Evaluation of triple geofoam barrier efficiency for mitigation of ground vibrations using centrifuge modelling

Ground vibrations can adversely affect adjacent structures and sensitive equipment. Implementing wave barriers along the wave propagation path is an effective mitigation technique. While previous studies have investigated the effectiveness of geofoam as a wave barrier in single configurations, limited research has addressed the performance of multiple geofoam barriers. In this study, the vibration isolation efficiency of triple geofoam barriers is experimentally evaluated through centrifuge modelling, with results compared against previously tested single and double barrier configurations. The results show that the triple geofoam barrier system achieves vibration mitigation of up to 87.5% and improves the isolation efficiency compared to single and double barriers. It also drives the isolation system performance toward its maximum mitigation capacity and saturated behavior. Moreover, the triple geofoam barriers exhibit the most uniform screening performance across a wide frequency range, and with increasing distance from the barrier system, the isolation efficiency remains uniform behind the barriers at each loading frequency.