JP2019214919A

JP2019214919A - Concrete edge widening structure that makes it easy to recover girder of superstructure after earthquake

Info

Publication number: JP2019214919A
Application number: JP2018123713A
Authority: JP
Inventors: 健行野村; Takeyuki Nomura
Original assignee: Alps Technos Co Ltd
Current assignee: Alps Technos Co Ltd
Priority date: 2018-06-12
Filing date: 2018-06-12
Publication date: 2019-12-19

Abstract

To provide a substructure edge widening structure which secures a work space for jack-up work performed after a superstructure girder is lowered in an existing bridge substructure.SOLUTION: A jack hole 2 is provided in a cast-in-place concrete edge widening structure. By providing the jack hole, it is possible to secure a work space for jacking up a girder for bearing replacement, not only for restoration after the girder has fallen, but also for repairing bridges and repairing bridges. If there is little gap between the bridge seat and the girder, and it is difficult to cast concrete with the widened edge structure, a casting area is lowered to a location where cast-in-place can be performed, and only the lowered area is filled with precast concrete blocks. Then, the jack hole 2 is provided so that a work space for jacking up can be secured.SELECTED DRAWING: Figure 3

Description

橋梁下部工コンクリート縁端拡幅構造Bridge widening concrete edge widening structure

既設橋梁落橋防止システムの設計手引き平成十一年三月日本橋梁建設協会Design Guide for Existing Bridge Falling Prevention System March 1999 Japan Bridge Construction Association

既設橋梁の耐震補強構造の内、落橋防止装置として下部工縁端拡幅構造がよく採用されている。このをもっと合理的な構造に変えることが本発明の解決しようとする課題である。Of the seismic retrofitting structures of existing bridges, the widening structure at the lower edge of the edge is often used as a bridge fall prevention device. Changing this to a more rational structure is the problem to be solved by the present invention.

既設橋梁下部工縁端拡幅構造は現場打コンクリートによるものが多いが、二つの欠点がある。Most of the existing bridge lower edge widening structures are made of cast-in-place concrete, but have two disadvantages.

一．縁端拡幅構造は地震時上部工の桁の落下を防止するために設けているが、地震力により桁が支承の上から橋座面や縁端拡幅構造のうえに落下したあとに、桁下面と橋座面や縁端拡幅構造の間に隙間がなく、桁をジャッキアップする作業スペースを確保できない。one. The edge widening structure is provided to prevent the girder of the superstructure from falling during an earthquake, but after the girder falls from the bearing onto the bridge seat or the edge widening structure, There is no gap between the bridge and the bridge seat surface or the edge widening structure, and it is not possible to secure a work space for jacking up the girders.

二．上部工の構造により支承の高さが非常に小さい場合がある。とくにコンクリートスラブ橋の場合は支承が薄く、橋座面と桁下間に隙間が狭いため、現場打コンクリート製縁端拡幅部を採用すると、コンクリート打設が困難である。このような理由により、経済的なコンクリート案が最初から外されて、拡幅手段が限られている。two. The height of the bearing may be very small due to the structure of the superstructure. Especially in the case of concrete slab bridges, the bearing is thin and the gap between the bridge seat surface and under the girder is narrow. For these reasons, economic concrete proposals have been removed from the outset and the means of widening have been limited.

本発明は課題を解決するための手段として二つがある。
一．現場打コンクリート縁端拡幅構造に図面２のジャッキ用穴（２）を設ける。ジャッキ用穴を設けることにより、地震後移動した桁の復旧は勿論、普段橋梁の補修で支承交換などが必要な場合に備えて桁をジャッキアップする作業スペースを確保できる。The present invention has two means for solving the problems.
one. The jack hole (2) shown in FIG. 2 is provided in the cast-in-place concrete edge widening structure. By providing jack holes, it is possible to secure the work space for jacking up the girder in case repairing of the girder moved after the earthquake is needed, as well as when the bridge needs to be replaced for repair of the bridge.

二．橋座面と桁下間の隙間が狭く、縁端拡幅構造のコンクリート打設が困難な場合は現場打部を打設できる位置に下げて、現場打部の天端と既設下部工天端の高さの差をプレキャストコンクリートブロックで埋める。地震時にプレキャストコンクリート嵩上げブロック（３）のずれがないように、樹脂による接着や図面３に示すＬ字の噛み合わせにより、プレキャストコンクリートブロックを安定させる。そして、ジャッキアップする作業スペースを確保できるように、図面３のジャッキ用穴（２）を設ける。ジャッキ用穴（２）よりやや小さめなコンクリートや木のブロック（図面３（４）ずれ止め用ブロック）をジャッキ用穴（２）に入れることで、プレキャストコンクリート嵩上げブロックの橋軸直角方向の移動をとめることも可能である。two. If the gap between the bridge seat surface and under the girder is narrow and it is difficult to cast concrete with an edge widening structure, lower it to a position where the cast-in-place can be cast and lower the top of the cast-in-place and the existing lower construction top. Fill the difference in height with precast concrete blocks. The precast concrete block is stabilized by bonding with a resin or engaging in an L-shape as shown in FIG. 3 so that the precast concrete raising block (3) does not shift during an earthquake. Then, a jack hole (2) in FIG. 3 is provided so that a work space for jacking up can be secured. By inserting a block of concrete or wood (block 3 (4) for preventing slippage) slightly smaller than the jack hole (2) into the jack hole (2), the movement of the precast concrete raising block in the direction perpendicular to the bridge axis can be achieved. It is also possible to stop.

一般的な橋梁下部工コンクリート縁端拡幅構造のイメージ図Image of general bridge substructure concrete edge widening structure 本発明の考え方により改良したの橋梁下部工において現場打コンクリート縁端拡幅構造In-place concrete edge widening structure for bridge substructure improved by the concept of the present invention 本発明の考え方により橋座面と桁下間が狭い場合でも現場打コンクリートとプレキャストコンクリートブロックと合わせた縁端拡幅構造Edge widening structure combined with cast-in-place concrete and precast concrete block even when the distance between the bridge seat and the girder is narrow according to the concept of the present invention

１現場打コンクリート拡幅部
２ジャッキ用穴
３プレキャストコンクリート嵩上げブロック
４ずれ止め用ブロック1 Cast-in-place concrete widening part 2 Hole for jack 3 Precast concrete raising block 4 Block for slip prevention

Claims

In-place concrete edge widening structure with jack holes (2) as shown in Fig. 2 in bridge substructure

In the substructure of the bridge, as shown in Fig. 3, the widened edge is combined with the cast-in-place concrete widening part and the raised precast block. Alternatively, as shown in FIG. 3, an edge widening structure having a jack hole (2).