Inclined single piles under vertical loadings in cohesionless soil

• Published in: Acta geotechnica 2021-04, Vol.16 (4), p.1231-1245
• Main Authors: Goit, Chandra Shekhar, Saitoh, Masato, Igarashi, Takumi, Sasaki, Shun
• Format: Article
• Language: English
• Subjects: Amplitude; Amplitudes; Bending; Cohesionless soils; Complex Fluids and Microfluidics; Deformation; Earthquakes; Engineering; Foundations; Geoengineering; Geotechnical Engineering & Applied Earth Sciences; Hydraulics; Model testing; Nonlinear systems; Nonlinearity; Piles; Research Paper; Soft and Granular Matter; Soil; Soil dynamics; Soil Science & Conservation; Soil testing; Soils; Solid Mechanics; Strain gauges; Vertical loads
• ISSN: 1861-1125; 1861-1133
• DOI: 10.1007/s11440-020-01074-9

Physical-scaled model testing under 1  g conditions is carried out in obtaining the vertical response of fixed head floating-inclined single piles embedded in dry sand. Practical pile inclinations of 5° and 10° besides a vertical pile (0°) subjected to static and dynamic vertical pile head loadings are considered. To account for the effects of soil nonlinearity as well as the soil–pile interface nonlinearity on the response of piles, a range of low-to-high magnitude of pile head displacements is considered for the static case while a varying amplitude of harmonic accelerations for a wide range of frequencies is considered for the dynamic case. Experimental results are obtained in the form of pile head stiffnesses and strains generated in the pile under both the static and dynamic loadings. Results suggest that the nonlinear behavior of soil as well as the nonlinearity generated at the interface between the soil and the pile as the result of applied loading considerably affect the response of piles. The soil–pile interface nonlinearity that governs the slippage of pile shows a clear influence on the pile head stiffnesses by providing two distinct values of stiffnesses corresponding to the push and the pull directional movement of piles; the two values are significantly different. Axial and bending strains generated in the piles show expected dependency on the amplitude of applied loading; the pile head-level bending strain increases almost linearly with the increase in the angle of pile inclination.