JPS62148738A - Distribution structure of shearing reinforcing steel bar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a reinforcement structure for shear reinforcing bars used as shear reinforcement in structural members such as columns and beams.

(b), Prior Art FIG. 3 is a sectional view of an r-column showing the reinforcement arrangement of conventional shear reinforcing bars.

Conventionally, in order to increase the shear resistance in the column 1, etc., as shown in FIG. In some cases, a round shear reinforcing bar 5 was provided inside, which was installed in a circular shape (including one installed in a spiral shape in a direction perpendicular to the plane of the paper in the figure). In that case, the outer circumferential portion 5a of the round shear reinforcing bar 5 and the outer circumferential portion 3a of the rectangular shear reinforcing bar 3 were generally provided in a manner that they coincided with each other.

(C) 0 Problems to be Solved by the Invention However, in this case, the opposing main reinforcing bars 2A arranged inside the round shear reinforcing bars 5, 2. The distance giL1 between the round shear reinforcement bars 5
Compared to the case where there is no column, the stress center distance of the column l becomes shorter and the stress center distance of the column l becomes smaller, resulting in the inconvenience that the performance as a cross section of the frame cannot be fully demonstrated.

In addition, in order to secure the distance L1, it is necessary to move the main reinforcement 2 in the direction of the center line xx of the column 1, but in this case, the distance L2 between the adjacent main reinforcements 2A on the left and right becomes shorter (and The distance L3 to the corner main reinforcing bars 2B was increased, making it difficult to secure an appropriate distance between the main reinforcing bars, and there was a drawback that cross-sectional performance deteriorated.

In order to eliminate the above-mentioned drawbacks, the present invention not only makes it possible to maintain the distance L1 between the opposing main reinforcements 2 to the same length as in the case without the round shear reinforcing bars 5, but also allows each adjacent main reinforcement It is an object of the present invention to provide a reinforcement structure for shear reinforcing bars that can appropriately maintain the distances glL2 and L3 between the two.

(d) Means for solving the zero problem, that is, the present invention provides
a) is provided in a shape that bulges outward with respect to the outer periphery (3a) of the rectangular shear reinforcing bar (3).

Note that the numbers in parentheses are for convenience and indicate corresponding elements in the drawings, and therefore, this description is not limited to the descriptions on the drawings. The following r (el
The same applies to the column ``, action''.

(e) 0 effect With the above-described configuration, the present invention can provide round shear reinforcement bars (5
) expands outward by eight points, its diameter (D2) expands, and the distance # (Ll) between opposing main reinforcements (2A, 2A) is changed to the distance # (Ll) between adjacent main reinforcements (2) (L2, L3). ) so that it can be expanded while maintaining it properly.

(f), Example Embodiments of the present invention will be described below based on the drawings.

Fig. 1 is a plan view of a column showing an example of the reinforcement structure of shear reinforcement according to the present invention, and Fig. 2 is a partially enlarged view showing the positional relationship between round shear reinforcement and rectangular shear reinforcement. It is.

As shown in Fig. 1, the pillar 1, which is a structural member, has a plurality of main reinforcements 2 installed in a direction perpendicular to the plane of the drawing. Shear reinforcing bars 3 are provided to connect the main bars 2. In addition, among the main reinforcements 2, the main reinforcements 2 except the corner main reinforcements 2 are provided with round shear reinforcing bars 5 formed in a circular shape to connect the main reinforcements 2A. As shown in FIG. 2, the outer circumferential portion 5a is arranged so as to be located outward from the outer circumferential portion 3a of the rectangular shear reinforcing bars 3.

Concrete 6 is poured around the round shear reinforcing bars 5, square shear reinforcing bars 3, and main bars 2 to form the outer shape of the column 1.

According to Section 10 of the Construction Standard Specifications, the cover thickness Hl of the concrete 1 and 6 for the round shear reinforcing bars 5 (see Figure 2) is 30 m if finishing is required.
m, if no finishing is required, it is specified as 40 mm, and furthermore, the cover thickness H2 for the main reinforcement 2 is usually
It is approximately 1.5 times the diameter of main reinforcement 2 (High-Strength Reinforced Concrete Design and Construction Guidelines, February 1978, Architectural Institute of Japan). Then, when the diameter of the main reinforcement 2 is determined, the reinforcement position of the main reinforcement 2 is determined. For example, if the main reinforcement 2 with a diameter D1 of 41 mm is used, the cover thickness H2 will be 1.5 x 41 = 61.5
#62 [mm]. Also, the diameter of reinforcing bar 3.5 is 1
6n+m, the distance between the outer periphery 3a of the rectangular shear reinforcing bar 3 and the column surface, that is, the cover thickness H3, is 6216
=46mm. Then, if the column 1 requires finishing, the cover thickness Hl between the outer periphery 5a of the round shear reinforcing bar 5 and the column surface should be 30 degrees, so The outer circumference 5a of the round shear reinforcement 5 can be installed in such a way that it bulges outward more than the square shear reinforcement 3 by −30=16 degrees (that is, the installation diameter D2 of the round shear reinforcement 5 is , 32n+n+ becomes larger).

The installation diameter D2 of the round shear reinforcing bar 5 is increased, and the column 1
When the main reinforcement 2A is installed in such a way that it bulges outward, the main reinforcement 2A that comes into contact with the round shear reinforcing reinforcement 5 is t! The distance L1 between the opposing main reinforcements 2A and 2A can also be expanded without reducing the distance L2 between the adjacent main reinforcements 2A and 12A.

In addition, although the above-mentioned example was described when the present invention is applied to the column 1, the present invention is not limited to the column 1, but can also be applied to other structural members such as beams. Of course.

(g) 8 Effects of the Invention As explained above, according to the present invention, the outer circumferential portion 5a of the round shear reinforcing bar 5 is replaced by the outer circumferential portion 3a of the rectangular shear reinforcing bar 3.
Compared to the reinforcement arrangement method in which the outer circumferential parts 3a15a of the round shear reinforcing bars 5 and the square shear reinforcing bars 3 are made to match, the distance between the opposing main bars 2A12A is between adjacent main bars 2A12A and 2A12
By keeping distances 1i1L2 and L3 between B at appropriate intervals, it is possible to expand to the same position as when there is no round shear reinforcing bar 5, creating a high-performance spruce cross section with a large stress center distance. can be provided.

Furthermore, since the installation diameter D2 of the round shear reinforcing bars 5 is increased, the cross-sectional area of the core portion of the column 1 surrounded by the reinforcing bars 5 can be increased, and the rigidity of the column 1 can be further increased. It becomes possible.

[Brief explanation of drawings]

Fig. 1 is a plan view of a column showing an example of the reinforcement structure of shear reinforcement according to the present invention, and Fig. 2 is a partially enlarged view showing the positional relationship between round shear reinforcement and rectangular shear reinforcement. , FIG. 3 is a sectional view of a column showing the arrangement of conventional shear reinforcing bars. 2...Main reinforcement 3...Square shear reinforcing bars 3a, 5a...Outer periphery 5...Round shear reinforcing bars Applicant Mitsui Construction Co., Ltd. Agent Patent attorney Phase 1) Shinji (1 other person)

Claims (1)

[Scope of Claims] A shear reinforcement having a main reinforcement, a square shear reinforcement provided in contact with at least a part of the main reinforcement, and a round shear reinforcement provided in contact with a part of the main reinforcement. A reinforcing structure for shear reinforcing bars, wherein the outer periphery of the round shear reinforcing bars is bulged outward relative to the outer periphery of the rectangular shear reinforcing bars.