Advanced Fire Testing of a Composite Beam with Shear Tab Connections

This paper presents the results of a full-scale experimental test on a composite floor beam designed according to American codes and standards that was subjected to elevated temperatures. The test focused on the fundamental behavior and mechanics of a composite beam with end shear connections that was subjected to combined gravity loads and thermal loading, simulating realistic fire effects that included both heating and cooling. The test was conducted on a 3.80-m-long composite beam that consisted of a steel beam that was composite with a flat, lightweight concrete slab through the use of shear studs. The beam was connected to a portal frame using shear tab connections. High-temperature, ceramic, radiant heaters with independent temperature control were used to heat the steel and concrete portions of the specimen. Results from the experimental test provide insight to the behavior of composite beams and the beam-to-column connections at elevated temperatures. The composite beam and connection survived heating to 600° C, but the shear tab connection fractured during cooling.