Projects / Programmes
January 1, 2009
- December 31, 2014
| 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 |
| Code |
Science |
Field |
| 2.01 |
Engineering and Technology |
Civil engineering |
Researchers (28)
Organisations (1)
Significance for science
The practice-oriented nonlinear N2 method for seismic analysis of structures has been widely recognized and applied worldwide. It has been implemented in the European standard Eurocode 8. The extension of the applicability of this method to the structures with an important higher-mode effect along the height and in the plane represent a significant achievement at the international level and provide the basis for an appropriate modification of the European standard Eurocode 8. By combining the N2 method and the close-form equations for the assessment of the probability of exceedance of selected performance state of structures it was possible to formulate a method for quantitative assessment of the seismic risk of building structures. Quantitative data on the uncertainties related to the seismic assessment of typical reinforced concrete structures were also obtained, taking into account the dispersions of input data related to seismic loading and to the structural model. These data enable the use of the developed method for seismic risk analysis. The method will facilitate the implementation in practice of a new generation of methods based on probabilistic considerations. Methods and tools which can be used for evaluation of seismic risk of existing and new structures were developed and applied to different types of structures. Performance measure can be defined in terms of annual exceedance of a designated limit state, probability of losses given for a given earthquake scenario or, for example, expected annual loss which can serve as a basis for determining insurance premiums. Seismic risk analysis offers the opportunity to introduce new philosophy for design of structures in seismic regions. Research of RC precast structures, conducted in the frame of several European projects, where the collaboration with the main European associations of the precast industry was established, provided several significant scientific results. The complex mechanisms of the seismic response of the main structural system of RC precast structures were investigated in detail. Based on the extensive probabilistic parametric studies the seismic vulnerability and the seismic risk were estimated. The results of these studies had a direct impact on the proposal for important changes of European standards. The mechanisms of the seismic response of links between main structural elements were explained. Completely new procedures for the design of this links were developed, resulting in more economical joints. A special attention was devoted to links between cladding panels and main structural systems. They were typically adopted from the non-seismic regions. Therefore, there were no data about their seismic response at all. The basic mechanisms of their response were defined for the first time. Based on this research, innovative techniques for the seismic protection of cladding panels were developed. European Guidelines for the evaluation and mitigation of seismic risk to cultural heritage assets were prepared in framework of the PERPETUATE project in which we participated as a partner. In the project the displacement-based approach was adopted as the standard method of analysis. A full methodological path consists of: definition of performance limit states (specific for architectural and artistic assets); evaluation of seismic hazard and soil–foundation interaction; construction knowledge; structural modelling and seismic analysis of masonry structures and unmovable artistic assets; verification procedures; rehabilitation decisions and design of strengthening. As an upgrade to the PERPETUATE project outcomes we developed mortars and grouts with lime binder and reactive dolomite aggregate for repair and strengthening applications. They are compatible with original historic materials and are able to maintain adequate strength and durability also in water saturated environment.
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. Within the programme, applicative and pre-normative research was performed in parallel to the basic research. The results have been transferred to the practice by different means. The final research results are the procedures for designing seismic resistant structures and equipment, as well as appropriate computer programmes which facilitate the use of the developed methods. 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 reasonable to assume that the extensions of the N2 method, which were developed within the research program, will also be implemented in EC8. The results of all investigations contribute to an increase of the seismic safety of new and existing structures and to more economical construction. Young researchers have been trained to solve the most difficult technical problems, which will contribute to their successful independent work after the doctorate. The research results will have an impact on the research community, practicing engineers, professional organizations and committees, and code writing bodies. In Slovenia and Europe the predominant share of industrial activities take place in RC precast buildings. Their failure can jeopardize many human lives, and can have enormous economical and catastrophic environmental consequences. Empirical evidence from the recent earthquakes in our immediate vicinity (i.e after the earthquake in Emilia-Romana) demonstrates that the collapse of such buildings or their parts can paralyse the industrial production of the whole regions in Europe for several months. Our research of RC precast buildings considerably contributed to the increased seismic safety of the RC precast buildings and seismic resilience of industrial production in Slovenia/Europe. The results of this research provided solid background for rational design of industrial precast buildings, and measurable proof that appropriate seismic risk level can be achieved with far more economical design. These achievements will hopefully result in important changes of the Eurocode 8 standards, making the precast industry again more competitive. Determination of mechanical characteristics of XPS boards, which are essential for the seismic analysis of modern low energy building structures, where XPS boards are used as a thermal insulation layer beneath the building's foundations, and optimisation of differently composed thermal insulation (TI) foundation sets in order to increase resistance of the sets to shear load, are important for adequate response of low energy building structures when subjected to earthquake loadings. The finding that some of dolomite aggregates react with the certain components of the cementitious binder and thus affect the mechanical properties and volume stability of concrete, and the explained course of the reaction, enable the use of such dolomites for different applications and can thus improve efficiency and the market value of dolomite stone quarries. The knowledge created is and will be incorporated in earthquake engineering courses at the University of Ljubljana and Univerity of Maribor. Experiments on instructional shake table were introduced within course Introduction to civil engineering. The research group and the University of Ljubljana thus became member of the University Consortium on Instructional Shake Tables, which has more than one hundred members including the most prominent such as Stanford University and University of California, Berkeley. Available are dozens of movies showing seismic response of instructional models of structures during earthquakes (http://goo.gl/VraDVK).
Audiovisual sources (1)
Most important scientific results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2009,
2010,
2011,
2012,
2013,
final report,
complete report on dLib.si
