Queensferry Crossing
08/02/2024
Basis
Connects Fife to Edinburgh and the
Lothians
Improves connection to the North
Main cable of existing bridge no longer fit
for purpose
Key Information
Cost of £1.36 Billion
Total span of 2.6km
650m main span
Tower height of 210m
Longest pair of freestanding cantilevers in
the world
maps.google.com
Delivery
8% under the minimum expected cost
Delayed by eight months
Designed by Ramboll, Sweco, Leonhardt,
and Andrä and Parnter
Bult by Dragados, Hochtief, American
Bridge International, and Morisson
Construction
Timeline
2007
Feasibility Study
2008 Project anounced
2011
Act passed
Tender Awarded
2013
Design started
Construction started
Connecting roads finished
2017
Construction
Finished
Structure - Main Span
Three-cell composite box girder construction
460mm slab with transverse prestressing
Transverse frames provide transverse stiffness
Trapezoidal stiffeners provide longitudinal stiffness
Anchorages mounted on the inner web of the central box
CIBSE Journal
Svendsen, Martin & Lollesgaard, Martin & Hansen, Svend. (2013).
Wind Effects on the Forth Replacement Crossing.
Structure - cables
144 stay cables
Up to 421m long
Service life - 60 years
Designed for “cable-out” operation
Overlapping on main spans
Anchorages on inner webs in main spans,
outer on back spans
Helical ribbing
Fitted with friction dampers
Dehumidification fitted
New Civil Engineer
Construction
Towers:
1. Caissons
2. In-situ casting of towers
Balanced cantilever sections with prefabricated segments:
1. Starting segments lifted and installed - cantilever arms
formed
2. Starting segment cables installed and tensioned
3. Balanced cantilever approach used, lifting section by
section
Caisson - forthbridges.org
Tower formwork - forthbridges.org
Cantilever arms - forthbridges.org
Influence of Forth Road Bridge
Cable replacement possible
Wind baffles
Expansion joint placement
Dehumidification in stay cables
Lessons learned from QC
Ice formation/ snow buildup
Port management with concrete pours
Importance of checking equipment
Wind Baffle - Bear Scotland