Experimental Study on Seismic Behavior of Precast Frame Column with Vertical Reinforcement Spliced by Grouted Sleeve Lapping Connector

Abstract:

In order to study the aseismic performance of the precast column connected with the new type of slurry anchor connection, a cast-in-place columns and two prefabricated column specimens, in which longitudinal reinforcement were connected by type I and III grouted sleeve lapping connector respectively, were designed for quasi-static test on the basis of the type I and III sleeve joint connection. The test phenomena show that the initial horizontal cracks of the cast-in-place column appear at the root. Because the vertical strain of the concrete is restrained by the sleeve, the initial horizontal cracks of the precast column appear on the top of the sleeve. In the limit state, the crushed part of the cast-in-place columns is long and the crushed part of the precast columns is short. The test results show that the cracking load and yield load of the precast column are slightly larger than the cast-in-place column, and the ultimate load of the precast column is higher. The cracking load, yield load of the two different types are almost the same, but the displacement under the ultimate load, ultimate displacement and ductility coefficient of the precast column are larger. Due to the stirrup encryption in the range of the sleeve of the precast column, the energy dissipation of the precast column is slightly better than the cast-in-place column. The strain of steel bar on the upper and lower parts of type I and type III sleeve is basically the same, so both of them can perform well in transferring the stress.

Key words:precast frame column; pseudo-static test; lap connection; deformation and ductility; energy dissipation capacity