The use of the table Is as follows. Column 1 consists of the amplitudes of the 

 cable support-point oscillations as selected above, and from this. Column 2 may be 

 calculated by multiplying by k derived previously. Column 3 is computed for the 

 given L, Ij, |Uq|, and E values appertaining to the cable. For polypropylene or 

 nylon cables, it may not be possible to determine Ij and E directly. Manufacturers' 

 tables generally allow the computation of S I^j and S E, where S is the material cross 

 section of the cable. Hence, the constant ratio ^^j/E may be determined and used in 

 Column 3. 



Column 4 Is obtained from the curves of Figures 2 to 7, 8 to 13, 15 to 22, and 

 25 to 32 for the particular values of fi and j3 given in the table. Column 5 is eval- 

 uated from Column 4 for the particular ratio of c/L^ . Thus, from Columns 1 and 5 a 

 curve relating the allowable amplitude of oscillation to the frequency of that oscilla- 

 tion may be drawn for the particular cable length used. The process may then be 

 repeated for other cable lengths. A judicious choice of cable length can serve to 

 reduce the numerical calculation to a minimum. 



It may be assumed that operating conditions lying on or below the curve are 

 safe, with the safety factor, F, as defined, and that operating conditions lying above, 

 to the right of, the curve are unsafe. 



In line with comments raised in the Discussion of Results, the unknown parameters 

 are Cq and C^. With existing deficiencies in data giving Cq and C^^ for various load 

 configurations, they must of necessity be estimated. See Appendixes D and E. 



If it should occur in a design problem that the ranges of co', jS, or pi are not 

 covered in the graphs developed in this study, then the appropriate curves may be 

 calculated for specific values, or ranges of values, of those parameters by use of 

 the digital computer program used in obtaining the results quoted herein. Details 

 of this program are given in Appendix C. 



Two examples of the application of the above design procedure are given below. 



APPLICATION OF PROPOSED DESIGN PROCEDURE TO TWO PROTOTYPE 

 EXAMPLES 



The application of the proposed design procedure to two hypothetical prototype 

 examples Is demonstrated below for polypropylene and steel cable respectively. The 

 parameters used in these examples are such as to enable the design procedure to be 

 carried out using the curves presented previously in the results. 



Design Example Using Polypropylene Cable 



The parameters of the load are given as 

 M = 5.0 tons = 10,000 lb 

 A = 12 ft X 12 ft = 144 ft2 



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