Hysteresis characteristics of multi-segment precast columns with ultra-high performance concrete-based grouted sleeve connections: An experimental and analytical approach

Despite the widespread use of single-segment columns with grouted sleeves, multi-segment columns with Ultra-High Performance Concrete (UHPC)-based grouted sleeve connections represent an innovative approach to enhance the adoption of prefabricated structures in seismically active areas. This study aims to assess their seismic performance through a combined experimental and analytical approach. Eight column specimens, varying by the number of segments, axial load ratios, bond conditions, and rebar diameters, were tested under quasi-static reversed cyclic lateral loading. The hysteretic curves of all specimens are plumpness, and the ductility coefficient and ultimate drift ratio are not less than 5.95 and 4.72 %, respectively, showing satisfactory seismic performance. The proposed connection strategy, integrating UHPC-based grouted sleeves, exhibited superior ductility, deformation, and energy dissipation capacities. Additionally, a hysteresis model was developed and validated with experimental data, facilitating the accurate generation of hysteresis curves for seismic analysis. The study also presents a flowchart to check shear strength for capacity protection design and obtain hysteresis curve for seismic evaluation, along with practical design recommendations.