Analyses

COMOSYS provides wide range of structural analysis options.

• Linear static analysis
• Nonlinear static analysis
• Modal analysis with Eigen vectors or Ritz vectors
• Response spectrum analysis
• Linear time history analysis
• Nonlinear time history analysis

Element Library

A comprehensive finite element library is a priori for analysis of general structural types. Following finite elements are available in COMOSYS:

• 3D frame element
• 3D truss element
• 3D non-prismatic frame element
• Triangular and quadrilateral thin and thick shell and plate elements
  • Shell elements has 6 DOFs per node and contains in plate rotational DOF.
• Spring elements
• Nonlinear rotational or translational spring elements and truss elements with
  • Bilinear stress-strain relationship with kinematic and isotropic hardening
  • Elastic-perfectly plastic material behavior
  • Elastic tension-only and compression only materials
  • Elastoplastic gap materials

Supershell & Automatic Meshing

When dealing with plate and shell structures, the user does not have to worry about creating compatible finite element meshes; COMOSYS generates triangular and quadrilateral mesh automatically while giving the user the ability to intervene and fine tune the generated mesh. Combined with fast and powerful graphical user interface, modeling arbitrarily complex shell structures is a breeze.

• Automatic triangular meshing
• Automatic quadrilateral meshing
• Adjustable mesh density
• Arbitrary polygonal surfaces
• Surfaces with polygonal or circular holes
• Ability to define special mesh points and mesh lines for controlling nodal point locations on points of lines of interests
• Point and line densities
• Ability to create recessed and raised regions with in surfaces

Loading

Defining structural loads is a tedious and time consuming work. With COMOSYS, be done with loading in a matter of minutes and seconds.

• Automatic floor loading: COMOSYS detects polygonal areas enclosed by frame elements on a user specified plane and creates load carrying objects. Using these objects, user can easily assign arbitrary number of floor loads, change them or remove them. And it is not just limited to floor loads; the same interface can be used to define wind loads, static earthquake loads, etc.
  • Two way / one way load distribution with auto detection feature
  • Not limited to floors. Planes arbitrarily oriented in 3D space are supported
  • Floor manager for easily managing large number of floors/planes
  • Intelligent links between load carrying polygons and loads so that created loads can be modified or deleted
• Automatic conversion of loads to masses for dynamic analysis
• Enforcement of support displacements
• Temperature and temperature gradient loading
• Time dependent loading (sinusoidal, ramp, step functions, ground motions, etc.)
• Loading Fields: COMOSYS provides a novel approach for defining complex surface and body loads using loading fields. Loading fields are scalar or vector valued functions defined over a spatial domain. They can have their own co-ordinate systems too, if required
  • Linear functions
  • Quadratic functions
  • Exponential functions
  • Power functions
• Uniform surface loads
• In addition to uniform surface loading for plate and shell elements, COMOSYS provides additional tools for loading surface elements:
  • Point Loads
  • Line Loads
  • Surface loads over sub-region
  • Finite element mesh automatically adjusts itself according to these points, lines, and sub-regions

Foundations

Foundations can be analyzed separately (with automatically converting superstructure reactions to loads) or together with the superstructure, using finite element method. In either case, a nonlinear analysis option is available with compression-only material behavior, where the springs at the uplifting regions are eliminated automatically.

• Modeling of elastic foundations with compression-only nonlinear springs
• Automatic assignment of nonlinear springs, the stiffness of which are computed according to specified modulus of subgrade reaction
• Ability to solve structure and foundation together
• Tools for quickly assigning wall, surface, and column loads, or automatically transferring loads from superstructure
• Both thin and thick plate formulations

General Purpose Finite Element Analysis

COMOSYS is not a special purpose finite element software that provides tools for only building type structures, but is a general purpose structural analysis software that you can model any type of structure with general purpose finite element modeling tools such as:

• Fast sparse direct solver and subspace iteration solvers
• Unlimited problem size
• Different equation numbering algorithms
• 6 degrees of freedom per node with the ability to disable any combination of these DOFs at the model level
• Ability to change DOF directions via node local coordinate systems
• Nodal lumped masses in addition to element masses
• Multi-DOF constraints such as diaphragm, rigid body, or equal-DOF
  • Rigid diaphragms can be defined on any plane (not only horizontal or vertical)
• Point, line, and surface restraints
• Automatic and manual rigid end-zones
• Force or displacement controlled analysis
• Rotational or translational spring elements with linear or nonlinear material behaviors, including: elastic tension-only, elastic compression-only, elastic perfectly plastic, bilinear with isotropic and kinematic hardening.

Advanced modeling features such as multiple user defined coordinate systems, powerful object snap capabilities, a very fast 3D engine with real-time rotation, translation, and zoom abilities facilitates modeling of very complex structures of all kinds.

Post – Processing

COMOSYS has a variety of post-processing options for assessing analysis results such as:

• Deformed shape plots
• Animation of deformed shape for -time history analyses, which can be viewed live in the COMOSYS
• Force / moment diagrams
• Extensive set of surface element response quantity contour diagrams. These diagrams include:
  • Stress contours
  • Force and moment contours
  • Displacement contours both in node coordinates and surface local coordinates
  • Soil pressure contours
  • Area of steel contours
• Contour diagram values can be read at any point on these surface in a 3d-view.
• Strip moments and shear forces in slabs, walls, and foundations or on any plane you like. The moments and shear forces are converted to and displayed in a coordinate system meaningful to the direction of line.
• Tabular output for different analysis output items (joint displacements, spring forces, element internal forces, etc.)
• Time-history tables and plots of various response quantities
• Text-reports for all response quantities and group sums.
• Ability to view joints uplifted during a foundation analysis in different color.

These commands are backed by the powerful 3D rendering engine. For example you can view deformed shape, contour diagrams, or force-moment diagrams from any angle instantly, and/or change viewing angle, zoom-in or zoom-out during a deformed shape time history animation without interrupting the animation.