Total Pressure Cells

Applications

Total pressure cells measure the combined pressure of effective stress and pore-water pressure. Typical applications of total pressure cells include:

  • Monitoring total pressure exerted on a structure to verify design assumptions.
  • Determining the magnitude, distribution, and orientation of stresses.
Total Pressure Cells

Operation

Total pressure cells are formed from two circular plates of stainless steel. The edges of the plates are welded together to form a sealed cavity, which is filled with fluid. Then a pressure transducer is attached to the cell. The cell is installed with its sensitive surface in direct contact with the soil. The total pressure acting on that surface is transmitted to the fluid inside the cell and measured by the pressure transducer.

Installation

Total pressure cells are embedded in fill or mounted on structures. Infill, cells are often installed in arrays. Each cell is placed in a different orientation and covered with hand-compacted fill. On structures, the cell is typically placed into a recess so that its sensitive side is flush with the surface of the structure.

Advantages

Conformance: To minimize bridging effects, the total pressure cell has a low profile and a modulus similar to that of typical soil. Fluid in the cell is de-aired to maximize sensitivity.

Pneumatic or Vibrating Wire: The total pressure cell is available in a pneumatic or vibrating wire version.

Manual or Automatic Readout: The vibrating wire version can be read manually with a portable indicator or automatically with a data logger. The pneumatic version must be read manually.

For more information

Please download the datasheet and the manual for Total Pressure Cells. You can view and print these documents with Adobe Acrobat Reader.

Total Pressure Cells Specifications

VW PRESSURE CELLS
3.5 bar (50 psi) Pressure Cell52608220
7 bar (100 psi) Pressure Cell52608230
17 bar (250 psi) Pressure Cell52608240
35 bar (500 psi) Pressure Cell52608250
Resolution0.025% FS
Repeatability±0.5% FS
Max. Pressure150% rated range
FluidEthylene glycol, de-aired to 2 ppm
DimensionsCell is 230 mm diameter and 11 mm thick (9 x 0.43"). The transducer and connecting tube are 410 mm (16") long. Dimension from sensitive surface to connector end of transducer is 180 mm (7")
Weight3.2 kg (7 lb)
VW Jackout Cells
7 bar (100 psi) Jack-Out Cell52618230
17 bar (250 psi) Jack-Out Cell52618240
35 bar (500 psi) Jack-Out Cell52618250
SIGNAL CABLE
Polyvinyl Chloride (PVC) Cable50613824Shielded cable with four 22-gauge tinned copper conductors and polyvinyl chloride (PVC) jacket. Attached to pressure transducer at factory
Universal Terminal Box57711600Not used if pressure cells are connected to the data logger. Provides connections for 12 sensors and an indicator. Sensors selected by rotary switch. Weatherproof fiberglass box measures 290 x 345 x 135 mm (11.5 x 13.5 x 5.25")
VW READOUTS
Compatible readouts include the VW Data Recorder and other pluck-type VW readouts. See separate data sheets for details.
DATA LOGGERS
VW MiniLogger for 1 Sensor52613310
4-Channel V-Logger52615140
8-Channel V-Logger52615180
Campbell Scientific Data LoggersVW pressure transducers connect directly to the VW MiniLogger, V-Logger and Campbell Scientific CR6. Campbell Scientific CR800 or CR1000 require an AVW200 vibrating wire adapter. See separate data sheets.
PNEUMATIC PRESSURE CELLS
21 bar (300 psi) Pressure Cell51408200Pressure cell has pneumatic pressure transducer attached. Requires pneumatic tubing
21bar (300psi) Jackout Cell51418200
Range, Resolution and RepeatabilityDetermined by pressure gauge and indicator
FluidEthylene glycol, de-aired to 2 ppm
Dimensions230 mm diameter x 11mm (9 x 0.43"). The transducer adds 300 mm (11.75"). The jackout version has a transducer mounted to the center of the cell. From the sensitive surface to the connector end of the transducer measures approximately 100 mm (4")
Weight3.2 kg (7 lb)
PNEUMATIC TUBING
Twin Tubing51416900Two 4.8 mm (3/16") polyethylene tubes bundled in a polyethylene jacket. Rated for 35 bar (500 psi). Nylon tubing can be quoted on request
Splice Kit51401723Includes 3 brass unions, self-vulcanizing mastic pad, and sealing tape
Quick Connect Plug51407302Brass quick-connect fitting for input tube. The plug includes an in-line filter and 90° elbow for insertion into the panel
PNEUMATIC READOUTS
Compatible readouts include 256 pneumatic indicators. See separate data sheet for features and specifications