PROBABILISTIC FINITE ELEMENT STIFFNESS OF A LATERALLY LOADED MONOPILE BASED ON AN IMPROVED ASYMPTOTIC SAMPLING METHOD

The mechanical responses of an offshore monopile foundation mounted in over-consolidated clay are calculated by employing a stochastic approach where a nonlinear p–y curve is incorporated with a finite element scheme. The random field theory is applied to represent a spatial variation for undrained shear strength of clay. Normal and Sobol sampling are employed to provide the asymptotic sampling method to generate the probability distribution of the foundation stiffnesses. Monte Carlo simulation is used as a benchmark. Asymptotic sampling accompanied with Sobol quasi random sampling demonstrates an efficient method for estimating the probability distribution of stiffnesses for the offshore monopile foundation.

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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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Finite element modeling of surge propagation and an application to the Hay River, N.W.T.

Canadian Journal of Civil Engineering ◽

10.1139/l92-055 ◽

1992 ◽

Vol 19 (3) ◽

pp. 454-462 ◽

Cited By ~ 11

Author(s):

F. E. Hicks ◽

P. M. Steffler ◽

R. Gerard

Keyword(s):

Finite Element ◽

Channel Flow ◽

Open Channel ◽

Initial Conditions ◽

Open Channel Flow ◽

Kinematic Wave ◽

Finite Element Scheme ◽

Flow Problems ◽

Ice Jam

This paper describes the application of the characteristic-dissipative-Galerkin method to steady and unsteady open channel flow problems. The robust performance of this new finite element scheme is demonstrated in modeling the propagation of ice jam release surges over a 500 km reach of the Hay River in Alberta and Northwest Territories. This demonstration includes the automatic determination of steady flow profiles through supercritical–subcritical transitions, establishing the initial conditions for the unsteady flow analyses. The ice jam releases create a dambreak type of problem which begins as a very dynamic situation then develops into an essentially kinematic wave problem as the disturbance propagated downstream. The characteristic-dissipative-Galerkin scheme provided stable solutions not only for the extremes of dynamic and kinematic wave conditions, but also through the transition between the two. Key words: open channel flow, finite element method, dam break, surge propagation.

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An adaptive finite element scheme to solve fluid-structure vibration problems on non-matching grids

Computing and Visualization in Science ◽

10.1007/s007910100057 ◽

2001 ◽

Vol 4 (2) ◽

pp. 67-78 ◽

Cited By ~ 6

Author(s):

Ana Alonso ◽

Anahí Dello Russo ◽

César Otero-Souto ◽

Claudio Padra ◽

Rodolfo Rodríguez

Keyword(s):

Finite Element ◽

Adaptive Finite Element ◽

Finite Element Scheme ◽

Fluid Structure ◽

Element Scheme ◽

Structure Vibration ◽

Vibration Problems

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Analysis of the Electro-Mechanical Responses of the Piezoelectric Motor Based on Finite Element Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.697.181 ◽

2014 ◽

Vol 697 ◽

pp. 181-186

Author(s):

Zi Lei Wang ◽

Tian De Qiu

Keyword(s):

Finite Element ◽

Coupling Effect ◽

Complex Stress ◽

Piezoelectric Resonator ◽

Element Analysis ◽

Mechanical Coupling ◽

Mechanical Responses ◽

Stress Boundary Condition ◽

Piezoelectric Field ◽

Stress Boundary

The piezoelectric field and structure field of piezoelectric resonator of ultrasonic motor are intercoupling. It is difficult to obtain the solution under some circumstances because of the complex stress boundary condition and the influence of coupling effect. An electro-mechanical coupling finite-element dynamic equation is established on the basis of the Hamilton’s Principle about piezoceramic and elastomer. The equation is decoupled through the shock excitation of the piezoelectric resonator and the piezoelectricity element and material provided by finite-element analysis. As a result, an admittance curve as well as the distribution status of the nodal DOF is obtained, which provides an effective method to solve electro-mechanical coupling problems.

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