The Structural Behaviour of Composite Connections With Steel Beams and Precast Hollow Core Slabs

Abstract

ABSTRACT:The use of composite precast hollowcore floor system has been rapidly increased in U.K. and the international construction market due to its various advantages. However, this composite system is mainly used as simply supported beam, without considering the moment behaviour of the connections. Therefore, little research on the composite joint behaviour of this connection has been conducted so far. In this paper, using the general purpose finite element software ABAQUS, a three dimensional model of the composite joint was set up to simulate the semi-rigid composite beam-column connections of the composite beams with precast hollowcore slabs. Using the proposed model, the numerical studies using 3-D Finite element modelling techniques were carried out. Against with the full scale test results of the author, the structural behaviour of this type of connections was studied.Keywords: Connection; semi-rigid;, finite element; connection; modelling INTRODUCTIONIn the building construction, precast hollowcore slab is a newly developed floor system with limited research. Compared with the traditional composite floor system like the solid slabs or metal profiled decking floor system, it saves construction time; reduce the cost of concrete casting, etc. Therefore, it becomes more and more popular in the construction market. In the construction practice, the composite beams with precast slabs are used as simply supported beam; no moment capacity of the connection has been taken into account in the current design. However research by the author found that even with simple steel beam to column connection, if the longitudinal steel bars are placed around the columns edge, the connection can achieve some moment capacity due to the composite action between the precast slabs and the steel beams. The behaviour of this type of connections more or less can be classified as semi-rigid connections which can be used to enhance the whole stability of the frames. Therefore, the research on the behaviour of this type of connections is quite necessary.Johnson et al.[1] firstly conducted five tests on composite connections which covered the whole range of the web slenderness available in universal beams and showed that negative moment with semi-rigid joints had greater resistance to bucking and much greater rotation capacity than rigid joints. MacGinley et al.[2] tested a series of bare steel joints and two composite connections. The two composite connections exhibited considerably more capacity than the bare steel joints. Davison et al. [3] tested eleven composite beam-to-columns connections. This was the first study in the U.K. to use relatively flexible joint details to exploit the composite floor action in composite frames. This also was the first attempt to use profiled metal decking rather than a solid slab. The test results suggested that it was unwise to rely solely on mesh to provide tensile reinforcement and that the anchorage of the reinforcement is particularly important. Seven bare steel beam-to-column equivalent joint...