Evo Design  structural
engineering

Calculation
No.



001WOOD BEAM


CALCULATION SHEET

Project No.










onlinestructuraldesign.com

SAMPLE CALCULATION


Project
Title:

Wood beam interactive design spreadsheet


Calc. By

Date

Rev.











MN

16.04.2014

0


Subject

Wood Element Bending Capacity (EC5)


Checked By

Date












CN

16.04.2014
















Input

Output







Element section and dimensions

Element verification







Material








Loads





















Wood Element
Bending Moment Capacity Calculation


per EN
199511:2004* & EN 338*


Maximum working
loads (Ultimate Limit State)








M_{y,Ed}=


kN*m

bending moment yy








M_{z,Ed}=


kN*m

bending moment zz





















Element dimensions
 Rectangular cross section








h =

20

cm

height










d =

10

cm

width











(parameters that can not be modified in the demo
version)







Section Properties








A =

d*h =


cm^{2}

section area





I_{Y} =

d*h^{3}/12 =


cm^{4}

moment of inertia about yy axis





I_{z} =

d^{3}*h/12 =


cm^{4}

moment of inertia about zz axis














Material
characteristics






per EN 33897  Table 1


Wood strength
class:












f_{m,k} =


N/mm^{2}






Characteristic
bending strength


g_{m} =








per EN 199511  Table 2.3










1.3 for
solid timber, 1.25 for glued laminated timber


k_{h} =

min( (150/h)^{0.2} ; 1.3) =





per EN
199511  Section 3.2 (3), formula (3.1)









for timber
with density less than 700 kg/m^{3} and










h < 150mm
the characteristic valus of f_{m,k} andÂ










f_{t,0,k} may be increased
by the factor k_{h}


k_{mod} =








per EN 199511  Table 3.1










Load duration
classes per EN 199511










Section 2.3.1.2  Table 2.1 and 2.2










Service classes per EN 199511  Section 2.3.1.3















f_{m.y.d} =

f_{m.y.d} =

k_{mod} *k_{h} * f_{m,k}

/ g_{m} =


N/mm^{2}


design
bending strength about y and z axis










per EN
199511  Section 2.4.1, formula (2.14)


s_{m.y.d} =

M_{y,Ed} * (h/2) / I_{y} =


N/mm^{2}




Design
bending stress about the principal y axis


s_{m.z.d} =

M_{z,Ed} * (d/2) / I_{z} =


N/mm^{2}




Design
bending stress about the principal z axis















k_{m} =

0.7

for rectangular sections




per EN
199511  Section 6.1.6 (2)















Check
on for yy axis












( s_{m.y.d} / f_{m.y.d} ) + k_{m} * ( s_{m.z.d} / f_{m.z.d} ) =





per EN
199511  Section 6.1.6, formula (6.11)













Check
on for zz axis












k_{m} * ( s_{m.y.d} / f_{m.y.d} ) + ( s_{m.z.d} / f_{m.z.d} ) =





per EN
199511  Section 6.1.6, formula (6.12)













References:


EN 199511:2004  Eurocode 5: Design of timber structures 
Part 11: Common rules and rules for buildings


EN 338 : 2003  Structural Timber; Strength Classes


