New concept of drilling auger for displacement pile installation

Adam Krasiński

doi:10.1201/9781003431749-459

New concept of drilling auger for displacement pile installation

Abstract

In 2020, a new version of the screw displacement auger for pile installation in soil was developed and patented in Poland. It was named DPDT (Displacement Pile Drilling Tool). The general aim of its development was to reduce the soil resistances to the auger during screwing into the ground while maintaning a good load-bearing capacity for the screw displacement piles. The “DPDT-Auger” prototype was tested as a scaled-down model in the laboratory as well as in full-scale in the field. Its efficiency was compared with an ordinary SDP auger in two ways: by assessing soil resistances during screwing into the ground and by assessing the bearing capacity of completed piles. This paper presents the field tests and their results. Over 80 piles were tested in six test sites. Among them, 24 piles were instrumented and subjected to static load tests. The test results were generally positive and showed that the DPDT auger generates less torque than the SDP auger but requires more rotations and a slightly longer pile installation time. When it comes to the bearing capacity of the compression load, both DPDT and SDP piles showed similar characteristics.