Attached to the lower end of the push rods is the cone unit 

 (Figure 3). The cone unit contains the jetting nozzle, upper sounding 

 rod, jetting friction sleeve, lower sounding rod, and the electric 

 penetrometer tip. This tip consists of a cone and a friction sleeve. 

 The XSP penetrometer tip is a 5-ton Fugro Wison Cone. 



The jetting nozzle will be discussed in more detail in the section 

 entitled Water Jetting System . Basically, water is pumped through the 

 push rods and out the jetting nozzle. The water coming out the jetting 

 nozzle is aimed back up the outside of the push rods to fluidize the 

 soil and ease penetration of the push rods. 



The upper sounding rod is a watertight structural connection 

 between the jetting nozzle and jetting friction sleeve and it creates a 

 separation between the waterjets and jetting friction sleeve. This 

 sleeve is a strain-gaged section used to measure differences in the 

 friction caused by the jetting water near the jets and the friction at 

 the friction sleeve on the electric penetrometer tip. 



The lower sounding rod is both a structural connection and separa- 

 tor between the jetting friction sleeve and the electric penetrometer 

 tip. In the penetrometer tip, strain gages are used to measure pressure 

 on the cone and friction on the sleeve 3 inches above the cone. The 

 signals from the cone and the friction sleeve are amplified and trans- 

 mitted up the cone cable and ultimately to the surface instrumentation 

 console. 



Instrumentation Console 



The instrumentation console (Figure 4) contains the controls for 

 the XSP, monitors the sounding process, and records the data. This 

 console, about 4 feet tall and 2 feet square, is housed in a fiberglass 

 case. A power cable connects the console to a 208-volt, 3-phase AC, 

 30-ampere power source. The console is, in turn, connected to the 

 junction box on the XSP's base by an underwater umbilical cable. From 

 the junction box, cables lead to the motor, depth encoder, and the cone 

 unit. The console also has readouts for two electronic pendulums 

 located inside the junction box. The pendulums detect structure tilt in 

 two vertical planes rotated 90 degrees from each other. Signals from 

 these devices on the XSP are amplified and scaled for output to the 

 panel meters and recorder. The major control on the console is an 

 UP-STOP-DOWN switch for the driving mechanism and the cone penetrometer. 

 There are digital readouts for the cone pressure, cone pressure and 

 friction sleeve, friction sleeve, jetting friction sleeve, and depth of 

 soil penetration. Electronically, the cone and friction are measured 

 together and then the cone is subtracted to display the friction. Other 

 gages provide readouts for the manually controlled 24-hour clock, tilt 

 gages, a voltmeter, and an ammeter. The cone pressure, cone friction 

 sleeve, and jetting friction sleeve are recorded on a Watanabe strip 

 chart recorder as a function of depth. 



