SU953153A1

SU953153A1 - Apparatus for thermal tensioning of reinforcement

Info

Publication number: SU953153A1
Application number: SU802996774A
Authority: SU
Inventors: Игорь Иванович Кравченко; Соломон Борисович Годзданкер
Original assignee: Витебский Домостроительный Комбинат
Priority date: 1980-10-23
Filing date: 1980-10-23
Publication date: 1982-08-23

Description

(54) УСТРОЙСТВО ДЛЯ ТЕРМИЧЕСКОГО НАТЯЖЕНИЯ(54) DEVICE FOR THERMAL TENSION

АРМАТУРЫFITTINGS

1one

Изобретение относитс к способам электротермического нат жени арматуры при изготовлении предварительно напр женных железобетонных конструкций на заводах промышленности строительных материалов.The invention relates to methods of electrothermal tensioning of reinforcement in the manufacture of prestressed concrete structures at plants of the building materials industry.

Известен способ нат жени арматуры, включаюш.ий электротермическое нагревание соединенных с арматурой т говых стержней , фиксацию их в нагретом удлиненном состо нии и последующее охлаждение с нат жением арматуры, причем нагревание и охлаждение т говых стержней осуществл етс циклично, при этом после охлаждени т говых стержней в конце каждого цикла арматуру фиксируют в удлиненном состо нии 1.There is a known method of tensioning the reinforcement, including electrothermal heating of the connecting rods connected to the reinforcement, fixing them in a heated elongated state and subsequent cooling with tensioning the reinforcement, and the heating and cooling of the connecting rods is carried out cyclically; rods at the end of each cycle, the reinforcement is fixed in an elongated state 1.

Недостатком способа вл етс мала величина нат жени арматурных стержней за один цикл нагрева т говых стержней, что вызывает необходимость производить несколько циклов нагрева-охлаждени т говых стержней.The disadvantage of this method is that the tension of the reinforcing rods is low during one cycle of heating the heating rods, which makes it necessary to perform several heating-cooling cycles of the trailing rods.

Наиболее близким техническим решением к предлагаемому вл етс устройство дл фиксации и группового спуска нат жени арматурных элементов, содержащее поддон, подвижный и неподвижный упоры.The closest technical solution to the present invention is a device for fixing and group descent of the reinforcing elements, comprising a pallet, movable and fixed stops.

т ги, подвижную траверсу, т говый стержень , фиксаторы 2.gi, movable traverse, pull rod, clamps 2.

Недостатком устройства вл етс сложность и больша металлоемкость конструкции .The disadvantage of the device is the complexity and high intensity of the structure.

5Цель изобретени - повышение производительности устройства.5 The purpose of the invention is to improve the performance of the device.

Цель достигаетс тем, что в устройстве дл термического нат жени арматуры, включающем поддон, подвижный и непод Q вижный упоры, т ги, подвижную траверсу, т говый стержень, фиксаторы, т говый стержень выполнен со съемной головкой из материала , обладающего термической пам тью. На фиг. 1 и 2 представлен вариант исполнени устройства соответственно передThe goal is achieved by the fact that in the device for thermally tensioning the reinforcement, including a pallet, a movable and sliding Q, fixed stops, drawbars, a movable traverse, a pull rod, retainers, and a pull rod are made with a removable head from a material with thermal memory. FIG. 1 and 2 show an embodiment of the device, respectively, before

15 началом и в конце цикла нат жени арматурных стержней; на фиг. 3 - деталь соединени т гового стержн со съемной головкой; на фиг. 4 и 5 - вариант исполнени т гового стержн в двух положени х, соответственно перед началом и в конце нат жени арматурных стержней.15 beginning and at the end of the tensioning cycle of reinforcing bars; in fig. 3 - detail of the connection of the traction rod with a removable head; in fig. 4 and 5 — an embodiment of the pull rod in two positions, respectively, before the beginning and at the end of the tension of the reinforcing bars.

Claims

The device for thermally tensioning reinforcement contains movable 1 and fixed 2 gripping crossbars for tensioned reinforcing bars 3, draw rods 4 and fixed stops 5, detachable elements 6, clamps 7 and 8 placed on draw bars x 4. Fixed cross bar 2 and stops 5 are rigidly fixed. The pull rod can also be made composite (Figs. 4 and 5) and consist of clamps 7 and 8 and a section made in the form of a hollow rod with a head 9. The device works as follows. The tensioned reinforcement 3 is fixed in the cross-arms 1 and 2. The clamps 7 move on the pull rods and are set at a predetermined distance a from the fixed stops 5 equal to the design length (elongation) of the tension rods 3. Thereafter, one is heated known methods for parts of the device, made of titan-nickel alloy. When these parts reach 70 ° C or more, they "recall their original shape, i.e., the force elements 6 are straightened and bent mirrorwise in the opposite direction and the hollow rod 9 becomes barrel-shaped. As a result, the movable yoke 1 is moved to the design value A up to the stop by the clamps 7 into the fixed stops 5, which ensures a predetermined tension value of the reinforcing rods 3. After that, the clamps 8 placed on the traction rods on the other side of the stops 5, bring up to the last closely and thereby fix the reinforcing rods 3 in the tensioned state. Then, the heating of the force elements 6 and the hollow rod 9 is stopped and further technological operations are carried out on the mold to form the concrete product. The implementation of a pull rod 4 with a T-shaped removable head allows to reduce the consumption of a nickel-titanium alloy in the production of tension fittings for a group of products. To do this, after tensioning the reinforcement on one product after fixing the traction rod 4 with the clamp 8 in the tensioned position, the head is removed (after it is cooled) by slightly moving along the rod 4 and rotating by 90 ° (Fig. 5), transferred and installed in a similar way on traction device of another form. Claims An apparatus for thermally tensioning an armature, including a pallet, a movable and fixed anvil, a pull, a movable traverse, a pull rod, retainers, characterized in that, in order to improve the performance of the device, the pull rod is made with a removable head made of a material with thermal memory. Sources of information taken into account in the examination 1. USSR author's certificate number 672313, cl. E 04 G 21/12, 1978.

2. USSR author's certificate number 332193, cl. E 04 G 21/12, 1970 (prototype).

Fig.Z

ig.5