9. CALCULATION EXAMPLES OF LVL STRUCTURES
ULS design
Bending moment resistance
M_d = E_(d,ULS)∙s∙L^2/8 = 4,03kN/m^2∙0,4m∙〖(4,5m)〗^2/8 = 4,
σ_(m,d)=M_d/W=(4,1 kNm)/(4,32〖∙10〗^5 mm^3 )=9,5 N/mm^2
f_(m,0,edge,d)=k_mod/γ_M ∙k_h∙f_(m,0,edge,k)
(4.3)
f_(m,0,edge,d)=0,8/1,2∙1,034∙44 N/mm^2 =30,3 N/mm^2
σ_(m,d)≤f_(m,0,edge,d) →OK
Lateral torsional buckling is prevented by the fixing of the decking.
Shear resistance
V_d = E_(d,ULS)∙s∙L/2 = 4,03kN/m^2∙0,4m∙4,5m/2 = 3,6 kN
τ_(v,d)=〖3∙V〗_d/(2∙A)=(3∙3,6 kN)/(2 ∙10 800mm^2 )=0,5 N/mm^2
f_(v,0,edge,d)=k_mod/γ_M ∙f_(v,0,edge,k)=0,8/1,2∙4,2 N/mm^2 =2,8 N/mm^2
τ_(m,d)≤f_(v,0,edge,d) →OK
Compression perpendicular to the grain
F_(c,90,d) = V_d = 3,6 kN
σ_(c,90,d)=F_(c,90,d)/A_ef =F_(c,90,d)/(b∙(l_s
(4.14)
σ_(c,90,d)=3,6kN/(45 mm∙(45 mm+15mm
k_(c,90)∙f_(c,90,edge,d)=k_(c,90)∙k_mod/γ_M ∙
(4.13)
k_(c,90)∙f_(c,90,edge,d)=1,0∙0,8/1,2∙6 N/mm^2=4
(
k
c,90
Table 4.7)
σ_(c,90,d)≤k_(c,90)∙f_(m,0,edge,d) →OK
SLS design
Instantaneous deflection
w_inst = w_(inst,g) + w_(inst,q)
w_(inst,g)=(5〖∙g〗_(d,SLS)∙
(4.74)
d,SLS
G 1,k 2,k
G k
(4.1)
d,SLS
= 1,0 ∙ (0,6 kN/m
2
+ 0,3 kN/m
2
) + 1,0 ∙ 2,0 kN/m
2
d,SLS
= 2,9 kN/m
2
d
=
d,ULS
∙ ∙
2
/8 = 4,03kN/m
2
∙ 0,4 ∙ (4,5m)
2
/8 = 4,1 kNm
m,d
=
d
= 4,1 kNm 4,32 ∙ 10
5
mm
3
= 9,5 N/mm
2
m,0,edge,d
=
mod M
∙
h
∙
m,0,edge,k
(4.3)
m,0,edge,d
= 0,8 1,2 ∙ 1,034 ∙ 44 Nmm
2
= 30,3 N/mm
2
m,d
≤
m,0,edge,d
→ OK
d
=
d,ULS
∙ ∙ /2 = 4,03kN/m
2
∙ 0,4m ∙ 4,5m/2 = 3,6 kN
d,SLS
=
G
∙ (
1,k
+
2,k
) +
G
∙
k
(4.1)
d,SLS
= 1,0 ∙ (0,6 kN/m
2
+ 0,3 kN/m
2
) + 1,0 ∙ 2,0 kN/m
2
d,SLS
= 2,9 kN/m
2
d
=
d,ULS
∙ ∙
2
/8 = 4,03kN/m
2
∙ 0,4m ∙ (4,5m)
2
/8 = 4,1 kNm
m,d
=
d
= 4,1 kNm 4,32 ∙ 10
5
mm
3
= 9,5 N/mm
2
m,0,edge,d
=
mod M
∙
h
∙
m,0,edge,k
(4.3)
m,0,edge,d
= 0,8 1,2 ∙ 1,034 ∙ 44 Nmm
2
= 30,3 N/mm
2
m,d
≤
m,0,edge,d
→ OK
d
=
d,ULS
∙ ∙ /2 = 4,03kN/m
2
∙ 0,4m ∙ 4,5m/2 = 3,6 kN
v,d
= 3 ∙
d
2 ∙
= 3 ∙ 3,6 kN
2 ∙ 10 800mm
2
= 0,5 N/mm
2
v,0,edge,d
=
mod M
∙
v,0,edge,k
= 0,8 1,2 ∙ 4,2 Nmm
2
= 2,8 N/mm
2
m,d
≤
v,0,edge,d
→ OK
c,90,d
=
d
= 3,6 kN
c,90,d
=
c,90,d ef
=
c,90,d
∙�
support
+15 mm�
(4.14)
c,90,d
=
3,6kN
45 mm ∙ (45 mm + 15mm) = 1,35 N/mm
2
c,90
∙
c,90,edge,d
=
c,90
∙
mod M
∙
c,90,edge,k
(4.13)
c,90
∙
c,90,edge,d
= 1,0 ∙
0,8 1,2
∙ 6 N/mm
2
= 4N/mm
2
(
k
c,90
Table 4.7)
c,90,d
≤
c,90
∙
m,0,edge,d
→ OK
inst
=
inst,g
+
inst,q
inst,g
=
5∙
d,SLS
∙ ∙
4
384∙
mean
∙
+
6 5
∙
d,SLS
∙ ∙
2
8∙
mean
(4.74)
inst,g
= 2,69 mm + 0,17 mm = 2,86 mm
inst,q
= 5 ∙
d,SLS
∙ ∙
4
384 ∙
mean
∙ + 6/5 ∙
d,SLS
∙ ∙
2
8 ∙
mean
= 5,97 mm + 0,38 mm = 6,35 mm
d
2 ∙
k 1 0
0,5 N/mm
0
d
∙
0 e k
,
2
d
0 e ,d
O
=
d e
c
∙
t
=
,9
∙
9 e k
c,9
∙
9 e d
0,8 1,2
N
g
3 4
6 5
∙
m
6
∙ 8
+
d S S
= 5,97 mm + 0,38 mm = 6,35 mm
v,d
= 3 ∙
d
2 ∙
= 3 ∙ 3,6 kN
2 ∙ 10 800mm
2
= 0,5 N/mm
2
v,0,edge,d
=
mod M
∙
v,0,edge,k
= 0,8 1,2 ∙ 4,2 Nmm
2
= 2,8 N/mm
2
m,d
≤
v,0,edge,d
→ OK
c,90,d
=
d
= 3,6 kN
c,90,d
=
c,90,d ef
=
c,90,d
∙�
support
+15 mm�
(4.14)
c,90,d
=
3,6kN
45 mm ∙ (45 mm + 15mm) = 1,35 N/mm
2
c,90
∙
c,90,edge,d
=
c,90
∙
mod M
∙
c,90,edge,k
(4.13)
c,90
∙
c,90,edge,d
= 1,0 ∙
0,8 1,2
∙ 6 N/mm
2
= 4N/mm
2
(
k
c,90
Table 4.7)
c,90,d
≤
c,90
∙
m,0,edge,d
→ OK
inst
=
inst,g
+
inst,q
inst,g
=
5∙
d,SLS
∙ ∙
4
384∙
mean
∙
+
6 5
∙
d,SLS
∙ ∙
2
8∙
mean
(4.74)
inst,g
= 2,69 mm + 0,17 mm = 2,86 mm
inst,q
= 5 ∙
d,SLS
∙ ∙
4
384 ∙
mean
∙ + 6/5 ∙
d,SLS
∙ ∙
2
8 ∙
mean
= 5,97 mm + 0,38 mm = 6,35 mm
216 (255)
0,edge,d
= 0,8 1,2 ∙ 1,034 ∙ 44 Nmm
2
= 30,3 N/mm
2
m,d
≤
m,0,edge,d
→ OK
Lateral torsional buckling is prevented by the fixing of the decking.
hear resistance
d
d,ULS
∙ ∙ /2 = 4,03kN/m
2
∙ 0,4m ∙ 4,5m/2 = 3,6 kN
v,d
= 3 ∙
d
2 ∙
= 3 ∙ 3,6 kN
2 10 800mm
2
= 0,5 N/mm
2
v,0,edge,d
=
mod M
∙
v,0,edge,k
= 0,8 1,2 ∙ 4,2 Nmm
2
= 2,8 N/mm
2
m,d
≤
v,0,edge,d
→ OK
ompression perpen icular to the grain
,
,d
=
d
= 3,6 kN
c,90,d
=
c,90,d ef
=
c,90,d
∙�
support
+15 mm�
(4.14)
c,90,d
=
3,6kN
45 mm ∙ (45 mm + 15mm) = 1,35 N/mm
2
c,90
∙
c,90,edge,d c,90
∙
mod M
∙
c,90,edge,k
(4.13)
,
∙
c,90,edge,d
= 1,0 ∙
0,8 1,2
∙ 6 N/mm
2
= 4N/mm
2
(
k
c,90
Table 4.7)
c,90,d
≤
c,90
∙
m,0,edge,d
→ OK
LS design
nstantaneous deflection
inst
=
inst,g
+
inst,q
i ,g
5 ∙
d,SLS
∙ ∙
4
384 ∙
mean
∙ + 6/5 ∙
d,SLS
∙ ∙
2
8 ∙
mean
= 2,69 mm + 0,17 mm = 2,86 mm
(4.74)
d,SLS
4
d,SLS
2
180
LVL Handbook Europe




