RU2383692C1 - Butt joint of monolithic slab with column - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention is related to the field of construction, in particular to butt joint of monolithic slab with column. Butt joint of monolithic slab with column 1 comprises column 1 and ceiling slab 2. Column 1 and ceiling slab 2 comprises reinforcing cages 3 and 4 accordingly. Plates 5 are arranged on reinforcing cage of ceiling slab 2 in direction from column 1 to ceiling slab 2. Plates 5 are arranged in the form of bent section bars and are equipped with stiffening elements 6. Stiffening elements 6 are installed along each plate 5 as pairwise on both sides at least along upper and lower ends of plate 5.

EFFECT: reduced metal intensity of plates by reduction of their weight, simplified design and reduction of the whole unit weight without deterioration of its reliability and bearing capacity.

2 cl, 6 dwg

Description

The invention relates to the field of construction, namely to the construction of prefabricated reinforced concrete floors, and can be used in structures of supporting structures of beam-free floors.

Known butt connection of the capitals of bezel-free reinforced concrete floors with the column according to the author's certificate of the USSR No. 876907, class. ЕВВ 5/43, 1981. It contains the central part of the slab with an opening widening downwards and the reinforcing outlets of the column and slab; a reinforcing cage protruding from under the plane of the capital in the form of a truncated pyramid or a truncated cone and attached to the outlets is placed in the hole for the passage of the column reinforcement of the column and capitals, and the column in the joint zone is profiled with alternating grooves and ridges, and the joint cavity is monolithic.

The disadvantages of this butt joint are the high labor costs and material consumption of the node connecting the columns with the slab.

Known for the butt connection of beam-free reinforced concrete floors with a column according to the patent of the Russian Federation No. 2194825, class. EBB 5/43, 2002, adopted by the applicant for the prototype. It contains a column and a slab, reinforcing cages of a column and a slab, opposite each column face is symmetrical with respect to the axis of the column, plates are fixed on the reinforcing cage of the lower and upper grid of the slab in the direction from the column to the slab, the plates are made at least 2h + 2a, where h is the thickness of the floor slab, and is the thickness of the protective layer of concrete of the column, and installed on the edge, and one end of each plate is made in a rectangular shape and is installed beyond the edge of the column at a distance not less than 2a, and the other has a bevel at an angle of 45 degrees, located perpendicular to the side surface of the prism of the plate forcing.

However, such a connection of the column with the slab requires a significant consumption of metal, which is directly related to the increase in the weight of the structure.

An object of the invention is to reduce the metal consumption of the plates by reducing their weight and simplifying the design, as well as reducing the weight of the entire assembly as a whole without reducing its reliability and bearing capacity.

The problem is solved in that in the proposed technical solution, the plates are made in the form of bent profiles and are equipped with stiffeners, and the stiffeners are installed along each plate in pairs from two sides, at least at the upper and lower ends of the plate.

In addition, the bent profile of the plates is made in the form of either a sinusoid, or a rectangle, or a trapezoid, and the stiffeners are made of either reinforcement, or a strip, or a corner, or a channel and are fastened to the plate by welding or fasteners.

Figure 1 shows the connection of the column with the slab using plates in the form of bent profiles (the upper and lower grids of the reinforcing cage of the slab are not shown conventionally);

figure 2 is a section aa in figure 1;

figure 3 - plate, equipped with stiffeners made of reinforcement and connected to it by welding;

figure 4 - types of bent profiles of the plate;

figure 5 - examples of stiffeners;

figure 6 - fastening of the stiffeners to the plate by means of either welding or fasteners.

A butt joint of a bezel-free reinforced concrete floor with a column includes a column 1 and a floor slab 2, inside of which reinforcing cages are placed, respectively: 3 - the reinforcing cage of the column and 4 - the reinforcing cage of the floor slab. Opposite each face of the column 1 symmetrically with respect to the axes of the column and the floor slab 2, plates 5 are rigidly fixed in the direction from the column 1 to the floor slab 2. All plates 5, at least two opposite each face of the column, are mounted on the rib. Moreover, each plate 5 is placed between the upper and lower grids of the reinforcing cage 4 of the floor slab and is rigidly connected to them. And also each plate 5 is made in the form of a bent profile and is equipped with stiffening elements 6, which are installed along each plate 5 in pairs from two sides, at least at the upper and lower ends. This design of the plate is much thinner and requires less metal, is much lighter than a flat one and surpasses the analogue in bearing capacity. When performing a very critical building structure, requiring a more reinforced floor slab with increased bearing capacity, additional stiffening elements 6 can be placed along the height of the plate 5 between its upper and lower ends.

The bent profile of the plate can be represented by several types of curves, for example: in the form of a sinusoid, rectangle, trapezoid, triangle and other similar shapes. And the stiffening elements 6 can be made, for example: from reinforcement, bar, strip, angle or channel and the like. The fastening of the stiffening elements 6 with the plate 5 is carried out by, for example: resistance welding, knitting wire, through clamps or other fastening elements 7.

Installation of the butt joint is as follows.

The bottom grid of the reinforcing cage 4 of the floor slab 2 is laid on the formwork brought under the overlap (not shown conditionally), while the reinforcing cage 3 of the column 1 is already brought out above the formwork. Then the prepared plate 5 is installed on the rib and attached to the bottom mesh of the reinforcing cage 4 of the floor slab 2.

Preliminary preparation of the plates is as follows. To a plate made of the calculated length, thickness and with a selected profile, stiffeners 6 are attached in pairs along the upper and lower ends, also calculated from the proposed series, depending on the required bearing capacity and the presence of certain stiffeners 6. At the same time, The assembly of plates 5 with stiffeners 6 can be combined with their installation on the reinforcing cage 4 of the floor slab 2 directly at the construction site.

After that, the upper mesh of the reinforcing cage 4 of the floor slab 2 is installed and also fastened to the plates 5. The joint is ready for filling with concrete.

Plates with a bent profile are more resistant to long-term static load. In addition to the benefits derived from production technology, a sinusoidal rib has an advantage over the direct one due to the elimination of local deformation inherent to flat plates. Thanks to the profiled plate, the structure effectively dampens bending loads. Under conditions of static load, the plate is calculated according to a scheme in which bending moments and normal forces are transmitted only through the shelves: after connecting with the stiffeners, the plate takes the form of an I-beam, in which the stiffeners serve as beam shelves, and the transverse forces are distributed only through the diagonals and vertically formed beams - in this case, through a corrugated wall.

The use of the proposed technical solution made it possible without loss of reliability and load-bearing ability to create a butt joint of a monolithic overlap with a column, which allowed to reduce the metal consumption of the plates by an average of 40%, reduce the weight of building structures, save the metal used due to the sufficient load-bearing capacity of the plates in the form of bent profiles equipped with stiffeners and representing beams. And also the use of the proposed technical solution allows to reduce the cost of work and increase their productivity.

Claims (2)

1. A butt joint of a monolithic overlap with a column containing a column and a floor slab, reinforcing cages of the column and floor slabs installed on the reinforcing cage of the floor slab in the direction from the column to the floor slab, characterized in that the plates are made in the form of bent profiles and equipped with elements stiffness, and the stiffening elements are installed along each plate in pairs from two sides, at least at the upper and lower ends of the plate. 2. The butt joint according to claim 1, characterized in that the bent profile of the plates is made in the form of either a sinusoid, or a rectangle, or a trapezoid, and the stiffeners are made of either reinforcement, or a strip, or a corner, or a channel and fastened to the plate by welding or fasteners.

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