Experimental and numerical investigation on the dynamic response of precast concrete beam-to-column connections under seismic loading

Abstract

Precast concrete beam-to-column connections play a crucial role in the seismic resilience of structures, particularly in earthquake-prone regions. The dynamic response of these connections differs significantly from monolithic cast-in-place concrete due to potential weaknesses at the joint interfaces. This study presents an experimental and numerical investigation on the seismic behavior of precast beam-to-column connections, focusing on hysteretic behavior, energy dissipation, stiffness degradation, and progressive collapse resistance. The primary objective is to assess the performance of different connection types under cyclic loading, develop and validate finite element models (FEM), and compare their accuracy against experimental results. The experimental phase involved full-scale cyclic loading tests on precast beam-to-column specimens with bolted couplers, grouted sleeves, and hybrid connections. Displacement-controlled loading was applied using hydraulic actuators, and the response was recorded using load cells, strain gauges, and digital image correlation techniques. Additionally, shake table testing was conducted to simulate real earthquake conditions. The numerical modeling was performed using ABAQUS and ANSYS, incorporating nonlinear material properties, bond-slip effects, and cyclic degradation laws. The results demonstrated a strong correlation (r = 1.00) between experimental and numerical findings, with only a 2% variation in peak load capacity. The maximum energy dissipation was 280 kN•mm (experimental) and 275 kN•mm (numerical), confirming the reliability of the simulation. Strength degradation analysis revealed that residual strength reduced to 70% (experimental) and 69% (numerical) by the tenth loading cycle. The study concludes that hybrid self-centering connections exhibit superior seismic performance, while refined finite element models can accurately predict cyclic response with minor discrepancies due to material heterogeneity. These findings contribute to optimizing seismic design strategies for precast structures and improving current modeling techniques.