Cbr Machine California Bearing Ratio

A California Bearing Ratio (CBR) machine is a laboratory testing equipment used to determine the bearing capacity and strength of subgrade soils and base materials for road and pavement design. It measures the resistance of a compacted soil sample to penetration under controlled loading. Key Features • Motorized loading frame with constant penetration rate (1.25 mm/min) • Proving ring or load cell for accurate load measurement • Dial gauges / digital display for penetration reading • CBR mould (150 mm diameter) with spacer disc and collar • Soaking tank for soaked CBR testing • Robust steel frame for stability Use • Determination of CBR value (%) • Pavement thickness design • Subgrade strength evaluation Commonly performed according to: • ASTM International – ASTM D1883 • British Standards Institution – BS 1377