penetration resistance 



vertical position 



Figure 16. Representation of an oscillograph record from a vane shear 

 test. 



In-Situ Plate Bearing Device 



The in-situ plate bearing device 32 - 33 shown in Figure 19 is used to 

 assess the short-term bearing pressure— settlement response of the near-surface 

 sediments. The device consists of a movable weight to which various sized 

 plates are attached. The movable weight is supported by three hydraulic 

 cylinders, which are metered to control the vertical displacement rate. The 

 plates can be subjected to a maximum displacement of 1 1 inches. A tripod 

 framework, used to guide the movable weight and support associated equip- 

 ment, is in turn connected to three articulated bearing pads. The equipment 

 has the capability to accommodate plate sizes up to 18 inches in diameter 

 and can apply a total plate load of 6,000 pounds. The force acting on the 

 plate during a test is monitored by a pressure-equalized electronic load 

 transducer. Plate settlement is monitored by a linear potentiometer. The 

 present depth limitation of the device is 12,000 feet — the limit of the 

 pressure housing for the acoustic telemetry system. 



31 



