The equation used to calculate anchor penetration in clay is: 



Q -, = A . c + A^ . c (2) 



^ult s rem F ^ ■' 



where Q = vibrator force (10 kip) 



A = total surface area of anchor shaft 



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A„ = total surface area of fluke 

 F 



c = remolded shear strength 

 rem 



c = undrained shear strength 



The penetration resistance of the shaft is calculated using the remolded 

 shear strength because the fluke has passed through the region the shaft 

 is in disturbing the soil. The fluke resistance, however, is calculated 

 using the undrained shear strength because the fluke is penetrating 

 into undisturbed soil. End bearing resistance was neglected because 

 it is neglibible compared to resistance of the shaft and fluke. Equation 2 

 takes two forms, depending on whether the anchor is fully or partially 

 embedded. For an embedment depth, D, greater than the total shaft length 

 (D> 20 feet) the equation is: 



Quit = \ • P • (^rem/p> + ^F ' P (^/P> ^^^ 



Simplifying and assuming a soil sensitivity of 2 (c/c = 2) the 

 equation is: 



^ult =[^s (° - 1°) I^ + (A, . D . y^)j 



(c/p) (4) 



For D <20 feet the governing equation is: 



Quit = a; . D . i (^) + A^ . i (c/i) (5) 



Simplifying, the equation is 



Quit = (^; • !^ + ^ • ^) ^b • ^^/p) (^) 



where A' = shaft area per foot of length 



c/p = ratio of undrained shear strength to effective vertical 

 pressure 



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