In its original formulation, a rock bolt was modeled as a line. This paper presents a new contact calculating algorithm for contacts between two polyhedra with planar boundaries in the threedimensional discontinuous deformation analysis 3d dda. The output file from matlab code has been converted to pov format file using a third. Latest advances in discontinuous deformation analysis method. In the conventional dda, openclose iteration is used to deal with the contact constraints, which needs to apply or remove the normal or.
This thesis presents an enhanced nodalbased discontinuous deformation analysis ndda based on the coupling of the discontinuous deformation analysis dda and the finite element method fem, for modeling blocky systems, especially for simulating crack propagation in rock mass. Download discontinuous deformation analysis for free. In this paper, extensions of the dda method to simulate the seismic response of a large rock cavern complex are carried out. Beginning with the original work of shi discontinuous deformation analysis. Discontinuous deformation analysis research papers academia. The process of conducting the conventional dda method can be viewed as a process of obtaining the extremum of the potential energy function of the block. This paper briefly discusses the effects discontinuities the terms discontinuities and joints will be used interchangeable throughout the paper have on rock mass. Moreover, continuous yield, buckling and bifurcation analysis of rotating disk with discontinuous yield were studied. Frame3dd frame3dd is a program for the static and dynamic structural analysis of two and threedimensional f. In this study, the contact detection and openclose iteration, as the bottlenecks of dda computing, are reimplemented on graphics processing units gpus. Threedimensional discontinuous deformation analysis 3d dda. The analysis of stress wave propagation through a rock mass is an important issue in rock engineering, and the discontinuous deformation analysis dda method provides an effective tool to solve. Discontinuous deformation analysis is discrete element method useful for simulating the motion of large numbers of individual bodies in independent motion, subject to contact constraints. Research article discontinuous deformation analysis.
Development of discontinuous deformation analysis for dynamic. Investigation of discontinuous deformation analysis for. Discontinuous deformation analysis with potential contact. Shear creep simulation of structural plane of rock mass. The vertextovertex contact analysis in the twodimensional. Large deformation and discontinuous yield analysis of. This thesis presents an enhanced nodalbased discontinuous deformation analysis ndda based on the coupling of the discontinuous deformation analysis dda and the finite element method fem, for modeling blocky systems, especially for simulating crack. Dda is somewhat similar to the finite element method for solving stressdisplacement problems, but accounts for the interaction of independent particles along discontinuities in fractured and jointed rock masses. Is there any software or source code of discontinuous galerkin method.
Discontinuous deformation analysis dda is a type method for resolving. Extension of the discontinuous deformation analysis method to. The 3d reconstruction tool can be used to process the rock mass point cloud data to get the 3d numerical model, which can be used in 3d discontinuous deformation analysis. The dda treat a discontinuous domain as a system of individually deformable blocks with constant stress and strain which move independently without interpenetration.
In this study, a relatively new numerical method called discontinuous deformation analysis dda is selected to model the response of rock mass subjected to dynamic loads. A particlebased model using discontinuous deformation analysis. The advantage of using dda lies in the fact that the actual mode of failure does not have to be assumed a priori, and displacements and velocities are computed as an integral part of the analysis. Metrology uk has been involved with large scale projects for over a decade. In the vertexedge contact, the contact reference edge is clearly and uniquely defined, while the contact reference edge for the vertexvertex contact is not unique, which will. The following example shows a free fall model with 2500 same sized particles against two vertical glasses.
Khan doctor of philosophy department of civil engineering university of toronto 2010 abstract the distinct element method dem and discontinuous deformation analysis dda are the. Threedimensional discontinuous deformation analysis 3d. Discontinuous deformation analysis dda is a type of discrete element method dem originally proposed by shi in 1988. Dda discontinuous deformation analysis originally developed by g. The discontinuous deformation analysis dda is a numerical method for blocky systems 1. Simulating hydraulic fracturing with discontinuous. Buy discontinuous deformation analysis in rock mechanics practice isrm book series 5. Rotating discs are used widely as important structural elements in mechanical engineering. Dda uses an implicit algorithm for simultaneous solution of the equations of equilibrium by minimizing the total potential energy. Discontinuous deformation analysis dda is a type of discrete element method dem. Genhua shi while he was working at the university of california, berkeley, under the supervision of prof. A discontinuous deformation and displacement ddd analysis method is proposed for modelling the rock failure process. The dda simulations have been used in some practical problems.
Parallel computing of discontinuous deformation analysis. In the twodimensional discontinuous deformation analysis dda, contacts can be generalized into three types. Even if you are only dealing with structural analysis, different software solutions will offer different capabilities dr. View discontinuous deformation analysis research papers on academia. However, most existing simulation methods are based on continuum mechanics and hence are unsuitable in the case of large displacements and deformations.
Research article discontinuous deformation analysis coupling with discontinuous galerkin finite element methods for contact simulations yuesun, 1 xiangchufeng, 1 junxiao, 2 andyingwang 2 school of mathematics and statistics, xidian university, xi an, china school of engineering sciences, university of chinese academy of sciences, beijing, china. With the new code, we can simulate how hydraulic fractures initiate and propagate with the fluid injection. Improving performance of mton processing and data redistribution in in transit analysis and visualization. This method combines the rock failure process analysis rfpa method based on finite element method and discontinuous deformation analysis dda method. A new contact potential based threedimensional discontinuous. Discontinuous deformation analysis import from sourceforge doolinntdda. Development of discontinuous deformation analysis for. In this algorithm, all six type contacts in 3d vertextoface, vertextoedge, vertextovertex, facetoface, edgetoedge, and edgetoface are simply. Numerical simulations of the creep characteristics of the structural plane of rock mass are very useful. All three extensions have been implemented into the original dda program of. The numerical, discrete element, discontinuous deformation analysis dda method was developed by dr. Improved dda method based on explicitly solving contact. In recent years, the discontinuous deformation analysis dda 1, 2 has. Discontinuous deformation analysis dda method 25 is a numerical method proposed by shi to simulate the deformation of rock block system cut by the natural discontinuities.
Discontinuous deformation analysis is discrete element method useful for simulating the motion of large numbers of individual bodies in. The 15th and 16th international conference on analysis of discontinuous deformation osaka 2020, tbd 2022. So large deformation and discontinuous yield analysis of rotating disks were analyzed by abaqus. Extension and application of discontinuous deformation. Dda uses an implicit algorithm for simultaneous solution of the equations of equilibrium by minimizing the total potential energy of the blocky rock mass system. I would like to thank rocscience for providing me access to phase 2 software for this research, and drs.
A modified threedimensional discontinuous deformation analysis 3ddda method is derived using fournoded tetrahedral elements to improve the accuracy of current 3ddda algorithm in practical applications. Discrete element approaches are computationally expensive as they involve the interaction of multiple discrete bodies with continuously changing contacts. If the modes of deformation are known a priori then the discontinuous deformation analysis should also be able to analyze deformations to determine material properties or environmental factors, assuming one or the other is known. Review of validation of the discontinuous deformation. Discontinuous deformation analysis dda is a numerical method, similar to the finite element method, for solving stressdisplacement problems, but for a jointed rock mass. Research article discontinuous deformation analysis coupling. Discontinuous deformation analysis coupling with discontinuous. Deformation analysis and structural layout is our business. Research article discontinuous deformation analysis coupling with discontinuous galerkin finite element methods for contact simulations yuesun, 1 xiangchufeng, 1 junxiao, 2 andyingwang 2 school of mathematics and statistics, xidian university, xi an, china.
The program computes water pressure and seepage throughout the rock mass of interest. Investigation of discontinuous deformation analysis for application in jointed rock masses mohammad s. Presentation mode open print download current view. Github is home to over 40 million developers working together to host and. Discontinuous deformation analysis research papers. Discontinuous deformation analysis browse files at. Dda is typically formulated as a workenergy method, and can be derived using the principle of minimum potential energy or by using hamiltons principle. Pdf discontinuous deformation analysis in rock engineering. Today, we have ten software solutions to help with all aspects of rock slope analysis, from the statistical analysis of rockfalls and rock topples to limit equilibrium and finite element slope stability analysis and much more. Over the last decade, researchers in the discontinuous deformation analysis dda community have dedicated a great deal of effort to document the accuracy of the method by performing validation studies. The discontinuous deformation analysis method proposed by genhua is a discrete one and has a significant advantage when simulating the contacting problem of blocks. Discontinuous deformation analysis dda is a powerful tool for handling block systems and treats an edgetoedge contact as two vertextoedge contacts with a couple of normal and shear springs. This paper presents a modified method of discontinuous deformation analysis dda. In this paper, we target this problem with discontinuous deformation analysis dda.
Twodimensional dda was published in 1993 and threed. Finding the right computeraided engineering cae software to fit your needs isnt an easy task. Discontinuous deformation analysis in rock mechanics practice. The discontinuous deformation analysis method proposed by genhua is a discrete one and has a significant advantage when simulating the. Extensions of discontinuous deformation analysis for jointed rock. Frame3dd frame3dd is a program for the static and dynamic structural analysis of two and threedimensional f discontinuous deformation analysis free download sourceforge. Dec 12, 2010 the following example shows a free fall model with 2500 same sized particles against two vertical glasses. A software with gui for key block theory, developed by. The practical modelling of discontinuous rock masses with. With many people contributing to its development and application, the original twodimensional dda is well developed in terms of both theory and computer coding. I am trying to modify a cfd model applying the dg method, its too difficult and i hope there are some programs that i can. Jan 01, 2016 this paper proposes an improved dda method based on explicitly solving contact constraints to improve the convergence in the implicit openclose iteration of discontinuous deformation analysis. Discontinuous deformation analysisa new numerical model for the statics and dynamics of block systems.
The vertextovertex contact analysis in the twodimensional discontinuous deformation analysis. The discontinuous deformation analysis dda method calculates large deformations and discontinuous problems using timestep solving and provides an effective tool for analyzing the seismic response of rock mass engineering. Latest advances in discontinuous deformation analysis. Is there any software or source code of discontinuous. Discontinuous deformation analysis is a type of discrete element method originally proposed by shi in 1988. A particlebased model using discontinuous deformation. The distinct element method dem and discontinuous deformation analysis dda are the two most commonly used discrete element methods in rock mechanics. Extension of the discontinuous deformation analysis method. Rfpa is used to simulate crack initiation, propagation and coalescence processes of rock during the small deformation. Slope stability analyses include static and dynamic, analytical or empirical methods to evaluate the stability of earth and rockfill dams, embankments. Dda is somewhat similar to the finite element method for solving stressdisplacement problems, but accounts for the interaction of independent particles blocks along discontinuities in fractured and jointed rock masses. Discontinuous deformation analysis is discrete element method useful for simulating the motion of large numbers of individual bodies in discontinuous deformation analysis browse files at. Discontinuous deformation analysis is discrete element method useful for simulating the motion of large.
A novel coupling scheme is presented to combine the discontinuous deformation analysis dda and the interior penalty galerkin ipg method for the modeling of contacts. Our experience in engineering analysis and root cause is our greatest asset and provide us with the understanding of structural systems and potential failures. Discontinuous deformation analysis conference osti. The threedimensional discontinuous deformation analysis 3ddda method was developed for the deformation simulation of rock block system cut by the natural discontinuities in rock mass engineering. These produce opening and slip between blocks along the discontinuities. Thus, with the improvement of hardware and software, it becomes possible to calculate the tidal deformation of a discontinuous earth. Discrete element method dem and discontinuous deformation analysis dda surpassed the fem as the tools of choice for modelling blocky rock masses. Discontinuous deformation analysis in rock mechanics. This paper proposes an improved dda method based on explicitly solving contact constraints to improve the convergence in the implicit openclose iteration of discontinuous deformation analysis. Kinematics and discontinuous deformation analysis of.
This tool contains many functions, such as filtering and plane detection, and many algorithms are proposed by the researchers of engineering computing center, university of chinese academy of sciences. In order to obtain an optimal structural design, it is necessary to estimate the angular velocity and the stress distribution of a rotating disc in fully plastic state. The analysis of rock slopes was central to the founding of rocscience over 20 years ago. Shear creep simulation of structural plane of rock mass based.
Rather than attempting to analyze such deformations with a mathematical model. This paper contains a summary of more than 100 published and unpublished validation studies which comprise the body of dda validation information to which the. Commission on discontinuous deformation analysis dda isrm. In conventional discontinuous deformation analysis dda, the procedure called openclose iteration is adopted to enforce the contact condition, which needs to repeatedly fix and remove the artificial springs between blocks in contact to determine real contact states. Slope stability refers to the condition of inclined soil or rock slopes to withstand or undergo movement. Discontinuous deformation and displacement analysis.
Twodimensional dda was published in 1993 and threedimensional dda in 2001. Discontinuous deformation analysis enriched by the bonding block. Discontinuous deformation analysis dda is introduced as a technique that allows a realistic incorporation of kinematics in routine analyses. The stability condition of slopes is a subject of study and research in soil mechanics, geotechnical engineering and engineering geology.
Discontinuous deformation analysis with potential contact forces. The performance of discontinuous deformation analysis dda needs to be improved for largescale analysis. Apr 02, 20 download discontinuous deformation analysis for free. Some modifications to the process of discontinuous deformation. Rfpa is used to simulate crack initiation, propagation and coalescence processes of rock during the small. Discontinuous deformation analysis dda is a numerical method, similar to the finite element method, for solving stressdisplacement. The simultaneous equilibrium equations are assembled in a mixed strategy, where the entries are derived from both discontinuous galerkin variational formulations and the strain energies of dda contact springs.
Implementation of the finite element method in the threedimensional discontinuous deformation analysis 3ddda. Jan cervenka, founder of cervenka consulting, explains that there are no general capabilities an engineering firm needs in a cae software. In this brief introduction to the method, we will derive the underlying formulas and report on the uniqueness of the. The discontinuous deformation analysis dda has been extensively applied in. In this study, we combined the viscoelastic rheological model of burgers with the discontinuous deformation analysis dda method.
778 1352 803 603 802 706 306 1008 214 519 566 1022 1397 1263 566 930 398 198 1606 274 1630 1028 1149 595 405 428 1321 237 357 202 1280 369 379 988