Moment resistance of steel I-beam to CFT column connections

This paper focused on investigating the moment resistance of steel I-beam t o concrete-filled tube (CFT) column uniplanar connections under monotonic s tatic loading. The composite connection can be stiffened or unstiffened. An empirical formula was derived based on >100 numerical parametric analysis results. The key parameters were studied numerically by finite-element meth od and the relevant ones that affect moment resistance were captured in the proposed formula. To verify the empirical formula and understand clearly t he static behavior of the composite connections, eight specimens were desig ned and tested to failure, of which four specimens were semirigid beam-to-c olumn connections and others were rigid connections with different types of stiffening details. The comparison between the predictions and test result s showed that the empirical formula could be used to predict the moment res istance. The proposed rebar stiffener was found to be very effective in imp roving the static behavior of the composite connections.