JP6081843B2 - Formwork and concrete placement method - Google Patents

Description

  The present invention relates to a formwork and a concrete placing method using the same.

  When fixing the fall prevention device to the side of the lower structure such as the abutment or pier of the existing bridge, post-installed anchor bolts are installed on the side of the lower structure. However, the design value for the bridge displacement limit may not be ensured only by directly fixing the falling bridge prevention device to the side surface of the lower structure. In this case, concrete is added to the side surface of the lower structure, and the falling bridge prevention device is fixed to the threaded portion of the anchor bolt protruding from the additional hitting portion.

  When performing such additional hitting, generally, a mold made of a plywood having a through hole formed in accordance with the position of the anchor bolt is used. Then, in a state where the anchor bolt is inserted into the through hole, the formwork is installed at an interval from the side surface of the lower structure by the thickness of the hitting portion, and concrete is placed. The diameter of the through hole of the mold frame needs to be larger than the diameter of the anchor bolt by an allowance considering the positional deviation of the anchor bolt.

  In Patent Document 1, when a reinforced concrete wall and a ridge are integrally formed, a reinforcing bar serving as a base of the heel is arranged in the wall, and a wall portion is formed around the base of the heel. It is described that a frame material made of a material that can be easily crushed, such as an expandable resin, is attached so that no concrete enters.

  Patent Document 2 describes that a hard foamed resin processed material is used as a mold of a leg portion of a reverse-stripped concrete column. By inserting a reinforcing bar into the hole formed in the mold, no concrete is placed around the reinforcing bar, and the reinforcing bar is protected by the foaming resin, so that it is difficult to cause fouling during operation.

Japanese Patent No. 3280357 Japanese Patent Laid-Open No. 08-144522

  However, when using a formwork made of plywood with through-holes, the mortar part of the concrete flows out from the gap between the through-holes of the formwork and the anchor bolts, and the roots of the projecting parts of the anchor bolts and the additional striking parts The mortar adheres to the surface. Since the mortar portion fixed in this way becomes a hindrance when fixing the falling bridge prevention device, it is necessary to remove it.

  Further, in the region where the through holes of the mold form are densely present, the anchor bolt protruding from the through hole becomes an obstacle, and the support work cannot be installed at an appropriate position, and the mold form may not be supported properly. .

  In addition, the molds described in Patent Documents 1 and 2 are all the molds of the joining part, and the surface of the leading part need not be smooth.

  Furthermore, in the technique described in Patent Document 1, it is an anchor material that causes a part of the casing to be recessed, and does not protrude the reinforcing bar from the front surface of the casing. Moreover, since it is a new installation part, arrangement | positioning of a reinforcing bar is free and there is no restriction | limiting in arrangement | positioning of a support work. And in the technique of the said patent document 2, a reinforcing bar only contact | abuts to a floor surface, There is no restriction | limiting in the arrangement | positioning of a support work.

  In view of the above points, the present invention is used when a concrete portion is struck by projecting a threaded portion at the tip of an anchor bolt by a preset length, and the mortar content of the concrete does not flow out. It is an object of the present invention to provide a formwork that can be supported on a wall and a concrete placement method using the formwork.

  The formwork of the present invention is a formwork for forming an additional striking portion in which a screw portion of an anchor bolt embedded in the lower structure protrudes by striking concrete on the side surface of the lower structure of the bridge, The foamable resin comprising: a foamable resin material made of a foamable resin and spaced from a side surface of the lower structure; and an outer surface material arranged outside the foamable resin material and supported by a support work. The material is formed with an insertion hole having a diameter smaller than the diameter of the anchor bolt in accordance with the position of the anchor bolt, and a length portion set in advance from the tip of the anchor bolt is disposed in the insertion hole. It is characterized by that.

  According to the mold of the present invention, the diameter of the insertion hole into which the anchor bolt of the foamable resin material is inserted is smaller than the diameter of the anchor bolt. For this reason, when the anchor bolt is inserted into the insertion hole, the anchor bolt advances while expanding the insertion hole. Therefore, there is no gap between the anchor bolt and the insertion hole, and the mortar portion does not flow out when the concrete is placed, so that it is not necessary to remove the excessive fixing of the mortar.

  Moreover, since the outer surface material is located outside the anchor bolt, it is not necessary to form an insertion hole. Therefore, the outer surface material can be supported by the support work regardless of the arrangement of the anchor bolts, so that the formwork can be appropriately supported by the support work.

  In addition, the length set in advance from the tip of the anchor bolt may be longer than the length required for the work after dismantling the formwork. For example, when fixing the falling bridge prevention device with a nut, the falling bridge prevention device is arranged. In addition, it is sufficient that the length of the support plate and the nut can be surely set.

  In the mold of the present invention, it is preferable that the foaming resin material further includes a smoothing material disposed on a surface facing the side surface of the lower structure and having a smooth surface facing the side surface of the lower structure.

  In this case, the surface of the additional hitting portion can be smoothed without processing the surface facing the side surface of the lower structure of the foamable resin material.

The method of placing concrete according to the present invention is a method of placing concrete on the side surface of the lower structure of a bridge, and placing concrete that forms an additional portion where a threaded portion of an anchor bolt embedded in the lower structure protrudes. In accordance with the position of the anchor bolt, a step of forming an insertion hole having a diameter smaller than the diameter of the anchor bolt in a foamable resin material made of a foamable resin, and presetting from the tip of the anchor bolt A step of installing the foamable resin material at a distance from a side surface of the lower structure, and a step of installing an outer surface material on the outside of the foamable resin material so that the length portion thus formed is disposed in the insertion hole. When, characterized in that it comprises the step of pouring concrete between the steps of supporting Ri by the outer members to shoring, the side surface of the lower structure and said expandable resin material

  According to the concrete placing method of the present invention, the diameter of the insertion hole through which the anchor bolt of the foamable resin material is inserted is smaller than the diameter of the anchor bolt. For this reason, when the anchor bolt is inserted into the insertion hole, the anchor bolt advances while expanding the insertion hole. Therefore, there is no gap between the anchor bolt and the insertion hole, and the mortar portion does not flow out when the concrete is placed, so that it is not necessary to remove the excessive fixing of the mortar.

  Moreover, since the outer surface material is located outside the anchor bolt, it is not necessary to form a hole. Therefore, the outer surface material can be supported by the support work regardless of the arrangement of the anchor bolts, so that the formwork can be appropriately supported by the support work.

  In the concrete placement method of the present invention, the foamable resin material is pressed against the tip of the anchor bolt to form a recess in the surface of the foamable resin material, which is aligned with the position of the anchor bolt. It is preferable to form the insertion hole in

  In this case, an insertion hole can be formed in the foamable resin material accurately and easily in accordance with the position of the anchor bolt without requiring special equipment.

  The concrete placement method of the present invention preferably further includes a step of providing a protective material around the threaded portion of the anchor bolt.

  In this case, the concrete can be prevented from adhering to the threaded portion of the anchor bolt when the concrete is placed.

Sectional drawing which shows the state which formed the additional striking part using the formwork which concerns on embodiment of this invention. Sectional drawing which shows the state which installed the fallen bridge prevention apparatus in the additional striking part.

  A form 10 according to an embodiment of the present invention will be described with reference to FIG.

  When the formwork 10 is formed on the side surface of the lower structure 1 such as an abutment or a pier of an existing bridge to form the increased hitting portion 3 from which the screw portion 2a of the anchor bolt 2 embedded in the lower structure 1 protrudes. used.

  The anchor bolt 2 has a base end portion embedded in the lower structure 1 and a tip screw portion 2 a protruding from the side surface of the lower structure 1. The anchor bolts 2 are provided in the existing lower structure 1 by post-construction, and are installed avoiding the reinforcing bars arranged inside the lower structure 1, and thus are not regularly arranged.

  The mold 10 includes a foamable resin material 11, an outer surface material 12, and a smooth material 13. The foamable resin material 11 and the outer surface material 12, and the foamable resin material 11 and the smoothing material 13 may or may not be bonded with an adhesive.

  The foamable resin material 11 is disposed at a distance from the side surface of the existing bridge lower structure 1 and is made of a foamable resin. The foamable resin is a synthetic resin containing bubbles, and the foamable resin material 11 is made of foamed polystyrene, polyurethane foam, styrofoam, polypropylene foam, urea resin foam, or the like. In addition, the foamable resin material 11 may be a plate material made of a foamable resin, for example, a laminate of a plurality of foamed polystyrene foams.

  In the foamable resin material 11, an insertion hole 11 a is formed in accordance with the position of the anchor bolt 2, and the diameter of the insertion hole 11 a is smaller than the diameter of the anchor bolt 2. The insertion hole 11a may be a through hole or not a through hole.

  A length portion set in advance from the tip of the anchor bolt 2 is positioned in the insertion hole 11a. The length of the anchor bolt 2 in the insertion hole 11a may be the same as that of the screw part 2a or may be shorter than the screw part 2a. When the tip position differs depending on the anchor bolt 2, the thickness (horizontal width) of the foamable resin material 11 is adjusted so that the tips of all anchor bolts 2 are arranged in the insertion holes 11a, The outer surface of the foamable resin material 11 is a vertical surface.

  The outer surface material 12 is arranged on the outer side of the foamable resin material 11 so that there is no step or unevenness on the surface, and the outer surface 12 is supported by the support work 21. The outer surface material 12 is a plate material made of wood such as plywood, and no hole is formed. In FIG. 1, a pipe end thickness is shown as the support work 21. The outside of the outer surface material 12 is preferably flat so that the support work 21 can be easily installed. If there is a step on the surface of the additional striking portion 3, the outer surface material 12 is adjusted by the thickness of the foamable resin material 11.

  The smooth material 13 is a material that is disposed inside the foamable resin material 11 and has a smooth surface made of an ultra-thin decorative board or a tape material. If the surface of the additional striking portion 3 does not have to be smooth, the smoothing material 13 may be omitted. Also, the smooth material 13 may be omitted when the surface of the foamable resin material 11 that faces the side surface of the lower structure 1 is processed smoothly.

  A through hole 13 a is formed in the smooth material 13 in accordance with the position of the anchor bolt 2. The diameter of the through hole 13 a formed in the smoothing material 13 is larger than the diameter of the anchor bolt 2.

  Hereinafter, a concrete placing method according to an embodiment of the present invention will be described with reference to FIG.

  First, according to the position of the anchor bolt 2, a first step of forming the through hole 13 a in the smoothing material 13 is performed.

  Next, the 2nd process of forming the insertion hole 11a which has a smaller diameter than the diameter of the anchor bolt 2 in the foaming resin material 11 is performed.

  In this second step, the foamable resin material 11 is pressed against the tip of the anchor bolt 2 to form a recess in the surface of the foamable resin material 11 at the position of the anchor bolt 2, and an insertion hole is formed at the position of this recess. 11a may be formed. Thereby, the insertion hole 11a can be formed accurately and easily according to the position of the anchor bolt 2 without requiring special equipment.

  Next, the 3rd process of providing the protective material 22 which prevents adhesion of concrete around the thread part 2a of the anchor bolt 2 is performed. The order of the first to third steps is not limited. For example, the through hole 13a may be formed in the smoothing material 13 in accordance with the insertion hole 11a formed in the second step.

  Next, a fourth step is performed in which the anchor bolt 2 is inserted into the through-hole 13 a and the smoothing material 13 is installed at a predetermined interval from the side surface of the lower structure 1. This interval is increased to the thickness of the hitting portion 3.

  Next, the anchor bolt 2 is inserted into the insertion hole 11a, and the foamable resin material 11 is placed outside the smoothing material 13 so that a preset length from the tip of the anchor bolt 2 is located in the insertion hole 11a. A fifth step of installing in contact is performed. Since the diameter of the insertion hole 11a of the foamable resin material 11 is smaller than the diameter of the anchor bolt 2, the anchor bolt 2 is inserted into the insertion hole 11a while expanding the insertion hole 11a. When the smoothing material 13 is omitted, the foamable resin material 11 is installed with a predetermined interval from the side surface of the lower structure 1. In this case, this interval increases and becomes the thickness of the hitting portion 3.

  Next, a sixth step of installing the outer surface material 12 outside the foamable resin material 11 is performed.

  Next, a seventh step of supporting the outer surface material 12 with the support work 21 is performed.

  Next, an eighth step of placing concrete between the side surface of the lower structure 1 and the smoothing material 13 is performed. A reinforcing bar may be arranged between the side surface of the lower structure 1 and the smoothing material 13.

  Finally, after the concrete is cured, a ninth step of removing the support work 21, the outer surface material 12, the foamable resin material 11, and the smoothing material 13 is performed. Thereby, the additional hit | damage part 3 is formed in the part in which the concrete was laid in the 8th process. A part of the anchor bolt 2 is embedded in the increased hitting portion 3, but the screw portion 2 a is not embedded in the increased hitting portion 3. However, the threaded portion 2a of the anchor bolt 2 only needs to protrude from the increased striking portion 3 by a necessary length, and a part thereof may be embedded in the increased striking portion 3.

  After that, as shown in FIG. 2, the anchor plate 2 is inserted into the through hole of the fall-bridge prevention device 31 and the fall-bridge prevention device 31 is in contact with the outer surface of the striking portion 3 while the fixing plate 32 is attached. Then, the nut 33 is screwed into the threaded portion 2a of the anchor bolt 2. Thereby, the falling bridge prevention device 31 is fixed to the side surface of the additional hitting portion 3. The falling bridge prevention device 31 is disposed on the bridge girder 4 and is disposed with a predetermined gap between the displacement limiting protrusion and a not-shown illustration.

  In addition, since the position of the anchor bolt 2 varies depending on the lower structure 1, the foamable resin material 11 and the smoothing material 13 cannot be reused, but the outer surface material 12 can also be reused.

  As described above, according to the embodiment of the present invention, the insertion hole 11a having a diameter smaller than the diameter of the anchor bolt 2 is formed in the foamable resin material 11, and the anchor is then expanded while the insertion hole 11a is expanded. The bolt 2 is inserted into the insertion hole 11a.

  Therefore, there is no gap between the anchor bolt 2 and the insertion hole 11a, and the mortar content does not flow out when concrete is placed. Therefore, since the mortar is not fixed on the root portion of the anchor bolt 2 protruding from the additional striking portion 3, the surface of the additional striking portion 3, or the like, it is not necessary to remove the mortar.

  Moreover, no hole is formed in the outer surface material 12, and the support work 21 can be installed regardless of the irregular arrangement of the anchor bolts 2. Therefore, the formwork 10 can be appropriately supported by the support work 21.

  In addition, the foamable resin material 11 can withstand the pressure at the time of placing concrete, but has lower strength and rigidity than the plywood. For this reason, when the foamable resin material 11 is directly supported by the support work 21, the supported portion may be depressed due to the support pressure, and the surface of the additional striking portion 3 may be uneven. Therefore, in the present embodiment, the outer surface material 12 is installed between the foamable resin material 11 and the support work 21, and the support pressure from the support work 21 is dispersed, so that the foaming resin material 11 is depressed. Deformation can be prevented.

  In addition, the foamable resin is strong against compression but weak against bending. Therefore, in this embodiment, the outer surface material 12 that receives bending stress is installed outside the foamable resin material 11 to reinforce the mold 10.

  In addition, the foamable resin has a high heat retention and moisture retention effect and is suitable for curing concrete.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this.

  DESCRIPTION OF SYMBOLS 1 ... Bridge substructure, 2 ... Anchor bolt, 2a ... Screw part, 3 ... Additional punching part, 10 ... Formwork, 11 ... Foamable resin material, 11a ... Insertion hole, 12 ... Outer surface material, 13 ... Smooth material, 13a ... through-hole, 21 ... support work, 22 ... protective material, 31 ... fall-bridge prevention device.

Claims (5)

A formwork for forming an additional striking portion in which a screw portion of an anchor bolt embedded in the lower structure is projected by striking concrete on the side surface of the lower structure of the bridge,
A foamable resin material disposed at a distance from a side surface of the lower structure and made of a foamable resin;
An outer surface material disposed outside the foamable resin material and supported by a support work;
In the foamable resin material, an insertion hole having a diameter smaller than the diameter of the anchor bolt is formed in accordance with the position of the anchor bolt.
A formwork, wherein a length portion set in advance from a tip of the anchor bolt is disposed in the insertion hole.   2. The mold according to claim 1, further comprising a smoothing material that is disposed on a surface of the foamable resin material that faces the side surface of the lower structure and has a smooth surface that faces the side surface of the lower structure. frame. It is a method of placing concrete on the side surface of the lower structure of the bridge and placing concrete that forms an additional striking portion in which the threaded portion of the anchor bolt embedded in the lower structure protrudes,
A step of forming an insertion hole having a diameter smaller than the diameter of the anchor bolt in the foamable resin material made of a foamable resin in accordance with the position of the anchor bolt;
Installing the foamable resin material at a distance from the side surface of the lower structure so that a length portion set in advance from the tip of the anchor bolt is disposed in the insertion hole;
Installing an outer surface material outside the foamable resin material;
A step of support Ri by the shoring the outer surface material,
A method for placing concrete, comprising a step of placing concrete between a side surface of the lower structure and the foamable resin material.   The foamable resin material is pressed against the tip of the anchor bolt to form a recess in accordance with the position of the anchor bolt on the surface of the foamable resin material, and the insertion hole is formed at the position of the recess. The concrete placing method according to claim 3.   The method for placing concrete according to claim 3 or 4, further comprising a step of providing a protective material around the threaded portion of the anchor bolt.

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