4.3 Cone penetration and piezocone penetration tests (CPT, CPTU)
(1) The objective of the cone penetration test (CPT) is to determine the resistance of soil and soft rock to the penetration of a cone and the local friction on a sleeve.
(2) P The CPT consists of pushing a cone penetrometer vertically into the soil using a series of push rods. The cone penetrometer shall be pushed into the soil at a constant rate of penetration. The cone penetrometer comprises the cone and if appropriate a cylindrical shaft or friction sleeve. The penetration resistance of the cone qc as well as, if appropriate, the local friction on the friction sleeve shall be measured.
Porewater pressure measurement:
u1: on the cone face
u2: at the cylindrical extension of the cone
u3: directly behind the friction sleeve