SU881243A1 - Flat prestressed and reinforced construction element and method of its manufacture - Google Patents

Description

one

The invention relates to road construction, industrial and civil construction, and can be used in the construction of road pavements and in industrial and civil structures.

Reinforced concrete structures with longitudinal-transverse prestressing of reinforcement are known 1

The disadvantages of such structures are the large laboriousness of their manufacture, the rigidity of the tooling and the insufficient bearing capacity of the element.

The closest technical solution to the invention is a flat, load-reinforced building element with a reinforcing cage in the form of a grid with cells of rhombuses or squares, the sides of which are angled to the outer face of the building element; made by a method that includes the installation of a reinforcement cage, the laying of concrete and the preliminary tension of the reinforcement along the axis of the reinforcement bar 2.

The disadvantage of such structures is the low stiffness of the element, as well as

the complexity of its manufacture due to the tension of the reinforcement on the hardened concrete.

The purpose of the invention is to increase the rigidity and crack resistance in the longitudinal and transverse directions and simplify the manufacturing technology.

This goal is achieved by the fact that in a flat, load-reinforced construction element with a reinforcement cage in the form of a grid with cells of rhombuses or squares, the sides of which are angled to the outer face of the construction element, rhombuses or squares of the reinforcement mesh are connected at the vertices by interlacing reinforcing bars according to the type of an armor mesh or by means of ring grippers; besides, the frames are installed in parallel planes with their displacement relative to each other, while at the top of rhombuses or squares are located additionally the longitudinal rods.

In the method of manufacturing a flat tension-reinforced building element, including the installation of a reinforcement cage in the form of a grid with cells of rhombuses or squares, the sides of which are angled to the outer face of the stronghold element, the placement of concrete and the pre-tensioning of reinforcement, the preliminary tension of reinforcement t before laying concrete outside the outer tops of rhombuses or squares located along the longitudinal edges of the element in the direction of their diagonals. In addition, the outer vertices of rhombuses or squares located along one of the longitudinal edges can be fixed.

FIG. 1 shows a frame of reinforcing bars interlaced on the principle of an armor-clad grid; in fig. 2 - frame made of individual diamond-shaped elements connected by additional fixing parts; in fig. 3 - diamond-shaped frame with longitudinal rods; in fig. 4 - reinforced concrete slab with frames arranged in parallel planes; in fig. 5 way of tensioning the diamond-shaped frame across the width of the reinforced concrete slab on both sides with fastening the ends and tops of the end parts of the frame; in fig. 6 - one-sided way of tensioning the diamond-shaped frame from the side of the long face, with fixing the end parts of the frame on the other sides.

The element in the form of a slab consists of a concrete body 1, a skeleton 2 containing prestressed reinforcement interlaced according to the type of an armor mesh 3 or connected at the vertices with the help of grippers 4 and additional longitudinal rods 5.

The cores, prior to their placement in the slab, are given a curved shape so that their intersection creates diamond-shaped or square shapes, for example, for a construction where small cross-section reinforcement is used, according to the type of armor mesh. Depending on the ratio of the efforts of compressing the element in one direction or another, the frames of individual, prefabricated rhombuses or squares are laid in such a way that their vertices at the intersection points are fixed in the general shape stop or with each other. The armature can be made from a single rod by bending in the conductors or individual diamonds with the connection of their tops, for example, rings.

To ensure increased rigidity of the slab structure, additional longitudinal rods may be installed near the tops of rhombuses or squares.

For example, in slabs with a large thickness, frames of rhombuses or squares may be arranged in parallel planes with mixing relative to each other in a horizontal plane.

Rhombic or square frame sections are tensioned diagonally by stretching them across or along the element. Such an expansion, due to the principle of levers, allows for less effort to be applied while

degrees of tension in comparison with simple linear tension of reinforcement along the axis, frame.

For example, for slabs of small width, the tension of the frame sections with rigidly fixed mating faces is produced in a diagonal direction for their tops at opposite faces.

The use of frames of the proposed type of reinforcement allows to significantly simplify the manufacturing technology and equipment, increase the spatial rigidity of the structure.

Claims (5)

1. Flat stress-reinforced building element with reinforcing cage in the form of a grid with cells of rhombus or squares, the sides of which are angled to the outer face of the building element, characterized in that in order to increase rigidity and crack resistance in the longitudinal and transverse directions, rhombuses or squares of the reinforcing mesh are connected at the vertices by interlacing reinforcing bars according to the type of an armor-clad mesh - or by means of ring grippers. 2. An element according to claim 1. characterized in that additional longitudinal rods are installed at the vertices of rhombuses or squares. 3- The element according to claim 1, characterized in that the frames are installed in parallel planes with displacement relative to each other. 4. A method of manufacturing a flat tension-reinforced building element, including installing a reinforcement cage in the form of a grid with cells of rhombus or squares, the sides of which are angled to the outer face of the building element, laying concrete and pre-tensioning the reinforcement, that, in order to simplify the manufacturing technology, the prestressing of the reinforcement is carried out prior to laying the concrete over the outer tops of the rhombus 5 squares located at the longitudinal edges of the element in the direction of their diagonals. 5. A method according to claim 4, characterized in that the outer vertices of rhombuses or squares located along one of the longitudinal  edges fixed. . Information sources; taken into account in the examination 1.Gervik B. Pre-stressed reinforced concrete structures in construction. M., stroiizdat, 1978, p. 304-307. 2. US patent number 3513609, class. 52-230, publ. 1970.