Humboldt HM-4160 FlexPanels - Manual (Page 20)

Fill and Drain Valves
This valve located at the bottom of each of the Control Burette Sections
and is used to fill and drain the Internal and External Burettes of the Burette
Assemblies. To Fill, the Burette or External Valves need to be open to fill that
portion of the Burette Assembly. The water to fill the Burette Assembly comes
from the Deaired Water Port on the Lower Service Connector Plate . The Burette
Assembly can not be filled unless the top is vented by turning the Selection
Valve to vent. The top does not have to be vented to drain the Burette
Assembly.
Triaxial Hydraulic Conductivity Testing Procedure
This section discusses how the equipment can be used for back pressure
saturation and consolidation of a TriaxiaI/Hydraulic Conductivity test specimen.
The steps for setting up a sample in a Triaxial Shear cell or a Hydraulic
Conductivity Cell will not be discussed.
Triaxial Cell Connection
FlexPanel Control Burette Groups are comprised of three Control Burettes,
which are labeled: Cell, Base and Top. These correspond to the Valve Ports on
Triaxial Cells labeled the same.
To connect a Triaxial Cell to the Flexpanel:
Use a length of 1/4-inch tubing to connect the Cell Quick Connect (Section 1
of a Control Burette Group) to the Cell Pressure Valve Port on the Triaxial Cell.
For a Hydraulic Conductivity Set-up, the length of the tube can be as short as 2
feet. For a Triaxial Shear Set-up, the tube should be long enough to permit the
Triaxial Cell to be placed in a load frame without disconnecting the cell pressure
line.
Two lengths of 1/8-inch tubing should be used to connected the Base (Section
2 of a Control Burette Group) and Top (Section 3 of a Control Burette Group)
Quick Connects to the corresponding Valve Ports on the Triaxial Cell.
Filling The Burette Assemblies
It is assumed that De-aired Water has been prepared following the procedure in
the De-aired Water Tank Controls Section on page 16-18.
Fill the Burette Assemblies with De-aired water by using pressure supplied by
selecting "Pressure" from the Valve in section 3 of the Master Control section or
by allowing gravity feed from the De-airing tank if it is located above the panel
board and by turning the selection valves (A1, A2, A3) to vent. Then, fill the
External Burettes for each section by turning the External Valve (E1, E2, E3) to
the external position. Turn the FiIl/Drain Valve (F1, F2, F3) slowly to allow water
to fill the external section of the Burette Assembly. Initially there will be a mixture
of air and water. Allow the External Burette to fill about 3/4 full, then turn the
Fill/Drain Valves and the External Valves (E1, E2, E3) to off.
Now, turn the Burette Valves (V1, V2, V3) to Burette. Turn the FiIl/Drain Valve (F1,
F2, F3) slowly to allow water to fill the internal section of the Burette Assembly.