RU74652U1 - MULTI-EMPTY REINFORCED CONCRETE PLATE - Google Patents

Abstract

1. Multi-hollow reinforced concrete slab designed for operation in seismic conditions, obtained by continuous formless vibrocompression with oval voids and prestressed reinforcement in the form of parallel longitudinal rods and elements of transverse reinforcement, equipped with dowels on the side surfaces, characterized in that it has reinforcing outlets parallel to longitudinal rods in the lower part of the plate from the side of its end face and is equipped with two pairs of additional longitudinal reinforcing bars, in the bridges between the voids symmetrically relative to the longitudinal axis of the plate, the rods of each pair are parallel to each other in the upper and lower parts of the jumper, each pair of additional longitudinal rods formed by passing a single rod through the jumper between the voids, forming a stitch on the jumper, between the additional longitudinal reinforcing rods each pair is placed along the entire length of the plate a wave-like wire conjugated at separate points with the lower and upper additional longitudinal rods E by wire clamps or spot welding to hold it in the stretched state, the undulated wire is obtained by stretching a wire pruzhiny.2 compressed. The multi-hollow reinforced concrete slab according to claim 1, characterized in that the height of the ribs formed by the voids is more than 2-3 times their average width, the reduced thickness of all the ribs should be at least 0.25 of their reduced width, but not more than 1.5 times, the averaged step of the wave-like wire is chosen equal to not more than half the design height of the plate, and the reinforcement

Description

The utility model relates to the field of construction and can be used for the manufacture of precast-monolithic ceilings in the construction of residential, public and industrial buildings in areas with increased seismic activity using vibrocompression methods.

Known plates for earthquake-resistant structures that use prestressed longitudinally sliding reinforcing bars and tensile bridges (1). However, the known designs have increased material consumption and manufacturing complexity.

More advanced multi-hollow slabs with oval voids are known, which can be used in earthquake-resistant building structures (2). However, complex reinforcement, as well as imperfect technology for the manufacture of plates, leads to a higher cost of production due to high material consumption. This technical solution is the closest to the declared one.

The technical task of this technical solution is to create a plate designed to work in earthquake-resistant building structures, which is easy to manufacture and has low material consumption.

The above problem is solved due to the design features of the plate, its reinforcement in combination with the features of the technology of its manufacture.

The essence of the claimed technical solution boils down to the fact that in a multi-hollow reinforced concrete slab designed to work in seismic conditions, obtained by continuous formless vibropressing with oval voids narrowed up and prestressed in the form of parallel longitudinal rods and transverse reinforcement elements and provided with dowels on the side surfaces the above plate has reinforcing outlets in cross section at the bottom of the plate from the side of its end and is equipped with two pairs of additional longitudinal reinforcing bars placed in the bridges between the voids symmetrically with respect to the longitudinal axis of the plate. The rods of each pair are placed parallel to each other in the upper and lower parts of the jumper. Each pair of additional longitudinal rods is formed by passing a single rod through the jumper between voids, forming a stitch on the jumper, between the additional longitudinal reinforcing rods of each pair, a wave-shaped wire is placed along the entire length of the plate, conjugated at separate points with the lower and upper additional longitudinal rods by wire clamps or point welding to hold it in a stretched state along the length of the plate, and a wave-like wire obtained by stretching previously compressed wire spring.

In a multi-hollow reinforced concrete slab, the height of the ribs formed by the voids can be selected more than their

the averaged width is not more than 2-3 times, while the reduced thickness of all the ribs should be at least 0.25 of their reduced width, but not more than 1.5 times, the averaged step of the wave-like wire is chosen to be equal to not more than half of the design plate height , the reinforcing outlets of the longitudinal reinforcing bars are chosen equal to at least half the height of the slab, and concrete plugs are installed at the ends of the voids at a distance from the ends of not less than the width of the void and a thickness of at least half the width of the void.

The drawings show an example of a plate according to the present technical solution.

Figure 1 - General view

Figure 2 is a fragment of the pairing of the longitudinal additional rods with a wave-like wire.

Multi-hollow plate 1 obtained by continuous formless continuous vibration. Its voids 2 in cross section have an oval shape narrowed in the upper part. The plate in the lower part has outgrowths of longitudinal reinforcement 3 approximately 10 cm long. There are dowels on the sides of the plate 4. In the jumpers 5, pairs of additional longitudinal rods 6 are placed between the voids 6. The pairs of additional longitudinal rods 6 are parallel to each other in the plate body and are symmetrical with respect to longitudinal axis 7 of the plate. Each pair of additional longitudinal rods of the plate is formed by passing a single rod through the jumper 3 between the voids 2. A stitch 8 of the transverse reinforcement is formed on the surface of the jumper 3. Between the rods 6 of each pair of additional longitudinal rods is located

wavy wire 9 along the entire length of the plate. A wave-like wire 9 is obtained by stretching a previously compressed spring, which provides prestress to this reinforcement element. In some parts along the length, the wave-like wire 9 is fastened to additional longitudinal rods 6 by means of wire clamps 10 or spot welding (not shown). For the convenience of concreting, because of the voids narrowed up, the ribs expand upward, while the height of the ribs H is greater than their average width B no more than 2–3 times depending on the height of the slab. To ensure the strength of inclined sections, the reduced thickness of all edges of the plate should be more than average, but not more than one and a half times. It is proposed that at least half of the height of the plate, about 10 cm, is exited from the ends of the plates. The average step of the wave-like wire is not more than half the design height of the plate. For the formation of a rigid and durable horizontal carrier disk of a prefabricated monolithic overlap that accepts vertical shear and horizontal shear forces on the lateral faces of the plates, it is calculated that continuous longitudinal trapezoidal grooves and discontinuous recesses of at least 10 mm in depth are formed, which, after monolithic inter-plate joints with non-shrink fiber-reinforced concrete, form reliable veneers connections that do not require additional reinforcement with steel reinforcement can be at the ends of voids concrete plugs are installed at a distance from the ends of not less than the width of the void and a thickness of not less than half the width of the void.

Thus, at the minimum cost of reinforcement, a sufficient fracture strength of the plate is achieved at

multidirectional vibration loads, since the dowels allow the plate to move relative to the adjacent plate in the overlap, and the wave-like springs placed in the proposed way prevent the plate from breaking due to their sliding with respect to the additional longitudinal rods, as well as due to the transverse tightening due to the execution of each pair of additional longitudinal rods from single element of the shingles.

The implementation of the slab according to this technical solution allows you to reduce the cost of construction in earthquake-prone areas, increases the reliability of buildings with minimal material consumption.

INFORMATION SOURCES:

1. FROM. RF №1807195 Е04С 3/00 1983

2. PM of the Russian Federation No. 2087640 Е04С 2/06 1997

Claims (2)

1. Multi-hollow reinforced concrete slab designed for operation in seismic conditions, obtained by continuous formless vibrocompression with oval voids and prestressed reinforcement in the form of parallel longitudinal rods and elements of transverse reinforcement, equipped with dowels on the side surfaces, characterized in that it has reinforcing outlets parallel to longitudinal rods in the lower part of the plate from the side of its end face and is equipped with two pairs of additional longitudinal reinforcing bars, in the bridges between the voids symmetrically relative to the longitudinal axis of the plate, the rods of each pair are parallel to each other in the upper and lower parts of the jumper, each pair of additional longitudinal rods formed by passing a single rod through the jumper between the voids, forming a stitch on the jumper, between the additional longitudinal reinforcing rods each pair is placed along the entire length of the plate a wave-like wire conjugated at separate points with the lower and upper additional longitudinal rods E by wire clamps or spot welding to hold it in the stretched state, the undulated wire is obtained by stretching the wire spring compressed. 2. Multi-hollow reinforced concrete slab according to claim 1, characterized in that the height of the ribs formed by the voids is more than 2-3 times their average width, the reduced thickness of all the ribs should be at least 0.25 of their reduced width, but not more than 1.5 times, the averaged pitch of the wave-like wire is chosen equal to not more than half the design height of the plate, and the reinforcing outlets of the longitudinal reinforcing bars are selected to be at least half the height of the plate, and concrete plugs are installed at the ends of the voids at a distance from the ends of not less than the width mouth and a thickness of at least half the width of the void.