Movable bridges

This chapter is an elementary introduction to movable bridge engineering. Movable bridges are classified and various types are described and illustrated with examples built in the United Kingdom, Europe, and America. Span drive and stabilising machinery is treated and the interdependency between the superstructure, mechanical and hydraulic machinery, and electrical controls is emphasised. A movable bridge is a machine and, as such, dynamic effects should be considered. Major design issues, including safety and redundancy, are discussed as well as design specifications and future trends in the architecture and engineering of movable bridges.