North Dakota Method for Soil Bearing capacity

North Dakota Method for Soil Bearing capacity

North Dakota Method for Soil Bearing capacity        This method is similar to CBR method for determine the soil bearing capacity of the sub-grade by means of cone penetration. This method is developed by North Dakota State Highway Department.        The penetrometer consists of essentially of shaft with sharp edge cone (half angle 7o 45’) attached at one end. The movement of shaft into the soil measured with the help of a vernier. The shaft can be locked to the frame when necessary. A disc is fixed to the top of the shaft, over which weights can be fixed.        The load is applied to the shaft, during penetration into the soil, divided by the area of the cone at the surface level is termed as the cone bearing value qc qc = Q/ (0.058 p2) qc = bearing value (kg/cm2) Q = load on cone (kg) P – penetration of cone (cm0        The load is used in the test are 4.5, 9, 18 and 36 kg, inclusive of the weight of the shaft and cone.