| Abstract: | Partial drainage often occurs during piezocone penetration testing on Yellow River Delta silt because of its intermediate physical and mechanical properties between those of sand and clay. Yet, there is no accurate understanding for the range of penetra-tion rates to trigger the partial drainage of silt soils. In order to fully investigate cone penetration rate effects under partial drainage condi-tions, indoor 1 g penetration model tests and numerical simulations of cavity expansion at variable penetration rates were carried out on the Yellow River Delta silt. The boundary effect of the model tests and the variation of key parameters at the different cavity ex-pansion rates were analyzed. The 1 g penetration model test results and numerical simulations results consistently indicated that the penetration rate to trigger the partially drainage of typical silt varied at least three orders of magnitude. The numerical simulations also provide the reference values for the penetration resistance corresponding to zero dilation and zero viscosity at any given normalized penetration rate for silt in Yellow River Delta. These geotechnical properties can be used for the design of offshore platforms in Yel-low River Delta, and the understanding of cone penetration rate effects under the partially drained conditions would provide some technical support for geohazard evaluation of offshore platforms. |
