GB1604867A

GB1604867A - Flooring slab

Info

Publication number: GB1604867A
Application number: GB2778/78A
Authority: GB
Original assignee: NMV BUREAU ET ET CONST; Cockerill SA
Current assignee: NMV BUREAU ET ET CONST; Cockerill SA
Priority date: 1977-01-24
Filing date: 1978-01-24
Publication date: 1981-12-16
Also published as: DE2802032A1; FR2378144A1; NL7714626A; IT1092006B; IT7819190A0; NL187365C; FR2378144B1; NL187365B

Description

(54) FLOORING SLAB (71) We, CoCKERILGOVGREE-PRoVI- DENCE ET ESPERANCE-LONGDOZ, en abrege, COCKERILL, of 4100 Seraing, Belgium and BUREAU D ETUDES, ETUDES Er CONSTRUC- noNs N.M.V. of 188 Avenue Moliere, 1060 Brussel, Belgium, both Belgian body corporates, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a flooring slab.

Flooring slabs already exist which are constituted by I-beams arranged parallel to one another, loose intermediate members carried by the lower flanges of the I-beams, and concrete cast onto the intermediate members at least up to a level flush with the upper flanges of the I-beams.

In the conventional flooring slabs, the intermediate members can be plane or corrugated plates resting on the upper wings of the I-beams, whose webs are not perforated.

These conventional slabs are resistant to bending stress under a load only in the direction parallel to the beams. It is only when strong reinforcement extending transversely and below the beams is used that resistance to bending stress of the slab is also ensured in the direction perpendicular to the beams.

Furthermore, concrete arranged above the plates has a practically uniform thickness over the entire surface of the slab. Moreover, these conventional slabs are unaesthetic and require a lower finishing coating.

The present invention is concerned with a flooring slab which has, with respect to conventional slabs, the advantage of being capable of being rapidly and readily fabricated both in workshop and at a building yard by making use of light metal intermediate members without expensive and heavy tools and by employing non-specialized labour.

The invention provides a flooring slab comprising: steel I-beams arranged parallel to one another, the webs of the I-beams having respective openings which are aligned along transverse directions with respect to the Ibeams; intermediate shuttering members resting on the upper surfaces of the lower flanges of the I-beams, each shuttering member having a concavity directed downwards; transverse reinforcements in the form of concrete-reinforcing rods traversing the openings in the webs of the I-beams along the said transverse directions, the passage crosssectional area of each opening being larger than the cross-sectional area of the transverse reinforcement traversing it; and concrete cast on the shuttering members at least up to a level flush with the upper flanges of the Ibeams.

The I-beams and the transverse reinforcements impart rigidity and resistance to bending stress to the slab in any direction, such rigidity and resistance being advantageously increased by mutual connection of the concrete on both sides of the I-beams through the free spaces between the edges of the openings and the transverse reinforcements.

Furthermore, the slab has a particularly aesthetic appearance owing to its lower alveolate face. Furthermore, the slab has the advantage of being constituted by intermediate shuttering members and beams which can be easily stacked on one another and which thus are transportable and storable while occupying a reduced space.

The concavity of the intermediate shuttering members may be constituted by a cavity or recess which is delimited by a substantially spherical cap or by a substantially polyhedral cap. In practice, each intermedate member may be a stamped metal sheet.

The edge portions of the intermediate member which are not resting on the Ibeams are bent upwards at least once and form transverse stiffening members together with the edge portions of intermediate members adjacent thereto. The adjacent edge portions may advantageously be arranged one on top of the other or disposed one near the other and covered or overlapped by a transverse beam bridging them. These characteristics impart transverse stiffening and ensures tight interconnection of the intermediate members between the I-beams. Moreover, upon mounting the intermediate members while forming the slab, the worker can walk or stand on the I-beams or on the intermediate members already assembled, which facilitates and alleviates his work.

Preferably, the openings in the web of each I-beam are constituted by lower and upper openings. The lower openings are separated from one another by a distance substantially equal to the length of each intermediate member or a sub-multiple of this length. Adjacent edge portions of the intermediate members are arranged at the positions of lower openings, so that they locate respective transverse reinforcements which are thus disposed just above these edges. Preferably, the upper and lower openings in the web are arranged staggered along the I-beam.On the other hand, the lower openings may be vertically elongate and flared upwards so as ta facilitate inset tion of respective transverse reinforcements so that the latter may rest on their edges The I-beams are preferably kept spaced from one another by means of transverse crossbars before and during casting of the concrete. The cross-bars in question have the double advantage of keeping the I-beams parallel with one another during casting of the concrete, and of also serving as auxiliary transverse stiffening members.

To be particularly economic, the slab preferably has I-beams formed of alloy steel.

The invention will be described further, by way of example only, with reference to the accompanying drawings, in which: Figure I is a partial plan view of a flooring slab; Figure 2 is a vertical cross-sectional view of the slab, taken along the line 11-U of Figure 1; Figure 3 is another vertical cross-sectional view of the slab taken along the line 111-HI of Figure 1; Figure 4 is a plan view of an intermediate member of the slab; Figure 5 is a vertical cross-sectional view of the intermediate member of Figure 1 taken along the line V-V; Figure 6 is another vertical cross-sectional view of the intermediate member taken along the line VI-VI of Figure 4;; Figure 7 better illustrates the assembly of the edges of adjacent intermediate members, which edges do not rest on the beams of the slab; Figures 8 and 9 are diagrammatic views showing other ways of assembling the edges of adjacent intermediate members, which edges do not rest on the beams of the slab; Figure 10 is a vertical cross-section to a larger scale of a beam of the slab taken along the axis of a crossbar connected to this beam; Figure 11 is a partial side view of a beam of the slab; Figures 12 and 13 illustrate how to assemble the cross-bar on the beam; Figure 14 is a plan view of another embodiment of an intermediate member of the slab; Figure 15 is a vertical cross-section taken along the line XV-XV of Figure 14 and Figure 16 is another cross-sectional view taken along the line XVI-XVI of Figure 14.

In the various Figures the same numerals indicate similar members.

The slab shown in Figures 1 to 9 serves for flooring. The flooring slab is substantially constituted by concrete 1, I-beams 2, and intermediate shuttering members 3.

As shown in Figure 2, the intermediate members 3 rest adjacent to one another at their opposite edges 4 and 5 on the lower fLawes of the beams 2. Thus, after mutual assembly, the beams 2 and the intermediate members 3 form together a relatively light metal assembly into which concrete 1 is poured.

After pouring, the concrete 1 exceeds the level of the upper flanges of the beams 2.

Thus, the upper surface of the concrete 1 can be advantageously levelled out by simply moving a blade along the upper flanges of the beams. This characteristic makes it possible to easily complete the upper face of the slab.

However, the concrete 1 may extend beyond the upper flanges of the beams 2, if desired.

The beams 2 are rolled steel sections having high elasticity, weldability, and long life, available on the market under the trade name Protenax. The beams are for example 200 mm high and 60 mm wide.

Each beam 2 is formed with upper openings 6 and lower openings 7 in its web as shown in Figure 11. The upper openings 6 are horizontally aligned and are spaced from one another by a distance which is not necessarily a function of other components of the slab.

The lower openings 7 are also horizontally aligned but are spaced from one another by a distance equal to the width of a sub-multiple of the length, of the intermediate members 3.

In the example illustrated, the upper openings 6 and lower openings 7 are regularly distributed staggered along the beam 2. Furthermore the upper openings 6 and the lower openings 7 are vertically elongate, but the upper openings 6 are flared downwards, while the lower openings 7 are flared upwards.

The beams 2 extend parallel to one another and are equally spaced apart by a distance of about 600 mm. The beams 2 are longitudinally arranged in the slab.

Each intermediate member 3 is a stamped metal sheet. The sheet is made of steel of good stamping quality and is about 0-G mm thick.

Each intermediate member 3 has a concavity directed downwards when in position on the beams 2. In a first embodiment (Figures 1 to 9) the concavity of the intermediate members 3 is delimited by a bulged cap 8 szbstantially spherical in shape. The concavity in question, however, can have another shape such as that delimited by a substan tally polyhedral cap as shown in Figs. 14 to 16. The bulged cap 8 is surrounded by a e portion 9.

Each intermediate member 3 rests at opposite edges 4 and 5 on the lower flanges of the beams 2. On the other hand, the other edge portions 10 and 11 of the intermediate member 3 have a special form and are for example V-bent as shown in Fig. 6. When two adjacent members 3 are arranged side by side on the lower wings of two beams 2, the edge pertion 10 of a member 3 is placed on the edge portion 11 of the other member 3 as shown in Fig. 7. Consequently, the edge portions 10 and 11 of the two intermediate members 3 cooperate to form a transverse intermediate stiffening member.

The edge portions 10 and 11 which do not rest on the lower flanges of the beams 2 may have other shapes than those illustrated in Figs. 6 and 7. Thus, the edge portions 10 and 11 in question can be bent to form an upwardly and outwardly flared flange and can also be superimposed on one another as shown in Fig. 8. Alternatively, the edge portions 10 and 11 can both be bent to form a flange extending vertically upwards, the flanges in question being arranged one against the other and covered or overlapped by a transverse U-shaped beam 12 bridging them, as indicated in Fig. 9.

Transverse reinforcements 13 in the form of concrete-re-inforcing rods are arranged above the edge portions 10 and 11 on adjacent intermediate members 3 and close to the edge portions 10 and 11, while extending through the lower openings 7 of the webs of the beams 2 and resting on the lateral edges of the openings 7, being wedged in them to a greater or lesser extent. Each transverse reinforcement 13 has a circular cross-section whose area is smaller than the cross-sectional area of the lower openings 7 in question.

Before casting the concrete 1, the beams 2 are supported by end supports and possibly by intermediate supports and are then connected together by means of transverse crossbars 14 connecting their upper parts and keeping them at the same distance. The intermediate members 3 are then placed in position together with the transverse reinforcement 13. After casting of the concrete 1, the crossbars 14 also transversely reinforce the slab obtained. It should be noted that each crossbar 14 has a cross-sectional area smaller than the area of the upper openings 6 in the webs of the beams 2.

In the exmple illustrated, the crossbars 14 are steel rods screw-threaded at their ends and each provided with a nut 16, an elongate washer 17 fixed by weld 15, and a circular washer 18. The crossbars 14 are arranged in the upper openings 6 in the webs of the beams 2 and rest against the lower part, i.e.

the largest part, of these openings 6. Insertion of the crossbars 14 in the upper openings 6is effected with the elongate washers 17 vertically arranged as shown in Fig. 12, while fixing of these crossbars 14 to the webs of the beams 2 is obtained by tightening the nuts 15 to 16 with the elongate washers 17 horizontally placed as indicated in Fig. 13.

Grooved or toothed steel rods can be used as the crossbars.

Thus, after casting and setting of the con crete 1, a slab is obtained which is longi- tudinally reinforced by the I-beams. 2 and transversely reinforced by the transverse reinfercemeats 13 and the erossbars 14 Furthermore the slab has an uninterrupted layer of concrete 1 since the various portions of concrete are connected to erie another through the free spaces existing between the transverse reinforcements 13 and the edges of the lower openings 7 in the webs of the beams 2 as well as between the crossbars 14 and the edges of the upper openings 6 of these webs.The slab is thus characterised by rigidity to bending stress in any direction in its plane owing to the choice of its metal components and to the mutual connection of the various portions of concrete forming it.

WHAT WE CLAIM IS:- 1. A flooring slab comprising: steel Ibeams arranged parallel to one another, the webs of the I-beams having respective openings which are aligned along transverse directions with respect to the I-beams; intermediate shuttering members resting on the upper surfaces of the lower flanges of the I-beams, each shuttering member having a concavity directed downwards; transverse reinforcements in the form of concretereinforcing rods traversing the openings in the webs of the I-beams along the said transverse directions, the passage crosssectional area of each opening being larger than the cross-sectional area of the transverse reinforcements traversing it; and concrete cast on the shuttering members at least up to a level flush with the upper flanges of the Ibeams.

2. A slab as claimed in claim 1, in which the concavity in each shuttering member is delimited by a substantially spherical cap or a substantially polyhedral cap.

3. A slab as claimed in claim 1 or 2, in which each shuttering member is a stamped metal sheet.

4. A slab as claimed in any of claims 1 to 3, in which the edge portion of each shuttering member which do not rest on the lower flanges of the I-beams are bent upwards and form transverse stiffening members together with the adjacent edge portions of adjacent shuttering members.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. szbstantially spherical in shape. The concavity in question, however, can have another shape such as that delimited by a substan tally polyhedral cap as shown in Figs. 14 to 16. The bulged cap 8 is surrounded by a e portion 9. Each intermediate member 3 rests at opposite edges 4 and 5 on the lower flanges of the beams 2. On the other hand, the other edge portions 10 and 11 of the intermediate member 3 have a special form and are for example V-bent as shown in Fig. 6. When two adjacent members 3 are arranged side by side on the lower wings of two beams 2, the edge pertion 10 of a member 3 is placed on the edge portion 11 of the other member 3 as shown in Fig. 7. Consequently, the edge portions 10 and 11 of the two intermediate members 3 cooperate to form a transverse intermediate stiffening member. The edge portions 10 and 11 which do not rest on the lower flanges of the beams 2 may have other shapes than those illustrated in Figs. 6 and 7. Thus, the edge portions 10 and 11 in question can be bent to form an upwardly and outwardly flared flange and can also be superimposed on one another as shown in Fig. 8. Alternatively, the edge portions 10 and 11 can both be bent to form a flange extending vertically upwards, the flanges in question being arranged one against the other and covered or overlapped by a transverse U-shaped beam 12 bridging them, as indicated in Fig. 9. Transverse reinforcements 13 in the form of concrete-re-inforcing rods are arranged above the edge portions 10 and 11 on adjacent intermediate members 3 and close to the edge portions 10 and 11, while extending through the lower openings 7 of the webs of the beams 2 and resting on the lateral edges of the openings 7, being wedged in them to a greater or lesser extent. Each transverse reinforcement 13 has a circular cross-section whose area is smaller than the cross-sectional area of the lower openings 7 in question. Before casting the concrete 1, the beams 2 are supported by end supports and possibly by intermediate supports and are then connected together by means of transverse crossbars 14 connecting their upper parts and keeping them at the same distance. The intermediate members 3 are then placed in position together with the transverse reinforcement 13. After casting of the concrete 1, the crossbars 14 also transversely reinforce the slab obtained. It should be noted that each crossbar 14 has a cross-sectional area smaller than the area of the upper openings 6 in the webs of the beams 2. In the exmple illustrated, the crossbars 14 are steel rods screw-threaded at their ends and each provided with a nut 16, an elongate washer 17 fixed by weld 15, and a circular washer 18. The crossbars 14 are arranged in the upper openings 6 in the webs of the beams 2 and rest against the lower part, i.e. the largest part, of these openings 6. Insertion of the crossbars 14 in the upper openings 6is effected with the elongate washers 17 vertically arranged as shown in Fig. 12, while fixing of these crossbars 14 to the webs of the beams 2 is obtained by tightening the nuts 15 to 16 with the elongate washers 17 horizontally placed as indicated in Fig. 13. Grooved or toothed steel rods can be used as the crossbars. Thus, after casting and setting of the con crete 1, a slab is obtained which is longi- tudinally reinforced by the I-beams. 2 and transversely reinforced by the transverse reinfercemeats 13 and the erossbars 14 Furthermore the slab has an uninterrupted layer of concrete 1 since the various portions of concrete are connected to erie another through the free spaces existing between the transverse reinforcements 13 and the edges of the lower openings 7 in the webs of the beams 2 as well as between the crossbars 14 and the edges of the upper openings 6 of these webs.The slab is thus characterised by rigidity to bending stress in any direction in its plane owing to the choice of its metal components and to the mutual connection of the various portions of concrete forming it. WHAT WE CLAIM IS:-

1. A flooring slab comprising: steel Ibeams arranged parallel to one another, the webs of the I-beams having respective openings which are aligned along transverse directions with respect to the I-beams; intermediate shuttering members resting on the upper surfaces of the lower flanges of the I-beams, each shuttering member having a concavity directed downwards; transverse reinforcements in the form of concretereinforcing rods traversing the openings in the webs of the I-beams along the said transverse directions, the passage crosssectional area of each opening being larger than the cross-sectional area of the transverse reinforcements traversing it; and concrete cast on the shuttering members at least up to a level flush with the upper flanges of the Ibeams.

5. A slab as claimed in claim 4, in which

the adjacent edge portions of adjacent shuttering members are arranged one on top of the other.

6. A slab as claimed in claim 4, in which the adjacent edge portions of adjacent shuttering members are covered or overlapped by a transverse beam bridging them.

7. A slab as claimed in any of claims 1 to 6, in which the openings in the web of each I-beam are constituted by upper openings and lower openings, the lower openings being spaced from one another by a distance substantially equal to the length of each shuttering member or a sub-multiple of this length, adjacent edge portions of the shuttering members being arranged at the positions of the lower openings so that respective transverse reinforcements are disposed above these edge portions.

8. A slab as claimed in claim 7, in which the upper openings and the lower openings in the web of each I-beam are staggered along the beam.

9. A slab as claimed in claim 7 or 8, in which the lower openings are vertically elongate and flared upwards.

10. A slab as claimed in any of claims I to 9, in which the I-beams are spaced from one another by transverse crossbars.

11. A flooring slab substantially as described herein with reference to the ac companying drawings.