JP2002309712A - Polygonal twisted reinforcement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polygonal twisted reinforcement 1 for compensating for the defect, preventing human and physical damage and a danger by separation and falling of concrete, restraining peeling-off for a while for a period up to a periodic inspection even if a crack 4 is caused, and securing safety with an allowance for months and days for detection and repairing by solving remote causes of being inferior in adhesion of a horizontal lower half 3 more than a horizontal upper half 2 of the reinforcement due to a cause of a bleeding phenomenon and improper curing, easily forming a feeble cavity part 9 in the horizontal lower half 3 of the reinforcement over the whole extension, deteriorating the adhesion by the feeble cavity part 9, and separating and dropping the concrete by a crack 10 and the expansion. SOLUTION: This polygonal twisted reinforcement 1 is devised as a solving means so that the reinforcement is formed in a polygonal shape, and when applying a twist, respective cross-sectional shapes of the horizontal upper half 2 and the horizontal lower half 3 of the reinforcement are continuously deformed at a specific interval, and the feeble cavity part 9 generated in the horizontal lower half 3 of the reinforcement becomes uneven and minimum over the whole extension.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polygonal torsion reinforcing bar 1.
The strengthening of the adhesive force between the concrete and the concrete 5 helps prevent the risk of concrete peeling and falling, and can be effectively used in various concrete 5 structures.

[0002]

2. Description of the Related Art A round bar steel deformed steel bar 6 is used as a steel bar for a reinforcing bar.
Can be expected to have a normal adhesive force, but the lower horizontal half 3 has a reduced adhesive force due to various phenomena during the period from the start of concrete casting to hardening. In this case, appropriate curing is unavoidable, and in this case, the horizontal upper half 2 of the round steel bar deformed steel bar 6 becomes an obstacle, and a weak hollow portion 9 is formed in the horizontal lower half 3, resulting in insufficient adhesion, cracks 10 and concrete. It is a distant cause of peeling.

[0003]

This has the following disadvantages. (B) Around the horizontal lower half 3 of the rebar, the horizontal upper half 2 becomes an obstacle, and a weak cavity 9 is generated due to the floating water 7, the latence 8, inappropriate curing of the concrete 5 during hardening and shrinkage of the concrete, and the like. There is a difference in the adhesion between the horizontal upper half 2 and the horizontal lower half 3 of the reinforcing bar. (B) The weak cavity 9 contributes to the crack 10 due to repeated vibration, expansion of reinforcing steel rust, and the like. (C) If the cracks 10 are formed in the concrete 5, the concrete 5 peels and falls, causing physical damage and human danger.

[0004]

Means for Solving the Problems A polygonal surface is formed to minimize the weak hollow portion 9 of the horizontal lower half 3 of the rebar caused by breathing phenomena or inappropriate curing, etc., and the rebar is constantly twisted at regular intervals. The cross section of the horizontal upper half 2 and the horizontal lower half 3 is changed to prevent the concrete 5 from wrapping around the polygonal torsional reinforcing bar 1 to prevent a decrease in adhesive force, and to use a polygonal torsional reinforcing bar 1 as a solution.

[0005]

Embodiments of the present invention will be described below. (A) Since the tensile strength of the reinforcing bar is determined by the cross-sectional area and the adhesion strength is determined by the outer peripheral length, the diameter of the reinforcing bar is emphasized in the design and construction stages. If the cross-sectional area and the outer peripheral length of the polygonal torsion reinforcing bar 1 are the same diameter, Although it is disadvantageous to use, polygonal torsion reinforcing bar 1
If the circumscribed circle is made larger by about 2 mm and then the obtuse angle portion of the polygonal torsion bar 1 is compressed by about 1 mm, the cross-sectional area and diameter become substantially the same as those of the conventional bar, and there is no significant change in the design and construction. (B) The weak cavities 9 in the horizontal lower half 3 of the reinforcing bar, which are caused by the breathing phenomenon or inappropriate curing, etc., are also generated uniformly and over the entire length like the weak cavities 9 of the round bar 6 and the deformed bar 6. However, the use of the polygonal torsion bar 1 results in a non-uniform and small portion, which leads to a reduction in the cause of the crack 10.

[0006]

This has the following effects. (A) The polygonal torsion reinforcing bar 1 increases the adhesive force of the lower horizontal half 3. (B) The polygonal torsion bar 1 reduces the cause of the crack 10. (C) The torsion surface of the polygonal torsion bar 1 increases the pull-out resistance due to the torsion surface. (D) The polygonal torsion reinforcing bar 1 is effective even when used as a vertical reinforcing bar.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of various types of torsion of the present invention.

FIG. 2 is a top plan view of the present invention.

FIG. 3 is a side view of the present invention.

FIG. 4 is a detailed view of the obtuse compression section of the present invention.

FIG. 5 is a sketch drawing of reinforced concrete of a weak hollow portion 9 generated during a breathing phenomenon or the like according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polygonal torsion bar 2 Horizontal upper half 3 Horizontal lower half 4 Compressed part of obtuse angle 5 Concrete 6 Round steel bar deformed steel bar 7 Floating water 8 Laitance 9 Weak cavity 10 Crack

Claims (1)

[Claims] 1. The polygonal torsion reinforcing bar 1 mainly strengthens the adhesive force between the lower horizontal half 3 of the reinforcing bar and the concrete 5,
A polygonal torsion reinforcing bar 1 for preventing cracks 10 in the concrete 5 and peeling and falling of the concrete 5 due to expansion.