Seismic behaviors of precast ribbed concrete shear wall with shell and overlap headed bar assembled connections

Abstract

This study introduces precast ribbed concrete shear wall (PRCSW), featuring prefabricated wall panels with openings, concrete shell, and confined headed bar connections (CHBCs) at horizontal joint. The concrete shell serves as permanent formwork, expediting on-site construction. CHBCs with short overlap length connect vertical steel bars, ensuring visible on-site joint construction without grouting defects. Seismic performance evaluations through experimental tests on three shear wall specimens including one cast-in-place (CIP) and two precast specimens have been conducted. The precast specimens utilized CHBCs with single-head and double-head configurations for vertical rebar connections, demonstrating comparable flexural failure and lateral bearing capacity to the CIP specimen, with lateral capacities ranging from 298.6 kN to 310.2 kN and less than 5 % variance. Displacement ductility ratios were closely aligned (9.45–10.22), and energy dissipation patterns were consistent across different specimens. Precast specimens exhibited similar stiffness and strength degradation patterns to the CIP specimen. The precast specimens showed the equivalent seismic performances to the CIP specimen, and the presented horizontal joint was proved effective. A proposed initial stiffness prediction for PRCSW showed less than 15 % error against test data. Additionally, DIC technology was used to analyze interface behaviors, including shear and tensile characteristics between precast and post-cast concrete. Strain analysis provided insights into vertical steel bar strain distribution and stress transmission within CHBC. Configuration recommendations for the horizontal joint have also been given.