Effect of building-building interaction on "free-field" ground motion

We investigate the effect induced on free-field ground motion by the interaction among buildings set in vibration by an earthquake. This is a refinement of a previous model where the building interacted with the soil, but not among each others. The waves are propagated in a multi-layered 1-d model that includes soil and a layer for each floor of the structure. We implemented numerical models in Simulink, a toolbox of MatLab, that easily allows solving the differential equations of the case. The final model is a chain of SDOF oscillators, whose dynamic behaviour depends on mass, stiffness and damping. Comparing the results with the non-interacting case, there is a reduction of the mean and median of the ground motion enhancement and an increase of the dispersion.