JPH083175B2 - Pile head surplus concrete treatment method for cast-in-place pile and reinforcing bar covering - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a pile head overfill concrete treatment method for cast-in-place piles and a reinforcing bar covering.

[Conventional technology]

Conventionally, in a method of constructing a cast-in-place pile by inserting a reinforcing bar cage into a hole drilled in the ground with an earth drill etc., a method of removing the concrete from the slime in the drilled hole and treating it, Means are disclosed.

Further, in this method and means, concrete can be easily separated without adhering the concrete to the reinforcing bar of the pile head,
There is also disclosed a technique in which a sleeve or the like is pre-deposited in order to save labor in removing concrete.

[Problems to be Solved by the Invention] In the above-mentioned conventional method and means, the adhesion of the reinforcing bar and the concrete of the pile head can be separated, but the concrete in the peripheral area of the reinforcing bar is hardened with a compressive force of considerable strength. Therefore, the removal work is expensive, and the treatment of excess concrete on the pile head is an important issue.

[Means for solving the problem]

This invention has been made in view of the above conventional problems,
The purpose is to prevent concrete from adhering to the reinforcing bars of the pile head, and to suppress the hardening of the concrete in the peripheral area of the reinforcing bars so that the work to remove the excess concrete can be done efficiently and labor is saved. It is intended to provide a treatment method for treating reasonably and a reinforcing bar covering used in the above method.

As a means for that, 1), before placing concrete, apply a reinforcing bar covering in which a suitable amount of sugar such as sugar water has been impregnated in a required range of the reinforcing bar of the pile head, and then place the concrete. Characterized by the pile head surplus concrete treatment method for cast-in-place piles that removes concrete from concrete pile heads, and 2), paper or cloth or synthetic resin that surrounds the outer circumference of the reinforcing bars of the pile heads. Characterized in that it is a tubular covering made of, for example, a reinforcing bar covering penetrated or filled with a sugar content such as sugar water, and 3), wherein the covering is formed in a half-split shape. In the range 2), there is a feature in the reinforcing bar coating tool, and 4), the coating tool is a material that is melted by an alkali.

[Work]

As mentioned above, the concrete of the concrete pile head is placed by placing the concrete on the reinforcing bar covering which is filled or filled with the appropriate amount of sugar at the required position of the reinforcing bar of the pile head, and after the prescribed curing period. Excessive concrete can be removed by impacting or pulling it out by mechanical means.Especially in the peripheral area of the reinforcing bar, the sugar content of the reinforcing bar covering is melted by the water content of the concrete and penetrates into the concrete. Suppresses the hardening of the concrete around it,
The problem of the conventional example is solved, for example, a considerable labor is reduced during the removing work.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 and FIG. 2 show the state of construction by the treatment method according to the present invention, in which an appropriate amount of sugar such as sugar water is previously added to the main bar a and the hoop bar b at the required position of the head of the rebar basket A. The reinforcing bar coating tool 1 --- which is impregnated with the substance is applied.

For this attachment, the outer circumference of the covering may be tied with a string or the like.

Next, the above-mentioned rebar cage A is inserted into the hole drilled in the ground with an earth drill or the like.

 Concrete is poured into this hole and cured for a certain period of time.

During this period, the underground piles remaining near the pile heads harden, while the reinforcement bar 1 attached to the required position of the head of the reinforcement cage A near the pile heads is By absorbing water and dissolving sugar, the hardening of the concrete is suppressed.

Furthermore, as shown in Fig. 2, after removing the soil until the pile head appears on the ground, the concrete on the pile head is impacted, or the pile head is properly buried for pouring. The anchors (not shown) may be lifted to remove the concrete from the pile heads so that the main bars a and the hoop bars b can partially project.

FIG. 3 shows a reinforcing bar covering used when the above treatment method is applied. In the figure, (a) shows a hollow one, and (b) shows a C-shaped cross section with a part cut. In addition, (C) shows a form in which it is divided into two parts, and each has an appropriate amount of sugar content such as sugar water infiltrated therein. As another embodiment of this reinforcing bar covering, it is also easily inferred from the present invention that the bag is formed of a water-permeable cloth or paper and the bag is filled with sugar particles or powder. obtain.

Further, it can be easily inferred from the present invention that the material of the main body used for the reinforcing bar covering is one that is melted by the alkali in the concrete when the concrete is poured.

〔The invention's effect〕

As described in detail above, according to the pile head overfill concrete treatment method for cast-in-place piles and the reinforcing bar covering tool of the present invention, the workability of installing the reinforcing bar cage at the required head position is simple and easy. Is effective in improving concrete strength, especially when water is poured into concrete to dissolve a suitable amount of sugar in the reinforcing bar covering tool to minimize the adhesive force or bonding force with the concrete in the vicinity, and further reduce concrete strength. In addition, the pile head surplus concrete can be removed easily and easily, labor saving and rationalization of pile head treatment is expected, and practically useful pile head surplus concrete treatment and reinforcing bar covering can be obtained. Is.

[Brief description of drawings]

FIG. 1 and FIG. 2 are construction state diagrams by the method of the present invention and a reinforcing bar covering, and FIGS. 3 (a), (b) and (c) show examples of the reinforcing bar covering, respectively. A: Reinforcing bar cage 1 ... Reinforcing bar covering

Claims (4)

[Claims] 1. Before concrete is poured, concrete is cast by applying a reinforcing bar covering in which a proper amount of sugar content such as sugar water is permeated or filled in a required range of the reinforcing bar of the pile head, and thereafter. A method for treating pile head surplus concrete of cast-in-place pile, characterized by removing concrete. 2. A covering made of paper, cloth, or synthetic resin, which surrounds the outer periphery of the reinforcing bar of the pile head, within the required range, and which is impregnated or filled with a sugar component such as sugar water. A reinforcing bar covering device characterized by the above. 3. The reinforcing bar covering device according to claim 2, wherein the covering device is formed in a half-split shape. 4. The reinforcing bar coating device according to claim 2 or 3, wherein the coating device is made of a material that is soluble in alkali.