WHERE IDEAS CAN GROW. Cross-laminated timber Technical Data

WHERE IDEAS CAN GROW. Wood is naturally CO2-neutral and energy-efficient in all respects. As a building material, its positive properties help protecting against heat in summer and cold in winter. Its CO2-saving capacity significantly contributes to protecting our environment. If you use wood for building work you make a valuable contribution to the protection of the climate and the environment. In Austria, one cubic metre of new wood grows each second. One cubic metre of wood keeps one ton of atmospheric CO2 and thus helps to reduce the burden on our environment. A mere 10% more wood constructions...

MMcrosslam Products of Mayr-Melnhof Holz MM masterline Glulam beams Esteemed Customer, Thank you for your interest in our products. Please note that this document is a sales brochure and that the quoted figures are merely reference values. The document may contain typing errors and other mistakes. In preparing this sales brochure, all information was researched with due diligence. However, we cannot accept any liability for the accuracy and completeness of the figures and data stated therein. Any legal claims due to the use of this information are therefore excluded. The content of the services...

crosslam is a large-format solid wood board with a multi-layer, crosswise-oriented profile. Structure and manufacture Finger-jointed and planed lamellas are loosely laid next to each other and the flat surfaces of the layers glued at right angles to one another. The structure is made up of at least 3 layers and would typically have a symmetrical layout. The layers are pushed together laterally to dimension before applying pressure in order to obtain a gap-free surface. To avoid uncontrolled stress cracks, the narrow sides are not glued. Gluing Depending on the requests of our customers we offer...

Structure and loads of CLT elements CLT elements and / or as slabs. can be exposed to loads as panels Panel stress Slab stress: Due to their structural profile, CLT elements have different levels of stiffness in orthogonal direction to each other (orthotropic panels). In case of stress in the direction of the panel level (slab stress), only panel layers with fibre directions running parallel to the observed direction of force may be taken into account. In order to determine their load-bearing characteristics during bending movements, only those panel lamellas are taken into account that run into...

Calculation principles The dimensioning of CLT components made of can be performed according to EN 1995-1-1 and EN 1995-1-2, taking account of Annexes 2 and 3 of ETA – 09/0036. Principles and national specifications for the dimensioning of CLT are included in Annex K of ON B 1995-1-1:2015. In any case, the dimensioning of CLT components must be performed under the responsibility of an engineer who is familiar with solid panel-shaped wooden construction elements. The stresses and resistances of the profile depend on the panel structure, the structural system as well as external influences. Possible...

Total strength All data refers to a 1 m wide panel strip. Aful| total cross-section Anet cross-section value for the proof of compressive strength values in the directions of the panel layers I inertia moment of the full cross-section - as comparative value Ieff effective inertia moment in the direction of the top layers for single-span girders Iff /1 ratio indicating to what extent cross layers change the effective inertia

For calculating the characteristic cross-section values, only panels may be taken into account that are arranged in the direction of the mechanical stress. For dimensioning construction components made of cross-laminated timber according to EN 1 995-11:2015 and B 1995-1-1:2015 the characteristic strength values and elasticity constants of ETA - 09/0036 / Annex 2 must be used (see table on the right-hand side). As regards multi-axis, spanned cross-laminated timber panels, different stiffness value in the orthogonal load-bearing directions must be taken into account. The effective rigidity depends...

Material key values of panel stress according to ETA-09/0036 Characteristic

Slab stress In case of stress on the panel level, we must distinguish between the below models. Girder dimensioning t, Thickness of board layers in stress direction tj Thickness of board layers at a right angle to the stress direction Vd = Design value of shear force For dimensioning cross-laminated timber elements as girders placed in upright positions, the following equations may be used on the conditions of the technical column theory. Bending strength and bending stiffness may be calculated with the full cross-section of the board layers in the load-bearing direction. For calculating shear...

Slabs as buckling bar For dimensioning cross-laminated timber elements as buckling bars, only lamella layers in parallel to the direction of force must be taken into account. The buckling analysis can be carried out taking account of the cross-sectional structure according to the equivalent member method set forth in EN 1995-1-1:2015. The slenderness must be limited to 7 = 150. CLT elements are used to build shear areas in ceilings and walls. The shear stress due to slab shear stress can be calculated according to B1995-1-1:2015. Material key values of slab stress according to ETA-09/0036

By using crosslam kCLT elements, high requirements with regard to the fire resistance of ceilings and walls can be fulfilled. In order to proof the load-bearing capacity in case of a fire, the residual cross-section of a component according to the required fire resistance time must be referred to. This proof must be given in the extraordinary dimensioning situation according to EN 1995-1-2 with the method of a reduced cross-section. In addition, a layer thickness of d0 = 7 mm (with reduced strength and stiffness) must be discounted from this cross-section. Charring rates In order to establish...