WO2006110104A1

WO2006110104A1 - Construction system

Info

Publication number: WO2006110104A1
Application number: PCT/SE2006/050074
Authority: WO
Inventors: Tord SJÖDÉN
Original assignee: Sjoeden Tord
Priority date: 2005-04-15
Filing date: 2006-04-12
Publication date: 2006-10-19

Abstract

A construction system for using prefabricated formwork elements for setting up building structures. The formwork elements comprise insulation and voids for casting concrete in on the construction site.

Description

CONSTRUCTION SYSTEM

Technical field

The present invention relates to a construction system, particularly to a construction system for the construction of buildings, comprising special types of casting moulds, and to a method for prefabrication of casting moulds and a method for constructing a building on the construction site by means of the casting moulds.

Background to the invention A known practice in the construction industry is the use of casting moulds for concrete. As far back as the 1960s, for example, room-sized tabular forms and storey-high wall forms made of plywood or sheetmetal were commonly used in the casting of concrete. Construction with various degrees of factory prefabrication of structural elements began in the early 1960s. Prefabricated construction mainly involved using concrete elements in multi-storey buildings, but other materials were also used.

Another known aspect of the technology is element-based buildings, i.e. buildings comprising prefabricated construction elements made at a different place than their final location. These elements are thereafter assembled on the construction site to form a building. The production of construction elements may take place in permanent factories or in temporary so-called casting yards close to the construction site. Prefabricated columns and beams are extensively used in loadbearing structures for large industrial buildings. Prefabricated surface elements, i.e. elements with extent in two directions, are used for walls, joist frames and roofs. There is also the prefabrication of box elements which may comprise one or more complete components of a dwelling, e.g. a bathroom, a kitchen or an approximately 3 metre wide section of a single-storey building. Column and beam elements are usually made of concrete, steel or wood. Surface elements are often made of concrete or lightweight concrete or with a wooden framework which is clad with, for example, gypsum board or particle board. Wall elements may incorporate windows and doors. Box elements often have a wooden framework to minimise the weight. All kinds of elements may comprise conduits for electrical, water and wastewater lines. The advantage of element-based buildings is that elements can be made in factory conditions protected from weather and wind and that buildings can be erected and completed in a short time.

The state of the art can nevertheless be improved as regards the weight and handleability of prefabricated elements. Summary of the invention

The object of the present invention is to provide not only lightweight and handleable elements but also a method for making them easily and a simple method for completing a building structure on the construction site. This object is achieved by means of a construction system which uses prefabricated formwork elements to set up building structures, where said formwork elements comprise at least one construction element itself comprising an outer panel, an inner panel, at least one spacer and fastening elements adapted to holding together said outer and inner panels so as to form one or more voids between said panels. Said spacer is adapted to spanning not the whole width of a construction panel, thus resulting in a void which runs vertically. Said fastening elements are adapted to holding said outer and inner panels together in one hole.

The outer and inner panels and the spacer are made of a material which allows them to be left in and constitute part of the wall structure after the voids have been filled with cast material. The inner and outer panels are made of a material which performs the function of an insulating material for building structures. The panels are made of EPS plastic. In an alternative embodiment, the panels are made of XPS plastic.

The invention thus comprises a construction system itself comprising prefabricated casting moulds made of permanently shaped insulating material, e.g. extruded polystyrene, so-called XPS. An alternative material is EPS. The construction system also comprises a method for making casting moulds and a method for using casting moulds on the construction site when erecting a building. The casting moulds are used as formwork for concrete and become, when the concrete has hardened, part of the finished construction element.

The construction system comprises panels made of XPS or EPS or other comparable material. Grooves about 1.5 cm deep and about 5 cm wide at between- centres spacing of 45 or 60 cm are disposed on one side of each panel. The panels measure 60 x 250 cm and are joined together in rows which are themselves joined to one another in a key and groove arrangement called masonry bond. The strips may be of any desired height less than 60 cm. A mould for casting a wall may be formed by placing two panels with their grooved sides facing one another and putting in a spacer between the grooves. Locking of the mould is by 1. bonding the spacer firmly in the grooves at each end, 2. drilling holes through the panels and spacers and pushing in a two-part sleeve from each side of the mould so that the ends of the sleeves meet in the middle of the spacer and are joined together there by thread, bayonet lock or the like. The spacers may also have holes predrilled in them to accommodate horizontal reinforcements which are supported and held in place by the spacers. Vertical reinforcements are placed in the space between the spacers and a kind of plastic plug is threaded into the other part of the sleeves so that internal battens can be fastened in to support gypsum cladding on the inside of the wall. Electrical conduits etc. are laid in the battening. Window and door apertures are prefabricated in the form of frames which are cast in on the construction site together with the rest of the walls. The function of the frame is partly to hold the window/door in place and partly to make the window/door jambs and windowsills easy to fit quickly. A "joist frame strip" is made in the form of a casting mould as described above, with cutout recesses for floor joists. Prefabricated floor joists which have a beam trimmer fitted at each end are laid in the "joist frame strip". The beam trimmers are designed in such a way that they are cast into the walls. Foundations take the form of edge beams cast under the outside walls. These edge beams are adapted to the wall sections and follow consistently the shape of the walls. The "joist frame strips" are fitted at the upper edge of the edge beams, the joists are laid in situ. Thereafter the walls can be fitted in situ. If the building is to have an upper storey (and this also applies to single-level structures with pitched roofs), a "joist frame strip" is fitted at the upper edge of the wall and the joists are laid before the casting operation. In addition to being extremely rational, the floor joists thus brace the walls, with the result that the latter need only a minimum amount of bracing.

On the basis of the above principles it is possible to prefabricate fully reinforced casting moulds with internal battening for gypsum cladding. The size of the prefabricated elements may be up to about 2.5 m high and about 5 m wide. Only in exceptional cases will such an element weigh more than 125 kg (depending on the number of windows/doors fitted in the wall element). A wall section measuring 5 x 2.5 m (12.5 m²) with no windows but with internal battening weighs about 104 kg. The low weight makes it possible to use towing devices whereby wall elements can be towed from factory to construction site by an ordinary passenger car. No crane assistance is needed on the construction site for placing the elements in position.

Advantages of the system:

The building will not be liable to moisture damage. XPS is approved as a moisture barrier.

Advantageous weight, low transport costs. - Very low operating costs.

Almost no maintenance needed.

Minimum heating costs.

Short construction times. Brief description of the drawings

The invention is described below in detail with reference to the attached drawings, in which:

Fig. 1 depicts as viewed from above a wall comprising wall elements according to an embodiment of the present invention.

Fig. 2 depicts a joist frame element according to an embodiment of the present invention.

Fig. 3 depicts cellular plastic strips for planar wall elements.

Fig. 4 depicts cellular plastic strips for wall corner elements. Fig. 5 depicts in profile a partly completed wall using wall elements, edge beams and joist frames.

Fig. 6 depicts a detail of the joining together of two wall elements.

Detailed description of preferred embodiments Fig. 1 depicts as viewed from above part of a wall structure involving casting mould elements 101-105 according to an embodiment of the invention. A planar wall element 102 comprises an outer panel 110, an inner panel 112 and a number of spacers 114 disposed between the inner panel 112 and the outer panel 110 so as to leave a number of voids 120 running vertically. The voids 120 are intended to be filled on the construction site with concrete in order to give the final building its structural strength and durability.

The spacers 114 have a vertical extent which is less than the vertical extent of the panels 110, 112, resulting in the formation of horizontal voids which can be filled with concrete and thereby further improve the strength of the structure. The casting mould elements 101 - 105 are each further provided with a hole

130 adapted to penetrating the outer panel 110, the spacer 114 and the inner panel 112. The hole 130 is adapted to providing space for a two-part sleeve which is with advantage applied by one portion of the sleeve being pushed in from each side of the casting mould element so that the ends of the sleeves meet in the middle of the spacer 114, where they are joined together by thread, bayonet lock or similar method.

The purpose of the sleeve is partly to serve as a fastening for battens (see below) and partly to clamp firmly the spacers 114.

In an alternative embodiment, the spacers are also fastened by adhesive bonding.

The spacers 114 are also provided with predrilled holes for accommodating horizontal reinforcements which are supported and held in place by the spacers. Vertical reinforcements are preferably disposed in the space between the spacers. Plastic plugs or other anchoring elements are disposed inside the two-part sleeves so that internal battens 140 can be fastened in.

In the course of construction, the battens are intended to serve as mountings for gypsum panels or similar kinds of backing for internal wall cladding in a known manner. Electrical conduits etc. may also be laid in the battening in a known manner.

Two wall elements are joined together by a key and groove connection 150.

The panels 110, 112 are made with advantage of the insulating material extruded polystyrene (XPS), which affords advantages from the moisture point of view, since XPS is approved as a moisture barrier. XPS is also advantageous from the weight point of view, since it is very light.

Fig. 2 depicts a joist frame 200 comprising lightweight battens 250 and permanently shaped insulating material 210, 220, 230, 240, 242, 244 whereby the lightweight battens 250 are disposed in recesses in a joist frame upper panel 210 and in a joist frame lower panel 220. Blocks 230, 240, 242, 244 of said permanently shaped insulating material are placed in the resulting voids.

Fig. 3 depicts a wall panel 300 provided with grooves 310, 320, 330 for spacers 114. The grooves are with advantage disposed in such a way as to match with standardised between-centres distances of 450 and 600 mm.

The distance between the grooves 310 and 320 is adapted to being half the between-centres distance, i.e. 225 or 300 mm. The distance between the grooves 310 and 330 is therefore adapted to being 450 or 600 mm. The distance from an edge of the wall panel to the first groove is adapted to being half of half the between-centres distance, i.e. 112.5 and 150 cm respectively.

Figs. 4a and b depict an outer corner panel 400 and an inner corner panel 410 provided with grooves 402, 404, 406, 408 for spacers 114.

Fig. 5 depicts in profile a partly completed building structure comprising wall elements, edge beams and joist frames.

Fig. 6 depicts a detail of how two wall elements are joined together.

The foregoing description is mainly concerned with embodiments of the invention used for constructing walls. It is however also possible to use prefabricated formwork elements for constructing floor joist frames with suitably disposed holes for filling with concrete. Casting in the case of multi-storey buildings entails using shores.

Claims

1. A construction system for using prefabricated formwork elements for setting up building structures, characterised in that said formwork elements comprise at least one construction element (102) itself comprising an outer panel (110), an inner panel (112), at least one spacer (114) and a fastening element adapted to holding together said outer and inner panels so as to form one or more voids (120) between said panels (110, 112).

2. A construction system according to claim 1, whereby said spacer (114) is disposed to span not the whole width of a wall panel, thus resulting in a void (501) which runs vertically.

3. A construction system according to claim 1, whereby said fastening element is adapted to holding said outer and inner panels together in one hole (130).

4. A construction system according to claim 1, characterised in that said outer and inner panels are made of a material which can be allowed to remain in place and constitute part of the wall structure after the void has been filled with cast material.

5. A construction system according to claim 4, whereby the outer panel (110) and the inner panel (112) are made of a material which performs the function of an insulating material.

6. A construction system according to claim 4, whereby the outer panel (110) and the inner panel (112) are made of EPS plastic.

7. A construction system according to claim 4, whereby the outer panel (110) and the inner panel (112) are made of XPS plastic.

8. A method for making prefabricated formwork elements according to claim 1, comprising the prefabricated formwork elements being made up of pretreated panels.

9. A method for erecting a building, characterised in that prefabricated formwork elements according to claim 1 are used as casting moulds on the construction site.