Inclined single piles under vertical loadings in cohesionless soil
- PDF / 2,921,953 Bytes
- 15 Pages / 595.276 x 790.866 pts Page_size
- 76 Downloads / 226 Views
(0123456789().,-volV)(0123456789(). ,- volV)
RESEARCH PAPER
Inclined single piles under vertical loadings in cohesionless soil Chandra Shekhar Goit1
•
Masato Saitoh1 • Takumi Igarashi1 • Shun Sasaki1
Received: 28 July 2019 / Accepted: 12 September 2020 Ó Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Physical-scaled model testing under 1 g conditions is carried out in obtaining the vertical response of fixed head floatinginclined 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. Keywords Inclined single piles Internal forces Model testing Soil nonlinearity Vertical impedance functions Abbreviations Cu Coefficient of uniformity Cvv Imaginary part of vertical impedance functions d Diameter of pile Dmax;60;30;10 Particle size parameters for soil Maximum/minimum void ratio emax;min Young’s modulus of pile, soil Ep ; Es g Acceleration due to gravity Specific gravity of soil Gs H Depth of soil layer pffiffiffiffiffiffiffi i Imaginary unit (¼ 1) kvv Real part of vertical impedance functions S Static vertical stiffness of single pile kvv Kvv Vertical impedance functions L Length of pile Initial compressive load Pini u Applied pile head displacement & Chandra Shekhar Goit [email protected] 1
Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Saitama, Japan
Vs z cm ; cp g k ms qp ; qs xm ; xp
Shear wave velocity of soil Depth along the pile from the surface Dynamic strain in the model, prototype Density scaling ratio of model to prototype Geometric scaling ratio of model to prototype Poisson’s ratio of soil Density of pile, soil Circular frequency of model, prototype
1 Introduction Response of vertical piles subjected to lateral loads [
Data Loading...
