RU2194127C2 - Reinforced-concrete frame of building or structure - Google Patents

Abstract

FIELD: construction engineering. SUBSTANCE: reinforced-concrete frame of building or structure includes columns with crosswise located holes in level of ceilings and ceiling disc consisting of prefabricated plates, edge and cantilevered members, and prestressed reinforcement running through column holes. Ceiling disc consists of monolithic mutually intersecting reinforced-concrete belts running along longitudinal and transverse axes of column nets. Laid inside belts are prestressed reinforcement with transmission of tension forces to reusable mounting braces installed between adjacent columns. Prefabricating plates are laid into cells formed by monolithic belts. EFFECT: simplified mounting of building-structure frame. 3 cl, 6 dwg

Description

 The invention relates to the field of construction and can be used in the construction of residential buildings and structures with precast-monolithic reinforced concrete frame.

 Reinforced concrete buildings are known, the frame of which includes columns with cross-shaped openings at the level of the floors and floor slabs, combined with columns of tensioned reinforcement at the construction site, passing along the axis of the columns in the joints between the floor slabs (SFRY Patent 25452, US Pat. No. 4,366.655; B. G. Kornilov, Frame-panel buildings of a new type. - Housing, 1986, 10).

 There is also known a method of prestressing the floor, consisting of columns and a floor slab resting on them, the combination of which with the columns is performed by reinforcement which is tensioned during the installation process, the essence of which is that mounting (inventory) spacers are installed between adjacent columns, to which the efforts of the voltage are transmitted valves (application 98106054/03 on the grant of a patent of the Russian Federation for the invention of April 9, 1998).

The prototype of the invention is the patent of SFRY 25452, published March 31, 1966. The disadvantages of this invention are:
- the complexity of the geometry of prefabricated floor slabs, edge beams and cantilever slabs having cutouts in the corners adjacent to the columns. The reinforcement of these corner zones, where great efforts are concentrated in the process of prestressing, is notable for its complexity and busyness;
- the erection of the structure is carried out by tensioning the reinforcement in the way "on concrete", which leads to technological interruptions necessary for hardening concrete in the joints between the slab and the column, as well as mortar in the openings of the columns, which is especially unfavorable in winter conditions of construction.

 The aim of the invention is to simplify the design of prefabricated floor slabs and their reinforcement, as well as simplifying the design and reinforcing of the edge and cantilever zones of the floor slab, as well as eliminating technological interruptions during the installation of the frame.

 This is achieved by the fact that the overlapping disk is made of monolithic, including edge and cantilever sections, mutually intersecting reinforced concrete belts located along the longitudinal and transverse axes of the column grid, tensioning reinforcement is laid inside the section of the belts with the transfer of tension forces to the inventory mounting brackets installed between adjacent columns , as well as, possibly, the usual reinforcement of the overlapping disk, while the prefabricated plates are stacked in cells formed by monolithic belts and connect them to the exhaust belts ami fittings.

The listed design decisions:
- simplify the geometry and reinforcement of prefabricated floor slabs, in which there are no angular cuts and zones of concentration of effort. Therefore, conventional standard multi-hollow decks that are widely used in mass construction can be applied. Reinforcing monolithic edge and cantilevered sections of the floor is much simpler than reinforcing prefabricated edge beams and cantilever plates;
- technological breaks for hardening of concrete are excluded, since the applied method of tensioning the fittings “on the stops” allows the installation of structures of the next floor of the building without waiting for the hardening of concrete monolithic belts of the previous floor;
- the transfer of prestressing forces from the mounting brackets to the overlap disk is carried out over a substantially larger area of concrete: instead of the concentration of forces in the corner zones, they are evenly distributed over the entire width of the column and transferred to a monolithic reinforced concrete belt.

 In addition, in the proposed frame design, it is possible to use a key connection of the floor to the columns, which allows significantly (up to 50%) reduction in the number of prestressed reinforcement, the structural solution allows significantly lowering the concrete strength class for prefabricated floor slabs.

 In FIG. 1 shows a fragment of a plan of a frame building; in FIG. 2 shows a section through 1-1 in FIG. 1; in FIG. 3 shows section 2-2 in FIG. 1; in FIG. 4 shows the assembly “A” in FIG. 1; in FIG. 5 shows a section through 3-3 in FIG. 4; in FIG. 6 shows a section through 1-1 in FIG. 1 for the moment of installation of inventory struts between the columns.

 The reinforced concrete frame (Fig. 1 and 2) consists of columns 1 and a floor slab, consisting of monolithic mutually intersecting belts 2 located along the longitudinal and transverse axes of the grid of columns. The width of the belts "a" (Fig. 2) can be taken larger than the size of the faces of the column "b", which allows, if necessary, to continuously reinforce the belts with conventional reinforcement 3 (in addition to the tensioned one) (Fig. 3) for the entire length and width of the building section . Inside the belts 2 there is a prestressing reinforcement 4 extending along the axes of the grid of the columns, through openings in the columns that are crosswise located at the level of overlapping (Figs. 1 and 3).

 Prefabricated plates 5 fill the cells of the overlap disk formed by monolithic belts (Fig. 1 and 2). At the seams between the prefabricated plates and, possibly, in the plates, reinforcing cages or outlets 6 are placed for their connection with monolithic belts.

 Since the width of the monolithic belts may be greater than the width of the faces of the columns, it is possible to install bent reinforcement 7 (Figs. 4 and 5) in the column area to absorb shearing forces from the action of transverse forces.

 In FIG. 5 shows the device on the column along its perimeter within the overlap thickness of the key connection 8 for combining the column with the overlap in addition to connecting them using prestressing reinforcement.

 The construction of the frame begins with the installation of columns 1, between which install inventory mounting spacers 9 (Fig. 6). Spacers are installed between the columns without gaps below the level of the future disk overlap (Fig. 6, the disk is shown in dashed lines). Prefabricated floor slabs are mounted on temporary mounting supports 10 (Fig. 2), and formwork of reinforced concrete belts, edge and cantilever sections of the floor disk are also installed. After this, the prestressing reinforcement is laid along the longitudinal and transverse axes of the building and conventional reinforcement in monolithic belts and cantilevered sections of the ceiling. After installing the fittings, the tensioned fittings are tensioned to the design forces with the transfer of prestressing forces to the mounting struts, and then the monolithic belt is concreted and the solution is filled with holes in the columns through which the tensioned fittings pass.

 After these operations, you can proceed to the installation of the structures of the overlying floor. Prestressing forces are transferred from the mounting spacers to the concrete of the floor drive with a gap of 1-2 floors from the installation work on the building frame, when the monolithic concrete and mortar in the openings of the columns gain at least 70% of the design strength.

Claims (3)

 1. The reinforced concrete frame of a building or structure, including columns with crosswise openings at the level of the floors, a floor disk consisting of prefabricated plates, edge and cantilever sections and prestressed reinforcement passing through the holes in the columns, characterized in that the floor disk is made of monolithic including boundary and cantilever sections, mutually intersecting reinforced concrete belts located along the longitudinal and transverse axes of the grid of columns, strain is placed inside the section of the belts reinforcement and pull it with the transfer of tension to the inventory mounting spacers installed between adjacent columns, as well as, possibly, conventional reinforcement, while prefabricated plates are laid in cells formed by monolithic belts.  2. The reinforced concrete frame according to claim 1, characterized in that on the columns within the thickness of the overlap disk, the key connections of the overlap to the columns are made.  3. The reinforced concrete frame according to claim 1, characterized in that the precast reinforced concrete slabs are made of concrete of a lower class in strength in comparison with concrete of monolithic belts.

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