JP3655351B2 - Spacer for removing hardened cement in hollow pile - Google Patents

Description

[0001]
[Industrial application fields]
The present invention is a spacer that is inserted in advance in the upper part of a hollow pile that has been excavated by an auger machine or the like and is set in a pile pile that has been filled with concrete for consolidation, and the inside of the set hollow pile The present invention relates to a spacer that is used for removing a predetermined length from the upper end of a hollow pile after the concrete that rises and fills and hardens in the pile.
[0002]
[Prior art]
As a construction method of foundation work for buildings, etc., a method is known in which concrete for solidification is poured into a pile that has been excavated with an auger machine or the like, and then a hollow pile is set in the pile to harden the concrete. It has been. When the hollow pile is set in this construction method, the concrete poured into the pile pile rises and fills the hollow pile, and the surplus concrete overflows from the hollow pile.
[0003]
By the way, since the hollow pile and the underground beam are integrally connected to the upper part of the hollow pile set in the pile, a cage-like reinforcing bar is inserted. It is necessary to remove the filled and hardened concrete and re-create the space for the cage-like reinforcing bars in the upper part of the hollow pile.
[0004]
A spacer for removing the hardened cement in the hollow pile is used to easily remove the hardened concrete by filling the upper part of the hollow pile.
[0005]
As spacers for the above applications, there are known inner and outer double cardboard cylindrical spacers combined via a spacing member, and synthetic resin foam cylindrical spacers with cutouts formed in the vertical direction. (Japanese Patent Laid-Open No. 4-371610). In either case, the cage-shaped support material is encased with the gripping portion exposed upward, and is inserted into the upper part of the hollow pile. By swinging left and right while pulling upward with a heavy machine such as a backhoe, it is possible to separate and remove from the hardened concrete integrated with the hollow pile below.
[0006]
[Problems to be solved by the invention]
By the way, as pointed out in the above-mentioned publication, the cylindrical spacer made of cardboard has a problem that it is difficult to insert the outer cylinder exactly into the hollow pile because it is made of hard cardboard and is cylindrical. In particular, the inner surface of concrete piles often has irregular irregularities, and the accuracy of the inner diameter is not so high. To make it possible to insert regardless of the irregularities on the inner surface or slight differences in inner diameter, the outer cylinder It is necessary to make the diameter slightly smaller, and it is inevitable that a certain amount of gap is generated between the outer cylinder and the inner surface of the hollow pile. For this reason, concrete entered between the outer cylinder and the inner surface of the hollow pile, and the outer cylinder was firmly attached to the inner surface of the hollow pile, and the outer cylinder was likely to remain in the hollow pile, and the outer cylinder could be removed. Even so, the concrete that has entered between the outer cylinder and the inner surface of the hollow pile remains. In order to perform the construction strictly, the removal is necessary, and there is a problem that the removal work takes a lot of time and effort.
[0007]
On the other hand, a spacer made of a synthetic resin foam and having a notch in the vertical direction has a certain degree of flexibility in material and can be reduced in diameter by narrowing the notch. Therefore, there is an advantage that it can be fitted to the inner surface of the hollow pile regardless of the unevenness of the inner surface or some difference in inner diameter.
[0008]
However, although it has the above-mentioned advantages, even if it can be reduced in diameter, it cannot be expanded. Therefore, it cannot cope with the case where the inner diameter of the hollow pile is larger than expected. Spacers have to be prepared, and there is a problem that flexibility to hollow piles of different diameters is lacking. Moreover, since it has a notch part in the vertical direction, as it is, the concrete that has risen in the spacer is integrated with the inner surface of the hollow pile via the notch part, and this prevents the hardened concrete in the spacer from being separated and removed. Therefore, it is necessary to wrap and insert a synthetic resin film or the like around the outer periphery or the inner periphery, or shift the position of the notch portion and insert it in combination with the inner and outer doubles, resulting in troublesome work on site.
[0009]
The present invention has been made in view of the above-described conventional problems, and a spacer that can be fitted to the inner surface of the hollow pile regardless of the unevenness or the diameter of the inner surface of the hollow pile, and that can be easily inserted in the field is provided. The purpose is to provide.
[0010]
[Means for Solving the Problems]
For this reason, in the present invention, as shown in FIGS. 1 to 3, a plate-like body made of a polyolefin-based synthetic resin foam has a large number of longitudinal grooves 1 formed in parallel on at least both sides of one side. The spacer 3 can be inserted into the hollow pile 2 by being rolled in a state in which the longitudinal groove 1 is formed inward and elastically restored in the parallel direction of the longitudinal grooves 1.
[0011]
Example and operation
An embodiment of the present invention will be described with reference to FIGS.
[0012]
The spacer 3 according to the present invention is a plate-like body made of a polyolefin-based synthetic resin foam, and a plurality of longitudinal grooves 1 are formed in parallel on one side as clearly shown in FIG. As will be described below, the vertical groove 1 is used to facilitate rounding of the spacer 3 into a cylindrical shape along the inner surface of the hollow pile 2 (see FIG. 2). By providing the groove 1 and omitting the longitudinal groove 1 at the center of the spacer 3, the labor and cost of processing can be reduced.
[0013]
As shown in FIG. 2 and FIG. 3, the longitudinal groove 1 can be inserted into the hollow pile 2 by rounding the spacer 3 in the parallel direction of the longitudinal groove 1 with the formation surface of the longitudinal groove 1 inside. Is for. The cross-sectional shape of the longitudinal groove 1 may be a square or a semicircular shape, but is preferably an inverted triangular shape as shown in the figure because it can be easily rounded. The width, interval and depth of the longitudinal groove 1 are preferably adjusted so that they can be easily rounded and an appropriate elastic restoring force is obtained after the rounding.
[0014]
A vertical material holding groove 6 for receiving and holding the vertical material 5 of the support material 4 shown in FIG. 3 is formed in the substantially central portion of the spacer 3 in the same direction as the vertical groove 1. Further, in the upper part and the lower part of the spacer 3, a transverse member holding groove 8 for accommodating and holding the transverse member 7 of the support member 4 is formed in a direction orthogonal to the longitudinal groove 1. The vertical member holding groove 6 and the horizontal member holding groove 8 are not essential, but if they are provided, the support material 4 can be easily contained in a fixed position in the spacer 3, and the support material 4 is used when the spacer 3 is used. Wrapping work becomes easy. In particular, when the cross member holding groove 8 is provided and the cross member 7 of the support member 4 is firmly held therein, the main spacer 3 can be easily removed at the time of separating and removing the hardened cement in the round main spacer 3. In FIG. 1, there is one longitudinal member holding groove 6, but a plurality of longitudinal member holding grooves 6 may be provided.
[0015]
A thin overlapping piece 9 is provided at one edge in the parallel direction of the longitudinal grooves 1 of the spacer 3 so as to overlap the other edge when the spacer 3 is rolled. The overlapping piece 9 is formed integrally with the main body part which is a part other than the overlapping piece 9, or is provided by welding or bonding to the main body part. The overlapping piece 9 is not essential, but if the overlapping piece 9 is provided, both end edges when the spacer 3 is rolled may be overlapped without causing a large step on the outer surface side. This makes it easier to bring the entire outer periphery of the spacer 3 into close contact with the inner surface of the pile 2.
[0016]
In the spacer 3, at least a main body portion other than the overlapping piece 9 needs to be made of a polyolefin-based synthetic resin foam. Polyolefin-based synthetic resin foam is stronger and more flexible and elastic than polystyrene foam, for example, and easily adheres to the inner surface of pile 2 without cracking or chipping. There are difficult advantages. Examples of the polyolefin-based synthetic resin include polyethylene, polypropylene, and a copolymer containing 50% by weight or more of these, preferably polyethylene.
[0017]
The foaming ratio of the polyolefin-based synthetic resin foam constituting the main body is preferably 5 to 100 times, more preferably 20 to 50 times, in order to obtain necessary strength, elasticity and the like. Moreover, it is preferable that the thickness of the main part of this spacer 3 comprised with this polyolefin-type synthetic resin foam is 20-50 mm so that it may be shaken right and left at the time of the division | segmentation removal of the hardened concrete mentioned later.
[0018]
The overlapping piece 9 is also preferably made of a polyolefin-based synthetic resin as described above. In addition, although the overlapping piece 9 is formed thin, it is easy to perform the overlapping operation when the spacer 3 is rolled up if it is a stiff portion. Therefore, the non-foamed polyolefin synthetic resin or A polyolefin-based synthetic resin foam having an expansion ratio of 50 times or less is preferable. In the case of a polyolefin-based synthetic resin foam, it is particularly preferable that the expansion ratio is 5 to 50 times.
[0019]
Next, a method of using the above-described spacer 3 will be described with reference to FIGS.
[0020]
First, when the spacer 3 is rolled as shown in FIG. 2, the support material 4 is wrapped so as to be wrapped as shown in FIG. At this time, the vertical member 5 of the support member 4 is aligned with the vertical member holding groove 6 of the spacer 3, and the horizontal member 7 is aligned with the horizontal member holding groove 8.
[0021]
Here, the support member 4 will be described. The support member 4 is inserted into the upper portion of the pile 2 in a state of being included in the spacer 3, and is usually made of a reinforcing bar material and bent into a substantially oval shape. This is a cage-shaped member comprising a longitudinal member 5 welded to the ends and an annular transverse member 7 attached around the longitudinal member 5. The upper part of the support material 4 is a grip 10 for pulling upward by a heavy machine such as a backhoe. The support material 4 is included in the spacer 3 with the gripping portion 10 exposed upward, and is inserted into the pile 2.
[0022]
A support ring 13 for suspending the support material 4 from the upper end of the hollow pile 2 is provided on the support material 4. Also, a mounting ring 12 is provided at the lower end of the support member 4, and a partition plate 11 is attached to the lower surface side thereof by means such as an adhesive tape or a wire. The mounting ring 12 is not essential, and the partition plate 11 may be attached to the lower end portion of the support member 4 as shown by a dotted line in FIG. Regardless of the presence or absence of the mounting ring 12, the mounting position of the support member 4 may be a position included in the round spacer 3 or a position exposed at the lower end.
[0023]
After the partition plate 11 attached to the mounting ring 12 narrows the inlet of the concrete that rises from below into the main spacer 3 inserted in the hollow pile 2 and the concrete in the hollow pile 2 is hardened. The connecting portion between the hardened concrete in the spacer 3 and the hardened concrete below it is partitioned only by the inflow port so that both can be easily separated.
[0024]
As a specific example of the partition plate 11, as shown in FIG. 4A, for example, a cross 14 or a radial cut 14 is formed at the center of a disc made of a flexible material such as rubber or synthetic resin. A plurality of tongue pieces 15 are formed and the tongue pieces 15 are turned up to allow the inflow of concrete. As shown in FIG. 4B, a narrow slit serving as a concrete inflow port. 16 and the like, as shown in FIG. 4 (c), and the like that leave a gap 17 serving as a concrete inflow port between the rolled spacer 3 and the like.
[0025]
After the support material 4 including the support ring 13, the mounting ring 12 and the partition plate 11 as described above is wrapped with the spacer 3, the support material 4 is inserted into the hollow pile 2. In addition, when the hollow pile 2 is set in the pile pile injected with concrete for root consolidation, the spacer 3 is held by a presser (not shown) so that the concrete is not lifted by the concrete rising in the hollow pile 2. Stop). In order to prevent the spacer 3 from being lifted up, a reinforcing bar material called a barb is fixed across the upper end of the support member 4, and the upper end of the hollow pile 2 into which a steel frame is normally fitted is fixed. This can also be done by pre-welding the knurled bars. In this case, the support ring 13 can be omitted.
[0026]
When the main spacer 3 is rounded and inserted into the hollow pile 2, the central portion is temporarily fixed with, for example, a string, a tape with a tape fastener, or the like from the insertion tip side (lower end side) of the round main spacer 3; If the temporary fixing is removed after a certain amount of insertion, the insertion operation becomes easy.
[0027]
The spacer 3 is simply inserted in a rounded state, and the diameter can be freely adjusted by the rounding method, so that the same spacer 3 can have different diameters as well as irregularities and inner diameter errors on the inner surface of the hollow pile 2. It can be used for various types of hollow piles 2. In addition, the spacer 3 inserted into the hollow pile 2 is elastically restored and expands in diameter, and the spacer 3 has an appropriate elasticity. It easily adheres to the inner surface of the pile 2 and there is almost no gap between the inner surface of the hollow pile 2. Therefore, since the concrete rising in the hollow pile 2 hardly penetrates between the inner surface of the hollow pile 2 and the spacer 3, the spacer 3 is made of a polyolefin-based synthetic resin foam to which the concrete does not easily adhere. It is easy to remove the spacer 3 after curing.
[0028]
By the way, when the main spacer 3 has the overlapping piece 9, if the inner diameter of the hollow pile 2 is small, the rounded edge portion of the main spacer 3 may overlap the overlapping piece 9. In such a case, the length of the spacer 3 may be adjusted by appropriately cutting the spacer 3, but the spacer 3 has a large number of vertical grooves 1, so that the length of the spacer 3 is torn by hand through the vertical grooves 1 at appropriate positions. It can be adjusted and work on site is easy. In particular, if the longitudinal groove 1 has an inverted triangular cross section as shown in FIG. 1, there is an advantage that it is easy to tear by hand.
[0029]
After the spacer 3 is set in the hollow pile 2 as shown in FIG. 3, the hollow pile 2 is built, and as shown in FIG. 5, it is laid in a pile pile injected with concrete for consolidation. Then, after curing, as shown in FIG. 6, the hardened concrete in the spacer 3 is separated from the hardened concrete below and removed.
[0030]
The above-mentioned parting removal is performed by connecting the gripping part 10 of the support material 4 to a heavy machine such as a backhoe, lifting it up and swinging left and right, so that the hardened concrete in the spacer 3 is integrated with the hollow pile 2 below. This can be done by dividing the concrete.
[0031]
Although the above-mentioned division is possible even if the partition plate 11 is not provided, as described above, if this partition plate 11 is provided, the space between the hardened concrete in the spacer 3 and the hardened concrete below the spacer 3 is provided. This is preferable because it is partitioned and easily divided. Further, as described above, since the concrete is difficult to enter between the inner surface of the hollow pile 2 and the concrete does not easily adhere to the spacer 3 as described above, the spacer 3 is easily extracted together with the hardened concrete in the spacer 3, and the residual is removed. Easy to prevent. Further, even if only the hardened concrete is extracted and the spacer 3 remains, it can be easily extracted by pulling it again, and the extraction is not time-consuming.
[0032]
After removing the spacer 3 and the hardened concrete in the spacer 3 in this way, a cage-like reinforcing bar is inserted into the space above the hollow pile 2 opened thereby, and the construction of the underground beam is advanced. Will be.
[0033]
FIG. 7 shows another embodiment of the spacer 3. At least one end edge in the longitudinal groove 1 direction (at least the insertion tip side into the hollow pile 2) on the formation surface side of the longitudinal groove 1 is an outward tapered surface 18. It has become.
[0034]
In this way, the concrete that rises when the hollow pile 2 is set in the shaft that has been filled with concrete for root consolidation flows along the tapered surface 18 as shown by the arrows in FIG. Will be pressed against the inner surface of the hollow pile 2. Therefore, it becomes difficult for concrete to enter between the inner surface of the spacer 3 and the hollow pile 2.
[0035]
【The invention's effect】
The present invention is as described above, and has the following effects.
[0036]
(1) Since it is rolled up on site and inserted into the hollow pile 2 and elastically restored in the hollow pile 2, the inner surface of the hollow pile 2 regardless of the irregularities on the inner surface of the hollow pile 2 or the inner diameter error of the hollow pile 2 Can be adhered to.
[0037]
(2) For the same reason as described above, the same spacer 3 can be used for different types of hollow piles 2 having different diameters, and the versatility is high.
[0038]
(3) Because it is in close contact with the inner surface of the hollow pile 2 by elastic restoring force, it is made of a polyolefin-based synthetic resin foam that is difficult for concrete to enter between the spacer 3 and the inner surface of the hollow pile 2 and to which the concrete does not easily adhere. Removal is easy, and post-processing such as fishing can be omitted.
[0039]
(4) Since it is composed of a single product and does not need to be used in combination with a plurality of parts, workability on site is good.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a spacer according to the present invention.
FIG. 2 is a perspective view showing a state in which the spacer of FIG. 1 is rounded.
3 is a cross-sectional view showing a state in which a support material is included in the spacer of FIG.
FIG. 4 is a view showing a partition plate.
FIG. 5 is a cross-sectional view of a state where the hollow pile with the spacers of FIG. 1 is set on a pile pile poured with solidified concrete.
FIG. 6 is a cross-sectional view showing a state in which the hardened concrete in the spacer is being cut out from the hardened concrete below the spacer.
FIG. 7 is a cross-sectional view showing another embodiment of the spacer according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Longitudinal groove 2 Hollow pile 3 Spacer 4 Support material 5 Longitudinal material 6 Longitudinal material holding groove 7 Lateral material 8 Lateral material holding groove 9 Overlapping part 10 Holding part 11 Partition plate 12 Mounting ring 13 Support ring 14 Cut 15 Tongue piece 16 Slit 17 Clearance 18 Tapered surface

Claims (5)

A plate-shaped body made of a polyolefin-based synthetic resin foam. A large number of vertical grooves are formed in parallel on at least both sides of one side, and the vertical groove can be used as an inner surface to return elastically in the parallel direction of the vertical grooves. A spacer for removing hardened cement in a hollow pile, which is rolled in a state and can be inserted into the hollow pile. The hollow pile internal hardened cement removing spacer according to claim 1, wherein a thin overlapping piece is provided on one end edge of the longitudinal grooves in the parallel direction so as to overlap the other end edge when rounded. The hollow pile internal hardened cement removing spacer according to claim 1 or 2, wherein the longitudinal groove has an inverted triangular cross section. 4. A hollow pile internal hardening according to claim 1, wherein a transverse member holding groove is formed on a surface of the longitudinal groove in a direction orthogonal to the longitudinal groove and meshes with the transverse member of the support material to be included. Cement removal spacer. The hollow pile inner hardened cement removing spacer according to any one of claims 1 to 4, wherein at least one end edge in the longitudinal groove direction side of the longitudinal groove forming surface side is an outwardly tapered surface.

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