MAXIMUM DRY DENSITY OF THE SOIL AT OPTIMUM WATER CONTENT BY STANDARD PROCTOR COMPACTION METHOD.
PURPOSE OF TESTING :-
- ➤ This test is done for determining of the maximum dry density in( g/cm3) at optimum moisture content of the soil.
IS REFERANCE :-
- IS: 2720 Part 2 Method for sampling soil.
- IS: 2720 Part -VII Determination of moisture content & dry density relation by using light compaction method.
TEST EQUIPMENTS :-
- Cylinder metal mould having dia 10cm, internal height 117cm & capacity 0.945lit.
- Detachable base plate.
- Collar 50mm height.
- Rammer, having wt 2.6kg & 310mm ht.
- Air Tight container.
- Straihtedge.
TEST PROCEDURE :-
- Take about 3kg of air-dried & pulverized soil, passing 4.75 mm IS Sieve.
- Mix it thoroughly over a big tray.
- Then the mixer keep cover with a wet cloth & left it for 30min to proper absorption of water.
- First add water 2% of the wt of the soil with the soil sample.
- Then mix it properly again for few minute.
- Pour the soil sample into the mould in layer at a 1/3 height of mould & compacted by uniformly distributed 25 blows of the rammer over the surface.
- Before putting second installment scratch the top surface of the first compacted layer.
- Second & third layer are similarly compacted & last layer should not project more than 6mm.
- Take wt of the mould, base plate & the compacted soil.
- Then de -mould the soil & collect representative sample from the center.
- Check the moisture content (Wm) either by moisture meter or by thermostatically hot air oven.
- Then increase the % of water adding with the sample & continue the process at least 6 to 7 times.
- The water content corresponding to maximum dry density is called optimum moisture content.
- Plot a curve between water content as abscissa & dry density as ordinate. Mark the max dry density & corresponding water content in the graph.
CALCULATIONS :-
- Water added in cc.
- Weight of compacted soil + mould (W1), in gm.
- Weight of empty mould (W2), in gm.
- Volume of mould (V), in cc.
- Weight of compacted soil (W1 - W2), in gm.
- Wet density (Ba) in gm/ cc.
- Water content container No.
- Weight of soil for water content determination (Wa), in gm.
- Weight of oven dried soil (Wb), in gm.
PRACTICAL MODULE:-
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