JPH0643693B2 - On-site reinforcement method for steel pipe columns and piles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an existing steel pipe column, a steel pipe column for reinforcing a pile with concrete, and a method for on-site reinforcement of a pile.

<< Prior Art >> As is well known, for example, as a pillar member of a building structure, a reinforcing material such as a reinforcing bar is arranged inside a steel pipe, and concrete is filled to supplement the axial compressive force generated in the steel pipe. According to the steel pipe column having such a structure, the steel pipe regulates the expansion of the concrete against the load applied from the upper part of the column, so the strength against the axial load should be improved. You can

As one type of this type of steel pipe column, there is also one in which concrete prestress is introduced by tensioning a reinforcing material to fill the steel pipe. For example, Japanese Utility Model Laid-Open No. 61-204455 and Japanese Patent Laid-Open No. 62-170634 disclose. Its structure and construction method are disclosed.

By the way, if steel pipes reinforced with the concrete are used for the pillars of bridges and foundation piles of large structures that belong to the field of civil engineering, the strength can be expected to increase in the same way, but at this time, the technical problems described below there were.

<< Problems to be solved by the invention >> That is, the pillars and piles of the large structure described above have a considerably large diameter unlike the pillar members for the building structure, but these large diameters installed in advance at the construction site If all of the steel pipe is filled with concrete, the weight of the pillars or the piles themselves will become too large, and there will be a subsidence in the ground.

In order to prevent this, concrete should be cast in layers on the inner surface of the steel pipe in an amount sufficient to reinforce the steel pipe to reduce the overall weight. In order to assemble and remove the formwork, the formwork will be assembled inside the steel form and concrete will be placed in the state that reinforcing materials such as reinforcing bars are arranged in the vertical and horizontal directions along the inner surface of the steel form. It took time and labor, and there was a problem in terms of construction period and construction cost.

The present invention has been made in view of such problems, and an object thereof is to perform a reinforcing work when a concrete layer is formed on the inner surface of a steel pipe used as a pillar or a pile to reinforce the steel pipe. The purpose of the present invention is to provide an on-site reinforcement method for steel pipe columns and piles that can be performed economically and quickly.

<Means for Solving the Problem> In order to achieve the above object, the present invention provides a steel pipe column pre-installed at a construction site, a steel pipe column for reinforcing a pile with concrete, and a site reinforcement method for a pile, wherein: On the inner surface of the installed steel pipe columns and piles, a hook for locking a linear concrete reinforcing material such as a reinforcing bar or glass fiber is projected, and the concrete reinforcing material is locked to this hook. Concrete reinforcement is the steel pipe pillar,
Arrange along the inner surface of the pile, and then concrete
A concrete layer reinforced by the concrete reinforcing material is formed on the inner surface of the steel pipe pillar or the pile by spraying the inner surface of the steel pipe pillar or the pile through a nozzle inserted inside the steel pipe pillar or the pile.

<< Operation >> According to the on-site reinforcement method for steel pipe columns and piles having the above-described configuration, the concrete layer is formed only by ejecting concrete from a nozzle and spraying it, so that no formwork is required.

Further, the concrete reinforcing material can be easily arranged because it is hooked on the hook projecting in the steel pipe as the outer shell.

<Example> Hereinafter, a preferred example of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 and FIG. 2 show an embodiment of a steel pipe column and pile on-site reinforcement method according to the present invention.

The site reinforcement method shown in the figure shows an example in which a steel pipe column used as a pillar of a bridge is reinforced with reinforced concrete. A steel pipe 10 of a large diameter having a predetermined length with at least an open upper end is a construction site of the bridge. Installed in advance.

In this embodiment, the steel pipe 10 has a cylindrical cross-section and constitutes an outer shell shell as an outer formwork of a concrete layer formed inside, and the inner surface thereof is circumferentially and axially formed. A large number of hooks 12, 12, ... Which are bent in an L shape at appropriate intervals are provided in a protruding manner.

The material of the hook 12 used here is made of steel, plastic, or the like. The steel hook 12 is fixed to the inner surface of the steel pipe 10 by welding, and the plastic hook 12 is an adhesive. It is fixed.

Next, horizontal reinforcement 1 as linear concrete reinforcement
4, For example, a reinforcing rod, or a new material such as carbon fiber or glass fiber, or the like, is used as the hook 12, 12, ...
Are sequentially locked from above or below to be wound spirally along the inner surface of the steel pipe 10, that is, the outer shell.

Here, the hook 12 and the lateral reinforcing member 14 are locked by using, for example, a binding wire.

When the arrangement of the lateral reinforcing members 14 is completed, the vertical reinforcing members 16 are arranged along the inside of the lateral reinforcing members 14.

The vertical reinforcing member 16 is made of the same material as the horizontal reinforcing member 14 and is arranged at appropriate intervals in the circumferential direction.
The portion intersecting with 4 is fixed by a binding wire.

As described above, the reinforcing members 14 and 16 through the hook 12
When the arrangement is completed, the nozzle 1 is attached to the tip inside the steel pipe 10.
The concrete supply pipe 20 provided with 8 is inserted, and the concrete is injected from the nozzle 18 while rotating the concrete supply pipe 20, and the concrete is poured.

In the concrete used here, various admixtures and the like are added and mixed in order to ensure the fluidity necessary for the injection from the nozzle 18.

Then, when the concrete layer 22 having a predetermined thickness W is formed by spraying from the nozzle 18, the construction is completed.

Now, according to the method of reinforcing the steel pipe column with the concrete layer 22 formed inside the steel pipe 10 as described above, since the concrete layer is formed by spraying from the nozzle 18, the formwork installed in the steel pipe is completely eliminated. In addition, it becomes unnecessary, and in particular, since the lateral reinforcing member 14 is arranged while being sequentially wound on the hook 12 projecting from the inner surface of the steel pipe 10 and wound in a spiral shape, it can be easily and easily installed.

In addition, in the above embodiment, the case of reinforcing the steel pipe column is illustrated, but the implementation of the present invention is not limited to this,
For example, if the above-described steps are performed on the steel pipe 10 buried in the ground as a foundation pile for a large structure, it can be adopted as a reinforcing method for the steel pipe pile.

Further, the sectional shape of the steel pipe 10 may be not only circular but also rectangular.

Further, in the vertical reinforcing member 16 shown in the above-mentioned embodiment, after the necessary concrete layer 22 is formed, the end portion may be pulled to introduce prestress to the concrete layer 22.

<< Effects of the Invention >> As described in detail in the above, according to the steel pipe column and pile on-site reinforcement method according to the present invention, a large-diameter steel pipe column particularly used as a column for a large structure or a foundation pile. ， When forming a concrete layer on the inner surface of steel pipe columns and piles to reinforce the piles with concrete at the construction site, it is easy to arrange linear concrete reinforcements such as reinforcing bars and there is no need to install formwork. Thus, the steel pipe columns and piles can be reinforced economically and quickly.

[Brief description of drawings]

FIG. 1 is a perspective view showing a construction state of an embodiment of the present invention, and FIG. 2 is a top view of FIG. 10 ... Steel pipe, 12 ... Hook 14 ... Horizontal reinforcement, 16 ... Vertical reinforcement 18 ... Nozzle, 22 ... Concrete layer

Claims (1)

[Claims] 1. A steel pipe column pre-installed on a construction site, a steel pipe column for reinforcing a pile with concrete, and a site reinforcement method for a pile, wherein the pre-installed steel pipe column and the inner surface of the pile are:
A hook for locking a linear concrete reinforcing material such as a reinforcing bar or glass fiber is projected, and the concrete reinforcing material is locked on the hook to attach the concrete reinforcing material to the inner surface of the steel pipe column or pile. Then, the concrete was reinforced along with the concrete reinforcing material by spraying the concrete toward the inner surfaces of the steel pipe pillar and the pile through a nozzle inserted into the steel pipe pillar and the pile. A site reinforcement method for steel pipe columns and piles that is characterized by forming a concrete layer.