1. Seismic behavior of a structure#
1.1. Definitions#
The analysis of the seismic behavior of a structure consists in studying its response to an imposed movement: an acceleration, in its various supports. The imposed acceleration is a time signal \(\gamma (t)\) called an accelerogram (cf. [Figure 1.1-a]).

Figure 1.1-a: Accelerogram LBNS
The seismic movement considered in the calculation is either a real accelerogram known and read by the operator LIRE_FONCTION [U4.32.02] or a synthetic accelerogram calculated directly in the code, for example with the procedure FORMULE [U4.31.05].