Earthquakes
Earthquake Engineering
The purpose of the earthquake engineering research programme is to gather knowledge regarding earthquake mechanics, earthquake-induced effects, hazard and risk assessment and earthquake resistant design, as well as emergency response. The programme can be divided into the following main parts:
Field measurements
The purpose is to collect earthquake data, especially for large earthquakes. The intention is to improve structural design standards and to establish a basis for risk assessment and risk management. This part of the project can be divided into the following components:
- Acceleration measurements in southern Iceland
- Earthquake measurements in hydroelectric power plants
- Earthquake measurements in dams
- Earthquake measurements in bridges
- Earthquake measurements in buildings
- Earthquake measurements in northern Iceland
Seismic excitation
Emphasis is put on the development of simple models, such as pseudo-velocity spectra, which can be used in structural design. Special focus has been on parametric models, as well as the development of earthquake maps.
System identification of structures. This project focuses on ARX and ARMAX models, natural frequencies and vibration damping. Comparison is also made between actual earthquake responses of structures and responses of finite element models.
Earthquake response of complex structures. Computational methods and software fro non-linear analysis of earthquake response of complex structures is developed. These methods take into account the interaction effect between foundation and the structure, as well as the tree-dimensional wave motion of the earth’s surface during earthquakes.
Risk assessment
Probabilistic methods and risk maps are being developed. The purpose is to enhance the capability to assess risk and estimate the damage caused by earthquakes in Iceland.
Risk analysis of structures in southern Iceland
The purpose is to investigate the safety of structures in southern Iceland with respect to a possible earthquake in the area. This will facilitate estimates of expected damage due to an earthquake.
Seismic risk of power plants
The purpose is to investigate the earthquake resistance of hydroelectric power plants, to estimate possible damage, and make suggestions on how to respond to a possible earthquake.
Earthquake resistance of buried pipelines
The purpose is to estimate earthquake hazard in the specific area where the pipeline is located. The displacements and the resulting loading that is experienced by the pipeline due to an earthquake are estimated by analytic methods, and the extent of possible damage predicted.
Earthquake resistance of structures
The purpose is to develop expert systems that make it possible to predict the earthquake resistance of structures, which
- are being designed
- have already been designed
- have experienced an earthquake
Earthquake-resistant design of buildings
The purpose is to improve currently used methods in earthquake-resistant design of buildings in Iceland.
Methods for transformation of earthquake energy (seismic isolation). The purpose is to develop a computer model for complex structural systems which use energy-dissipating support points. A special emphasis is on the use of lead-rubber bearings to enhance the earthquake resistance of bridges. The structural performance of numerous vital bridges in southern Iceland has been investigated for this purpose.
Design methods and socio-economic optimisation
The purpose is to develop probabilistic methods which specifically account for the Icelandic environment, both with regard to geology and building construction. Methods are being developed for optimal earthquake-resistant design, i.e. methods that account for overall social profit rather than values of individuals or small institutions.
Eurocode 8
Special emphasis is put on the development, testing and implementation of EUROCODE 8. This includes assessment of peak ground acceleration (PGA) maps suited for application with the code, both PGA maps for Iceland, as well as zoning maps for areas of special importance, such as the capital region, which is the most densely populated area in the country. Furthermore, de-aggregation of hazard maps facilitates non-linear seismic analysis of structures.