Vibrations from railways, heavy transport, construction work etc. are a nuisance to many people. An increasing number of laboratories and production facilities are extremely sensitive to even small vibrations, which requires special considerations in foundation design. Waves and wind cause vibrations that have negative effects on the safety and service life of offshore platforms, wind turbines and other fixed structures.
Over the last centuries, more than one million people have died due to earthquakes, and earthquakes have resulted in damage for several hundred billion dollars in many parts of the world. Modern buildings and structures must be dimensioned to tolerate loads of any earthquakes. In 2004, requirements relating to design of structures for earthquake resistance were introduced in Norway. Since 2010, Norway has been required to comply with the rules and regulations in Eurocode 8. The most relevant subjects relating to earthquake in Norway are slope stability, effect on piles, and cyclic response of quick clay.
NGI's specialist expertise
- behaviour of soils and rock material when subjected to vibration and dynamic loading
- soil-structure interaction
- advanced numerical analyses of vibrations and wave propagation in soil and rock
- modelling of soil response to earthquake Waves
- instrumentation, monitoring and analysis of vibration and waves in soil, rock and structures
- natural disasters due to earthquakes
- probabilistic seismic hazard analysis (PSHA)
With our knowledge of soil modelling and the response of loose materials to tremors and dynamic loads, we make analyses and calculations for earthquakes and vibrations and examine the effect of mitigation measures. Typical applications are in buildings, bridges, railways, offshore structures and slopes that are subjected to earthquake and vibration loading.
We have a particular focus on utilising shear waves. Within this field, NGI has developed a seafloor shear wave vibrator. We are also involved in the development of innovative, dynamic monitoring systems for use in the oil and gas industry.
Research and development
We are currently focusing on:
- Behaviour of various types of soils and stability of offshore slopes and pipelines subjected to earthquake loading.
- Response of piles and raking piles during earthquakes
- Modelling of dynamic response of wind turbines and offshore platforms
- Sound-induced vibrations in buildings, and ground influence on propagation of low frequency sound and vibration
- Effect of vibration from blasting on triggering of slides in quick clay, and behaviour of quick clay during earthquakes.
- Design of foundations for facilities sensitive to vibration
- Low frequency vibrations and structural noise from railways, and dynamics of high speed rail tracks
NGI is involved in standardization in the areas of vibration and earthquakes. NGI is a member of the Standards Norway committees on earthquake and vibration. We also chaired the compilation of the Norwegian standards for vibration from land transport and its effect on people, NS8176, and the standards for vibration from blasting and other construction activities, NS8141.
Specialists from NGI teach and supervise students in the area of vibration and earthquakes at NTNU, and give lectures at national and international conferences and professional events.