Development of Precast Concrete Members with Non-contact Lap Spliced Longitudinal Bars Encased in Grouted Corrugated Ducts

Abstract

Recently, precast reinforced concrete construction methods are considered for implementation in Southeast Asian countries to ensure high quality and increase speed of construction. Instead of using costly grouted steel sleeves for connecting precast column longitudinal bars, a construction method using non-contact bar splicing inside grouted corrugated ducts with additional tie reinforcement along the bars’ splicing length was developed. A seismic test of a cast-in-place column without lap-splice and precast columns with a lap splice length 40 times the bar diameter was carried out without an axial loading. Test results showed that the strength of the precast columns exceeded the calculated value by ACI code, and the attained ductility was adequate. Moreover, initial stiffnesses and shear strengths were larger for the non-contact lap spliced specimens than for the specimen without lap splices. The results of the precast column with lap splices and the cast-in-place column without lap-splices showed no difference in terms of shear strength, hysteresis behavior and ductility.