Civil and Structural engineering

Software Tour

Modelling with LUSAS

LUSAS Civil & Structural has an easy to use, associative Modeller for modelling / results processing and a fully integrated Solver that can also be used independently.

LUSAS Modelling of Stockholm Waterfront Conference Centre

Modelling features
  • The user interface is a full native Windows implementation providing an Open Interface to ActiveX compliant Windows software such as Excel, Access, Word and other software.

  • Customisation of menus, toolbars and dialogs (using the LUSAS Programmable Interface) plus the ability to create your own wizards with Visual Basic Scripting provides limitless potential to tailor the software to specific needs.

  • Models are formed of layers where the visibility and properties of each layer can be controlled and accessed via the layer name held in a Layer treeview, one of a number of treeviews used to organise and access model data.

  • Models are created using feature-based geometry methods (points, lines, surfaces and volumes) and CAD import / export is supported. As the model is built up, model features may be grouped together and manipulated to speed up data preparation or to enable parts of the model to be temporarily hidden.

  • Model attributes such as thickness, material, loading and mesh/element type etc. can be named explicitly. Once defined they appear in an attributes treeview ready to be assigned to selected geometry of the model using the "drag and drop" technique.

LUSAS Treeview



  • A model merge facility allows design teams to create separate models of specific parts of a structure and then combine them at a later date into one master model.

  • Automatic meshing with an easy-to-use mesh refinement capability.

  • Built-in associativity, a key feature of the LUSAS Modeller, ensures that if the model geometry is amended, all assigned loadings, supports, mesh and other attributes are automatically updated to suit.

  • Fleshing (the visualisation of assigned thicknesses or section shapes) helps to ensure that the thicknesses and eccentricities of slabs and the orientation of beam members are correctly defined.

  • Datatips reveal useful model information such as assigned properties when the cursor is positioned on top of a geometry feature.

  • The OpenGL implementation provides fast graphical displays. Multiple graphical windows allow simultaneous displays of different parts of the model at different orientations. Powerful cursor selection options and pan, zoom, dynamic rotation and pre-defined views allow for easy viewing and editing of your model.

  • A multi-level undo/redo facility allows quick modelling corrections to be made.

  • Basic geometry data from third-party BIM/BrIM files (*.ifc) can be imported to create a feature-based geometry model in LUSAS. Both BIM/BrIM Structural domain files (*.ifc) and BIM/BrIM Architectural domain files (*.ifc) are supported for export.

  • Detailed on-line dialog help links to additional reference manual material to provide you with the most appropriate level of assistance at all times.

Section libraries and section property calculators

Section libraries and a range of section property calculators help to provide for straightforward modelling of grid/grillage and beam models.

Standard Steel Section Libraries

Steel section libraries include those for use in:

  • Australia

  • Canada

  • China 

  • Europe

  • India

  • Korea

  • New Zealand

  • United Kingdom

  • United States of America

Precast Beam Section Generators

A precast beam section generator calculates section properties for a range of country and region-specific precast concrete beams.

  • United Kingdom Y, YE, TY, TYE, SY, M, UM, and U beam types

  • US AASHTO Type II to VI beams, Florida Bulb T beams

  • Canadian NU Girders. 

An option for including the contribution from a slab is provided so that the section properties required in a grillage model can be obtained.

Standard section property calculators

Section properties for common section shapes such as rectangular, circular, I-shape, T-shape, L-shape, T-Shape and Z-shape sections can be easily calculated.

Riveted and welded sections

These include: riveted I-shape, T-shape, box, trough and cruciform sections, riveted boxes from I sections / channels, I-section with channel, or doubler plates, and welded plate boxes.

Compound section property calculator

Compound sections can be defined from existing library sections. These can be positioned relative to each other and can have differing material properties assigned.

Infilled/ Encased Sections

The Infill/Encased Section Property Calculator supports the following section types:

  • Filled box
  • Filled stiffened box
  • Filled pipe
  • Filled stiffened pipe
  • Encased hollow box - with rectangular or circular encasement
  • Encased filled box - with rectangular or circular encasement
  • Encased hollow pipe - with rectangular or circular encasement
  • Encased filled pipe - with rectangular or circular encasement
  • Encased I-beam - with rectangular or circular encasement
  • Encased Cross I-beam - with rectangular or circular encasement
  • Encased Combined-T-beam - with rectangular or circular encasement

Arbitrary section property calculator

Section property data for any drawn shape or collection of section shapes can be calculated using an arbitrary section property calculator.

Single and Multi-Cell Pre-cast Box Section Property Calculator

This enables section properties of a single or multiple box cross section (with and without voids) to be calculated from user defined dimensional data. The section shapes can be defined either as a simple cross-section or as complex section created from as many lines as are required to form a suitable representation of the true cross-sectional shape.

Single simple box section with void

Multiple complex box section with void

Tapering beams and multiple varying sections

  • Tapering beams can be easily defined by specifying section properties for each end.

  • Multiple varying sections can be defined along a path of lines allowing straightforward building of models for bridges having curved soffits or for arch structures having varying cross-sectional thicknesses.

Definition of a linear tapering beam

Definition of a multiple varying section

Library browser

A library browser permits transfer of attribute data, such as mesh, geometric, material, etc., between models.

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Software Information

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LUSAS is a trademark and trading name of Finite Element Analysis Ltd. Copyright 1982 - 2019. Privacy policy. 
Any modelling and analysis capabilities described on this page are dependent upon the LUSAS software product and version in use. Last modified: May 27, 2020.