Low cbr values (<10%) mean the subgrade is weak, requiring thicker pavement or soil stabilization. Cbr is the ratio of force required to penetrate a soil mass with a standard circular piston to a specific depth at the rate of 1.25 mm/min., to that required for the corresponding. The result is then compared to the standard material's penetration force.
A load penetration curve is drawn. The california bearing ratio (cbr) is described as the ratio of the force per unit area needed to penetrate a soil mass using a standard circular plunger with a diameter of 50. High cbr values (>30%) indicate strong soil, reducing the need for.
The cbr test measures the force required to push a plunger into the soil sample at a specific rate. The california bearing ratio is not only. This means that more than half of the individual grains are visible to the naked eye. This is expressed as a percentage of the.
A cbr value of 5% is often considered the minimum acceptable value for road construction in many regions, indicating poor subgrade strength. The cbr is expressed as a percentage of the actual load causing the penetrations of 2.5 mm or 5.0 mm to the standard loads on crushed stone.