Es wird die gleiche Geometrie verwendet.
Für den Druckflansch muss ein b/t-Nachweis geführt werden.
Grenz b/t
b
t
<
12
,
9
b
t
=
0
,
53
−
0,009
2
⋅
0,017
{\displaystyle {\frac {b}{t}}<12{,}9{\frac {b}{t}}={\frac {0{,}53-0{,}009}{2\cdot 0{,}017}}}
15
,
32
≮
12
,
9
{\displaystyle 15{,}32\not <12{,}9}
Beulnachweis erforderlich
kσ= 0,43
λ
¯
p
=
b
f
/
2
−
t
w
/
2
t
f
2
⋅
28,121
76
⋅
ϵ
⋅
k
σ
{\displaystyle {\overline {\lambda }}_{p}={\frac {b_{f}/2-t_{w}/2}{t_{f2}\cdot 28{,}12176\cdot \epsilon \cdot {\sqrt {k_{\sigma }}}}}}
(Hergeleitete Formel 1)
λ
¯
p
=
0
,
53
/
2
−
0,004
5
0,017
⋅
28,121
76
⋅
ϵ
⋅
0
,
43
{\displaystyle {\overline {\lambda }}_{p}={\frac {0{,}53/2-0{,}0045}{0{,}017\cdot 28{,}12176\cdot \epsilon \cdot {\sqrt {0{,}43}}}}}
λ
¯
p
=
0,831
{\displaystyle {\overline {\lambda }}_{p}=0{,}831}
κ
p
=
1
λ
¯
p
2
−
0
,
51
=
1
0,831
2
−
0
,
51
{\displaystyle \kappa _{p}={\frac {1}{{\overline {\lambda }}_{p^{2}}-0{,}51}}={\frac {1}{0{,}831^{2}-0{,}51}}}
(DIN 18800-3 Tabelle 1)
κp = 0,83998
bf := bf ∙ κp = 0,53∙0,83998
bf := 0,4452
Mit der verkürzten Länge des Druckflansches wird gerechnet. Der Druckflansch in der DIN ist kürzer als im Eurocode.
As = bf2 ∙tf2 + hw ∙tw + bf1 ∙tf1
As = 0,37∙0,011 + 0,009∙2,9 + 0,4452∙0,017
As = 0,03774m²
Der Schwerpunkt hs wird vom unteren Stegende aus nach oben gemessen.
h
s
=
b
f
2
⋅
t
f
2
⋅
(
h
w
+
0
,
5
⋅
t
f
2
)
+
0
,
5
⋅
h
w
2
⋅
t
w
−
0
,
5
⋅
b
f
1
⋅
t
f
1
2
A
{\displaystyle h_{s}={\frac {b_{f2}\cdot t_{f2}\cdot (h_{w}+0{,}5\cdot t_{f2})+0{,}5\cdot h_{w}^{2}\cdot t_{w}-0{,}5\cdot b_{f1}\cdot t_{f1}^{2}}{A}}}
h
s
=
0
,
37
⋅
0,011
⋅
(
2
,
9
+
0
,
5
⋅
0,011
)
+
0
,
5
⋅
2
,
9
2
⋅
0,009
−
0,445
2
⋅
0,017
2
/
2
0,037
74
{\displaystyle h_{s}={\frac {0{,}37\cdot 0{,}011\cdot (2{,}9+0{,}5\cdot 0{,}011)+0{,}5\cdot 2{,}9^{2}\cdot 0{,}009-0{,}4452\cdot 0{,}017^{2}/2}{0{,}03774}}}
h
s
=
0,011
83
+
0,037
8
−
6
,
43
⋅
10
−
5
0,037
74
{\displaystyle h_{s}={\frac {0{,}01183+0{,}0378-6{,}43\cdot 10^{-5}}{0{,}03774}}}
hs =1,3145m
Das Flächenträgheitsmoment I besteht aus 3 Steineranteilen und 3 Eigenanteilen
I
=
∑
(
3
E
i
g
e
n
b
f
1
⋅
t
f
1
⋅
(
h
s
+
0
,
5
⋅
t
f
1
)
2
b
f
2
⋅
t
f
2
⋅
(
h
w
−
h
s
+
0
,
5
⋅
t
f
2
)
2
h
w
⋅
t
w
⋅
(
0
,
5
⋅
t
w
−
h
s
)
2
)
{\displaystyle I=\sum {\begin{pmatrix}3Eigen\\b_{f1}\cdot t_{f1}\cdot (h_{s}+0{,}5\cdot t_{f1})^{2}\\b_{f2}\cdot t_{f2}\cdot (h_{w}-h_{s}+0{,}5\cdot t_{f2})^{2}\\h_{w}\cdot t_{w}\cdot (0{,}5\cdot t_{w}-h_{s})^{2}\end{pmatrix}}}
I
=
∑
(
0,018
23
0,445
2
⋅
0,017
⋅
(
1,314
5
+
0
,
5
⋅
0,017
)
2
0
,
37
⋅
0,011
⋅
(
2
,
9
−
1,287
4
+
0,017
⋅
0
,
5
)
2
2
,
9
⋅
0,009
⋅
(
0
,
5
⋅
2
,
9
−
1,314
5
)
2
)
{\displaystyle I=\sum {\begin{pmatrix}0{,}01823\\0{,}4452\cdot 0{,}017\cdot (1{,}3145+0{,}5\cdot 0{,}017)^{2}\\0{,}37\cdot 0{,}011\cdot (2{,}9-1{,}2874+0{,}017\cdot 0{,}5)^{2}\\2{,}9\cdot 0{,}009\cdot (0{,}5\cdot 2{,}9-1{,}3145)^{2}\end{pmatrix}}}
I= 10-3∙(18,29 + 13,24 + 10,3 + 0,48)
I= 0,04232m4
Spannung σ2 im oberen Stegende
σ
2
=
−
M
⋅
z
I
+
N
A
{\displaystyle \sigma _{2}={\frac {-M\cdot z}{I}}+{\frac {N}{A}}}
σ
2
=
−
7,541
⋅
(
2
,
9
−
1,314
)
0,042
32
+
0
0,038
53
{\displaystyle \sigma _{2}={\frac {-7{,}541\cdot (2{,}9-1{,}314)}{0{,}04232}}+{\frac {0}{0{,}03853}}}
σ2 = 282,53 - 0
σ2 = 282,53N/mm²
Spannung σ1 im unteren Stegende
σ
2
=
−
7,541
⋅
(
1,314
)
0,042
32
{\displaystyle \sigma _{2}={\frac {-7{,}541\cdot (1{,}314)}{0{,}04232}}}
σ1 = - 234,23N/mm²
Spannungsnulllinie S
S
=
h
w
⋅
(
1
−
σ
2
σ
2
−
σ
1
)
=
2
,
9
⋅
(
1
−
282
,
53
282
,
53
+
234
,
23
)
{\displaystyle S=h_{w}\cdot \left(1-{\frac {\sigma _{2}}{\sigma _{2}-\sigma _{1}}}\right)=2{,}9\cdot \left(1-{\frac {282{,}53}{282{,}53+234{,}23}}\right)}
S= 1,3145m
Spannung σsl in der Steife
σ
s
l
=
−
M
⋅
z
I
+
N
A
=
−
M
⋅
(
S
−
h
w
1
)
I
+
N
A
{\displaystyle \sigma _{sl}={\frac {-M\cdot z}{I}}+{\frac {N}{A}}={\frac {-M\cdot (S-h_{w1})}{I}}+{\frac {N}{A}}}
σ
s
l
=
−
7,541,325
⋅
(
1,314
5
−
0
,
4
)
0,042
32
{\displaystyle \sigma _{sl}={\frac {-7{,}541{,}325\cdot (1{,}3145-0{,}4)}{0{,}04232}}}
σsl = - 162,96N/mm²
Der Beulnachweis wird zuerst für beide Einzelfelder geführt.
b= hw1 - tsl /2
b= MIN(S;hw ) - hw1 - tsl /2
b= 0,4 - 0,004
b= 1,3145 - 0,4 - 0,004
b= 0,396m
b= 0,9105m
Randspannungsverhältnis ψ
Ψ
=
σ
s
l
σ
1
=
−
163
−
234
{\displaystyle \Psi ={\frac {\sigma _{sl}}{\sigma _{1}}}=-{\frac {163}{-234}}}
Ψ
=
σ
2
σ
s
l
=
283
−
163
{\displaystyle \Psi ={\frac {\sigma _{2}}{\sigma _{sl}}}={\frac {283}{-163}}}
ψ= 0,695
ψ = - 1,734
Beulwert kσ Eurocode 1993-1-5 Tabelle 4.1
k
σ
=
8
,
2
1
,
05
+
Ψ
=
8
,
2
1
,
05
+
0,695
{\displaystyle k_{\sigma }={\frac {8{,}2}{1{,}05+\Psi }}={\frac {8{,}2}{1{,}05+0{,}695}}}
kσ =5,98∙(1 - ψ)² kσ =5,98∙(1 + 1,734)²
kσ = 4,697
kσ = 44,69
Beulschlankheitsgrad
λ
¯
p
{\displaystyle {\overline {\lambda }}_{p}}
(hergeleitete Formel 1)
λ
¯
p
=
b
t
w
⋅
28,121
76
⋅
ϵ
⋅
k
σ
{\displaystyle {\overline {\lambda }}_{p}={\frac {b}{t_{w}\cdot 28{,}12176\cdot \epsilon \cdot {\sqrt {k_{\sigma }}}}}}
λ
¯
p
=
b
t
w
⋅
28,121
76
⋅
ϵ
⋅
k
σ
{\displaystyle {\overline {\lambda }}_{p}={\frac {b}{t_{w}\cdot 28{,}12176\cdot \epsilon \cdot {\sqrt {k_{\sigma }}}}}}
λ
¯
p
=
0,396
0,009
⋅
28,121
76
⋅
1
⋅
4,697
{\displaystyle {\overline {\lambda }}_{p}={\frac {0{,}396}{0{,}009\cdot 28{,}12176\cdot 1\cdot {\sqrt {4{,}697}}}}}
λ
¯
p
=
0,883
4
0,009
⋅
28,121
76
⋅
1
⋅
44
,
69
{\displaystyle {\overline {\lambda }}_{p}={\frac {0{,}8834}{0{,}009\cdot 28{,}12176\cdot 1\cdot {\sqrt {44{,}69}}}}}
λ
¯
p
=
0,722
{\displaystyle {\overline {\lambda }}_{p}=0{,}722}
λ
¯
p
=
0,538
{\displaystyle {\overline {\lambda }}_{p}=0{,}538}
Abminderungsfaktor ρ (DIN 18800-2 Gleichung 81 Tabelle 27)
κ
k
=
(
0
,
97
+
0
,
03
⋅
Ψ
)
−
(
0
,
16
+
0
,
06
⋅
Ψ
)
/
λ
¯
λ
¯
{\displaystyle \kappa _{k}={\frac {(0{,}97+0{,}03\cdot \Psi )-(0{,}16+0{,}06\cdot \Psi )/{\overline {\lambda }}}{\overline {\lambda }}}}
κ
k
=
(
0
,
97
+
0
,
03
⋅
0,695
)
−
0
,
2
/
0,722
0,722
{\displaystyle \kappa _{k}={\frac {(0{,}97+0{,}03\cdot 0{,}695)-0{,}2/0{,}722}{0{,}722}}}
da
λ
¯
p
{\displaystyle {\overline {\lambda }}_{p}}
< 0,673 = >
κk = 0,9855
κk = 1
Bruttobreiten
Nach der DIN wird ähnlich vorgegangen, wie nach dem Eurocode. Zuerst werden die Bruttobreiten berechnet, daraus dann die wirksamen Breiten und zum Schluss die wirksamen Dicken.
In der DIN ist keine Begrenzung für ψ angegeben. Da es logisch erscheint, wird für negative ψ wie im Eurocode ψ=0 gesetzt.
k1 = - 0,04∙ψ² + 0,12∙ψ + 0,42 (unten)
k1 = - 0,04∙ψ² + 0,12∙ψ + 0,42 (unten)
k1 = - 0,04∙0,695² + 0,12∙0,695 + 0,42
k1 = - 0,04∙0² + 0,12∙0 + 0,42
k1 = 0,484
k1 = 0,42
k2 = + 0,04∙ψ² - 0,12∙ψ + 0,58 (oben)
k2 = + 0,04∙ψ² - 0,12∙ψ + 0,58 (oben)
k2 = + 0,04∙0,695² - 0,12∙0,695 + 0,58
k2 = + 0,04∙0² - 0,12∙0 + 0,58
k2 = 0,516
k2 = 0,58
b12 = b∙k12
bo = 0,396∙k1 = 0,396∙0,516
bo = 0, 9104∙k1 = 0, 9104∙0,58
bo = 0,2043
bo = 0,5281
bu = 0,396∙k2 = 0,396∙0,484
bu = 0, 9104∙k2 = 0, 9104∙0,42
bu = 0,1917
bu = 0,3824
wirksame Breiten
bu1,eff = bu ∙ρ = 0,1917∙0,9855
bu2,eff = bu ∙ρ = 0,3824∙1
bu1,eff = 0,1889
bu2,eff = 0,3824
bo1,eff = bo ∙ρ = 0,2043∙0,9855
bo2,eff = bo ∙ρ = 0,5281∙1
bo1,eff = 0,2013
bo2,eff = 0,528
Σbeff = 0,2013 + 0,1889
Σbeff = 0,5281 + 3824
Σbeff = 0,3902
Σbeff = 0,9104
Verlust= b - Σbeff
Verlust= b - Σbeff
Verlust= 0,396 - 0,3902
Verlust= 0,9104 - 0,9104
Verlust= 0,0058m
Verlust= 0m
Querschnittswerte der Steifen
Träger mit wirksame Breiten und Dicken
Die Querschnittswerte der Steifen ändern sich geringfügig, weil sich die Breiten geändert haben.
Asl = tw ∙(b1o + b2u + tsl ) + bsl ∙tsl
Asl = 0,009∙(0,2013 + 0,3824 + 0,008) + 0,1∙0,008
Asl = 0,0061254
x
s
l
=
t
s
l
⋅
b
s
l
⋅
(
b
s
l
2
+
t
w
/
2
)
A
s
l
{\displaystyle x_{sl}={\frac {t_{sl}\cdot b_{sl}\cdot (b_{sl2}+t_{w}/2)}{A_{sl}}}}
x
s
l
=
0,008
⋅
0
,
1
⋅
(
0
,
05
+
0,004
5
)
0,006
125
{\displaystyle x_{sl}={\frac {0{,}008\cdot 0{,}1\cdot (0{,}05+0{,}0045)}{0{,}006125}}}
xsl = 0,007118
Isl = 2 Eigen + 2 Steiner
I
s
l
=
∑
(
t
w
3
⋅
(
b
e
f
f
1
o
+
b
e
f
f
2
u
+
t
s
l
)
/
12
b
s
l
3
⋅
t
s
l
/
12
t
w
⋅
(
b
e
f
f
1
o
+
b
e
f
f
2
u
+
t
s
l
)
⋅
x
s
l
2
b
s
l
⋅
t
s
l
⋅
(
b
s
l
/
2
+
t
w
/
2
−
x
s
l
)
2
)
{\displaystyle I_{sl}=\sum {\begin{pmatrix}t_{w}^{3}\cdot (b_{eff1o}+b_{eff2u}+t_{sl})/12\\b_{sl}^{3}\cdot t_{sl}/12\\t_{w}\cdot (b_{eff1o}+b_{eff2u}+t_{sl})\cdot x_{sl}^{2}\\b_{sl}\cdot t_{sl}\cdot (b_{sl}/2+t_{w}/2-x_{sl})^{2}\end{pmatrix}}}
I
s
l
=
∑
(
0,009
3
⋅
(
0,591
7
)
/
12
0
,
1
3
⋅
0,008
/
12
0,009
⋅
(
0,591
7
)
⋅
0,007
118
2
0
,
1
⋅
0,008
⋅
(
0
,
05
+
0,004
5
−
0,007
118
)
2
)
{\displaystyle I_{sl}=\sum {\begin{pmatrix}0{,}009^{3}\cdot (0{,}5917)/12\\0{,}1^{3}\cdot 0{,}008/12\\0{,}009\cdot (0{,}5917)\cdot 0{,}007118^{2}\\0{,}1\cdot 0{,}008\cdot (0{,}05+0{,}0045-0{,}007118)^{2}\end{pmatrix}}}
Isl = (0,036 + 0,666 + 0,27 + 1,796)∙10-6
Isl = 2,768∙10-6 m4
Beulen des Gesamtfeldes
plattenartiges Verhalten
Da die DIN keine Formeln zur Berechnung der Beulwerte für ausgesteifte Plattem enthält und stattdessen auf die Literatur verweist, wird der Beulwert nach dem Eurocode berechnet.
b1 = hw1 = 0,4
b= B1 = hw = 2,9
b2 = B1 - hw = 2,5
σ
c
r
,
s
l
=
1
,
05
⋅
E
A
s
l
,
1
⋅
I
s
l
,
1
⋅
t
3
⋅
b
b
1
⋅
b
2
{\displaystyle \sigma _{cr{,}sl}={\frac {1{,}05\cdot E}{A_{sl{,}1}}}\cdot {\sqrt {\frac {I_{sl{,}1}\cdot t^{3}\cdot b}{b_{1}\cdot b_{2}}}}}
(Eurocode 1993-1-5 Gleichung A.4)
σ
c
r
,
s
l
=
1
,
05
⋅
210
⋅
10
9
0,006
125
⋅
2,768
⋅
10
−
6
⋅
0,009
3
⋅
2
,
9
0
,
4
⋅
2
,
5
{\displaystyle \sigma _{cr{,}sl}={\frac {1{,}05\cdot 210\cdot 10^{9}}{0{,}006125}}\cdot {\sqrt {\frac {2{,}768\cdot 10^{-6}\cdot 0{,}009^{3}\cdot 2{,}9}{0{,}4\cdot 2{,}5}}}}
σcr,sl = 3,6∙1013 ∙2,419∙10-6 = 8,71∙107 N/m²
σpi = 87,09∙N/mm²
Der Beulwert muss für die DIN rückgerechnet werden.
σ
e
=
190000
⋅
(
t
b
)
2
=
19000
⋅
(
0,009
2
,
9
)
2
{\displaystyle \sigma _{e}=190000\cdot \left({\frac {t}{b}}\right)^{2}=19000\cdot \left({\frac {0{,}009}{2{,}9}}\right)^{2}}
(DIN 18800-3 Element 113)
σe = 1,82996N/mm²
kσ = σpi /σe = 87,09/1,82996
kσ = 47,59
λ
¯
p
=
f
y
k
σ
p
i
=
240
87
,
09
{\displaystyle {\overline {\lambda }}_{p}={\sqrt {\frac {f_{yk}}{\sigma _{pi}}}}={\sqrt {\frac {240}{87{,}09}}}}
λ
¯
p
=
1,660
08
{\displaystyle {\overline {\lambda }}_{p}=1{,}66008}
κ
p
=
M
I
N
(
1
,
25
,
1
,
25
−
0
,
25
⋅
Ψ
)
⋅
(
1
λ
¯
−
0
,
22
λ
¯
2
)
{\displaystyle \kappa _{p}=MIN(1{,}25{,}1{,}25-0{,}25\cdot \Psi )\cdot \left({\frac {1}{\overline {\lambda }}}-{\frac {0{,}22}{{\overline {\lambda }}^{2}}}\right)}
(DIN 18800-3 Tabelle 1)
κ
p
=
1
,
25
⋅
(
1
1,660
08
−
0
,
22
1,660
08
2
)
{\displaystyle \kappa _{p}=1{,}25\cdot \left({\frac {1}{1{,}66008}}-{\frac {0{,}22}{1{,}66008^{2}}}\right)}
κp = 0,65319
knickstabähnliches Verhalten
γ
=
12
⋅
(
1
−
ν
2
)
⋅
I
h
w
⋅
t
w
3
{\displaystyle \gamma ={\frac {12\cdot (1-\nu ^{2})\cdot I}{h_{w}\cdot t_{w}^{3}}}}
(DIN 18800-3 Element 114)
γ
=
10
,
92
⋅
2,768
⋅
10
−
6
2
,
9
⋅
0,009
3
{\displaystyle \gamma ={\frac {10{,}92\cdot 2{,}768\cdot 10^{-6}}{2{,}9\cdot 0{,}009^{3}}}}
γ = 14,3
δ
=
A
t
w
⋅
h
w
=
0
,
1
⋅
0,008
0,009
⋅
2
,
9
{\displaystyle \delta ={\frac {A}{t_{w}\cdot h_{w}}}={\frac {0{,}1\cdot 0{,}008}{0{,}009\cdot 2{,}9}}}
(DIN 18800-3 Element 114)
δ = 0,0306
k
=
0
,
5
⋅
(
1
+
0
,
34
⋅
(
λ
¯
p
−
0
,
2
)
+
λ
¯
p
2
)
{\displaystyle k=0{,}5\cdot \left(1+0{,}34\cdot \left({\overline {\lambda }}_{p}-0{,}2\right)+{\overline {\lambda }}_{p}^{2}\right)}
k= 0,5∙(1 + 0,34∙(1,66008 - 0,2) + 1,66008²)
k= 2,126
κ
k
=
1
k
+
k
2
−
λ
¯
p
2
=
1
2,126
+
2,126
2
−
1,660
08
2
{\displaystyle \kappa _{k}={\frac {1}{k+{\sqrt {k^{2}-{\overline {\lambda }}_{p}^{2}}}}}={\frac {1}{2{,}126+{\sqrt {2{,}126^{2}-1{,}66008^{2}}}}}}
κk = 0,2895
Interaktion
σ
p
i
σ
k
i
=
k
σ
⋅
α
2
⋅
1
+
Σ
δ
L
1
+
Σ
γ
L
{\displaystyle {\frac {\sigma _{pi}}{\sigma _{ki}}}=k_{\sigma }\cdot \alpha ^{2}\cdot {\frac {1+\Sigma \delta _{L}}{1+\Sigma \gamma _{L}}}}
(DIN 18800-3 Gleichung 23)
σ
p
i
σ
k
i
=
47
,
59
⋅
(
7
,
1
2
,
9
)
2
⋅
1
+
0,030
6
1
+
14
,
3
{\displaystyle {\frac {\sigma _{pi}}{\sigma _{ki}}}=47{,}59\cdot \left({\frac {7{,}1}{2{,}9}}\right)^{2}\cdot {\frac {1+0{,}0306}{1+14{,}3}}}
σ
p
i
σ
k
i
=
19
,
21
{\displaystyle {\frac {\sigma _{pi}}{\sigma _{ki}}}=19{,}21}
Λ=
λ
¯
p
2
{\displaystyle {\overline {\lambda }}_{p}^{2}}
+ 0,5 und 2< Λ <4(DIN 18800-3 Gleichung 22)
Λ= 1,66008² + 0,5
Λ= 3,256
ρ
=
Λ
−
σ
p
i
/
σ
k
i
Λ
−
1
{\displaystyle \rho ={\frac {\Lambda -\sigma _{pi}/\sigma _{ki}}{\Lambda -1}}}
und 0 < ρ < 1(DIN 18800-3 Gleichung 21)
ρ
=
3,256
−
19
,
21
3,256
−
1
{\displaystyle \rho ={\frac {3{,}256-19{,}21}{3{,}256-1}}}
ρ= 0
κpx = (1 - ρ²)∙κp + ρ²∙κk (DIN 18800-3 Gleichung 24)
κpx = (1 - 0²)∙0,653 + 1²∙0,2895
κpx = 0,65319
σd = 234N/mm²
σp,Rd = fyd ∙MIN(κ1 ;κ2 ;κpx )= 240∙0,653/1,1
mit κ1 und κ2 als Abminderungsfaktoren für Einzelfeldbeulen
σp,Rd = 142,51
σ
d
σ
p
,
R
d
=
234
,
23
142
,
51
<
1
{\displaystyle {\frac {\sigma _{d}}{\sigma _{p{,}Rd}}}={\frac {234{,}23}{142{,}51}}<1}
(DIN 18800-3 Gleichung 11)
1
,
64
≮
1
{\displaystyle 1{,}64\not <1}
Nachweis nicht erfüllt.
Da die DIN keine Formel für einen Schubbeulwert mit Längssteifen enthält, wird die Formel aus dem Eurocode verwendet. Da auch der Rechenweg bis
λ
¯
{\displaystyle {\overline {\lambda }}}
gleich ist, werden die Werte bis dahin übernommen.
kτ = 8,2233
λ
¯
p
=
h
w
37,010
3
⋅
t
⋅
ϵ
⋅
k
τ
{\displaystyle {\overline {\lambda }}_{p}={\frac {h_{w}}{37{,}0103\cdot t\cdot \epsilon \cdot {\sqrt {k_{\tau }}}}}}
Hergeleitete Formel 2
λ
¯
p
=
2
,
9
37,010
3
⋅
0,009
⋅
ϵ
⋅
8,223
3
{\displaystyle {\overline {\lambda }}_{p}={\frac {2{,}9}{37{,}0103\cdot 0{,}009\cdot \epsilon \cdot {\sqrt {8{,}2233}}}}}
λ
¯
p
=
3,034
{\displaystyle {\overline {\lambda }}_{p}=3{,}034}
Die Berechnung der Schubschlankheit für das Einzelfeld ist mit dem Eurocode identisch. Der Wert wird übernommen.
λ
¯
p
=
3,073
{\displaystyle {\overline {\lambda }}_{p}=3{,}073}
Einzelfeldbeulen ist maßgebend.
λ
¯
p
{\displaystyle {\overline {\lambda }}_{p}}
= MIN(3,034;3,073)= 3,073
Für
λ
¯
p
{\displaystyle {\overline {\lambda }}_{p}}
> 1,38 und Beulfeld mit Längssteifen gilt
κ
τ
=
1
,
16
λ
¯
p
2
=
1
,
16
3,073
2
{\displaystyle \kappa _{\tau }={\frac {1{,}16}{{\overline {\lambda }}_{p}^{2}}}={\frac {1{,}16}{3{,}073^{2}}}}
(DIN 18800-3 Tabelle 1)
κτ = 0,12286
Nachweis
τ
d
=
V
A
=
1,142
625
2
,
9
⋅
0,009
{\displaystyle \tau _{d}={\frac {V}{A}}={\frac {1{,}142625}{2{,}9\cdot 0{,}009}}}
τd = 43,78N/mm²
τ
P
,
R
d
=
f
y
k
⋅
κ
τ
3
⋅
γ
=
240
⋅
0,122
86
3
⋅
1
,
1
{\displaystyle \tau _{P{,}Rd}={\frac {f_{yk}\cdot \kappa _{\tau }}{{\sqrt {3}}\cdot \gamma }}={\frac {240\cdot 0{,}12286}{{\sqrt {3}}\cdot 1{,}1}}}
τP,Rd = 15,47N/mm²
τ
d
τ
P
,
R
d
=
43
,
78
15
,
47
{\displaystyle {\frac {\tau _{d}}{\tau _{P{,}Rd}}}={\frac {43{,}78}{15{,}47}}}
(DIN 18800-3 Gleichung 12)
2,828
7
≮
1
{\displaystyle 2{,}8287\not <1}
Nachweis nicht erfüllt
F= 330kN
ss = 0,1m
c= ss + 2∙tf2 = 0,1 + 2∙0,011
c= 0,122
α
=
a
b
=
7
,
1
2
,
9
{\displaystyle \alpha ={\frac {a}{b}}={\frac {7{,}1}{2{,}9}}}
α= 2,4482
β
=
c
a
=
0,122
7
,
1
{\displaystyle \beta ={\frac {c}{a}}={\frac {0{,}122}{7{,}1}}}
ß= 0,01718
Aus der Tabelle kann entnommen werden
Auszug aus Tabelle der Beulwerte für α und ß
ß↓ α→
2
3
0
1,17
0,73
0,1
1,21
0,79
z
=
z
l
o
+
(
z
r
o
−
z
l
o
)
⋅
x
−
x
1
x
2
−
x
1
+
(
z
l
u
−
z
l
o
+
(
z
r
u
−
z
l
u
+
z
l
o
−
z
r
o
)
⋅
(
x
−
x
1
x
2
−
x
1
)
)
⋅
(
y
−
y
1
y
2
−
y
1
)
{\displaystyle z=z_{lo}+(z_{ro}-z_{lo})\cdot {\frac {x-x_{1}}{x_{2}-x_{1}}}+\left(z_{lu}-z_{lo}+(z_{ru}-z_{lu}+z_{lo}-z_{ro})\cdot \left({\frac {x-x_{1}}{x_{2}-x_{1}}}\right)\right)\cdot \left({\frac {y-y_{1}}{y_{2}-y_{1}}}\right)}
k
σ
y
=
1
,
17
+
(
0
,
73
−
1
,
17
)
⋅
2
,
45
−
2
3
−
2
+
(
1
,
21
−
1
,
17
+
(
0
,
79
−
1
,
21
+
1
,
17
−
0
,
73
)
⋅
(
2
,
45
−
2
3
−
2
)
)
⋅
(
0,017
1
−
0
0
,
1
−
0
)
{\displaystyle k_{\sigma y}=1{,}17+(0{,}73-1{,}17)\cdot {\frac {2{,}45-2}{3-2}}+\left(1{,}21-1{,}17+(0{,}79-1{,}21+1{,}17-0{,}73)\cdot \left({\frac {2{,}45-2}{3-2}}\right)\right)\cdot \left({\frac {0{,}0171-0}{0{,}1-0}}\right)}
kσy = 1,17 - 0,198 + (0,04 + 0,02∙0,45)∙0,171
kσy = 0,981
σe = 1,82996N/mm²
σy,pi = kσy ∙σe ∙a/c
σy,pi = 0,981∙1,82996∙7,1/0,122
σy,pi = 104,49N/mm²
λ
¯
p
y
=
f
y
k
σ
y
,
p
i
=
240
104
,
49
{\displaystyle {\overline {\lambda }}_{py}={\sqrt {\frac {f_{yk}}{\sigma _{y{,}pi}}}}={\sqrt {\frac {240}{104{,}49}}}}
λ
¯
p
y
=
1,516
{\displaystyle {\overline {\lambda }}_{py}=1{,}516}
κ
y
=
(
1
λ
¯
−
0
,
22
λ
¯
2
)
{\displaystyle \kappa _{y}=\left({\frac {1}{\overline {\lambda }}}-{\frac {0{,}22}{{\overline {\lambda }}^{2}}}\right)}
(DIN 18800-3 Tabelle 1)
κ
y
=
(
1
1,516
−
0
,
22
1,516
2
)
{\displaystyle \kappa _{y}=\left({\frac {1}{1{,}516}}-{\frac {0{,}22}{1{,}516^{2}}}\right)}
κy = 0,56405
σyki = 1,88•σe = 3,437N/mm²
Es wird laut DIN die Beulschlankheit
λ
¯
p
y
{\displaystyle {\overline {\lambda }}_{py}}
verwendet. Der Eurocode hingegen verlangt die Knickschlankheit
λ
¯
k
i
,
y
{\displaystyle {\overline {\lambda }}_{ki{,}y}}
.
k
=
0
,
5
⋅
(
1
+
0
,
34
⋅
(
λ
¯
p
y
−
0
,
2
)
+
λ
¯
p
y
2
)
{\displaystyle k=0{,}5\cdot \left(1+0{,}34\cdot \left({\overline {\lambda }}_{py}-0{,}2\right)+{\overline {\lambda }}_{py}^{2}\right)}
k= 0,5∙(1 + 0,34∙(1,516 - 0,2) + 1,516²)
k= 1,872
κ
k
=
1
k
+
k
2
−
λ
¯
p
2
{\displaystyle \kappa _{k}={\frac {1}{k+{\sqrt {k^{2}-{\overline {\lambda }}_{p^{2}}}}}}}
κ
k
=
1
1,872
+
1,872
2
−
1,516
2
{\displaystyle \kappa _{k}={\frac {1}{1{,}872+{\sqrt {1{,}872^{2}-1{,}516^{2}}}}}}
κk = 0,33659
σ
y
,
p
i
σ
y
k
i
=
104
,
49
3,437
=
30
,
41
{\displaystyle {\frac {\sigma _{y{,}pi}}{\sigma _{yki}}}={\frac {104{,}49}{3{,}437}}=30{,}41}
Λ=
λ
¯
p
2
{\displaystyle {\overline {\lambda }}_{p}^{2}}
+ 0,5 und 2< Λ <4(DIN 18800-3 Gleichung 22)
Λ= 1,516² + 0,5
Λ= 2,797
ρ
=
M
i
n
(
M
a
x
(
Λ
−
σ
p
i
/
σ
k
i
Λ
−
1
;
0
)
;
1
)
{\displaystyle \rho =Min\left(Max\left({\frac {\Lambda -\sigma _{pi}/\sigma _{ki}}{\Lambda -1}};0\right);1\right)}
(DIN 18800-3 Gleichung 21)
ρ
=
2,797
−
30
,
41
2,797
−
1
{\displaystyle \rho ={\frac {2{,}797-30{,}41}{2{,}797-1}}}
ρ= 0
κpx = (1 - ρ²)∙κp + ρ²∙κk (DIN 18800-3 Gleichung 24)
κpx = (1 - 0²)∙0,56405 + 1²∙0,33659
κpx = 0,56405
σP,Rd = fyd ∙ κpx = 240∙0,56405/1,1
σP,Rd = 123,06
σy = F/(c∙tw )= 330/(0,122∙0,009)
σy = 300,5N/mm²
Nachweis
σ
y
σ
P
,
R
d
=
300
,
5
123
,
06
{\displaystyle {\frac {\sigma _{y}}{\sigma _{P{,}Rd}}}={\frac {300{,}5}{123{,}06}}}
σ
y
σ
P
,
R
d
=
2,442
{\displaystyle {\frac {\sigma _{y}}{\sigma _{P{,}Rd}}}=2{,}442}
κx = 0,65319
Nachweis η1 : 1,6436
κy = 0,56405
Nachweis η2 : 2,4422
κτ = 0,12286
Nachweis η3 : 2,8287
e1 = 1 + κx 4 = 1 + 0,653194 (DIN 18800-3 Gleichung 15)
e1 = 1,182
e2 = 1 + κy 4 = 1 + 0,564054 (DIN 18800-3 Gleichung 16)
e2 = 1,101
e3 = 1 + κx ∙ κy ∙ κτ ² = 1 + 0,65319∙0,56405∙0,12286² (DIN 18800-3 Gleichung 17)
e3 = 1,005
V= (κx ∙ κy )6 = (0,653∙0,564)6
V= 0,0025
(
|
σ
x
|
σ
x
P
,
R
,
d
)
e
1
+
(
|
σ
y
|
σ
y
P
,
R
,
d
)
e
1
+
(
τ
τ
P
,
R
,
d
)
e
3
−
V
⋅
(
|
σ
x
⋅
σ
y
|
σ
x
P
,
R
,
d
⋅
σ
x
P
,
R
,
d
)
{\displaystyle \left({\frac {|\sigma _{x}|}{\sigma _{xP{,}R{,}d}}}\right)^{e_{1}}+\left({\frac {|\sigma _{y}|}{\sigma _{yP{,}R{,}d}}}\right)^{e_{1}}+\left({\frac {\tau }{\tau _{P{,}R{,}d}}}\right)^{e_{3}}-V\cdot \left({\frac {|\sigma _{x}\cdot \sigma _{y}|}{\sigma _{xP{,}R{,}d}\cdot \sigma _{xP{,}R{,}d}}}\right)}
< 1 (Gleichung 14)
1,6441,182 + 2,4421,101 + 2,8291,005 - 0,0025∙1,644∙2,442
7,3074 > 1
Nachweis nicht erfüllt
Allgemein:Inhaltsverzeichnis ; Glossar ; Zahlen
Rechenbeispiel: Allgemeiner Lösungsweg ; erstes ; zweites ; drittes ; viertes
Norm: EuroB ;DINS ;EuroS ;DINB ;Zusammenfassung ;Variation der Geometrie