I.A. Miklashevich¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.4, pp. 145-152, 2010, DOI:10.3970/icces.2010.015.145

Abstract The simple analytical model for the energy flux by the earthquake is proposed. The energy flux can be evaluated through the Umov-Pointing vector by the rupture propagation in media. Discontinuity of vector components is found. This discontinuity cause the change of an energy flow direction and localization of the energy field. More >

A. Grebennikov¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.15, No.3, pp. 85-90, 2010, DOI:10.3970/icces.2010.015.085

Abstract New General Ray (GR) method for solution of the Dirichlet boundary value problem for the class of elliptic Partial Differential Equations (PDE) is proposed. GR-method consists in application of the Radon transform directly to the PDE and in reduction PDE to assemblage of Ordinary Differential Equations (ODE). The class of the PDE includes the Laplace, Poisson and Helmgoltz equations. GR-method presents the solution of the Dirichlet boundary value problem for this type of equations by explicit analytical formulas that use the direct and inverse Radon transform. Proposed version of GR-method justified theoretically, realized by fast algorithms and MATLAB software, which… More >

Ming-Hsiao Lee^1,2, Wen-Hwa Chen^1,3

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.4, pp. 115-124, 2010, DOI:10.3970/icces.2010.014.115

Abstract The meshless method has a distinct advantage that it needs only nodes without an element mesh which usually induces time-consuming work and inaccuracy when the elements are distorted during the analysis process. However, the element mesh provides the geometric information for numerical simulation without the need to judge if the nodes or integration points are inside the analysis domain as in the meshless method, such as the boundary of the analysis domain which is defined by the element's edges or faces and that the integration points are intrinsically inside the elements. Because the analysis model with only nodes in the… More >

Arif Amirov¹, Mustafa Yildiz¹, Zekeriya Ustaoglu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 115-124, 2009, DOI:10.3970/icces.2009.012.115

Abstract In this work we deal with solvability and aproximation to the solution of the two dimensional integral geometry problem for a family of regular curves of given curvature. Solvability of the problem is proved by using the Galerkin method and an algorithm is developed to compute the approximate solution of the problem. More >

S.V. Plotnikova¹, M.G. Kulikov¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.11, No.2, pp. 49-52, 2009, DOI:10.3970/icces.2009.011.049

Abstract This article has no abstract. More >

A.P.S. Selvadurai¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.8, No.3, pp. 121-126, 2008, DOI:10.3970/icces.2008.008.121

Abstract This paper examines the mechanics of brittle fragmentation that can occur in geomaterials subjected to critical stress states that promote fragmentation as opposed to plastic flow. The discrete element technique is used to examine the dynamic interaction between a moving ice floe and a stationary structure. The results illustrate the influence of fragmentation on the reduction of the dynamic interactive stresses. More >

C. Janna¹, M. Ferronato¹, G. Gambolati¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.4, pp. 239-244, 2008, DOI:10.3970/icces.2008.006.239

Abstract The geomechanical simulation of a faulted producing reservoir is a strongly non-linear problem due to the non-elastic behaviour of the depleted rocks and especially to the contact constraint prescribed on the fault surfaces. With penalty interface elements for the fault modeling the stiffness matrix may be severely ill-conditioned and the solution by the Preconditioned Conjugate Gradient requires the development and the implementation of ad hoc preconditioners. The present communication investigates the performance of a multilevel incomplete factorization aimed at enhancing convergence and reducing the computational cost of a non-linear geomechanical simulation. More >

G.M. Kulikov¹, E. Carrera², S.V. Plotnikova¹, S. Brischetto²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.3, pp. 187-192, 2008, DOI:10.3970/icces.2008.005.187

Abstract This paper presents the geometrically exact assumed stress-strain four-node element with nine displacement degrees of freedom per node. The finite element formulation developed is based on the 9-parameter shell model by employing a new concept of interpolation surfaces (I-surfaces) inside the shell body. We introduce three I-surfaces and choose nine displacements of these surfaces as fundamental shell unknowns. Such choice allows us to represent the higher-order shell formulation in a very compact form and to derive in curvilinear reference surface coordinates the strain-displacement relationships, which are objective, i.e. invariant under all rigid-body motions. More >

T. Tanaka¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.4, pp. 251-256, 2007, DOI:10.3970/icces.2007.004.251

Abstract The viscoplastic constitutive relations with kinematic strain hardening-softening model for geomaterials are developed. The constitutive models include strain-rate dependent properties based on the thoery by Duvaut-Lions. The dynamic relaxation method for static problems and the dynamic analysis for earthquake responses are applied to boundary value problems using finite element methods. More >

N. Ohno¹, D. Okumura¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.4, pp. 207-214, 2007, DOI:10.3970/icces.2007.004.207

Abstract The self energy of geometrically necessary dislocations (GNDs) is considered to inevitably introduce the higher-order stress work-conjugate to slip gradient in single crystals. It is pointed out that this higher-order stress stepwise changes in response to in-plane slip gradient and thus directly influences the onset of initial yielding in polycrystals. The self energy of GNDs is then incorporated into the strain gradient theory of Gurtin (2002). The resulting theory is applied to model crystal grains of size D, leading to a D-1-dependent term with a coefficient determined by grain shape and orientation. It is thus shown that the self energy… More >