Experimental Investigation on the Mechanical Behavior of Semi-Rigid Composite Joints Loaded along the Minor-Axis

Abstract

Today’s design of spatial steel frames requires beam-to-column connections to be checked in the direction of the minor-axis of inertia of beam section. The mechanical behavior of minor-axis connections for bare steel joints and composite joints has been investigated by experiments. A comparison of the experimental results between the bare steel joints and composite joints shows that the mechanical behavior of the minor-axis composite joint is obviously effected by the reinforcing concrete slab, which is transversely reinforced for bending and is connected to the steel beam via shear studs, this is more in line with the mechanical behavior of the frame joint. The investigation indicates that: (1) Minor-axis joints with flush end-plate connections and seat angle with double web angles connections are all typical semi-rigid joints. The bearing capacity and the rotation ability of the joints cannot be ignored in the design. (2) Due to the composite effects of the reinforcing concrete slab, sagging moment and hogging moment must be taken into consideration when the mechanical model is established using component method.