Raft & piled-raft analysis

The raft analysis option analyses vertical soil-structure interaction for raft and both vertical and horizontal soil-structure interaction for piles. It provides a means of linking the GSA static analysis of a structural model (typically a raft or piled-raft) with PDisp soil settlement analysis. PDisp is a program which calculates the soil settlements (and stresses if Boussinesq analysis method is used) under the normal and/or shear pressure loads on vertical and/or horizontal planes within the soil. PDisp has been embedded in GSA as the soil settlement analysis engine, so standalone PDisp program is not needed in GSA raft and piled-raft analysis. The data modules in GSA relating to soil properties and analysis can be imported from or exported to the PDisp program.

An alternative modelling option is to create a solid finite element (FE) mesh using the Model > Raft modelling > Create soil FE mesh command. With an FE mesh representing the soil the analysis can be run as a normal static analysis.

See also Raft and piled-raft analysis steps for a how to guide and more information on performing this analysis type.