device is mainly structured to resist only by the connecting action of the concrete, in order to maintain a sufficient resistance, a large hole cross section, that is, a sufficient dive height. Was necessary. Therefore, the size of the conventional expansion / contraction device is, for example, about 210 mm when the allowable expansion / contraction amount is 160 mm, and the application range is limited by the size of the product. there were.

  In other words, when the bridge slab thickness is thin and the floor slab notch depth required to install the telescopic device cannot be secured, or when it is impossible to remove the slab to the notch depth required for replacement of the telescopic device Etc. could not be used.

  Also, in the construction of replacing the expansion / contraction device, there is a problem that the time for traffic regulation becomes long if the depth of cutout of the concrete is large. Moreover, in the removal work of the existing expansion / contraction apparatus, since the crusher was used, the damage to the existing floor slab and the reinforcing reinforcing bar at the end of the floor slab were concerned as the notch depth increased.

  This device is intended to solve the above-mentioned problems of the fixing structure of the conventional expansion and contraction device of the bridge, and has sufficient proof strength against the design load, but it can be applied to a bridge with a thin floor slab thickness. The purpose of the present invention is to provide a fixing structure for a bridge expansion / contraction device that can be applied, can shorten the replacement time of the expansion / contraction device, and is less likely to damage an existing floor slab and a reinforcing bar at the end of the floor slab. .

  In order to solve the above problems, the fixing structure of a bridge expansion / contraction device according to the present invention is a bridge expansion / contraction device in which a plurality of perforated divels fixed in parallel to the lower surfaces of a pair of opposed face plates are embedded in concrete. In this fixing structure, the fixing structure includes a through-hole reinforcing bar penetrating each hole located in the same row of the perforated gibbles, and a covering bar disposed perpendicular to the upper surface of the through-hole reinforcing bar. To do.

  The covering bar is expected to have an effect of suppressing the uplifting action of the dowel, and abuts perpendicularly to the upper surface of the through hole reinforcing bar and fixes its end to the concrete. The cross-sectional area and the interval of the covering line are appropriately set according to the assumed pressing load, but for example, they are arranged in one or two rows at the same interval as the dowel.

  The covering reinforcement of the fixing structure of the bridge expansion and contraction device according to claim 2 is characterized by having a substantially U-shape in a lateral direction surrounding the through-hole reinforcing bar. The covering bar surrounds at least the penetrating reinforcing bar on the rear end side of the dowel, that is, the rear end side of the back face of the face plate, with the bottom of the U-shape, and presses it down. The upper part of the U-shape is embedded in the concrete for fixing the device to the required length.

  The fixing structure of the expansion / contraction device for the bridge according to the present invention can be expected to have an effect of suppressing the uplifting action of the diver because the covering bar is disposed on the upper surface of the reinforcing bar penetrating the perforated diver. Therefore, even if the member height of the product is lowered, it is possible to have a sufficient proof strength with respect to the design load, and it is possible to apply to a bridge with a thin floor slab thickness.

  Further, since the height of the member is lowered, the volume of the floor slab notch for installing the apparatus is reduced. Along with this, in the case of replacement work of the expansion and contraction device, it is possible to shorten the removal and installation work time by reducing the concrete notch depth, damage to the existing floor slab and damage to the reinforcing bar at the end of the floor slab, etc. The risk of

  In the fixing structure of the bridge expansion and contraction device according to claim 2, the covering line is formed in a substantially U shape in the horizontal direction, so that it can be fixed to the concrete in the notch portion, and the construction at the site becomes easy.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a perspective view showing a fixing unit on one side of the expansion / contraction device, FIG. 2 is a plan view thereof, and FIG. 3 is a cross-sectional view showing a III-III cross section of FIG.

  The bridge expansion and contraction device 1 fixes a plurality of perforated divels 3 in parallel to the lower surface of the face plate 2. The perforated dowels 3 are formed in a plate shape and are arranged in parallel in the transverse direction of the bridge with a predetermined interval, and two through holes 4 and 4 are formed in each plate material.

  Through-hole reinforcing bars 5 are inserted into the through-holes 4 located in the same row, respectively. The reinforcing bars 6 penetrating the holes 4 on the front end side of the back face of the face plate 2 are perpendicularly crossed with a substantially U-shaped covering bar 6 in the horizontal direction. Install.

  The covering bars 6 are arranged in two rows on both sides of the L-shaped assembling bars 7 arranged between the dowels 3, and the ends are fixed to the notched concrete 8 shown by a two-dot chain line in FIG. 3.

  In addition, 9 shown with the dashed-two dotted line of FIG. 3 shows floor slab concrete, 10 shows the connecting reinforcement embed | buried under this floor slab concrete 9, 11 shows the main reinforcement of a floor slab.

  When the vehicle passes over the face plate 2, an upward force is applied to the perforated gibber 3 by the load N of the vehicle. Therefore, in order to securely fix the expansion / contraction device 1 at the end of the floor slab, the perforated divel 3 needs to have sufficient rigidity with respect to the rotation direction of the expansion / contraction device 1.

  A load resistance test was performed using the expansion and contraction device shown in FIGS. The test is an expansion / contraction device when the allowable expansion / contraction amount is 160 mm, the floor slab notch depth shown in FIG. 3 is D = 190 mm (D = 230 mm in the case of the conventional type), D19 is the covering reinforcing bar 5 For No. 6, a D16 reinforcing bar processed into a substantially U shape in the horizontal direction was used. The interval between the holes 4 in the dowel 3 was set to 100 mm, similar to the interval between the main bars 11 of the floor slab.

The design standard strength of the concrete to be placed in the notch is 30 N / mm ² , the load to be loaded is 80 mm from the tip of the expansion device tooth tip, and the loading width is 500 mm in the central portion of the expansion device.

  As a test result, the maximum loading load was 546 kN, which was about 2.9 times the design load 189 kN. As for the behavior of the through-hole reinforcing bar 5 and the covering reinforcing bar 6 at this time, the generated strain of the through-hole reinforcing bar 5 gradually increases from around the loaded load N = 200 kN, and the upper side from around N = 300 kN is on the compression side, Was generated on the tension side and behaved in a convex shape on the lower side.

  In addition, the strain generated by the through-hole reinforcing bar 5 from N = 425kN to the occurrence of cracking changes from the compression side to the tension side, and the lower side from the tension side to the compression side. The generated strain of the covering muscle 6 has been expanded after N = 450 kN. Thereby, it can be inferred that the through-hole reinforcing bar 5 is resisting integrally with the covering bar 6.

  It has been found that the load bearing force is enhanced by the placement of the covering muscle 6 and effectively acts on the uplifting action of the dowel. The notch cross-section of the floor slab can be reduced by about 18% when the allowable expansion / contraction amount is 160mm, and the replacement time of the expansion / contraction device can be shortened by about 10%. Is possible.

It is a perspective view which shows the fixing | fixed part of the one side of an expansion-contraction apparatus. It is a top view which shows the fixing | fixed part of the one side of an expansion-contraction apparatus. It is sectional drawing which shows the III-III cross section of FIG.

DESCRIPTION OF SYMBOLS 1 Expansion / contraction apparatus 2 Faceplate 3 Perforated perforation 4 Through-hole 5 Through-hole rebar 6 Covering bar

Claims (2)

In a fixing structure of a bridge expansion / contraction device in which a plurality of perforated divels fixed in parallel to the lower surfaces of a pair of facing face plates are embedded in concrete, the fixing structure is located in the same row of the perforated divels A fixing structure for a bridge expansion and contraction device, comprising: a through-hole reinforcing bar penetrating each hole; and a covering reinforcing bar disposed perpendicular to the upper surface of the through-hole reinforcing bar. 2. The fixing structure for a bridge expansion / contraction device according to claim 1, wherein the covering bar has a substantially U-shape in a lateral direction surrounding the through-hole reinforcing bar.

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