226 GDS Helpsheet - Custom Design Ring Shear Assembly
Hardware
RSA
Custom Design Ring Shear Assembly
This document explains the assembly procedure of the custom design ring shear (RINGSHSA0023)
Component description
Take the base and insert the O-rings.
If you are using a locally sourced interface plate, skip this step.
Attach the GDS-provided spacer and porous plate. These are sized to be 0.1mm under and over the nominal size in accordance with ASTM 6467-13 Section 6.4. You will notice holes have been added to the spacers to aid in the saturation and drainage of the sample
Only complete this step if using a locally sourced interface plate.
Attach locally sourced interface to pedestal, ensure the outer and inner dimensions are 0.1mm smaller and larger than the nominal sizes respectively.
Insert grub-screws with nylon tips to the pedestal. These are for the confining rings, 3 OFF per ring. Adjust the grub-screws to the correct height, this can be done by either; using a straight edge across the porous plate or interface plate.
You can also can use a Vernier Caliper to set the required height.
Attach confining rings to top cap using 6 OFF bolts (3 OFF per ring), ensure confining rings are sat inside the machined recesses. This is so that we can get the correct concentricity between parts.
Place top cap assembly onto pedestal assembly so that parts can be aligned concentrically to one another.
Insert 6 OFF Screws in 3 positions on each confining ring (3 OFF per ring) and clamp confining rings in place. The grubscrews will have been set to the correct height so the screws from the bottom are to ensure the confining rings don’t move whilst preparing your sample.
Remove the screws from the top plate that are holding the confining rings in place, then remove the top plate from the assembly so you are left with the below.
Insert sample to a height of 30mm or as required depending on interface heights.
Add Perspex wall to the base. The O-ring will be left in place between tests.
If using a locally sourced interface plate, skip this step.
Attach GDS-provided spacer and porous disc to top plate.
Only complete this step if using a locally sourced interface plate. Attach either another interface plate or a locally sourced spacer, with dimensions the same as the interface plate, to the top plate.
Place assembled top plate onto the lower assembly. Ensure confining rings sit inside the machined recesses in the top plate.
Bolt confining rings to the top plate.
Insert adjustment bolts around the edge of the assembly, to clamp the sample into place for safe transport of the sample. The fully threaded bolts can be left in the top plate between tests to save completely unwinding them from the system.
Place clamped sample assembly onto the sample table provided, this step can be done at any time during the process. The sample table can be bolted to a bench or left free-standing.
Remove the lower bolts and grubscrews holding the confining rings in place, use the slot in the sample table to assist.
Replace the bolts and grubscrews with the sealing plugs provided, ensure the O-ring is placed on the plug before insertion.
Once all the plugs are in place remove them from the sample table and carefully insert them into the machine. Ensuring the vertical actuator is fully retracted so there is space for insertion.
Carefully move the vertical actuator down until the load cell adaptor bottoms out inside the load cell connector, see the image below for clarity.
This is done before bolting down the assembly to ensure concentricity is kept between the sample and the load cell.
Step 19: Bolt sample assembly down to adaptor keeping adjustment bolts in place to ensure everything stays secure and concentric.
Remove/retract adjustment bolts so that the tests can be run. You are now ready to start the test.