EXPERIMENT NO AIM :- To perform water absorption test ... - Raisoni

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EXPERIMENT NO AIM:- To Determine California Bearing ratio [CBR] value and sub grade thickness for compacted soil under given traffic load. APPARTAUS:- FIGURE :- CBR apparatus consisting of mould of 150mm dia with a base plate and a collar, a 50mm dia, gauge for measuring expansion soaking and penetration
THEORY :- Hence WORKING :- PROCEDURE :- This method was originally devised by O. J. Parter, then the California State Highway, by other authority in USA, notably the US Corporation Of Engineering. The method combines a load penetration test perform in a lab. This is probably the most widely used method for the design of flexible pavement. The thickness of various elements comprising a p avement is determine by CBR values. It is a small scale p enetration test in which a cylindrical plunger 5 mm dia. is pen etrated into a soil mass. The observation are taken between the penetr ation resistance into a soil mass at the ratio of 0.05 inch / min [1.25 mm / min ]. The observations are tak en between the penetration resistance verses the penetration of plunger. The California Bearin g Ratio is defined as the ratio of test load to the standard load expressed in percentage CBR = [Test Load / Standard load ] x 100 The CBR test is carried on a compacted soil in a CBR 150 mm dia. and 175 mm height provided with a detachable collar of 50 mm deep to be kept in the mould during the sp ecimen penetration which enables a specimen of 1 25 mm deep to be obtained . The moulding dry density and water content should be same as it should be maintained during field compaction. To estimate th e worst moisture condition of the field, the specimen is submerged in water for about 4 days before testing. Generally CBR value for both soaked and unsoaked sample and determined both during soaking and penetration the specimen is carried with equal surcharge weights to estimate the effect of overlying parameters or particular layer under construction . Each surcharge weight 147 mm dia with a general hoe of 153 mm in did and weighing 2.5 kg is considered approximately equivalent to 6.5 cm of construction . A minimum of two weights are placed as sp ecimen load is applied on the penetration piston to obtained the penetration of 1.25 mm / min . The max imum load and penetration is recorded if it occurs for penetration less than 7 mm. The soil sample approximately 2000 gm is weighted and transformed in a tray . About 7 % of water of total weight of soil sample is added in the soil and mix it properly This moisturized sample is compacted in the CBR in different layers . Each layer is compacted by giving 56 no of blows by tamp ering rod . After compaction the mould is placed under CBR testing machine and adjusted properly . The load is applied gradually by this pressure testing machine and various sets of r eadin g are taken until soil specimen fails.
Page 1 and 2: EXPERIMENT NO AIM :- To perform wat
Page 3 and 4: AIM :- EXPERIMENT NO To determine f
Page 5 and 6: (W2-W1 ) FIGURE :- (W2-W1 ) EXPERIM
Page 7 and 8: EXPERIMENT NO AIM: - To determine t
Page 9: THEORY: - PROCEDURE: - OBSERVATION:
Page 13 and 14: The sub grade thickness is given by
Page 15 and 16: RESULT :- PRECAUTION :- The average
Page 17 and 18: THEORY :- PROCEDURE :- OBSERVATION
Page 19 and 20: OBSERVATION TABLE :- out . It is al
Page 21: OBSERVATION TABLE :- Ball No. Tempe

EXPERIMENT NO AIM :- To perform water absorption test ... - Raisoni

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