3.2 COHESIONLESS SOILS 



Procedures for predicting fluke penetration in cohesionless soils 

 are not well advanced. Predictions have been made using modified 

 versions of True's method (involving the un drained shear strength of 

 the soil), but the procedures are undocumented and unverified. In 

 view of this lack of an analytical method, penetrations must be esti- 

 mated from previous data. Fortunately, the performance of the CEL 

 propellant-embedded anchors in sand is very good, and conservative 

 estimates of penetration will yield holding capacity estimates well above 

 the nominal capacities of the anchors and yet conservative with respect 

 to the available anchor performance data. Penetration estimates based 

 on the experience of the Civil Engineering Laboratory are provided in 

 Table 3-2. An assumption is made that full design charges are used in 

 the anchors. These estimates are recommended for use in predicting 

 anchor performance in the absence of actual installation experience at 

 any given site. 



Table 3-2. Propellant-Embedded Anchor Penetration Depth (D ) 

 Estimates (to Fluke Tip) in Cohesionless Soils 



Anchor 



Anchor Penetration, m (ft) in -- 



Loose 



Medium 



Dense 



Sand 



Dense 





Sand 3 



Sand C 



CEL 10K 

 sand/coral fluke 



3.8 (12.5) 



3.4 (11) 



3.1 (10) 



CEL 20K 

 sand/coral fluke 



5.2 (17) 



4.9 (16) 



4.6 (15) 



CEL 100K 

 sand/coral fluke 



7.6 (25) 



7.0 (23) 



6.4 (21) 



CEL 300K 

 universal fluke 



9.2 (30) 



8.2 (27) 



7.6 (25) 



= 30 degrees; y = 1,760 kg/m 3 (110 lb/ft 3 ) 

 = 35 degrees; y = 1,920 kg/m 3 (120 lb/ft 3 ) 

 = 40 degrees; y = 2,080 kg/m 3 (130 lb/ft 3 ) 



37 



