The CBR Test is used for determining the relative bearing ratio and expansion characteristics under known surcharge weights of base, sub-base and sub grade soils for the design of Roads, pavements, & Runways.
Tests can be conducted on all types of soils including sand ,gravel & washed stone (passing through 20 mm IS Sieve).
The CBR test is used extensively in selection of materials and control of subgrades.
The procedure consists of loading soil with a circular piston, 50 mm dia face and maintaining a penetration rate of 1.25 mm/min strain.
The load is noted and the results of test on natural or recompacted soils, in soaked and un soaked conditions , can be compared with standard test results. CBR App. Consists of the following:-
C.B.R. Apparatus, motorized-cum-hand 50 KN cap. with 1.25 mm/min rate of strain. Operation on 230 V, single phase, A.C. 50 Hz., A.C.
Accessories:
C.B.R. Mould, 150 mm dia x 175 mm high with extension collar and perforated base plate.
Penetration Piston, face dia 50 mm with adjustable bracket.
Displacer block (Spacer Disc) 148mm dia x 47.7mm high with detachable handle.
Perforated Swell plate, 148mm dia with adjustable stem and lock nut-Gunmetal/Brass.
Annular metal weight, 2.5kg. 147 mm dia with 53 dia central hole
Slotted metal weight, 2.5 kg. 147 mm dia with 53 mm dia slot.
Metal tripod stand for dial gauge.
Cutting collar.
Rammer, 2. 6kg weight with a drop of 310 mm. j. Rammer, 4.89kg weight with a drop of450 mm k. High sensitivity Proving Ring, 20 KN cap. fitted with 0.002 mm dial gauge with calibration certificate in nice teak wooden case. 1. Dial gauge 0.01 mm x 25 mm travel.
Accessories:
m. Annular metal wt. 5kg., 147mm dia. with 53
dia central hole, n. Slotted metal wt. 5kg., 147 mm dia. with 53 mm