Example description....
Actions....
Timber Properties....
Bending....
Deflections....
Vibration....
Lateral Buckling....
Shear....
Bearing....

Example Description To Design the timber floor joists for a domestic dwelling using timber of strength clss C16 based on the following data
Floor width , b = 3,6m and floor span L is 3,4m
Specific permanent action, g Specific variable action, q Design Load on the joists is F
Assuming that the average moisture content of the timber joists does not exceed 20 per cent during the life of the
structure, design the joists for service class 2. Service Class As the (assumed) beam is in bending and is over 150mm depth a value of k If members are not to fail in bending, the following conditions should be satisfied: It is clear from
Note simple equation used in this section are obtained from the following pages Instantaneous deflection due to permanent actions u F The instantaneos deflection due to permanent actions u u
The instantaneous deflection due to variable actions u F
u
u u Assuming that f1 > 8 Hz it is necessary to check that W/F ≤ a and ν b k Hence k Hence k Therefore the maximum deflection caused by a concentrated static force F = 1,0, w, is Check impulse velocity Floor width, b = 3.4 m and floor span, l = 3.6 m.
I Mass due to permanent actions per unit area, m, is m = permanent action / gravitational constant The fundamental frequency of vibration, f The number of first order modes n The unit input velocity is Assume the damping coefficient ξ = 0,002 form since a ( = 0,82mm) < 1 is given by b = 180 -60.a = 180 - 60 . 0,82 = 131 Hence Permissible floor velocity = It is not necessary to check for lateral buckling because the beams are all supported along their length by the upper tongue and groove boards. Reference... Shear The design shear strength is The maximum shear force is Design shear stress at the neutral axis is
reference Compression The bearing design force is F The design bearing stress Assuming that the floor joists are supported on 100m wide wallls as shown above the bearing stress resulting is calculated by The design bearing strength The design compressive strength perpendiculr to the grain f a = 0 , L |

- Introduction to Structural Timber design to The Eurocodes..Very important document to latest codes :75 page document
- Strength Graded Timber Mark..Download showing identification to be shown on strength graded timber
- Wood Handbook -- Wood as an Engineering Material..Downloads ..Comprehensive Document (American ) Excellent
- Canadian Wood Council ..Excellent site on Wood Engineering - my words
- Timber Trade Federation ..The Timber Trade Federation is the official voice of the UK timber trade.
- Scottish Timber Trade Association..Home page with links to useful information pages.
- In situ strength grade..Notes on visual strength grading of timber
- BSW Timber..Large UK Sawmill homepage