Seismic Analysis in LimitState:GEO
Since the release of LimitState:GEO 2.0c, seismic analysis has been available to all users, allowing a pseudo static analysis to be undertaken on any problem geometry.
The flexible modelling capability of LimitState:GEO allows complex problems such as quay wall collapse to be straightforwardly modelled as illustrated below:
Pseudo Static Analysis Description
The pseudo static analysis may be formulated as:
- an additional fixed horizontal and/or vertical acceleration within the problem, or
- in such a way that LimitState:GEO returns the value of the acceleration required to trigger instability.
The below figure illustrates the result of applying the latter procedure in determining the horizontal acceleration required to reach a specific active earth pressure on a retaining wall.
The LimitState:GEO result of 0.097g is slightly lower than the result of 0.100g determined using the Mononobe-Okabe equation. The latter is expected to be higher as it is based on a single wedge analysis only. More details are available in the LimitState:GEO manual.
Further information on the seismic modelling capabilities of LimitState:GEO may be found by clicking on one of the following links:
- Manual section on worked examples of modelling with seismic loads
- Explanation of how LimitState:GEO models seismic loads
- How to handle seismic loads within the user interface
For more general information on the modelling capabilities of LimitState:GEO, see this overview, or some examples.