RU2052591C1 - Skeleton of many-storied block of flats - Google Patents

Abstract

FIELD: civil engineering. SUBSTANCE: floor disks are formed of module multi-void plates integrated with monolithic seams and monolithic reinforced concrete cross bars. Latter are perpendicular to each other in column outline, and reinforcement of those passes through column apertures. Monolithic cross bars have rises towards the middle of each aperture between adjacent columns. Reinforcement couplings anchored with ends in adjacent cross bars are placed in monolithic seams. Rise value in the cross bars and cross section area of reinforcement couplings are determined on the base of relations presented in invention description. EFFECT: high strength. 2 cl, 8 dwg

Description

 The invention relates to the construction, in particular to reinforced concrete frames of multi-storey residential and public buildings and structures.

 Known prefabricated reinforced concrete frame of a multi-storey building, including columns with through holes in the level of floors, floor slabs interconnected by releases of reinforcement, through tensile reinforcement and solid concrete [1] The known frame has a small specific material consumption.

 However, the well-known frame is sold only with ribbed floor slabs, which limits its use for residential buildings, and in public buildings requires the installation of suspended ceilings. In addition, the fixing of plates in the overlap is carried out only on friction and their engagement with the edges of the crossbars, which reduces the reliability of the frame as a whole.

The closest technical solution is the building frame, including columns with through holes in the level of the ceilings, reinforced concrete monolithic crossbars placed mutually perpendicularly in the sections of the columns, and flat disks of floor slabs from prefabricated panels located between transverse and longitudinal crossbars and connected with them, as well as between monolithic seams along their longitudinal faces [2]
The disadvantage of this solution is the complicated technology of their construction, due to the need to use through tensioned reinforcement of the crossbars for the length and / or width of the building.

 The purpose of the invention is to simplify the technology of work, reduce labor costs for installation, increase the rate of construction of a building and reduce the material consumption of floors.

где χ₁ 0,11 эмпирический коэффициент, учитывающий неупругие деформации монолитного бетона в стыках и перераспределение усилий между элементами каркаса;
q₁ погонная эксплуатационная нагрузка на ригель;
i_р шаг колонны;
Е_b модуль упругости монолитного бетона;
I_р момент инерции поперечного ригеля таврового сечения, сжатые полки которого образованы полками примыкающих торцов многопустотных плит.This goal is achieved by the fact that the columns are made with openings in the level of overlappings, multi-hollow floor slabs, and transverse crossbars with a rise to the middle of each span between adjacent columns, their lift value is determined from the ratio:
f _n =

where χ ₁ 0.11 is an empirical coefficient that takes into account inelastic deformations of monolithic concrete at the joints and the redistribution of forces between the frame elements;
q ₁ linear operational load on the crossbar;
i _p step of the column;
E _{b the} modulus of elasticity of monolithic concrete;
I _{r is the} moment of inertia of the transverse crossbar of the T-section, the compressed shelves of which are formed by the shelves of the adjacent ends of the hollow core slabs.

где χ₂ 0,15 эмпирический коэффициент, учитывающий податливость бетона в стыках по торцам плит;
q₂ погонная расчетная нагрузка на одну многопустотную плиту;
l $\genfrac{}{}{0ex}{}{\text{2}}{\text{1}}$ пролет плиты;
I_n момент инерции поперечного сечения плиты;
A_n-площадь поперечного сечения плиты;
l₀ эксцентриситет по высоте сечения между центрами тяжести сечений плиты и арматуры в швах;
R_s расчетное сопротивление растяжению продольной арматуры, расположенной в швах.Monolithic crossbars are equipped with horizontal through reinforcement, and floor disks are equipped with reinforcing braces located between hollow-core slabs in monolithic joints at the bottom and fixed with ends in adjacent crossbars. The cross-sectional area of reinforcing screeds is determined from the ratio:
A _s =

where χ ₂ 0.15 is an empirical coefficient that takes into account the compliance of concrete at the joints at the ends of the slabs;
q ₂ linear design load on one multi-hollow slab;
l $\genfrac{}{}{0ex}{}{\text{2}}{\text{1}}$ span of a plate;
I _{n the} moment of inertia of the cross section of the plate;
A _n is the cross-sectional area of the plate;
l ₀ eccentricity along the height of the section between the centers of gravity of the sections of the plate and reinforcement in the joints;
R _{s is the} calculated tensile strength of the longitudinal reinforcement located at the seams.

 In FIG. 1 shows a frame with coaxially placed plates in the extreme cells of the floor and with reinforcing braces in monolithic seams, forming resistant devices for the perception of pressure that occurs in the plane of the floor, plan; in FIG. 2 the same, with the transverse arrangement of plates in the extreme cells; in FIG. 3 node I in FIG. 1; in FIG. 4, section AA in FIG. 3; in FIG. 5 the same, the operation of a multi-hollow slab when exposed to a workload; in FIG. 6, section BB in FIG. 4; in FIG. 7 is a section BB of FIG. 4; in FIG. 8 the same, the work of the transverse crossbar when exposed to a vertical workload.

 The frame includes columns 1 with through openings in the level of overlap. Overlappings are formed by slabs 2, joined by monolithic joints 3 and reinforced concrete monolithic crossbars 4, placed mutually perpendicularly in the alignments of columns 1. Transverse monolithic crossbars 4 are made with a rise to the middle of each span between adjacent columns. Plates 2 of the floor 8 are multi-hollow. Through reinforcement 9 crossbars 4 is placed rectilinearly and horizontally. In the part of the overlap cells in monolithic seams 3, reinforcing rods 5 are placed at the bottom, anchored by the ends in adjacent crossbars 4. Such overlap cells are located at the extreme transverse crossbars 4 and at the transverse crossbars 4 bordering the openings 6, and thereby form persistent overlapping devices that provide perception thrust arising in its plane. Plates 2 in the cells of the floors with puffs 5, forming a thrust device in the plane of the floors, are placed parallel or perpendicular to the plate 2 in the disk of the floors without puffs.

 The building frame under load works as a single spatial structural system. The vertical work load on each floor is perceived by the overlap, which is a flat cross-beam system and redistributes to columns 1. At the same time, the force from each plate 2 due to the lateral monolithic seams 3 is redistributed to adjacent ones and transferred to the crossbars 4. When q is applied to plates 2 with a free support, they would have taken position 12 (Fig. 5), the jamming of the plates 2 at the ends in the crossbars 4 (Figs. 4, 5) restrains the deflection, as a result of which a spacer force N. I of this effort N, reinforcing braces 5 are placed in the seams 3 between the plates 2. In order to avoid the installation of reinforcing braces 5 over the entire plane of the overlap, in its extreme spans, cells, in the direction of installation of the plates 2, thrust devices are made of plates 2, provided at the seams 3 reinforcing braces 5. In this case, all longitudinal monolithic crossbars 4 included in the plane of overlap and acting as braces are included in the work on the perception of horizontal force H. Thrust devices can be made of plates 2 located in extreme spans coaxially with the rest or perpendicular to them.

When exposed to vertical load and the presence in the transverse crossbar 4 (Fig. 8) of the rise to the middle of the span between adjacent columns in the crossbar 4 there is a spacer force H ₂ . If there is a deflection under a vertical load in the crossbar 4, the sign of the force Н ₂ changes to the opposite. As a result, a significant lateral force is transmitted to the columns in the overlapping plane, causing them to shift towards the middle of the frame. To reduce the spacer force H ₂ under load to almost zero, the transverse bolts 4, in which the plates 2 are sealed with their ends, are bent to the middle of the span by an amount f _n , at which tensile forces N ₂ will never occur in the transverse bolts 4, but only insignificant spacers. For the perception of the latter, a through reinforcement 9 is placed in the crossbar 4 with a cross section sufficient for its perception. Due to the dowels 7, the end sections of the plates 2 are involved in the work of the crossbar 4, and the cross-section of this crossbar is t-shaped with compressed shelves formed by the shelves of the hollow-core slabs 2. This can significantly increase the rigidity and load-bearing capacity of the crossbar 4, to perform it without prestressing under construction conditions .

 The proposed frame is erected in the following sequence. Columns 1 are mounted, mounting bridges with formwork for the bottom of the crossbar 4 are mounted on them, on which multi-hollow plates 2 are laid in the design position. The plates 2 have open voids at the ends, and the plugs inserted into them are displaced inside the voids by the size of dowels 7. In the joints 3 between the plates 2 in the extreme spans, where required, fittings 5 are laid, and in the crossbars 4 the working fittings, including the through fittings 9. Then the crossbars 4 and the joints 3 are concreted simultaneously. After casting the required strength with monolithic concrete, dismantle the mounting bridges and formwork crossbars and carry out their rearrangement on the following section or floor.

Claims (2)

1. FRAME OF A MULTI-STOREY BUILDING, including columns with through holes in the level of ceilings for passing horizontal through reinforcement of monolithic reinforced concrete crossbars placed mutually perpendicularly in the alignment of columns, and flat disks of floor slabs from prefabricated plates located between transverse and longitudinal crossbars and connected with them and between monolithic seams along their longitudinal faces, characterized in that the through holes of the columns are combined with each other with the formation of openings for passing monolithic crossbars, Overlap formed hollow-core slabs, the crossbars have to rise to the middle of each span between adjacent columns, and overlap wheels are provided with reinforcing puffs arranged between the hollow plates to fall monolithic joints and anchored ends in adjacent cross-bars, wherein the amount of boost f _n crossbars and the sectional area A _s reinforcing puffs are determined respectively from the relations:

where χ ₁ = 0.11 & is an empirical coefficient that takes into account inelastic deformations of monolithic concrete at the joints and the redistribution of forces between the frame elements;
q ₁ - linear operational load on the crossbar;
e _p is the pitch of the columns;
E _b - modulus of elasticity of monolithic concrete;
I _p is the moment of inertia of the T-section crossbar, the compressed shelves of which are formed by the shelves of adjacent multi-hollow plates;
χ ₂ = 0.15 is an empirical coefficient that takes into account the compliance of concrete at the joints at the ends of the slabs;
q ₂ - linear design load on one multi-hollow slab;
l ₁ - span of the plate;
I _n - moment of inertia of the cross section of the plate;
A _n is the cross-sectional area of the plate;
l _o - eccentricity along the height of the section between the centers of gravity of the sections of the plate and reinforcement in the joints;
R _s - calculated tensile strength of reinforcing puffs.  2. The frame according to claim 1, characterized in that the multi-hollow slabs are located in each disk overlap in one or in mutually perpendicular directions.

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