2. Determine Soil Type . Determine the general soil type (cohesive 

 or cohesionless) . This will be obvious from the visual observation of a 

 bottom sample, even a very disturbed grab-type sample. In areas far 

 from shore, it may be possible to estimate the bottom type given a 

 chart of the regional geology. In addition, good geophysical data, if 

 available, may give clues. If at all possible, however, a bottom 

 sample should be obtained. 



3. Determine Short-Term Holding Capacity for Cohesive Soil . Steps 

 3 through 5 assume the soil has been determined to be cohesive. The 

 procedure to be followed in estimating the short-term holding capacity 

 depends upon whether or not good quality cores or in-situ strength data 

 have been obtained or a field test has been performed. 



Core or in-situ data available . If reliable engineering properties 

 are available, the procedure is as follows: 



(a) Plots of the undralned or vane shear strength and unit weight 

 distributions should be developed. If the strength and density are 

 approximately uniform with depth, then the characteristic strength, c, 

 and characteristic density, Y,, are simply the mean values over the 

 depth range, D. If the strength increases approximately linearly with 

 depth from a value of near zero at the seafloor surface, then the plots 

 of Figure 7 should be used to obtain the characteristic strength and 

 density. This is done by first calculating D/B and talcing the strength, 

 c , at depth, D, from the strength profile. Figure 7 is entered with 

 these values and the quantity D /B is determined. The characteristic 

 strength, c, and density are then taken as the strength and density a 

 distance, D , above the anchor fluke. For more unusual strength and 

 density profiles, either a conservative uniform or linearly increasing 

 curve should be drawn through the data or an experienced seafloor soils 

 engineer should be consulted. 



(b) Given D/B and c, the parameter N is obtained either from 

 Figure 2 or Equation 5. 



(c) The short-term holding capacity is calculated from Equation 4. 



Soil data unavailable . If strength and density profiles are not 

 measured, then the profiles of Figure 6 should be used and Steps 3a 

 through 3c repeated. This procedure may be simplified by using Figure 9 

 and obtaining holding capacity, F , directly. It should be noted that 

 in almost all cases, this procedure will yield unnecessarily conservative 

 holding capacities. If at all possible, strength and densities for the 

 design location should be measured. 



Field test . In some research and practical situations, it may be 



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