EP4036315A1

EP4036315A1 - Construction system for footings and foundation walls, especially in the lost formwork system

Info

Publication number: EP4036315A1
Application number: EP21218037.6A
Authority: EP
Inventors: Krzysztof Zwierz
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-31
Filing date: 2021-12-29
Publication date: 2022-08-03
Also published as: PL436609A1

Abstract

The structural system dedicated to making a formwork of footings and foundation walls is characterized by the fact that it consists essentially of three elements, the assembly frame (2), modular, insulated formwork board (1) and the "U" type stirrup (3) connected with each other in defined way and repeated many times depending on the construction design to obtain the full length of a formwork. The assembly frames (2) with the width of the designed footing formwork are placed at a distance of not less than 400mm, one from the other, on the bottom of the formwork ditches, then modular insulated boards (1) are mounted to the sides (4) of the assembly frame with binding wire. In order to create a monolithic wall, prepared reinforcement of a formwork bench is sprinkled with sand and then gradually filled with concrete mass. Then, reinforcement of a foundation wall is mounted to a formwork bench by connecting subsequent elements of the assembly frame (2) with the width designed for a foundation wall with the use of a U-type stirrup (3) and attaching modular, insulated formwork boards (1) to them, creating a ready monolithic wall with the width and height in accordance with the design and ready to be filled with concrete mass.

Description

The subject of the invention is a construction system for making foundation footings and walls, in particular in the permanent formwork system for use in building construction.
The lost formwork is a formwork system that enables quick and efficient execution of a form used to give the designed shape to a concrete mix filled with reinforcement. The lost formwork is not a demountable element, after completion of concreting works, it constitutes an important component of the constructed structure, also becoming thermal insulation.
There is a known formwork from the Polish patent application No. P.390 772 , made of extruded polystyrene, preferably class ≥ 700 kPa [CS (10 \ Y) 700 acc. EN 826]. Due to the high resistance of the formwork material to long-term loads and biological corrosion, it remains "forever" under the building without the risk of crushing and changing its physical properties. The permanent formwork is prefabricated in elements.
In another known description of the patent application No. 369351 a method of building a frame structure with lost formwork is presented, where prefabricated elements forming walls with flat frames with wall filling, as well as prefabricated elements fulfilling the function of wall filling made of ästrobetuö (as lost formwork presented in the drawing of columns and beams have the form of a wall module (permanent formwork with openings), preferably with a rectangular cross-section, reinforced inside with steel bars and filled with concrete. The places of joining beams and columns located inside the flat frames are created as a result of pouring concrete on the construction site or in the cassette form. At the joints of beams and columns located outside the flat frames, there are elements in the shape of a notched shelf on the side of the joints. Corrugated shelves are the corner elements constituting the ends of vertical edges of flat frames. According to another feature of the invention, the corner elements constituting the ends of the vertical edges of the flat frames are corrugated shelves, cross-section in the form of a bent shelf. According to another feature of the invention, in the case of connections of flat frames occurring in the places of transitions of the planes of individual surfaces of the outer walls, there are triangle columns. In the patent description No. Pat. 221036 we get to know the formwork, which consists of two side polystyrene shapes (1) with a cross-section in the shape of the letter "L" made of non-absorbent polystyrene and with a compressive strength at 10% deformation not lower than 150 kPa, which are connected with each other by a polystyrene connecting piece (2) with a rectangular or cross-shaped cross-section made of polystyrene. These elements are fastened with steel ties (3), which at the same time constitute the stirrups open to the structural reinforcement of the footing, which in turn have threaded joining rings (4) attached to their ends. There is also known from the patent application for the invention No. their threaded ends with integration rings (4). In addition, spacers (6) are placed between the external and internal shuttering boards (2 and 3) and steel assembly bars are threaded through them and fixed to the supporting structure. On the other hand, the space between the external and internal shuttering boards (2 and 3) is flooded from above with concrete (1) or other load-bearing and binding material. The lost formwork to make the wall of an energy-efficient building consists of an external shuttering board (2) and an internal shuttering board (3), which are connected with steel ties (5) and assembling rings (4) mounted on their threaded ends. Moreover, between the two shuttering boards (2 and 3) there are spacers (6) with steel assembly bars threaded through them, which fasten the formwork to the supporting structure.
It is also known from the patent description P. 403918 one-sided lost formwork, which is characterized by the fact that the insulating element - lost formwork (1) is shaped (profiled), in particular by a system of grooves and indentations (3), so that the concrete filling it (2) ensure good holding of the formwork - insulation, or it contains additional elements (4, 11), fittings, pins or projections made of own or other material, so that the concrete filling them would ensure good holding of the formwork - insulation.
It is also known from US Pat. 226785 building block for permanent formwork, having side walls (10, 30, 40) adapted to contact the side walls of other fittings of this type arranged in the formwork, an inner wall (50) and an outer wall (60). The side walls (10, 30) have a cross-sectional shape composed of a sector of a circle (11, 21, 31, 41) with a radius (R) greater than the thickness (g) of the shaped piece, one end of which is in contact with the inner wall (50) of the shaped piece, and the second end is in contact with the first end of the section (22, 32, 42) the second end of which is in contact with the outer wall (60) of the shaped body. The subject of the notification is also lost formwork.
The use of a board as an element forming the shape of concrete forms has been known in construction for a long time, but only as an element forming regular shapes called formwork. Oval or other shaped formwork is made of mixed materials. In traditional systems, apart from boards, table tops, connectors, clamps, supports, nails, screws, clips and wedges are used to create the formwork. These materials are not compatible with the designed reinforcement because they are made of various materials. In addition, the traditional system of laying formwork forms required tedious, manual assembly and disassembly work, involving a very high energy of human labor.
Another disadvantage of traditional formwork was the lack of moisture insulation. Insulation in traditional formwork was achieved by spreading it with tar, which has a negative impact on the environment, and recently by wrapping the finished formwork with foil.
The aim of the present invention is to develop a whole system of elements that would enable quick and efficient production of a formwork form used to give a designed shape to a concrete mix filled with reinforcement, while at the same time protecting the formwork against humidity.
The essence of the invention is a structural system for making the formwork of footings and foundation walls, which basically consists of three elements, namely the assembly frame, modular, insulated formwork and stirrup type "U" connected with each other in a specific way and repeated many times depending on the construction design until the full length of the formwork is achieved. The assembly frames with the width of the designed footing formwork are placed at a distance of not less than 400mm, one from the other, on the bottom of the formwork ditches, then to the sides of the assembly frame they are mounted with a binding wire or a modular weld, insulated formwork boards so as to create a monolithic wall and prepared in this way the reinforcement of the formwork bench is sprinkled with sand and then gradually filled with concrete. Then, the reinforcement of the foundation wall is mounted to the formwork bench by joining subsequent elements of the assembly frame with the width designed for the foundation wall with the use of a U-type stirrup and attaching modular, insulated formwork boards to them, creating a ready monolithic wall with a width and height in accordance with the design and ready to fill the formwork with concrete mass.
Preferably, the assembly frame has a specific shape that allows it to be firmly embedded in the formwork trench and mounted on the side of the modular, insulated formwork board.
Preferably, the modular shuttering board is surrounded by a foil that provides insulation against humidity for the shuttering that will be created after pouring concrete into the shuttering.
The progress that has been made in the field of formwork is enormous, and the benefits of this, especially in terms of shortening the implementation time and cost reduction, cannot be overestimated. Complicated, multi-stage activities, which so far have been necessary for the proper execution of structural elements of buildings, in particular the appropriate assembly of formwork, have been shortened to the necessary minimum. Others, such as disassembly and cleaning of formwork, turned out to be unnecessary. In addition, thanks to the precision of workmanship and matching the formwork to a specific project, the quality of work has significantly increased.
The system according to the invention can be widely used as a system formwork of benches and walls with the already obtained moisture insulation of the benches and walls. The permanent formwork according to the invention provides insulation against moisture. The construction system according to the invention makes it easy to make any regular and oval geometric shapes for the formwork without unnecessary additional connectors and other additional, various materials.
The system according to the invention is compatible with the designed reinforcement because it is made of the same materials, i.e. steel bars. In addition, the effect of compatibility gives an additional structural reinforcement of the reinforcement of the footings and foundation walls. The applied modular, insulating formwork board provides insulation against moisture during the laying of formwork forms without any additional materials.
In addition, the formwork works are performed with the involvement of three times smaller number of employees in many shafts in the wrong term, and the mass and weight of building materials when constructing the formwork is 40 times smaller than when using traditional methods, which gives measurable benefits in transport (1 m2 of the system is 15 kg in transport). The use of the system according to the invention gives a reduction in CO2 emissions, a reduction in the use of insulators such as tar, solvents, a total reduction in the use of wood in the entire foundation construction process, no construction waste during the construction of the formwork, because the materials used form a monolith.
The subject of the invention has been presented in an exemplary embodiment in the drawing in which
Fig. 1 shows the modular, insulated formwork board (1) in a side view in the basic version with a heat-shrinkable film (6), Fig. 2 shows the assembly frame (2) in the basic version in a straight view, Fig. 3 shows a stirrup of the type "U" (3) in a straight view, Fig. 4 shows a pictorial drawing of the method of assembling the insulated formwork board (1) on the side (4) of the assembly frame (2), Fig. 5 shows a fragment of the formwork bench obtained as a result of joining the assembly frame (2) with an insulated board (1) in the axonometric projection, Fig. 6 shows a fragment of the footing form and the formwork wall obtained as a result of joining the formwork form of the footing with the formwork form of the wall by means of a U-type stirrup in the axonometric projection, Fig. 7 shows Formwork forms of the footing and walls in the exemplary embodiment in general view, Fig. 8 shows assembly frames (2) during the joining operations at the test construction site, Fig. 9 shows a set of assembly frames (2) p Fig. 10 shows the formwork boards (1) during the assembly operations on the assembly frames (2), Fig. 11 shows the installation of the U-type stirrup (3) after pouring concrete mass on the formwork bench, Fig. 12 shows the foundation wall prepared for pouring, Fig. 13 shows the footing with the foundation wall after pouring with concrete mass.
According to the invention, the construction system for forming the formwork of footings and foundation walls is characterized in that it consists essentially of three elements, namely a modular assembly frame 2, an insulated formwork board 1 and a U-type stirrup 3 connected with each other in a defined manner and repeated several times depending on the construction design until the full length of the formwork is obtained. Mounting frames 2 with the width of the designed footing formwork are placed at a distance of not less than 400mm, one from the other, on the bottom of the formwork trench, then to the sides of the mounting frame 4 are mounted with a binding wire or weld modular, insulated formwork boards 1 so as to create a monolithic wall The already prepared reinforcement of the formwork bench is sprinkled with sand and then gradually filled with concrete mass. Then, the reinforcement of the foundation wall is mounted to the formwork bench by joining successive elements of the assembly frame with the width designed for the foundation wall with the use of a "U" type 3 stirrup and attaching modular, insulated planks 1 to them, creating a ready monolithic wall with a width and height in accordance with with the design and ready to be filled with concrete mass.
The assembly frame 2 has a specific shape that allows it to be embedded in the formwork trench and mounted on the side of the 4 modular, insulated formwork board 2. The modular, insulated shuttering board 1 is surrounded by a foil that creates insulation against humidity for the formwork that will be created after pouring concrete into the formwork. A modular, insulated formwork board 1 for formwork, especially for permanent formwork, consists of a flat, board-shaped surface at least 2000 mm long made of ribbed steel bars with a diameter of at least 8 mm, the horizontal bars crossing the vertical bars at right angles. The base of the mounting frame has the shape of a triangle, square, semicircle, or perpendicular straight line at the point of connection with vertical bars, and a square or rectangular shape in the middle. In addition, the shuttering board is coated with a heat-shrinkable foil, which provides support to concrete mixtures.
The modular, insulated formwork board 1 may be available in variants of various lengths, but the most desirable in terms of weight, ease of laying and construction according to construction plans is the length of the formwork board equal to 2000mm. Such a length of the structural element allows easy formwork for both the footing and the foundation wall.
In order to make the formwork, any dimension of the reinforcement stirrups is tightened with the use of tie wire to the structural elements arranged longitudinally and perpendicularly, filled with bars according to the design recommendations, and we obtain a ready form with reinforcement for the permanent formwork. After preparing the form and arranging it, you can proceed to filling the made formwork with concrete mix.
Heat-shrinkable foil on the vertical wall of the element, it creates a very stable support for concrete mixtures and protects the concrete against erosion and the negative effects of water. The modular, insulated shuttering board is easy to use, easy to install, and above all, it is the basis for the recommended construction reinforcement. Most often, the shuttering board is at least 1500mm long, but it can also be 4000mm, 6000mm, or whatever is required by the design. The diameter of the steel bars is preferably 8mm, but for larger structures a steel bar with a diameter of 10mm or 12mm may be used.

Claims

Structural system for making the formwork of footings and foundation walls, characterized in that it consists essentially of three elements, namely an assembly frame (2), a modular, insulated formwork board (1) and a U-type stirrup (3) joined together in a specific manner and repeated many times, depending on the construction design, until the full length of the formwork is obtained, while the assembly frames (2) with the width of the designed formwork, the benches are placed at a distance of not less than 400 mm, one from the other on the bottom of the formwork ditches, then to the sides (4 ) the assembly frame is mounted with a tie wire or a weld, modular, insulated formwork boards (1) so as to create a monolithic wall and the reinforcement of the formwork bench prepared in this way is sprinkled with sand and then gradually filled with concrete mass, and then the reinforcement of the foundation wall is mounted to the formwork bench by joining successive elements of the assembly frame (2) with a design width for the foundation wall with the "U" type stirrup (3) and attaching modular, insulated formwork boards (1) to them, creating a ready monolithic wall with a width and height in accordance with the design and ready to be filled with concrete mass.
Structural system according to claim 1 characterized in that the mounting frame (2) has a specific shape that allows it to be embedded in the formwork trench and fixed on the side (4) of the modular, insulated formwork board (2).
Structural system according to claim 1 characterized in that the modular formwork board (1) is surrounded by a foil which creates an insulation against humidity for the formwork which will be created after pouring concrete into the formwork.