User Area

Software Release History - Version 16

New Facilities and Improvements in LUSAS Version 16.0

Release history

V16.0-3 made available on 13 January 2020

This is an error fix release to correct an urgent software issue preventing the loading of any results file generated since midnight 1st January 2021 into LUSAS Modeller. 

Other error fixes and change requests are included.

• Read the error fix and modification release note for V16.0-3
• Go to the Software Download page

V16.0-2 made available on 9 April 2018

This release is an error fix release for various change requests

• Read the Release Note for full details of all changes made.

Go to Software Download page

V16.0-1 made available on 14 November 2017.

Version 16.0 of LUSAS is a major software release that sees the introduction of steel frame design checking capabilities into LUSAS Modeller and a host of other new features and enhancements to improve general usability and make collaboration between design teams easier.

In addition to steel frame design. other design code-related improvements and enhancements include those for reinforced concrete slab design, traffic load optimisation, design load combinations, and response spectra for various design codes. New worked examples are provided to show how the new design checking and design load combinations facilities are used.

• Analysis-related improvements include the ability to define a cable tuning loadcase in a nonlinear analysis, the introduction of p-delta analysis capabilities, time-dependent prestress, and eigenvalue buckling of stressed structures. A time management facility allows for easy adjustment of the duration of pre-defined construction stages in a staged construction analysis.
• Of many new results processing features, inspection locations, which obtain results for user-defined positions of interest anywhere on a model are of particular note, along with enhanced averaging of results, and improvements to graphing, section slicing and combinations. For printed results, the Print Results Wizard dialog is now used to add chapters of selected loadcase results to a model report. 
• For general modelling, model analysis categories have been introduced. Selection of an analysis category simplifies the user interface to generally only show those menu items and options that are appropriate to the type of model being defined - all helping to enhance the modelling experience and adjust the user interface based on the analysis category. Models can now be merged together allowing two or more people to create separate models of specific parts of a structure simultaneously. BIM import / export is now provided. Section property calculation now supports compound sections, infilled and encased sections, and thin walled arbitrary sections defined solely by lines. Perspective viewing has been introduced, and layout grids and new point, line and surface drawing options speed-up the creation of frame models. Temperature dependent material properties can be defined in LUSAS Modeller for all materials. 
• A range of new 2D and 3D beam elements that provide more functionality have been introduced, with some becoming the default elements of choice for beam and frame analysis.
• An updated user interface provides a more modern look and feel, provides tabs for window selection panels, easier ways to interact with the view windows, and permits multiple selection of treeview data for assignment or deletion purposes.

In summary, this release contains the following enhancements:

Design-related improvements

Design Code Load Combinations

The new Design Combination wizard is used to assign a loadtype to a loadcase, envelope or basic combination for a supported design code. Based on the assignments and settings made, load combinations for those load types are automatically generated by LUSAS Modeller, rather than having to be user-defined one-by-one.

Loadcase / loadtype definition	Combination options	Design combinations created

 Design combinations for the following codes of practice are supported.

• AASHTO 7th Edition
• AS/NZS 1170
• BD21/01
• BD37/01
• CSA-S6-14
• EN1990 (Buildings) Recommended Values
• EN1990 (Buildings) to Irish National Annex
• EN1990 (Buildings) to UK National Annex
• EN1990 (Bridges) Recommended Values
• EN1990 (Bridges) to Irish National Annex
• EN1990 (Bridges) to UK National Annex
• GB 50009 - 2012
• JTG D60-2004

New worked example

• Bridge Design Load Combinations to EN1990 shows the use of the new design load combinations wizard to generate factored design combinations from codes of practice.

RC Slab design to AASHTO LRFD 7th

The RC slab design facility now supports AASHTO LRFD Bridge Design Specifications, 7th Edition, American Association of State Highway and Transportation Officials, 2014.

Material library enhanced

Supplied library materials are now accessed by choosing a material type, for a region or country (when applicable), for design code or standard (when applicable), and for a grade of material (when applicable). Defined material can now be named explicitly, rather than have just a system generated name assigned to it, as in previous versions.

For some materials in some regions a user-defined grade can also be specified. An example of this would be for Concrete, USA, AASHTO LRFD 7th, where a compressive strength, weight, aggregate correction factor, and cement type can be defined.

LUSAS Traffic load optimisation improvements

China JTG D60-2015

When the country name 'China' and Design Code 'JTG D60-2015' is selected on the Vehicle Load Optimisation dialog, traffic loading can now be generated according to China standards:

• JTG D60-2015 General Code for Design of Highways Bridges and Culverts, Chapter 4: Actions.

Denmark - DS/EN 1991-2 DK NA:2015

When the country name 'Denmark' and Design Code 'EN1991-2 Denmark 2015' is selected on the Vehicle Load Optimisation dialog, traffic loading can now be generated according to Denmark standards:

• EN 1991-2 DK NA:2015 DS/EN 1990/A1 DK NA:2015 National Annex to Eurocode 0: Basis of structural design, Annex A2 Applications for Bridges, BaneDanmark/ Vejdirektoratet, 27 Apr 2015.

• DS/EN 1991-2 DK NA:2015 National Annex to Eurocode 1: Actions on structures – Part 2: Traffic load on bridges, BaneDanmark/ Vejdirektoratet, 1 May 2015

• Annex A (Normative) Load Models for Classification and Assessment of Load-carrying Capacity, BaneDanmark/ Vejdirektoratet,

Saudi Arabia - MOMRA Bridges Design Specifications

When the country name 'Saudi Arabia' and the Design code 'MOMRA', is selected on the main Vehicle Load Optimisation dialog, road traffic loading data and parameters can now be specified with reference to MOMRA Bridges Design Specifications.

Sweden TDOK 2013_0267 (NATO Vehicles)

When the country name 'Sweden' and Design code 'TDOK 2013:0267 Military Vehicles' is selected on the main Vehicle Load Optimisation dialog, vehicle loading can now be generated to aid with military load classification of bridges with reference to clauses 2.2.1.5 and 1.3 of TDOK 2013:0267 Version 3.0 - Bärighetsberäkning av broar. UHabb January 2016.

United Kingdom - BS5400-2:1978 loading added

When the country name 'UK' and Design code “BS5400-2:1978” is selected on the Vehicle Load Optimisation dialog, main road traffic loading can now be generated to BS5400-2:1978 Steel, concrete and composite bridges Part 2: Specification for Loads, incorporating Amendment No 4209. British Standards Institution, March 1983.

United Kingdom - BD37/01 loading added

When country “UK” and Design code 'BD37/01' is selected on the main Vehicle Load Optimisation dialog, road traffic loading can now be generated with reference to BD37/01.

United States of America - AASHTO LRFD 7th Edition: Additional State Implementations

When country “USA" and Design code “AASHTO LRFD 7th Ed. - <State>" is selected on the main Vehicle Load Optimisation dialog, road traffic loading can now be generated with reference to the following new implementations:

• Indiana - Indiana Design Manual (2013), Indiana Department of Transportation. The ability to choose state-specific Permit/Owner-specified vehicles is included on the Optional Code Settings dialog.
• Louisiana - LRFD Bridge Design Manual No 2 (June 2016), Department of Transportation and Development, State of Louisiana. The option to apply or not apply magnification factor (LADV-11 loading) is allowed for. When applied, an extra column in the influence dialog is provided to input the magnification factor (MF) for each influence.
• Maine - MaineDOT Bridge Design Guide (March 2014). The ability to choose between “Maine modified live load” or “Normal HL-93 live load”, for the Strength I design case is allowed for on the Optional Code Settings dialog.
• Minnesota - LRFD Bridge Design (May 2016) Minnesota Department of Transportation. The ability to choose between 125% or 110% of HL-93 is provided in the Optional Code Settings dialog. Also the option of 90% of HL-93 (general AASHTO) is given.
• Nevada - NDOT Structures Manual (May 2014). The ability to choose state-specific Permit/Owner-specified vehicles is included on the Optional Code Settings dialog.
• New York - NYSDOT LRFD Bridge Design Specifications, September 2011.

Analysis-related improvements

Nonlinear cable tuning loadcase

The linear cable tuning analysis facility (which calculates load factors for selected lines in a model that represent cables in order to achieve defined target values for various results components) has been supplemented by a nonlinear cable tuning loadcase option. This can be configured by selecting the Analyses> Nonlinear Cable Tuning Loadcase menu item.

Nonlinear cable tuning is for use in nonlinear analyses where geometric, material or boundary condition nonlinearity may exist. It is also used for obtaining an equilibrium state of stressed geometry in existing structures when nonlinear effects are significant.

Unlike linear cable tuning, loadcases do not have to be explicitly selected to be included in a nonlinear cable tuning analysis. Instead, the position of a nonlinear cable tuning loadcase within the Analyses Treeview will dictate which preceding loadcase is used to provide loading data for the cable tuning analysis.

P-Delta analysis

P-Delta analysis has now been implemented for bar, beam, thick and thin shell, and 2D and 3D continuum elements with GNL capability. P-Delta analysis is an approximate geometrically nonlinear (GNL) analysis typically used to take account of the interaction between vertical and horizontal (sway) loading on tall, slender buildings. Vertical constant loads (usually dead loads) are used to form the geometric stiffness (stress stiffened) matrix for the structure; additional live load cases can then be applied and load combinations used to capture the effects of the interaction between lateral and vertical loading.

Time dependent prestress

The multi tendon prestress wizard has been updated for the AASHTO and Eurocodes to provide an option to allow for producing details and results of losses at any time, and for any stage of construction, for supported design codes.

Selection of the new 'Losses based upon time inputs and calculated stresses' option simplifies and avoids the previous need to duplicate particular values for Age, material and geometric attributes that were assigned to the loaded beam. Codified equations are now used to compute creep and shrinkage coefficients that were previously difficult for users to define. Values of "stress at transfer" and "change in stress after transfer" are now computed from assigned model data by solving the model at least twice. In doing this, for an initial solve (the pre-solution), the stress at transfer is assumed to be zero, all time-dependent losses are assumed to be zero, and the prestress loads calculated accordingly. In the second (or subsequent) solve, the stress at transfer is calculated using the eccentricity of each sampling point, and stresses in concrete read from the results of the corresponding loadcase in the first (or previous) solution.

The method of defining prestress prior to this release can still be accessed using the 'Approximate losses, requiring input of estimated stresses' option which allows for producing details and results of short term and long term losses only.

Time management facility

The time management facility provides the means to manage a simple construction schedule and easily adjust the duration of pre-defined construction stages in a staged construction analysis. It can be accessed using the Bridge> Time Management menu item. It can also be accessed from the Tendon Loading Assignment page of the MultipleTendon Prestress Wizard.

It can be used to easily and automatically update the total response time values in nonlinear and transient controls that have been previously specified for each loadcase of a staged construction analysis.

Eigenvalue buckling of stressed structures

The current linear buckling analysis facility has been extended so that it is now possible to define loads that remain constant (dead loads) and those that can vary (live loads) for the computation of a load factor to cause buckling. Linear buckling analysis can now also be carried out after a static nonlinear analysis.

Conversion of loading to mass for eigenvalue analysis

It is now no longer required to manually convert loading to mass if any semi-permanent loading is to be taken into account as part of an eigenvalue analysis. Instead an option on the eigenvalue control dialog can be selected to automatically make allowance for this loading.

Only loading acting in the direction of the vertical axis is considered.

Results related improvements

Inspection Locations

Inspection locations provide the means to obtain results for user-defined positions of interest on a model. Model features can have multiple inspection locations assigned to them. Inspection locations can report results on elements that belong to the assigned feature, and also those elements that belong to topologically connected features. Results can be viewed for all defined inspection locations by selecting the Inspection Locations option from a relevant results dialog, or for individual chosen locations.

Improved averaging of results

Results averaging rules can now be accessed via the Model Properties dialog or the Model Properties control object in the Analyses Treeview. Averaging rules are common for all analyses.

By default in LUSAS Modeller, averaging of results is done for all situations where it is appropriate. Where averaging is inappropriate, multiple values instead of an averaged value are now displayed. The new Averaging Options dialog allows users to state when averaging rules should and should not take place between adjacent pairs of elements in line, surface and volume features.

Enhanced averaging for Direct Method Influence analysis

The former requirement in Version 15 to specify unaveraged or averaged influence results for each participating element when defining an Direct Method Influence attribute has been removed. Instead, for Version 16, this decision will be made automatically. See Model Properties - Options (Averaging Options) dialog.

Influence attributes defined in and assigned to a model in Version 15 are unaffected by this new behaviour because the type of results averaging method that was specified at the time the influence attribute was generated is defined within the attribute.

Selective Results Output

Following results calculation for the whole model, the results written to a results file can be stated to either be for all elements, or now, for a specified subset of elements (those part of a group) within a model. Choosing the latter produces smaller results files more quickly than would be created for a whole model.

Improvement to Graph through 2D facility

A slice section can now be created with reference to a selected line, arc or combined line, optionally specifying that the projected length of the line (in a chosen direction) be used to define the length of slice section line on the model. In addition line sections can be created from intersecting surfaces (advanced use) or at the location of an existing graphed location. When defining the line section by cursor or for lines generated by projection, the section line created will, by default, be drawn in the Utilities layer. This may be used later for repeating the cut if a graph along the same line is required.

A 'Width for corridor averaging' value can optionally be specified to increase the number of results used when creating a graph of slice results in order to avoid localised results concentrations.

Improvements to Beam and shell / slicing resultants

It is now no longer necessary to have to view a model along one of the primary view axes prior to defining a slice location on a model. The slice plane and the orientation of the slice local axes no longer follow the view's rotation axes. Instead, the local yz slice plane of the slice path is used to create the slice planes and this defines the slice local axis.

Multiple beam/shell slice definitions can now be defined in a single model and are saved as utilities within the model. The definitions have been enhanced to provide more spacing options and control over the extent of the model to be sliced.

Results are no longer only displayed immediately after visiting the Slice Resultants Beams and Shells dialog. Now, when slice locations are defined and results are available, results for the slice locations can now be viewed by selecting the Beam/Shell Slice Resultants entity from the results properties dialogs (Contours, Diagrams etc). The time taken to produce beam shell slice results has been reduced.

The Print Results Wizard is now used to select Beam/Shell Slice Resultants of interest for viewing in tabular form or adding to a model report

Combination and Envelope facilities now support User-Defined Results

Beam stresses and results components defined by the User Defined Results facility can now be used as primary components when calculating and viewing results for combinations and envelopes.

Name scoping for User Defined Results

Name scoping (an association of a name to an entity, such as a component or variable) has now been introduced into the User Defined Results facility to help clarify the actual meaning of an included component or variable. Name scoping is optional as long as there is no ambiguity. The range of functions supported by the User Defined Results facility has also been extended.

Print Results Wizard updated

The Print Results Wizard has been updated to consist of a single dialog containing all possible results selections. 

The use of the Print Results Wizard is now consistent with the Graphs and Saved Views facilities with regard to the way in which generated data can be added to reports by either using:

• An Add to Report button on the printed results window that is displayed.
• An Add to Report context menu for the Print Results Wizard entry in the Utilities Treeview

The summary facility now presents its output in a consistent, copy and paste friendly, format.

Loadcase results now generated in a model report using the Print Results Wizard facility

The Print Results Wizard dialog is now used from within the 'Add or Edit a Results Chapter' dialog of the Report facility to add chapters of selected loadcase results to a model report.

Progress bar introduced for Modeller results calculation

A progress bar is now displayed at the bottom of the user interface to show the approximate progress being made by LUSAS Modeller in calculating results for a particular task, such as creating a design envelope, or combination. Each progress step represents one results component being calculated for one constituent loadcase.

Improved storing of Modeller-calculated results

Results for Modeller-calculated results components (such as those calculated for combinations and envelopes, and also for other derived components such as design code-based utilisations, Wood-Amer, user-defined results etc.) can be stored in order to speed-up the initial and subsequent display of those results. This can be done either by setting options to store calculated results in LUSAS Modeller interactively, or by specifying that all or selected results components should always be stored each time a model is solved.

Modelling-related improvements

New Modeller User Interface

The Modeller User Interface has been updated to provide a more modern look and feel, easier ways to interact with the view windows, and now supports multiple selection of treeview data for assignment or deletion purposes.

• View windows now appear with individual tabs for easy selection. These can be dragged and dropped within the interface to create side-by-side views.
• Selection Memory, Selected Items, Cyclable Items, and Visible Items selection panels are also tabbed and can be activated and deactivated individually by using the View > Selection Panels menu item. These panels can now be dragged and dropped to any location on screen, docked with other panels and set to Auto Hide, becoming visible again when the cursor is positioned over their tab identifier. Double-clicking a docked window will isolate it again.
• Context menus for each selection panels can be accessed by right-clicking on the tab heading for each panel.
• Pre-version 16 window behaviour can be reinstated by selecting the Window> Layout> Multiple Documents menu item.

Multiple selection of treeview data

• All Treeviews (with the exception of the Layers Treeview) now support multiple selection of objects in order to carry-out an operation on the items, such as to delete a range of loadcases, or to copy attribute data within the treeview.
• In the Analyses Treeview multiple loading assignments can now be selected to have their load factors changed to one common value at the same time by using the 'Change Load Factor' context menu item.
• Other selection-specific context menus provide options for each treeview entry. Only appropriate context menu options are provided for multiple selected items. For instance a 'Deassign' option may be provided for a particular entry because it would be valid for all selected objects, but an 'Assign' option would be disabled because confusion could occur as the additional assignment data (such as loadcase or analysis) is often required and may conflict.
• Dialogs that show treeview-style check boxes (such as used in the Print Results Wizard dialog) now also support multiple selection.

Model analysis categories introduced

To prevent potential issues such as those arising from mixing incompatible elements, and/or mixing elements with incompatible attributes and options, an analysis category has been introduced, which must be stated for each model. Choosing an analysis category of either 2D Grillage/Plate, 2D Inplane, 2D Axisymmetric, or 3D simplifies the user interface where to generally show only those menu items, dialog settings and selections that are appropriate to the type of model being defined. Selecting an analysis category also defines which startup templates are available for selection.

Models created prior to Version 16 will have an analysis category assigned to them automatically by LUSAS when they are opened (but only where a suitable analysis category can be established based upon the elements present within the model). If an analysis category cannot be assigned by LUSAS automatically (perhaps because a range of now conflicting elements is defined within the model) a dialog will appear asking for an analysis category to be chosen.

Model merge facility

Model merge allows two or more people to create separate models of specific parts of a structure (as for example for different storeys of a building, or different elements of a stadium) and then combine them at a later date into one master model. To do this, a previously saved model can be merged with a currently-loaded model using the File> Model merge... menu item. The resulting dialog provides options to specify how the geometry, attributes, loadcases and groups from the imported model are to be merged with equivalent objects in the currently open model.

BIM / BrIM File import / export

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.

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. The compound section generated can then be assigned to lines in the model and fleshed in the same way as any other geometric attributes.

Concrete infilled and encased steel sections

The Infill/Encased Section Property Calculator is provided in Bridge and Civil & Structural software products only. The following sections are supported:

• 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
  

Chinese steel section library enhanced

Additional cold-drawn, cold-formed, hot-rolled and welded sections are now available for selection from the China section library.

Section property modification / stiffness reduction factors

Properties affecting the analysis stiffness of geometric line section properties can now be reduced or be otherwise modified, whilst leaving their defined dimensions and section properties intact for design calculations. This is done by creating section property modifier attributes for each feature type using the Attributes> Geometric> Section Property Modifier menu item and then assigning a section property modifier to selected features for a particular analysis.

Stiffness reduction factor

A stiffness reduction factor control option has been provided on the deactivation dialog of the birth and death facility. This provides control over the amount that the stiffness matrix is reduced in magnitude when elements are deactivated. It enables different reductions in stiffness to be applied to different deactivated elements such that their relative stiffness is changed, which is useful as a means of controlling the deactivated elements. For example, it may be desirable for the final connecting mesh between two cantilevered-out deck ends to have a lower stiffness reduction factor than the cantilevers whilst deactivated.

Loadcase dependent constraints

Constraints can now be assigned (and be turned 'on' and 'off') on a per-loadcase basis. Previously, they could only be assigned and applied on a per-analysis basis. Amongst many uses, this will enable the control of the positions of inactive nodes in a birth and death analysis.

Section property modification / stiffness reduction factors

Properties affecting the analysis stiffness of geometric line section properties can now be reduced or be otherwise modified, whilst leaving their defined dimensions and section properties intact for design calculations. This is done by creating section property modifier attributes for each feature type using the Attributes> Geometric> Section Property Modifier menu item and then assigning a section property modifier to selected features for a particular analysis.

A stiffness reduction factor control option has been provided on the deactivation dialog of the birth and death facility. This provides control over the amount that the stiffness matrix is reduced in magnitude when elements are deactivated.

Utilities menu simplified / Tools menu added.

The Utilities menu has been reduced to now only generally contain those menu items that create a Utility dataset in the Utilities Treeview. Other items formerly on the Utilities menu now appear on a new Tools menu, alongside any newly introduced menu items.

Temperature dependent material properties

Temperature dependent properties of materials of previously defined, or of new materials can be edited using the context menu item Edit temperature dependence … for a material in the Attributes Treeview.

Thermal loading types rationalised

Thermal loading types have been reviewed and updated.

Internal position of shear springs for joint elements with non-coincident nodes

The internal position(s) of the transverse shear spring(s) for joint elements with non-coincident nodes can now be defined. Parametric distance factors (between 0.0 and 1.0) can be specified to define the position of the shear spring for the local y and z directions. This enhancement allows for import of similar elements from other finite element software.

3D rotated label and diagram text

Label text for lines and surfaces can now be optionally drawn to lie along local line axes, or in the local xy or xz planes.

Similarly, for diagrams, labelled values can now be drawn in the plane of the diagram, as opposed to drawing the values flat to the plane of the screen.

Internal deformed shape of element

LUSAS Solver now computes deformations at each internal calculation point in each beam element, and these may be viewed in LUSAS Modeller as contours or a deformed mesh. This means that the true deformed shape of a line beam can be plotted even if one line mesh division is used to model the beam. For legacy reasons this new option is set 'off' by default.

Changes to the Element Library

New 2D Thick Beam Elements: BMI2 and BMI3

BMI2 and BMI3 are straight and curved thick beam elements in 2D for which shearing deformations are included. The elements can accommodate varying geometric properties along their length. The elements may be used for linear and nonlinear analysis of two dimensional beam, frame and arch structures.

• BMI2 is the element selected by default when a 2D Thick Beam linear element is chosen on the line mesh dialog.
• BMI3 is the element selected by default when a 2D Thick Beam quadratic element is chosen on the line mesh dialog.

New 2D Thick Beam Element with Quadratic Cross-section: BMI2X and BMI3X

BMI2X and BMI3X are straight and curved thick beam elements in 2D for which shearing deformations are included. The elements have a quadrilateral cross section which may vary along the element length. The elements may be used for linear and nonlinear analysis of two dimensional beam, frame and arch structures.

• BMI2X is the element selected by default when a 2D Thick Cross Section Beam linear element is chosen on the line mesh dialog.
• BMI3X is the element selected by default when a 2D Thick Cross Section Beam quadratic element is chosen on the line mesh dialog.

New 2D Plane Strain Beam Elements: BMI2N and BMI3N

BMI2N and BMI3N are straight and curved thick beam elements in 2D for which shearing deformations are included. The element thickness may vary along the length. The element may be used for linear and nonlinear analysis of two dimensional long structures of box girder cross-sections such as tunnel linings and retaining walls for which the plane strain assumption is appropriate. These elements are compatible with 2D plane strain elements.

• BMI2N is the element selected when a 2D Plane Strain Beam linear element is chosen on the line mesh dialog.
• BMI3N is the element selected when a 2D Plane Strain Beam quadratic element is chosen on the line mesh dialog.

New 2D Thick Axisymmetric Shell Elements: BXSI2 and BXSI3

BXSI2 and BXSI3 are straight and curved thick axisymmetric shell elements in 2D for which shearing deformations are included. The element thickness may vary along the length. The elements can be used for analysing linear and nonlinear shell structures which are axisymmetric, e.g. pressure vessels or pipes.

• BXSI2 is now the element selected when a 2D Axisymmetric Thick Shell linear element is chosen on the line mesh dialog.
• BXSI3 is now the element selected when a 2D Axisymmetric Thick Shell quadratic element is chosen on the line mesh dialog.

New 3D Thick Isoparametric Beam Elements with Torsional Warping: BM21W, BMI31W

Straight and curved beam elements in 3D for which shearing deformations and torsional warping are included. The elements can accommodate varying geometric properties along the length. The elements may be used for linear and nonlinear analysis of three dimensional beam, frame and arch structures. BMI21W may also be used as a stiffener for the QTS4 shell element; while BMI31W may be used as a stiffener for the QTS8 shell element.

New 3D Isoparametic Thick Beam Elements with Quadrilateral Cross-Section and Torsional Warping: BMX21W, BMX31W

Straight and curved beam elements in 3D for which shearing deformations and torsional warping are included. The element has a quadrilateral cross section which may vary along the element length. The elements may be used for linear and nonlinear analysis of three dimensional beam, frame and arch structures. BMX21W may also be used as a stiffener for the QTS4 shell element; while BMX31W may be used as a stiffener for the QTS8 shell element.

For more information on all these element types see Element Reference Manual.

Retired Elements

These elements have been retired because their use has been superseded by elements with improved capabilities. Historical models that make use of these elements are not affected and will still solve. Note that all retired elements do not appear for selection on drop lists but can still be accessed by typing the element name into the Line Mesh Attribute dialog.

• BEAM has been retired and replaced by BMI2, which additionally accommodates varying thickness, and geometric or material nonlinearity. BMI3 is also available as a higher order alternative.
• BMS3 has been retired and replaced by BMI21, which additionally accommodates varying thickness, product moment of area input (for non-symmetric sections, strain output, and geometric and material nonlinearity. BMI31 is also available as a higher order alternative.
• BTS3 has been retired and replaced by BMI21, which additionally accommodates varying thickness,and a higher order variation of forces and moments along its length. BMI31 is also available as a higher order alternative.

General changes

LUSAS installation

The LUSAS installation now follows the Windows convention.

Changes affecting LUSAS Programmable Interface (LPI)

All new facilities in Version 16 come with corresponding extensions to the LUSAS Programmable Interface. See LPI documentation for more information.

Modeller Results File caching retired

Modeller Results Files (.mrs) that were created by LUSAS Modeller to save assembled results and speed up the results processing of combinations have been retired and have been replaced in Version 16 with an improved results caching capability. See Combination and Envelope Options for more information.

Bridge load combination wizards for selected design codes retired

The bridge load combination wizards for the BD37/88, BRO and the Korean Highway codes have been retired. A new Design Combination wizard facility has been implemented in their place.

Other user change requests

In addition to the range of new facilities and improvements listed, many user change requests have also been implemented. The originators of all requested changes to the software (some of which are included in the above list of enhancements) that have been incorporated in this release will be notified individually.

Documentation

User manuals

All online and printed documentation has been updated for this new release. Manuals are provided in PDF format as part of any Version 16 software download file, and are also included on the Version 16 software DVD.

New Worked Examples

The following examples have been created to illustrate new facilities added in this release.

• Steel Frame Design to EN 1993-1-1 shows the steps required to prepare a model for a steel frame design check in accordance with EN 1993-1-1, and viewing results of member utilisation both as contour plots and as fully annotated design reports.
• Bridge Design Load Combinations to EN1990 shows the use of the new design load combinations wizard to generate factored design combinations from codes of practice.

Existing worked examples

All examples have been updated to ensure that the examples match changes made to the software and incorporate (where possible) new facilities.

Individual worked examples in PDF format are provided as part of the LUSAS software download file or release CD, as well as being available from the LUSAS User Area.

Other

Potential issues opening PDF files referenced in CHM files

On some PCs, and for certain operating systems, the installation of security updates as released by Microsoft can affect the opening of PDF files from the table of contents panel within the CHM file-based help. Any links to PDF files from within help topic pages may similarly be affected.

If problems are found when attempting to open these files from within the online CHM file supplied please note the following:

• Selected manuals are supplied in PDF format on the installation kit and these are normally installed into the <LUSAS Installation Folder>/Programs/PDF_Manuals folder.
• Workarounds/solutions may be provided by Microsoft during the availability and support of this particular LUSAS software release.

Previous new facilities and improvements in this release

None, this is the first release of Version 16.