Projects / Programmes
January 1, 2004
- December 31, 2008
| Code |
Science |
Field |
Subfield |
| 2.01.00 |
Engineering sciences and technologies |
Civil engineering |
|
| Code |
Science |
Field |
| T220 |
Technological sciences |
Civil engineering, hydraulic engineering, offshore technology, soil mechanics |
| T230 |
Technological sciences |
Building construction |
Researchers (26)
Organisations (1)
Significance for science
The research team is well established internationally which is evident from numerous citations of publications, editorship of the most prominent journal in the field of earthquake engineering, the memberships in editorial boards of several international journals and scientific committees of international conferences, as well as the invitations for visiting professorships at eminent universities abroad. Due to formal and informal collaboration with the majority of research centres worldwide the research program was to a great extent coordinated internationally and dealt with some of the most actual problems. We believe that our research results have contributed to the knowledge in the field of earthquake engineering and eventually, at the end, help in diminishing the number of casualties and material damage due to strong earthquakes. The practice-oriented nonlinear N2 method for seismic analysis of structures, developed within the research group, has been widely recognized and applied worldwide. It has been implemented in the European standard Eurocode 8. New results obtained in the research on the extensions of the applicability of the method to the plan-asymmetric (3D) structures and to RC frames with masonry infill, and in research on the implementation of the probabilistic approach represent important achievements in the international space. Within international projects, several pseudo-dynamic and shaking table tests of large-scale prototypes were performed in leading European and USA laboratories. The results have contributed to the development, improvement and calibration of new numerical models. New models enabled a seismic risk study for a whole class of RC prefabricated industrial buildings. In the case of RC structural walls with openings, some structural details used in the Slovenian practice as well as the numerical model for flexural behaviour of structural walls were verified in a shaking table test in Lisbon. This model was used in the benchmark study of the full-scale 21m high structural wall tested on the shaking table in San Diego. Our team won the competition by the best prediction in the academic/research category. The applied model was relatively simple, yet very efficient. In research on the determination of the deformation capacity of rectangular RC columns a nonparametric empirical approach, called the CAE method, was used. The complete force – drift envelope, as well as the hysteretic energy dissipation capacity and the related decrease of the ultimate drift due to cumulative damage were investigated. The research results are important for two reasons. The CAE method has been formulated in a form which can be used for solving different engineering problems based on empirical data. The results obtained for the deformation capacity of RC columns are needed for the seismic assessment of RC structures. The laboratory tests of the RC beams strengthened by applied steel or CFRP plates were the basis for the development and validation of two mathematical FEM models based on fracture mechanics. They can simulate development and distribution of cracks, nonlinearity of materials and fracture development. The simplified model simulates a simple distribution of cracks whereas the more precise model simulates the actual distribution of cracks. Both models are able to simulate the entire response of the tested beams up to fracture. The analyses demonstrate that a reasonably accurate prediction of the behavior of RC structures strengthened by surface applied plates is feasible. The results are important for the design of the strengthening and upgrading of RC structures by external applications of steel and FRP plates which is becoming very popular in seimic regions.
Significance for the country
Seismic resistance of structures and their equipment is extremely important for the safety of the population in Slovenia, as well as for the protection of the material goods and of the cultural heritage. In parallel to the basic research, applied research has been performed. The results have been transferred to the practice by different means. The final research results are the procedures for designing seismic resistant structures (new and existing ones) and equipment. Important results are also the code provisions. The existing N2 method is a constitutive part of the Eurocode 8 (EC8) which is used as the Slovenian code for design of earthquake resistant structures. It is reasonably to assume that the extensions of the N2 method, developed within the research program, will be also implemented in EC8. The research results contribute to the knowledge needed for the preparation of a user manual for EC8. The research on RC structures addresses structural systems which house hundredths of thousands people (apartment and office buildings with structural walls), the majority of industrial buildings and related production (precast industrial buildings), and support the vital communication links (highway viaducts). RC structural walls are the most common structural elements used in the apartment buildings in Slovenia, and RC precast structures are the most common type of industrial buildings. A large number of collapses or even a heavy damage to these structures during earthquakes would be catastrophic. The developed, experimentally verified numerical models and methodologies enabled systematic seismic risk studies for whole groups of such building structures located in Slovenia. For the first time a comprehensive information is available, indicating (in)adequacy of structural detailing. As a result of our research the majority of highway viaducts in Slovenia were designed according the latest research achievements. This will significantly reduce the structural damage during future strong earthquakes, while indirect damage due to the interruption of traffic will be minimized. In the case of the Ločica viaduct seismic isolation was applied for the first time in Slovenia. The project as well as the leading designer of the project obtained the highest reward for structural achievements from the Engineering Chamber of Slovenia. Based on research results, different retrofit technologies were proposed for typical columns in old viaducts which impose a large seismic risk. An innovative semi-active seismic isolator was developed, produced and tested within an EU project. The device will be useful to protect the equipment in the buildings which should operate without interruption after moderate earthquakes (hospitals) and in buildings with precious contents (museums). Increased seismic resistance is extremely important for the survival of the cultural heritage. European Construction Technology Platform (ECTP) is an initiative of the European construction sector gathering about 600 partners with the intention to reach Lisbon's goals. R.Žarnić is the coordinator of one of Focus areas of the ECTP, i.e. the Focus Area Cultural Heritage (FACH). He is also a founder of the Slovenian Construction Technology Platform and of its Research Fund. As a member of the managing team of ECTP he contributed to the development of the basic documents of ECTP that are playing an important role in the creation of EU policies related to the future research financing. Research related to the low intrusive intervention in cultural heritage buildings for upgrading their earthquake resistance appeared in the 2008 call. This has opened opportunities to Slovenian companies to join the international consortia in FP7 proposals. The results of all investigations contribute to an increase of the seismic safety of new and existing structures, to more economical construction and to a better quality of seismic design.
Most important scientific results
Final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Final report,
complete report on dLib.si
