Seismic behaviour of post-tensioned precast concrete beam–column connections

In a post-tensioned precast concrete beam–column connection, the precast beams are post-tensioned to ensure the integrity of the connection and to provide recentring characteristics when the connection is subjected to seismic loads. In this study, the post-tensioned precast concrete beam–column connections were tested under reverse-cyclic loading with the test variables of grout strength at the beam–column interface and prestressing stress of stands. The test results showed that the post-tensioned precast concrete beam–column connections have a seismic performance equivalent to that of a conventional reinforced concrete beam–column connection. When high prestress is applied, however, confinement reinforcement is required at the beam ends to secure sufficient deformation capacity without crushing of concrete. An analysis model for post-tensioned precast concrete beam–column connections is also proposed; the model considers the bond properties of prestressing strands, and provides good agreement with the experimental results.