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Strength, stiffness and density characteristics

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