With back spans of 228m and 216m and a central span of 1418m, the
Tsing Lung bridge would have been the third longest long-span suspension bridge in the world (at that time). For political reasons known only to them, the Hong Kong Government decided to shelve the bridge indefinitely.
I worked on the bridge as part of the team doing the Category III (fully independant) design check of the bridge when I worked for Mott MacDonald. (Mott Connell (refer to link) is part of the Mott MacDonald Group). My job was to check the reinforced concrete towers and also to check the classifications of weld of the orthotropic steel box-girder deck under fatigue loading.
The deck was determined as being satisfactory but the towers were found to be locally overstressed at their intersection with the cross-beam at deck level under transverse loading (a right-angle or similar re-entrant corner will always cause a (theoretically infinite at the root) stress concentration. The provision of a haunch fillet was recommended accordingly.
So, with an answer of 1420m; incredibly just 2m from the correct answer, the winner is...
BobbyDigital!
Congratulations to you Sir.
If you would like to PM me with your name and address written
exactly how I should write it on the parcel, it will be my pleasure to send this off to you.
Thank you to all who entered.
Sorry that there can only be one winner.
Better luck next time...
