QUEENSFERRY CROSSING II . Specimen Design
Rendering : DISSING + WEITLING architecture
1 . BACKGROUND
The need for the new crossing arose following a detailed inspection of the Forth Road Bridge in 2004 . During an internal inspection of the main cables serious corrosion was discovered which , if left unchecked , could lead to the bridge being closed to heavy goods vehicles as early as 2014 and to all traffic by 2019 .
The Forth Estuary Transport Authority ( FETA ) ( NB : the organisation that operated the road bridge then – since 2015 it has been operated by Amey ) initiated a programme to dehumidify the main cables in an attempt to arrest deterioration . The first of three dehumidification plants came into operation in February 2008 and cable inspections at that time showed an improved prognosis for the bridge .
The inspection indicated that with the assessed rate of deterioration restrictions to heavy goods vehicles were more likely to be considered at a later date , between 2017 and 2021 . A refurbished
Forth Road Bridge would be able to continue to carry pedestrian and cycle traffic as well as serve as a transport corridor for buses .
2 . INTRODUCTION
The Queensferry Crossing is a landmark 21st century structure designed to complement the adjacent 20th century Forth Road Bridge and the historic 19th century Forth Railway Bridge . As with its illustrious predecessors the new crossing will span the Forth Estuary maintaining vital connections between Edinburgh and Fife . On completion , this project will create the longest three tower cable-stayed bridge in the world and also by far the largest to feature cables which cross at mid-span . This stiffening method provides extra strength and stiffness , stabilises the central tower and at the same time allows the towers and the deck to be more slender and elegant .
1 / 2017