E
Emean, fin , mean. EC5, equation 2.7 2.34 Gmean,fin mean , EC5, equation 2.8 2.35 ser.fin , EC5, equation 2.9 2.36 where Emean fin is the final mean value of the modulus of elasticity, Emean is the mean value of elasticity, Gmean,fin is the final mean value of the shear modulus, Gmean is the mean value of the shear modulus, K ,fin is the final slip modulus, Kser is the slip modulus, defined in EC5, 7.1, and kdef is the deformation factor for timber and wood-based products and, for connections,...
Info Wnn 1
b Edge and end distances Fig. 10.11. Fastener spacings and distances. to allow fixings to be formed in dense timber and this is a requirement for nails driven in timber with a characteristic density greater than 500 kg m3 EC5,8.3.1.1 and for all screws in hardwood EC5,10.4.5 . The above and other related requirements in EC5 are summarised in the notes accompanying Tables 10.8 and 10.9. EC5 rules for spacing, edge and end distances for joints formed with nails and or staples are summarised in...
Info Tpc
Relative slenderness about the krel.z equation 5.3 EC5, equation 6.22 As both relative slenderness ratios are greater than 0.3, conditions in 5.3.1 b apply EC5, 6.3.2 3 Redistribution factor for a km 0.7 Factor pc for solid timber pc 0.2 Factor, ky equation 5.5a EC5, equation 6.27 equation 5.4a EC5, equation 6.25 Factor, kz equation 5.5b EC5, equation 6.28 Instability factor about the z-z axis equation 5.4b EC5, equation 6.26 kz 0.5 1 pc krel.z - 0.3 keU
Sls Tjj
Depending on the connector type, the toothed plate will be made from cold rolled uncoated low-carbon steel, continuous hot dipped galvanised mild steel or malleable cast iron. With steel connectors, the edges of the connector plate are bent over to form triangular projecting teeth, and with cast iron connectors, conical spikes having a blunted point project from one or both faces. An example of a circular toothed-plate connector formed from steel plate having projecting teeth on one or both...
Axial Loading Of Metal Dowel Connection Systems
The strength equations given in the following sub-sections assume that the tensile strength of fasteners will always exceed their withdrawal capacity from the connection. If, however, there is a need to evaluate the tensile strength of the fastener, it should be carried out in accordance with the requirements of EN 1993-1-1. The withdrawal capacity of nails loaded axially is dependent on the type of nail being used. Smooth round wire nails give the poorest result and with threaded nails the...
fhk
In deriving these equations, friction forces between the members of the connection are ignored as well as the withdrawal resistance of the fasteners. In EC5 the Johansen yield equations form the basis of the strength equations, however for those failure modes that involve yielding of the fastener, the equations have been modified to include for friction and withdrawal effects. There are two types of friction effects that can arise in a connection. One will develop if the members are in contact...
N I
Medium duration variable loading acting downwards on the beam, Qk.1 Instantaneous duration variable loading acting upwards on the beam, Qk.2 Table 2.2, f values UKNA to EN 1990 2002 TableNA.Al.1 Factor for the combination value of medium duration f01 0.7 Factor for the combination value of wind action Qk 2, f0 2 f0 2 0.5 a Partial factors for equilibrium ULS Table 2.8, equation EQU a UKNA to EN 1990 2002 TableNA.A1.2 A For permanent favourable actions, yG.e yG.e 0.9 For variable unfavourable...
Examples Yxk
As stated in 4.3, in order to verify the ultimate and serviceability limit states, each design effect has to be checked and for each effect the largest value caused by the relevant combination of actions must be used. However, to ensure attention is primarily focussed on the EC5 design rules for the timber or wood product being used, only the design load case producing the largest design effect has generally been given or evaluated in the following examples. Example 10.13.1 A timber-to-timber...
I Dgu
Fig. 8.7. Shear force distribution and loads on packs and gussets based on Figure C.2 in EC5 . a c,0,d is the direct stress on the column, i.e
Info Des
Note i is the beam span or the length of the cantilever. Note i is the beam span or the length of the cantilever. wcreep is the creep deformation i.e. the deformation that is permitted to arise with time under the combination of loading causing the creep behaviour. wfin is the final deformation i.e. the combination of the instantaneous and the creep deformation. wnet,fin is the net final deformation i.e. the deformation below the straight line joining the supports. The net final deformation can...
F Pfg
and F90 Rk for softwood is defined below. Fv Ed1 and Fv Ed 2 are the design shear forces on each side of the connection as shown in Figure 10.13. Timber trusses are normally fabricated using softwood species and based on a linear elastic fracture mechanics approach the characteristic splitting capacity of softwood member s A, shown in Figure 10.13, will be where w max wpl 100 a35, 1 for punched metal plate fasteners and w 1 for all other fasteners, F90jRk is the characteristic splitting...
Info Twe 1
Design bending strength taking lateral torsional buckling effect into account, equation 4.13 EC5, equation 6.33 fmr.y.d 19.01 N mm2 Bending strength of a glulam beam greater than the bending stress and is satisfactory for this loading condition of the beam plus the Vd 33.62 kN Tv_d 0.78 N mm2 The design load case will be due to a combination of self-weight of the beam plus the permanent and variable loading Design value of the end reaction, Reacd Design bearing stress, ac 90 d equation 4.22...
Table 8.6 In Ec5
In the draft proposal, the content of Table 8.6 in EC5 is to be altered and the minimum end and edge distances are to be based on the distance to the centre of gravity of the threaded part of the screw in the relevant member. Providing the timber thickness is gt 12 d, where d is the screw diameter, for joints formed as indicated in Figure C2, the minimum spacings, edge and end distances are to be as follows Minimum screw spacing in a plane parallel to the grain, a1 5d. Minimum screw spacing...
References Xoo
1 BS EN 1995-1-1 2004. Eurocode 5 Design of Timber Structures. Part 1-1 General - Common Rules and Rules for Buildings, British Standard Institution. 2 Timoshenko, S.P., Gere, J.M. Theory of Elastic Stability. International Student Edition, 2nd edn. McGraw-Hill Book Company, New York, 1961. 3 NAtoBSEN 1995-1-1 2004. UK National Annex to Eurocode 5 Designof Timber Structures. Part 1-1 General - Common Rules and Rules for Buildings, British Standards Institution. 4 Br ninghoff, H., Bracing -...
References Jjk
1 BS EN 1995-1-1 2004. Eurocode 5 Design of Timber Structures. Part 1-1 General - Common Rules and Rules for Buildings, British Standards Institution. 2 BS EN 386 2001. Glued Laminated Timber - Performance Requirements and Minimum Production Requirements, British Standards Institution. 3 BS EN 1194 1999. Timber Structures-Glued Laminated Timber-Strength Classes and Determination of Characteristic Values, British Standards Institution. 4 BS EN 338 2003. Structural Timber - Strength Classes,...
The Inplane Racking Resistance Of Timber Walls Under Horizontal And Vertical
The stud walls associated with timber-framed buildings are usually sheathed on one or both faces with the sheathing securely fixed to the studs, enabling the wall to act as a rigid diaphragm. The fixings e.g. nails provide the bulk of the racking resistance through timber bearing and nail deformation when the lateral external force is applied as shown in Figure 9.8b. Horizontal sliding of the wall is resisted by anchorages such as nails or bolts along the sole plate sufficient to resist the...
L Psa
Table 1.3, strength class C16 BS EN 338 2003 E , Table 1 Characteristic compression strength fc 0 k 17 mm2 Characteristic compressive strength perpendicular to the grain, fc.90.k Fifth-percentile modulus of elasticity parallel to the grain, E005 fc.90.k 2.2 N mm2 E005 5.4 kN mm2 Table 2.8 UKNA to BS EN 1990 2002, Table NA.A1.2 B for the ULS Material factor for solid timber, ym Characteristic permanent compressive action, Gk Characteristic long-term compressive variable action, Qk Design...
Ei Rcu
Fig. 12.13. Member with rotational springs at each end. can be shown from basic principles that the member stiffness will equal 4EI L. To align with the member stiffness definition, the spring rotational stiffness at each end is written in a similar format as follows where k1 M1 ftr1 and k2 M2 ftr2, and M1 and M2 are the end moments on the beam, r1 and r2 are the rotations of the spring at end a and b, respectively, ja and jb are the secant rotational stiffness coefficients of the joint...
Member Span
In EC5 the bearing stress at the end of a beam is taken to be uniformly distributed over the bearing area, and for simply supported beams where the bearing area is much greater than is required for strength reasons, the beam need only be designed to span onto sufficient area to ensure that the design bearing strength is not exceeded. In such instances the design span, i.e. the effective span of the beam, will be the clear span plus half the bearing length at each end, as shown in Figure 4.2....
Minimum bolt spacing Using the data in Table
2 2 t2 h - 3 d 1mm Design shear stress is less than the shear design strength therefore OK. max 7 d, 80 mm 84 mm 90 mm , provided,
Floor And Roof Diaphragms
The design procedure given in EC5 for floor and roof diaphragms is a simplified approach to the design of such structures and applies only to diaphragms assembled from wood-based panels fixed to a timber-framed structure by mechanical fasteners, e.g. nails or screws. In deriving the lateral strength of the mechanical fixings at the edges of the panels, EC5, 9.2.3.1 2 , allows the capacity to be increased by 20 over the value calculated in accordance with the procedures described in Chapter 10....
A Lpl
Buckling resistance condition 5.3.1 EC5, 6.3.2 Relative slenderness about the Xrel y Xrel y 1.81 equation 5.3 EC5, equation 6.21