Technical Advances of Temporary Facilities for the Failure Prevention of Large-Span Cantilever Casting Construction of Mountainous Concrete Box-Type Arch Bridges

Table 1

Comparisons among different mainstream form travelers.

Form travelers	Characteristics	Advantages	Defects
European style	Use truss bottom frame, with the side-stayed bars hinged with the cross beams	Lower center of gravity, explicit force transmission, and large capacity	Huge deformations in the transverse mid span of the front-end, difficult movement, and blocking the buckles
Japanese style	Upstrike diamond-shaped form traveler, evolved from adding an oblique pushing device to the support positions of a traditional one used for concrete continuous girder bridges	Small deformation	High center of gravity and excessive conflicts with the buckles
Chuan style	Developed by simplifying the bottom frame of the European style into a truss plane and adding a hanger	Convenient movement	Complex force transmission on the hanger, cross beam subjected to huge forces and carrying difficulties, and low capacity and large deformation of the front-end of the bottom plane