Dynamic response of damper-connected adjacent buildings under earthquake excitation

A formulation of the multi-degree of freedom equations of motion for fluid damper-connected adjacent multi-story buildings under earthquake excitation is presented. The ground acceleration due to earthquake is regarded as a stochastic process, and a pseudo-excitation algorithm in the frequency domain is implemented in a computer program to handle non-classical damping properties of the system. The 1940 El Centro earthquake time history is also used for dynamic analysis of the system in the time domain. The effectiveness of fluid joint dampers is then investigated in terms of the reduction of displacement, acceleration and shear force responses of adjacent buildings. Finally, an extensive parametric study is carried out to find optimum damper properties for adjacent buildings of different stiffness ratios and different heights. Results show that using fluid dampers to connect the adjacent buildings of different fundamental frequencies can effectively reduce earthquake-induced responses of either building if damper properties are appropriately selected.