Soil Testing Equipment for Permeability TestGeotest offers a wide variety of permeability and triaxial test equipment ranging from basic manual to automatic data acquisition and full computer control. These listings and descriptions present highlights and attempt to differentiate Geotest soil permeability test equipment from comparable equipment of other makes. Among these differences is the use of platens measuring 2.875", the size actually ejected from 3" thin wall tubes, instead of 2.8". Another is the use of 2,000 lbf (10Kn) capacity load frames which we believe are more than adequate for samples up to 4" (100mm) diameter. Higher capacity load frames are also offered, but generally are not needed and add extra expense.
Geotest control panels feature simplicity of operation, strong technical backup for inexperienced technicians and fast test results. Both type control panels conform to ASTM D5084 for flexible wall permeability testing and are equally suitable for triaxial compression testing in accordance with ASTM D2850 and D4767. Both have low air consumption. For that reason these panels do not include venturi type vacuum pumps which require large amounts of air to achieve relatively low vacuums. Two small vacuum pumps are offered as options. Either panel can be used to pressures as high as 300 psi (2,000kPa). Geotest systems assume one panel for each cell. This permits complete flexibility when setting all pressures. Systems using add-on panels require cells being conditioned to have identical pressures. All valves and fittings are highest quality available.
Geotest Permeability and Triaxial Cells
The permeability and triaxial cell are identical except for the top. The following features are shared:
•Standard platens are 2.875" diameter to exactly fit specimen extruded from a 3" shelby tube.
•Base and top are machined from high strength aluminum alloy, hardened and impregnated with teflon for maximum corrosion resistance.
•Chamber wall is cast acrylic of sufficient thickness to have a 10:1 safety factor for its rated capacity without need for reinforcing bands which can obstruct view and cause zones of weakness on the chamber.
• Heavy tie rods go through top of cell and screw into base forming a rigid cell frame. Positive sealing is by ‘O’ rings at the top and bottom.
•Chamber easily comes off base upon removal of tie rods due to special built-in spring releases.
•A triaxial cell can easily be converted to a permeability cell by changing the top, an operation that takes only a few seconds. We do not recommend performing permeability studies without making this conversion because latest ASTM and EPA requirements call for direct monitoring of consolidation.
•Flush through cap and pedestal permit easy de-airing by purging the pore water circuit after the sample is installed.
•Lines connecting cap to base are teflon.
•Platens are chemically inert.
•Porous stones are bronze.
•Pedestal is open to the atmosphere to permit easy access to the lower platen for any desired purpose.
•Each of the 5 base connections and 3 valves are labeled.
•All potential air pockets in the pore water circuit have been eliminated by maintaining a uniform and constant cross section from the volume change measuring systems to the specimen under test.