US20210180310A1

US20210180310A1 - Building construction system with split precast horizontal floor supports

Info

Publication number: US20210180310A1
Application number: US17/186,956
Authority: US
Inventors: Mohammad Omar A. Jazzar
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-12-29
Filing date: 2021-02-26
Publication date: 2021-06-17
Also published as: US10260224B1; SA521421326B1

Abstract

The disclosed building construction system with split precast horizontal floor supports combines the strength and ease of construction of pre-cast concrete, with ease of transportation of cast-in-place concrete. The system avoids the requirement of casting difficult shapes by breaking the complex T-shape sections of prior patents into separate flat pieces. The formwork for flat pieces is simpler than that of complex items that include both long and wide components. For examine, T-shapes and cross-shapes are hard to cast and difficult to transport because these shapes do not sit flat, and thus must be supported at their ends. Instead of this complex casting and transport, the slabs are separated into shapes that can later be placed around the columns. This simulates the strength of a fully-precast system, while reducing the precast costs and transportation costs.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is continuation-in-part of PCT patent application number PCT/US19/48058, filed Aug. 26, 2019, titled Simplified Precast Concrete System with Rapid Assembly Formwork, which claims priority to U.S. patent application Ser. No. 16/122,064, filed on Sep. 5, 2018, issued as U.S. Pat. No. 10,260,224 on Apr. 16, 2019, titled Simplified Precast Concrete System with Rapid Assembly Formwork, which in turn is a continuation-in-part of U.S. application Ser. No. 15/858,589, filed on Dec. 29, 2017, issued as U.S. Pat. No. 10,094,101 on Oct. 9, 2018, titled Precast Concrete System with Rapid Assembly Formwork.

FIELD

This invention relates to the field of building construction and more particularly to a system for the rapid construction of buildings using precast structure to support and reinforce cast-in-place concrete.

BACKGROUND

The construction material of choice for modern multi-story structures is concrete. Concrete is a durable material, able to be formed into floors, walls, and columns.
Conventional cast-in-place concrete construction relies on the use of labor-intensive, time-consuming, bulky, built-in-place formwork that must be erected for each wall and column. The formwork takes up space that could be used for moving around the site in the floor below, and does so for the duration of the construction. This process alone is time-consuming. After the formwork is placed, concrete is poured within the forms. This concrete is allowed to partially cure, then the formwork is removed and after twenty-eight days, the concrete can bear its full load. The result of these delays is the slow the speed of construction.
Given the time-consuming nature of cast-in-place concrete, the concept of casting off-site arose, with the pre-cast concrete pieces being assembled on-site. While this can speed up construction, the resulting structure lacks the strength of a cast-in-place building due to weak connectivity. Expanding the size of the precast pieces can address the weaknesses caused by assembling discrete elements, but the resulting larger pieces complicate transportation.
What is needed is a system for constructing a building that combines the strength and continuity of cast-in-place construction with the rapid assembly of precast construction, while minimizing transportation difficulties caused by moving large precast pieces.

SUMMARY

The disclosed building construction system with split precast horizontal floor supports combines the strength and ease of construction of pre-cast concrete, with ease of transportation of cast-in-place concrete. The system avoids the requirement of casting difficult shapes by breaking the complex T-shape sections of prior patents into separate flat pieces.
The formwork for flat pieces is simpler than that of complex items that include both long and wide components. For examine, T-shapes and cross-shapes are hard to cast and difficult to transport because these shapes do not sit flat, and thus must be supported at their ends.
Instead of this complex casting and transport, the slabs are separated into shapes that can later be placed around the columns. This simulates the strength of a fully-precast system, while reducing the precast costs and transportation costs.
Specifically, the columns are formed as a single precast unit, the resulting column spanning multiple floors. The columns are precast in a series, with gaps for cast-in-place concrete to flow through, creating a solid, unified structure.
By forming precast columns that span multiple floors, construction of the building is simplified because each column unit is plumbed as it is set, creating a column that is plumb (vertical) across multiple floors.
The preferred column unit length—during transportation—height during construction—is three floors, or thirteen meters. This ideal dimension is reached assuming an interior height of three meters, plus is three rebar gaps of 0.3 meters each, totaling to thirteen meters. This length of thirteen meters is the standard length of a trailer, thus simplifying transportation.
Each column segment of a column is separated by a floor gap, across which bridging rebar connects the column segments.
This is the point at which the vertical columns must transition to the horizontal floors. To help carry the load between the floor and columns, a mirrored, split central member is used. The central member splits into two or more central member components. The central member components are placed on top of each column segment, partially surrounding the exposed bridging rebar.
Steel bars run continuously through each half of the column cap, also protruding outward at least one development length in all four horizontal directions.
The precast column cap mitigates severe shear stresses around columns by diffusing the stresses to a larger area while transferring moments between adjoining bays. Each half is primarily rectangular in shape, with a cut-out of a smaller rectangle near interior edge. The cutout, or gap, allows steel to pass between the precast column cap halves, the cap resting on the column segment below.
Steel stirrups embedded in the central member protrude upwards. The stirrups surround the cast-in-place rebar, creating a continuous rebar connection across the central members through to adjacent structure.
After placement of the central members, temporary structures are used to support spanning members. The spanning members are preferably a perforated, grid-shaped structure to reduce weight, appearing similar to a waffle. The cavities of the spanning member are optionally filled with foam fillers before concrete is poured. When the cavities are filled, the resulting structure requires less concrete, but maintains the bulk of its strength.
With the rebar placed, and concrete is poured over the entire floor. Special care is taken to ensure concrete flows into the floor gaps between column segments, ensuring that the bridging rebar is surrounded.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a first isometric view of the building construction system with split precast horizontal floor supports.

FIG. 2 illustrates a second isometric view of the building construction system with split precast horizontal floor supports.

FIG. 3 illustrates a view during assembly of the building construction system with split precast horizontal floor supports.

FIG. 4 illustrates a cross-sectional view of the building construction system with split precast horizontal floor supports.

FIG. 5 illustrates an isometric view showing column placement of the building construction system with split precast horizontal floor supports.

FIG. 6 illustrates an isometric view showing multiple placed columns of the building construction system with split precast horizontal floor supports.

FIG. 7 illustrates an isometric view showing a spanning member of the building construction system with split precast horizontal floor supports.

FIG. 8 illustrates an isometric view showing a structure ready for the cast-in-place concrete of the building construction system with split precast horizontal floor supports.

FIG. 9 illustrates a detail view of the columns with central members of the building construction system with split precast horizontal floor supports.

DETAILED DESCRIPTION

Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures.
Referring to FIGS. 1 and 2, a first and second isometric views of the building construction system with split precast horizontal floor supports are shown.
The hybrid concrete structure with C-shaped central member 1 includes a base member 10 at the foundation elevation. The base member 10 is topped with a column 12 that is broken into multiple column segments 14. Crossing the floor gap 17 between each column segment 14 is bridging rebar 16. The columns 12 are precast in units with multiple column segments 14, including the bridging rebar 16. Thus, when a column 12 is placed and plumbed, multiple floors are ready for construction, rather than only a single floor.
The top of each column segment 14 optionally includes a locking protrusion 18 to aid in integration of the columns 12 and the cast-in-place concrete 80 (see FIG. 4).
The central member 30 is formed from one or more central member components 32. The central member components 32 are preferably C-shaped, allowing the central member components 32 to surround the floor gap 17, while still resting against the lower column segment 14.
Each central member component 32 includes a column gap 40 formed by two or more component arms 38. The combination of column gaps 40, when the central member components 32 are placed, creates a central member recess 36.
The column member components 32 meet at a central member joint 34.
The central members 30 include rebar stirrups 50 to surround cast-in-place rebar 54. Further included is central member rebar 52 that extends outward, helping to create a unitary structure.
Referring to FIG. 3, a view during assembly of the building construction system with split precast horizontal floor supports is shown.
The hybrid concrete structure with C-shaped central member 1 includes temporary formwork used during construction.
The spanning member 60 is temporarily supported by a collapsible tower 100. Spaces between the spanning members 60 are enclosed from beneath by rotating formwork panels 110, lifted into place by rotating with respect to support rod 116 and a combination of fixed hooks 112 and slideable hooks 114.
Also visible is a column segment 14 with a central member 30 formed from two central member components 32.
Referring to FIG. 4, a cross-sectional view of the building construction system with split precast horizontal floor supports is shown.
In this figure, the cast-in-place concrete 80 has been poured, creating the unitary structure.
The cast-in-place concrete 80 now surrounds the bridging rebar 16, and has covered and surrounded the central members 30 and the spanning member 60.
In this embodiment, the spanning member 60 includes multiple cavities 64, each filled with an optional foam cavity filler 66 that prevents the cast-in-place concrete 80 from flowing into the cavities 64. This reduces the amount of cast-in-place concrete 80 that is needed, without decreasing the resulting strength.
The spanning member 60 is optionally topped with rebar mesh 68, further adding strength to the hybrid concrete structure with C-shaped central member 1.
Referring to FIG. 5, an isometric view showing column placement of the building construction system with split precast horizontal floor supports is shown.
Shown are base members 10, topped with columns 12 formed from column segments 14.
Referring to FIG. 6, an isometric view showing multiple placed columns of the building construction system with split precast horizontal floor supports is shown.
Again shown are base members 10, now all topped with columns 12.
Referring to FIG. 7, an isometric view showing a spanning member of the building construction system with split precast horizontal floor supports is shown.
The spanning member 60 is shown supported by a collapsible tower 100, the spanning member 60 placed between column segments 14 set atop base members 10.
Referring to FIG. 8, an isometric view showing a structure ready for the cast-in-place concrete of the building construction system with split precast horizontal floor supports is shown.
This view shows many spanning members 60 between a multiplicity of columns 12.
Referring to FIG. 9, a detail view of the columns with central members of the building construction system with split precast horizontal floor supports is shown.
The central members 30 are shown after placement on the column segments 14 of the columns 12, with the rebar stirrups 50 and central member rebar 52 extending upward and outward.
Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result.
It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction, and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.

Claims

What is claimed is:

1. A hybrid precast and cast-in-place structure comprising:

a precast column;

the precast column installed in a vertical position;

the precast column formed from two or more precast column segments;

the two or more precast column segments connected by bridging rebar;

a precast central member;

the precast central member installed in a horizontal position;

the precast central member formed from two or more precast central member components;

the two or more precast central member components surrounding the bridging rebar;

the two or more precast central member components resting on one of the two or more precast column segments;

wherein after assembly of the precast column and precast central member, concrete is poured across the hybrid precast and cast-in-place structure to create a unified structure;

whereby forming the precast column and the precast central member in pieces simplifies formwork requirements and transportation.

2. The hybrid precast and cast-in-place structure of claim 1, wherein:

the two or more precast central member components each include two or more component arms separated by a column gap, each precast central member component having a C-shape;

whereby the two or more precast central member components surround the bridging rebar.

3. The hybrid precast and cast-in-place structure of claim 1, further comprising:

a plurality of rebar stirrups;

the plurality of rebar stirrups protruding from an

upper surface of the precast central member;

whereby the plurality of rebar stirrups helps to create a unitary structure.

4. The hybrid precast and cast-in-place structure of claim 1, further comprising:

a spanning member;

the spanning member having a grid shape with solid sections and hollow sections;

the hollow sections including foam fillers to exclude the concrete poured across the hybrid precast and cast-in-place structure.

5. The hybrid precast and cast-in-place structure of claim 4, further comprising:

one or more spanning member rebar;

the one or more spanning member rebar protruding outward from the spanning member;

whereby the one or more spanning member rebar are surrounded by concrete when the concrete is poured across the hybrid precast and cast-in-place structure

6. The hybrid precast and cast-in-place structure of claim 3, further comprising:

a spanning member;

7. A precast structure for a building comprising:

a precast column;

two or more precast column segments forming the precast column;

the two or more precast column segments separated by a floor gap;

the two or more precast column segments connected by bridging rebar;

a precast central slab;

the precast central slab formed from two or more precast central components;

the two or more precast central components surrounding the bridging rebar;

the precast central slab installed by placement of the two or more precast central components on top of each of the two or more precast column segments, within the floor gap;

wherein after the precast column and the precast central slab are in place, then concrete is poured on top of the precast central slab, the concrete flowing into the floor gap and surrounding the bridging rebar;

whereby the precast structure is easy to transport due to separate precast columns and precast central slabs.

8. The precast structure for a building of claim 7, wherein:

the two or more precast central components each include two or more component arms separated by a column gap, each precast central member component having a C-shape;

whereby the two or more precast central components surround the bridging rebar.

9. The precast structure for a building of claim 7, further comprising:

a plurality of rebar stirrups;

the plurality of rebar stirrups protruding from an upper surface of the precast central slab;

whereby the plurality of rebar stirrups helps to create a unitary structure.

10. The precast structure for a building of claim 7, further comprising:

a spanning member;

the hollow sections including foam fillers to exclude the concrete poured across the spanning member.

11. The precast structure for a building of claim 10, further comprising:

one or more spanning member rebar;

whereby the one or more spanning member rebar are surrounded by concrete when the concrete is poured across the precast structure

12. The precast structure for a building of claim 9, further comprising:

a spanning member;

13. A method of constructing a hybrid precast concrete and p our-in-place concrete structure comprising the steps of:

placing one or more concrete base members;

placing a precast column upon one concrete base member of the one or more concrete base members;

the precast column formed from two or more precast column segments;

the two or more precast column segments connected by bridging rebar;

repeating the step of “placing a precast column upon one concrete base member of the one or more concrete base members” until all of the one or more concrete base members are topped with columns;

placing two or more precast central member components around the bridging rebar of precast columns;

the two or more precast central member components forming a precast central member;

repeating the step of “placing two or more precast central member components around the bridging rebar of precast columns” until all bridging rebar is surround by one of the two or more precast central member components;

pouring concrete across the two or more precast central member components;

14. The method of constructing a hybrid precast concrete and pour-in-place concrete structure of claim 13, wherein:

the two or more precast central member components each include two or more component arms separated by a column gap, the each precast central member component having a C-shape;

15. The method of constructing a hybrid precast concrete and pour-in-place concrete structure of claim 13, the precast central member further comprising:

a plurality of rebar stirrups;

the plurality of rebar stirrups protruding from an upper surface of the precast central member;

whereby the plurality of rebar stirrups helps to create a unitary structure.

16. The method of constructing a hybrid precast concrete and pour-in-place concrete structure of 13, the method further comprising the step of:

before the step of “pouring concrete across the two or more precast central member components”, placing a spanning member;