Op or Tune Technical Description

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B

The slab

in wooden boards

TechnicalDescription

Principle fundamental

Structural Aspect

Architectural As ect

Economic Aspect

Physical and acoustic aspect

o

Ecological aspect

International patent and registered trademark


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TABLE OF CONTENTS

1 GENERAL CONCEPT 4

1.1 Presentation 4

1.2 Principe Fundamental 4

2 STRUCTURAL ASPECTS 6

2.1 Predesign 6

2.2 Behavior in case of fire load 6

2.3 Analysis in case of fire load 6

2.4 Behavior in case of earthquake 8

3 ARCHITECTURAL ASPECT 8

3.1 A very punchy aspect 8

4 ECONOMIC ASPECT 9

4.1 A simple concept 9

5 PHYSICAL AND ACOUSTIC ASPECTS 9

5.1 Building physics 9

5.2 Acoustic Aspect 9

5.2.1 Airborne noise 10

5.2.2 Impact noise 13

6 ECOLOGICAL ASPECT 14

6.1 Consumption, balance and proximity 14

6.2 Wood from sustainable forests 14

APPENDICES 15

Appendix 1 : Renovation of a home, Ardennes (L) 15

Appendix 2 : Center for handicaped persons, Origlio (CH, Tessin) 16

Appendix 3 : National exposition in Switzerland, Expo 02 17


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Technical description

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o1 GENERAL CONCEPT

1.11.11.11.1 PresentationPresentationPresentationPresentationThe O'portune1 timber slab is a new designed application in the scope ofhorizontal timber structures. It meets high mechanical requirements andachieves spans up to 12 m.

1.21.21.21.2 Principe FundamentalPrincipe FundamentalPrincipe FundamentalPrincipe Fundamental

The principle of O'portune timber slab is based on two ideas :

First, the solid wood planks, coming directly from the sawmill, are nailedor screwed together shifted against each other in order to increase the

static height. Common cross sections for the planks are used, such as40/200 mm to 75/225 mm, with a common length of four or fivemeters.

Based on a cross section of 75/225 mm, the static height can beextended from 225 mm to 375 mm, which gives an inertia for bendingstrength twice as high as the original.

Secondly, in order to create a partial isotropic slab, which is moreefficient to support concentrated live loads by stress diffusion in alldirections, a LVL (Laminated Veneer Lumber) panel is screwed across thelongitudinal plank axis. The LVL panel thickness is designed in function

of the concentrated loads, optimizing the planks height.If the slab is subjected only to distributed loads the LVL panel can bereplaced by an OSB (oriented strand board) panel.

This kind of timber slab can be prefabricated in a carpentry hall and joinedtogether to the final size at the construction site.

The longitudinal joints provide a structural continuity, thus also bendingmoments above the supports can be taken, and a continuous monolithicstructure is accomplished. Using compression hardwood pieces in thecompression zones, the inferior planks, are reinforced. In the traction zonesfilling elements together with a more intensive screwed Kerto panel abovereinforce the superior planks.

1 Copyright, invented by Jean-Luc Sandoz


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The following pictures show offshore timber platforms on the lakes ofNeuchtel and Bienne in Switzerland, erected in 2000. The planks with across section of 60/210 mm, are four and five meters long and coveredwith an LVL panel type Kerto Q 27 mm providing a free span of 6.10 m.

Distributed load : 500 kg/m2

Punctual load (truck) : 4 x 75 kN + 300 kg/m4 x 75 kN + 300 kg/m4 x 75 kN + 300 kg/m4 x 75 kN + 300 kg/m2222 distributed load

Figure 1 : Photos of the offshore platforms of the EXPO 02 in Switzerland based on O'portune desks of 6m spanon iron posts. These platforms withstanded 30t trucks and 60t mobile cranes.

These platforms were employed for attractive architectural projects for theSwiss national exhibition: The Expo.02 that Switzerland organized in 2002.Altogether, for the two platforms 10000 m3 of sawn planks, 1200 m3 ofKerto and more than two millions of screws were employed. The entireplatform is dismantled after the event, in 2003 and all timber materials willbe re-used in classical constructions.

Figure 2 : Example of the assembling of two prefabricated O'portune blocks of the Expo 02


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o2 STRUCTURAL ASPECTS

2.12.12.12.1 PredesignPredesignPredesignPredesignThe O'portune slab is dimensioned for different types of loads. Thefundamental analyses calculate the deformations (instant and final) andbending stress. For housing application also the resonant frequency, whichmight be determinant.

When the slab is designed the number, kind and repartition of connectors(screws or nails) will be determined after the sheer stress analysis in thecomposed section.

The zone where the boards are crossed is of big importance for

optimization reasons in regard of the disposal of the connectors, whichmight obtain a fire resistance of R60 or more.

2.22.22.22.2 Behavior in case of fire loadBehavior in case of fire loadBehavior in case of fire loadBehavior in case of fire load

The system of the O'portune slabs with its central kern of 80 to 100mm isvery fire resistant. With 60mm wide boards it reaches straight R60. Whenassuring that the void on the top of the slab is properly enclosed, thesestructures can achieve R90 or R120. The zone where the boards are crossedand the disposal of the connectors are designed to stay operant for thetime of the fire attack.

The different phases of combustion and the resting cross sections after30min or 60min are shown and explained in the D-Dalle description (wood-concrete composite system)

2.32.32.32.3 Analysis in case of fire loadAnalysis in case of fire loadAnalysis in case of fire loadAnalysis in case of fire load

In case of accidental fire attack the analysis is achieved by considering0,8 mm/mn combustion of the wooden parts (0.7 mm/mn when usingDUO boards).

The down-side boards are the first to carbonize until they reach the kern

(zone where the up-side and down-side boards are doubled).With a kernal zone of 90mm, the fire resistance is at least 100min. Theresidual cross section like shown in figure 3 and 5 is analyzed for loads incase of fire (accidental situation).

With this residual cross section and 15m span the bearing capacity of theslab is still of about 500 kg/m2 (350 kg/m2 of dead load and 150kg/m2 oflive load) after 100min of combustion


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Notice that the wooden part of the slab protects in case of fire from thebottom side the upside part and the concrete. Not only the concrete staysworking, because of low temperatures, the slab also allows evacuations onthe upside. The O'portune slab so acts as are fire barrier.

Figure 3 : Initial cross section of the O'portune standard slab

Figure 4 : Cross section after 30min combustion on the down-side part

Figure 5 : Cross section after 60min combustion on the down-side part.A new cross section is obtained which

will be analyzed for the fire load


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o2.42.42.42.4 Behavior in case of earthquakeBehavior in case of earthquakeBehavior in case of earthquakeBehavior in case of earthquake

The ideal behavior of the O'portune slab during an accidental earthquakeexposure is guaranteed by a sliding bearing realized through :

long screws which allow the construction a ductile behavior

oval holes in the iron parts in the primary supporting structure

3 ARCHITECTURAL ASPECT

3.13.13.13.1 A very punchy aspectA very punchy aspectA very punchy aspectA very punchy aspect

The architectural feature of an O'portune slab in an interior is extremelyexpressive by the visible offset boards which create the ceiling.

When the typical ceiling is systemized like for example in figure 6 theparameters defining its architecture are :

The thickness of the boards

The offset of the boards

The finishing (natural or painted) of the boards

Cuts near the bearings to realize negative cornices

Indentation realized after motifs

Hard wood insertions

Integration of lights

The type of boards (simple or finger jointed dimension lumber boards,DUO boards or alternating species for a natural zebra effect)

Figure 6 : Example for a ceiling obtained with anO'portune slab with the offset boards


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4 ECONOMIC ASPECT

4.14.14.14.1 A simple conceptA simple conceptA simple conceptA simple conceptThe economy of the O'portune slab for great spans (8m 12m) isguaranteed by its basic concept which integrates the multi functionality ofslab and ceiling and its lightness of 80 kg/m2 to 120 kg/m2, which allows tooptimize the bearing reactions and further the design of the walls andfoundations.

Based on the use of dimension lumber boards and a system of very simpleconnectors the economy is guaranteed by :

The cost of the wood (finished, built-in) from 500/m3 to 700/m3

according to requirements (i.e. 80/m2

to 120/m2

) A pre fabrication of transportable slab partitions, a dry and fast placing

(up to 500m2/day) and therefore a perfectly managed transfer.

When an even more economic solution is required, the O'portune slab canbe lightened by becoming partial with (O'portune-) beams made of five toseven boards filling 20 to 40% of the slab, the rest is being coffered (seedescription Solivium slab).

5 PHYSICAL AND ACOUSTIC ASPECTS

5.15.15.15.1 Building physicsBuilding physicsBuilding physicsBuilding physics

Concerning the physical behavior of this slab, the mass of wood(ca. 0.2m3/m2) is very interesting for the thermal inertia of its volume.

In winter, the wooden part works as an isolation against deeptemperatures, while in summer it isolates against higher outsidetemperatures. As a flat roof this behavior is very favorable for the interior.

5.25.25.25.2 Acoustic AspectAcoustic AspectAcoustic AspectAcoustic AspectMoreover, wooden slabs used in simple housing are very sensibleconcerning acoustic phenomena, which have to be distinguished intoairborne noise and impact noise.


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5.2.1 Airborne noise

From one point of view, the profile of the slab is already a sound absorbingceiling.

Laboratory tests in completely reflecting halls have been effected at thePolytechnic University of Lausanne, Switzerland, with different profiles forthe wooden part, simple or improved with an acoustic isolation.

These are the three tested profiles :

Model 1, the profile simple wood like shown in figure 7 :

Figure 7 : Profile of the O'portune slab without acoustic absorber tested for airborne noise

Model 2, the wooden profile with a band of rock wool (20mm) placedon the bottom side as shown in figure 8 :

Figure 8 : Profile of the O'portune slab improved with a band of isolatingrock wool on the bottom side, tested for airborne noise

Model 3, the wooden profile with a band of rock wool (20mm) plus ahidden board as shown in figure 9

Figure 9 : Profile of the O'portune slab improved with a band of isolating rock wool onthe bottom side and a coverage on the isolation, tested for airborne noise


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The obtained results are shown in figure 10 and 12 where the value ofabsorption s ( Sabine) is given in function of the spectrum of frequencies.

Figure 10 : Acoustic performance of model 1 (no acoustic isolation)

Figure 11 : Acoustic performance of model 1 (with acoustic isolation)

Figure 12 : Acoustic performance of model 1(with acoustic isolation and an additional board)


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oTable 1 gives the values obtained for each type of frequency.

Table 1 : Absorption value for model 1 to 3 in function of frequency

It is remarkable that model 1 shows already superior behavior with an s

from more than 0,3 in the frequency range from 550-1000Hz.This coefficient is raised to a value of more than 0,6 for the same frequencyrange for model 2.

If the acoustic performance must settle even higher claims, the profile canbe widened from closed type (figure 7) to open type (figure 10). This profilehas a acoustic comportment equal to model 2 and 3.

Figure 13 : Cross section of an open O'portune


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5.2.2 Impact noise

For improving the acoustic comportment of the O'portune slab concerningimpact noise, a multi layer spring system (mass-spring-mass) must berealized.

Figure 14 shows a type of profile which integrates on the upside planeboard an acoustic absorber (20 to 40mm, wood product (Pavatex,)), astiff layer like a screed of 60 to 80mm (allowing to even integrate a floorheating system) and a final floor placed straight on the screed or on a felt.With this kind of composition the demands of new acoustic norms can besettled.

Figure 14 : Section of a O'portune slab with a hard- soft-hard system,which allows absorption and elimination of impact sound


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o6 ECOLOGICAL ASPECT

"Producing a 100m2 slab, with 10m free span, rather in wood than in

reinforced concrete, that is about 30to less of CO2 in the atmosphere."

6.16.16.16.1 Consumption, balance and proximityConsumption, balance and proximityConsumption, balance and proximityConsumption, balance and proximity

The O'portune slab has an extreme favorable balance regarding the twoenvironmental criteria energy and CO2.

In comparison to a reinforced concrete slab (concrete and steel), wood asbeing a storage of CO2 and the feedstock dimension lumber board havingthe lowest level of refinement, the energetic costs are very low, even nearly

null, when considering that the chippings can be used for heating.

Moreover its lightness allows to diminish vertical structures (walls) andfoundations; always interesting from an energetic point of view.

6.26.26.26.2 Wood from sustainable forestsWood from sustainable forestsWood from sustainable forestsWood from sustainable forests

Wood used to construct O'portune slabs is not only local wood, but alsowith certified derivation and guaranteed traceability to assure that thewood is exploited from sustainable managed forests. Therefore theecological labels are FSC, PEFC or Q+(for Switzerland).


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Appendices

APPENDIX 1 : RENOVATION OF A HOME,

ARDENNES (L)Owner : Commune de Paliseul

Architect : Ch. Lievens

Engineer : CBS

Exterior aspect

Slab with spruce boards from the Ardennes 42 x 218 mm with camber and bearings on iron

profiles. Interior aspect before and during placing

General aspect after the placing of the slab with a freespan of 12m and a length of 12m


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Technical description- Appendices

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oAPPENDIX 2 : CENTER FOR HANDICAPED

PERSONS, ORIGLIO (CH, TESSIN)

Owner : Fattoria OtafArchitect : Sven Pancera CH-Lugano

Engineer : CBT, St-Sulpice

Implementation : Xilema, Origlio (TI)

Placing of the slab on the timber frame

Interior aspect of the placed slab


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APPENDIX 3 : NATIONAL EXPOSITION INSWITZERLAND, EXPO 02

Owner : Expo 02

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