North Dakota Cone Test
North Dakota Cone Test is a cone penetration test similar to the California Bearing Ratio (C.B.R.) test developed by the North Dakota State Highways Deptt. This test is simpler and more rapid than the C.B.R. but its use is restricted to fine-grained soils and is considered reliable only for clayey soils. The penetrometer consists essentially of a shaft with a sharp cone attached to one end. The cone is loaded during the test by placing weights on a disc fixed to the top of the shaft and its penetration measured. The test is made directly on the sub-grade.