Determination Permeability Coefficient from Piezocone

Abstract

The permeability coefficient of soil profile is one of the problems concerned by engineers, and the determination of permeability coefficient method mainly relies on the laboratory permeability test and field pumping test, but these tests are time-consuming and inefficient, and especially the permeability coefficient of soil under the condition of partial drainage was difficult to determine; in this paper, the modern digital CPTU technology was used. Dimensional permeabilityKTwas defined by using the dimensionless normalized cone tip resistanceQt, friction factorFr, and pore pressure ratioBq, these parameters enable plots ofBq-Qt,Fr-Qt,Bq-Frto be contouredKTand hence for permeability coefficient. The relationship has been applied to Nanjing 4th Yangtze river bridge, and compared with laboratory penetration test. The results indicate that the method can accurately determine the permeability coefficient of soil under partial drainage condition and provide the theoretical basis for engineering application.