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...�..:t:•� «.,...u-.�u�rn,�. -_—. �•�.:��c. �.��;.�� Vis.=-,.r - == � �iw .� �-::;. arae, r .`--��"rxr-vas:., � $•=,��,�r_� .. �-�3,. r R-VALUE TEST PAPER BASKET MATERIAL Col:fornia Test 301 1978 T-INTERLOCK rINTERLOCK SLOT 16 SLOTS AT :'SPACING / SLOT -;v ..fa n.Io T n- it! t — `x 132 t•IGURE 3 3. Place well raised samplc in compactor feeder 9. if five water should appear arouird the bottom trough with the loose materiai distributed evenly of tite maid during compaction,stop the compactor along the full length, immediat,ly anJ note the number of tamps by con- 4. Start compactor and adjust the air pressure to 15 version Of the (lapsed time. psi which is about 240 psi foot pressure,Wait until the 10. If Ilse surface is left.ineven by the action of the foot reaches its lowest position before putting any tarttping f00t, smooth and level the tamped surface material in the mold.Operate compactor in accord- with a 1 y,to 2 inch diameter fiat ended compaction ance with instructions for operation and calibration rod using a geode tamping. of themechanicalcompactor (California Test 101), F'rococl re ,ehen baskets erre regtrrnci. 5. Using spatula formed to fit the feeder trough, U. Coarse granular materials are usually very dif• hush the material in the lower 3 inches of the trough f;cult to process without tenial a to the specry di - into the mold to corer the bottom.Push the remain- trod require the use of a paper basket t to keep the der of the sample into the mold in 20 equal parts specimen intact.Baskets prevent the specimen from using one part of for each blow of the compactor, falling out of the mold and minimize disruption or (1�figure 4.) .Mow 10 additional blows to level and set g 1 the material. Raise and clean compactor foot. Place crumbling during processing through the various rubber disc,315/6-inch diameter,14-hich thick,on top stages of I lie R-v;duc procedure. of specimen, (During the feeding operation, if the 12. All standard graded Uass 1 and Class 2 aggre- soil pushes up around the foot markedly,lower the gate bases must be compacted in haskets. Baskets air pressure below 15 psi to a pressure which will may also be needed for other materials (e.g.Class 3 reduce the pushing up). a grenate bases :utd aggregate subbases) where 6. Loosen the mold in the molt; holder by backing coarse agg'egates or clean sands are invok-ed (see off the thumb screw clamp, lower compactor foot notes). and immediately increase air pressure to the calibra- tion gauge reading required to obtain a compactor foot pressure of 350 psi which is usually 21 psi air Pressure on the gauge. Ott compactors that are so equipped, the green indicator light wiil flash on when a pressure of 335 psi is reached. 7. Clays may require Inwer compaction pressures due to escc5.ive penetration of the compactor foot '; •Y ' into the tc%: slrcc'imen at 350 psi pressure. 1u thes( cases rout perr nation and not pressure becomes the controlling,L:- for 11---duce the foot pressure to where tilt:compactor foot penetrates not more than %,-inch into the surf:!.e of the specimen.Record the reduced -------------coil)pactic"-pressttrxs. —p ---�� --- - S. Apply f(i0 tatniis to tltc spccitn(n using either � ' •,�`t ------------------ ------------- -- 350 psi foot pressure or the foot penetration criterion, whichever governs in the individual cases. FIGURE 4 7