Beam to Column Stress Transfer in Composite Structures

To clarify the mechanism of the stress transfer from the steel beam to the composite column through the beam-column joint, eight exterior beam column assemblies were tested under reversed cyclic loading with and without column axial load. The experimental variable was the ratio of the flexural strength, Ms, in the steel part of the column to the flexural strength, Mo, of the composite column. The ultimate strength and hysteretic characteristics of the joint were shown to be considerably affected by the ratio of Ms/Mo. Based on the test results on a beam-column joint with a steel beam, a rational mathematical model capable for predicting the ultimate strength of these joints was proposed. Predictions using this model were shown to be in good agreement with the test results.