Damping effect of double friction pendulum bearings for civil buildings subjected to earthquakes considering vertical excitation forces

The authors develop a system of differential equations describing the motion of the structural system equipped with DFP bearings. The Runge-Kutta numerical method, specifically the ode15s function in MATLAB, was used to solve these equations. The results of the calculations provide a comparison of the damping efficiency of the structural system with and without the use of DFP bearings, assessing the effectiveness of vibration isolation during an earthquake, with three components X, Y, and vertical considered.