About the author:

1. Shandong Provincal Communications Planning and Design Institute Group Co., Ltd., Jinan, Shandong 250101,China; 2. School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, China;3. Southwest Municipal Engineering Design & Research Institute of China, Chengdu, Sichuan 610081,China

Abstract:

To investigate the seismic performance of prefabricated pier column,cap beam joints underdifferent axial compression ratios and shear span ratios, three specimens with varying axial compressionratios and a small shear span ratio were designed and fabricated based on a real bridge’ s three,columnbent cap. The seismic performance indicators, including hysteretic behavior, stiffness degradation,energy dissipation capacity, and displacement ductility,were analyzed and compared under low,cyclereversed loading. The results indicate that specimens under different axial compression ratios exhibitedsimilar damage progression and failure modes, demonstrating good load,bearing and deformationcapacities. Variations in axial force influenced the extent of joint cracking but did not alter the failuremode. Under high axial compression ratios, the propagation of pier column cracks toward the cover beamwas effectively controlled. Specimens with a small shear span ratio displayed pronounced shear failurecharacteristics,with joint bearing capacity approximately inversely proportional to the shear span ratio.These specimens exhibited higher equivalent stiffness,yield strength, and peak load capacity, but theirenergy dissipation capacity and efficiencywere significantly reduced, along with poorer ductility understrong seismic conditions.