The steel tank imposed various loading conditions on the foundation due to the potential for different liquid levels, pressures within the tank, test conditions, wind loads and earthquakes.
The new tank was planned to be built next to an old tank location, giving non-uniform soil conditions on the site.
Based on field test results, an elastic-plastic soil model was developed and a 2D non-linear finite element model of the soil underneath the foundation was generated.
Non-uniform soil properties were captured in the geotechnical model and the foundation settlement was predicted under the maximum hydrotest condition to ensure settlement limits were not exceeded.
Subsequently the foundation design was verified using a structural finite element model of the concrete slab, which was supported by linear springs calibrated based on the results of the non-linear settlement simulation.