No / In composite steel beams with precast hollow core slabs, the amount of transverse reinforcement can have a significant effect on the shear and slip capacity of the mechanical shear connectors. The issue of connector ductility becomes especially important when partial shear connection is adopted, as premature failure of the shear connectors would lead to sudden failure of the composite beam. This chapter presents its findings on the effect of transverse reinforcement on connector ductility and proposes design equations. Transverse reinforcement is used to provide ties for the slabs and confined concrete from splitting. The ductility of the shear connector, that is, slip capacity is directly affected by the amount of transverse reinforcement. Design equations presented in this chapter for estimating the shear capacity of the headed shear stud show a good correlation with the push-off test results. For full shear connection design, pre-splitting shear capacity of the headed stud can be used for the composite design, while for partial shear connection design, post-splitting shear capacity of the headed stud should be used. In general, a minimum transverse reinforcement of T16 bars should be used if partial shear connection design is used to ensure a minimum ductility of 6mm slip.

This article reviews the design and behaviour of composite beams with precast hollow core slabs in multi-storey buildings for gravity loading. A brief history of composite construction and introduction to precast¿composite construction is given, followed by an overview of recent research work on various factors affecting the design. This includes the push-off test procedure, the load¿slip characteristic of the headed shear studs and the design procedures for this type of construction. Finite element modelling of the headed stud shear connectors and the composite beams with precast hollow core slabs are presented. Finally, recommendations and future research work is also suggested.

Use of composite steel construction with precast hollow core slabs is now popular in the UK,but the present knowledge in shear capacity of the headed shear studs for this type of composite construction is very limited. Currently, all the information is based on the results obtained from experimental push-off tests. A finite element model to simulate the behaviour of headed stud shear connection in composite beam with precast hollow core slabs is described. The model is based on finite element method and takes into account the linear and non-linear behaviour of all the materials. The model has been validated against the test results, for which the accuracy of the model used is demonstrated. Parametric studies showing the effect of the change in transverse gap size, transverse reinforcement diameter and in-situ concrete strength on the shear connection capacity are presented.

Use of composite steel construction with precast hollow core slabs is now popular in the UK, but the present knowledge in shear capacity of the headed shear studs for this type of composite construction is very limited. Currently, all the information is based on the results obtained from experimental push-off tests. A finite element model to simulate the behaviour of headed stud shear connection in composite beam with precast hollow core slabs is described. The model is based on finite element method and takes into account the linear and non-linear behaviour of all the materials. The model has been validated against the test results, for which the accuracy of the model used is demonstrated. Parametric studies showing the effect of the change in transverse gap size, transverse reinforcement diameter and in-situ concrete strength on the shear connection capacity are presented.

This paper is concerned with the behaviour of beam ¿ column connections of steel ¿ concrete composite beams with precast hollow core slabs. Experiments were carried out to investigate the joint rotation characteristics and ultimate moment capacity of these connections. Details of the test specimens, instrumentation, test set-up and test procedures are described. Results obtained for the connection moment capacity, rotation capacity and failure modes are presented. It is found that through proper design and detailing, these simple steel connections display the characteristics of a semi-rigid connection with very little extra cost.

No

This paper describes the finite element modelling of steel beams acting compositely with proprietary precast hollow core slabs. A companion paper (Lam D, Elliott KS, Nethercot DA. Experiments on composite steel beams with precast hollow core floor slabs. Proceedings of the Institution of Civil Engineers: Structures and Buildings 1999; in press [1]) reports results of full scale bending tests and compression slab tests. The finite element package ABAQUS was used to extend the scope of the experimental work, by first demonstrating that a 2-dimensional plane stress analysis is sufficiently accurate, providing that the correct material input data and shear stud characteristics obtained from isolated push-off tests are used. The FE results are within 5% of the experimental results. An extensive parametric study was carried out to investigate the flexural behaviour of composite beams with variations in transverse reinforcement ratio, stud spacing and steel UB section.

no / The recently published report on Rethinking Construction in the UK has highlighted the need to reduce on-site activities as part of its drive for greater efficiency, improved quality and greater certainty in the delivery of construction projects. For multi-storey buildings, the use of precast slabs in the floors - particularly if this can be done without the need for in-situ screeds - drastically reduces the volume of on-site concreting required. Although the use of precast hollow core slabs in steel framed buildings are common, their use in composite design with steel beams is relatively new. By designing the steel beams and precast hollow core slabs compositely, a reduction in beam size and overall floor depth can be achieved, which would lead to an overall reduction in construction cost. This paper summarises the recent developments and on-going research on composite construction with precast hollow core slabs.