Dynamic penetration test with measuring of the pull-out resistance

Abstract

The cone penetration test is one of the most important and convenient tools for soil investigations. In recent decades, many efforts have been made to extend its applications to various fields in geotechnical engineering. This paper presents a newly developed dynamic cone penetration test with measuring of the pull-out resistance, which is named "Penetration & Pull-out Test (PPT)". PPT consists of the dynamic penetration test and the quasi-static pull-out resistance test. "N-value", the number of blows for penetration into soil under the undrained condition is measured from the dynamic penetration test, while the friction resistance of soil under the drained condition is measured from the quasi-static pull-out test. The validation test results indicate that PPT is highly useful for mitigation of liquefactioninduced problems due to earthquakes. PPT is a break-proof device because it is equipped without electrical sensor at the tip of the cone. As the future direction of this study, we will develop a more economical and simpler in-situ apparatus for judging the liquefaction susceptibility of soils.