Characteristics of Duobalken®/Triobalken® laminated beams according to EN 14080 for selected strength classes
Strength class | C18 | C24 | C30 | |
---|---|---|---|---|
Strength values in N/mm² | ||||
Characteristic bending strength | fm,ka) | 18 | 24 | 30 |
Characteristic strength parallel to grain | ft,0,k a) | 11 | 14 | 18 |
Characteristic tension strength perpendicular to grain | ft,90,k | 0,4 | 0,4 | 0,4 |
Characteristic compression strength parallel to grain | fc,0,k | 18 | 21 | 23 |
Characteristic compression strength perpendicular to grain | fc,90,k | 2,2 | 2,5 | 2,7 |
Characteristic shear and torsional shear strength | fv,kb) | 3,4 | 4,0 | 4,0 |
Coefficient kcr | fc,90,k | 2,0/fv,k | 2,0/fv,k | 2,0/fv,k |
Stiffness values in N/mm² | ||||
Mean value of modulus of elasticity parallel to grain | E0,meanb) | 9.000 | 11.000 | 12 000 |
Characteristic value of modulus of elasticity parallel to grain | E0,05 | 6.000 | 7.400 | 8.000 |
Mean value of modulus of elasticity perpendicular to grain | E90,mean | 300 | 370 | 400 |
Mean value of Shear modulus | Gmeanb)c) | 560 | 690 | 750 |
Density values in kg/m² | ||||
Characteristic value of density | Pk | 320 | 350 | 380 |
Mean value of density | Pmean | 380 | 420 | 460 |
a) For structural timber with rectangular cross-section and density of pk < 700 kg/m³, the characteristic strength value can be multiplied by the coefficient
kh=min.{(150/h)0.2/1.3}
when bending cross-section heights and applying traction of h<150 mm to cross-section widths; see EN 1995-1-1: 2010-12, 3.2 (3).
Cross-section width is the largest cross-sectional dimension for components under tensile stress, see DIN EN 1995-1-1/NA 2013-08, NCI to 3.2 (3).
b) The characteristic rolling shear strength fR,k can be assumed to be 1.0 N/mm² for all strength classes. The shear modulus for the rolling shear strain can be assumed to be GR,mean = 0.10 Gmean.
c) G05 = 2/3 Gmean applies, see also DIN EN 1995-1-1/NA, NCI to 3.2 (NA.7).
d) No mean density values are given in DIN 1052:2008. The values shown here were therefore taken from DIN EN 338:2010-02.
Characteristics of Duobalken®/Triobalken® according to Z 9.1-440 National technical Approval for selected strength classes
Strength class | C18 | C24 | C30 | |
---|---|---|---|---|
Strength values in N/mm² | ||||
Characteristic bending strength | fm,ka) | 18 | 24 | 30 |
Characteristic tension strength parallel to grain | ft,0,k a) | 11 | 14 | 18 |
Characteristic tension strength perpendicular to grain | ft,90,k | 0.4 | 0.4 | 0.4 |
Characteristic compression strength parallel to grain | fc,0,k | 18 | 21 | 23 |
Characteristic compession strength perpendicular to grain | fc,90,k | 2.2 | 2.5 | 2.7 |
Characteristic shear and torsional shear strength | fv,kb) | 2.0 | 2.0 | 2.0 |
Coefficient kcr | fc,90,k | 2.0/fv,k | 2.0/fv,k | 2.0/fv,k |
Stiffness values in N/mm² | ||||
Characteristic value of modulus of elasticity parallel to grain | E0,meanb) | 9,000 | 11,600 | 12,000 |
Mean value of modulus of elasticity perpendicular to grain | E0.05 | 6,000 | 7,400 | 8,000 |
Mean value of modulus of elasticity perpendicular to grain | E90,mean | 300 | 370 | 400 |
Mean value of Shear modulus | Gmeanb)c) | 560 | 690 | 750 |
Density values in kg/m² | ||||
Characteristic value of Density | Pk | 320 | 350 | 380 |
Mean value of density | Pmeand) | 380 | 420 | 460 |