Tensile response of screw piles with varying installation approaches in layered sand

TY - JOUR

T1 - Tensile response of screw piles with varying installation approaches in layered sand

AU - Kumar, Pelluru Venkata Pavan

AU - Wang, Wei

AU - Brown, Michael

AU - Patra, Shantanu

AU - Haldar, Sumanta

AU - Sharif, Yaseen

AU - Knappett, Jonathan

N1 - Publisher Copyright: © 2025 Emerald Publishing Limited: All rights reserved.

PY - 2025/7/2

Y1 - 2025/7/2

N2 - Single or multiple helix screw piles are being considered as fast and economical foundation systems for onshore renewable energy units. These foundations may encounter distinct soil layering and need to perform under a variety of load cases. For this application, the installation and monotonic tensile load response of multiple helix screw piles in uniform and layered sands were investigated by centrifuge modelling. Standard pitch-matched and pile self-weight approaches to installation were considered. The latter is advantageous as it requires no additional vertical force during installation (minimising plant requirements), alongside improved tensile capacity and reduced installation torque. Tensile capacity could also be increased by the inclusion of additional helices, but soil properties and layering arrangement must be considered or tensile capacity may be reduced. The performance of existing tensile capacity design methods was investigated and compared with the test results. A cylindrical shearing mechanism appears appropriate for capacity prediction in the majority of layering arrangements explored. Where individual plate-bearing mechanisms dominate, a modification to an existing approach reasonably predicted tensile capacity for shallow mechanisms, while further work is required to develop reliable prediction methods for deep mechanism behaviour in layered soils.

AB - Single or multiple helix screw piles are being considered as fast and economical foundation systems for onshore renewable energy units. These foundations may encounter distinct soil layering and need to perform under a variety of load cases. For this application, the installation and monotonic tensile load response of multiple helix screw piles in uniform and layered sands were investigated by centrifuge modelling. Standard pitch-matched and pile self-weight approaches to installation were considered. The latter is advantageous as it requires no additional vertical force during installation (minimising plant requirements), alongside improved tensile capacity and reduced installation torque. Tensile capacity could also be increased by the inclusion of additional helices, but soil properties and layering arrangement must be considered or tensile capacity may be reduced. The performance of existing tensile capacity design methods was investigated and compared with the test results. A cylindrical shearing mechanism appears appropriate for capacity prediction in the majority of layering arrangements explored. Where individual plate-bearing mechanisms dominate, a modification to an existing approach reasonably predicted tensile capacity for shallow mechanisms, while further work is required to develop reliable prediction methods for deep mechanism behaviour in layered soils.

KW - Helical anchors

KW - Screw piles

KW - Sands

KW - Centrifuge modelling

KW - Foundations

KW - Piles & Piling

KW - piles & piling

KW - foundations

KW - sands

KW - centrifuge modelling

KW - helical anchors

KW - helical piles

KW - screw piles

UR - https://www.scopus.com/pages/publications/105010127895

U2 - 10.1680/jgeen.24.00385

DO - 10.1680/jgeen.24.00385

M3 - Article

SN - 1353-2618

JO - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

JF - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering

M1 - 2400385

ER -