JPH04366229A - Temporary corresponding standard used for method of reverse driving construction - Google Patents

Abstract

PURPOSE:To reduce the cost of a method of reverse driving construction by previously welding and connecting temporary standards made of H steel, etc., in series with the pile head of a precast pile and unifying the temporary standards and building the pile head into a pile hole. CONSTITUTION:A temporary corresponding standard 1, in which H steel 5 is welded and connected to the head of a precast PC pile 3, is built at the position of a mainly built post, and soil and sand are excavated and removed for constructing a basement. A steel-plate pedestal plate 11 fixing an anchor bolt is welded to the cut surface of the H steel 5, and the section of the H steel 5 is cut and a mainly built steel post 9 is connected and disposed in upright. A support material 13 for the standard is stretched horizontally between the H steel 5, and the mainly built steel post 9 is fixed onto the pedestal plate 11. Soil is excavated and removed up to a laying bottom level, and a foundation girder 17 is driven. Accordingly, the strength and size of the temporary standard are selected previously in conformity with aimed bearing force, thus allowing the execution of the pile having high reliability.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support column for constructing an underground section, and more particularly, to a support support column used in a reverse construction method that allows a temporary support support to be used as a permanent support support.

0002

[Prior Art] Generally, when constructing a building with a basement, the roots are first cut down to the bottom of the foundation of the entire building, and the foundation concrete for the basement, which is the lowest level, is poured, and then gradually from the basement to the ground floor. It is being constructed. This sequential construction method had the disadvantage that the construction period was long because the above-ground section had to be constructed after the underground section was constructed. Therefore, the use of reverse pouring method has been increasing recently. In the reverse driving method, foundation piles are driven in advance at predetermined locations on the ground where building columns are to be erected, and at the same time as ground floor construction is carried out on top of temporary supports erected on top of these foundation piles, root cutting and concrete pouring are carried out. The construction is carried out from the upper basement floor to the lower basement floor. At that time, a temporary support was connected to the top of the cast-in-place pile (foundation pile), and this temporary support was used as a column for the underground floor, thereby significantly shortening the construction period.

0003

[Problem to be solved by the invention] However, since forming cast-in-place piles itself takes a certain amount of time, and connecting temporary supports also requires cost, there is room for further shortening of construction time and cost reduction. there were.

[0004] The present invention has been made in view of the above circumstances, and its purpose is to provide a support support for temporary construction used in the reverse pouring method, which can further shorten the construction period and reduce costs compared to the conventional method. be.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the temporary supporting support used in the reverse driving method of the present invention is an H-shaped support that has strength dimensions that can be used as a permanent support at the pile cap of a ready-made pile. Temporary supports made of steel, steel pipes, etc. were welded together in series in advance to form a single piece, and then these were built into the pile holes. The connection between the H-shaped steel, steel pipe, etc. that will become the temporary support part and the ready-made PC pile that is the ready-made pile is such that the H-shaped steel has an anchor part that extends into the inside of the pile head of the ready-made pile. In this case, the steel pipe was welded to a pile cap ring welded to the main reinforcement, or the steel pipe was welded to a pile cap ring welded to the main reinforcement at the upper end of the ready-made pile.

[0006]

[Function] Since the temporary support section is connected to the pile cap of the ready-made pile in advance before erection, this is true not only for the reverse driving method but also for the island method, but the pile diameter and material for the temporary support section can be freely selected. Corresponds to the required supporting capacity. Then, centering and level adjustment are performed at the head of the temporary support section. While excavating the underground section, the temporary support sections will be used for permanent columns on the corresponding basement floor. Therefore, there is no need to connect the temporary support section to the new pre-fabricated pile underground.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the drawings. FIGS. 1 to 4 show temporary supports and examples of their use. The temporary supporting support column 1 illustrated here is one in which an H-shaped steel 5 for temporary support is welded in series to the head of a ready-made PC pile 3 (which may be any steel-framed reinforced concrete, reinforced concrete pipe, reinforced concrete column, etc.). This is connected in advance at the site before the PC pile 3 is erected. Details of the connection will be described later with reference to FIGS. 5 and 6. To adjust and erect this temporary supporting column 1 to the permanent column position while checking the position using a transit, first, a hole is dug vertically with an auger from the surface ground level. Once the hole has been excavated to the desired depth, inject the hardening solution while enlarging the hole, being careful not to collapse the hole wall. That is, the auger is gradually pulled up while injecting and filling the root hardening fixative 7. After the auger has been pulled out, the pile receiver is precisely aligned and installed in the center of the excavation hole using a crawler. A pile driver is placed on a pile receiver, and then a temporary supporting support column 1 for reverse driving is lifted up by a crane and gradually sunk while aligning the axial direction with the above-mentioned excavation hole.

[0008] Once the temporary support support 1 has been erected at the predetermined target position in this manner, earth and sand are excavated and removed in order to construct an underground floor. After excavating to a point slightly below the floor level of the 1st basement floor, cut the H-section steel 5 to match the floor level of the 1st basement floor using a gas welder.
The permanent steel columns 9 are connected and erected. For this purpose, a steel plate pedestal plate 11 for fixing an anchor bolt is welded and fixed to the cut surface of the H-beam 5. Further, a support member 13 for a support column is passed horizontally between H-shaped steels 5 that are temporary columns, and then a permanent steel column 9 is fixed on a pedestal plate 11. Furthermore, a beam steel frame 15 that supports the slab of the first floor above ground is connected above the main steel column 9. Next, once the soil has been excavated and removed to the floor level, the foundation beams 17 are installed. The bottom of the pile is at a level roughly equivalent to the pile cap of PC pile 3. The column reinforcement 19 whose base is embedded in the foundation beam 17 and raised above the foundation beam 17 is arranged so as to surround the H-section steel 5, and the support material 13 is removed. Furthermore, a reinforced concrete beam (RC beam) 21 for supporting the floor of the first basement floor is cast together with concrete for a steel reinforced concrete column to be cast around the outside of the H-beam 5 so as to embed the pedestal plate 11. . Column main reinforcement is also arranged around the permanent steel column 9, and it is cast integrally with the concrete around the steel frame 15 of the beam, so that the H-beam 5 of the temporary support and the permanent steel column 9 are continuous in the underground section. It constitutes the installation support.

FIG. 5 shows the connection portion between the PC pile 3 and the steel pipe 23 for the temporary support. At the pile cap of the PC pile 3, the reinforcing bars 25 are exposed, and a pile cap ring 27 is connected to the reinforcing bars, and the entire bottom end of the steel pipe 23 is welded to the pile cap ring 27. Figure 6 shows PC pile 3 and H for temporary support.
The connection portion with the section steel 5 is shown. As in the case of connecting the steel pipe 23, the pile cap ring 27 is connected to the reinforcing bar 25, and the plate 2 is welded and fixed to the bottom end of the H-beam 5.
9 are connected by welding. In addition, there is an H in the center of the PC pile 3.
An H-section steel extending downward from the plate 29 is welded and connected to the section steel 5 so as to be continuous with the section steel 5, and this is used as an H-section steel 31 for an anchor. An anchor H-beam 31 is passed through the inside of the PC pile 3, and the plate 29 is welded to the pile cap ring 27 on the pile cap of the PC pile 3.

0010

[Effects of the Invention] As described above, according to the temporary support column used in the reverse driving method of the present invention, H-beams, steel pipes, etc. that can be used as permanent columns are welded in series to the pile cap of the PC pile. Because it is connected and integrated and then built into the pile hole, it has a more reliable bearing capacity than the conventional method of driving cast-in-place piles, then driving temporary supports, and connecting them with grout etc. in the soil. It is possible to construct piles with Furthermore, the strength dimensions of the temporary support portion can be selected in advance according to the intended supporting capacity. Additionally, if the main pillar location is used as a truck pier, no temporary openings will be left and piles will not be required. Therefore, it has the effect of shortening the construction period.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the beginning of the construction procedure for using the temporary support support column of the present invention.

FIG. 2 is a cross-sectional view showing the next procedural step.

FIG. 3 is a sectional view showing the next step.

FIG. 4 is a sectional view showing the final step.

FIG. 5(a) is an explanatory diagram showing a connecting portion between a temporary support portion and a PC pile. (b) is a sectional view thereof.

FIG. 6(a) is an explanatory diagram of a connection portion between a temporary support portion and a PC pile. (b) is a sectional view thereof.

[Explanation of symbols]

１　　　Temporary support support 3 PC stake 5 H-beam steel 7. Fixative solution 9 Permanent steel column 11 Pedestal plate 13 Support material 15 Beam steel frame 17 Foundation beam 19 Column muscle 21 RC beam 23 Steel pipe 25 Rebar 27 Pile cap ring 29 Plate 31 H-shaped steel for anchor

Claims (3)

[Claims] [Claim 1] Temporary supports such as H-beams and steel pipes with strength dimensions that can be used as permanent columns are welded in series to the pile heads of ready-made piles in advance and integrated, and these are built into the pile holes. A temporary support support used for the reverse construction method, which is characterized by the following features: 2. The H-beam has an anchor portion extending into the pile cap of the ready-made pile, and is connected by welding to a pile cap ring welded and fixed to the main reinforcement at the upper end of the ready-made pile. A support post for temporary construction used in the reverse pouring method according to claim 1. 3. The temporary support support for use in a reverse driving method according to claim 1, wherein the steel pipe is welded to a pile cap ring welded and fixed to the main reinforcement of the ready-made pile at the upper end thereof.