CBR Test
California Bearing Ratio from load–penetration readings: CBR at 2.5 and 5.0 mm, load–penetration curve, swell and subgrade rating. ASTM D1883 and IS 2720-16.
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About this test
Enter the proving-ring readings at each penetration. The sheet draws the load–penetration curve, reads the loads at 2.5 mm and 5.0 mm, and gives the CBR with a subgrade rating and the swell for soaked tests.
How it's calculated
- CBR = test load ÷ standard load × 100
- Standard load: 13.34 kN at 2.54 mm and 19.93 kN at 5.08 mm (ASTM)
- The higher of the two values governs (repeat the test if the 5 mm value is higher)
Results are calculated from the values you enter using standard formulas. Download the PDF to keep a record. For certified testing, design or construction, talk to our engineers.
Kataria Engineering & Consultancy Services (2026). CBR Test [online calculator]. https://katariaengineering.com/tools/cbr-test-calculator.html
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