8.Research on seismic performance of steel joistrestrained high-strength lightweight aggregate concrete hollow columns

Abstract:

In order to investigate the seismic performance of steel joist restrained highstrength lightweight aggregate concrete hollowcore columns under the influence of earthquakes,the low circumferential reciprocating load tests were used to investigate the effects ofaxial compression ratio,steel content of angle,angle form and width of splice plate on the seismic performance of the test columns. Theresults show that increasing the axial compression ratio can effectively improve the load carrying capacity and initial stiffness of thespecimen and reduce its stiffness degradation rate. When the axial compression ratio is 0. 55,the hysteresis loop area of the specimenis the largest and the seismic performance is the best;Increasing the steel content of the angles significantly improves the cumulative energy dissipation,but has no significant effect on the displacement ductility coefficient and stiffness degradation,and in general has asmall effect on the seismic performance;The hysteresis loop area,peak load,displacement ductility coefficient and cumulative energydissipation of the equallimbed angle specimens are higher than those of the unequallimbed angle specimens,and the specimens withequallimbed angles have better seismic performance and deformation capacity;As the width of the splice plate increases,the hysteresisloop area and displacement ductility coefficient of the specimen increase,the energy dissipation capacity increases slightly,the stiffnessdegradation slows down,and the seismic performance of the specimen with larger splice plate width is better.

Keywords: steel joist;lightweight aggregate concrete;hollow column;seismic performance