Experiment on seismic performance of steel-encased composite beam frame

To overcome the shortcomings of common composite frame structure, a new type of frame structure system, steel-encased composite beam-steel reinforced concrete column, is presented. In order to investigate the behavior of the system, a 1 bay, 2-stories model of composite frame is designed and manufactured. The composite frame is composed of steel-encased concrete composite beams (SCCB) and steel reinforced concrete columns. The experimental study on seismic behaviors is carried out under vertical stable loads and lateral cyclic loads. The result shows that its deformation capacity, bearing capacity, ductility and energy dissipation meet the requirement for seismic design of ductile frames. SCCB frame may form a beam-hinged collapse mechanism when it is destroyed. Its effective ductility factor reaches 7.5. The seismic performance of the SCCB frames is superior to that of steel frames or reinforced concrete column-steel beam frames, so that the SCCB frames are suitable for applying to the multi-story residential buildings.