Tailored to civil engineers working on structural problems such as earthquake analysis with basic non-linearities and dynamics, CivilFEM can dramatically improve the efficiency of the structural design and analysis process, identify better solutions earlier, and reduce the risk of innovative construction processes. Key enabling capabilities include design verification according to international reinforced concrete and structural steel standards, as well as other civil engineering standards, all of which are built in to CivilFEM. Specific civil engineering structural analysis output such as load path history, automatic response spectrum for seismic analysis, and nonlinear time history analysis are fully supported.Model generation is highly efficient because of the library of materials and hot rolled structural steel sections, included in CivilFEM. Highly accurate solutions are possible because all material properties are time-dependent, and allow the definition of true stress-strain diagrams and advanced nonlinear behavior.
GUI in many international languages. The first CivilFEM release supports English, Chinese and Spanish, offering total localization of the interface, menus and dialogues
CivilFEM has a powerful unit conversion system. The user can choose and change any combination of units during each of the pre and post process analysis steps and CivilFEM will change the representation of all units to the desired system. Standard systems are implemented (System International Units, Imperial Units), and units from different systems can be mixed and matched. CivilFEM will convert all units automatically to the user-defined system at any given time. Converting values to different units is as easy as choosing the new unit in the unit’s drop down menu.
CivilFEM powered by Marc makes use of modern multi-core processors to improve the performance and speed of the analysis solution. This possibility gives excellent scalability on multi-core computers and large models.
CivilFEM file importation
CivilFEM can import and export geometry in the main CAD: IGES, Step and DXF. Moreover, the engineer can reuse any CivilFEM created model by importing it using the Import model option. This operation allows creating new analysis from a single model, minimizing the time spent in the modeling process based on the same geometry. The engineer can choose among different importing options, such as coordinate systems, geometry, materials, sections, structural elements, model utils, contacts load groups, boundary conditions and/or initial conditions.
Total automation of the modeling, meshing, solving and post-processing steps can be achieved using CivilFEM’s Python interfacing capability. The user can access every CivilFEM function using the Python programming language, allowing a programmatic approach (macros) to the design process with the added benefits a powerful modern standard language provides. The user can easily enter repetitive geometry using loops or conditionally modify the design based on obtained results. If required, the program can record a python macro with all the user input data, which could be edited and used again later.
Model and selection groups
Several model elements can be grouped together for performing operations on them at once, speeding up the modeling process. Every kind of entity can be grouped in order to organize the model in conceptual units, so the user will be able to easily select all the entities belonging to a group and operate with them.
After solving the model, the engineer often needs to generate a report with the results and design decisions made during the whole process. CivilFEM includes the option to automatically generate such reports. The reports can include any pre-processing or post-processing data/result the user needs, including (but not limited to) geometry entities, materials, sections, structural elements, etc. Post-processing reports can include a combination of nodal, element and/or extreme results.
Scalar and vector parameters
Modern structural design needs a flexible approach. Instead of using fixed numbers for defining the model, CivilFEM provides the right tools to perform parametrized models by means of scalar and vector parameters and mathematical expressions.
CivilFEM supports a variety of analyses, each one tailored to a specific problem. For static load cases, where moving or transient loads are non-existent, a static linear or non-linear analysis can be performed. The results will give a close approximation to reality, using the least amount of computing time.
Linear and non-linear transient analysis
If the user needs to obtain the response of a model over a period of time, CivilFEM provides the option to perform a transient analysis. In this case a time-dependent load is applied and the results will be calculated over a predefined time interval. The user will be able to check the model response over this time interval and analyze the results in any of the calculated time steps. CivilFEM is able to perform an accurate non-linear transient analysis, considering any and/or all non-linearity types available in the software.
The collection of the mode shapes and vibration frequencies of a model is a key part of the design process of any structure. CivilFEM specifically provides a modal analysis option for performing such analysis. The results can be used in a transient, harmonic or spectral case later to analyze amplification effects in certain frequencies, or other modal related effects.
Cyclic loads are a common component of the study cases the engineer needs to analyze, such as motor rotation inside buildings, wind vortexes, pedestrian stepping in walkways or vehicle traffic over bridges. CivilFEM includes a powerful harmonic analysis option where the user can define the cyclic load using load amplitude and phase. The range of frequencies for study and damping can be defined also. CivilFEM will analyze the response of the structure across these frequencies so the engineer will be able to predict amplification or any other harmonic derived problems in the structure.
Spectral seismic analysis
CivilFEM has powerful seismic analysis capabilities. The user can calculate the response of a structure under known spectral excitation, according to international standards. A user response spectrum can be entered in order to obtain the response under particular conditions outside those defined in the standards. Automatic modal and directions and typical seismic combinations are available. The user has the choice of defining the modal analysis like pre-stressed modal analysis as well as the range of frequencies or number of modes to be extracted in the seismic analysis definition. On the other hand, the forces to masses utility allows to convert a set of load groups to added masses, in this way, these forces will be computed like masses in the modal analysis.
The buckling effect behavior of slender elements can be easily carried out using the Buckling analysis option in CivilFEM. The analysis will provide the user with buckling shapes and critical buckling load. CivilFEM Advanced can analyze complex buckling, local buckling and non-linear buckling problems with mixed elements and is not limited to single element buckling calculations.
Large deflections and large strains
CivilFEM is powered by MSC Marc, one of the best non-linear solvers available on the market. These geometric non-linearities combined with the other advanced analysis features of CivilFEM, complex non-linear problems can be readily solved and post-processed inside CivilFEM, giving the user highly accurate results in models with geometric (including non-linear elements and materials in CivilFEM Advanced) non-linearities. Precise stepping and convergence options and algorithms give the analyst total control over the solution process and will result in reduced convergence times.
While performing an analysis, the engineer may need to apply several initial conditions to the model in order to simulate several phenomena or including initial stress conditions to a geotechnical model as it’s usually done with a Cam Clay simulation. CivilFEM provides the option of reloading the initial condition (displacements and stresses) file generated in a preliminary analysis and reuse those initial stresses to perform a new simulation.
The modeling step is where the user spends most of the time during the design process. CivilFEM provides the necessary modeling tools to facilitate this task, so the engineer can perform all the modeling with ease. CivilFEM implements modeling tools for points, curves, surfaces and volumes, besides geometry operations such as extrusions, revolutions and boolean operations. Geometry can be copied, moved, rotated and mirrored as part of the modeling process. Using these tools, the user will be able to model any shape with accuracy and speed.
CAD data exchange
CivilFEM supports different CAD standard formats for importing and exporting geometry: IGES, Step and DXF are supported for importing and exporting. Parasolid format is also available for importing. The engineer can use any external software that supports the mentioned formats for creating the model geometry and use CivilFEM advanced features for the FEM model, solving and post-processing steps.
The user has several options to control the meshing step. Linear or quadratic elements can be selected. For 2D modeling, triangles and quadrangles can be used while the user can choose between tetrahedrons or hexahedrons for a 3D solid. Linear elements are meshed using their own element type that lead to increased accuracy in the calculations of such elements. Meshing can be precisely defined choosing between the available meshing algorithms and control parameters, and the resulting mesh can be checked for congruency using CivilFEM mesh checking utilities.
CivilFEM offers an automatic properties input form where the user can choose from an extensive material library, arranged by code and type. Steel, Concrete, Reinforced Steel and Pre-stressed Steel can be chosen according to the active code or standard. Most common types of Rocks and Soils are available to the user, ranging from igneous, metamorphic and sedimentary rocks to different kinds of soils such as clay, gravel and sand.
In case the user needs total control over the material characteristics, a generic material is available to define all common mechanical properties as well as the material constitutive law, isotropic/orthotropic behavior, material plasticity models and failure criteria (some of these features are available in CivilFEM Advanced only).
Standard beam sections for steel can be selected from a wide range of available types according to several codes and standards choosing the “Steel from library” option. If the needed section is not part of a code or standard, it can be manually defined using the “Steel by plates” wizard. If the section is of a predefined shape such as I, T, L, Channel, Pipe or Box, the “Steel by dimension” or “Concrete” option permits the definition of that kind of section directly entering the dimensions. The engineer can use the capture option to define an arbitrary section selecting a previously generated surface geometry. Furthermore, a useful generic section is available in case the user needs to design a section with a particular set of parameters.
Automatic mobile loads
Moving loads appear constantly in engineering problems. CivilFEM implements moving loads in a very easy and intuitive way, allowing a quick definition of a point moving load along a path. The user can totally define the calculation time, steps and the speed of the moving load. Moving loads will prove very useful in the design of bridges, where these kinds of loads are predominant.
CivilFEM can accurately model the interaction between contacting elements or different parts of the structure. Due to the non-linear nature of contact problems, CivilFEM is able to perform a non-linear contact analysis that will lead to high accuracy results. On the other hand, even if the calculation is complex, the user interface for defining contacts is extremely easy to use. At present, two types of contacts can be chosen: Glue and Touching, depending on the expected behavior of the contacting elements. Glued elements will act as if the elements were stuck together, and touching elements will act as if friction existed between them.
There are certain situations where a rigid or semi-rigid link between independent nodes needs to be created. CivilFEM simulates this behavior using Connections. With the Connections option the user can quickly create a link between a master node and several tied (dependent) nodes and define a tying condition between them. The connection can be created to affect directions and rotations and can be rigid or semi-rigid defined by a coefficient or as a spring.
Path History Results
CivilFEM can plot time-dependent results, where all result types can be plotted against time in a transient analysis or frequency in a harmonic analysis. In a non-linear analysis, force versus deflection, or other combinations can be represented as a detailed graph of the non-linear behavior. This option is very useful for checking the model when it reaches the non-linear state.
Engineering problems usually need to be analyzed under several load combinations. CivilFEM incorporates Combinations, and Envelope options for such cases. Using Combinations, the engineer can combine the defined load cases applying different coefficients to each of them and obtaining a combined load case as a result of the weighted original load cases. Finally, with the Envelope option the user can obtain maximum and minimum values of a group of results, including combination results and/or checking /design results.
If the analyst needs more control over the combined individual results, the Synthetic option provides the means to apply different coefficients to each nodal, element and extreme result to obtain a precise combination of every possible outcome. A new result file will be generated taking into consideration the applied coefficients, so the engineer can quickly review the desired individual combination of parameters.
Structural Codes: Every analysis usually needs to meet the conditions and rules of an existing code or local standard to provide valid results that are suitable for execution. CivilFEM can perform checking and design in a wide variety of the most used international standards. New standards will be added in future releases and on demand:
- Steel codes:
- Eurocode 3
- British Standard 5950
- AISC LRFD 13th edition
- AISC ASD 13th edition
- AISC LRFD 14th edition
- AISC ASD 14th edition
- AASHTO LRFD 2012
- Chinese code GB50017
- Spanish building code: CTE DB SE-A
- Indian Standard 800
- Russian code SP 16-13330
- Concrete codes:
- Eurocode 2
- ACI 318
- Spanish code EHE
- British Standard 8110
- Australian Standard 3600
- Chinese code GB50010
- Brazilian code NBR6118
- Indian Standard 456
- Russian code SP 52-101-03
Springs, dampers, insertions and masses
The user is not restricted to the more common beam, truss, cable, shell and solid elements. CivilFEM provides different types of tools, named Model Utils. Masses, insertions, springs and dampers are available to the user. Mass option models the behavior of a concentrated mass applied over a structural element. With the Damper and Spring option the user can model the appearance of local dampers and elements following either linear or a non-linear law. Insertion model option allows the definition of host bodies and lists of elements to be inserted in the host bodies. A typical case of an insertion is reinforcing steel bars in a concrete solid section.
Joints in structural elements behave differently depending on the conditions imposed by the designer. CivilFEM implements hinges for the cases where no moment is transmitted from one member to the next. Hinges are very easy to include, as every created structural element has a multidirectional hinge property that can be activated at any given time.
Easy and fast management of structural elements is crucial for an efficient definition of the model. CivilFEM integrates a structural element container where the user can easily find, select and modify any structural element of the model. The element type (beam, truss, cable, shell and solid) is clearly visible, so the user can readily find the element. Selecting the element will show all its properties, enabling the user a quick access to the main element parameters, such as meshing, geometry and cross section parameters.