Projects / Programmes
Mehanika konstrukcij (Slovene)
January 1, 2004
- December 31, 2008
| Code |
Science |
Field |
Subfield |
| 2.05.00 |
Engineering sciences and technologies |
Mechanics |
|
| 2.01.00 |
Engineering sciences and technologies |
Civil engineering |
|
| Code |
Science |
Field |
| T220 |
Technological sciences |
Civil engineering, hydraulic engineering, offshore technology, soil mechanics |
| T210 |
Technological sciences |
Mechanical engineering, hydraulics, vacuum technology, vibration and acoustic engineering |
Researchers (20)
Organisations (2)
Significance for science
The research group was successful in publishing its results in high-quality peer-reviewed international journals and in disseminating knowledge on national and international conferences. We wish to point out here those works that seem to us to undoubtedly contribute to the "development of science". ---Tools for numerical non-linear static and dynamic analysis of space structures. We have proposed a family of accurate, reliable and robust, and computationally efficient spatial beam finite elements, based on the interpolation of strain vectors. The improvement of the present-state beam finite elements has been made possible by introducing and implementating several new ideas, including: the point-wise satisfaction of consistency conditions; inconventional interpolation functions; quaternions; new energy-conserving time-integration scheme; the way the non-linear constitutive equations are solved to improve the global convergence. A parallel work has been focused on the development of a composite planar beam element, where slip at the contact between the beams takes place. They provide tools for a reliable analysis of behaviour of engineering structures, as shortly described in the sequel. ---Behaviour of structures in fire. It is essential to be able to predict behaviour of engineering structures in fire without doing experiments. Our numerical tools described above have been modified to include time-dependent temperature loading and realistic material laws that are capable of behaviour of material during high temperature. A systematic analyses have been performed to assess the effect of a number of parameters on simple structures. ---Composite structures. Here our objective is to assess the effect of slip between the layers of equal or different materials, with the connections being either perfectly or imperfectly glued, welded, nailed or screwed, on ductility and the bearing capacity of the composite structure. Although being small, slip may largely affect ductility. As composite timber structures are prone to delamination, their effect onto the critical load and post-buckling behavior should not be neglected. The delamination often triggers the buckling failure at a considerably reduced force. It is thus very important to study different types of single and multiple delaminations regarding their effects on both buckling and post-buckling behavior. ---Material properties and behaviour in hardening concrete. Here our concern are adiabatic temperature curves due to hydration of cement, the setting time in a cement paste and the variation of strength of concrete with time. We managed to develop a neural networks-based computational algorithm that is capable of predicting adiabatic curves for a rather general concrete mix. The setting time and the increase of strength during initial phase of hardening of concrete depend on various parameters including temperature of concrete. A simple, ultrasonic-based non-destructive procedure to obtain the setting time of cement paste has been developed and validated. The third method combines ultrasonic experiments and artificial neural networks to predict current concrete strength. These new methods are simple to use and are thus not only a scientific achievement. ---Timber strength grading. Simulation methods such as Monte Carlo method must be applied to analyze the accuracy and reliability of strength timber grading. There are several steps that are of a significant scientific value: the generation of sample of non-normally distributed correlated random variables; characteristic value determination in the case of small samples; and the automatization of the grading procedure and determination of optimal goal function for the optimum grading and machine setting determination.
Significance for the country
The period 2004-2008 appears to be successful for the Structural mechanics group particularly in terms of its scientific production. This proves its high scientific level comparable to the level in good international universities. This is of a prime importance for our faculty, students and slovenian universities in keeping pace with the international academic community. The research group follows its own theoretical concepts and combines them with the ideas found in recent literature. The primary aim of the group is the production of its own mathematical models and research computer programs, although commercial computer programs are not fully ignored. Hence it operates as an independent research unit with a profound knowledge of both theory and computational techniques. This is an advantage in solving non-standard professional and scientific problems. The characteristic problems of this kind, also important for Slovenia, are fire safety of structures (e.g. of tunnels), timber strength grading (sawmills), and behaviour of fresh hardening concrete (with regard to the optimal technology of construction of large buildings, e.g. hydro power plants on the river Sava).
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
