EXPERIMENTAL INVESTIGATIONS OF COLD-FORMED JOINTS FOR MULTI-STOREY STEEL FRAMED STRUCTURES

This paper investigates the behaviour of back-to back cold formed C beams-to-SHS column joints under monotonic and cyclic loading. An experimental program was carried out in order to evaluate the structural performance of such joints in cold formed low rise multi-story steel framed structures. Two different configurations of joining a double C section beam with a square hollow section column have been tested experimentally. The first type consists of two flange diaphragms welded to the column which are fixed to the beam's flanges through 4 x M20 bolts each. The second joint configuration has T-stubs placed at the upper and lower flanges of the beam, each of them being fixed through 4 x M20 bolts by the column and 4 x M20 bolts by the beam's flange. The behaviour and failure mechanisms of joints have been observed experimentally, their stiffness, strength and ductility have been evaluated based on experimental studies. The test results provide essential data for the validation of detailed numerical and analytical studies which can be employed for further assessment of the response, with a view to the development of design-oriented procedures. Using the experimental results, finite element models were built and calibrated to evaluate mechanical responses of the analysed joints. Preliminary results shows good agreement between analytical and experimental results.