Experimental study of seismic performance of weakened filled energy-dissipating steel beam-column joints

Abstract The joint performance in a routine steel frame is not sufficient to withstand the intense forces generated during a strong earthquake. A new concept for a recoverable functional building structure is presented, consisting of a packed-type energy-consumption beam-column joint that contains replaceable low-yield-point steel. That steel will fill the reduced flange parts and web parts for them and yield first during earthquakes. Once the low-yield-point steel yields, it dissipates more energy and reduces the stress transferred from the beam joints. Its increased deformation during earthquakes absorbs sufficient dynamic energy, preventing joint overload and greatly enhancing joint strength, ductility, and bearing capacity. After recovery from earthquakes, those low-yield-point steels can be replaced and re-packed again. Quasistatic loading tests were conducted on five specimen groups, including three main types: regular steel joints, those with reduced beam ends, and weakly-packed steel joints. Comparison tests showed that the packed joint type had the best energy-consumption characteristics among the three. The bearing capacity and plasticity of packed energy-consumption steel joints were better and higher than the other two joints mentioned above after the test. In addition, no failures happened even when loaded once with a full load of beam to full strength for all test specimens, even under multi-cyclic loading. The packed joints had very high resistance to deformation and sufficient ability to take in and consume a lot of energy, thus to resist earthquakes, and it could ensure both the safety and long-term use of buildings, so that buildings with such seismic resistant technologies have the advantages of cheaper, faster building constructions.