Calibrating the stresstime curve of a combined finite discrete element method to a split hopkinson pressure bar experiment. The advantage of this approach lies in the fact that deformability can be well represented by finite elements, whilst d iscontinuities such a s cracks c an b e explicitly described by discrete elements. Pdf combined finitediscrete element analysis of rock slope. The combined finitediscrete element method pdf free. Such problems include fragmentation using explosives e. The combined finitediscrete element method a natural extension of both discrete and finite element methods allows researchers to model problems involving the deformability of either one solid body, a large number of bodies, or a solid body which fragments e. The combined finite discrete element method is a relatively new computational tool aimed at problems involving static and or dynamic behaviour of systems involving a large number of solid deformable bodies. A comprehensive treatment of the combined finite element discrete element method is contained in the book the combined finite discrete element method by. Pdf the combined finitediscrete element method semantic. Limits of applicability of the finite element explicit joint. Tangential force model for the combined finitediscrete. Seismic analysis of dry stone masonry structures based on.
Stability analysis of dry stone lintels using combined. Fdem couples dem and fem by generating a finite element mesh separately for each particle discrete element located within the computational domain. In numerical modeling, the interaction of nonuniform blast loading on the concrete slab was modeled using the incorporation of the finite element method with a crack rotating approach. Discrete element methods have been a common point for researchers to publish advances in the method and its applications. A typical combined finite discrete element simulation comprises large number thousands or even millions of particles which are represented by a single discrete element.
Introduction to the combined finitediscrete element method. Structural applications of the combined finitediscrete element method. Within the framework of femdem, discrete element method dem principles are used to model. Therefore, earthquakeinduced ground motion should be taken into account when performing slope stability analysis in seismically active areas of the world. Nodal values u1 and u2 are unknowns which should be determined from the discrete global equation system. Combined finitediscrete element modelling of rock fracture. These are i simulation of the deformability of a block, i. Space decomposition based parallelization solutions for the. For each particle, a full continuum finite element formulation is used, and thus a range of material models may be applied for the calculation of particle deformation. The tool of the machine has effect on the aggregate and vice versa. These methods are designed to handle contact situations in which transitions from continua to discontinua appear.
This paper presents the performance of a combined finite discrete element method femdem for seismic analysis of dry stone masonry structures. Masonry is a heterogeneous structural material consisting of bricks joined by mortar layers. These simulations utilize an inhouse implementation of the combined finite discrete element method fdem known as the hybrid optimization software suite hoss. Stability analysis of dry stone lintels using combined finite. In the proposed modelling approach each stone block is modelled as a discrete element which is discretized by constant strain triangular finite elements. Computational modeling of masonry structures using the. Combined finitediscrete element modelling of dynamic rock. The combined finite discrete element method fdem can well model the transition from continuous to discontinuous behavior in rock mass. Thus, finite element based analysis of continua is combined with discrete element based transient dynamics, cd and contact interaction solutions.
Combined finite discrete element method is intended for the dynamic analysis of a large number of mutually interacting discrete elements, where. Simulation of fracture coalescence in granite via the. Pdf some aspects of combined finitediscrete element. The essence of this method is to merge the algorithmic advantages of dem with those of the fem. Pdf combined finitediscrete element analysis of rock. The discrete element method dem developed originally by cundall and strack 3 is that the domain of interest is treated as an assemblage of rigid. Pdf combined finitediscrete element method for simulation of. Because of its potential benefits, the combined finite discrete element method works in the following way. The element is the basic building unit, with a predetermined number of dof. Simulation of crack induced nonlinear elasticity using the. Fracture failure of reinforced concrete slabs subjected to.
Yhfdem ide, used for modelling rock blasting in this study was originally developed by the authors 40 and recently parallelized on the basis of generalpurpose graphicprocessingunit gpgpu by the authors. The numerical modelling of masonry structures especially in the nonlinear range represents an. Though dem is very closely related to molecular dynamics, the method is generally distinguished by its inclusion of rotational degreesoffreedom as well as stateful contact and often complicated geometries. The mixed mode iii fracture of concrete is investigated by using a fourpoint combined discrete and finite elements method. Numerical simulation of hydromechanical couplings by. In the analysis of discrete problems three aspects need to be recognized. Modeling simultaneous multiple fracturing using the. The hybrid finite discrete element method fdem has become a highly popular means of simulating the failure process in natural and engineered materials due to its ability to model the transition from continuum to discontinuum by means of fracture and fragmentation processes. The combined finite discrete element method a natural extension of both discrete and finite element methods allows researchers to model problems involving the deformability of either one solid body, a large number of bodies, or a solid body which fragments e. A framework for grand scale parallelization of the. Our present combined finite discrete element method involves not only a large number of irregular particles but also the inversion of matrices for the solution of deformation within each particle. Keywords combined finitediscrete element method hybrid optimization. New combined finitediscrete element numerical code. On the use of combined finitediscrete element method for.
Numerical simulation of hydromechanical couplings by combined. In a finite discrete element analysis the main issues which require consideration, for both dynamic and quasistatic. The key component of the proposed method, that is, transition from continuum to discontinuum through fracture and fragmentation, is introduced in detail, which makes the proposed method superior to. It features a symbolic math kernel, which manipulates the strong or weak form of the problem and automatically derives the discrete form. In this brief video i will present two books that are very beginner friendly if you get started with the finite element method. The combined finite discrete element method fdem merges the. The combined finite discrete element method is a relatively new computational tool aimed at problems involving static and or dynamic behaviour of systems. A 2d coupled hydrothermal model for the combined finite discrete element method. International journal of rock mechanics and mining sciences, 70. Viennafem is built on top of the following libraries. A combined finitediscrete element method is proposed for the prediction of reinforced concrete structure response under severe dynamic loads as impacts due to natural or anthropic hazards. The aims of this work deals with a new 3d numerical method to simulate an impact on a concrete structure. The combined finite discrete element method fdem proposed by munjiza is an innovative numerical technique to capture progressive damage.
The theory of the fdem can be broken down into the following parts. A combined finitediscrete element simulation of shot. Each discrete element is discretized by its own mesh. Mar 14, 2019 in this paper, simulations are performed to model fracture coalescence processes in granite specimens with preexisting flaws. Therefore, there are several numerical challenges that need to be dealt with effectively. Pdf some aspects of combined finitediscrete element method. The essence of this method is to merge the algorithmic advantages of the dem with those of the finite element method fem. This approach is based on the simulation of a large number of discrete elements that can be in interaction. Finitediscrete element method fdem archives edem simulation. The combined finitediscrete element method is a recently developed numerical method aiming at modeling failing, fracturing and fragmenting solids. Modeling mixed mode fracture of concrete by using the. Finitediscrete element models for assessment and repair of. A discrete element method, also called a distinct element method, is any of a family of numerical methods for computing the motion and effect of a large number of small particles.
A framework for grand scale parallelization of the combined. The combined finite discrete element method fdem fdem was originally developed by munjiza in the early 1990s to simulate the material transition from continuum to discontinuum 33. Review of the hybrid finitediscrete element method fdem. The combined finitediscrete element method pdf free download. One of such combined methods is the combined finite discrete element method developed by ante munjiza 14, 15. In the present study, the combined finite discrete element femdem numerical method is proposed as a tool to assess stability of rock slopes subjected to. Fdem inherits the advantages of fem in describing elastic deformations and the capabilities of dem in capturing discontinuities. Fdem is an innovative numerical technique that combines the advantages of continuumbased modeling approaches and discrete element methods to overcome the inability of these methods to. The combined finite discrete element method can be an advantageous tool for modelling of masonry structures. Rock slope instability phenomena have been often correlated to seismic activity. Modeling simultaneous multiple fracturing using the combined.
Keywords combined finite discrete element method hybrid optimization. Combined finitediscrete element method is intended for the dynamic analysis of a large number of mutually interacting discrete elements, where. Therefore, in combined finite discrete element simulations the number of discrete elements may vary during the collapse process. The finite discrete element method 17, the subject of this paper, was initially developed for. Dec 06, 2012 the purpose of this paper is to present ygeo, a new numerical code for geomechanical applications based on the combined finite discrete element method fdem. Combined finite discrete element method following the work by munjiza and owens earlier work, the combined discrete element method has been further developed to various irregular and deformable particles in many applications including pharmaceutical tableting, 1 packaging and flow simulations, 2 and concrete and impact analysis, 3 and many other applications. Modeling of stickslip behavior in sheared granular fault. There are multiple interactions between particles subjected to large movement during compaction by a tool set. The mode i fracture model was extended for glass by changing the strain softening curve to a. Viennamath provides the symbolic math kernel, viennagrid with viennadata allows for a generic grid handling and quantity storage, while viennacl provides the linear solvers and gpu acceleration. Validation of a threedimensional finite discrete element method using experimental results of the split hopkinson pressure bar test.
Blast simulation in underground mines using the combined. Combined finitediscrete element method for simulation of. Each discrete element is discretized with its own mesh of finite elements and hence its deformability is enabled. Numerical model for confined masonry structures based on. This book is printed on acid free paper responsibly manufactured from. Discrete element method, finite element method, yade, ansys abstract there are many cases where mechanical engineering structures interact with bulk materials, e.
If the physical formulation of the problem is known as a differential equation then the most popular method of its. Several approaches can be used to transform the physical formulation of the problem to its. Abaqus implementation of phase field a phasefield model for brittle fracture is implemented in the commercial finite element software ab. A bridging subdomain is used, the hamiltonian is chosen as a linear combination of discrete and continuum hamiltonians.
The combined finite discrete element method is a relatively new computational tool aimed at problems involving static and or dynamic. Combined finite discrete element method the combined finite discrete element method femdem 3335 is based on the simulation of behaviour of a great number of discrete elements that can be in an interaction. A typical combined finitediscrete element simulation comprises large number thousands or even millions of particles. Based on the combined finite discrete element method fdem, a twodimensional coupled hydrothermal model is proposed.
Introduction to the combined finite discrete element method. Nearly thirty years since its inception, the combined finite discrete element method fdem has made remarkable strides in becoming a mainstream analysis tool within the field of computational. Abstract numerical simulation of hydromechanical couplings by combined discrete element method and finite volumes discrete element modelling dem enables studies of materials by modelling and analysing the phenomena that take place at the scale of their elementary components. Keywords combined finite discrete element method hybrid optimization software suite massively parallel 2d3d multiphysics thm simulations large. With advances in computing power and numerical algorithms for nearest neighbor sorting, it has become possible t. Combined finite discrete element method following the work by munjiza and owen, the combined finite discrete element method has been further developed to various irregular and deformable particles in many applications including pharmaceutical tableting, 8. The potential fracture zone is simulated by the discrete elements des and the other zone by the finite elements fes. Researcharticle modeling simultaneous multiple fracturing using the combined finite discrete element method quanshengliu,1 leisun,1 pingliliu,2 andleichen3 schoolofcivilengineering,wuhanuniversity,wuhan,china. Mar 05, 2018 this paper aims to present a new numerical model for geometric nonlinear analysis of thinshell structures based on a combined finitediscrete element method fdem. The incorporation of deformation kinematics into the discrete element formulation has also led naturally to a combined finite discrete element approach in which the problem is analysed by a combination of the two methods 5,14,16. The combined finitediscrete element method fdem the fdem was originally developed by munjiza in the early 1990s to simulate the transition behavior of material from continuum to discontinuum munjiza, 1992. Space decomposition based parallelization solutions for. Numerical analysis of flyer plate experiments in granite. A combined finite discrete element method fdem is proposed to model the dynamic fracture, fragmentation, and resultant muckpiling process during mining production by blast in underground mine.
A combined finitediscrete element simulation of shot peening. The combined finitediscrete element method fdem proposed by munjiza is an innovative numerical technique to capture progressive damage. A smooth contact algorithm for the combined finite. The combined finite discrete element method fdem code, i. A model for thin shells in the combined finitediscrete. Investigation on the impact damage of glass using the. Recently, an increasing number of models have attempted to combine the advantages of the finite and discrete element methods 1416. Combined finitediscrete element analysis of rock slope.
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