This relationship was obtained by trial and error to minimize the 

 points falling outside the band of the relationship plus or minus one-half log 

 cycle of T. Equation 6 is plotted in Figure 4 along with the band designating 

 plus or minus one-half log cycle of T. This band contains 70% of the data 

 points. 



^ \l 



\ 



1 





1 



1 



1 1 



\o \ 



\ 



o 











\ A 



\ 











O San Francisco Bay field tests 



\ \ 





\ 











Q \ \ 



V 



\ 









H Gulf of Mexico field tests 



_ \ 

 \ 



\ 



\ 

 \ 









O FY-68 laboratory tests ~ 



\ 

 \ 

 \ 



^ 



\ 









» » Indicates test discontinued 



\ 



^ Y \ 



\ \ O 



ON O' \ 



\ 





Q 



before breakout 



Dashed-line band represents _ 

 Equation 7 plus or minus 





o 



\ \ 



\ 







one-half log cycle of 



o 





\q\ 



Q^ 



\ 





normalized time 



^ G 





<^|'\ 



\ 



\ 













N 



N 

 N 































-^. 



1 





1 



-B^ 



1 



1 



1 1 



Normalized Breakout Time, T 



P'b/BV 



Hog scale) 



Figure 5. Relative force versus normalized breakout time — long-term field 

 tests and FY-68 long-term laboratory tests. 



By using Equation 6 as a guide, a similar relationship was developed 

 for the field test data: 



loQio T~ = -0.193(10910 T - 3.84) 



""lb 



(7) 



The same criterion was used to obtain this equation as was used for 

 Equation 6. Equation 7 is plotted in Figure 5 along with the band designating 

 plus or minus one-half log cycle of T. This band contains 53% of the data points. 

 Only 13% of the points fall to the right (unconservative) side of the band. 



24 



