Experimental study on interior precast concrete beam–column connections with lap-spliced steel bars in field-cast RPC

Abstract

Reactive powder concrete (RPC) has an ultra-high bond strength with steel bars, which offers new and innovative opportunities for precast concrete structures. This experimental study aimed to develop an alternative precast interior beam–column connection for moment-resisting frames in seismic regions. A two-stage experimental program involved a series of lap-splice tests and two beam–column connection tests to assess the viability of lap-spliced steel bars in field-cast RPC (LS-RPC) used in a precast beam–column connection. In the first part of the study, the lap-splice tests were conducted to determine the minimum lap length of LS-RPC and the influences of embedment length, hoop ratio, and hoop type (rectangular or spiral). In the second part, the application of LS-RPC in the precast beam–column connection was performed to verify its reliability and its seismic performance with the expectation that this alternative precast interior beam–column connection for moment-resisting frames would be practical for application in seismic regions. It was determined that the application of highly ductile fiber-reinforced concrete in the potential plastic hinge zone could improve the seismic performance of the connection.