ABSTRACT
Abstract This pape r examine s th e feasibilit y o f usin g jointless , thermall y restraine d construction fo r railwa y viaducts . Prim a facie , i t demonstrate s tha t suc h superstructures ar e technically acceptabl e fo r both strengt h an d fatigu e limi t states . It als o show s tha t th e abutment s an d pier s ca n b e designe d satisfactorily . Suc h construction is most likely to be economic fo r multispan viaducts . I t is likely to show considerable economie s i n service ; unlik e conventiona l construction , ther e ar e n o incompatibilities o f therma l movemen t betwee n th e rails , superstructur e an d substructure, maintenanc e costs shoul d therefore be reduced. Key words : continuous , bridges , steel , railway , jointless, maintenanc e
1 Introductio n
Steel viaduct s ca n b e designe d u p t o an y lengt h withou t movemen t joints . Suc h viaducts woul d b e particularl y suitable fo r hig h speed railways . Th e behaviour o f a jointless viaduc t under thermal and live loading woul d be essentially th e same as the behaviour o f th e continuou s welde d railwa y track . Th e absence o f an y expansio n joints in the structure obviates th e need for any joints or other special measures in the track construction . I t also eliminate s source s o f noise at bearings an d joints durin g passage o f trains.
