SU1527402A1 - Bed for making prestressed ferroconcrete structures - Google Patents

Abstract

The invention relates to the field of construction and can be used in the manufacture of core and beam structures for bridges, buildings and other structures. The aim of the invention is to increase reliability. The stabilizer 9 forces in the form of elastic elements with closing switches are introduced into the design of the stand. The stabilizers 9 are arranged between the supporting structure 1 and the end stops 2, and can also be located between the end stops 2 and the latch 6 or the hydraulic jacks 7. In the latter case, they have a distribution plate. 8 il.

Description

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Stand with stabilizers effort works as follows.

The reinforcing elements 3 are secured in the gripping devices 4, with the clips 6 tightened on the rods 5 and fixed on the tension yoke 8. By activating the jacks 7, the force of the tensioned reinforcement 3 in the stand shown in FIG. 1 is transmitted through the end supports 2 to the stabilizers 9 and the supporting structures 1. At 10 a force equal to (0.9-0.95) L, the elastic elements 14 of the stabilizers 9 are released (by turning the nut) from the tightening effect of the strain relief devices and At this point, when the force is increased to NHK, they are deformed together with the entire stand system. The created (initial) tension force L is fixed by various threaded latches on the end stop 2 (Fig. 1) or on the distribution plate 10 (Fig. 2).

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The invention relates to the construction and can be used in the manufacture of core and beam structures for bridges, buildings and other structures.

The purpose of the invention is to increase reliability.

FIG. 1 shows an stand of the distance type, general view; in fig. 2 shows section A-A in FIG. one; in fig. 3 - stand of the spacer type, general view; in fig. 4 shows a section BB in FIG. 3; in fig. 5-8 - constructive schemes of stabilizers efforts.

The stand consists of supporting structures 1 and end stops 2, which receive the force from tensioning reinforcing elements 3, which are anchored at the ends in the gripping devices 4 through inventory rods 5, fixed on the stand with threaded fasteners 6. For tensioning reinforcing elements, jacks 7 and tension bar 8. Stabilizers 9 forces are arranged (mainly with ball bearings) between the support structure 1 and the end stops 2 (Fig. 1), and can also be located

between the end stops 2 and the latch 6 g to the deformation catcher and the surface is stabilized by hydraulic jacks 7 (Fig. 2). In the final force 9 there is a gap sufficient

In this case, they have a distribution plate 10. The product 11 in the heated formwork 12 is on the pallet 13.

The force 9 stabilizer (fig. 5) consists of staples (thin and wide) elastic elements 14 connected between the co. battle hinges 15.

The force stabilizer may consist of elastic elements 14, such as springs, expanded, fixed and fixed between rigid plates 16 (Fig. 6). Here is a variant of a single end stabilizer located on the inventory tag 5 between the end stop 2 stands and latch 6.

The stabilizer force can be made of elastic elements 14, pairwise connected at the ends by hinges 15 (Fig. 7). Between the pair of elastic elements of the time. South rigid fixed pads 17. The number of pair of elastic elements may be different.

In addition, the stabilizer forces can be made of elastic elements 14 and the rods 18, interconnected by hinges 15.

/ 1l increase rigidity of the stand at

tensioning reinforcement stabilizers 9 have 50 anchors), dragging it with them into joint strain reliefs (not indicated), deformation. As a result of this, the snapping elastic elements 14 are in a deformed state under the influence of a force that makes up 90-95% of the total force controlled by the tension of the beams (Lchk). When choosing a constructive 55 scheme of stabilizers 9 efforts should take into account their dimensions along the length of / (along the facade of the stand) and along the width b (in terms of the stand).

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In the working position, the stabilizers 9 forces are in the deformed stress state and are released from the buckle deformations. Between the nut on the concept of further work of the elastic elements 14.

After installation of the reinforcement cage of the product And and the heaters of the formwork 12 on the pallet 13 of the stand, the concrete mix is laid. From this moment, under the influence of the temperature of the concrete mixture being laid, as a rule, exceeding the temperature of the stand, and the even higher temperature of the concrete during the heat treatment of the tension on the cold bench, the reinforcement heats up and therefore it would have to decrease the voltage, i.e. temperature tensions under 40 conditions of complete (or almost complete) absence of adhesion to concrete. However, this does not occur, because the elastic elements 14 of the stabilizers 9, the force, as it were, “follow what is happening and, reinforcing the reinforcement, do not allow a noticeable decrease in the force in it. Subsequently, with an increase in the temperature of the product and an increase in the adhesion of the reinforcement to the concrete gaining strength, the product, heating and lengthening, captures the reinforcement (especially for internal

In the areas of the reinforcement (behind internal anchors), a decrease in the tension of the latter should have taken place, and in concrete there should be a compressive force. But this does not happen, because stabilizers 9 efforts, continuously reinforcing reinforcing elements, relieve concrete that is not yet strong, from the adverse effect of compressive forces.

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Stand with stabilizers effort works as follows.

The reinforcing elements 3 are secured in the gripping devices 4, with the clips 6 tightened on the rods 5 and fixed on the tension yoke 8. By activating the jacks 7, the force of the tensioned reinforcement 3 in the stand shown in FIG. 1 is transmitted through the end supports 2 to the stabilizers 9 and the supporting structures 1. When the force is equal to (0.9-0.95) L, the elastic elements 14 of the stabilizers 9 are released (by turning the nut) from the tightening effect of the strain relief devices and from this At the moment of increasing force to NHK, they are deformed together with the whole stand system. The created (initial) tension force L is fixed by various threaded latches on the end stop 2 (Fig. 1) or on the distribution plate 10 (Fig. 2).

 the strainer and the surface of the stabilizer 9 force there is a gap sufficient

In the working position, the stabilizers 9 forces are in the deformed stress state and are released from the buckle deformations. There is a gap between the nut on the windings of the strainer and the surface of the stabilizer 9, there is a sufficient gap.

for further work of the elastic elements 14.

0 anchors), taking her along with you to joint deformation. As a result of this,

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After installation of the reinforcement cage of the product And and the heaters of the formwork 12 on the pallet 13 of the stand, the concrete mix is laid. From this moment, under the influence of the temperature of the concrete mixture being laid, as a rule, exceeding the temperature of the stand, and the even higher temperature of the concrete during the heat treatment of the tension on the cold bench, the reinforcement heats up and therefore it would have to decrease the voltage, i.e. temperature loss of tension in 0 conditions of complete (or almost complete) absence of adhesion with concrete. However, this does not occur, because the elastic elements 14 of the stabilizers 9, the force, as it were, “follow what is happening and, reinforcing the reinforcement, do not allow a noticeable decrease in the force in it. Subsequently, with an increase in the temperature of the product and an increase in the adhesion of the reinforcement to the concrete gaining strength, the product, heating and lengthening, captures the reinforcement (especially for internal

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anchors), carrying her with you to joint deformation. As a result, at the free (behind internal anchors) areas of reinforcement there should have been a decrease in the tension of the latter, and in concrete there should be a compressive force. But this does not happen, because stabilizers 9 efforts, continuously reinforcing reinforcing elements, relieve concrete that is not yet strong, from the adverse effect of compressive forces.

At the stage of cooling the product, the process takes place in the opposite direction. At the same time, in the free tail areas of the reinforcing elements (to the inner anchors), as a result of the reduction of the cooling product in the zone between the inner anchors, the forces in the reinforcement would have to increase. But this does not happen due to the positive role of stabilizers 9 efforts that impede this process.

Thus, the negative phenomena, which are involved in the process of fabrication and overly stressed reinforced concrete structures in the stand, will be substantially eliminated. Calculations show that the magnitude of the tension loss of reinforcement and force on concrete of an early age as a result of

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stabilizers can be reduced by 7-10 times or more.

Claims (1)

Invention Formula (a tendency for the manufacture of prestressed reinforced concrete structures containing a base with end supports, a tension block with gripping devices, clamps, a tension beam and hydraulic jacks, a pallet and heated formwork, characterized in that, in order to increase the reliability, it equipped with stabilized | 1a: .1 and force, installed at both ends of the stand between the stops and clamps, with the aforementioned stabilizers emitted in the form of elastic elements with closures. / 2  ///// r 1 Phage.L / / Phage. H Fig.b i 15 Fi2.7