No belting broke as a ressult of mooring loads. The Goodyear samples broke when an 

 attempt was made to pull the moorings out by pulling vertically on the rubber chain. 



The tensile test specimeas were cut according to the diagram shown in Figure 1. A three- 

 inch gauge length was used in all the tests as reference. A steel scale was fixed to the top 

 part of the specimen in order to measure deflection. 



TTie load deflection curves obtained are shown in Figures 11 through 13, with the data 

 sheets shown In Figures 14, 15 and 16 and the failure loads shown in Figure 17. The third 

 column shown in Figure 17 is used to show the relative strengths of each belt on a pound 

 per inch of width basis, and is obtained by dividing the failure load of each belt by the 

 average width in the three-inch gauge length. Note that the thinnest belt is not 

 necessarily the weakest. 



In the case of the Uniroyal Royalon and Empire State samples, the thickest rubber cover 

 was still taking load, even though the base fabric and the thin rubber cover had both 

 failed. Neither sample was able to be stretched to total failure. The Uniroyal sample was 

 holding 290 pounds when the gauge marks were 5-1/2" apart and the Empire State sample 

 was holding 100 pounds with the gauge marks at the same distance apart. 



All three load deflection curves have a similar shape. The curves provide an indication of 

 the stiffness of the belt, i.e., the amount of deflection the belt allows for a given loading. 

 An inspection of the curves shows that Goodyear allows the mos?t deflection. 



The elongation ranged in value from approximately 17% for Goodyear and Uniroyal 

 Royalon to 14% for Empire State. The significance of these numbers lies in the fact that 

 the tensile tests tested the synthetic carcass fabric rather than the rubber covers. The 

 possibility exists that without stripping away the external rubber covers, the jaws of the 

 tensile test machine will bite into the rubber only, and as the strength of the bond 

 between rubber and carcass is exceeded, allowing movement between them, the deflection 

 measurements become a function of the rubber only, not the entire belt. However, since 



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