ISO 22476-10:2017 pdf free
ISO 22476-10:2017 pdf free.Geotechnical investigation and testing一Field testing
When the penetrometer is used as a static penetrometer in soft soils, the rod shall be loaded in steps using the following standard loads: 0 N, 50 N, 150 N, 250 N, 500 N, 750 N and 1 000 N. The maximum standard load is 1 000 N.
The minimum possible load shall be used to obtain penetration. The load shall be adjusted in the standard steps to give a rate of penetration of 20 mm/s minimum and 50 mm/s maximum. When a load step passes, the higher load step shall be recorded.
If the penetration resistance exceeds a load of 1 000 N or the penetration rate at a load of 1 000 N is less than 20 mm/s, the rod shall be rotated. The load of 1 000 N is maintained and the number of half turns required to give 200 mm penetration shall be counted. If the point penetrates from a firm layer into a soft or loose layer underneath it, the rods may start to penetrate without turning. In such conditions,the load shall be reduced to stop the penetration. After the rods stop, the load is increased to determine the minimum load needed for penetration. Then, the test shall be continued.
The rod shall not be rotated when the penetration resistance is less than 1 000 N.
If the penetration comes to a stop, the rods shall be struck with a sledgehammer or loaded with percussion drilling to check that the stop is not temporary. If possible, the sounding shall be continued with another rotation phase.
The sounding is terminated either
a) at the specified depth, or
b) when a firm layer is reached and the number of half turns increases to a specified number. The existence of the firm layer shall be checked by striking the rod with a sledgehammer, overloading or driving it with a percussion drilling unit. The applied method shall be chosen according to the specification of the investigation of the project site and it shall be presented in the field report.ISO 22476-10 pdf download.
