This paper mainly describes the CPTU (piezocone penetration test) experiment in the chamber filled with the saturated clay . And through analyzing the data of the experiment, the change and distribution of vertical additional stresses and radial additional stresses, the change of cone resistance, sleeve friction and excess pore water pressure generated by the probe penetrating, and the change of pore water pressure around the probe in the excess pore water pressure dissipation have been shown, then the vari...