NUMERICAL ANALYSIS OF INNOVATIVE PRECAST CONCRETE COLUMN MORTISE-TENON SPLICE UNDER LATERAL LOAD

Abstract

A previous shaking table test of an 8-story miniature precast concrete moment frame building with non-emulative dowel-based connections yielded favorable results. To upscale these connections, a mortise-tenon concept using a concrete-filled steel pipe has been proposed to replace the dowels in column splices. Although a design procedure has been developed, further numerical analysis is required to confirm it and to predict the experimental behavior. This study presents the first numerical investigation of this connection type and serves as a pre-experimental analysis to guide future experimental studies. This study focuses on finite element analysis of a 450 mm × 450 mm × 3000 mm cantilever precast concrete column with a mortise-tenon splice utilizing a Ø130 mm × 20 mm × 1200 mm concrete-filled steel pipe under monotonic lateral loading, compared with a monolithic column. The pipe centroid is located at 1 m from the fixed base, coinciding with the column segment interface. Results show that the precast column has a similar load-displacement curve shape to the monolithic column but with reduced capacity due to localized stress at the connection interface. At a 25 mm top column displacement, the precast column achieves 88.28 kN lateral capacity and 25,600 kNm/rad secant rotational stiffness at the connection. The design procedure yields a conservative factored capacity of 60.95 kN (69% of finite element analysis results), confirming its suitability for proportioning test specimens. The observed concentrated damage at the connection emphasizes the need for further full-scale cyclic experimental validation for seismic design recommendations.