Loading Types and Load Combinations
LUSAS Civil &
Structural provides a comprehensive range of general loading types to
cater for most circumstances. Envelope and load combination facilites
help you get the most from your results.
General load types
- Structural loadings
include gravity, concentrated, distributed, face, temperature,
stress/strain, and beam loads.
- Prescribed loading
options allow initial displacements, velocity or acceleration to
- Discrete loads
distribute a loading pattern over full or partial areas of the
- Load trains can be
created using a compound load facility.
- Thermal loads
describe the temperature or heat input for a thermal analysis.
Structural, prescribed and thermal
loads are feature based loads that are assigned to the model geometry
and are effective over the whole of the feature to which they are
assigned. Discrete loads are feature independent.Variations in loading
can be applied to all feature load types according to the feature on which
they have been assigned.
Single and Multiple Stage Prestress and Post Tensioning
Single and multiple
tendon prestress wizards in LUSAS calculate equivalent nodal loading
due to tendon prestressing or post-tensioning and assign these forces
automatically to the elements within a model. Computation
of tendon forces can be carried out in accordance with various
regional codes including AASHTO, Eurocode, China and others. A
multiple tendon prestress wizard for staged construction analysis
takes into account elastic shortening due to stressing of other
tendons according to the design code used or to user-defined
The ability to input many hundreds of
tendons in one analysis that can be assigned to many hundreds of
loadcases is made easy by the use of the multiple stage prestress
wizard. Through a series of dialogs, the wizard simplifies the
definition of tendon profiles and properties.
- Elastic shortening losses can be
specified for multiple stressing stages – useful for staged
construction. Locally defined tendon profiles can be used anywhere
in the model and any number of times. One very useful feature allows
the tendon profile to be viewed in real-time as it is defined.
Tendon material properties including short and long term losses can
- The tendon can then be easily assigned
to one or more line features on the model and, more importantly, to
one or more loadcases at the same time.
Smart and Code-specific load combination facilities are a key
feature of LUSAS Civil & Structural and allow manual or fully
automated assembly of design load combinations. From these, envelopes,
contour and deflected shape plots, and results graphs can be readily
obtained for any loadcase under consideration.
- Basic load combinations allow for manual
definition of loadcases and load factors.
- The Smart Combinations facility, unique to
LUSAS Civil & Structural, automatically generates
maximum and minimum load combinations from the applied loadings to
take account of adverse and relieving effects, saving time and
reducing the chance of errors.
- When used in conjunction with a design code
template, combinations of load combinations are automatically
created to give maximum and minimum Ultimate or Servicibility
Limit State loadcases.