2 

 A = fluke area (ft) 



c = cohesion of soil (psf) 



Y, = buoyant unit weight of soil (pcf) 



D = fluke embedment depth (ft) 



N , N = holding capacity factors 

 c q o r J 



The equation is relatively general and can be applied approximately 

 to almost any form of loading. However, the holding capacity factors 

 and the cohesion may vary with loading mode and have been found to vary 

 with soil type, density, and relative anchor embedment depth, D/B, where 

 B is the fluke width. The maj_or probl_em of estimating holding capacity 

 is then one of estimating c, N , and N . 



Before discussing methods for estimating these factors , it should 

 be noted that Equation 1 refers to square or circular flukes . In order 

 to account for rectangular flukes, the following relation derived from 

 bearing capacity equations (Skempton, 1951, Hansen, 1957, and Meyerhoff, 

 1951) is suggested: 



F^ = A (cN + y .Jm ) (0.84 + .16 B/L) (2) 



i c b q ^ ' 



where B = fluke diameter or width 



L = fluke length 



Compatible units should be used in all equations of this form. 



Cohesive Soils 



The strength of soils is generally given by the Mohr-Coulomb 

 equation: 



f 



c + N tan (3) 



where x = shear strength 



c = cohesion 



N = normal force on failure plane 



= internal friction angle 



The equation states simply that soils may be partly frictional and 

 partly cohesive in their response. With cohesionless soils (sands), 

 the behavior is strictly frictional (c = 0) , while with cohesive soils 



