Probabilistic simulation of entire process of rainfall-induced landslides using random finite element and material point methods with hydro-mechanical coupling

Purpose – Liquefaction of soils is defined as significant reduction in shear strength and stiffness due to increase in pore water pressure. This phenomenon can occur in static (monotonic) or dynamic loading patterns. However, in each pattern, the inherent variability of the soil parameters indicates that this problem is of a probabilistic nature rather than being deterministic. The purpose of this paper is to present a method, based on random finite element method, for reliability assessment of static liquefaction of saturated loose sand under monotonic loading. Design/methodology/approach – The random finite element analysis is used for reliability assessment of static liquefaction of saturated loose sand under monotonic loading. The soil behavior is modeled by an elasto-plastic effective stress constitutive model. Independent soil parameters including saturated unit weight, peak friction angle and initial plastic shear modulus are selected as stochastic parameters which are modeled using a truncated normal probability density function (pdf). Findings – The probability of liquefaction is assessed by pdf of modified pore pressure ratio at each depth. For this purpose pore pressure ratio is modified for monotonic loading of soil. It is shown that the saturated unit weight is the most effective parameter, within the selected stochastic parameters, influencing the static soil liquefaction. Originality/value – This research focuses on the reliability analysis of static liquefaction potential of sandy soils. Three independent soil parameters including saturated unit weight, peak friction angle and initial plastic shear modulus are considered as stochastic input parameters. A computer model, coded in MATLAB, is developed for the random finite element analysis. For modeling of the soil behavior, a specific elasto-plastic effective stress constitutive model (UBCSAND) was used.

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Finite element modeling of residual stress profile patterns in hard turning

Powder Diffraction ◽

10.1154/1.3133135 ◽

2009 ◽

Vol 24 (S1) ◽

pp. S22-S25

Author(s):

Y. B. Guo ◽

S. Anurag

Keyword(s):

Residual Stress ◽

Finite Element ◽

Finite Element Modeling ◽

Hard Turning ◽

Internal State ◽

Stress Profile ◽

Surface Residual Stress ◽

Mechanical Coupling ◽

Element Modeling ◽

Stress Profiles

Hard turning, i.e., turning hardened steels, may produce the unique “hook” shaped residual stress (RS) profile characterized by surface compressive RS and subsurface maximum compressive RS. However, the formation mechanism of the unique RS profile is not yet known. In this study, a novel hybrid finite element modeling approach based on thermal-mechanical coupling and internal state variable plasticity model has been developed to predict the unique RS profile patterns by hard turning AISI 52100 steel (62 HRc). The most important controlling factor for the unique characteristics of residual stress profiles has been identified. The transition of maximum residual stress at the surface to the subsurface has been recovered by controlling the plowed depth. The predicted characteristics of residual stress profiles favorably agree with the measured ones. In addition, friction coefficient only affects the magnitude of surface residual stress but not the basic shape of residual stress profiles.

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Random finite element analysis of backward erosion piping

Computers and Geotechnics ◽

10.1016/j.compgeo.2021.104322 ◽

2021 ◽

Vol 138 ◽

pp. 104322

Author(s):

B.A. Robbins ◽

D.V. Griffiths ◽

Gordon A. Fenton

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Element Analysis ◽

Backward Erosion Piping ◽

Random Finite Element

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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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Random finite element method for bearing capacity assessment of a shallow foundation under varied uniaxial loadings

International Journal of Reliability and Safety ◽

10.1504/ijrs.2018.094939 ◽

2018 ◽

Vol 12 (3) ◽

pp. 237

Author(s):

Amal Hentati ◽

Mbarka Selmi ◽

Tarek Kormi ◽

Nizar Bel Hadj Ali

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Bearing Capacity ◽

Shallow Foundation ◽

Capacity Assessment ◽

Random Finite Element Method ◽

Random Finite Element ◽

Element Method

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Microstructure-Based Random Finite Element Method Simulation of Frost Heave: Theory and Implementation

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198118798721 ◽

2018 ◽

Vol 2672 (52) ◽

pp. 347-357 ◽

Cited By ~ 1

Author(s):

Shaoyang Dong ◽

Xiong (Bill) Yu

Keyword(s):

Finite Element ◽

Ground Surface ◽

Finite Element Method Simulation ◽

Element Model ◽

Frozen Soil ◽

Traffic Load ◽

Frost Heave ◽

Holistic Model ◽

Water Pipes ◽

Random Finite Element

Frost heave can cause serious damage to civil infrastructure. For example, interactions of soil and water pipes under frozen conditions have been found to significantly accelerate pipe fracture. Frost heave may cause the retaining walls along highways to crack and even fail in cold climates. This paper describes a holistic model to simulate the temperature, stress, and deformation in frozen soil and implement a model to simulate frost heave and stress on water pipelines. The frozen soil behaviors are based on a microstructure-based random finite element model, which holistically describes the mechanical behaviors of soils subjected to freezing conditions. The new model is able to simulate bulk behaviors by considering the microstructure of soils. The soil is phase coded and therefore the simulation model only needs the corresponding parameters of individual phases. This significantly simplifies obtaining the necessary parameters for the model. The capability of the model in simulating the temperature distribution and volume change are first validated with laboratory scale experiments. Coupled thermal-mechanical processes are introduced to describe the soil responses subjected to sub-zero temperature on the ground surface. This subsequently changes the interaction modes between ground and water pipes and leads to increase of stresses on the water pipes. The effects of cracks along a water pipe further cause stress concentration, which jeopardizes the pipe’s performance and leads to failure. The combined effects of freezing ground and traffic load are further evaluated with the model.

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Rate-dependent electro-mechanical coupling response of ferroelectric materials: A finite element formulation

Mechanics of Materials ◽

10.1016/j.mechmat.2013.02.005 ◽

2013 ◽

Vol 62 ◽

pp. 44-59 ◽

Cited By ~ 13

Author(s):

Amir Sohrabi ◽

Anastasia Muliana

Keyword(s):

Finite Element ◽

Ferroelectric Materials ◽

Finite Element Formulation ◽

Element Formulation ◽

Mechanical Coupling ◽

Rate Dependent

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Cutting Force Predication Based on Integration of Symmetric Fuzzy Number and Finite Element Method

The Scientific World JOURNAL ◽

10.1155/2014/234150 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Zhanli Wang ◽

Yanjuan Hu ◽

Yao Wang ◽

Chao Dong ◽

Zaixiang Pang

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Cutting Force ◽

Fuzzy Number ◽

Experimental Result ◽

The Finite Element Method ◽

Mechanical Coupling ◽

Fuzzy Function ◽

Nonuniform Stress Field ◽

Element Method

In the process of turning, pointing at the uncertain phenomenon of cutting which is caused by the disturbance of random factors, for determining the uncertain scope of cutting force, the integrated symmetric fuzzy number and the finite element method (FEM) are used in the prediction of cutting force. The method used symmetric fuzzy number to establish fuzzy function between cutting force and three factors and obtained the uncertain interval of cutting force by linear programming. At the same time, the change curve of cutting force with time was directly simulated by using thermal-mechanical coupling FEM; also the nonuniform stress field and temperature distribution of workpiece, tool, and chip under the action of thermal-mechanical coupling were simulated. The experimental result shows that the method is effective for the uncertain prediction of cutting force.

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