SU771269A1 - Butt joint of prefabricated ferroconcrete columns - Google Patents

Description

one

The invention relates to the field of construction, namely to the structures of the joints of prefabricated reinforced concrete columns of buildings and structures.

A butt joint of precast reinforced concrete columns is known, including interconnecting outlets of working reinforcement and welded-in concrete surfaces at the point of contact. Hinging surfaces at the junction is performed by simultaneously cutting two ends of the connected elements 1.

The disadvantage of this joint is the low rigidity and the impossibility of obtaining a complete match of the surfaces of the ends of the abutting elements.

A butt joint of precast reinforced concrete columns is known, having outlets of longitudinal reinforcement and flattened ends of the ends of the elements to be joined. Pads attached to the ends of the reinforcing bars of each of the adjacent elements are interconnected in junction 2.

The disadvantage of such a joint is the high consumption of metal.

A butt joint of prefabricated reinforced concrete columns of industrial tasks, coupled with welded surfaces, is known, including corner and intermediate reinforcement outlets, located 5 in monolithic grooves 3.

The disadvantage of this connection is the complexity of installation, since the lifting mechanism must keep the top column above the bottom on the hook until the valve outlets are welded to each other.

The purpose of the invention is to simplify the assembly of precast concrete columns.

This goal is achieved by the fact that in the butt joint of precast reinforced concrete columns, coupled with face-up surfaces, including corner and intermediate reinforcement outlets, located in the hollow grooves, the corner outlets of the reinforcement are connected by tensioning devices.

In addition, the clamping device is made in the form of sleeve-type couplings.

FIG. 1 shows a butt joint of precast reinforced concrete columns, general view; in fig. 2 - section A-A of FIG. one; in fig. 3 shows the node I in FIG. one; in fig. 4 - section bb FIG. 3; in fig. 5 shows a section bb of FIG. 3 in FIG. 6 shows a section of the perspective view, prepared for concreting.

The butt joint of precast reinforced concrete columns 1 and 2 includes releases of reinforcement 3 interconnected by means of bath seam welding 4, and mating welded surfaces 5.

The ends of the corner fittings 6 have heads 7, on which they are loosely attached to clamping devices. Some of them are tube cups 8 with an external thread 9 and a hexagonal rim 10, and others are tensioning sleeves 11 with a hexagonal outer surface 12 and an internal thread 13. At the locations of the outlets of the armature 3, grooves 14 in the shape of a dovetail tail are made, facing with the expanded side 15 into the body of the joined columns 1 and 2. The shape of the grooves in cross section can be made in the form of a circle 16 with a segment notch 17 coinciding with the outer surface of the joined columns. The grooves 14 and 16 are monolithic with solution 18 on expanding cement.

. The technological peculiarity of the manufacture of precast concrete columns 1 and 2 with mating flanged surfaces 5 at the junction is that columns 1 and 2 are made in one common formwork. To do this, side shields of formwork with a length equal to the total length of columns 1 and 2 are placed on the strictly horizontal surface of the pallet and the boards are fixed in a vertical position. In the place of the future joint, a separating diaphragm 19 made of a thin metal sheet with a thickness of 0.6-1.5 mm is installed (see Fig. 6) and fixed to the side shields of the formwork. Then, reinforcement 3 is placed on the left and right of diaphragm 19, and the rods 3 must be coaxial with each other and fit close to the diaphragm 19. To form the recesses in the concrete body that are necessary for access to the reinforcement or mounting releases, wooden inserts are put on the ends of the rods 6 20 which have longitudinal grooves 21.

FIG. Figure 6 shows the stacking unit for the rods 3 with the stoppers 8 and the tightening sleeves 11 in the wooden inserts 20 with the recesses 22 already attached to their ends with recesses 22 for these purposes. In order to protect the caps 8 and the shrinkable sleeves 11 from hitting concrete when vibrating, the grooves 22 in the wood liners 20 are filled with clay or gypsum.

Wood liners are installed in the same way for lower reinforcing bars in the joint.

The following steps for the manufacture of columns 1 and 2 are: concreting, heat treatment, marking of columns and stripping. During the demolding, the side panels are removed and the finished columns 1, 2 are separated from each other, with the metal diaphragms 19 and the wooden inserts 20 being released from the joints for subsequent use.

In this way, joints are obtained in which the concrete surfaces of the ends of the joined columns 1 and 2 have adjoining welded surfaces. A feature of the manufacture of columns with the proposed joint is that if one of the columns has a slight convexity on the surface of the concrete of the joint (the diaphragm 19 may be slightly bent during concreting), then the other column adjacent to the first one is concave. connection of columns G, 2 on installation.

The installation of the columns is as follows.

The upper column 1 is installed on the lower column 2 and, first of all, connects the fittings 6 with the help of glasses-stoppers 8 and tightening couplings 11, screwing them into each other with a wrench. After connecting the four pairs of outlets of the reinforcement 6 to each other, the hook of the lifting mechanism is released and the column 1 can stand without support. Then, the outlets of the reinforcement 3 are connected to each other using bath seam welding 4. When welding the outlets of the reinforcement 3 between them, they are heated, and then during cooling they are shortened, as a result of which the joined concrete surfaces of the columns receive additional compression. The same thing happens when the reinforcement 6 releases are connected with each other by means of glass plugs 8 and tightening sleeves 11. To protect the reinforcement releases 3, 6 from corrosion, the grooves 14 and 16 are filled with solution 18 on the expanding cement. When hardened, the solution 18 fills the grooves 14, 16 tightly.

Using the invention in practice allows to simplify the installation of columns.

Claims (3)

1. The butt joint of precast reinforced concrete columns mated with hinged surfaces, including corner and intermediate reinforcement outlets, located in hollowed grooves, characterized in that, in order to simplify installation, the angle outlets of the reinforcement are connected by tensioning devices. 2. Butt joint according to Claim. 1, characterized in that the clamping device is made in the form of sleeve-type sleeves. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 108012, cl. E 04 C 3/34, 1956. 2. USSR author's certificate number 331162, cl. E 04 C 3/34, 1970. 3. Sverdlov P. 1A. On the joints of precast concrete structures of thermal electric space. “Industrial construction № 6, 1964. b L J.