CS231330B1 - Scattered reinforcement in concrete - Google Patents

Abstract

The dispersed reinforcement for concrete, consisting of steel fibers with a cross section of 0.1 to 1 mm and provided with anchoring elements, is characterized in that the anchoring elements are formed by recesses whose direction to the longitudinal axis of the steel fiber is perpendicular, oblique or a combination of both directions.

Description

The invention relates to dispersed concrete reinforcement.

IN

Currently, concrete with scattered reinforcement consisting of steel fibers with a diameter of 0.2 to 1 mm is used. The steel fibers are evenly dispersed in the concrete mass, replacing them in smaller or larger conventional fittings. The method of anchoring - anchoring the fibers is one of the decisive conditions that ensures the correct function of the reinforcement.

There are a number of types of steel fibers which differ in shape, method of anchoring and the way of their production. These are mainly fibers produced from melt. These fibers have an irregular bumpy surface that anchors well. In the case of fibers made from steel wires having a smooth surface, they are bent, flattened and possibly fused to anchor them.

_{• The} disadvantage of bent ends is higher manufacturing effort and greater susceptibility to forming clusters, so-called hedgehogs, in the preparation of concrete mixtures. In order to eliminate this unfavorable phenomenon, the wires are bonded to bundles, which adversely affects their cost. Fibers produced directly from the melt are economically most advantageous, but for some special purposes they do not have the appropriate geometry (i.e. ratio between diameter and length. Fibers with fused ends have an ideal anchoring shape, but are more expensive to manufacture.

The above-mentioned disadvantages are overcome by the dispersed concrete reinforcement consisting of steel fibers with a cross-section of 0.1 to 1 mm2 provided with anchoring elements according to the invention. It is an object of the invention that the anchoring elements consist of recesses whose direction to the longitudinal axis of the steel filament is perpendicular or a combination of both.

The steel filament produced according to the invention is anchored in the concrete along its entire length due to the rugged corrugated surface and there is no need for further processing operations to improve the anchoring, e.g. When mixed in concrete, these fibers do not form clumps.

He did

Reinforcement was made from a starting wire 0 0.8 mm of low carbon steel in a annealed condition of 77 mm. Notches were pressed into the wire on both sides to a depth of 0.2 mm perpendicular to the longitudinal axis of the wire. The wire was subjected to bending test. The tested wire withstood 2 bends of 180 ° (r2), which guarantees appropriate mechanical properties for the application.

Example 2

Medium-carbon material was used in a state treated with 0 0.8 mm at a distance of 77 mm. Oblique indentations to a depth of 0.15 mm were pressed into the wire by forming rolls and the wire was subjected to bending test. The tested wire withstood a bend of 90 ° (r2). ,

The scattered reinforcement according to the invention is suitable for the manufacture of sleepers, airfields, panels, pressure pipes, vessels, power lines.

Claims (1)

SUBJECT OF THE INVENTION Scattered concrete reinforcement consisting of steel fibers with a cross-section of 0.1 to 1 mm and provided with anchoring elements, characterized in that the anchoring elements consist of recesses whose direction to the longitudinal axis of the steel fiber is perpendicular, oblique or a combination of both directions .