Three dimensional finite element modeling for the laterally loaded passive pile behavior

Ekici, Anıl
In this study, some of the factors affecting the slope stabilizing pile response have been investigated by means of three dimensional finite element solution using PLAXIS 3D software. Three full scaled field experiments were modeled for the verification of the proposed 3D models. It was concluded that PLAXIS 3D can successfully predict the measured pile deflection and force distributions. Afterwards, a parametric study was carried out. Two series of analyses (i) studying the effect of the pile embedment depth and (ii) studying the effect of pile spacing were performed. Some of the conclusions of this study are: (1) There is a critical pile embedment depth necessary to provide sufficient pile resistance, and this depth depends on unstable soil properties and strength ratio of stable soil to unstable soil. (2) As piles get closer (smaller s/d), load on each pile decreases and soil arching increases (i.e. less flowing of the soil between the piles). So there is an optimum pile spacing by considering soil arching and group reduction phenomena. (3) For sandy soils, effect of soil arching significantly decreases for pile spacing ratios (s/d) larger than 6. Piles in group start to behave like individual piles approximately at s/d=8. Stronger soil arching develops at pile spacing ratios (s/d) between 2 and 4. (4) Significant group reduction develops when piles are closely spaced. Approximately 30% reduction was observed in lateral loads exerted to piles in group for s/d=2. Therefore, s/d=4 was seen to be more optimum value for an effective pile design.


Integrated limit equilibrium method for slope stability analysis
Yalçın, Yağızer; Pekcan, Onur; Department of Civil Engineering (2018)
Limit equilibrium is a well-established concept with successful implementations to slope stability analysis problems. Based on different underlying assumptions, there are numerous limit equilibrium methods (LEMs), yet all of them interpret the system reliability to that of the critical slip surface, which requires iterative optimization procedures to locate. Therefore, a complete analysis framework involves modules to (i) generate/represent, (ii) analyze and (iii) optimize slip surfaces, all of which influe...
Ünlü, Kahraman; BIGGAR, JW; MORKOC, F (Wiley, 1990-11-01)
The knowledge of the statistical parameters of the variance, sigma-2, and the correlation scale, lambda, characterizing the spatial structures of the log of the saturated hydraulic conductivity, lnK(s), pore size distribution parameter alpha, and the specific water capacity, C, is required in stochastic modeling in order to understand the overall response of large-scale heterogenous unsaturated flow systems. These parameters are estimated assuming second-order stationarity and an exponential semivariogram ...
Three dimensional computational analysis of fatigue crack propagation in functionally graded materials
Sabuncuoglu, Baris; Dağ, Serkan; YILDIRIM, BORA (Elsevier BV, 2012-02-01)
This article proposes a new finite elements based three dimensional method developed to study the phenomenon of fatigue crack propagation in functionally graded materials (FGMs). The particular problem examined in detail is that of an initially-elliptical crack located in a functionally graded medium, subjected to mode I cyclic loading. The crack is modelled by employing three dimensional finite elements; and the stress intensity factors (SIFs) around the crack front are computed by the application of the d...
Three dimensional frame element formulation for nonlinear analysis of semi rigid steel structures
Özel, Halil Fırat; Sarıtaş, Afşin; Karakaş, Zafer (null; 2016-09-21)
In this paper, a force-based three-dimensional frame finite element formulation with spread of inelasticity through the element and localized nonlinear semi-rigid connections is developed. The proposed model utilizes Euler-Bernoulli beam theory assumptions, and adopts fiber discretization of monitored sections along element length and section depth for the spread of inelasticity in order to capture axial force and biaxial bending moment interaction. Defining any type of semi-rigid either linear or nonlinear...
A stabilized finite element method for the two-field and three-field Stokes eigenvalue problems
Türk, Önder; Codina, Ramon (2016-10-01)
In this paper, the stabilized finite element approximation of the Stokes eigenvalue problems is considered for both the two field (displacement pressure) and the three-field (stress displacement pressure) formulations. The method presented is based on a subgrid scale concept, and depends on the approximation of the unresolvable scales of the continuous solution. In general, subgrid scale techniques consist in the addition of a residual based term to the basic Galerkin formulation. The application of a stand...
Citation Formats
A. Ekici, “Three dimensional finite element modeling for the laterally loaded passive pile behavior,” M.S. - Master of Science, Middle East Technical University, 2013.