Shaking table test of special concentrically braced steel frame with pinned connections for main structure of a large thermal power plant

In order to obtain the seismic performance of special concentrically braced frame with pinned connections(briefly denoted as SCBF-P),for a one-bay braced frame selected from a main plant structure of a large thermal power plant to be built in the zone with a seismic design intensity of 8 degree,a 1∶12 scale two one-bay braced frame model was constructed and tested using shaking table under 14 different earthquake ground motions.The model was designed using the same structural details as the prototype structure and connected by inter-column braces and secondary beams.The dynamic properties,responses of acceleration and displacement under different earthquakes were studied.The results show that,after intensity 8 rare earthquakes,the fundamental frequency of the test model decreased to 4.40Hz from 4.59Hz,but the columns and beams still worked well,and only a few braces and gusset plates were noticed with small out-of-plane buckling.Based on the test and FEM analysis results,the maximum story drift angles of the prototype structure under intensity 8 frequent and rare earthquakes are all less than their limit values pursuant to the GB 50011—2001 code,validating the adequate seismic performance of the SCBF-P structural system for the use in severe seismic region.