The research team is very active in the application of the research results. The knowledge has been applied in the case of many specific projects. However, a single application is typically limited to only one or few structures. When a standard (in particular European standard) is improved, the benefit is multiplied many times. Therefore we consider the active participation of the research team members in the development of Eurocodes (in particular EC8 – Design of seismic resistant structures) and in the implementation of Eurocodes in Slovenia as one of the key results. We shall stress once again that Slovenia was the first country which adopted Eurocodes standards as a National code. The research team importantly contributed to this. Based on this experience, several members were invited to participate at the development of the new versions of Eurocodes. On the highest level, are the representatives of Slovenia in - CEN/TC250/SC8 - Design of earthquake resistant structures (Peter Fajfar) and - CEN/TC 250/SC 11 – Structural Glass (Roko Žarnić) Several members are active in working groups: CEN/TC250/SC8/WG2 (Roko Žarnić) CEN/TC250/SC8/WG4 (Peter Fajfar) CEN/TC250/SC6/WG1 (Vlatko Bosiljkov) and in project teams: CEN/TC250/SC8/PT1 (Matjaž Dolšek) CEN/TC250/SC8/PT3 (Tatjana Isaković) All of them, as well as Violeta Bokan Bosiljkov and Matej Fischinger are active in the committees of the Slovenian standards SIST. Tatjana Isaković is the president of the SIST Technical Committee for structures.
F.31 Development of standards
Most research results of the team contribute directly or indirectly to the development od the standards for design. This result shows one of the specific contributions. These are the guidelines for the design of the specific connections between the precast cladding panels and the structure. These connections were designed (if they were at all) for the out-of-plane action. But, as it was described in the previous section, they were never designed for the in-plane action. Actually, the complex 3D interaction is a complex mechanism, which the designers were not able to address. However, the performance and safety of the cladding systems depends predominately on these connections. The fact that many different types of connections are used in the design practice further complicates the problem. Therefore, the design guidelines, procedures and formulas were prepared for the most typical connections used in Europe. The document was published in the European Joint Research Centre technical report. Activities are going on to adopt parts of these rules in Eurocode 8.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 7584097For many years, the research group has successfully collaborated with the NPP Krško, GEN group, Slovenian Nuclear Safety Administration and other stakeholders to addressing the problems associated with the seismic safety of nuclear installations and their equipment. In 2016, we performed an independent review of the seismic analysis for reconstruction of the NPP dam. In addition to the basic seismic analysis, we have also examined the control seismic analysis of NPP dam by ACI standard. We have found a number of shortcomings. In addition, a study on the impact of the modelling of rigid sections on the seismic demand parameters of pillars of the NPP dam was performed. Within the framework of the project documentation, it was found that the reinforcement ratio in the dam is low. For this reason, it was necessary that the dam was treated as unreinforced concrete gravity dam. The checks of the capacity of structural components were therefore carried out on the basis of control of the maximum tensile stresses. The dam was eventually reconstructed in such a way that the dilated pillar in the middle of the dam was connected to the remaining columns. Therefore, all columns of the left and right sides of the dam were connected to each other, while the dilation at the middle pillar was maintained. This solution allows the transfer of forces from dilated pillar to other parts of the structure.
D.06 Final report on a foreign/international project
COBISS.SI-ID: 7494753Academy of Music of Univerisity of Ljubljana is situated in one of the most prominent palace in Ljubljana’s city centre. The palace Kazina was built in the mid XIX c. and since than it has been in use and is in process to be declared as National Monument (NM). Prior analysis extensive on-site and laboratory testing on structure and built materials was performed. Following the requirements of new owners, architects as well as representatives from the Institute for the protection of cultural heritage of Slovenia (ZVKDS), assessment and redesign of the building were performed. Seismic assessment provided both through non-linear pushover method and with kinematic methods (new for Slovenian design practice) showed that the palace in its current condition fulfil 20% of seismic demand according to EC8-1 and EC8-3 provisions. Major problem represents the big Hall in the first floor of Eastern wing of the Palace that provoke torsional effect. For the purpose of design of re-strengthening measures three scenarios were considered: i) Kazina is NM and solving premature failure of big Hall and out-of-plane failure of facades (35% resistance), ii) Kazina is NM and more severe strengthening measures introduced but still in accordance with ZVKDS requirements (60% resistance) and iii) extensive strengthening for obtaining all demands according to EC8-1 and EC8-3 provisions.
F.17 Transfer of existing technologies, know-how, methods and procedures into practice
COBISS.SI-ID: 7932769The research group at the Faculty of Civil and Geodetic Engineering at the University of Ljubljana has been for many years engaged in research in the field of seismic resistance of buildings and civil engineering structures. One of the recognitions for the results achieved is the Zois Award for lifetime achievements, which was won by the past group leader. This achievement was in 2016 selected as one of the five achievements in the field of engineering, which were presented in the framework of the ARRS project Excellent in Science. Research of the team is fundamental. Its ultimate goal is to develop methods of analysis which can be easily used in practice, but nevertheless yield appropriately accurate results. The most notable result is the so-called N2 method, which can quite reliably simulate the behaviour of building structures during strong earthquakes. The method represents a combination of a nonlinear static analysis of the model of the structure and a dynamic analysis of a simplified model using inelastic response spectra. The method is included in the European standard for earthquake-resistant construction Eurocode 8.
B.04 Guest lecture
COBISS.SI-ID: 7951201