Run some Computer Simulations.

Using the URL: http://weaveserve.egr.duke.edu:8080/weave/modules/sim1/ run some Matlab simulations. In all numerical simulations the floor mass is kg.

1. First run a sine-sweep test from Flo = 1 Hz to Fhi = 10 Hz with N/m and N/m/s (the default values). When the plot appears, use your mouse to zoom-in on the portions of the response with large amplitude. Count the number of oscillations in the response over a given period of time and estimate the natural frequency in radians per second. Do these values agree with the predictions given by Figure 6?
2. Now with the same value of damping N/m/s, run three more simulations with a more narrow range for the input frequency, focusing on the three natural frequencies one at a time. Do you see beats in the response? For each of these three simulations estimate the peak response amplitudes for each floor. These should be almost proportional to the mode-shapes given in Table 1.
3. Run two more simulations this time varying the damping using values of N/m/s and N/m/s and with frequencies from 1 Hz to 10 Hz. How does change in damping affect the amplitude of the response? Do the amplitudes change in proportion to the change in damping?