EXPERIMENTAL INVESTIGATION OF SEISMIC PERFORMANCE OF POLYMER COMPOSITE REINFORCED AAC FACHWERK WALL SYSTEMS UNDER VIBRODYNAMIC LOADING

Abstract

This study presents an experimental investigation of the seismic performance of lightweight AAC masonry wall systems reinforced with polymer composite fachwerk profiles under vibrodynamic loading conditions. The primary objective of the research was to evaluate the dynamic behavior, stiffness characteristics, vibration stability, resonance response, and energy dissipation capacity of composite-reinforced wall systems subjected to simulated earthquake excitation. A full-scale experimental specimen consisting of AAC blocks with density class D600 integrated into a reinforced concrete frame and strengthened using polymer composite angle and sheet profiles mm was constructed and tested on a servo-hydraulic seismic vibration platform. Additional basalt mesh reinforcement was incorporated between masonry layers to improve crack resistance and structural integrity. The experimental program included harmonic seismic excitation corresponding to earthquake intensities from 5 to 9 points according to the MSK-64 scale. Dynamic response measurements were performed using high-precision accelerometers and LVDT displacement transducers. Acceleration histories, displacement responses, resonance behavior, and vibration characteristics were analyzed in both time and frequency domains. Fast Fourier Transform (FFT) analysis revealed dominant resonance frequencies near 1.99 Hz and 2.96 Hz, corresponding to the primary vibration modes of the investigated system. The polymer composite reinforcement significantly improved lateral stiffness, reduced drift response, enhanced damping capacity, and limited crack propagation during seismic excitation. The results demonstrated that the lightweight composite-reinforced wall system maintained structural integrity without catastrophic failure even under increased vibration amplitudes and near-resonance conditions. The viscoelastic behavior of the polymer matrix contributed to improved energy dissipation and suppression of excessive dynamic amplification. Compared with conventional steel reinforcement systems, the proposed polymer composite fachwerk system exhibited reduced seismic mass, superior corrosion resistance, improved deformation compatibility, and enhanced seismic efficiency. The findings of this research confirm the strong potential of polymer composite fachwerk systems for application in earthquake-resistant lightweight buildings, modular construction systems, and seismic retrofitting of masonry structures located in high seismic regions