Span-by-span casting with movable scaffolding systems (MSS) is a high-quality alternative to precast segmental construction in large-scale bridge projects, and definitely a more affordable technology in medium-length bridges.
Less post-tensioning, simpler bridge design, much simpler geometry control, only one construction joint per span, and continuous reinforcement in that only joint lead to high-quality, durable bridges with long service life and low maintenance costs. MSS technology also avoids the cost of precasting facility and segment transportation means, and self-launching MSS minimize the demand for labor and auxiliary equipment and can be equipped with multiple production support systems.
In 41 pages, Movable Scaffolding Systems (MSS): Introduction illustrates span-by-span casting with MSS through comparisons with the other construction methods for medium-span prestressed-concrete bridges. It explores one-phase casting of box girders and ribbed slabs with double-T section and two-phase casting of box girders with and without first-phase post-tensioning. It also discusses multi-phase casting of wide box girders combining in-place precasting of pier tables, two-phase casting with MSS of the central box core, and segmental casting of the side wings with forming carriages rolling on the central core.
For each span casting method, the eManual explores the prefabrication techniques for the rebar cage and their impacts on the span cycle time, the filling sequences for the casting cell, the design of post-tensioning, and staged application of post-tensioning to control structure-equipment interaction.
With extensive illustrations, the eManual introduces the different types of MSS and provides exhaustive guidance on the choice of the most appropriate type. It also explains how to design bridge piers, abutments and superstructures for effective use of MSS technology in relation to the staged casting process selected for the span.
The eManual introduces span-by-span casting with MSS to bridge owners, designers and constructors unfamiliar with this construction method, and is an indispensable gateway to specialized monographs of the eManuals project dealing with the different types of MSS.