An important issue of dynamic analysis is the selection of ground motions. The ground motions should be consistent with the seismic hazard at the site of interest, and should guarantee an unbiased estimate of the engineering demand parameters. This is not easy to achieve due to the uncertainties associated with the hazard analysis, and the limited number of ground motions available in databases. Additionally, engineers cannot perform an unlimited simulations based on nonlinear dynamic analysis in order to decide whether the structure meets the risk-based performance objectives or not.
Information technology can facilitate the use of nonlinear dynamic analysis in practice. For example, it can provide a user-friendly environment for the selection of ground motions. The objective of the project was to develop a multi-tiered web-based system for the selection of the characteristic ground motion records which complements the 3R method. The web-application makes it possible to query ground motion data from various sources, to select hazard-consistent ground motions according to the conditional spectrum approach, and to select a small subset of ground motions (so-called characteristic ground motions) which can be used for risk-based decision making by performing only few nonlinear dynamic analyses.