Help with understanding Bowles Dynamic Foundation Design

[rlewistx]

I am trying to use Joseph Bowles "Foundation Analysis and Design" 5th ed. text chapter 20 to design a machine foundation. I have some questions regarding his use of the computer program FADYNF1 supplied with the book. I would appreciate any insight into using the software.

He gives an example starting on page 1114. He runs a vertical analysis, another vertical analysis with variation of rpm, 2 sliding, 2 rocking and 1 torsional run. When he runs the vertical analysis he doesn't include any moment. When he runs the sliding analysis he doesn't include any moment. When he funs the rocking analysis he doesn't include any horizontal forces. Are these forces happening concurrent? Why is he not running some of these forces together?

Also, what do the results of the 7 runs tell us? If the sliding results do not include moments, and the rocking results do not include forces, then what does the resulting amplitude give us. Are they additive?

The last line of the output gives a YP/YS value and a YP value. Is the Yp the dynamic amplitude? What is the YS value? Why is it larger than YP?

Thanks for any insight. I wish Bowles had done a better job explaining this.