"Response" is what an object, living or nonliving, gives to a certain situation. It can be passive response or active response but it doesn't matter. What matters is how the buildings respond to earthquakes. Let us say for an example, you take a pendulum and you pull it to a certain height and leave it for free oscillation. What you will see is the mass attached at the end of the pendulum moving back and forth constantly, such motion is simple to understand as it is clearly visible to your eyes. The time a pendulum takes to complete one oscillation is called the time period of a pendulum. This factor, "time period" is very important characteristic of a building, it can tell you everything about the building, every ins and outs. Coming back to pendulum and time period, when you plot the motion of pendulum with respect to time it will give you a sinusoidal curve called the response of the pendulum to the disturbance. It will look something like this: Angl...
Structural Engineering and Structural Mechanics Blog. Carry on the Madness