Ductility of Profiled Composite Beams. Part I: Experimental Study

A series of experiments on profiled composite beams is reported. The experiments include two profiled composite beams and two reinforced concrete beams that were previously tested under sustained service loads. The tests reported were used to ascertain the flexural strength of the beams and to validate the hypotheses of the previously reported service-load tests. Companion specimens of concrete cylinders were tested for compressive strength and elastic modulus properties, for both sealed and unsealed conditions. Specimens of profiled steel-sheeting coupons and reinforcing steel bars were tested in tension to ascertain their yield stress and elastic modulus. The tests here are shown to verify the previously mentioned hypotheses and to provide benchmark results used to validate the theoretical predictions of a companion paper. Failure is shown to occur progressively through a combination of bond-slip failure and local buckling of the steel sheeting. The tests are then used to calibrate a theoretical model for the cross-sectional behavior of profiled composite beams. Local buckling was observed and is predicted by the use of a finite-strip method developed elsewhere.