Russell Q. Bridge

Partial shear connection design of composite slabs

Abstract A new partial shear connection strength model has been developed which considers the equilibrium of a segment of a simply-supported composite slab under any loading condition. The model incorporates shear connection performance derived from a new test called the slip block test. This small-scale test shows that shear connection performance is affected by factors such as profile geometry, base metal thickness and concrete compressive strength. Full-scale slab tests have proved that it is a reliable physical model which can readily account for the effects of changes in shear connection performance, loading pattern, sheeting end support conditions, end anchorage devices, conventional reinforcement etc., and is being developed for possible use in an Australian Standard on the design of composite slabs. The ease with which the model can be used in design is demonstrated in a worked example. Another new ultimate strength method of design, published by the Steel Deck Institute in America, is examined in the worked example, and shown to give erratic, sometimes overly conservative but often very unsafe predictions for the particular profiled sheet and design situations studied.

Reinforcing against Rib Shearing Failure in Composite Edge Beams

Brittle rib shearing failure comprises horizontal splits that form in the concrete between the tops of the steel sheeting ribs in pans where there are shear connectors, while the failure surface locally avoids the studs by passing over their heads. It has been reported in the literature to have often occurred in push-out and beam tests. It is now mandatory in Australian Standard AS 2327, Part 1 to reinforce composite edge beams against rib shearing failure. A patented reinforcing component has been developed for this purpose.

Design of composite columns : steel, concrete or composite approach?

Composite columns are a combination of two traditional structural forms: structural steel and structural concrete. As composite columns were generally developed after steel columns and reinforced concrete columns, their design approach could have been based on either steel or concrete design methods. However, steel column design methods have differed from concrete design methods in a number of fundamental ways. Despite this, either design approach can be used as the basis for developing a design method for composite columns and this can be seen in the different methods currently used in Europe and the USA for composite columns. While the design approaches appear fundamentally different, the end results can be surprisingly similar. By understanding the design philosophies, designers can take full advantage of each approach for the effective use and economy of composite columns.

The Integration of Partial Shear Connection into Composite Steel-Concrete Design Procedures

The design of composite beams using rational partial shear connection theory is well established and has been included in design codes such as Eurocode 4 (1) and the more recent Australian Standard AS 2327.1-1996 (2). However, the design of composite slabs has previously been based on empirical methods. Australian steel decking profiles exhibit strong and ductile shear connection to the concrete slab and can be designed using partial shear connection theory in a similar manner to beams, thereby providing a rational design approach to flexural members.