Transcript London Millennium Bridge Presentation.pptx

Mike O’Malley
Kelly Fraher
Francis Kelly
Problems
 Swaying noticed
 Bridge closed
 Already £2.2million over budget - bridge failure
 Solutions to problem needed…
1St Solution – Stiffening
(so that the frequency of the bridge and footsteps don’t match)
 This option was not feasible
 Appearance?
 Cost?
 Time?
 …needed to be at least ten times stiffer
nd
2
Solution - Damping
 Passive Damping – only viable option (active dampers
too complex)
 2 types: viscous and tuned mass
 Viscous – lateral sway (piston in oil…shock absorbers
in cars)
 Tuned mass – vertical movement (weights on springs
opposing phase movement of the bridge)…precaution
Conclusions
 Since corrected - no problems have occurred