JP4569878B2 - Bridge girder construction method - Google Patents

Description

  The present invention relates to a bridge girder construction method, and more particularly to a bridge girder construction method in which the construction of column heads prior to the construction work is streamlined when a bridge girder such as a high pier is overhanged and constructed by the construction method.

  FIG. 7 is an overall view showing an example of a high pier bridge 50 constructed in a valley 51 in a mountainous area. In such construction work of the bridge 50, an overhang construction method (cantilever construction method), which is a construction method of constructing a bridge girder 53 between the abutment 51 on both banks and the high pier 52 at the intermediate support position, is adopted. Many. FIG. 8 is an explanatory view schematically showing a situation where the bridge 50 shown in FIG. 7 is being constructed by the overhanging construction method. As shown in FIG. 8, using a plurality of mobile work vehicles 60 assembled at the column heads 52 a of the high piers 52, the abutment 51 constructed from the position of each pier 52 to the intermediate joint position of the beam span or the slope. The bridge girder 53 is constructed by continuously constructing and extending the bridge girder 53 in a cantilever manner.

  In this overhanging construction method, a girder block having a predetermined span is connected and constructed using a mold suspended from a mobile work vehicle. In the work space for constructing this girder block, an outer periphery scaffold is assembled, and the safety of construction in each girder block is ensured. Specifically, in the work space on the work floor surrounded by the outer periphery scaffold, located below the mobile work vehicle, work of rebar assembly, PC cable sheath piping, formwork assembly, concrete placement, After the concrete curing period, a series of work is performed until the formwork dismantling. Then, the movable work vehicle is moved to the position where the adjacent block can be constructed, and the girder block is constructed in the next process. In the construction process of the bridge girder block that is repeated in this way, the work content in each process is almost fixed, and therefore it is considered difficult to shorten the construction period in each process. In order to solve this problem, the concrete bridge erection method and erection device disclosed in Patent Document 1 have been proposed.

  In this concrete bridge erection method, when construction to the pier top is completed, by using the work scaffold around the pier that was assembled to construct this pier, as it is, the pier column head is built up as it is, It has been proposed to shorten the construction period.

JP-A-6-185018.

  However, the feature of the erection device disclosed in Patent Document 1 described above is for the purpose of shortening the process in the overhanging girder erection process as described above, and while suspending the outer formwork on the front end side in the traveling direction of the mobile work vehicle, It is in the point which provided the work scaffold which can carry out an internal formwork and rebar assembly in advance. For this reason, it is not intended to shorten the construction period in a series of processes such as the construction of the pillar head, the dismantling process of the supporting work for the pillar head construction, and the assembly of the mobile work vehicle. Since this column head construction is usually performed by a conventional formwork method, the construction of the column head is completed, and after completion of the dismantling process of the formwork, scaffolding, etc., the mobile work vehicle This is the assembly process.

  By the way, conventionally, a work floor that performs the same function as a work scaffold used for pillar head construction has been incorporated and used in a form of being suspended from a mobile work vehicle even during the construction process of a girder block. By sharing these work floors and constructing the work floors early, scaffold assembly work for bridge girder construction can be carried out ahead of schedule. Therefore, the object of the present invention is to solve the problems of the above-described conventional technology, and in the construction process of the column head and the assembly process of the mobile work vehicle, the materials for temporary work, the sharing of the equipment, the respective assembly, the disassembly of The purpose is to provide a bridge girder erection method and a bridge girder erection method so as to shorten the process in erection of the bridge girder by adjusting the timing.

In order to achieve the above-mentioned object, the present invention advances a mobile work vehicle assembled with a bridge pier column head over a girder block constructed by overhanging and connecting and connecting girder blocks continuous to the girder block. In a bridge girder construction method in which bridge girder is constructed between pier spans, a work floor used in the mobile work vehicle is preliminarily used as a temporary work floor for constructing the column head of the pier, and the work floor surface is used. the erected a temporary work scaffolding the capital unit built and configured, upright an outer scaffold surrounding the area of the overhanging erection work by the moving working vehicle to the work floor in parallel with the column capital portion building work, the After completion of the column head, the movable work vehicle is assembled on the column head, and the work frame for constructing the girder block and the work floor on which the outer periphery scaffold is left are suspended by a suspension member provided on the mobile work vehicle. And said move The work vehicle is traveling in the digit direction is characterized in that so as to start the overhanging erection work digits block bridge girder continuous to the stigma section.

A mobile work vehicle assembled at the head of the pier column is advanced over the girder block constructed by overhanging, and the girder block connected to the girder block is connected and constructed so that the bridge girder is installed between the pier spans. In the construction method of the bridge girder, the work floor used in the mobile work vehicle is laid in advance and used as a temporary work floor for constructing the column head of the pier, and the temporary work scaffold is erected on the work floor surface. In parallel with the pillar head construction work, an outer periphery scaffolding is set up on the work floor to surround an overhanging construction area by the mobile work vehicle, and the movement onto the pillar head is completed after the pillar head is completed. A suspension receiving member for assembling the work vehicle and for suspending the formwork for building the girder block and the work floor on which the outer periphery scaffold is left at different heights of the suspension member provided on the mobile work vehicle. Installation , Supporting the formwork and the work floor at each installation position of the suspension receiving member, and moving the movable work vehicle in the direction of the spar to start the work of overhanging the girder block of the bridge girder continuous with the column head It was made to do.

The bottom form of the girder block is placed on the work floor to construct the pillar head, and after the completion of the pillar head, the suspension member is arranged on the mobile work vehicle to set the height of the bottom form. It is preferable to adjust the height of the suspension receiving member provided on the bottom of the girder block and to install the bottom mold frame at the bottom surface of the girder block .

  According to the present invention, in the construction process of the pier column head and the assembly process of the mobile work vehicle at the column head, by sharing the materials and equipment of the mobile work vehicle, by adjusting the timing of their assembly and disassembly, There is an effect that it is possible to shorten the process in the construction work of the bridge girder.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments as the best mode for carrying out a bridge girder erection method and a bridge girder erection method of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the top of a reinforced concrete pier 2 (hereinafter simply referred to as a pier 2) constructed by a known formwork method or slip form method in a bridge (FIG. 7) as an example of a construction object. It is the elements on larger scale which showed (circle | circle mark position). A column head 2a (indicated by a two-dot chain line) serving as a fulcrum of the bridge girder is constructed on the top of the pier 2. The column head of this pier is integrated with the pier and serves as a continuous fulcrum for the bridge girder.
Hereinafter, the construction procedure of the column head 2a will be described with reference to FIGS.

  Prior to the construction of the column head 2a, as shown in FIG. 2, the bracket scaffold 10 is attached to a predetermined height of the concrete side wall surface above the pier 2. The bracket scaffold 10 includes a standing member 11 fixed to an anchor (not shown) at a predetermined interval along a concrete side wall surface, and a receiving beam horizontally disposed from the upper end of each standing member 11 to the side. 12 and a wand 13 that supports the receiving beam 12.

  Further, a work floor 21 of a mobile work vehicle 20 (see FIG. 5) used in a later overhang construction method is laid on the bracket scaffold 10 (FIG. 3). The work floor 21 is laid on the bracket scaffold 10 via a joist (not shown) assembled in a lattice shape, and thereby has a predetermined area that forms a square shape around the pier 2 in plan view. Work space is secured. Further, the work floor 21 is placed on the bracket scaffold 10 with the suspension receiving member 23 that is later suspended by the suspension member 22 of the mobile work vehicle 20 as a pedestal. For this reason, when it is later incorporated into the mobile work vehicle 20, the suspension receiving member 23 is fixed to the suspension point position of the predetermined level (height) of the suspension member 22, so that it can be easily used as the work floor 21 of the mobile work vehicle 20. Can be reassembled and used.

  Further, as shown in the right half of FIG. 3, a mold member constituting the bottom mold 25 of the girder block 5 is placed on the work floor 21 in advance. Also in this case, as in the case of the work floor 21, it is preferable to use the suspension receiving member 24 that can be suspended from the mobile work vehicle 20 by the suspension member 22 as a base. When the support points of the work floor 21 and the bottom mold 25 are not sufficient only by the suspension receiving members 23 and 24, it is preferable to add support points (not shown) on the bracket scaffold 10 and the work floor 21 as appropriate. .

  Next, as shown in FIG. 4, the pillar head 2 a is constructed on the work floor 21. The work floor 21 as a work scaffold is assembled in accordance with the outer peripheral dimensions of the pier 2 and, first, rebar assembly and formwork assembly of the column head 2a are performed using this work scaffold. As shown in the left half view of FIG. 4, an overhanging outer periphery scaffold 26 is assembled on the work floor 21 in parallel with the construction period from the completion of the formwork assembly to the concrete placing work of the column head 2a. This outer periphery scaffold 26 is a known frame scaffold assembled to the extent that the entire spar block 5 can be covered, and a safety net is stretched over the entire outer periphery of the scaffold. It functions as a safety facility that covers the entire space. It also serves as a safety facility for workers when constructing the column head 2a.

The mobile work vehicle 20 is assembled on the pillar head after the concrete curing period of the pillar head 2a has elapsed or when the concrete has reached a predetermined strength. As shown in FIG. 5, the mobile work vehicle 20 is composed of a known steel truss structure frame having a traveling mechanism or a movable support that can be pulled horizontally, and two vehicles are directed from the column head 2a in both directions. It is assembled symmetrically with respect to the pier center line. A plurality of suspension members 22 are suspended from suspension girders (not shown) which are incorporated perpendicularly to the upper string truss of each mobile work vehicle 20 and whose both ends extend outward from the bridge girder width. The suspension member 22 supports the above-described work floor 21 and the total loads of the plurality of molds of the girder block 5 at predetermined suspension point positions. The work floor 21 is always held horizontally and suspended by a suspension receiving member 23. However, the suspension receiving member 24 as a suspension point of the bottom mold 25 has a lower girder block height as it extends and the construction progresses. The height is adjusted to the position of the bottom mold frame in accordance with the height of the girder block and fixed to the suspension member 22.

  As shown in FIG. 6, the mobile work vehicle 20 is run on the completed girder block 5 and moved to the tip position of the completed girder block 5, so that the girder block 5 in the next process is installed. The bracket scaffold 10 anchored to the concrete wall of the bridge pier can be removed at the stage where the work scaffold 20 and the work scaffold suspended on the mobile work vehicle 20 and the outer periphery scaffold 26 have left the pier.

  After that, based on the procedure of the known overhang construction method, the girder block 5 is successively constructed, and the span block 5 overhanging from both sides is connected at the middle span position between the bridge piers, or one span is constructed, or In the end span, erection to the abutment position will be performed.

  In this way, the work floor 21 of the mobile work vehicle 20 is also used as the work floor 21 for the construction of the head 2a, and is used as a part of the equipment of the mobile work vehicle 20 when the mobile work vehicle 20 is assembled. At the time of construction of the part 2a, the outer scaffold 26 for overhanging construction can be assembled on the work floor 21, and then the bracket scaffold 10 attached to the pier 2 can be disassembled and removed after the overhang construction starts. As described above, since the above-described work, which has been a critical path in the process in the construction stage of the column head 2a and the assembly stage of the mobile work vehicle 20, can be performed in parallel with the progress of the main work, The process before starting can be greatly shortened.

The enlarged view of the pier top part which showed the state before pillar head construction. The enlarged view of the pier top part which showed the state in which the bracket scaffold was provided. The enlarged view of the pier top part which showed the state which laid the work floor of the mobile work vehicle on the bracket scaffold. The enlarged view of the bridge pier top part which showed the state which assembled the outer periphery scaffold for overhang construction as a parallel operation at the time of pillar head construction. The enlarged view of the pier head which assembled the mobile work vehicle in the upper part of a pillar head, and showed the form installation state for overhang construction. The enlarged view of the pier head which showed the overhang construction situation by a mobile work vehicle. Explanatory drawing which showed the whole bridge shape of a high pier. Explanatory drawing which showed the construction state of the bridge shown in FIG.

Explanation of symbols

2 Pier 2a Column head 5 Girder block 10 Bracket scaffold 20 Mobile work vehicle 21 Work floor 22 Suspension member 23 Suspension receiving member 25 Bottom formwork 26 Outer periphery scaffold

Claims (3)

A mobile work vehicle assembled at the head of the pier column is advanced over the girder block constructed by overhanging, and the girder block connected to the girder block is connected and constructed so that the bridge girder is installed between the pier spans. In the construction method of the bridge girder,
As temporary working floor of applying the capital portion of the pier, using previously laid working floor for use in the mobile work vehicle, the capital portion and built structure erected a temporary work scaffolding on the working floor, In parallel with the pillar head construction work, an outer periphery scaffolding that surrounds an overhang construction area by the mobile work vehicle is erected on the work floor, and the mobile work vehicle is assembled on the pillar head after the completion of the pillar head, A suspension member provided on the mobile work vehicle is used to suspend a formwork for building a girder block and the work floor on which the outer periphery scaffold is left, and the mobile work vehicle is advanced in the direction of the girder to move to the column head. A construction method of a bridge girder characterized by starting overhang construction work of a girder block of continuous bridge girder. A mobile work vehicle assembled at the head of the pier column is advanced over the girder block constructed by overhanging, and the girder block connected to the girder block is connected and constructed so that the bridge girder is installed between the pier spans. In the construction method of the bridge girder,
As a temporary work floor for constructing the pillar head of the pier, a work floor used in the mobile work vehicle is laid in advance, and a temporary work scaffold is erected on the work floor surface to construct the pillar head, In parallel with the pillar head construction work, an outer periphery scaffolding is provided on the work floor to surround an overhang construction area by the movable work vehicle, and after the completion of the pillar head, the movable work vehicle is assembled on the pillar head, A suspension receiving member for suspending the formwork for constructing the girder block and the work floor on which the outer periphery scaffold is left is installed at different heights of the suspension members provided in the mobile work vehicle. The formwork and the work floor are supported at the respective installation positions of the members, and the mobile work vehicle is advanced in the direction of the spar to start the overhanging work of the girder block of the bridge girder continuous with the column head. Bridge girder characterized by Erection method. The bottom form of the girder block is placed on the work floor to construct the pillar head, and after the completion of the pillar head, the suspension member is arranged on the mobile work vehicle to set the height of the bottom form. The bridge girder according to claim 2, wherein the height of the suspension receiving member provided on the girder block is adjusted, and the bottom mold is installed at the bottom surface height of the girder block continuous to the girder block . Construction method.
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