EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF A NEW PRECAST CONCRETE BEAM TO COLUMN CONNECTION

摘要

This paper presents a study of a specific type of beam-to-column connection for precast concrete structures.Two full-scale beam-to-column connections in a precast concrete(PC)frame and a beam-to-column connection in a cast-in-place concrete structures were tested under uni-directional cyclic loading that simulated earthquake-type motions.The new-type beam-to-column joint in a precast concrete frame consisted of columns and beams.Columns could be monolithic or precast and would be connected by grout sleeves if precast.Composite concrete beams were used in the new-type joints,of which the upper parts were made of cast-in-place concrete with the floors simultaneously and the lower parts were manufactured in factories as pretensioned beams.Service hole was made in a beam end where strands were without prestress.And the unprestressed parts of strands were put into the joint core areas or the service holes of precast beams on the other side and then cast-in-situ concrete was poured to form a whole structure.Test results showed that(a)The precast connections which set the anchor head steel are similar to the cast-in-place connection seismic performance;(b)The cracking load of precast connection are similar to the cast-in-place connection;(c)The connection which set anchor head steel could achieve the purpose of enhance the ductility behavior.The results showed that the new-type beam-to-column connection in a precast concrete frame had much emergency capacity and potential in earthquake resistance compared to cast-in-place specimens.The performances of the test specimens were evaluated according to the requirements of GB 5011-2010.On the basis of the test results,design considerations for the beam-to column connection were recommended.