This example demonstrates the natural frequency of a long five-story building when subjected to free vibration and earthquake loading.
The building consists of 5 floors and a basement. It is 10 m wide and 17 m high including the basement. The total height from the ground level is 5 x 3 m = 15 m and the basement is 2 m deep. A value of 5 kN/m2 is taken as the weight of the floors and the walls. The building is constructed on a clay layer of 15 m depth underlayed by a deep sand layer. In the model, 25 m of the sand layer will be considered.
This exercise requires a PLAXIS 3D Ultimate license for Dynamics features.
The attached *.p3dlog file contains all the commands to generate the model. With a Bentley Geotechnical SELECT Entitlement [GSE] licence, you can use the commands runner to open the *.p3dlog file and to execute all commands in one go, see also this instruction.
PLAXIS 3D Tutorial 08: Dynamic analysis of a generator on an elastic foundation [Tutorials]
PLAXIS 2D Tutorial 15: Free vibration and earthquake analysis of a building [Tutorials]
How to activate a dynamic load [Tips and Tricks]