Pushover analysis

• For a pushover analysis the new pushover curve facility will extract the pushover curve from which the ‘performance point’ or ‘target displacement’ can be derived for a supported Code of Practice.
• Related new facilities are provided for defining plastic hinges, plotting contours of hinge status for Immediate Occupancy, Life Safety and Collapse Prevention categories, and for inspecting force-deformation curves for specific hinges.
  

Plastic hinges

• The existing range of interacting and non-interacting hinges has been enhanced for use in pushover analysis. Any number of points can be used to define force-deformation curves. Automatic force-displacement definitions have been included for steel sections. For other materials (e.g. concrete sections), moment-rotations may be computed and introduced manually as absolute values.
  

Plot contours of plastic hinge status

• Plot contours and values of plastic hinge status for Immediate Occupancy, Life Safety and Collapse Prevention categories.
  

Inspect Hinges

• The inspect hinges tool allows you to view he definition of hinges and create new hinge materials by editing existing ones. It shows the actual (absolute values) of the force-deformation curves. If results are available, the response of a specific hinge for a chosen analysis and loadcase can also be inspected.
  

Reinforcement attributes and zones in surfaces

Reinforcement in the top and bottom of a slab or in the faces of a wall is now termed 'surface reinforcement' in LUSAS and is stored as an attribute within the Attributes treeview. Bar reinforcement size, spacing, cover and skew angle of bars can be defined according to project requirements. Cartesian and radial reinforcement arrangements are supported as well as the ability to define extents over which a defined reinforcement layout applies.

• The reinforcement attributes created are subsequently assigned to each surface representing a slab or wall for which the reinforcement layout is applicable. RC slab/wall design attributes need also to be assigned to the appropriate surfaces representing concrete slabs and walls to allow RC Slab/Wall Design calculations to be carried out. Visualisation of x and y reinforcement directions is now provided.
  

• The extents of any defined reinforcement zones may be visualised by accessing the properties dialog of the contour layer and choosing to plot results for 'Reinforcement (model)'. Each selected reinforcement layout assignment / zone will be displayed in a unique colour alongside an associated contour key.
  

Mixed material modelling

• For arbitrary sections, where section properties are dependent on the modular ratios of component materials, these now have the option to be calculated at tabulation time using the material an Arbitrary Section Material attribute assigned along with the geometric attribute. The use of several Arbitrary Section Material Attributes means the section properties can be updated to reflect in-construction and in-service conditions, avoiding the need to define multiple arbitrary sections or re-run the arbitrary section property calculator for each material combination.
• Infill/Encased sections now use the compound material from the assignment for each element and in each loadcase rather than be specified in the geometric attribute. This is now consistent with Bridge Deck (Grillage) material. Different material properties may be assigned in different analyses and loadcases as required to model staged construction processes.
  

Visualised by definition

Visualised by effect on model

Visualised by effect on mesh
(uses different loading)

Vehicle Load Optimisation now supports EN1991-2 LM2 loading

• Group 1b is now available on the Vehicle Load Optimisation Optional Code Settings dialog for Load Model 2. This is for local verifications ("short structural members" to EN1991-2 clause 4.3.1(2)(b)). ψ and beta adjustment factors can be modified using the Advanced options button.
  

Specify initial element temperatures in a thermal analysis

• Initial temperature loading conditions can now be specified for a thermal analysis in a manner that is consistent with a hygro-thermal analysis.
  

Concrete creep and shrinkage to NZS 3101

• Design code 'NZS 3101:2006 – New Zealand Standard – Concrete Structures Standard' is now supported.
  

Time dependent tendon losses for NZS 3101

• Tendon loss calculations (friction, anchorage set) and post-installations losses (elastic shortening, creep and shrinkage of concrete and relaxation of tendon steel) based on time inputs and calculated stresses are now supported for NZS 3101.
  

LUSAS Tank Updates

A 'Concrete (Membrane)' tank option is now available in the concrete tank definition dialog for structural and seismic modelling and assessment. This tank type assumes the liquid is retained by a membrane that transfers all loads directly to the outer concrete wall, with no structural independence of the inner layer.

Hardening soil model

• The hardening soil model with small strain is a multi-surface plasticity model based on the well-known Duncan-Chang hyperbolic model. The hardening soil model is capable of modelling a variety of granular and cohesive soils. Its parameters are obtained directly from standard triaxial and oedometer laboratory tests. An overview example is provided with this release. See the Geotechnical Analysis option for details of all models supported.
  

Smart LPI text editor with Intellisense and improved help

• Links are provided during the LUSAS installation process to optionally install VSCode - the LUSAS recommended editor for LPI script files. If not installed during installation, selecting the menu item File > Script > LPI Editor from within Modeller, or by using the LPI editor toolbar button  will initially take you to a download page and then, after installation, will subsequently launch VSCode as the LPI editor.
• VSCode includes a debugger and language servers capable of providing 'IntelliSense' (a code completion tool that provides a range of features to assist users in finding the correct LUSAS function and understand its arguments) and a huge library of extension modules.

New Grasshopper plugin components

• Point, Activate/deactivate, Volume member, Volume mesh, Loadcase, and Re-order loadcase components have been introduced into the LUSAS plugin for Grasshopper since the release of V22.0 and V23.0.
  

Specify behaviour of variations outside evaluation limits

• For general field, surface function and profile variations, it is now possible to specify the behaviour of a variation outside of its defined limits.