DESIGN OF SIMPLY-SUPPORTED AND CONTINUOUS BEAMS IN STEEL-CONCRETE COMPOSITE CONSTRUCTION

摘要

Steel-concrete composite beams in Australia are predominantly designed as simply-supported with web-side-plate steel connections, which has some structural limitations. The inevitable slope discontinuity at internal supports can cause wide cracks, whilst its remedy, sufficient tension reinforcement to control cracking, can overload the cleat of the web-side-plate connection, which is in corresponding compression. Continuous composite beams offer better crack control and lower deflections, even when the depth of the steel section is less than that required for the equivalent simply-supported beam. Innovative design methods for continuous and semi-continuous composite beams have recently been developed which eliminate the need for iterative approaches and allow accurate preliminary sizing of members. This paper reviews the design of simply-supported and continuous composite beams in Australia, highlighting the benefits of continuous construction with two typical design examples.