Model Uncertainty for Displacement Prediction for Laterally Loaded Piles on Granular Fill

Manuel Bueno Aguado; Félix Escolano Sánchez; Eugenio Sanz Pérez

doi:10.3390/app10020613

Model Uncertainty for Displacement Prediction for Laterally Loaded Piles on Granular Fill

Applied Sciences ◽

10.3390/app10020613 ◽

2020 ◽

Vol 10 (2) ◽

pp. 613 ◽

Cited By ~ 1

Author(s):

Manuel Bueno Aguado ◽

Félix Escolano Sánchez ◽

Eugenio Sanz Pérez

Keyword(s):

Model Uncertainty ◽

Large Scale ◽

Site Investigation ◽

Laterally Loaded Piles ◽

Relevant Issue ◽

Displacement Prediction ◽

Laterally Loaded Pile ◽

Granular Fill ◽

Laterally Loaded ◽

Real Scale

Engineers are often concerned with the capability of a particular mathematical model to simulate a real-scale phenomenon. Model uncertainty is a relevant issue in order to assess the safety factor of a particular structure. In this paper, large-scale laterally loaded pile outputs are compared to predictions using well-known formulations. In this way, an insight on model uncertainty is presented. Both p-y method proposed by the API, and the horizontal reaction modulus proposed in many codes are used to predict displacement. Both are correlated to the site investigation. In this way, engineers are provided with a critical view of the available prediction methods to assess laterally loaded pile behaviour.

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Laterally Loaded Piles With Wings: In Situ Testing With Cyclic Loading From Varying Directions

Volume 6: Polar and Arctic Sciences and Technology; Offshore Geotechnics; Petroleum Technology Symposium ◽

10.1115/omae2013-10026 ◽

2013 ◽

Author(s):

Christina Rudolph ◽

Jürgen Grabe

Keyword(s):

Large Scale ◽

Load Level ◽

Lateral Loading ◽

Offshore Wind ◽

In Situ Tests ◽

Laterally Loaded Piles ◽

Offshore Wind Turbines ◽

Loading Direction ◽

Laterally Loaded

The application of piles as foundations for offshore wind turbines yields new requirements for the design. Wind and waves induce a cyclic lateral loading on the pile which changes direction corresponding to the meteorological conditions. Cyclic lateral loading on piles results in accumulated displacements, depending on the cyclic load level and load characteristics. The deformation can increase significantly due to a varying loading direction. Under such loading conditions the pile can drift sideways even if the loading is symmetric. Wings attached to the pile shortly below the seabed have been known to reduce deformations on laterally loaded piles as they locally enlarge the diameter on which the soil resistance is activated. They also change the cross-section of the pile from a circular shape to a star-shape. This might reduce the drifting of the pile. A series of large-scale in-situ tests has been carried out in order to identify the effects of changing loading direction as well as the applicability of winged piles to reduce deformations. Two tubular steel piles (one of them equipped with wings) have been installed and subjected to high-cyclic lateral loading from varying directions. In this paper the in-situ tests and their results are presented.

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Development of Simulation Based p-Multipliers for Laterally Loaded Pile Groups in Granular Soil Using 3D Nonlinear Finite Element Model

Applied Sciences ◽

10.3390/app11010026 ◽

2020 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Muhammad Bilal Adeel ◽

Muhammad Asad Jan ◽

Muhammad Aaqib ◽

Duhee Park

Keyword(s):

Finite Element ◽

Element Model ◽

Design Guidelines ◽

American Petroleum Institute ◽

Winkler Foundation ◽

Group Effect ◽

Pile Groups ◽

Element Analysis ◽

Laterally Loaded Pile ◽

Laterally Loaded

The behavior of laterally loaded pile groups is usually accessed by beam-on-nonlinear-Winkler-foundation (BNWF) approach employing various forms of empirically derived p-y curves and p-multipliers. Averaged p-multiplier for a particular pile group is termed as the group effect parameter. In practice, the p-y curve presented by the American Petroleum Institute (API) is most often utilized for piles in granular soils, although its shortcomings are recognized. In this study, we performed 3D finite element analysis to develop p-multipliers and group effect parameters for 3 × 3 to 5 × 5 vertically squared pile groups. The effect of the ratio of spacing to pile diameter (S/D), number of group piles, varying friction angle (φ), and pile fixity conditions on p-multipliers and group effect parameters are evaluated and quantified. Based on the simulation outcomes, a new functional form to calculate p-multipliers is proposed for pile groups. Extensive comparisons with the experimental measurements reveal that the calculated p-multipliers and group effect parameters are within the recorded range. Comparisons with two design guidelines which do not account for the pile fixity condition demonstrate that they overestimate the p-multipliers for fixed-head condition.

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