Grouts and Grout tests for NOVA

1. Grouts and Grout tests for NOVA • The NOVA extrusions, when filled, will exert an average pressure of 19 psi (2736 psf) on the floor. • The pressure is not uniform: Grout test study results Hans Jostlein

2. Floor pressure • It is actually more complicated; there is partial force transmission through the webs, • Except for the middle channel in the end cap. Grout test study results Hans Jostlein

3. There are two locations where grout can even out the pressure on the Extrusions: • Between the block and the pallet (applies to IPND as well) • Between the pallet and the hall floor (Applies to far detector only) Grout test study results Hans Jostlein

4. Why do we need grout ? • The PVC block is stiff • We always assumed a full support area • There are several sources of imperfect alignment of the block components versus the pallet- or floor shape: Grout test study results Hans Jostlein

5. Geometrical Imperfections • Non-square module bottoms (X and Y) • Module bottoms misaligned (X and Y) • Pallet construction tolerances • Concrete floor not a perfect plane Cumulative error: Somewhere between 1/16” and 1/8” (my own wild guess) Risk: High Stress Points on the bottom glue joint may cause glue joint failure Grout test study results Hans Jostlein

6. Grout Requirements • Long Service Life (no deterioration with time or oil soaking) • No Creep (to avoid stresses during partial oil filling) • Stiff (same reason) • Easy to install • Must flow easily • Must provide very long pot life (Days ?) • Must bear loads quickly (an hour or less ?) • Does not require a tight seal to prevent leak-out • Inexpensive (if possible) Grout test study results Hans Jostlein

7. Liquid Organic Grouts • Commonly used for machinery • Require leak-tight form • Not easily used on far detector floor • Load bearing setup time is much longer than the pot life • Costly Grout test study results Hans Jostlein

8. Cement based grouts • See DocDB # 581 (January 2006) for measurements • Last for decades (centuries ?) • Do not require leak tight forms • Have the marvelous property of being Tixotropic: • Behave like liquids when shaken or stirred • Behave like solids when at rest Grout test study results Hans Jostlein

9. Typical mix • Use “play-sand” as filler, add cement, mix • Or, use premix, add water, and mix • Fill into the gap • “vibrate” with a long board until settled • It can now bear the full load instantly • Let cure (curing can be as short as 30 minutes, and can be tuned with additive for a “pot life” as long as 3 days) Grout test study results Hans Jostlein

10. Test assembly Grout test study results Hans Jostlein

11. Purpose of the Test • Find out how hard or easy it is to fill the mortar in a tall gap with realistic block shape • Check on resulting completeness and distribution of fill • We covered the plywood wall with plastic foil to separate it from the mortar Grout test study results Hans Jostlein

12. Test Progress • Everything worked pretty well on first try, • Except we tried to vibrate the mortar with a ¼” stick, which was too wimpy • On second try, used a 4” x 1/8” x 4 ft G10 strip, • Which made the mortar flow perfectly Grout test study results Hans Jostlein

13. Grout test study results Hans Jostlein

14. Grout test study results Hans Jostlein

15. First try– not quite perfect Grout test study results Hans Jostlein

16. Second try—perfect matching to the plywood/ foil wall Grout test study results Hans Jostlein

17. Floor Grouting (Far Detector only) • Place mortar on floor over the whole contact area • Use a rake-type (maybe vibrating) tool to groove it deeply • Set the block down with the block raiser • During block alignment there is enough motion to re-liquefy the grout • If not, just make a very small motion with the block raiser and set the block down • Grout will set to full load bearing strength as soon as the motion stops Grout test study results Hans Jostlein

18. Floor Grout Test • In Lab F (thanks, John Voirin !) we set a stack of three steel blocks on a grout bed • The three blocks exerts the same floor pressure as the far detector • We tested freshly mixed grout and day-old grout with Eucerin retarder mixed in • We covered floor and top of mortar with a PE sheet for easy inspection and clean-up • We installed 4 dial gauges to measure distance from floor to check for sagging Grout test study results Hans Jostlein

19. Sand mortar grout, shaped with a trowel Grout test study results Hans Jostlein

20. First block loaded onto grout bed, and equipped with dial gauges Grout test study results Hans Jostlein

21. Three blocks loaded. Droop motion is less than 10 mil Grout test study results Hans Jostlein

22. Grout after 3-day loading ; Middle is raised, matching bottom profile of the steel block Grout test study results Hans Jostlein

23. Grout with retarder, before loading Grout test study results Hans Jostlein

24. Grout after 3 days Grout test study results Hans Jostlein

25. Future • Would like to use it on the mechanical prototype of the INPD • Would like to use it on the FHEP (to test floor grouting, mostly) Grout test study results Hans Jostlein

26. Reference For earlier detailed emasurements on grout compressibility and load behavior see: NOVA Document 581-v1 Grout test study results Hans Jostlein