JP2005113579A - Movable form support - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide movable form support capable of easily coping with a change in a curve radius. <P>SOLUTION: A bottom slab form 3 and a side surface form 4 of one unit divided in the bridge axis direction, are respectively independently slidably molded in the bridge axis crossing direction. The bottom slab form 3 can be slid in the bridge axis crossing direction so that the bridge axis directional center line of the bottom slab form 3, coincides with the planning linear center line of a bridge having a straight line section or a curve section. The side surface form 4 is rotatably arranged in a groove 31 of arranging a projection 43 arranged in the bridge axis directional center or in the vicinity of the bridge axis directional center among an under surface of the side surface form 4, in an outer edge part 32 in substantially parallel to the bridge axis direction of the bottom slab form 3, in a bridge axis directional central position or a bridge axis directional central vicinal position of the bottom slab form 3, to use the movable form timbering having a plurality of units composed of the bottom slab form 3 and the side surface form 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mobile formwork support used when building a bridge girder.

In the construction of prestressed concrete box girder bridges, there is a construction method in which cast-in-place construction is performed with a single push using a mobile formwork support. In this construction method, a continuous girder bridge is constructed while repeating concrete placement, demolding, and span movement to the next span for each span with an erection device placed above the pier.

The mobile formwork support described above generally includes components such as a girder, a hand extender, a support base, a frame, a bottom formwork apparatus, a side formwork, an inner formwork, and a bottom formwork opening / closing mechanism.
The girder is a steel beam-like member that extends in the direction of the bridge axis, serves as the backbone of the mobile formwork supporter, and has the function of transmitting loads such as formwork and concrete to the support base.
The hand extender is a lightweight girder or truss provided in front of a girder that plays a role of supporting a load in place of a girder at the time of refilling the support base in front of the span.
The support stand supports the girder and the billing machine from below, and transmits the weight of the movable formwork support and the concrete load to the bridge pier and the existing superstructure, and further provides a mechanism for moving to the next span. I have.
The frame is provided in a state of straddling the girder, and plays a role of supporting the bottom plate formwork and the side formwork via the vertical material and the suspension material.
The bottom plate formwork device is a formwork and support for a lower floor plate suspended from a frame, and is usually divided into units having a length of about 2 to 4 m in the bridge axis direction.
A side formwork is a formwork and formwork support work for the outside of the side wall (web) of the main girder and an overhanging slab.
The inner formwork is a formwork and formwork support for the inner side of the side wall (web) of the main girder and the upper floor slab.
The bottom plate formwork opening / closing mechanism is a mechanism for opening and closing a bottom plate formwork device provided in order to avoid a bridge pier that hinders movement when the movable formwork supporting work moves between spans. When dodging the pier, it is used to open the bottom formwork device and close it again after passing through the pier.

By the way, there are roughly two main girder design methods for constructing curved bridges. One of them is a method in which the main girder (or web) is a straight line, the center line of the route is approximated by a continuous broken line that bends on each pier, and the width of the running road surface is adjusted by the length of the overhanging slab. The other method is a method in which the main girder (or web) is curved and the length of the overhanging slab is hardly changed. This method is to fix the bottom plate formwork divided in the bridge axis direction, move each side formwork by the required amount in the direction perpendicular to the bridge axis, and rotate it around the vertical axis according to the curve to approximate the broken line. is there.

Patent Document 1 discloses a rotary bottom formwork b that is suspended from a mobile formwork support (mobile formwork carriage a). The bottom slab form b is provided with a rotating part c on both sides of the portal-type movable formwork carriage a so that the half slab bottom form form b can be rotated by the respective rotating part c. A bottom plate formwork is connected and integrated to form a formwork support and a formwork (see FIG. 5).
JP-A-10-204830

The conventional mobile formwork support and the bridge construction method using the mobile formwork support have the following problems.
<1> In the method in which the main girder (or web) is curved and the length of the overhanging slab is hardly changed, it takes a long time to install the side mold at a predetermined position. Furthermore, it is difficult to cope with a change in curve radius and an S-shaped curve.
<2> It is difficult to make the side surface formwork and the bottom formwork in close contact with each other, and the mortar content of the concrete is likely to leak from the joint. Therefore, there is a method of fixing with bolts in order to achieve sufficient adhesion. However, in the case of fixing with bolts, it is necessary to engrave a large number of bolt holes in the bottom plate formwork, and there is a problem that the appearance of the finish is impaired.
<3> It is difficult to construct the center of the side mold as the center of rotation of the side mold. Therefore, the center of rotation may not be the center of the side formwork, so the bridge constructed in such a state does not have a smooth curve due to uneven side surfaces (webs), resulting in a problem that the appearance is impaired. sell.

In order to solve the above problems, the mobile formwork support of the present invention is a mobile formwork support used when building a bridge girder, and the mobile formwork support is a bridge Each of the bottom plate mold and the side mold divided into one unit is formed so as to be slidable in the direction perpendicular to the bridge axis, and the bottom plate mold has a center line in the bridge axis direction of the bottom plate mold. It can be slid in a direction perpendicular to the bridge axis so as to coincide with the planned linear center line of the bridge having a straight section or a curved section, and the side form frame is the center in the bridge axis direction or the bridge axis direction of the lower surface of the side form mold. The protrusion provided in the vicinity of the center can be rotated to a groove provided in the outer edge portion of the bottom plate mold frame in the bridge axis direction central position or in the bridge axis direction center vicinity and substantially parallel to the bridge axis direction of the bottom mold frame. A plurality of one unit comprising the bottom formwork and the side formwork. A movable mold shoring, characterized in that form. Here, the center line in the bridge axis direction of the bottom stencil form is a line extending in the bridge axis direction at the center of the width in the direction perpendicular to the bridge axis of the bottom slab form.

The mobile formwork support of the present invention can obtain at least one of the following effects by means for solving the above-described problems.
<1> Since installation of the bottom plate formwork and the side formwork becomes extremely easy, the workability is improved and the construction period is shortened.
<2> Change of curve radius and sigmoid curve by having a function of sliding the bottom plate formwork and side formwork in the direction perpendicular to the bridge axis and rotating the side formwork on the bottom plate formwork. Can be easily accommodated.
<3> For each unit in which the side formwork is divided, it can be rotated at the center of the side formwork, so that a bridge corresponding to the designed curve radius can be constructed. Therefore, it is possible to realize a bridge construction with an excellent appearance.
<4> Since the bottom plate mold and the side mold can be easily adhered, the possibility of leakage of the mortar of the concrete becomes extremely low.

<1> Overall configuration of mobile formwork support The mobile formwork support 1 has girder and hand stretcher 5 installed on support bases 8 and 8 installed on a plurality of already constructed piers 7 and 7. The front portal structure 2 as viewed from the bridge axis direction is hung from the girder and the hand extender 5 at intervals in the bridge axis direction. The frame 2 includes a horizontal member 22 and left and right vertical members 21 and 21. In addition, the bottom stencil form 3 and the support 33 are attached so as to be rotatable about the axis in the bridge axis direction around the lower end of one of the vertical members 21 and 21 of the plurality of frames 2 and 2.

The mobile formwork supporter 1 of the present invention forms one unit of a bottom mold form 3 and a side form form 4 divided in the bridge axis direction so as to be slidable independently in the bridge axis direction. It is characterized by having prepared. Such a configuration is provided to cope with the construction of a bridge having a straight section and a curved section, in particular, a change in curve radius and a bridge having, for example, an S-shaped curved line.
Further, the side mold 4 is configured to be rotatably mounted on the bottom mold 3. This is because it is possible to construct the side wall (web) of the main girder corresponding to the change in the bridge alignment.

  The movable formwork supporter 1 is provided with a roof by installing corrugated sheets etc. on the horizontal members 22, 22 arranged in parallel in the bridge axis direction, and by installing a plate material on the outside of the vertical members 21, 21 arranged in parallel. A wall should be provided. In such a case, the mobile factory 11 is configured to move in a state suspended from the main girder, and the bridge girder 100 can be constructed without being influenced by the weather (see FIG. 1).

Further, the vertical member 21 has a slide member 23 provided at the lower end thereof so as to be extendable and contractible. In such a case, the bottom plate mold 3 and the support 33 are detachably attached to the tip of one slide member 23, and the attachment portion 6 of the bottom plate mold 3 is provided at the tip of the other slide member 23. Keep it. The attaching part 6 is provided with a rotating function, and is shaped so that the bottom plate formwork 3 (and the supporting work 33) can rotate around the attaching part 6 (see FIG. 2).
It is possible to cope with the crossing gradient of the bridge by adjusting the extension of the left and right slide members 23, 23.

The construction procedure for one cycle using the mobile formwork supporting work 1 (procedure focusing on the installation of the bottom formwork 3 and the side formwork 4 described below for curved bridges) is roughly as follows.
(1) Move the span of the movable formwork support 1 and install the support frame 8 and the moving factory 11 at predetermined positions in the bridge axis direction.
(2) Adjust the level of the bottom slab formwork 3 and the longitudinal transverse gradient.
(3) The position and direction of the side mold 4 are adjusted.
(4) The bottoms of the bottom plate mold 3 and the side mold 4 are fixed with, for example, a plurality of cotters. Here, the cotter is, for example, a split pin that is inserted into a tapered hole. By inserting the cotter into a plurality of holes provided in both mold frame constituent members, it is possible to easily and securely install both mold frames. .
(5) A gap closing mold 44 that closes the gap between the divided mold units is installed.
(6) The lower floor slab, the reinforcing bars of the side wall (web), and the sheath for PC steel (which may include PC steel) are arranged.
(7) Install while hanging the inner formwork.
(8) An upper floor slab and a PC steel sheath (which may include PC steel) are disposed.
(9) Place concrete.
(10) Carry out curing.
(11) Insert PC steel into the sheath.
(12) Tension the PC steel.
(13) The bottom plate mold 3, the side mold 4, and the gap closing mold 44 are removed.
(14) Remove the cotter.
(15) The bottom mold form 3 and the support work 33 are rotated, and the mobile formwork support work 1 is moved between the next spans while avoiding the bridge piers and mountain slopes that obstruct the movement of the mobile form work support work 1. .

<2> Bottom plate form frame One bottom plate form frame 3 is attached so as to be rotatable around the axis in the bridge axis direction around the lower end of one of the vertical members 21 and 21 of the plurality of frames 2 and 2. Here, the support 33 provided below the bottom plate form 3 can also rotate simultaneously with the bottom plate form 3 (see FIG. 2).
The bottom slab formwork 3 and the supporting work 33 are divided into a plurality of parts over the entire length of the mobile factory 11, and each divided unit is configured to be slidable in the direction perpendicular to the bridge axis. Here, the bridge axis direction center line of the bottom slab formwork 3 is slid in the direction perpendicular to the bridge axis so as to coincide with the planned linear center line of the bridge (bridge girder 100) having a straight section or a curved section.
The slide of the bottom plate formwork 3 and the support work 33 can be adjusted by using a bottom plate formwork jack 34 provided for each divided unit (see FIG. 3).
Further, a groove 31 is provided in an end side (outer edge portion 32) that is parallel to the bridge axis direction at the bridge axis direction center position (or near the bridge axis direction center position) of the bottom plate mold 3. The groove 31 is, for example, a V-shaped cut groove, and can be formed with a predetermined length in the direction perpendicular to the bridge axis at the outer edge portion 32. By installing a projection 43 provided on the lower surface of the side mold 4 described later in the groove 31, the projection 43 can slide in the horizontal direction and rotate in the groove 31. At the same time, the relative positions of the bottom plate mold 3 and the side mold 4 in the bridge axis direction and the direction perpendicular to the bridge axis can always be kept constant.
A plurality of bottom plate molds 3 having a predetermined width in the bridge axis direction are juxtaposed in the bridge axis direction, thereby constructing a bottom plate with a predetermined extension while performing slide adjustment according to the bridge alignment for each bottom plate mold 3. It becomes possible.

  Here, the bottom plate mold 3 can be rotated around the lower end of one vertical member 21 of the frame 2 by moving the bottom plate mold 3 (and the supporting work 33) to one side while rotating it. This is because it is possible to avoid the bridge pier 7 that can be an obstacle to the movement of the support work 1 during the next span movement. Further, when the bridge girder construction position is a mountain slope and close to the slope, it is possible to open and close the mountain slope and the bottom mold 3 without causing interference. Here, the one vertical member 21 described above is the vertical member 21 located on the valley side among the two vertical members 21 and 21 constituting the portal frame 2. In the conventional mobile formwork support (mobile formwork carriage a), there is a structure in which the half-plate bottom formwork b opens on both sides of the mobile formwork carriage a. In some cases, there is a possibility that the bottom slab form b opened in the middle may interfere with the tree 200 (see FIG. 5). In this case, it was necessary to cut the tree 200 in advance, and there was a concern about the influence on the surrounding environment with the construction.

Even when the bottom plate formwork 3 is opened and closed by only one of the vertical members 21 as in the present invention, in consideration of the case where the interference with the tree 200 cannot be avoided as described above, in the present invention, The attachment portion 6 of the bottom plate mold 3 can be slidable in the direction perpendicular to the bridge axis. That is, it is possible to avoid interference with the tree 200 and the like by opening the bottom plate formwork 3 to the valley side in a state where the valley-side attachment portion 6 is slid to the valley side perpendicular to the bridge axis by a predetermined length.

<3> Side Form Form The side form form 4 is, for example, a form form used when building a PC box girder bridge, and includes a side wall frame 41 and a bottom frame (an overhang bottom frame 42) of both side overhang portions of the upper floor slab. . The plate lengths (length in the bridge axis direction) of the side wall frame 41 and the overhanging bottom frame 42 are determined according to the planar alignment in the bridge axis direction and the like. When the meandering is relatively intense, the plate length is set short.
When the side wall frame 41 has a predetermined tilt angle and the bottom of the overhanging portion of the upper floor slab has a predetermined taper angle, the side mold 4 configured to have such a tilt angle and a taper angle is manufactured.
In the present invention, in order to adopt a configuration in which a plurality of units of the bottom plate mold 3 and the side mold 4 divided in the bridge axis direction of the movable mold support 1 are arranged side by side, Are formed with side molds 4 and 4 for constructing the left and right side walls constituting the bridge girder 100.

  A protrusion 43 is provided at the center of the bridge axis direction or near the center of the bridge axis direction on the lower surface of the side mold 4, and the protrusion 43 is the center position in the bridge axis direction of the bottom mold form 3 or the position near the center of the bridge axis direction. The protrusion 43 is dropped into the groove 31 provided in the outer edge portion 32 parallel (or substantially parallel) to the bridge axis direction of the bottom plate mold 3 (see FIG. 4). Further, in order to allow the side mold 4 to slide and rotate on the bottom mold 3, for example, the two side mold jacks 45, 45 are supported by the support rod 46 with the projection 43 interposed between the one side mold 4. , 46 should be installed. The side mold 4 can be slid horizontally by adjusting the strokes of the two side mold jacks 45, 45 to the same extent, and the side mold jacks 45, 45 can be adjusted by changing the stroke amount according to the bridge alignment. It can be rotated around the projection 43 together with the horizontal slide.

When the protrusion 43 described above is dropped into the groove 31 and installed, the protrusion 43 and the groove 31 are preferably formed so that the protrusion 43 enters the deepest part of the groove 31.
By adopting a configuration in which the groove 31 is provided in the outer edge portion 32 of the bottom plate mold 3, the side mold 4 can keep the relative positions of both molds on the bottom plate 3 almost constant.
After the position and direction of the side mold 4 are adjusted on the bottom mold 3, both molds are inserted by inserting cotters (split pins) into a plurality of pin holes provided in the components of the side mold 4 and the bottom mold 3. The frame should be tightly fixed (not shown).

The perspective view which showed the mobile formwork support work of this invention. It is the figure explaining the condition which is carrying out the rotational demolding of the bottom formwork, Comprising: The AA arrow line view of FIG. The front view which showed the jack for bottom plate formwork slide, the side formwork slide, and the jack for rotation. The perspective view explaining the condition which has installed the side surface formwork, rotating a side surface formwork. The front view which showed the conventional mobile formwork trolley | bogie.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mobile formwork support work 3 ... Bottom plate formwork 31 ... Groove 4 ... Side face formwork 43 ... Projection

Claims (1)

A mobile formwork support used when building bridge girders,
The movable formwork supporting work is formed such that one unit of the bottom formwork and side face formwork divided in the bridge axis direction can be slid in the direction perpendicular to the bridge axis, respectively.
The bottom slab formwork is slidable in a direction perpendicular to the bridge axis so that the bridge axis direction center line of the bottom slab form form coincides with a planned linear center line of a bridge having a straight section or a curved section,
The side mold has a protrusion provided at the center in the bridge axis direction or in the vicinity of the center in the bridge axis direction on the lower surface of the side mold. And it is rotatably installed in a groove provided in an outer edge portion substantially parallel to the bridge axis direction of the bottom plate formwork,
It comprises a plurality of one unit consisting of the bottom plate formwork and the side formwork,
Mobile formwork support.

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