Quick methods of analysing earthquake forces on viaduct bridges having continuous decks and tall piers

Bibliography: leaf 87.
The available methods of calculating the effects of earthquakes on viaduct-type bridges with continuous decks and tall piers are examined. Particular emphasis is laid on the use of a relatively quick method of analysis using response spectra and taking account of the effects of damping. The use of this method is illustrated by applying it to a mathematical model representing a real. bridge. Manual calculations are performed and refined by the application of Rayleigh's Principle. A number of variations to the configuration of the model are analysed by the computer programme "SAP IV" under earthquake excitation in each of three mutually perpendicular directions. The computed results are compared with those obtained by manual calculation. The earthquake loading effects are compared with the effects of deadload, traffic loading and windload and there is a discussion on the design of suitable structural configurations to contend with seismic loading. The work ends with some generalisations about other types of bridges.