How Test Soil In Laboratory.

Soils .

1: Q_  How will you prepare sample for proctor if there are soft particles in the sample ?

    A. By preparing 5 individual samples having different moisture content discard sample every each test.

2:Q_   What is the minimum surcharge weight place in doing a C.B.R. test ?

  A.   10 lbs. ( 4.54 kg. )

3:Q_   How do you calculate actual surcharge weight for C.B.R. ?

  A.  By equation  : W = D x V x A

            Where A = Area of mold

                       W = Actual surcharge weight

                        D = Density of materials

                        V = Thickness of layers 

4: Q_ What is the difference between a standard proctor test a modified proctor test ?

   A. Aside from the compactive energy which is 5 times greater than in the standard test , the maximum density and optimum water content obtained from the two compaction test is greater in fine-grained that for a coarse-grained soils.

5:Q_  What is S.P.T. ? Describe the procedure of this test in detail. 

   A.  S.P.T or standard penetration test :

The standard split-tube sampler 18 inches in length and 2 inches in diameter is driven into the soils , with a drive weight of 63.5 kg. at 30 inches free falling. The blow count for the first 6 inches is not used as this is to seat the sampler below the disturbed soil in the bottom of borehole. The number of blows to drive the final 12 inches is the penetration resistance. If it is not practical to drive the sampler the full 12 inches because of very dense , cemented hardpan, rock etc. The boring log will indicate the blow count and penetration as ratio i. e. 70: 4 for 70 blows and 4 inches in penetration .....