Recent content by kongkong

Thanks everyone. I am designing a pedestrian footbridge, so I guess 3Hz is the threshold as STrctPono mentioned. I have reviewed the modal shapes, and the first few modes seem to vibrate only part of the footbridge, so deemed not applicable. And the next few modes give...

Thanks Josh. Should I be taking the frequency with vertical direction only? Or torsional modal shape as well?

I'm designing a bridge, and need to check that the natural frequency of my structure is greater than 5 Hz. I have made 12 numbers of modes, and am getting frequencies at different modes, but have no idea how to interpret this. Do I just use the frequency at a mode where the modal load...