Unclassified 



SECURITY CLASSIFICATION OF THIS P AGE(When Da 



20. Continued 



The performance of the XSP has been evaluated in approximately 60 at-sea tests, and the 

 penetrometer has proven reliable and produces repeatable data, which compare favorably 

 with cores taken at the test sites. The water-jetting system aids penetration but does not 

 affect the data. These XSP-supplied CPT data can be used to determine soil classification, 

 relative density and friction angle in sand, and undrained shear strength in clay. They can 

 also be used in the design of foundations (especially pile design) and in bearing capacity 

 and settlement calculations. 



Library Card 



Naval Civil Engineering Laboratory 



XSP CONE PENETROMETER: A PERFORMANCE EVALUATION, 



by R. M Beard and B. A. Johnson 



TR-911 62ppillus October 1984 Unclassified 



1. Electric cone penetration 2. Cone penetrometer I. YF59. 556.091. 01. 100 



A lightweight seafloor soil test device has been developed that is capable of performing 

 in-situ cone penetration tests (CPT) to 40-foot sediment depth in up to 200-foot water depths. 

 This device, called the XSP (experimental static penetrometer), weighs 10,000 pounds and stands 

 50 feet tall. The water-jetting system, a unique feature, assists penetration to greater depths than 

 is possible with the 10,000-pound reaction force available. The performance of the XSP has been 

 evaluated in approximately 60 at-sea tests, and the penetrometer has proven reliable and produces 

 repeatable data, which compare favorably with cores taken at the test sites. The water-jetting 

 system aids penetration but does not affect the data. These XSP-supplied CPT data can be used 

 to determine soil classification, relative density and friction angle in sand, and undrained shear 

 strength in clay. They can also be used in the design of foundations (especially pile design) and 

 in bearing capacity and settlement calculations. 



Unclassified 



