section modulus 012004
DESCRIPTION
desainTRANSCRIPT
The loss of the DerbyshireProject NA 240A
Appendix
1
Section modulus calculations for stiffeners and girdersRequirements are based on the class rules from Det Norske Veritas
b Original design
Toppflange Longitudinal stiffeners Input
63 cm
Toppflange thickness t 1.05 cm
Web height h 63.5 cm
Neutral axis Web thickness t 1.05 cm
Bottom flange bredth b 28 cm
Web t h Bottom flange thickness t 2.5 cm
6772
202.8
Flange 33.4 cm
Moment of inertia 161875
4809
Design rules
Span l 3.68 m
(DnV Part 3, Ch 7 Sec 3 C400) Spacing b 0.994 m
Design pressure 17.17
Required Z 204
Original design Original design
Side girder Input Center girder Input
Toppflange breadth b 368 cm Toppflange breadth b 368 cm
Toppflange thickness t 1.05 cm Toppflange thickness t 1.05 cm
Web height h 56 cm Web height h 91 cm
Web thickness t 1.05 cm Web thickness t 1.05 cm
Bottom flange bredth b 10 cm Bottom flange bredth b 7.5 cm
Bottom flange thickness t 2.5 cm Bottom flange thickness t 2.5 cm
20983 35128
408.4 438.9
51.4 cm 80.0 cm
Moment of inertia 119703 Moment of inertia 340239
2330 4251
Design rules Design rules
Span l 11 m Span l 11 m
Spacing b 3.68 m Spacing b 3.68 m
Design pressure 17.17 Design pressure 17.17
Required Z 8133 Required Z 8133
t Toppflange eff breadth be
zS xiAi cm3
S Ai cm2
Neutral axis z
t b cm4
Section Modulus Z cm3
Effective flange of the girder: be = 0.84 b
Effective flange of the stiffners: be = 60 * t (web) kN/m2
cm3
S xiAi cm3 S xiAi cm3
S Ai cm2 S Ai cm2
Neutral axis z Neutral axis z
cm4 cm4
Section Modulus Z cm3 Section Modulus Z cm3
kN/m2 kN/m2
cm3 cm3
The loss of the DerbyshireProject NA 240A
Appendix
2
Original design, 14.72 m span Faulkner's design
Longitudinal stiffener Input Transverse stiffener Input
63 cm 63 cm
Toppflange thickness t 1.05 cm Toppflange thickness t 1.05 cm
Web height h 63.5 cm Web height h 63.5 cm
Web thickness t 1.05 cm Web thickness t 1.05 cm
Bottom flange bredth b 28 cm Bottom flange bredth b 28 cm
Bottom flange thickness t 2.5 cm Bottom flange thickness t 2.5 cm
6772 6772
202.8 202.8
33.4 cm 33.4 cm
Moment of inertia 161875 Moment of inertia 161875
4809 4809
Design rules Design rules
Span l 14.72 m Span l 11 m
Spacing b 0.994 m Spacing b 0.981 m
Design pressure 17.17 Design pressure 17.17
Required Z 3265 Required Z 2168
Our suggestion Our suggestion
All girders Input Longitudinal stiffeners Input
Toppflange breadth b 368 cm 63 cm
Toppflange thickness t 1.05 cm Toppflange thickness t 1.05 cm
Web height h 90 cm Web height h 20 cm
Web thickness t 1.05 cm Web thickness t 1.05 cm
Bottom flange bredth b 30 cm Bottom flange bredth b 7.5 cm
Bottom flange thickness t 2.5 cm Bottom flange thickness t 1.5 cm
34776 1707
494.1 98.4
70.4 cm 17.3 cm
Moment of inertia 625275 Moment of inertia 5691
8883 328
Design rules Design rules
Span l 11 m Span l 3.68 m
Spacing b 3.68 m Spacing b 0.994 m
Design pressure 17.17 Design pressure 17.17
Required Z 8133 Required Z 204
Toppflange eff breadth be Toppflange eff breadth be
S xiAi cm3 S xiAi cm3
S Ai cm2 S Ai cm2
Neutral axis z Neutral axis z
cm4 cm4
Section Modulus Z cm3 Section Modulus Z cm3
kN/m2 kN/m2
cm3 cm3
Toppflange eff breadth be
S xiAi cm3 S xiAi cm3
S Ai cm2 S Ai cm2
Neutral axis z Neutral axis z
cm4 cm4
Section Modulus Z cm3 Section Modulus Z cm3
kN/m2 kN/m2
cm3 cm3