Seismic Performance Of Innovative PEC Column-Steel Beam Composite Frame With Frictional Energy-dissipation Connection

New type PEC column(partially encased concrete composite column)generally consists of H-shape steel section or thin-wall composite section with links(for non-curling)or laths(for curling)welded and concrete casted between opposing flanges.The study showed that new type PEC column has high strength and lateral stiffness etc favourable seismic performance.Up to date,most research on PEC colum-steel beam is focused on the sesismic performance of artifacts,connection and layers.And less on the research achievements of structure of the overall level.Therefore studying its seismic performance on the overall level will be of significance.The two story-one bay substructure of innovative PEC column-steel beam composite frame with friciongal energy-dissipation t-stub connection was tahen as a research subject.On the laboratory conditions of loading equipment,a 1/2 scale test specimen was designed and conducted under cyclic loading to study its seismic performance.Based on the analysis data of test and the specimen’s seismic performance observed were analyzed,including the capacity,degradation of lateral stiffness,joint connection performance,failure mode ect.The software ABAQUS was adopted to simulate the test specimen and validate its feasibility.And further analyzed on the influence of vertical force.Acoording to the data of the experimece and simulation,The results indicated that the specimen has the high strength and lateral-resisting stiffness.The lateral stiffness is evenly distributed along the height of the specimen due to the energy-dissipation capacity of second storey is slightly bigger than first storey.The energy dissipation capacity is provided by friction,steel yielding and concrete crushing at bottom of PEC column and steel yielding steel beam section near the end bolt of split-tee web,and the design target as earthquake energy is dissipated by friction at frequently occurring earthquake and yielding of principal members at design-base or maximum considered earthquake for frictional energy-dissipation T-stub connection is achieved.The failure mechanism primary induced by plastic hinge formed in steel beam section near the end bolt of split-tee web and the bottom of the PEC column,the corresponding inter-story drift rotations and connection rotations all surpassed the inter-story drift limit(1/30)of frame structure under maximum earthquake,it induced that the specimen owns sound seismic ductility.