After a year of development and testing, we are proud to announce the release of LARSA 4D and the LARSA Section Composer version 7.01, featuring significant improvements to both the analytical and user interface sides of the LARSA software package. Details on the changes can be found below. It is very important to read the section "Important Data Changes and Bugs Fixed", especially if you will be loading an existing project into the new version.

This is the first major official release since version 7.00.02 was released some time ago. Several critical bugs have been fixed, and many new features are available, including compound element forces, influence surface automatic lane placement, and automatic load combinations for staged construction analysis results.

The 7.00 line of LARSA 4D has been discontinued, and we strongly urge all users to upgrade to version 7.01 at their earliest convenience. Before loading an existing project file in the new version, please back up the file. Additionally, bear in mind that because projects saved in new versions of the software cannot be opened in older versions, all engineers working on your project should upgrade to the latest version of LARSA 4D at once.

Improvements to the LARSA 4D software are driven by user feedback, and we look forward to continuing to work with you to respond to your evolving engineering needs.

In Staged Construction Analysis, "extracted" results for class-based result reporting misclassify forces in the structure due to removing supports and deconstructing elements, including them in the load class category "None". We are already working on addressing this limitation.

Influence surfaces minimum back-to-front spacing of vehicles sometimes used a different spacing than what was specified. For models with transverse increments larger than longitudinal (forward) increments, more conservative results may have been reported. In cases with smaller transverse increments than longitudinal, it is possible that less conservative results were reported.

Influence surface lane loads are now entered in load per linear length, rather than per area. When loading an existing file into the new version of LARSA 4D, ensure that the lane load magnitude has been converted correctly.

In Staged Construction Analysis, when the "include geometric nonlinearity" option is off, the effects of large displacement of beams were still being included, but now they are assumed to be small, as in the linear analysis, and are ignored. This does completely remove the effect of geometric nonlinearity, and this reduces the number of iterations needed for convergence when geometric nonlinearity is not required. When the "include geometric nonlinearity" option is checked, all geometric nonlinearity continues to be taken into account. Both options include material nonlinearity if it is present in the model.

In the stresses spreadsheet, Maximum ABS Total Stress was computed incorrectly for Linear Result Combinations and Extreme Effect Groups.

Composite material sections had self-weight computed incorrectly based on an adjusted composite area. A new adjusted weight area value is computed for composite sections.

Graphical stress diagrams for maximum tension and maximum compression would sometimes only show the maximum for the whole member along the length of the member, rather than a station-by-station maximum.

Influence line/surface lane loads had a unit conversion error in some circumstances, and when loading more trucks than can fit on the model (as in the IRC code), it was possible that trucks were placed in overlapping positions.

In the Staged Construction Analysis, automatic self weight can now be applied multiple times for elements. If an element is "constructed" multiple times, self weight will be added again for each construction step in which the element is constructed and a self-weight load case is specified.

Compound Element Forces: Select multiple members and plates and activate this new graphical and numeric results tool to see the combined, transformed forces about the centroid of the selected elements along either the global x-axis or a bridge path coordinate system.

Transverse Shear Forces (Qx & Qy) for plate bending is reported both numerically and graphically

Influence Surfaces have been extended so that the locations of one or more design lanes on a single LARSA "lane" definition are automatically found. The design lane width, margin, and number of vehicles per lane can now be specified.

Temperature gradient application applied to unsymmetrical sections is now supported.

Member End Sections: This new command from the Tools menu lets you inspect the computed properties of nonprismatic sections at member ends within a span.

Influence Coefficients View can now be used to see influence results for displacements and reactions.

The Member End Forces in Global Directions spreadsheet can now be used to report member end forces in joint displacement UCS directions.

A new Influence Analysis Post-Analysis Optimization step speeds up access to influence-based results later on.

Factors for creep, shrinkage, and relaxation can now be entered.

It is now possible to set an option in Extreme Effect Groups to allow the reporting of positive minimums or negative maximums.

The moment curvature element has been improved to handle softening, which is represented by a non-positive-definite stiffness matrix.

When looking at graphical results, putting the mouse over elements now shows the corresponding numeric results in the status bar.

New "measure" tool to graphically measure the distance between two points

New Loading Matrix for Linear Result Combinations from Results > Organize Cases.

Linear Result Combinations can now combine extracted class-based results and incremental results from other result cases.

The Auto Load Combinations tool can now be used with Staged Construction Analysis results to create code-based combinations.

A new Tendon Editor is included for the first time in LARSA 4D, which shows tendons in plan, side, and cross-section views. As it is a new feature, the Tendon Editor is considered to have a preview status.

It is now possible to select many tendons in the Model Data Explorer at once and perform operations on all of them, such as the new Translate Y/Z commands.

The transformation and generation tools now copy lanes and tendons along with other geometry.

Fixes for influence surfaces when plate local axes are not in the same direction.

The option for where to save analysis results now actually allows the old 6.xx method to be used (putting results in the same directory as the LAR file), and there is a new option to use a "projectname.out" directory path.

The kilogram-force unit now works.

The sign convention for tendon primary and secondary moments and for tendon results at member ends were not correct.

Various steel design bug fixes.

After a moving load scenario within Staged Construction Analysis, time-dependent effects were no longer calculated.

Ability to have multiple moving load scenarios within a single construction step.

Improved geometric nonlinearity for plate/shell elements.

Improved cable post-tensioning when lowering the cable force and other fixes for cable post-tensioning.

Extreme effect groups would choose the most extreme case before applying any specified factors. Now the factors are applied first and the most extreme is found after.

Influence setup load cases are now created in a new Influence Loads spreadsheet, instead of with other standard moving loads.

The align plate local axes tool now aligns both the x- and z-axes, besides just the z-axis.

Structure Groups spreadsheets now allow modifying elements in the group, as well as adding and removing elements from the group.

Enveloping steel design result cases and steel design of linear result combinations and extreme effect groups now works.

Various bug fixes for graphics, Select Special (which now allows geometry-based filters while viewing results), spreadsheets, construction grids, meshing and span meshing, breaking members to existing joints, Advanced Draw (breaking members), and Structure Groups.

Steel design operates on only selected members now, and fixes were made for tube sections.

Improvement to Cable Sag input.

Round-off problems in the Model Data Explorer fixed.

Tendon and lane ID numbers can now be turned on and off in the graphics Show window.

Drawing spans now works by clicking one-by-one on the members that make up the span.

Break plates now distributes plate point loads to the new elements properly

Bug fixes for accessing results through macros, which would return results for the wrong entities

Lane span break markers for AASHTO LFD influence point loading were displayed at the wrong positions in the lane graphics view that options with the path spreadsheet. The main graphics window displayed them correctly.

Plate stress graphical view was not working with incremental and class-based extracted view.

Speed improvements, including a major speed improvement to the torsion constant calculation.

There is a new equation editor to enter commonly used equation types.

Added reverse shape points order, shift points backwards/forward, flip horizontal, flip vertical tools, and some undo/redo bugs were fixed.

Radius of gyration y and z were interchanged.

Built-in templates had stress points in the wrong order.

Bug fixes for DXF import, Duplicate Section

More than one instance of LARSA 4D can now be open at a time.

An MSI installer is now available.

A library called "ldata2" that caused installation problems on some computers has been removed from the program.

A regional settings problem involving bridge path coordinate systems was resolved.

Some font problems running LARSA4D on Windows Vista are resolved.