NATIONAL ANNEX TO STANDARD. SFS-EN EUROCODE 5: DESIGN OF TIMBER STRUCTURS Part 1-1: Common rules and rules for buildings

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1 ANNEX 16 NATIONAL ANNEX TO STANDARD SFS-EN EUROCODE 5: DESIGN OF TIMBER STRUCTURS Part 1-1: Common rues and rues for buidings Preface This Nationa Annex is used together with standard SFS-EN :2004. This Nationa Annex gives: a) Nationay determined parameters for the foowing causes of EN where a nationa choice is aowed (2)P (1)P (1)P (8) - 7.2(2) (2) (4) (7) (7) (1) (3) (4) b) Guidance on the use of the Annexes A, B and C. In respect of mandatory reference standards under preparation, their atest pren versions are appied.

2 Load-duration casses (2)P Exampes of oad-duration assignment are given in Tabe 2.2(FI) beow. Tabe 2.2(FI) Exampes of oad-duration assignment Load-duration cass Permanent Loading Sef-weight Machinery, equipment and ightweight partition was fixed permanenty to the structure Earth pressure Long-term Storage oads (category E) Water tank oad Medium-term Snow Uniformy distributed imposed oads on foors and baconies in categories A - D Imposed oads on garages and trafficabe areas (categories F and G) Actions due to moisture variation Short-term Imposed oads on stairs Concentrated imposed oad (Q k ) Horizonta oads on partition was and parapets Maintenance oad or oad caused by persons on a roof (category H) Vehice oads in category E Actions due to transport vehices Instaation oads Instantaneous Wind Accidenta action Service casses (1) The foowing sets out additiona information on the assignment of structures to service casses given in (2)P, (3)P and (4)P: Timber structures in heated rooms or in corresponding moisture conditions beong to service cass 1. Generay, any structures in therma insuation and beams with their tension side within therma insuation may aso be incuded in service cass 1. Service cass 2 incudes dry timber structures outdoors. Structures shoud be in a covered and ventiated space and we protected underneath and on the sides from getting wet. For instance, timber structures in a ground foor and cod attic space are usuay incuded in this service cass. Service cass 3 incudes timber structures exposed to weather, in a damp space outside or subject to the immediate effect of water. When assessing the durabiity of a timber structure, the service cass 3 is further divided into two different sub-casses describing the degree of exposure to moisture (see EN 335-1:2005). In addition to the average moisture content, attention shoud be paid to moisture variation in assignment of structures to service casses. The effect of moisture variation on a timber structure may be greater than the

3 3 effect of high average moisture eve. Particuar attention shoud be paid in service cass 1 to the risk of timber spitting Design vaue of materia property 2.4.1(1)P Vaues given in Tabe 2.3(FI) are used for strength and stiffness properties of materias. Tabe 2.3(FI) Partia factors γ M for materia properties and resistances Fundamenta combinations: Soid timber and round timber generay 1,4 Coniferous sawn timber in strength cass C35 1,25 Gued aminated timber, LVL 1,2 Wood-based panes 1,25 Connections * ) Punched meta pate fasteners: - anchorage strength 1,25 - pate (stee) strength 1,1 Accidenta combinations 1,0 * ) In the cacuation of the design resistance of a connection, the partia safety factor γ M of the timber materia is used. If two or more timber materias with different partia safety factors are connected together the highest γ M vaue is used for the connection. Aternativey, the atera oad-carrying capacity of meta dowe-type fasteners, F v,rd, may be cacuated directy with the design vaues of the materia properties. For the design vaues of embedment strength and axia withdrawa capacity, f h,d and F ax,rd, the partia and k mod factors of the actua timber materia are used in equation (2.14) of EN For the yied moment of stee fasteners the partia safety factor γ M = 1,1 is used, hence M y,rd = M y,rk /1,1. The resistances of stee members in a connection are verified according to Eurocode 3 with the partia safety factors of materia properties given in the Nationa Annex to EN Doube tapered, curved and pitched cambered beams 6.4.3(8) The tensie stresses perpendicuar to grain in doube tapered, curved and pitched cambered beams may be evauated using equation (6.55), if the timber has a surface treatment preventing the moisture transfer. Otherwise equation (6.54) is appied. 7.2 Limiting vaues for defections of beams 7.2(2) When defection of a structure or horizonta defection of a buiding is harmfu, the serviceabiity imits of deformations for the characteristic combinations of actions are according to tabe 7.2 uness due to the type of structure, purpose of use or nature of activity other vaues can be considered more appropriate. If the wind oad is not the eading variabe action (Q k1 ), it may be disregarded in the oading combinations of serviceabiity imit states.

4 4 Tabe Limiting vaues for defections. Defection of cantievers may be doube. is the span width and H is the height of the considered point in buiding. Structure w inst 1) w net,fin w fin 2) Main girders /400 /300 /200 Purins and other secondary girders - /200 /150 Horizonta defection of the buiding - H/300-1) Appied ony to foor members 2) Reates to precambered structures and curved or anged structures between supports Residentia foors 7.3.3(2) The foowing method is recommended for the vibration design of foors. This repaces cause of EN with fufiing a its criteria. Vibrations caused by waking are taken into account in the serviceabiity imit state design of foors in residentia, office and commercia buidings or of foors in other congregate areas. For foors of residentia or office areas with a fundamenta frequency ess than 9 Hz (f 1 < 9 Hz) a specia investigation shoud be made. For foors of residentia or office areas with a fundamenta frequency greater than 9 Hz (f 1 > 9 Hz) the foowing requirement shoud be satisfied, uness otherwise agreed with the cient: δ < 0,5 mm (7.3) where δ is the maximum instantaneous defection of foor beam caused by a vertica concentrated static force of 1 kn. For sma rooms, the aowed defection of 0,5 mm may be increased by a factor k presented in figure k Maximum side ength of room [m] Figure 7.2 The increasing factor k for the defection imit.

5 5 In the addition to defection of foor beam δ, the oca defection of skin pate or foating foor may be at maximum 0,5 mm due to the point oad of 1 kn. For simpy supported foor, the fundamenta frequency may be cacuated as f 1 π ( EI) = (7.4-FI) 2 2 m For two-way bearing foor, the fundamenta frequency may be cacuated as π f = ( EI ) ( ) EI b m b b ( EI ) where: (7.5-FI) is the foor span, in m; b is the width of room, in m; (EI) is the equivaent pate bending stiffness of the foor about an axis perpendicuar to the beam direction, in Nm 2 /m; (EI) b is the equivaent pate bending stiffness of the foor about an axis parae to the beam direction, in Nm 2 /m; m is the mass per unit area cacuated as the sum of the sef-weight of the foor and the quasi-permanent vaue of the imposed oad (ψ 2 q k ), in kg/m 2. The maximum defection caused by the point oad (F = 1 kn) may be cacuated for a simpy supported foor as 2 F 42 kδ ( EI) δ = min (7.6-FI) 3 F 48 s ( EI) where: k ( EI) b δ = 4 with the restriction: k δ < b/. (7.7) ( EI) s is the spacing of foor beams, in m. The expression (7.6-FI) may be used aso for the two-way bearing foor. In that case the restriction k δ < b/ needs not to be appied. These rues, as such, may aso be appied for continuous foor beams and sabs. However, in that case the foor structure shoud not be continuous between different apartments.

6 Naied timber-to-timber connections (4) NOTE 2 The rues of cause (4) are used to determinate the atera oad-carrying capacity of nais in end grain (7) The rues of cause (7) are not appied to naied joints Genera (7) The simpified anaysis of wa diaphragms is carried out using method A in accordance with cause of EN Bracing of beam and truss systems (1) Vaues given in Tabe 9.2(FI) are used for modification factors in design of bracing. Tabe 9.2(FI) Vaues of modification factors. Modification factor Vaue k s o 180 * ) 2 + 2cos m k f,1 50 k f,2 80 k f,3 50 * ) m is the number of bays each of ength a; m > 2 (see Figure 9.9 of EN ) Erection (3) The maximum bow permitted after instaation in bay of any truss member is a bow,perm = 15 mm. The maximum bow permitted in tota ength of chord a bow,perm = min(l/300; 50 mm), when L is the ength of chord (4) The maximum permitted deviation of a truss from true vertica aignment a dev,perm = min(10 mm + H /200; 25 mm), when H is the height of the truss in the actua point, in mm.

7 7 Annex A Bock shear and pug shear faiure at mutipe dowe-type stee-to-timber connections Informative Annex A of EN is appied in Finand for stee-to-timber connections in tension as normative with the foowing additions. In conjunction with LVL equation (A.1) of EN is repaced by 1,25Anet,t f t,0,k F bs,rk = max 0, 7Anet,v f v,0,fat,k where: f v,0,fat,k is the characteristic fatwise shear strength of LVL. Bock shear capacity sha be verified aso for tension stressed two and mutipe shear timber-to-timber joints. For timber-to-timber joints equation (A.3) of EN simpifies to form A net,v = L net,v t 1. Appendix B Mechanicay jointed beams Informative Annex B may be used. Appendix C Buit-up coumns Informative Annex C may be used.