Initially conceived for in-place casting with advancing shoring, span-by-span construction of prestressed-concrete bridges was soon extended to self-launching gantry erection of precast segmental bridges and span-by-span casting with movable scaffolding systems (MMS).
Span-by-span assembly of simply-supported precast segmental spans is the typical construction method for light-rail transit bridges with box-girder and dual-track U-section. Large-scale highway projects combine span-by-span erection with in-place casting of wet joints to achieve full structural continuity, diminish the number of bearings and expansion joints, and control the propagation of the geometry errors of short-line match casting.
Span-by-Span Erection of Precast Segmental Bridges: Introduction explores the temporary static schemes of span-by-span construction of precast segmental bridges, the corresponding post-tensioning systems and locked-in stresses, the stiffness interactions to consider for bridge design, and staged application of post-tensioning to avoid opening of the epoxy joints and the risk of brittle span failure.
The eManual discusses span assembly on shoring towers and the different means and methods to strand-jack into position precast segmental spans delivered on barges in marine operations. It introduces the different types of self-launching gantries for span-by-span erection of precast segmental bridges and explores the span assembly operations common to all types of gantries.
The eManual provides an exhaustive introduction to span-by-span construction of precast segmental bridges for bridge owners, designers and constructors interested in this construction method. Specific monographs of the eManuals project explore the different families of self-launching gantries in great detail.