1021. A fully generalised approach to modelling fire response of steel-RC composite structuresJerneja Kolšek Češarek, Miran Saje, Igor Planinc, Tomaž Hozjan, 2014, izvirni znanstveni članek Povzetek: A three-step model for the performance-based numerical simulations of the fire response of steel–RC two-layered beam-like composite structures is presented and validated. The first step consists of the determination of the evolution of temperatures in the structure׳s surroundings. Moisture and the heat transfer through the RC layer and the conduction of heat over the steel layer are obtained in the second step. In concrete, the transfer of water vapour, dry air, and free water is discussed as well as the evaporation and liquefaction phenomena and the dehydration of concrete and its thermal and mechanical degradation. Within the framework of the third step, a geometrically and materially non-linear mechanical response of the structure is proposed accounting for interlayer slips and uplifts as well as for various material-related phenomena such as the material hardening/softening and creep. The governing equations are solved numerically. An efficient, novel strain-based finite element formulation is introduced for the mechanical analysis. Due to its generality and consideration of several different possible non-linear material, geometrical, and interlayer contact phenomena and their couplings the model can be of a use to a broader fire science community for exploring the impact of different physical parameters on the results of the addressed numerical simulations, thereby providing directions for further research. In the paper a case of such a study is also demonstrated exploring the contribution of the steel sheet and the flexibility of the interlayer connection of a standard trapezoidal steel–RC slab to its ultimate fire resistance. A reasonable contribution of the sheet is proved if the stiffness ratio between the integrated and the external tensile reinforcement of the RC plate is low provided that the contact connection is sufficiently stiff.
Ključne besede: Steel–RC composite structures
Fire
Slip
Uplift
Heat and moisture transfer
Contact stiffness
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1022. Engineering chimeric PCSK9 for a vaccine against atherosclerosisŠpela Malenšek, Duško Lainšček, Hana Esih, Sara Orehek, Tina Fink, Anja Golob Urbanc, Aleš Blinc, Roman Jerala, 2025, izvirni znanstveni članek Objavljeno v DiRROS: 26.09.2025; Ogledov: 300; Prenosov: 139
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1023. Characteristics of lightweight aggregate concrete interfacial transition zoneVesna Milovanović, Vilma Ducman, Miroslava Radeka, 2014, izvirni znanstveni članek Povzetek: The paper presents the characteristics of the interfacial zone between the lightweight aggregate produced on the basis of waste materials and binder matrix with the application of the methods SEM, EDS and the Vickers micro hardness test. On the basis of the SEM and EDS analysis, as well as the criteria for the atomic ratio of elements which compose some products of hydration, we can gain insight into the dominant composition of the interfacial zone. The values of the Vickers micro hardness test for four kinds of tested concrete after seven days of hydration is impossible to correlate with the composition of the interfacial zone in reliable way, whereas after twenty eight days the differences in values are insignificant.
Ključne besede: lightweight aggregate, waste material, interfacial zone
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1024. Corrosion properties of different forms of carbon steel in simulated concrete pore waterAleš Česen, Tadeja Kosec, Andraž Legat, Violeta Bokan-Bosiljkov, 2014, izvirni znanstveni članek Povzetek: Carbon steel, such as concrete-reinforcing steel, tends to undergo corrosion processes when exposed to certain environmental actions. These are the carbonation of concrete and the ingress of chlorides into the concrete from the environment. Many times, the carbonation and chloride contamination are simultaneous processes leading to a harsh corrosion environment and subsequent corrosion problems. Monitoring the state of corrosion is thereby a very useful and powerful tool for following and evaluating the lifetime of reinforced concrete structures. Electrochemical measurements were performed to investigate different forms of carbon steel in simulated concrete pore water at different pH values with and without the presence of chlorides. Morphological characteristics of three different types of carbon steel were studied and SEM/EDX and Raman analyses of the corrosion products were performed. It was found that steel in the form of a sheet has a higher corrosion resistivity than a steel wire and a steel rod, and that the steel rod has a higher corrosion resistivity than the steel wire. The corrosion layer on carbon steel is very diverse; several morphologies were found and analyzed.
Ključne besede: carbon steel, metallography, corrosion, concrete, water
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1025. Transcriptome insights reveal root hair inhibition and ROS imbalance in radish seedlings treated with rhizome extracts of invasive Fallopia speciesKatarina Šoln, Rebeka Strah, Anna Gasperl, Špela Baebler, Maruša Pompe Novak, Edith Stabentheiner, Maria Mueller, Jasna Dolenc Koce, 2025, izvirni znanstveni članek Ključne besede: allelopathy, Bohemian knotweed, Japanese knotweed, oxidative stress, root hair, transcriptomics
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1026. Using weigh-in-motion data to determine bridge dynamic amplification factorJan Kalin, Aleš Žnidarič, Maja Kreslin, 2015, objavljeni znanstveni prispevek na konferenci Povzetek: The dynamic component of bridge traffic loading is commonly taken into account with a Dynamic Amplification Factor (DAF) - the ratio between the maximum dynamic and static load effects on a bridge. In the design codes, this factor is generally higher than in reality. While this is fine for new bridges that must account for various risks during their life-time, it imposes unnecessary conservativism into assessment of the existing well defined bridges. Therefore, analysis of existing bridges should apply more realistic DAF values. One way of obtaining them experimentally is by bridge weigh-in-motion (B-WIM) measurements, which use an existing instrumented bridge or culvert to weigh all crossing vehicles at highway speeds. The B-WIM system had been equipped with two methods of obtaining an approximation to the static response of the. The first method uses the sum of influence lines. This method relies on accurate axle identification, the failure of which can have a large influence on the DAF value. The other method uses a pre-determined low-pass filter to remove the dynamic component of the measured signal; however an expert is needed to set the filter parameters. A new approach that tries to eliminate these two drawbacks has been developed. In this approach the parameters for the filter are determined automatically by fitting the filtered response to the sum of the influence lines. The measurement of DAF on a typical bridge site agrees with experiments performed in the ARCHES [1] project: dynamic amplification decreases as static loading increases.
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