Appendix C 



COMPUTER PROGRAM FOR THE EVALUATION OF THE NORMALIZED 

 AMPLITUDE OF THE MAXIMUM DYNAMIC STRESS, 1 1;^^^ I 



The program evaluates the normalized amplitude of the maximum dynamic 

 stress, llmaxl' according to Equations 7, 8, 9, and 10 given in Appendix A and 

 is written for use on an IBM 1620 digital computer. A flow chart for the program 

 is given in Figure C-1, followed by the FORTRAN source program. 



Input parameters are read as follows in format (2F10.2, 2F10.8, 2F5.2, F10.8): 



4Cq<pA 

 CAY = parameter equal to « ^ = k 



w L 

 UM = parameter equal to -rj- = |i 



SFR = increment on nondimensional frequency scale. Aw' 



FMAX - maximum nondimensional frequency, wjlj^gj^ 



STU - increment on input displacement amplitude Uq , AUq 



UMAX = maximum input displacement amplitude, U- 



r r r » I 0|maX 



FZER = initial nondimensional frequency, oJq 



The computed output is presented on punched cards in the following form. The 

 values of k, jLl, j3, and I Uq are given followed by the input parameters as defined 

 above. The computed values of I ^Lgx| °''® *''^®" tabulated at each value of the 

 nondimensional frequency, according to format (E15.8, 3X, F8.4) for a particular 

 I Uq . The process is then repeated for each value of I UqI up to I UqIppq^' °^ which 

 point a new set of input data is required. 



The initial frequency is used as an input parameter in order that specific ranges 

 on the nondimensional frequency axis may be investigated; e.g., relatively small 

 increments in frequency may be used over a range of frequency corresponding to peak 

 values in | ^qxI' There is a limit to the smallest allowable increment in frequency 

 resulting from the rounding-off errors inherent to the program, which results in ^^q^ 

 equaling at co' near to 7T. These errors are discussed in the main text under 

 Discussion of Results. 



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