Week 7 Challenge
Given Data:
Total Length of Bridge = 90m
Span of Bridge = 45m
H.F.L above foundation Level = 2m
Mean Velocity of River = 3m/s
Height of Pier from foundation Level = 7.5m
Size of Pier = 1.2m dia (Assumed)
Depth of Deck Slab = 0.3m
Four longitudinal I- Girders are also assumed with 3m spacing between the girders having 2m depth of the section, 1.2m width of flange, 0.6m thickness of web & flange.
Seven Cross beams are also assumed at 15m distance each beam having 1.2m depth and 1m width of the beam.
Water Current Forces load Calculation:
As per IRC: 6-2014, P = 52KV2
As I have circular piers so shape factor K = 0.66
Height of H.F.L from foundation is 2m so water forces will be acting at 2m height of piers so,
Maximum Velocity, V = `square root`2 x Vmean
Mean Velocity = 3 m/sec (Given)
So, V = square root`2 x 3
V= 4.24
Water Current Force, P = 52 x K X V2
= 52 x 0.66 x 4.24 x 4.24
P = 616.99 kN/m2
As Pier size is 1.2m dia so final P = 1.2 X 616.99 = 740.38kN/m2
Staad Pro Modelling and Analysis:
First I created the model in staad pro as per the given data. Where I modeled my bridge as per the given data. After that I defined the properties as per given data, then I provide fixed support to the piers.
After that I define the load cases. Where I defined two load cases for my structure.
Load case 1: I go to the load case 1 where i go to member load then linear varying load. And gave load W2=740.38kN/m2 in local Z direction and assigned it to the pier at a height of 2m.
Load case 2: I go to the load case 2 where i go to member load then linear varying load. And gave load W2=-740.38kN/m2(For opposite direction) in local Z direction and assigned it to the pier at a height of 2m.
After that I gave the run analysis command and goes to the Post Processing mode.
Where i firstely select the Beams and go to the reports, section forces and checked for the Maximum Bending Moment in MY for load cases. Where I got maximun bending moment in MY 463.933kN-m.
After that i again select the Beams and go to the reports, section forces and checked for the Maximum Bending Moment in MZ for load cases. Where I got maximun bending moment in MZ 0.836kN-m
After that i again select the Beams and go to the reports, section forces and checked for the Maximum Shear Force in FY for load cases. Where I got maximun Shear Force in FY 0.162kN
After that i again select the Beams and go to the reports, section forces and checked for the Maximum Shear Force in FZ for load cases. Where I got maximun Shear Force in FZ 740.966kN.
