Precast Segmental Deck Erection with Launching Gantry vs. Progressive Cantilever Method with Stays – Impact of the Construction Method on the Final Design
Abstract:
By and large there are two methods for span-by-span erection of precast segmental bridges – launching gantries and the progressive cantilever method with stays (PCMS). The use of gantries, in various configurations, sees worldwide use for road and rail decks, whereas PCMS applications are mostly local to France (where the method originated) and recently the UK.
Whilst the design basis for each project creates unique sets of constraints in terms of loading, seismicity, operational criteria etc. which creates difficulties when comparing the efficiencies of the built solutions, one aspect that depends exclusively on the deck erection method is the impact of the temporary works on the permanent works.
The presentation will review and compare that interface for both methods, from various perspectives such as erection cycles, equipment weight, segment delivery, span and prestressing arrangement, temporary prestressing, Contractor expertise and design effort. The aim is to give the audience an informed view of the pros and cons of each erection method, gathered from detailed design experience on both, to hopefully assist in discussions/decisions on future bridge projects.
Presenter:
Joao Milheiro, Senior Chartered Engineer, SYSTRA
Joao has a Master’s Degree in Civil Structural Engineering and is currently a Bridges Technical Expert at SYSTRA. He has 18 years of experience in analysis, design and refurbishment of highway bridges, railway bridges and footbridges as Designer, Structures Team Leader or Category 3 Checker. He is currently working on the Cable-Stayed Bridge for West Seattle Link Extension.
