Ground-shaking research for Europe
Earthquakes are a major risk in many developed countries. Although the number of victims is decreasing, the costs and consequences are increasing. World-class seismic research infrastructures exist in Japan and the United States, yet extrapolating results to the European and particularly Mediterranean situation is risky business given the differences in building structures. The EU needs an experimental seismic research infrastructure suited to its own needs and interests, not only to help the huge engineering consultancy and services sector remain competitive, but to better protect EU infrastructures and lives. The EU-funded project 'Design study of a European facility for advanced seismic testing' (E-FAST) addressed this pressing issue. The focus was on the incorporation of high-performance and realistically large shaking tables to avoid errors induced by scaling of results. Facility design included two 6 m x 6 m shaking tables, each able to move translationally along all three axes x, y and z, as well as rotationally. These tables accommodate payloads of 100 tonnes each and can operate independently or linked, the latter with either synchronous or asynchronous motion. Another, larger shaking table (11 m x 11 m) has only horizontal motion and accommodated a payload of up to 500 tonnes. In order to support the shaking tables, the design included a so-called reaction mass in the experimental hall to host the tables, pumps and accumulators, and a thick, strong floor slab placed directly on the ground. The latter eliminated the additional cost and complexity of vibration isolation devices. A modular reaction structure enabled the combining of shaking tables and actuators in various configurations. Finally, a large outdoor area accomodated the construction of models that could be moved to the experimental hall via a high-capacity crane bridge. Preliminary experimental and modelling tests of the design have highlighted important future considerations and capabilities. E-FAST has laid the groundwork for an advanced European seismic testing facility. This promises to significantly reduce vulnerability and promote sustainable economic development through both reduced structural and human losses and enhanced technological competitiveness.
