EXPERIMENT ON SEISMIC PERFORMANCE OF NEW HYBRID-ASSEMBLING PRECAST CONCRETE SHEAR WALLS WITH VARIOUS UNBONDED LENGTHS

New hybrid-assembling precast concrete shear wall (NHPW), utilizing the combination of partially unboned of grouting-anchoring overlapping reinforcement and unbounded posttensioned connection, has the improved seismic performance by enhancing the crack resistance performance, displacement restoring capacity and yielding property. Low-frequency-cyclic loading experiments were carried out on one cast-in-situ and three NHPW specimens with different unbonded length of grout-anchored overlapping reinforcements. Compared with cast-in-situ specimen, the NHPW specimens have improved anti-cracking ability, strength and stiffness while the displacement ductility is similar, and the energy-dissipating capacity decreases. With the increase of unbounded length, the specimen's yield strength increases, the ultimate strength decreases while the anti-crack force and residual displacement remain unchanged. In general, the NHPW specimen with 150 mm unbonded length shows relatively better seismic performance.