izax1,
Im not sure I agree with you...I think what Steinberg says is that for one resonance peak you can assume the positive crossings per sec is simply the resonance frequency, but I dont think there is anything in the post-process of problem 8.20 which is limited to single resonance.
The...
Hi dylan1450,
If I am not mistaken the Steinberg reference assumes a gaussian distribution and hence the different probabality from each environment is taken into account as follows:
The sigma 1 RMS stress ocurrs 68.3% of the time, thus the total number of cycles is equal to .683 X (total time...
I still dont get it...if I calculate the RMS stress from an output PSD (obtained from the transfer function and the input PSD of a random vibration test), why cant I just go to standard S-N data for R=-1 and apply miners rule for sigma 1, 2, and 3 with the cycles calculated from the positive...
If your dealing with relatively thick laminates you might want to consider a step or scarf joint, as far as I know its the best way at reducing stress concentrations and preventing delamination at run-out plies. I cant think of any reason at all why an overlapped joint would be advantageous...