After applying a safety factor of 2.0 to t^^, determine whether 

 the load Fg^, can be applied economically for this period of time. 



1 . If it can, apply Fg^, for X^^ minutes. 



2. If it cannot, a system of breakout aids must be dfevised."^'^ 



SAMPLE PROBLEM 



An example of an application of the suggested prediction procedure 

 follows. The step identifications are identical to those of the preceding sec- 

 tion. 



Problem 



A cylindrical object weighing 50,000 pounds in water is embedded 

 in the seaf loor. A grab sample indicates that the seafloor soil is a cohesive 

 material. A submersible visiting the site reports that the axis of the cylinder 

 is parallel to the seafloor and that the cylinder is embedded to its center. The 

 cylinder is 15 feet long and 6 feet in diameter. It has been determined that 

 the object was drifting downward very slowly when it collided with the sea- 

 floor. The effort required to detach the object is to be predicted. 



= 15 X 6 = 90ft2 



= 6 ft 



= 15 ft 



= TT X 32 X 15 X 0.5 = 212 ft3 



= V3/A = 212/90 = 2.36 ft 



= 50,000 lb 



B. D/B = 0.393. Therefore, the object is partially embedded. 



C. The soil is cohesive. 



D. Assume 7^ = 30 pcf. 



E. The object was sinking slowly and the relative embedment depth 

 is greater than 0.25. Therefore, the shear strength does not need 

 to be estimated. 



30 



Solution 







A. 



1. 



A 





2. 



B 





3. 



L 





4. 



Vs 



D 

 W, 



