Hi there,
I am applying the earthquake time history as a prescribed displacement at the base of the model. The problem I am encountering when the strong shaking starts is that the side boundaries deform too much - see below. My lower boundary is a compliant base and the side ones are Free Field. I read that extending the model can help. Model currently is about 120m deep by 340m wide. Excavation depth is about 30 metres.
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Dear Boris,
Indeed, the model boundaries seem to be too close to the main area of excavation. For example for deformation analyses we recommend the model boundaries to be more than 1.5 times the excavation wall depth or more than 3 times the excavation bottom depth. For dynamics that requires to be extended even further.
Have you tried extending them further away?
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