Timber cross calculation taking into account bending moments, shear and axial forces.
General options:
Option
Unit
Description
Section
-
Name of cross section or section group is supported by EN 1995-1-1 and related national annexes such as NEN-EN 1995-1-1. Items listed in the Sections Definition dialog window depend on the chosen code or/and national annex
Material
-
Strength classes: characteristic values for softwoods
C14
C16
C18
C20
C22
C24
C27
C30
C35
C40
C45
C50
Strength properties [N/mm²]
Bending
fm;0;k
14
16
18
20
22
24
27
30
35
40
45
50
Tension parallel
ft;0;k
8
10
11
12
13
14
16
18
21
24
27
30
Tension perpendicular
ft;90;k
0.4
0.5
0.5
0.5
0.5
0.5
0.6
0.6
0.6
0.6
0.6
0.6
Compression parallel
fc;0;k
16
17
18
19
20
21
22
23
25
26
27
29
Compression perpendicular
ft;90;k
2.0
2.2
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.1
3.2
Shear
fv;0;k
1.7
1.8
2.0
2.2
2.4
2.5
2.8
3.0
3.4
3.8
3.8
3.8
Stiffness properties [kN/mm²]
Mean E parallel
E0;mean
7
8
9
9.5
10
11
11.5
12
13
14
15
16
5% E parallel
E0;0.05
4.7
5.4
6.0
6.4
6.7
7.4
7.7
8.0
8.7
9.4
10.0
10.7
Mean E perpendicular
E90;mean
0.23
0.27
0.30
0.32
0.33
0.37
0.38
0.40
0.43
0.47
0.50
0.53
Mean G
Emean
0.44
0.50
0.56
0.59
0.63
0.69
0.72
0.75
0.81
0.88
0.91
1.00
Density [kg/m³]
Density
ρk
290
310
320
330
340
350
370
380
400
420
440
460
Mean density
ρmean
350
370
380
390
410
420
450
460
480
500
520
550
These properties relate to timber at a temaperature 20°C and a relative humidity of 65%.
D30
D35
D40
D50
D60
D70
Strength properties [N/mm²]
Bending
fm;0;k
30
35
40
50
60
70
Tension parallel
ft;0;k
18
21
24
30
36
42
Tension perpendicular
ft;90;k
0.6
0.6
0.6
0.6
0.6
0.6
Compression parallel
fc;0;k
23
25
26
26
32
34
Compression perpendicular
ft;90;k
8.0
8.4
8.8
9.7
10.5
13.5
Shear
fv;0;k
3.0
3.4
3.8
4.6
5.3
6.0
Stiffness properties [kN/mm²]
Mean E parallel
E0;mean
10
10
11
14
17
20
5% E parallel
E0;0.05
8.0
8.7
9.4
11.8
14.3
16.8
Mean E perpendicular
E90;mean
0.64
0.69
0.75
0.93
1.13
1.33
Mean G
Emean
0.60
0.65
0.70
0.88
1.06
1.25
Density [kg/m³]
Density
ρk
530
560
590
650
700
900
Mean density
ρmean
640
670
700
780
840
1080
These properties relate to timber at a temaperature 20°C and a relative humidity of 65%.
Load duration class
-
Approximate duration
Examples of loading
Permanent
More than 10 years
Self-weight
Long-term
6 months to 10 years
Storage loading, water tanks
Medium-term
1 week to 6 months
Imposed floor load
Short-term
Less than 1 week
Snow, maintenance loading on roofs, residual structure after accidental event
Instantaneous
Wind, impact loading, explosion
Load service class
-
Service class
Definition
Examples
1
Temperature of 20°C, relative humidity of surrounding air only exceeding 65% for a few weeks per year. Moisture content of timber generally not more than 16%
Warm roofs, intermediate floors, internal and party walls
2
Temperature of 20°C, relative humidity of surrounding air only exceeding 85% for a few weeks per year. Moisture content of timber generally not more than 20%
Cold roofs, ground floors, external walls and external uses where timber is protected from direct wetting
3
Conditions leading to higher moisture contents than in service class 2
External uses, fully exposed
Forces:
Parameter
Unit
Description
Nc;Ed
kN
Compression axial force
Nt;Ed
kN
Tension axial force
Vy;Ed
kN
Shear force along local y’-y’ axis
Vz;Ed
kN
Shear force along local z’-z’ axis
Mx;Ed
kNm
Bending moment on the x-axis
My;Ed
kNm
Bending moment on the y-axis
Mz;Ed
kNm
Bending moment on the z-axis (only for rectangular cross section)
