JP2017008563A - Pc board formwork material and foundation construction method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a PC board formwork material that can sufficiently endure earth pressure by providing a longitudinal groove in a precast concrete board (PC board) to fit the longitudinal grooves of adjacent PC boards together, and is used for pillar foundation construction of a building, and provide a construction method using the same.SOLUTION: A longitudinal groove of the same direction or vertically different directions is provided in both end sides of a PC board 14, and the longitudinal grooves provided in the adjacent PC boards 14 is fitted together and a formwork 13 is assembled. The size of the formwork 13 configured by the PC board 14 is about 2.6 m to 4 m in width and 1.2 m to 1.5 m in height. The depth of the longitudinal groove may be slightly larger than 1/2 of a height dimension.SELECTED DRAWING: Figure 6

Description

  In constructing an independent foundation part of a building, etc., the present invention newly develops a precast concrete plate (PC version) discarded frame material, and uses this PC version discarded frame material in a short period of time with other contractors. It is related with the construction method which can construct | assemble a building foundation only by a PC version builder, without performing cooperation.

When constructing the foundation of a pillar of a building, the conventional construction method is to first dig up the ground located in the foundation part and if necessary according to the size of the building, the soil quality, etc. Driving piles. Then, the crushed stones or crushed stones are laid on the bottom ground of the dug groove, and the base surface is formed by compacting with a hammer such as a runner and driving the concrete to a thickness of about 10 cm. .
After that, a frame is formed on this base surface using a wooden formwork made of veneer plywood and piers or a steel formwork, a reinforcing bar is built inside, and concrete is placed in the formwork to form the foundation. Is building. After casting the concrete, the mold was removed from the mold, and then backfilled with earth and sand dug up around the concrete foundation.
The foundation parts of the columns are connected by underground beams.

However, in the construction method generally used in the past, it is necessary to remove the mold by removing the mold after assembling the mold and placing the concrete, and assembling and removing the mold There is a disadvantage that a large space for excavation is required, and the area to be excavated becomes large and the amount of earth and sand discharged is increased. Moreover, it was necessary to temporarily store the excavated earth and sand temporarily in another place, and the space was necessary. Furthermore, the construction of placing concrete after installing the mold and backfilling after demolding has the disadvantage that the number of processes increases and the construction period is prolonged.

Therefore, in recent years, as described in Patent Document 1 or 2, after installing the formwork, the surrounding area is backfilled, and concrete is placed and the formwork is left buried in the soil as it is. Formwork methods have been developed.

The technique of patent document 1 shows the abandonment formwork method which constructs | assembles the cloth foundation erected in T shape from a foundation surface with a precast concrete plate (PC version). Notches are provided on both ends of the PC plate, embedded nuts are planted on the notch end faces, and the adjacent PC plates are connected and fixed together using special L-shaped metal fittings and connecting bolts. I am doing so. After the connection, the PC plate is backfilled with earth and sand dug up the grooves on both sides, and a wooden building is constructed on the upper end surface of the fabric foundation.
In addition, since the PC plate itself constitutes the fabric foundation, the PC plate itself was used as a formwork material and concrete was not placed.

The technique of patent document 2 is a technique in the case of constructing an underground beam using a keystone plate (steel formwork of a hot dip galvanized copper plate). First, the excavation groove having the same width as that of the underground beam is dug up. And the crushed stones or crushed stones are laid side by side on the bottom side of the excavation groove, and the crushed stone having a thickness of about 5 to 10 cm is placed. Next, support bars are erected in the excavation groove almost vertically at intervals along both sides, and steel plates such as keystone plates as a formwork material are supported on these support bars. A pair of opposing metal molds is provided. After that, slab reinforcing bars are placed on the upper surface side of the area surrounded by underground beams, and underground beam reinforcing bars are placed inside the underground beams, and these slab reinforcing bars and underground beam reinforcing bars The concrete is assembled integrally, and concrete is cast in a series from the slab to the steel plate formwork.

Conventionally, the technique shown in FIG. 9 is known as a method for constructing a pillar foundation using a keystone plate. In this prior art, an L-shaped angle member 2 or a runner member is fixed at a predetermined position on the discarded surface 1 of the bottom surface of the excavated groove, and a continuous rectangular wave-shaped keystone plate 3 is erected on the outer peripheral surface side. The L-shaped angle member 4 is fixed to the upper end surface side by welding. The L-shaped joint 5 is welded in the vertical direction at the corner where the adjacent keystone plates 3 come into contact with each other. Further, in order to increase the overall rigidity, a reinforcing connecting member (crossed) 6 is welded to the upper end surface of the corner portion. This is because if the rigidity is not increased, the surrounding earth pressure during backfilling cannot be withstood.
In addition, the opening 7 provided in the upper center part of a pair of opposing keystone plates 3 and 3 is for connecting with an underground beam.

JP-A-8-296239 Japanese Patent No. 2629482

In the technique shown in Patent Document 1, since the PC plate-discarding formwork is left as it is buried in the soil, it is not necessary to remove the mold, and the construction period can be shortened. There is a problem that it cannot be used as it is as a construction.
The foundation of the building pillar depends on the size of the building, etc., but the length of one side of the rectangular body is usually 2m to 3m and the height is 1.2m to 1.5m. After the formation, when the surrounding excavation groove is backfilled with the earth and sand that has been dug up, a considerably large earth pressure acts on the PC plate formwork material. For this reason, when the PC plate formwork members are connected using dedicated L-shaped metal fittings and bolts, the stress of earth pressure acting on the entire PC plate formwork material concentrates on the connecting portion, and the L-type metal fittings and bolt portions The PC plate formwork material was damaged, and the PC plate formwork material fell to the inside, which was the space area of the foundation part where concrete had to be placed, and the formwork could not be assembled.

  Moreover, in the construction method of this patent document 1, a special L-shaped metal fitting must be manufactured and prepared, a notch having a specific shape is formed in the PC plate mold frame material, and bolts are fastened to the notch portion. It is necessary to plant embedded nuts, and extra steps such as mounting brackets and fastening bolts are required when assembling PC formwork materials, which increases the number of processing and assembly processes as a whole, and increases costs. It was also the cause of.

Moreover, in the technique shown in Patent Document 2 etc., a reinforcing bar is inserted into the soil at predetermined intervals in portions along both sides of the excavation groove, and a keystone plate is arranged by leaning on the reinforcing bar. It is a discarded formwork for pouring concrete.
However, such a technique is used as a formwork material for a large-capacity columnar foundation with a side of a rectangular body of 2 m to 3 m and a height of 1.2 m to 1.5 m even if it is normal. This was not possible because of the large earth pressure.

Therefore, when using a keystone plate, it is necessary to weld the upper and lower end surfaces of the keystone plate 3 with L-shaped angle members or runner members 2 having a U-shaped cross section, as shown in the prior art of FIG. In addition, the L-joint 5 is welded to the corner where the keystone plates 3 come into contact with each other, and the connecting material (diagonal) 6 is welded to the corner on the upper end side to increase the overall rigidity. I had to.
Therefore, in the prior art shown in FIG. 9, a welding worker is required in addition to the construction worker, and the cooperative work between the two is indispensable, and the construction worker cannot assemble the formwork alone. There was a problem and an accident based on inadequate cooperation. In addition to the mold material of the keystone plate 3, additional parts such as L-shaped angle or runner members 2, 4, L-shaped joint 5, connecting material (diagonal crossing) 6 are necessary. There is also a problem that management requires labor and cost, and the work becomes complicated. Furthermore, it is a metal formwork material and has a problem that it corrodes due to aging.

Therefore, the present invention is an improvement and removal in view of the above-mentioned conventional problems, in which a vertical groove is provided in a precast concrete plate (PC plate) and the vertical grooves of adjacent precast concrete plates are fitted to each other. By doing so, we intend to provide a PC plate formwork material for column foundation construction that can sufficiently withstand earth pressure, and a construction method using this.

The means of claim 1 adopted by the present invention in order to solve the above-mentioned problems is that a longitudinal groove in the same direction is provided on both end sides of a rectangular precast concrete plate, and the longitudinal groove is the adjacent precast concrete plate. It is a PC formwork material characterized in that it can be fitted into a longitudinal groove provided in the plate.

The means of claim 2 adopted by the present invention in order to solve the above problems is provided with an upward vertical groove on one end side of a rectangular precast concrete plate and a downward vertical groove on the other end side. Each of the vertical grooves in the vertical direction can be fitted with the vertical grooves in the vertical direction provided in the adjacent precast concrete plate.

  In order to solve the above-mentioned problem, the means of claim 3 adopted by the present invention is to cut away a portion from the upper end surface or the lower end surface to the middle of the longitudinal groove in the region between the longitudinal groove and the end. The PC formwork material according to claim 1 or 2, which is used.

  The means of claim 4 adopted by the present invention in order to solve the above-mentioned problem is that a concave portion for connection with the formwork for underground beam is formed in the middle of the upper end surface of the precast concrete plate toward the middle of the lower end side. The PC plate form material according to any one of claims 1 to 3.

  The means of claim 5 adopted by the present invention to solve the above problems is to dig up the ground at the position where the foundation of the building is constructed, install a base surface on the bottom surface of the base, etc., and upward on the base surface A precast concrete plate with a vertical groove is installed, and the downward vertical groove of another precast concrete plate is fitted to the upward vertical groove of the precast concrete plate, and the adjacent precast concrete plates are combined. Combine and form a formwork with an arbitrary polygonal plane shape with a plurality of precast concrete slabs, backfill with earth and sand dug up around the formwork, and cast concrete into the formwork to form the foundation of the building This is a construction method for building a foundation using a PC formwork material characterized in that it is constructed.

  In the invention of claim 1, longitudinal grooves in the same direction are provided on both ends of the rectangular precast concrete plate. When constructing the foundation of a building, it is only necessary to fit the vertical grooves provided in the adjacent precast concrete slab. However, since the vertical groove is provided in the same direction on both ends of the precast concrete plate, two precast concrete plates with the vertical groove facing upward are arranged facing each other at a predetermined interval, and the precast concrete plate is in that state. It is necessary to fit them with the vertical grooves facing downward.

In the case of the PC formwork material of this claim 1, since welding work is unnecessary, it is possible to build the formwork only by the PC version builder, resulting from poor cooperation between different traders. It is possible to prevent accidents. It is also possible to reduce the burden on construction workers by simplifying the assembly work itself.

  In the invention of claim 2, an upward vertical groove is provided on one end side of the rectangular precast concrete plate, and a downward vertical groove is provided on the other end side. Forming the formwork by fitting the longitudinal grooves together is the same as in the case of claim 1. In the PC plate form material of claim 2, by combining with the PC plate form material of claim 1, it is not necessary to prepare two pairs of precast concrete plates at first, but one by one. It can be assembled by fitting the vertical grooves between each other. Thereby, the number of workers can be reduced.

  In the invention of claim 3, in a region between the longitudinal groove and the end, a portion from the upper end surface or the lower end surface to the middle of the longitudinal groove is cut out. This excised part does not function as an opposing means such as earth pressure, and is an essentially unnecessary part. By cutting, it is possible to reduce the material cost.

  In the invention of claim 4, the underground beam is provided in the foundation portion of the building, and the reinforcement of the foundation portion and the reinforcement of the underground beam are assembled together, and concrete is also cast. It is possible to perform the foundation part and the underground beam at the same time.

  The invention of claim 5 is a construction method until the foundation part formwork is actually built using the PC plate form material of claim 1 to 4 and concrete is placed. A precast concrete plate with an upward vertical groove formed on the base surface of the foundation of the building is installed, and the downward vertical groove of another precast concrete plate is fitted into the upward vertical groove so that the adjacent precast concrete Combine and combine the plates. By repeating this, a formwork having an arbitrary polygonal plane shape is built with a plurality of precast concrete plates.

And backfill with earth and sand dug up around the formwork. The earth pressure at this time is transmitted to the adjacent precast concrete plate and dispersed, and the earth pressure in the opposite direction acts from the opposing precast concrete plate and cancels each other. There is no such thing as collapse or loss.
Moreover, the pressure of the concrete poured into the foundation formwork built with the precast concrete plate acts on each precast concrete plate, but it is enough because the outer periphery of each precast concrete plate is filled with earth and sand that has been backfilled. It is backed up and there is no problem.

In addition, since the precast concrete plate can be built and the earth and sand dug up can be backfilled almost simultaneously, the time for temporarily placing the earth and sand dug up can be shortened. In addition, since the precast concrete formwork material is embedded in the soil as it is, there is no need for a large space for erection and demolding work, and the amount of earth and sand that is dug up for the foundation construction must be reduced. Can do. It is possible to shorten the work period and reduce the work load.
Further, since no metal material is used, there is no problem of corrosion. Furthermore, since a precast concrete plate is interposed around the concrete foundation portion, it can function as a protective layer for preventing the neutralization of the concrete in the foundation portion and the corrosion of the foundation rebar.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a PC formwork frame according to an embodiment of the present invention, in which FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. (B) is provided with vertical grooves in the vertical direction. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a partially cut-off type PC formwork frame according to an embodiment of the present invention. FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. It is a perspective view at the time of providing this vertical groove. It is a perspective view which concerns on one embodiment of this invention and shows a 1st erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 2nd erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 3rd erection process. It is a perspective view which concerns on one embodiment of this invention, and shows the whole state in which construction of the PC plate formwork was completed. It concerns on one embodiment of this invention, and is the longitudinal cross-section of the basic part of the state which the erection of the PC formwork was completed. The longitudinal section which shows the whole foundation part which shows the state which is related to one embodiment of this invention, and concrete is laid, a pillar type | mold is formed, and the steel frame is built after the completion of construction of a PC formwork FIG. It is a perspective view which shows the whole steel formwork for demonstrating the construction method of the foundation part using the conventional keystone plate.

  The configuration of the present invention will be described below based on an embodiment shown in the drawings. 1 (A) and 1 (B) in FIG. 1 and FIG. 2 (A) and FIG. 2 (B) in FIG. 2 are cases in which the formwork materials 10, 11, 12, and 13 are made of a precast concrete plate (PC plate). It is a perspective view which shows an example. These PC plate form materials 10 to 13 generally have a width of 2.6 m to 4 m and a height of 1 although it depends on the size of the concrete foundation designed according to the size of the building to be constructed. .About 2 m to 1.5 m. This is a case where the length of one side of the concrete foundation corresponds to about 2 m to 3 m and the height is about 1.2 m to 1.5 m. As for the said PC type | mold frame materials 10-13, the reinforcing bar is arranged inside, and thickness is about 50 mm-150 mm. In the experiment, 60 mm was sufficient when constructing the foundation of a rectangular column having a side length of 2 m and a height of 1.2 m.

  A PC formwork material 10 shown in FIG. 1A is provided with longitudinal grooves 15 and 16 in the same direction (upward in the drawing) on both end sides of a rectangular precast concrete plate 14. The depth of the longitudinal grooves 15 and 16 only needs to be slightly larger than ½ of the height dimension. Moreover, the position of the vertical grooves 15 and 16 should just be a position where the dimension between the vertical grooves 15 and 16 corresponds to the length of one side of the concrete foundation to be constructed, and about 200 mm to 300 mm from the left and right side end faces, It is appropriate to enter the inside. The width of the longitudinal grooves 15 and 16 may be a little larger than the thickness of the precast concrete plate.

  The PC formwork material 11 shown in FIG. 1B is a case where an upward vertical groove 15a is formed near the left end surface and a downward vertical groove 17 is formed near the right end surface. Other configurations are the same as those of the PC plate mold material 10 shown in FIG.

  The PC plate formwork material 12 shown in FIG. 2A is a region outside the longitudinal grooves 15 and 16 of the PC plate formwork material 10 shown in FIG. A part of a region in the middle from the upper end surface to the groove bottoms of the vertical grooves 15 and 16 is cut out. The excised part is not a part having a special function as a formwork material, so it was decided not to produce it from the beginning to contribute to reducing the material cost. Further, by cutting, there is also an advantage that the vertical grooves can be easily fitted together when assembling the PC plate form material described later.

  The PC plate formwork 13 shown in FIG. 2B is the outer side of the longitudinal groove 15a of the PC plate formwork 11 shown in FIG. A part of a region in the middle from the vertical groove 15a to the groove bottom of the vertical groove 15a, and a region outside the vertical groove 17 and from the lower end surface of the precast concrete plate 14 to the groove bottom of the vertical groove 17 respectively. A part of the middle region is excised. About the effect of a cutting part, it is the same as that of the case of the PC plate mold frame material 12 shown to the figure (A) of the said FIG.

  Next, referring to FIG. 3 to FIG. 7, the formwork in the case of constructing the concrete foundation of the building using the PC plate formwork materials 12 and 13 shown in FIG. 2 (A) and FIG. Explain the construction procedure. First, as shown in FIG. 7, the ground 18 in the area where the concrete foundation of the building is constructed is excavated, and piles 19 and 19 are driven if necessary. Then, the crushed stone or crushed stone 20 is laid on the bottom of the excavated area and compacted with an impactor such as a runner.

  Thereafter, as shown in FIG. 3, a predetermined position at which the base plate 22 is marked on the PC plate frame 10 shown in FIG. 2A in which the longitudinal grooves 15 and 16 in the same direction are formed. The vertical grooves 15 and 16 are erected so that the vertical grooves 15 and 16 face upward. In this case, the worker may hold the posture by gripping it by hand. A PC plate mold material 13 shown in FIG. 2B, which is lifted by a crane or the like from this state, is prepared, and the downward vertical groove 17 is erected in the temporarily placed state. 10 vertical grooves 16 are fitted. In this state, the two PC formwork materials 10 and 13 are L-shaped when viewed in plan, and can stand on their own.

  Next, as shown in FIG. 4, another PC plate formwork 13 is prepared by lifting with a crane, and the downward vertical groove 17 is assembled to the upward vertical groove 15 a of the PC plate formwork 13 previously assembled. Fit. Thereby, the assembly of the three sides is completed.

Finally, as shown in FIG. 5, the PC plate formwork material 12 in which the longitudinal grooves 15 and 16 are formed in the same direction is prepared by lifting the longitudinal grooves 15 and 16 so that the longitudinal grooves 15 and 16 face downward. 15 is fitted into the vertical groove 15 of the PC plate frame member 12 standing upright first, and the other vertical groove 16 is fitted into the upward vertical groove 15a of the PC plate frame member 13 assembled third. Combine.
By the above, as shown in FIG.6 and FIG.7, the construction of the formwork of the concrete foundation part of the pillar part of a building is completed.

After that, it is backfilled with the earth and sand dug up in the space A around the outer periphery of each of the PC frame members 12, 12, 13, and 13 shown in FIG. At this time, the earth pressure of the backfilled earth and sand acts on each PC plate mold frame material, but the earth pressure is transmitted to the adjacent PC plate mold frame material and dispersed, and the opposite PC plate mold frame material Since the earth pressure in the opposite direction acts on each other and cancels each other, these PC plate formwork materials are not collapsed by the earth pressure, do not cause misalignment, and are not lost.

Next, as shown in FIG. 8, the rebar 23 assembled in advance in the space B in the mold is lifted and arranged by a crane or the like, and then the anchor bolt 25 for assembling the steel frame via the positioning plate 24 or the like. 25 is arranged.
Finally, if the concrete 26 is placed in the space B in the formwork, the concrete foundation construction work is completed. Note that the PC plate formwork materials 12, 12, 13, and 13 remain embedded in the soil, and no demolding work is required. Further, these PC plate formwork materials also function as protective layers for the concrete 26, the reinforcing bars 23, and the like.

After the concrete foundation is constructed, a concrete base of a column type 27 is provided, and anchor bolts 25 and 25 are inserted into a base plate 29 of a steel column 28 such as H-shaped steel on the column type 27 and fastened with a nut 30, 28 is erected. Finally, the space C on the upper surface side of the concrete foundation 26 may be backfilled with excavated earth and sand so as to have the same height as the ground surface.

  By the way, in the above description, the concrete foundation of the pillar portion of the building is formed by using two PC plate mold materials 12 having longitudinal grooves in the same direction and two PC plate mold materials 13 having vertical grooves in different directions. Although the case of construction has been described, it is also possible to construct using four PC plate formwork materials 12 having longitudinal grooves in the same direction. In this case, it is only necessary to dispose two pairs of vertically-grooved PC plate formwork members 12 facing each other and to assemble one PC groove form material 12 with the vertically-grooved grooves one by one.

  Moreover, although the said description demonstrated the case where the concrete foundation 26 made a rectangular body, it is applicable also to a pentagonal column body, a hexagonal column body, another polygonal column body, etc. In that case, it is necessary to form the longitudinal grooves obliquely at the same angle as the angle formed between the sides of the polygon. In addition, it is necessary to first use a PC plate formwork having an upward vertical groove in the same direction, and finally, use a PC plate formwork having a downward vertical groove in the same direction. Then, it is sufficient to use a PC plate form material in which upward and downward vertical grooves are formed.

  Moreover, although the above description demonstrated only the case where the concrete foundation 26 was constructed | assembled, when connecting between the concrete foundation 26 and the concrete foundation 26 with an underground beam, the figure (A) of FIG. ) And FIG. 2 (A) and FIG. 2 (B), a recess 31 for connecting to the formwork of the underground beam may be provided at a position indicated by a chain line. In this case, after building the underground beam formwork, the base part for building the pillar part built with the PC plate formwork material and the underground beam part may be simultaneously placed with concrete. .

  By the way, this invention is not limited to embodiment mentioned above, A suitable change is possible. For example, even when a polygonal columnar body is constructed on the ground, it can be constructed using this PC formwork frame material.

DESCRIPTION OF SYMBOLS 10, 11, 12, 13 ... PC formwork material 14 ... Precast concrete plate 15, 15a, 16, 17 ... Vertical groove 18 ... Ground 22 ... Base surface 31 ... Concavity A for underground beam connection ... PC plate Space B on the outer peripheral side of the mold frame material ... Internal space of the PC plate mold material

  In constructing an independent foundation part of a building, etc., the present invention newly develops a precast concrete plate (PC version) discarded frame material, and uses this PC version discarded frame material in a short period of time with other contractors. It is related with the construction method which can construct | assemble a building foundation only by a PC version builder, without performing cooperation.

When constructing the foundation of a pillar of a building, the conventional construction method is to first dig up the ground located in the foundation part and if necessary according to the size of the building, the soil quality, etc. Driving piles. Then, the crushed stones or crushed stones are laid on the bottom ground of the dug groove, and the base surface is formed by compacting with a hammer such as a runner and driving the concrete to a thickness of about 10 cm. .
After that, a frame is formed on this base surface using a wooden formwork made of veneer plywood and piers or a steel formwork, a reinforcing bar is built inside, and concrete is placed in the formwork to form the foundation. Is building. After casting the concrete, the mold was removed from the mold, and then backfilled with earth and sand dug up around the concrete foundation.
The foundation parts of the columns are connected by underground beams.

However, in the construction method generally used in the past, it is necessary to remove the mold by removing the mold after assembling the mold and placing the concrete, and assembling and removing the mold There is a disadvantage that a large space for excavation is required, and the area to be excavated becomes large and the amount of earth and sand discharged is increased. Moreover, it was necessary to temporarily store the excavated earth and sand temporarily in another place, and the space was necessary. Furthermore, the construction of placing concrete after installing the mold and backfilling after demolding has the disadvantage that the number of processes increases and the construction period is prolonged.

Therefore, in recent years, as described in Patent Document 1 or 2, after installing the formwork, the surrounding area is backfilled, and concrete is placed and the formwork is left buried in the soil as it is. Formwork methods have been developed.

The technique of patent document 1 shows the abandonment formwork method which constructs | assembles the cloth foundation erected in T shape from a foundation surface with a precast concrete plate (PC version). Notches are provided on both ends of the PC plate, embedded nuts are planted on the notch end faces, and the adjacent PC plates are connected and fixed together using special L-shaped metal fittings and connecting bolts. I am doing so. After the connection, the PC plate is backfilled with earth and sand dug up the grooves on both sides, and a wooden building is constructed on the upper end surface of the fabric foundation.
In addition, since the PC plate itself constitutes the fabric foundation, the PC plate itself was used as a formwork material and concrete was not placed.

The technique of patent document 2 is a technique in the case of constructing an underground beam using a keystone plate (steel formwork of a hot dip galvanized copper plate). First, the excavation groove having the same width as that of the underground beam is dug up. And the crushed stones or crushed stones are laid side by side on the bottom side of the excavation groove, and the crushed stone having a thickness of about 5 to 10 cm is placed. Next, support bars are erected in the excavation groove almost vertically at intervals along both sides, and steel plates such as keystone plates as a formwork material are supported on these support bars. A pair of opposing metal molds is provided. After that, slab reinforcing bars are placed on the upper surface side of the area surrounded by underground beams, and underground beam reinforcing bars are placed inside the underground beams, and these slab reinforcing bars and underground beam reinforcing bars The concrete is assembled integrally, and concrete is cast in a series from the slab to the steel plate formwork.

Conventionally, the technique shown in FIG. 9 is known as a method for constructing a pillar foundation using a keystone plate. In this prior art, an L-shaped angle member 2 or a runner member is fixed at a predetermined position on the discarded surface 1 of the bottom surface of the excavated groove, and a continuous rectangular wave-shaped keystone plate 3 is erected on the outer peripheral surface side. The L-shaped angle member 4 is fixed to the upper end surface side by welding. The L-shaped joint 5 is welded in the vertical direction at the corner where the adjacent keystone plates 3 come into contact with each other. Further, in order to increase the overall rigidity, a reinforcing connecting member (crossed) 6 is welded to the upper end surface of the corner portion. This is because if the rigidity is not increased, the surrounding earth pressure during backfilling cannot be withstood.
In addition, the opening 7 provided in the upper center part of a pair of opposing keystone plates 3 and 3 is for connecting with an underground beam.

JP-A-8-296239 Japanese Patent No. 2629482

In the technique shown in Patent Document 1, since the PC plate-discarding formwork is left as it is buried in the soil, it is not necessary to remove the mold, and the construction period can be shortened. There is a problem that it cannot be used as it is as a construction.
The foundation of the building pillar depends on the size of the building, etc., but the length of one side of the rectangular body is usually 2m to 3m and the height is 1.2m to 1.5m. After the formation, when the surrounding excavation groove is backfilled with the earth and sand that has been dug up, a considerably large earth pressure acts on the PC plate formwork material. For this reason, when the PC plate formwork members are connected using dedicated L-shaped metal fittings and bolts, the stress of earth pressure acting on the entire PC plate formwork material concentrates on the connecting portion, and the L-type metal fittings and bolt portions The PC plate formwork material was damaged, and the PC plate formwork material fell to the inside, which was the space area of the foundation part where concrete had to be placed, and the formwork could not be assembled.

  Moreover, in the construction method of this patent document 1, a special L-shaped metal fitting must be manufactured and prepared, a notch having a specific shape is formed in the PC plate mold frame material, and bolts are fastened to the notch portion. It is necessary to plant embedded nuts, and extra steps such as mounting brackets and fastening bolts are required when assembling PC formwork materials, which increases the number of processing and assembly processes as a whole, and increases costs. It was also the cause of.

Moreover, in the technique shown in Patent Document 2 etc., a reinforcing bar is inserted into the soil at predetermined intervals in portions along both sides of the excavation groove, and a keystone plate is arranged by leaning on the reinforcing bar. It is a discarded formwork for pouring concrete.
However, such a technique is used as a formwork material for a large-capacity columnar foundation with a side of a rectangular body of 2 m to 3 m and a height of 1.2 m to 1.5 m even if it is normal. This was not possible because of the large earth pressure.

Therefore, when using a keystone plate, it is necessary to weld the upper and lower end surfaces of the keystone plate 3 with L-shaped angle members or runner members 2 having a U-shaped cross section, as shown in the prior art of FIG. In addition, the L-joint 5 is welded to the corner where the keystone plates 3 come into contact with each other, and the connecting material (diagonal) 6 is welded to the corner on the upper end side to increase the overall rigidity. I had to.
Therefore, in the prior art shown in FIG. 9, a welding worker is required in addition to the construction worker, and the cooperative work between the two is indispensable, and the construction worker cannot assemble the formwork alone. There was a problem and an accident based on inadequate cooperation. In addition to the mold material of the keystone plate 3, additional parts such as L-shaped angle or runner members 2, 4, L-shaped joint 5, connecting material (diagonal crossing) 6 are necessary. There is also a problem that management requires labor and cost, and the work becomes complicated. Furthermore, it is a metal formwork material and has a problem that it corrodes due to aging.

Therefore, the present invention is an improvement and removal in view of the above-mentioned conventional problems, in which a vertical groove is provided in a precast concrete plate (PC plate) and the vertical grooves of adjacent precast concrete plates are fitted to each other. By doing so, we intend to provide a PC plate formwork material for column foundation construction that can sufficiently withstand earth pressure, and a construction method using this.

The means of claim 1 adopted by the present invention in order to solve the above-mentioned problem is to provide an upward vertical groove on one end side of a rectangular precast concrete plate and a downward vertical groove on the other end side. Each of the vertical grooves in the vertical direction can be fitted with the vertical grooves in the vertical direction provided in the adjacent precast concrete plate.

The means of claim 2 adopted by the present invention in order to solve the above problem is a resection in which a part from the upper end surface or the lower end surface to the middle of the longitudinal groove is cut in the region from the longitudinal groove to the end. It is a PC formwork frame material of the said Claim 1 which provided the part .

The means of claim 3 adopted by the present invention in order to solve the above problem is that a concave portion for connection with the formwork for underground beam is formed in the middle portion of the upper end surface of the precast concrete plate toward the middle of the lower end side. The PC formwork material according to claim 1 or 2, which is used.

Means according to claim 4 in which the present invention is adopted to solve the above problems, the base surface is placed on its bottom surface with discard configuration like dig the position of the ground to build the foundation of the building, the same at both ends first A precast concrete plate with an upward vertical groove in the direction is installed on the base surface, and a precast concrete plate with a second upward groove and a downward vertical groove is prepared as the first precast. Prepare a precast concrete plate in which the downward vertical groove of the second precast concrete plate is fitted into the upward vertical groove of the concrete plate, and the third upward upward groove and downward vertical groove are formed. Fit the downward vertical groove of the third precast concrete plate into the upward vertical groove of the second precast concrete plate, and the downward vertical groove of the fourth direction in the same direction. There was prepared a precast concrete panel, which is formed to form a third and the first precast concrete panel of each fitted a downward flutes fourth precast concrete panel upward flutes mold, the A foundation construction method using a PC formwork material characterized in that it is backfilled with earth and sand dug up around the formwork and concrete is placed in the formwork to construct the foundation of the building It is.

The means of claim 5 adopted by the present invention in order to solve the above problem is to dig up the ground at the position where the foundation of the building is constructed and install a base surface by discarding or the like on the bottom surface thereof, on the base surface, When building concrete foundations such as pentagonal columns, hexagonal columns, and other polygonal columns, rectangular precast concrete slabs with upward vertical grooves in the same direction on both ends and upwards on both ends Prepare a rectangular precast concrete plate with a vertical groove and a downward vertical groove, and a rectangular precast concrete plate with a downward vertical groove in the same direction on both ends. Precast concrete that has each vertical groove of the plate formed obliquely at the same angle as the angle formed by each side of the polygon, and has an upward vertical groove in the same direction on both ends at the beginning of erection The plate is erected on the base surface, and from the second to the last front, the upward and downward vertical grooves are formed. A formwork is formed by fitting a precast concrete plate having a downward groove in the same direction in the vertical groove and fitting an upward vertical groove in the precast concrete plate from the beginning to the end. It is a foundation construction method using a PC plate formwork characterized in that it is backfilled with earth and sand that has been dug up, and concrete is placed in the formwork to construct the foundation of the building. .

According to the first aspect of the present invention, an upward vertical groove is provided on one end side of the rectangular precast concrete plate, and a downward vertical groove is provided on the other end side. When constructing the foundation of a building, it is only necessary to fit the upward vertical groove and the downward vertical groove provided in the adjacent precast concrete slab.

In the case of the PC formwork material of this claim 1, since welding work is unnecessary, it is possible to build the formwork only by the PC version builder, resulting from poor cooperation between different traders. It is possible to prevent accidents. It is also possible to reduce the burden on construction workers by simplifying the assembly work itself.

In the invention of claim 2 , in the region from the vertical groove to the end, a cut-out portion is provided by cutting off a portion from the upper end surface or the lower end surface to the middle of the vertical groove. This excised part does not function as an opposing means such as earth pressure, and is an essentially unnecessary part. By cutting, it is possible to reduce the material cost.

In the invention of claim 3 , the underground beam is provided in the foundation part of the building, the reinforcement of the foundation part and the reinforcement of the underground beam are assembled together, and concrete is also cast. It is possible to perform the foundation part and the underground beam at the same time.

The invention of claim 4 is a construction method until the foundation part formwork is actually built using the PC plate formwork material of claim 1 to 3 and concrete is placed. On the base surface of the building foundation, install a precast concrete plate with upward vertical grooves in the same direction on both ends , then another precast with upward vertical grooves and downward vertical grooves A concrete plate is prepared, and the downward vertical groove is fitted into the upward vertical groove of the first precast concrete plate, and the adjacent precast concrete plates are combined and combined. A precast concrete plate having a third upward groove and a downward vertical groove is prepared, and the downward vertical groove is fitted into the upward vertical groove of the second precast concrete plate. Finally, prepare a precast concrete slab in which downward flutes in the same direction are formed on both ends, and make the downward flutes on both ends into the upward flutes of the first and third precast concrete slabs, respectively. The formwork is built by fitting .

And backfill with earth and sand dug up around the formwork. The earth pressure at this time is transmitted to the adjacent precast concrete plate and dispersed, and the earth pressure in the opposite direction acts from the opposing precast concrete plate and cancels each other. There is no such thing as collapse or loss.
Moreover, the pressure of the concrete poured into the foundation formwork built with the precast concrete plate acts on each precast concrete plate, but it is enough because the outer periphery of each precast concrete plate is filled with earth and sand that has been backfilled. It is backed up and there is no problem.

In addition, since the precast concrete plate can be built and the earth and sand dug up can be backfilled almost simultaneously, the time for temporarily placing the earth and sand dug up can be shortened. In addition, since the precast concrete formwork material is embedded in the soil as it is, there is no need for a large space for erection and demolding work, and the amount of earth and sand that is dug up for the foundation construction must be reduced. Can do. It is possible to shorten the work period and reduce the work load.
Further, since no metal material is used, there is no problem of corrosion. Furthermore, since a precast concrete plate is interposed around the concrete foundation portion, it can function as a protective layer for preventing the neutralization of the concrete in the foundation portion and the corrosion of the foundation rebar.

In the invention of claim 5, the concrete foundation is constructed in a pentagonal column, a hexagonal column, other polygonal columns and the like. In that case, it is necessary to form the longitudinal grooves obliquely at the same angle as the angle formed between the sides of the polygon. In addition, it is necessary to use a precast concrete plate with an upward vertical groove in the same direction at the beginning, and finally use a precast concrete plate with a downward vertical groove in the same direction. What is necessary is just to use the precast concrete plate in which the vertical groove was formed. Other functions and effects are the same as those of the fourth aspect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a PC formwork frame according to an embodiment of the present invention, in which FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. (B) is provided with vertical grooves in the vertical direction. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a partially cut-off type PC formwork frame according to an embodiment of the present invention. FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. It is a perspective view at the time of providing this vertical groove. It is a perspective view which concerns on one embodiment of this invention and shows a 1st erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 2nd erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 3rd erection process. It is a perspective view which concerns on one embodiment of this invention, and shows the whole state in which construction of the PC plate formwork was completed. It concerns on one embodiment of this invention, and is the longitudinal cross-section of the basic part of the state which the erection of the PC formwork was completed. The longitudinal section which shows the whole foundation part which shows the state which is related to one embodiment of this invention, and concrete is laid, a pillar type | mold is formed, and the steel frame is built after the completion of construction of a PC formwork FIG. It is a perspective view which shows the whole steel formwork for demonstrating the construction method of the foundation part using the conventional keystone plate.

  The configuration of the present invention will be described below based on an embodiment shown in the drawings. 1 (A) and 1 (B) in FIG. 1 and FIG. 2 (A) and FIG. 2 (B) in FIG. 2 are cases in which the formwork materials 10, 11, 12, and 13 are made of a precast concrete plate (PC plate). It is a perspective view which shows an example. These PC plate form materials 10 to 13 generally have a width of 2.6 m to 4 m and a height of 1 although it depends on the size of the concrete foundation designed according to the size of the building to be constructed. .About 2 m to 1.5 m. This is a case where the length of one side of the concrete foundation corresponds to about 2 m to 3 m and the height is about 1.2 m to 1.5 m. As for the said PC type | mold frame materials 10-13, the reinforcing bar is arranged inside, and thickness is about 50 mm-150 mm. In the experiment, 60 mm was sufficient when constructing the foundation of a rectangular column having a side length of 2 m and a height of 1.2 m.

  A PC formwork material 10 shown in FIG. 1A is provided with longitudinal grooves 15 and 16 in the same direction (upward in the drawing) on both end sides of a rectangular precast concrete plate 14. The depth of the longitudinal grooves 15 and 16 only needs to be slightly larger than ½ of the height dimension. Moreover, the position of the vertical grooves 15 and 16 should just be a position where the dimension between the vertical grooves 15 and 16 corresponds to the length of one side of the concrete foundation to be constructed, and about 200 mm to 300 mm from the left and right side end faces, It is appropriate to enter the inside. The width of the longitudinal grooves 15 and 16 may be a little larger than the thickness of the precast concrete plate.

  The PC formwork material 11 shown in FIG. 1B is a case where an upward vertical groove 15a is formed near the left end surface and a downward vertical groove 17 is formed near the right end surface. Other configurations are the same as those of the PC plate mold material 10 shown in FIG.

  The PC plate formwork material 12 shown in FIG. 2A is a region outside the longitudinal grooves 15 and 16 of the PC plate formwork material 10 shown in FIG. A part of a region in the middle from the upper end surface to the groove bottoms of the vertical grooves 15 and 16 is cut out. The excised part is not a part having a special function as a formwork material, so it was decided not to produce it from the beginning to contribute to reducing the material cost. Further, by cutting, there is also an advantage that the vertical grooves can be easily fitted together when assembling the PC plate form material described later.

  The PC plate formwork 13 shown in FIG. 2B is the outer side of the longitudinal groove 15a of the PC plate formwork 11 shown in FIG. A part of a region in the middle from the vertical groove 15a to the groove bottom of the vertical groove 15a, and a region outside the vertical groove 17 and from the lower end surface of the precast concrete plate 14 to the groove bottom of the vertical groove 17 respectively. A part of the middle region is excised. About the effect of a cutting part, it is the same as that of the case of the PC plate mold frame material 12 shown to the figure (A) of the said FIG.

  Next, referring to FIG. 3 to FIG. 7, the formwork in the case of constructing the concrete foundation of the building using the PC plate formwork materials 12 and 13 shown in FIG. 2 (A) and FIG. Explain the construction procedure. First, as shown in FIG. 7, the ground 18 in the area where the concrete foundation of the building is constructed is excavated, and piles 19 and 19 are driven if necessary. Then, the crushed stone or crushed stone 20 is laid on the bottom of the excavated area and compacted with an impactor such as a runner.

  Thereafter, as shown in FIG. 3, a predetermined position at which the base plate 22 is marked on the PC plate frame 10 shown in FIG. 2A in which the longitudinal grooves 15 and 16 in the same direction are formed. The vertical grooves 15 and 16 are erected so that the vertical grooves 15 and 16 face upward. In this case, the worker may hold the posture by gripping it by hand. A PC plate mold material 13 shown in FIG. 2B, which is lifted by a crane or the like from this state, is prepared, and the downward vertical groove 17 is erected in the temporarily placed state. 10 vertical grooves 16 are fitted. In this state, the two PC formwork materials 10 and 13 are L-shaped when viewed in plan, and can stand on their own.

  Next, as shown in FIG. 4, another PC plate formwork 13 is prepared by lifting with a crane, and the downward vertical groove 17 is assembled to the upward vertical groove 15 a of the PC plate formwork 13 previously assembled. Fit. Thereby, the assembly of the three sides is completed.

Finally, as shown in FIG. 5, the PC plate formwork material 12 in which the longitudinal grooves 15 and 16 are formed in the same direction is prepared by lifting the longitudinal grooves 15 and 16 so that the longitudinal grooves 15 and 16 face downward. 15 is fitted into the vertical groove 15 of the PC plate frame member 12 standing upright first, and the other vertical groove 16 is fitted into the upward vertical groove 15a of the PC plate frame member 13 assembled third. Combine.
By the above, as shown in FIG.6 and FIG.7, the construction of the formwork of the concrete foundation part of the pillar part of a building is completed.

After that, it is backfilled with the earth and sand dug up in the space A around the outer periphery of each of the PC frame members 12, 12, 13, and 13 shown in FIG. At this time, the earth pressure of the backfilled earth and sand acts on each PC plate mold frame material, but the earth pressure is transmitted to the adjacent PC plate mold frame material and dispersed, and the opposite PC plate mold frame material Since the earth pressure in the opposite direction acts on each other and cancels each other, these PC plate formwork materials are not collapsed by the earth pressure, do not cause misalignment, and are not lost.

Next, as shown in FIG. 8, the rebar 23 assembled in advance in the space B in the mold is lifted and arranged by a crane or the like, and then the anchor bolt 25 for assembling the steel frame via the positioning plate 24 or the like. 25 is arranged.
Finally, if the concrete 26 is placed in the space B in the formwork, the concrete foundation construction work is completed. Note that the PC plate formwork materials 12, 12, 13, and 13 remain embedded in the soil, and no demolding work is required. Further, these PC plate formwork materials also function as protective layers for the concrete 26, the reinforcing bars 23, and the like.

After the concrete foundation is constructed, a concrete base of a column type 27 is provided, and anchor bolts 25 and 25 are inserted into a base plate 29 of a steel column 28 such as H-shaped steel on the column type 27 and fastened with a nut 30, 28 is erected. Finally, the space C on the upper surface side of the concrete foundation 26 may be backfilled with excavated earth and sand so as to have the same height as the ground surface.

  By the way, in the above description, the concrete foundation of the pillar portion of the building is formed by using two PC plate mold materials 12 having longitudinal grooves in the same direction and two PC plate mold materials 13 having vertical grooves in different directions. Although the case of construction has been described, it is also possible to construct using four PC plate formwork materials 12 having longitudinal grooves in the same direction. In this case, it is only necessary to dispose two pairs of vertically-grooved PC plate formwork members 12 facing each other and to assemble one PC groove form material 12 with the vertically-grooved grooves one by one.

  Moreover, although the said description demonstrated the case where the concrete foundation 26 made a rectangular body, it is applicable also to a pentagonal column body, a hexagonal column body, another polygonal column body, etc. In that case, it is necessary to form the longitudinal grooves obliquely at the same angle as the angle formed between the sides of the polygon. In addition, it is necessary to first use a PC plate formwork having an upward vertical groove in the same direction, and finally, use a PC plate formwork having a downward vertical groove in the same direction. Then, it is sufficient to use a PC plate form material in which upward and downward vertical grooves are formed.

  Moreover, although the above description demonstrated only the case where the concrete foundation 26 was constructed | assembled, when connecting between the concrete foundation 26 and the concrete foundation 26 with an underground beam, the figure (A) of FIG. ) And FIG. 2 (A) and FIG. 2 (B), a recess 31 for connecting to the formwork of the underground beam may be provided at a position indicated by a chain line. In this case, after building the underground beam formwork, the base part for building the pillar part built with the PC plate formwork material and the underground beam part may be simultaneously placed with concrete. .

  By the way, this invention is not limited to embodiment mentioned above, A suitable change is possible. For example, even when a polygonal columnar body is constructed on the ground, it can be constructed using this PC formwork frame material.

DESCRIPTION OF SYMBOLS 10, 11, 12, 13 ... PC formwork material 14 ... Precast concrete plate 15, 15a, 16, 17 ... Vertical groove 18 ... Ground 22 ... Base surface 31 ... Concavity A for underground beam connection ... PC plate Space B on the outer peripheral side of the mold frame material ... Internal space of the PC plate mold material

  In constructing an independent foundation part of a building, etc., the present invention newly develops a precast concrete plate (PC version) discarded frame material, and uses this PC version discarded frame material in a short period of time with other contractors. It is related with the construction method which can construct | assemble a building foundation only by a PC version builder, without performing cooperation.

When constructing the foundation of a pillar of a building, the conventional construction method is to first dig up the ground located in the foundation part and if necessary according to the size of the building, the soil quality, etc. Driving piles. Then, the crushed stones or crushed stones are laid on the bottom ground of the dug groove, and the base surface is formed by compacting with a hammer such as a runner and driving the concrete to a thickness of about 10 cm. .
After that, a frame is formed on this base surface using a wooden formwork made of veneer plywood and piers or a steel formwork, a reinforcing bar is built inside, and concrete is placed in the formwork to form the foundation. Is building. After casting the concrete, the mold was removed from the mold, and then backfilled with earth and sand dug up around the concrete foundation.
The foundation parts of the columns are connected by underground beams.

However, in the construction method generally used in the past, it is necessary to remove the mold by removing the mold after assembling the mold and placing the concrete, and assembling and removing the mold There is a disadvantage that a large space for excavation is required, and the area to be excavated becomes large and the amount of earth and sand discharged is increased. Moreover, it was necessary to temporarily store the excavated earth and sand temporarily in another place, and the space was necessary. Furthermore, the construction of placing concrete after installing the mold and backfilling after demolding has the disadvantage that the number of processes increases and the construction period is prolonged.

Therefore, in recent years, as described in Patent Document 1 or 2, after installing the formwork, the surrounding area is backfilled, and concrete is placed and the formwork is left buried in the soil as it is. Formwork methods have been developed.

The technique of patent document 1 shows the abandonment formwork method which constructs | assembles the cloth foundation erected in T shape from a foundation surface with a precast concrete plate (PC version). Notches are provided on both ends of the PC plate, embedded nuts are planted on the notch end faces, and the adjacent PC plates are connected and fixed together using special L-shaped metal fittings and connecting bolts. I am doing so. After the connection, the PC plate is backfilled with earth and sand dug up the grooves on both sides, and a wooden building is constructed on the upper end surface of the fabric foundation.
In addition, since the PC plate itself constitutes the fabric foundation, the PC plate itself was used as a formwork material and concrete was not placed.

The technique of patent document 2 is a technique in the case of constructing an underground beam using a keystone plate (steel formwork of a hot dip galvanized copper plate). First, the excavation groove having the same width as that of the underground beam is dug up. And the crushed stones or crushed stones are laid side by side on the bottom side of the excavation groove, and the crushed stone having a thickness of about 5 to 10 cm is placed. Next, support bars are erected in the excavation groove almost vertically at intervals along both sides, and steel plates such as keystone plates as a formwork material are supported on these support bars. A pair of opposing metal molds is provided. After that, slab reinforcing bars are placed on the upper surface side of the area surrounded by underground beams, and underground beam reinforcing bars are placed inside the underground beams, and these slab reinforcing bars and underground beam reinforcing bars The concrete is assembled integrally, and concrete is cast in a series from the slab to the steel plate formwork.

Conventionally, the technique shown in FIG. 9 is known as a method for constructing a pillar foundation using a keystone plate. In this prior art, an L-shaped angle member 2 or a runner member is fixed at a predetermined position on the discarded surface 1 of the bottom surface of the excavated groove, and a continuous rectangular wave-shaped keystone plate 3 is erected on the outer peripheral surface side. The L-shaped angle member 4 is fixed to the upper end surface side by welding. The L-shaped joint 5 is welded in the vertical direction at the corner where the adjacent keystone plates 3 come into contact with each other. Further, in order to increase the overall rigidity, a reinforcing connecting member (crossed) 6 is welded to the upper end surface of the corner portion. This is because if the rigidity is not increased, the surrounding earth pressure during backfilling cannot be withstood.
In addition, the opening 7 provided in the upper center part of a pair of opposing keystone plates 3 and 3 is for connecting with an underground beam.

JP-A-8-296239 Japanese Patent No. 2629482

In the technique shown in Patent Document 1, since the PC plate-discarding formwork is left as it is buried in the soil, it is not necessary to remove the mold, and the construction period can be shortened. There is a problem that it cannot be used as it is as a construction.
The foundation of the building pillar depends on the size of the building, etc., but the length of one side of the rectangular body is usually 2m to 3m and the height is 1.2m to 1.5m. After the formation, when the surrounding excavation groove is backfilled with the earth and sand that has been dug up, a considerably large earth pressure acts on the PC plate formwork material. For this reason, when the PC plate formwork members are connected using dedicated L-shaped metal fittings and bolts, the stress of earth pressure acting on the entire PC plate formwork material concentrates on the connecting portion, and the L-type metal fittings and bolt portions The PC plate formwork material was damaged, and the PC plate formwork material fell to the inside, which was the space area of the foundation part where concrete had to be placed, and the formwork could not be assembled.

  Moreover, in the construction method of this patent document 1, a special L-shaped metal fitting must be manufactured and prepared, a notch having a specific shape is formed in the PC plate mold frame material, and bolts are fastened to the notch portion. It is necessary to plant embedded nuts, and extra steps such as mounting brackets and fastening bolts are required when assembling PC formwork materials, which increases the number of processing and assembly processes as a whole, and increases costs. It was also the cause of.

Moreover, in the technique shown in Patent Document 2 etc., a reinforcing bar is inserted into the soil at predetermined intervals in portions along both sides of the excavation groove, and a keystone plate is arranged by leaning on the reinforcing bar. It is a discarded formwork for pouring concrete.
However, such a technique is used as a formwork material for a large-capacity columnar foundation with a side of a rectangular body of 2 m to 3 m and a height of 1.2 m to 1.5 m even if it is normal. This was not possible because of the large earth pressure.

Therefore, when using a keystone plate, it is necessary to weld the upper and lower end surfaces of the keystone plate 3 with L-shaped angle members or runner members 2 having a U-shaped cross section, as shown in the prior art of FIG. In addition, the L-joint 5 is welded to the corner where the keystone plates 3 come into contact with each other, and the connecting material (diagonal) 6 is welded to the corner on the upper end side to increase the overall rigidity. I had to.
Therefore, in the prior art shown in FIG. 9, a welding worker is required in addition to the construction worker, and the cooperative work between the two is indispensable, and the construction worker cannot assemble the formwork alone. There was a problem and an accident based on inadequate cooperation. In addition to the mold material of the keystone plate 3, additional parts such as L-shaped angle or runner members 2, 4, L-shaped joint 5, connecting material (diagonal crossing) 6 are necessary. There is also a problem that management requires labor and cost, and the work becomes complicated. Furthermore, it is a metal formwork material and has a problem that it corrodes due to aging.

Therefore, the present invention is an improvement and removal in view of the above-mentioned conventional problems, in which a vertical groove is provided in a precast concrete plate (PC plate) and the vertical grooves of adjacent precast concrete plates are fitted to each other. By doing so, we intend to provide a PC plate formwork material for column foundation construction that can sufficiently withstand earth pressure, and a construction method using this.

The means of claim 1 adopted by the present invention in order to solve the above-mentioned problem is to provide an upward vertical groove on one end side of a rectangular precast concrete plate and a downward vertical groove on the other end side. Each of the vertical grooves in the vertical direction can be fitted with the vertical grooves in the vertical direction provided in the adjacent precast concrete plate.

The means of claim 2 adopted by the present invention in order to solve the above problems is a portion in which the rising height dimension from the groove bottom is shorter than the dimension of the entire longitudinal groove in the region between the longitudinal groove and the end. The PC plate mold material according to claim 1, wherein:

The means of claim 3 adopted by the present invention in order to solve the above problem is that a concave portion for connection with the formwork for underground beam is formed in the middle portion of the upper end surface of the precast concrete plate toward the middle of the lower end side. The PC formwork material according to claim 1 or 2, which is used.

Means according to claim 4 in which the present invention is adopted to solve the above problems, the base surface is placed on its bottom surface with discard configuration like dig the position of the ground to build the foundation of the building, the same at both ends first A precast concrete plate with an upward vertical groove in the direction is installed on the base surface, and a precast concrete plate with a second upward groove and a downward vertical groove is prepared as the first precast. Prepare a precast concrete plate in which the downward vertical groove of the second precast concrete plate is fitted into the upward vertical groove of the concrete plate, and the third upward upward groove and downward vertical groove are formed. Fit the downward vertical groove of the third precast concrete plate into the upward vertical groove of the second precast concrete plate, and the downward vertical groove of the fourth direction in the same direction. There was prepared a precast concrete panel, which is formed to form a third and the first precast concrete panel of each fitted a downward flutes fourth precast concrete panel upward flutes mold, the A foundation construction method using a PC formwork material characterized in that it is backfilled with earth and sand dug up around the formwork and concrete is placed in the formwork to construct the foundation of the building It is.

The means of claim 5 adopted by the present invention in order to solve the above problem is to dig up the ground at the position where the foundation of the building is constructed and install a base surface by discarding or the like on the bottom surface thereof, on the base surface, When building concrete foundations such as pentagonal columns, hexagonal columns, and other polygonal columns, rectangular precast concrete slabs with upward vertical grooves in the same direction on both ends and upwards on both ends Prepare a rectangular precast concrete plate with a vertical groove and a downward vertical groove, and a rectangular precast concrete plate with a downward vertical groove in the same direction on both ends. Precast concrete that has each vertical groove of the plate formed obliquely at the same angle as the angle formed by each side of the polygon, and has an upward vertical groove in the same direction on both ends at the beginning of erection The plate is erected on the base surface, and from the second to the last front, the upward and downward vertical grooves are formed. A formwork is formed by fitting a precast concrete plate having a downward groove in the same direction in the vertical groove and fitting an upward vertical groove in the precast concrete plate from the beginning to the end. It is a foundation construction method using a PC plate formwork characterized in that it is backfilled with earth and sand that has been dug up, and concrete is placed in the formwork to construct the foundation of the building. .

According to the first aspect of the present invention, an upward vertical groove is provided on one end side of the rectangular precast concrete plate, and a downward vertical groove is provided on the other end side. When constructing the foundation of a building, it is only necessary to fit the upward vertical groove and the downward vertical groove provided in the adjacent precast concrete slab.

In the case of the PC formwork material of this claim 1, since welding work is unnecessary, it is possible to build the formwork only by the PC version builder, resulting from poor cooperation between different traders. It is possible to prevent accidents. It is also possible to reduce the burden on construction workers by simplifying the assembly work itself.

In the invention of claim 2 , in the region from the vertical groove to the end, a portion where the height of the rising from the groove bottom is shorter than the entire vertical groove is provided . The part where the dimension is shortened does not function as an opposing means such as earth pressure, and is an essentially unnecessary part. By shortening, it is possible to reduce the material cost.

In the invention of claim 3 , the underground beam is provided in the foundation part of the building, the reinforcement of the foundation part and the reinforcement of the underground beam are assembled together, and concrete is also cast. It is possible to perform the foundation part and the underground beam at the same time.

The invention of claim 4 is a construction method until the foundation part formwork is actually built using the PC plate formwork material of claim 1 to 3 and concrete is placed. On the base surface of the building foundation, install a precast concrete plate with upward vertical grooves in the same direction on both ends , then another precast with upward vertical grooves and downward vertical grooves A concrete plate is prepared, and the downward vertical groove is fitted into the upward vertical groove of the first precast concrete plate, and the adjacent precast concrete plates are combined and combined. A precast concrete plate having a third upward groove and a downward vertical groove is prepared, and the downward vertical groove is fitted into the upward vertical groove of the second precast concrete plate. Finally, prepare a precast concrete slab in which downward flutes in the same direction are formed on both ends, and make the downward flutes on both ends into the upward flutes of the first and third precast concrete slabs, respectively. The formwork is built by fitting .

And backfill with earth and sand dug up around the formwork. The earth pressure at this time is transmitted to the adjacent precast concrete plate and dispersed, and the earth pressure in the opposite direction acts from the opposing precast concrete plate and cancels each other. There is no such thing as collapse or loss.
Moreover, the pressure of the concrete poured into the foundation formwork built with the precast concrete plate acts on each precast concrete plate, but it is enough because the outer periphery of each precast concrete plate is filled with earth and sand that has been backfilled. It is backed up and there is no problem.

In addition, since the precast concrete plate can be built and the earth and sand dug up can be backfilled almost simultaneously, the time for temporarily placing the earth and sand dug up can be shortened. In addition, since the precast concrete formwork material is embedded in the soil as it is, there is no need for a large space for erection and demolding work, and the amount of earth and sand that is dug up for the foundation construction must be reduced. Can do. It is possible to shorten the work period and reduce the work load.
Further, since no metal material is used, there is no problem of corrosion. Furthermore, since a precast concrete plate is interposed around the concrete foundation portion, it can function as a protective layer for preventing the neutralization of the concrete in the foundation portion and the corrosion of the foundation rebar.

In the invention of claim 5, the concrete foundation is constructed in a pentagonal column, a hexagonal column, other polygonal columns and the like. In that case, it is necessary to form the longitudinal grooves obliquely at the same angle as the angle formed between the sides of the polygon. In addition, it is necessary to use a precast concrete plate with an upward vertical groove in the same direction at the beginning, and finally use a precast concrete plate with a downward vertical groove in the same direction. What is necessary is just to use the precast concrete plate in which the vertical groove was formed. Other functions and effects are the same as those of the fourth aspect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a PC formwork frame according to an embodiment of the present invention, in which FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. (B) is provided with vertical grooves in the vertical direction. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a partially cut-off type PC formwork frame according to an embodiment of the present invention. FIG. (A) is a perspective view when vertical grooves are provided in the same direction, and FIG. It is a perspective view at the time of providing this vertical groove. It is a perspective view which concerns on one embodiment of this invention and shows a 1st erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 2nd erection process. It is a perspective view which concerns on one embodiment of this invention and shows a 3rd erection process. It is a perspective view which concerns on one embodiment of this invention, and shows the whole state in which construction of the PC plate formwork was completed. It concerns on one embodiment of this invention, and is the longitudinal cross-section of the basic part of the state which the erection of the PC formwork was completed. The longitudinal section which shows the whole foundation part which shows the state which is related to one embodiment of this invention, and concrete is laid, a pillar type | mold is formed, and the steel frame is built after the completion of construction of a PC formwork FIG. It is a perspective view which shows the whole steel formwork for demonstrating the construction method of the foundation part using the conventional keystone plate.

  The configuration of the present invention will be described below based on an embodiment shown in the drawings. 1 (A) and 1 (B) in FIG. 1 and FIG. 2 (A) and FIG. 2 (B) in FIG. 2 are cases in which the formwork materials 10, 11, 12, and 13 are made of a precast concrete plate (PC plate). It is a perspective view which shows an example. These PC plate form materials 10 to 13 generally have a width of 2.6 m to 4 m and a height of 1 although it depends on the size of the concrete foundation designed according to the size of the building to be constructed. .About 2 m to 1.5 m. This is a case where the length of one side of the concrete foundation corresponds to about 2 m to 3 m and the height is about 1.2 m to 1.5 m. As for the said PC type | mold frame materials 10-13, the reinforcing bar is arranged inside, and thickness is about 50 mm-150 mm. In the experiment, 60 mm was sufficient when constructing the foundation of a rectangular column having a side length of 2 m and a height of 1.2 m.

  A PC formwork material 10 shown in FIG. 1A is provided with longitudinal grooves 15 and 16 in the same direction (upward in the drawing) on both end sides of a rectangular precast concrete plate 14. The depth of the longitudinal grooves 15 and 16 only needs to be slightly larger than ½ of the height dimension. Moreover, the position of the vertical grooves 15 and 16 should just be a position where the dimension between the vertical grooves 15 and 16 corresponds to the length of one side of the concrete foundation to be constructed, and about 200 mm to 300 mm from the left and right side end faces, It is appropriate to enter the inside. The width of the longitudinal grooves 15 and 16 may be a little larger than the thickness of the precast concrete plate.

  The PC formwork material 11 shown in FIG. 1B is a case where an upward vertical groove 15a is formed near the left end surface and a downward vertical groove 17 is formed near the right end surface. Other configurations are the same as those of the PC plate mold material 10 shown in FIG.

  The PC plate formwork material 12 shown in FIG. 2A is a region outside the longitudinal grooves 15 and 16 of the PC plate formwork material 10 shown in FIG. A part of a region in the middle from the upper end surface to the groove bottoms of the vertical grooves 15 and 16 is cut out. The excised part is not a part having a special function as a formwork material, so it was decided not to produce it from the beginning to contribute to reducing the material cost. Further, by cutting, there is also an advantage that the vertical grooves can be easily fitted together when assembling the PC plate form material described later.

  The PC plate formwork 13 shown in FIG. 2B is the outer side of the longitudinal groove 15a of the PC plate formwork 11 shown in FIG. A part of a region in the middle from the vertical groove 15a to the groove bottom of the vertical groove 15a, and a region outside the vertical groove 17 and from the lower end surface of the precast concrete plate 14 to the groove bottom of the vertical groove 17 respectively. A part of the middle region is excised. About the effect of a cutting part, it is the same as that of the case of the PC plate mold frame material 12 shown to the figure (A) of the said FIG.

  Next, referring to FIG. 3 to FIG. 7, the formwork in the case of constructing the concrete foundation of the building using the PC plate formwork materials 12 and 13 shown in FIG. 2 (A) and FIG. Explain the construction procedure. First, as shown in FIG. 7, the ground 18 in the area where the concrete foundation of the building is constructed is excavated, and piles 19 and 19 are driven if necessary. Then, the crushed stone or crushed stone 20 is laid on the bottom of the excavated area and compacted with an impactor such as a runner.

  Thereafter, as shown in FIG. 3, a predetermined position at which the base plate 22 is marked on the PC plate frame 10 shown in FIG. 2A in which the longitudinal grooves 15 and 16 in the same direction are formed. The vertical grooves 15 and 16 are erected so that the vertical grooves 15 and 16 face upward. In this case, the worker may hold the posture by gripping it by hand. A PC plate mold material 13 shown in FIG. 2B, which is lifted by a crane or the like from this state, is prepared, and the downward vertical groove 17 is erected in the temporarily placed state. 10 vertical grooves 16 are fitted. In this state, the two PC formwork materials 10 and 13 are L-shaped when viewed in plan, and can stand on their own.

  Next, as shown in FIG. 4, another PC plate formwork 13 is prepared by lifting with a crane, and the downward vertical groove 17 is assembled to the upward vertical groove 15 a of the PC plate formwork 13 previously assembled. Fit. Thereby, the assembly of the three sides is completed.

Finally, as shown in FIG. 5, the PC plate formwork material 12 in which the longitudinal grooves 15 and 16 are formed in the same direction is prepared by lifting the longitudinal grooves 15 and 16 so that the longitudinal grooves 15 and 16 face downward. 15 is fitted into the vertical groove 15 of the PC plate frame member 12 standing upright first, and the other vertical groove 16 is fitted into the upward vertical groove 15a of the PC plate frame member 13 assembled third. Combine.
By the above, as shown in FIG.6 and FIG.7, the construction of the formwork of the concrete foundation part of the pillar part of a building is completed.

After that, it is backfilled with the earth and sand dug up in the space A around the outer periphery of each of the PC frame members 12, 12, 13, and 13 shown in FIG. At this time, the earth pressure of the backfilled earth and sand acts on each PC plate mold frame material, but the earth pressure is transmitted to the adjacent PC plate mold frame material and dispersed, and the opposite PC plate mold frame material Since the earth pressure in the opposite direction acts on each other and cancels each other, these PC plate formwork materials are not collapsed by the earth pressure, do not cause misalignment, and are not lost.

Next, as shown in FIG. 8, the rebar 23 assembled in advance in the space B in the mold is lifted and arranged by a crane or the like, and then the anchor bolt 25 for assembling the steel frame via the positioning plate 24 or the like. 25 is arranged.
Finally, if the concrete 26 is placed in the space B in the formwork, the concrete foundation construction work is completed. Note that the PC plate formwork materials 12, 12, 13, and 13 remain embedded in the soil, and no demolding work is required. Further, these PC plate formwork materials also function as protective layers for the concrete 26, the reinforcing bars 23, and the like.

After the concrete foundation is constructed, a concrete base of a column type 27 is provided, and anchor bolts 25 and 25 are inserted into a base plate 29 of a steel column 28 such as H-shaped steel on the column type 27 and fastened with a nut 30, 28 is erected. Finally, the space C on the upper surface side of the concrete foundation 26 may be backfilled with excavated earth and sand so as to have the same height as the ground surface.

  By the way, in the above description, the concrete foundation of the pillar portion of the building is formed by using two PC plate mold materials 12 having longitudinal grooves in the same direction and two PC plate mold materials 13 having vertical grooves in different directions. Although the case of construction has been described, it is also possible to construct using four PC plate formwork materials 12 having longitudinal grooves in the same direction. In this case, it is only necessary to dispose two pairs of vertically-grooved PC plate formwork members 12 facing each other and to assemble one PC groove form material 12 with the vertically-grooved grooves one by one.

  Moreover, although the said description demonstrated the case where the concrete foundation 26 made a rectangular body, it is applicable also to a pentagonal column body, a hexagonal column body, another polygonal column body, etc. In that case, it is necessary to form the longitudinal grooves obliquely at the same angle as the angle formed between the sides of the polygon. In addition, it is necessary to first use a PC plate formwork having an upward vertical groove in the same direction, and finally, use a PC plate formwork having a downward vertical groove in the same direction. Then, it is sufficient to use a PC plate form material in which upward and downward vertical grooves are formed.

  Moreover, although the above description demonstrated only the case where the concrete foundation 26 was constructed | assembled, when connecting between the concrete foundation 26 and the concrete foundation 26 with an underground beam, the figure (A) of FIG. ) And FIG. 2 (A) and FIG. 2 (B), a recess 31 for connecting to the formwork of the underground beam may be provided at a position indicated by a chain line. In this case, after building the underground beam formwork, the base part for building the pillar part built with the PC plate formwork material and the underground beam part may be simultaneously placed with concrete. .

  By the way, this invention is not limited to embodiment mentioned above, A suitable change is possible. For example, even when a polygonal columnar body is constructed on the ground, it can be constructed using this PC formwork frame material.

DESCRIPTION OF SYMBOLS 10, 11, 12, 13 ... PC formwork material 14 ... Precast concrete plate 15, 15a, 16, 17 ... Vertical groove 18 ... Ground 22 ... Base surface 31 ... Concavity A for underground beam connection ... PC plate Space B on the outer peripheral side of the mold frame material ... Internal space of the PC plate mold material

Claims (5)

A longitudinal groove in the same direction is provided on both end sides of a rectangular precast concrete plate, and the longitudinal groove can be fitted with a longitudinal groove provided in an adjacent precast concrete plate. PC formwork material. An upside vertical groove is provided on one end side of a rectangular precast concrete plate, and a downside vertical groove is provided on the other end side. Each vertical groove is provided in the adjacent precast concrete plate. A PC plate form material, which can be fitted into each vertical groove formed in the vertical direction. The PC formwork material according to claim 1 or 2, wherein a portion from the upper end surface or the lower end surface to the middle of the longitudinal groove is cut out in a region between the longitudinal groove and the end portion. The PC plate according to any one of claims 1 to 3, wherein a concave portion for connection with the underground beam formwork is formed in the middle of the upper end surface of the precast concrete plate toward the middle of the lower end side. Formwork material. Dig up the ground at the position to build the foundation of the building, install the base surface by discarding etc. on the bottom surface, install the precast concrete plate with the upward vertical groove formed on the base surface, the precast concrete plate A formwork in which a downward vertical groove of another precast concrete plate is fitted to an upward vertical groove and combined with adjacent precast concrete plates in combination to form an arbitrary polygonal planar shape with multiple precast concrete plates And using a PC formwork material characterized in that the foundation of the building was constructed by placing concrete in the formwork and backfilling it with earth and sand dug up around the formwork. Foundation construction method.

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