EP0815330B1

EP0815330B1 - A composite slab element

Info

Publication number: EP0815330B1
Application number: EP96902293A
Authority: EP
Inventors: Yrjö Kalevi Wederhorn
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-02-14
Filing date: 1996-02-14
Publication date: 2000-10-25
Anticipated expiration: 2016-02-14
Also published as: FI96898C; DE69610762T2; DE69610762D1; ATE197184T1; EP0815330A1; WO1996025566A1; FI96898B; AU4666196A; FI950641A0

Abstract

A composite slab element comprised of a cast portion (1), e.g. concrete, cast reinforcement (2), e.g. a steel net, possible intermediate purlins (5) and joists (8). A single joist has at least two parallel ranged joist elements (8), between which a metal sheeting (4) is placed, whereat the edge of the metal sheeting extends from the joist element to the concrete and the metal sheeting functions both as a composite and a reinforcement part.

Description

The invention relates to an industrially produced composite slab element according to the first part of claim 1.

Such a slab element is known from SE-A-443598.

Slab elements are used mainly as base, intermediate and upper floors in detached houses, terraced houses, small apartment houses and indutrial halls. With the concrete side mounted downward, the element is also well adaptable as a s.c. Radon preventing base floor.

Other load-bearing floor constructions made by known technology hollow-core concrete slabs and TT slabs and floor structures of different composite slab constructions are known from the FI publication prints 66229 and 60752 as examples. Their disadvantages are :

the concrete slabs are quite heavy and not applicable to timber-framed buildings
due to heavy weight, the transportation and the handling of concrete slabs at site is complicated and expensive
normally, present floor structures of composite slab constructions are cast under site conditions, where either flat or profiled sheet metal must be used as casting base/mould
usually, the effective span of present floor structures of composite slab construction does not exceed 6 metres
frame elements of mere wood, to which composite parts are fixed for the sealing compound, must in most cases be straightened at site, since wood tends to twist and warp. Possible pre-elevation must be done at site
using a s.c. Homegon composite slab and a corresponding method, the slab becomes heavy, since the concrete in the profiled portion does not function effetively, and making thermal and sound insulation, heating, plumbing, air conditioning and electric installations are complicated and expensive.

The object of this invention is to remove the above disadvantages and to produce a composite slab element, by which a light and strong construction is achieved.

The composite slab element according to the invention is characterized by the features mentioned in claim 1.

The advantage of the invention is, in the first place, the simplification of manufacture compared with previously known technology. It is also an advantage that a significantly longer effective span and a lighter construction are achieved, due to which the element transportation and handling costs are reduced. A further significant advantage is also the space left between the joists, allowing heating, plumbing, air conditioning and electric installations as well as sufficient sound and thermal insulation. Through pre-stamped openings in the sheeting, transverse heating, plumbing, air conditioning and electric installations can be done. The ease of making stair and other openings can also be considered an advantage, as well as the soffit of joists functioning as studs and to which different roofing materials can be directly fixed by nails. In addition, a significant advantage is reached in fire protection, since the location of the composite and reinforcement metal sheeting is between fire-retardant wooden parts.

Balkonies, bay windows and other corbels can be made very easily. To prevent heat conduction at the through hole, sheeting is removed from a distance of ab. 50 mm.

In the following the invention is disclosed with reference to the enclosed drawings where,

Fig. 1 shows a perspective view of the slab element.

Fig. 2 shows a cross-section of the slab element.

Fig. 3 shows a lengthwise section of the slab element.

Fig. 4 shows the slab element turned upside down.

Fig. 5 shows a load-bearing joist as per the invention.

Figure 1 shows a composite slab element according to the invention comprising a concrete cast portion 1 including a steel net as reinforcement 2 of the construction. Under the concrete slab, at a distance from each other, there are joists, both of them made of two wooden joist elements 8, between which a metal sheeting 4 is pressed. The metal sheeting has prongs 7 on both sides, the sheeting reaching to the lower edge of the joists and the upper edge of sheeting 4 protruding from between the joist elements 8 to the concrete.

The continuous sheeting 4 in the element attaches the wooden joists to the concrete. Most conveniently, the element has also an intermediate purlin 5 transversal between the joists.

The element is manufactured in that in the first stage the cut-to-size joist elements 8 and the sheeting 4 are pressed together. In the second stage the joists are connected for a certain spacing and the intermediate purlins 5 fixed in place.

In the third stage a sealing compound is casted as a layer of appr. 50 mm into a mould having a demountable edge and levelled by vibration. A steel net 2 is then mounted on the sealing compound, whereafter the joist frame with intermediate purlins is put on reinforcement 2 in the sealing compound, vibrated and pressed into the concrete till the sheeting has sunk 25 mm and intermediate purlins ab. 2 - 3 mm into the concrete. The element is then left to cure and to become solid.

Figure 2 shows the element from the rear and partly sectioned and figure 3 shows a side view of the same element, partly sectioned. In sheeting 4 openings 6 are made spaced from each other, through which transversal plumbings and wirings are possible.

In figure 4 the element is upside down and in this position applicable for installation as a base floor and, for instance as an embodiment, to prevent Radon hazards due to its dense structure.

Figure 5 shows an example of a joist applicable in conjunction with the invention. A great bearing capacity is reached by making the joist of several elements using two

sheetings

4 and 14. The upper part 13 of sheeting 4 reaches into the cast portion 1. Joist

elements

8 and 9 of joist upper part are joined together by sheeting 4, whereat plywood web 10 is also engaged with the upper part. The joist lower part is assembled by means of sheeting 14, into which

elements

11 and 12 and web 10 are pressed. Most conveniently, the

elements

8,9,11 and 12 are of wood.

The invention is not limited to the above presented embodiment examples only, but many modifications are possible within the limits of the claims. Different materials can be used for the framework, such as plastic, glass fibre and different board structures, as well as production of the slab element without intermediate purlins.

Claims

A composite slab element comprising a cast portion (1), e.g. of concrete, a cast-in reinforcement (2), e.g. a steel net, joists and possibly intermediate purlins (5), characterized in that at least one joist comprises at least two parallel joist elements (8,9,10,11,12), between which a metal sheeting (4) is placed, the edge (13) of the metal sheeting extending from the joist to the cast portion (1), such that the metal sheeting functions both as a connecting part and a reinforcement part.
A composite slab element according to claim 1, characterized in that the joint between the joist elements, the concrete and the metal sheeting is achieved by means of prongs (7) stamped out from the sheeting.
A composite slab element according to any of claims 1 or 2 characterized in that the metal sheeting extends from the cast portion (1) to the lower edge of the joist.
A composite slab element according to any of claims 1 or 2 characterized in that the joist is comprised of a plurality of joist elements (8,9,10,11,12) and a plurality of element-combining sheetings (4,14), whereby the uppermost sheeting (4), in use extends into the cast portion (1).