Computational 3D finite element analyses of model passive piles

Kahyaoğlu, Mehmet Rifat; İmançlı, Gökhan; Öztürk, Alptuğ; Kayalar, Arif Ş.

doi:10.1016/j.commatsci.2009.02.022

Cited by 26 publications

(14 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Non-associated Mohr-Coulomb (MC) model is commonly used for dense sand and stiff clay in geotechnical engineering. This simple model is able to produce reasonably close results to both experimental data and field data for geotechnical problems like piles [1][2][3], deep excavation [4][5][6][7][8], and tunneling [9,10]. For the MC model, the non-associated flow rule implies that the dilation angle, which controls the volumetric strain of the soil, is different from the friction angle of the soil.…”

Section: Introductionmentioning

confidence: 93%

Preconditioned IDR(s) iterative solver for non‐symmetric linear system associated with FEM analysis of shallow foundation

Tran

Toh

Phoon

2013

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

SUMMARYNon-associated flow rule is essential when the popular Mohr-Coulomb model is used to model nonlinear behavior of soil. The global tangent stiffness matrix in nonlinear finite element analysis becomes nonsymmetric when this non-associated flow rule is applied. Efficient solution of this large-scale nonsymmetric linear system is of practical importance. The standard Krylov solver for a non-symmetric solver is Bi-CGSTAB. The Induced Dimension Reduction [IDR(s)] solver was proposed in the scientific computing literature relatively recently. Numerical studies of a drained strip footing problem on homogenous soil layer show that IDR(s = 6) is more efficient than Bi-CGSTAB when the preconditioner is the incomplete factorization with zero fill-in of global stiffness matrix K ep (ILU(0)-K ep ). Iteration time is reduced by 40% by using IDR(s = 6) with ILU(0)-K ep . To further reduce computational cost, the global stiffness matrix K ep is divided into two parts. The first part is the linear elastic stiffness matrix K e , which is formed only once at the beginning of solution step. The second part is a low-rank matrix Δ, which is re-formed at each Newton-Raphson iteration. Numerical studies show that IDR(s = 6) with this ILU(0)-K e preconditioner is more time effective than IDR(s = 6) with ILU(0)-K ep when the percentage of yielded Gauss points in the mesh is less than 15%. The total computation time is reduced by 60% when all the recommended optimizing methods are used.

show abstract

Section: Introductionmentioning

confidence: 93%

Preconditioned IDR(s) iterative solver for non‐symmetric linear system associated with FEM analysis of shallow foundation

Tran

Toh

Phoon

2013

Num Anal Meth Geomechanics

View full text Add to dashboard Cite

show abstract

“…In addition, other researchers used computational methods for soils performance (i.e., [19][20][21]). Finalluy, Kahyaoglu et al [22] used PLAXIS 3D Foundation to investigate the behavior of laterally loaded pile and pile group.…”

Section: Introductionmentioning

confidence: 99%

Influence of axial load on the lateral pile groups response in cohesionless and cohesive soil

Abbasa

Chik

Taha

2015

Front. Struct. Civ. Eng.

View full text Add to dashboard Cite

The lateral response of single and group of piles under simultaneous vertical and lateral loads has been analyzed using a 3D finite element approach. The response in this assessment considered lateral pile displacement and lateral soil resistance and corresponding p-y curve. As a result, modified p-y curves for lateral single pile response were improved with respect to the influence of increasing axial load intensities. The improved plots can be used for lateral loaded pile design and to produce the group action design p-multiplier curves and equations. The effect of load combination on the lateral pile group response was performed on three pile group configurations (i.e., 2Â1, 2Â2 and 3Â2) with four pile spacings (i.e., s = 2D, 4D, 6D and 8D). As a result, design curves were developed and applied on the actual case studies and similar expected cases for assessment of pile group behavior using improved p-multiplier. A design equation was derived from predicted design curves to be used in the evaluation of the lateral pile group action taking into account the effect of axial load intensities. It was found that the group interaction effect led to reduced lateral resistance for the pile in the group relative to that for the single pile in case of pure lateral load. While, in case of simultaneous combined loads, large axial load intensities (i.e., more than 6H, where H is lateral load values) will have an increase in p-multiplier by approximately 100% and will consequently contribute to greater group piles capacities.

show abstract

“…These methods are classified under five categories, as: (a) empirical stiffness distribution method [8], (b) hybrid model [9] (c) characteristic load method [21] (d) continuum methods [12], and (e) finite element method [15].…”

Section: Introductionmentioning

confidence: 99%