JPS6035508B2 - Shear reinforcement method for openings in reinforced concrete members - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for shear reinforcing a closed part of an already constructed reinforced concrete member of a structure such as a building.

Generally, when a wall material with a closed part is subjected to an external force, stress concentration occurs around the closed part. For example, when an elastic infinite plate with a circular hole is subjected to a uniform shear force, the circular hole The diagonal tension at the edge reaches four times that at a position sufficiently far from the circular hole.

For this reason, when providing a through hole that is a closed part for equipment piping such as a reinforced concrete beam member in the structure of a building, it is recommended to position the through hole near the center of the span where shear force is particularly low. In addition to taking this into account, it is common practice to provide necessary reinforcement against diagonal tension around the temporary frame that forms the opening using reinforcing bars, steel plates, etc. before pouring concrete. However, after constructing a reinforced concrete member, it often becomes necessary to change the position of the closed part or create a new opening due to changes in equipment or the like. The present invention provides a method that can effectively and reliably perform shear reinforcement of the closed section when an open section is provided in the above-mentioned already constructed reinforced concrete member.

The following is a shear reinforcement method for a closed part provided in a reinforced concrete section according to the present invention, as illustrated in FIGS. A slightly larger transverse hole 4 is drilled with a slight inclination to match the outer shell of the reinforcing steel pipe 3, the reinforcing steel pipe 3 is inserted into this transverse hole 4, and then a hole is inserted between the perforating hole 4 and the reinforcing steel pipe 3. The feature is that a strong adhesive 5 is injected into the small gap from the upper side of the slope of the through-hole, and is filled and fixed to the reinforced steel pipe concrete 2 integrally.

In addition, in the drawing, 6 indicates the main reinforcement of the reinforced concrete member. Therefore, in drilling the above-mentioned horizontal through hole, the position of the horizontal through hole is naturally set at a place where the shearing force is as small as possible, and the opening is determined to be as small as possible. Next, as the above-mentioned strong adhesive 5,
Epoxy resin, unsaturated polyester resin, etc. are used. Further, the reinforcing steel pipe 3 resists diagonal tension caused by shearing force, and a thick steel pipe is used for this purpose. The method of the present invention is carried out as described above, and the closed part of the reinforced concrete member is formed by a reinforcing steel pipe 3 inserted into a horizontal through hole 4, and a strong adhesive 5 filled with a reinforcing steel pipe 3 injected between the two.
The penetrating hole 4 is integrally fixed to the concrete 2 by
At the same time, it effectively resists diagonal tension caused by shear force, and effectively and reliably reinforces the spout of a reinforced concrete member.

In addition, in the method of the present invention, a slightly larger through hole 4 is drilled with a slight inclination to match the outer shape of the reinforcing steel pipe 3 using a drilling machine such as a drill, so that the through hole 4 and the iron A strong adhesive 5 is placed between the reinforcing steel pipe 3 to be inserted.
A small gap suitable for injection and filling is formed with a slight slope.Since the small gap is slanted, it is easy to inject the viscous strong adhesive into the small gap from the upper side of the slope as it flows down. This method has the advantage that it is reliable, the amount of expensive strong adhesive used can be reduced to the required amount, and the reinforcing steel pipe can be firmly and reliably fixed integrally to the concrete 2.

[Brief explanation of drawings]

The attached drawings are for explaining aspects of the method of the present invention by examples, and FIG. 1 is a front view of the gateway of a reinforced concrete member in which the method of the present invention was applied, and FIG.
It is a longitudinal cross-sectional view along the A line. 1... Reinforced concrete member, 2... Concrete, 3... Reinforced steel pipe, 4... Penetration horizontal hole,
5... Strong adhesive, 6... Main reinforcing bar. Figure 1 Figure 2

Claims (1)

[Claims] 1 Using a drilling machine, use a drilling machine to drill a slightly larger through-hole at a slight angle at a slight angle to match the outline of the reinforcing steel pipe as described below, at the required location in the reinforced concrete member that has already been constructed in the structure, and insert the reinforcing steel pipe into this through-hole. and then inject and fill a strong adhesive into the small gap between the horizontal through hole and the reinforcing steel pipe from the upper side of the slope of the horizontal through hole to integrally fix the reinforcing steel pipe to the concrete. Shear reinforcement method for openings in