A two-story building frame is modeled as shown in Fig. The girders are assumed to be rigid, and the columns have flexural rigidities El1 and El2, with negligible masses. The stiff¬ness of each column can be computed as
24Eli /hi3, i= 1, 2
For m1 = 2m, m2 = m, h1=h2= h, and Eli = El, determine the natural frequencies and mode shapes of the frame.
