Evaluation of the seismic performance of novel bundled connections precast shear walls under cyclic loading

This study proposes a novel precast shear wall connection method for connecting upper and lower wall panels. The vertical steel bars within the lower prefabricated wall panels are bundled and extended into pre-designed holes within the upper prefabricated shear walls. Subsequently, high-performance grouting materials are utilized to fill these pre-designed holes. Cyclic load tests were conducted on all full-scale specimens to evaluate the seismic performance of the proposed novel connected precast shear walls and compared with the seismic performance of the cast-in-place shear wall specimens. The findings reveal that the proposed novel precast shear wall connection method performs comparably to cast-in-situ shear walls, exhibiting almost identical results in terms of load-bearing capacity, stiffness, and ductility. Furthermore, investigations into the removal and retention of metal bellows within the prefabricated holes, as well as the effects of additional reinforcement on the top of these holes, demonstrated no significant improvement in seismic performance. Finally, the reliability of the connection method was verified by analyzing the strain changes of the vertical steel bars in the precast holes of the precast shear wall. This study can provide a reference for promoting new connections in prefabricated structures.