The Examine manual can be found at the link below:
Examine 4.0 Manual
Can the input file and result file from MAP3D be imported into Examine?
No, we currently do not have the ability to read MAP3D files.Can AutoCAD drawings be imported into Examine?
Examine constructs excavation geometry by using skinning and extrusion technology between mine sections. These sections can be imported from AutoCAD. We suggest that users construct the mesh inside the Examine modeler but the program will read edge-connected 3DFACES from AutoCAD.How can DXF file entities be imported?
The DXF import is handled through a utility called dxfgeo found in the utilities folder in the Examine installation directory. There is documentation in this folder. The program is a Command line program and should be run from a DOS prompt. The documentation contains the type of entities supported. The program converts AutoCAD DXF files to Examine GEO files that you can import into the program. Geo files are discussed in the manual and used in the tutorial section.Is it possible to import a model file in DXF format that has been written by Vulcan or Envisage?
As long as the file format is DXF, you should be able to import it into Examine.
How do I check tractions?
The safest way to check is to use an ASCII editor and look directly at the ex3 file. Everything is commented and you should see the numbers that you want to verify. The traction conditions can also be verified using the Shade-Shade-Options-Normals-Pressure option then quickshade the model. The components are colored a bluish color. The magnitude can be verified by looking at the file.Can Examine tabulate the stresses at different locations so that it can be manipulated in a spreadsheet or similar application?
Write a portable data file (.DAT file) using the File-Save File option in the Interpreter. Edit the file using an editor (notepad, wordpad, word etc.) and remove the header information so that all you are left with is the raw NUE (xyz) data. Bring this new file into excel as a space delimited file.How are the ubiquitous joints implemented in Examine?
The ubiquitous joints in Examine are a post-processing facility. The joints are not explicitly modeled and do not effect the stress field. The Interpreter uses the defined orientation and strength properties of the joint to determine whether a joint would slip if it existed at every point that stresses are sampled (thus the term ubiquitous). The joints have an effect on the strength factor but not the stresses or displacements. Please refer to the Examine manual. The program takes a joint, calculates the factor of safety against slip, and compares this to the rock mass factor of safety. The minimum of these is used.
Does Examine handle surface excavations?
Yes, Examine handles surface excavations.Is there a limit to the integer or real ranges that Examine can accept?
The Examine modeler has 5-6 digits of precision. If your coordinates exceed this precision, translate your model to the origin before working on it.Can seismic event location, magnitude and source paramters be imported into the model?
Yes, complete support for the visualization of 3D seismic datasets exists. The program can be used to visualize any special data in conjunction with the stress analysis results.Can I use symmetry?
Symmetry is not supported in Examine.Is there a restriction on the file size or the number of nodes in Examine?
There are no built in limits on the number of nodes or elements that Examine can handle. The number of nodes that can be processed is limited by the amount of disk space you have available. In order to Compute the boundary element matrix you require N*N*9*4 bytes of disk space where N is the number of nodes. The program needs this space to swap the matrix to disk. For example, a 3000 node problem would require 324 MB of disk space to solve.Is Examine suitable for the analysis of near surface excavation?
Examine can be used for near surface excavations. However to ensure the proper modeling and analysis of results, the following should be kept in mind:
Does Examine support the change of element colors when reading and writing to files?
Currently Examine does not support the change of color at the element level when reading and writing files. It does however support the change of color at the component and object level.
To get reasonably accurate results, what sort of element density is required?
The results are accurate right up to the surface of the excavation. But the results are a function of the discretization of the mesh and vary depending on the complexity of the induced stress field. In some cases a coarse mesh can be acceptable, while in others it isn't. The only way to tell is to fine up the mesh. You can do this very easily in Examine by using the Subdiv. Elem/Poly option in the Object Tools and selecting a group of elements with a box to subdivide, then comparing the results from two analyses.What is the software limitation with respect to the number of blocks and the number of mining steps that could be included in a given model? What are the limitations on number of nodes and elements?
Each file contains one mining step. The user must construct a number of files to simulate the excavation sequence. There are capabilities in the program for looking at differential stresses, displacements, and energy, between files. There is no limitation as to the number of elements used to construct your boundary element mesh. There's no built in limitation to the number of elements or nodes that can be solved. In the past, there was a difficulty with versions prior to 4.098, where the maximum file size in MS Windows (2GB) caused problems with the swap file thus limiting to the maximum number of nodes to ~7500. This has since been fixed, so be sure you have the latest update from our website. You must also have adequate hard disk space to solve these large models, so in fact you are limited by the size of your hard disk. Use the Compute3d Stats option in the Analysis Param menu to see the size needed to solve the model. To calculate the required amount of disk space you can also used the following equation: D=N*N*9*4- where,
D = Disk space required in Bytes.
N = Number of Nodes in your problem. This is the number displayed in the lower right corner of the Modeler window beside the ND.
Yes, it is possible to apply tractions to excavation element surfaces.Is it possible to apply liners (beam elements), bolts and cables?
Examine does not handle beams and bolts.What procedure is used for forming excavation geometry?
Excavation geometry is constructed in the modeler through use of skin polylines and extrusions.In Examine, can different boundary (primary) stresses be applied in x-, y-, and z- directions?
Yes, different boundary tractions can be applied to individual elements in any direction you want.Does the "stress path" or the "loading path" of the rock have to be modeled to reasonably represent the stresses induced in the rock mass remaining around the excavations?
The stresses are really only influenced by the current excavation geometry and the stress field. Only programs with yielding material models (plasticity) such as Phase2 account for the stress path. In short, to do a staged excavation in Examine you must look at the geometry of each stage independently.
Why are contours appearing inside an excavation?
In order for the program to contour right up to the excavation surface, the program uses interpolation and extrapolation to compute values inside the excavations. This is why you may see the contours inside the excavations.
You can shade the model to get rid of contours inside excavations.
See the attached document for details on how the Strength Factor is calculated.
Examine can visualize seismic data (event locations, event density) but it does not do seismic analyses, as in dynamic or pseudostatic seismic loads. It uses a 3D boundary element analysis technique, utilizing a single elastic material model.
For more information on the use of Examine for the visualization of seismic data, see Examine Visualization and Meshing - Thesis.
The Eden utility has a help button and read a standards Examine pts file (documented in the manual). The Eden utility is in the Utilities menu of the Examine start menu. Look at the .DAT file documentation in the Reference Manual (pg 111) for a description of how to enter seismic data points.
The Examine DXFGEO converter only supports 3D face and polyline entities. If you have an AutoCAD model which consists of an edge-connected solid made up of 3D faces, it can be imported. However, this is somewhat rare, and most people end up either constructing the model in Examine using polylines, or using Rhino to create the model. In general, Rhino can create a good surface mesh; for more information, see "How to Create a Model in Rhinoceros 4.0 and Import it into Examine" and Tutorial 11.Am I supposed to use an average modulus in Examine?
Examine has a single elastic material model so you can only enter one elastic modulus and one Poisson ratio. The values that you use are up to you. If the moduli are not too different then an average is fine. However, if you are interested in deformation in a certain area, you should be using the modulus in this area. It could be useful to look at deformation using a range of values (spanning from min to max) to get an idea of the influence on deformation and the range of values you might expect. Generally, in a single material model, modulus and Poisson ratio do not greatly affect the stresses, only the deformation.Can Examine be used to determine the safety factor of a mine pillar?
Examine can be used to determine the stresses in a pillar. It is then up to the user to compute a safety factor. There are facilities in the software for defining a safety factor equation for pillar stability.General Modeling Tips
The following tips may be useful when creating a model, or fixing meshing issues, in Examine:
-The ground surface should be identified as a surface using the Locate Surface option in the Object Tools menu. See Tutorial 7 (pg 167) for more information.
-Always run the Object Check (in the Toolbox menu of the Modeler), which will find problems with the mesh.
-In Examine, the mesh edges must all be edge-connected, meaning that all edges must be shared by two elements and two elements only. To get the edges to properly line up, you have to build the polylines correctly. See Tutorial 4 (pg 145) for details.
-In order to skin polylines, the polylines have to have the same number of vertices. In addition, the vertices have to be ordered such that the first vertex on one polyline attaches to the first vertex on the other polyline, the second to the second, and so on.
-If your model is particularly complex, you may find it easier to use a program like Rhino to build your geometry. See "How to Create a Model in Rhinoceros 4.0 and Import it into Examine" and Tutorial 11 for details.
-The most common issue with mining geometry is that the coordinates are usually huge. You need to transform the coordinates closer to the origin as Examine uses only 6 digits of precision.
-You can bring in multiple polylines and skin them within Examine to form excavations.
-Examine can import AutoCAD DXF files containing closed 3D objects formed with 3D faces that are all properly edge connected (not leaky).
Use DStress, which is a utility for looking at differential stresses between two models for the purpose of examining changes in displacement and stress due to staged excavation. The values are computed by subtracting the File1 results from File2. The results file created by DStress is a text file that can be easily read. To see the format, you can look at one of the .res files created by the Examine compute engine.
You can also always manually look at the stresses and displacements on specific cutting planes.