3 Dimensional Distinct Element Code Users Guide3dec 用户指南1 INTRODUCTION1.1 Overview3DEC is a three-dimensional numerical program based on the distinct element method for discontinuum modeling. The basis for this program is the extensively tested numerical formulation used by the two-dimensional version, UDEC (Itasca 1996). 3DEC simulates the response of discontinuous media (such as a jointed rock mass) subjected to either static or dynamic loading. The discontinuous medium is represented as an assemblage of discrete blocks. The discontinuities are treated as boundary conditions between blocks; large displacements along discontinuities and rotations of blocks are allowed. Individual blocks behave as either rigid or deformable material.3DEC是一个三维数值方案的基础上不连续建模的离散单元法。本方案的基础是广泛的测试数值制定的二维版本，UDEC（1996年艾塔斯卡）所使用的。 3DEC模拟不连续介质（如节理岩体）受到静态或动态负载响应。非连续介质离散块的组合作为代表。被视为块之间的边界条件的不连续性;块沿连续性和旋转的大位移是允许的。个别区块表现为刚性或变形的材料。Deformable blocks are subdivided into a mesh of finite difference elements, and each element responds according to a prescribed linear or nonlinear stress-strain law. The relative motion of the discontinuities is also governed by linear or nonlinear force-displacement relations for movement in both the normal and shear directions. 3DEC has several built-in material behavior models, for both the intact blocks and the discontinuities, that permit the simulation of response representative of discontinuous geologic, or similar, materials. 3DEC is based on a “Lagrangian” calculation scheme that is well-suited to model the large movements and deformations of a blocky system.变形块被分成一个网格的有限差分元素，每个根据订明的线性或非线性应力应变法元素响应。也是由正常和剪切方向运动的线性或非线性力 - 位移关系的相对运动的不连续性。 3DEC有几个内置的，材料的行为模式，完整的块和不连续性，允许响应代表的不连续的地质，或相似，材料模拟。 3DEC是基于一个“拉格朗日”计算计划，是非常适合模型的大动作和一个块状系统的变形。The distinguishing features of 3DEC are summarized below.3DEC的显着特征总结如下。 The rock mass is modeled as a 3D assemblage of rigid or deformable blocks.岩体是仿照作为刚性或变形块的三维组合。 Discontinuities are regarded as distinct boundary interactions between these blocks; joint behavior is prescribed for these interactions.被视为不同的边界相互作用，这些块之间的不连续性，联合行为是对这些相互作用的规定。 Continuous and discontinuous joint patterns can be generated on a statistical basis. A joint structure can be built into the model directly from the geologic mapping.连续和不连续的联合模式可以生成一个统计的基础上。一个联合结构，可以直接从地质测绘模型建成。 3DEC employs an explicit in-time solution algorithm that accommodates both large displacement and rotation and permits time domain calculations.3DEC采用一个明确的时间解决方案可同时大排量和旋转的算法，并允许时域计算。 The graphics facility permits interactive manipulation of 3D objects. In the graphics screen mode, the user can “move” into the model and make regions invisible for better viewing purposes. This allows the user to build the model for a geotechnical analysis and instantly view the 3D representation. This greatly facilitates the generation of 3D models and interpretation of results.图形工具允许操纵3D对象的互动。在图形屏幕模式，用户可以“移动”到模型中，使无形的地区，为更好的视觉效果的目的。这允许用户建立岩土分析模型，并即时查看三维表示。这极大地方便了三维模型的生成和对结果的解释。3DEC also contains the powerful built-in programming language FISH (short for FLACish; FISH was originally developed for our two-dimensional, finite-difference, continuum program FLAC). With FISH, you can write your own functions to extend 3DEC s usefulness. FISH offers a unique capability to 3DEC users who wish to tailor analyses to suit specific needs.3DEC还包含强大的内置编程语言fish（FLACish短;fish原本是为我们的二维，有限差分，连续计划后手）。有fish，你可以写自己的功能扩展3DEC的有效性。fish提供了一个独特的能力，希望度身订造的分析，以满足特定需求的3DEC用户。With the exception of the graphics mode, 3DEC is a command-driven (rather than menu-driven) computer program. Although a menu-driven program is easier to learn for the first time, the command-driven structure in 3DEC offers several advantages when applied in engineering studies.3DEC图形模式的例外，是一个命令驱动（而不是菜单驱动）的计算机程序。虽然一个菜单驱动程序更容易学习，第一次，在3DEC命令驱动结构提供了几个优点，应用工程研究。1. The input “language” is based upon recognizable word commands that allow you to identify the application of each command easily and in a logical fashion (e.g., the BOUNDARY command applies boundary conditions to the model).1.输入“语言”是根据识别的单词的命令，允许你确定每个命令的应用程序很容易和一个符合逻辑的方式（例如，边界命令适用于模型的边界条件）。2. Engineering simulations usually consist of a lengthy sequence of operations e.g., establish in-situ stress, apply loads, excavate tunnel, install support and so on. A series of input commands (from a file or from the keyboard) corresponds closely with the physical sequence that it represents.2.工程模拟通常由一个漫长的操作序列 - 例如，建立在地应力，施加载荷，挖掘隧道，安装支持等。密切与物理顺序，它代表一个系列（从文件或键盘）输入命令对应。3. A 3DEC data file can easily be modified with a text editor. Several data files can be linked to run a number of 3DEC analyses in sequence. This is ideal for performing parameter sensitivity studies.3.3DEC数据的文件可以很容易地使用文本编辑器修改。几个数据文件，可以连接到运行一个序列号3DEC分析。这是理想的执行参数的敏感性研究。4. The word-oriented input files provide an excellent means to keep a documented reco