JPH07119499B2 - Synthetic flash - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite beam having a reinforced concrete structure (referred to as an RC structure) built in a web portion between flanges of H-section steel.

[0002]

Problems to be Solved by the Invention As shown in FIGS.
In the web portion between the flanges 2 and 2 of the H-section steel 1, the main bar 3,
Synthetic burrs having an RC structure reinforced with ribs 4 or an RC structure reinforced with main bars 3 and vertical bars 5 have been put into practical use. By incorporating an RC structure in these conventional synthetic burrs, rigidity, proof stress, etc. can be improved, but they have a problem that they are heavier than steel beams and have a long span, which is difficult.

The present invention has been made in view of the above problems. The purpose is to propose a synthetic beam that is relatively lightweight, has a large yield strength, and enables a long span.

[0004]

This composite beam is a composite beam in which a reinforced concrete structure is built between flanges of an H-shaped steel, and the reinforced concrete structure built-in portion is provided at both beam end portions and a central portion, and both beam end portions. It is characterized in that a tension material is arranged between the flanges between them to introduce prestress.

[0005]

This composite beam is made lightweight by incorporating the RC structure only in the central portion and both end portions which require relatively large rigidity and proof stress. By introducing pre-stress with a tension material, it is possible to increase the proof stress, and in combination with the weight reduction, it is possible to extend the span. Further, the RC structure portions built in the central portion and both end portions hold the tendon and contribute to the introduction of prestress by the tendon.

[0006]

EXAMPLE The composite flash of the example shown in FIG. 1 has both ends of an H-shaped steel 1 joined to columns 6 and RC structure portions 7a and 7b are provided at the center and both ends thereof, and two RC members are provided between both ends. Alternatively, it is constructed by arranging several PC steel wires 8.

Each of the RC structure parts 7a and 7b has four or several main bars 3 and stir bars 4 arranged between the upper and lower flanges 2 and 2 on both sides of the web of the H-shaped steel 1 as shown in FIG.
Concrete 9 is filled, and stiffeners 10 shown in FIG. 3 are fixed to both ends thereof. Each PC steel wire 8 is shown in Figs.
4, the RC structure 7a, 7b and the through hole 11 of the stiffener 10 are passed along both sides of the web of the H-section steel 1, and both ends thereof are fixed and arranged on the surface of the outer stiffener 10 of the RC structure 7b. After the concrete 9 is hardened, prestress is introduced.

Although the main reinforcement 3 and the stirrup 4 are arranged in the RC structure, the main reinforcement is not necessary when only increasing the rigidity.

[0009]

The present invention is as described above. Despite the fact that this composite beam is relatively lightweight, the central portion and both end portions, which are required to have high rigidity, have a built-in RC structure and are reinforced to have a large yield strength. Therefore, local buckling of the H steel is suppressed, and prestress is introduced between both ends by a tension material, so that a long span can be achieved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a composite beam according to an embodiment.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a sectional view taken along line CC of FIG.

FIG. 5 is a sectional view of a conventional composite beam.

FIG. 6 is a sectional view of a conventional composite beam.

[Explanation of symbols]

1 ... H-section steel, 2 ... Flange, 3 ... Main bar, 4 ... Stirrup bar,
5 ... Vertical stripes, 6 ... Pillars, 7a, 7b ... RC structure, 8 ... PC
Steel wire, 9 ... Concrete, 10 ... Stiffener, 11 ... Through hole.

Claims (1)

[Claims] 1. In a composite beam having a reinforced concrete structure embedded between flanges of H-section steel, the reinforced concrete structure built-in portion is provided at both ends and the center of the beam, and a tension member is provided between the flanges between the ends of the beam. A synthetic burr characterized by being stiffened and prestressed.