CN2739223Y - Steel strand for prestressed concrete - Google Patents

Abstract

A steel strand for prestressed concrete belongs to ribbed steel products in prestressed concrete components for the construction industry. The utility model has the structural form that a steel wire with six spiral type arc-shaped grooves on the surface is a central core wire, six plain steel wires arranged around the central core wire are wound together tightly along the arc-shaped spiral grooves to form an engaged manner, and the diameter r of the surrounding plain steel wires equals to the radius r of the arc of the spiral type arc-shaped grooves on the surface of the central core wire. Because the central core wire and the surrounding plain steel wires are in surface contact, the mutual frictional force is increased. When steel strands are placed and stretched during the manufacture of prestressed concrete components, the utility model has the advantages of preventing the generation of slip and retraction of the central core wire, improving the integral tensile strength of the steel strand and improving the quality of prestressed concrete components.

Description

A kind of steel strand wires for prestressed concrete

Technical field

The utility model belongs to building trade with the steel strand wires of making arrangement of reinforcement in the prestressed concrete member, also can be applicable to and the solid main muscle of other materials bonded post tensioning tension.

Technical background

Making building trade with in the prestressed concrete member,, using steel wire or steel strand wires to make arrangement of reinforcement for increasing mechanical properties such as member resistance to compression, antidetonation.1 * 2,1 * 3,1 * 7 and 1 * 3I steel strand wires in standard GB/T5224-2003 " steel strand wires for prestressed concrete " are respectively standard steel section twisted wire and 3 indented steel stranded wires that indented wire is twisted into that are twisted into by 2,3,7 plain steel wires at present.

In the GB/T5224-2003 standard, 1 * 7 structural steel twisted wire particularly, be to form by 7 plain steel wire twistings, in the construction of pre-tensioning system prestressed concrete member, the plain steel wire of outside 6 torsional deflections directly contacts bonding with concrete, after steel strand tension is put concrete component is formed back pressure stress, and the light of 1 linear state circle core silk contacts with 6 straight Wiring types of plain steel wire on every side in the middle of the steel strand wires, relies on mutual frictional force that concrete component is formed indirect back pressure stress.This 1 * 7 construction standard shaped steel twisted wire is non-effective the contact because light is justified between 6 plain steel wires of core silk and outside, only rely on the back pressure stress of the frictional force generation of non-effective contact to concrete component, after the pre-tensioning system prestressed concrete member is put a steel strand wires, very easily produce SMIS silk slippage retraction, cause the minimizing of SMIS silk stress or lose stress fully.In fact steel strand wires work is 6 plain steel wires on every side, and middle heart yearn lost efficacy, and caused the whole tensile strength of steel strand wires to reduce, and stress reduces, and the concrete component performance reduces.

Summary of the invention

The utility model is mainly realized by following structure

Be a SMIS silk slippage retraction problems after overcoming 1 * 7 construction standard shaped steel twisted wire and in the pre-tensioning system prestressed concrete construction, putting, the utility model has designed a kind of employing SMIS silk surface 6 spiral circular groove shape steel wires, outside by 6 plain steel wires respectively along 6 spiral circular grooves of SMIS Steel Wire Surface steel strand wires that twisting forms that detour.

The steel strand wires of the utility model design are the SMIS silk by 1 surface with the steel wire of 6 spiral circular grooves, on every side by 6 plain steel wires respectively along in 6 spiral circular grooves of core wire closely around together, form engagement.6 spiral circular grooves of described SMIS Steel Wire Surface are to be formed by special-purpose spiral arc groove drawing mould rotation drawing manufacturing by plain steel wire.

Make the middle core wire and the ambient light round steel wire of the utility model steel strand wires, adopt to meet YB/T146 " compressor wire and steel strand wires gren rod " standard, or the wire rod that meets YB/T170 " throwing with non-steel alloy wire rod " standard is done raw material.Wire rod is purchased into factory after chemical analysis and metal lographic examination are qualified, carry out surface treatment (pickling, phosphatization, saponification, dehydrogenation) → light circle drawing (drawing 5～10 roads, total draught 〉=70%) → middle core wire helical groove drawing (compression ratio≤15%) → twisting steel strand wires (1H+6P) → stabilization processes (heating in medium frequency tempering, apply tension force, take-up) → finished product packing.This kind structural steel twisted wire mechanical property meets GB/T5224-2003 " steel strand wires for prestressed concrete " standard.Its steel strand wires nominal diameter is 9.00mm～30.00mm.Profile is seen accompanying drawing 1.

Spiral circular groove steel wire before the twisting, be the raw material wire rod after surface treatment, carry out the drawing of 5～10 passage light circle, again by special-purpose spiral arc groove drawing mould, the rotation drawing is processed into the surface with 6 parallel spiral circular grooves that detour.The direction of helical groove is left-handed or dextrorotation, decides with the twisting direction of steel strand wires.R is identical with the radius r of ambient light round steel wire for SMIS Steel Wire Surface circular groove radius of circle, and helix lead promptly is the steel strand wires lay pitch.The middle core wire before the twisting steel strand wires and the mechanical property of ambient light round steel wire should meet GB/T5223-2002 " steel wires for prestressed concrete " standard.

Description of drawings

Below in conjunction with description of drawings, accompanying drawing 1 is a kind of novel strand structure schematic diagram, and r is an ambient light round steel wire radius among the figure, that is middle core wire circular groove arc radius, and d is an ambient light round steel wire diameter, d ₀Be SMIS steel wire diameter, D ₀Be a kind of new structure steel strand wires diameter; Accompanying drawing 2 is the spiral circular groove section of steel wire of SMIS cutaway views; Accompanying drawing 3 is core wire profile schematic diagrames in the spiral circular groove.

The specific embodiment

A kind of new structure strand structure is promptly formed by twisting by 7 steel wires as shown in Figure 1, and core wire is 1 in being distributed as of steel wire, and steel wire is 6 on every side.Steel wire is the identical plain steel wire of diameter on every side, and middle core wire is the surperficial steel wire that has 6 spiral circular grooves, and r is identical with the radius r of ambient light round steel wire for its circular groove radius of circle.

Ambient light round steel wire before the twisting be by the raw material wire rod through surface treatment, carry out the drawing of 5～10 passage light circle; Middle core wire before the twisting is to rotate drawing by plain steel wire by special-purpose spiral arc groove drawing mould, makes the surface and has 6 spiral circular grooves.The middle core wire before the twisting and the mechanical property of ambient light round steel wire meet GB/T5223-2002 " steel wires for prestressed concrete " standard.

The steel strand wires twisting, the steel strand wires after the twisting should carry out continuous stabilization processes.Steel strand wires are twisted with the fingers to being generally left-hand lay, also can be right-laid.The mechanical property of a kind of new structure steel strand wires for prestressed concrete should meet GB/T5224-2003 " steel strand wires for prestressed concrete " standard.

According to theory analysis, a kind of new structure structural steel twisted wire for prestressed concrete, wherein 6 spiral radiuses are arranged is the circular groove of r on the core wire surface, it is r and the identical plain steel wire of the spiral circular groove radius r of SMIS Steel Wire Surface that 6 root radiuses are arranged on every side, form around the spiral circular groove twisting of middle core wire, in core wire be that face contacts with 6 plain steel wires on every side, increased mutual frictional force, after the making prestressed concrete member is put a steel strand wires, core wire slippage retraction in having prevented to produce, improve the whole tensile strength of steel strand wires, strengthened the performance of prestressed concrete member.

Claims (4)

1 one kinds of steel strand wires for prestressed concrete, is middle core wire by 1 surface with the steel wire of 6 spiral circular grooves, on every side by 6 plain steel wires respectively along in 6 spiral circular grooves of core wire closely around together, become the engagement shape, 6 spiral circular grooves that it is characterized in that the SMIS Steel Wire Surface are divided into left-handed or dextrorotation, decide with steel strand wires twisting direction.

2 a kind of according to claim 1 steel strand wires for prestressed concrete is characterized in that the arc radius r of 6 spiral circular grooves of SMIS Steel Wire Surface equates with 6 plain steel wire radius r on every side.

3 a kind of according to claim 1 steel strand wires for prestressed concrete is characterized in that 6 spiral circular groove helical pitches of SMIS Steel Wire Surface promptly are the steel strand wires lay pitch.

4 a kind of according to claim 1 steel strand wires for prestressed concrete is characterized in that nominal diameter is 9.00mm～30.00mm.

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