RU68029U1 - MULTI-EMPTY REINFORCED CONCRETE PLATE - Google Patents

Abstract

Offer applies to building parts and construction. in more detail to multi-hollow reinforced concrete slabs obtained by vibropressing. The objective of this utility model is to create a plate with reduced material consumption, in particular metal consumption while maintaining fire resistance, the manufacture of which can be easily modified without complicating the technology. The problem is solved by increasing the distance to the lower row of wires, as well as the proposed reinforcement scheme. The rods are grouped in beams with a certain distance between them, the beams are arranged in a row along the width of the plate, so that at least one rod or lower rods of the beams are installed at a distance from the edge of the plate no more than 20 mm, the design is symmetrical with respect to the longitudinal axis plates, the total number of wires is determined both in the lower and upper zones. 1 s.p.

Description

The invention relates to the field of construction and can be used in the construction of residential, public and industrial buildings with load-bearing walls made of bricks or large blocks, as well as in frame and prefabricated monolithic buildings erected under normal construction conditions.

A multi-hollow building panel is known in which reinforcement is carried out using volumetric turns of wire with a diameter of class BpII from 3 to 10 mm (L.1). However, in the known technical solution, the problem of reducing the metal consumption is not solved.

A multi-hollow building slab is known, in which the reinforcement is located at the edges of the slab symmetrically with respect to the transverse axis (L.2.). The known solution also does not solve the problem of saving metal, in addition, due to the presence of transverse brackets, the method of manufacturing such a plate is complicated.

Closest to the claimed technical solution is the stove described in L.3. The reinforcement in the known technical solution is installed in the edges of a multi-hollow panel, its diameter is 6-10 mm, the reinforcement is prestressed, the panel is made by vibrocompression, while the reinforcement rods are installed along the lower edge of the panel at a distance of 40-50 mm from the edge and form a three-dimensional frame.

However, the placement of the reinforcement in relation to the lower edge of the plate, as well as its execution in the form of a frame, does not allow us to consider this option for the panel to be quite successful, since it does not provide the required fire resistance of the plates, and is also quite difficult from a technological point of view.

The technical task of the present invention is the creation of multi-hollow reinforced concrete slabs with reduced material consumption, in particular metal consumption, while fire-resistant, the manufacture of which can be easily modified without complicating the technology. The problem is solved by increasing the distance to the lower row of wires, as well as the proposed reinforcement scheme.

The essence of the claimed technical solution lies in the fact that in a multi-hollow reinforced concrete slab made of heavy concrete, obtained by vibrocompression and designed for evenly distributed load from 300 to 1600 kgf / m2, which is reinforced with prestressed high-strength wire with a diameter of class BpII from 3 to 10 mm having a lower row of reinforcement made of wire of the same diameter in the form of parallel rods mounted in parallel in the longitudinal direction, with ribs located with the same in steps, at least one lower reinforcement bar or rods are installed at a distance of 20 mm from the lower edge of the plate, and the upper one at the level of the end of the rib experiencing bending stress, the rods are grouped in bundles of 3-10 wires with a distance between them from 10 to 12 mm, while the bundles of wires are installed in a row in width

slabs, and each bundle in the projection onto the end face of the slab forms a figure symmetrical about the axis of the ribs, while the reinforcement beams are installed symmetrically about the longitudinal axis of the slab; the diameter of the wire can be chosen equal to 5 mm, in addition, reinforcement of the same diameter in the amount of not more than 4 wires can be installed in the upper zone of the plate, and the total number of wires in the bottom row is selected from 7 to 45 pieces depending on the load.

Multi-hollow reinforced concrete floor slabs are designed for loads of 300, 450, 600, 800, 1000, 1250, 1600 kgf / m2.

The drawings show examples of reinforced plates according to the present invention.

Figure 1 presents a variant with reinforcement of 4 beams in the bottom row, where each bundle consists of five rods, and 4 rods on the top.

Figure 2 is a variant of 5 beams on the lower edge of the plate and 4 rods on the upper;

Figure 3 is a variant of 6 beams from the bottom and 4 rods from above;

Figure 4 is a variant of 7 beams from the bottom and 4 rods from above;

Figure 5 is a variant of 8 beams from the bottom 4 rods from above;

6 is a variant of 9 beams from the bottom and 4 rods from above;

7 is a variant of four rods in the rib.

Examples are given for slabs made of heavy concrete B30 for compressive strength, with oval voids forming ribs, the initial prestressing value of the lower reinforcement is 12000 kgf / cm2, the top - 6000 kgf / cm2, with the dimensions of the plate: height 220 mm, width - 1200 mm, length - from 2.4 to 9 m, wire diameter 5 mm

BPII. Wire of class BpII is high-strength with a periodic profile (corrugated), see A.S. Toropov Reinforcing works, Moscow, Higher school, 1976, p.199. In the upper part, 4 wires are usually used, however, plates can be made without upper reinforcement. Plates without upper reinforcement are designed primarily for frame buildings, in low-rise construction with a hinged support system. By increasing the distance to the lower row of wires forming the bundles and placing part of the wires in the lower part of the rib - lowering this lower row to a distance of 20 mm from the lower edge of the plate increases the fire resistance of the plates. In order to maintain the reliability of plate bending, as well as to prevent cracking and to allow modification of plates for various loads, wire rods are bundled, wire bundles are installed symmetrically about the longitudinal axis, and each bundle in the projection onto the end face forms a symmetrical figure relative to the axis of the ribs as shown in the figures. From these considerations, the optimal distances between the wires were found. Beam patterns can be combined.

It has been experimentally established that the proposal to reinforce multi-hollow reinforced concrete slabs according to the present invention can significantly reduce the metal consumption of the structure.

The boards proposed according to the present invention have an estimated fire resistance limit of REJ45, which allows their use in buildings of the second degree of fire resistance without any additional measures.

Information sources:

1. PMRF No. 2081266 E04C 2/02 1997

2. PMRF No. 2109892 E04C 2/06 1998

3. PAT. RF №2199637 Е04С 2/06 2001

Claims (2)

1. Multi-hollow reinforced concrete slab of heavy concrete, obtained by vibropressing, designed for uniformly distributed load from 300 to 1600 kgf / m ² , reinforced with prestressed high-strength BpII wire with a diameter of 3 to 10 mm, with at least one lower row wire reinforcement in the form of parallel rods installed along the length of the plate; the plate has ribs, and the above ribs are arranged with the same pitch, characterized in that at least one rod or lower rods are installed at a distance of not more than 20 mm from the bottom of the plate, the rods are grouped in bundles of 3-10 wires with a distance between wires of 10 up to 12 mm, wire bundles are arranged in a row along the width of the plate, each bundle in the projection onto the end face of the plate forms a figure symmetrical about the axis of the ribs, wire bundles are installed symmetrically with respect to the longitudinal axis of the plate, with the total number of wires 7 to 45 pieces are selected. 2. Multi-hollow reinforced concrete slab according to claim 1, characterized in that the wire diameter is 5 mm, additionally in the upper zone there is a reinforcement in the amount of not more than 4 wires.