SU1636545A1 - Spiral anchor for prestressed reinforcement - Google Patents

Abstract

This invention relates to the production of prestressed reinforced concrete. In order to increase the bearing capacity of the anchor on the reinforcement, a spiral sleeve is fixed by means of crimping, the end coils of the wire of which are made with an oblique cut at an angle of 30-60 & to the axis of the wire. 2 ill., 1 tab.

Description

The invention relates to the production of prestressed reinforced concrete and can be used as a temporary end anchor on rebars.

The aim of the invention is to increase the carrying capacity of the anchor.

FIG. 1 shows a spiral anchor with a completely filled metal bearing end; in fig. 2 - anchor blank - spiral bushing with kosig, cut end of the end coil.

The spiral anchor contains 1 spiral sleeve 2 fixed on the reinforcement, having an oblique shear section of the winding3 at an angle of 30-60 ° to the axis of the wire of spiral sleeve 2.

To form spiral anchors on reinforcing bars 1 used in prestressed reinforced concrete, spiral sleeves 2 made of rolled steel with a diameter of 6 are used; 6.5; eight; ten; 12 mm. The range of prestress rod steel 1, depending on the level of mastering of the technology, is within the diameters of 10-22 mm.

The checks confirmed the dependence of the cut-off angle of the end coils 3 of the spiral sleeve 2 on the diameter of the crimped wire and the diameter of the core reinforcement 1:

tga-2

where a. - the angle between the plane of the cut 3 of the reference turn of the anchor and the axis of the wire of the spiral sleeve 2;

d is the diameter of the wire forming spiral sleeve 2;

D - diameter of bar reinforcement 1.

All actual and theoretically possible combinations of the diameters of the wire of the sleeves 2 and the reinforcement 1 (see table) are subject to this dependence.

The table shows practical options for the combination of wire diameters and reinforcement.

The compression of the anchors is carried out as follows.

On the rod 1 put the spiral sleeve 2, having an oblique slice of coil 3, and place it in the nests of the pressing jaws of the press or crimping machine (not shown).

about ate

four

cl

on), after which they turn on the compression mechanism and compress the anchor.

When this occurs, plastic deformation and tightness of the turns of the spiral sleeve 2 on the corrugated surface of the reinforcing bar 1 and the anchor end 4 of the anchor are filled with metal completely without gaps due to the deformation of the pointed end 3 of the cut of the first turn in the transition to the second turn.

Ф орм ул а and з о б р ё te n and

Spiral anchor for prestressing reinforcement including spiral

a sleeve fixed to the reinforcement by means of compression, characterized in that, in order to increase the bearing capacity of the anchor, the end coils of the wire of the spiral sleeve are made with an oblique cut

at an angle of 30-60 ° to the axis of the wire.

Note. In the numerator - and in the denominator - tg a,

FIG. 2

E0-b #

Claims (1)

Claim Spiral anchor for prestressed reinforcement, including a spiral 5 sleeve, fixed to the reinforcement by crimping, characterized in that, in order to increase the bearing capacity of the anchor, the end coils of the spiral wire are made with an oblique cut 10 at an angle of 30-60 ° to the axis wire. The diameter of the rods, mm The cutting angle of the end turns of the anchor with a wire diameter, mm 6 6.5 8 10 12 10 fifty 1,2 52 1.3 58 1,6 - - 12 45 1.0 47 55 59 • - 1,083 1.3332 1,666 14 40 42 48 55 59 0.857 0.928 1.1428 1.4284 .. 1.7142 16 36 0.75 39 0.812 45 1,0 51 1.25 56 1.5 18 33 35 41 48 53 0.6666 0.722 0.888 1.11 1.332 20 thirty 0.6 33 0.65 38 0.8 45 1.0 fifty 1.2 22 - 36 42 47 0.7272 0.909 1.0908 25 - - 32 0.64 38 0.8 .... 43 0.96 28 - - - 35 40 0.714 0.856 32 - - - - 36 0.75 36 . - 33 -ULSS Note. In the numerator, a; in the denominator - tg a. Figure 2 Compiled by V. Gerasimov Editor I. Shmakova Tehred M. Morgenthal Corrector S. Shekmar Order 801 Circulation 419 Subscription VNIIIPI of the State Committee for Inventions and Discoveries. Under the State Committee for Science and Technology of the USSR 113035, Moscow, Zh-35, Raushskaya nab., 4/5 Production and Publishing Combine Patent, Uzhgorod, 101 Gagarin St.