51. Measurements of bridge dynamic amplification factor using bridge weigh-in-motion dataJan Kalin, Aleš Žnidarič, Andrej Anžlin, Maja Kreslin, 2022, izvirni znanstveni članek Povzetek: The dynamic component of bridge traffic loading is commonly taken into account with a Dynamic Amplification Factor (DAF)—the ratio between the dynamic and static load effects on a bridge. In the design codes, this factor is generally more conservative than in reality. Recently a new method of cal- culation of this factor had been developed. Data from 15 different bridges have been analysed since then and this paper presents the results of the analyses. The background for Bridge Weigh-in-Motion is given, and the most recent method for DAF calculation is described. The sites from which the data originated are presented, and the selection of data discussed. The results of the analyses are presented and discussed and some examples of DAF calculations are shown. Data from the considered sites have invariably demonstrated a DAF decrease with increasing axle load. This is a significant result, especially for assessment of existing structures, since it is beneficial to use measured structural param- eters to optimise structural analysis.
Ključne besede: bridge loads, bridge weigh-in-motion, dynamic amplication factor, dynamic analysis, measurement, traffic loading
Objavljeno v DiRROS: 14.07.2023; Ogledov: 339; Prenosov: 177
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52. Model updating concept using bridge Weigh-in-Motion dataDoron Hekič, Andrej Anžlin, Maja Kreslin, Aleš Žnidarič, Peter Češarek, 2023, izvirni znanstveni članek Povzetek: Finite element (FE) model updating of bridges is based on the measured modal parameters and less frequently on the measured structural response under a known load. Until recently, the FE model updating did not consider strain measurements from sensors installed for weighing vehicles with bridge weigh-in-motion (B-WIM) systems. A 50-year-old multi-span concrete highway viaduct, renovated between 2017 and 2019, was equipped with continuous monitoring system with over 200 sensors, and a B-WIM system. In the most heavily instrumented span, the maximum measured longitudinal strains induced by the full-speed calibration vehicle passages were compared with the modelled strains. Based on the sensitivity study results, three variables that affected its overall stiffness were updated: Young’s modulus adjustment factor of all structural elements, and two anchorage reduction factors that considered the interaction between the superstructure and non-structural elements. The analysis confirmed the importance of the initial manual FE model updating to correctly reflect the non-structural elements during the automatic nonlinear optimisation. It also demonstrated a successful use of pseudo-static B-WIM loading data during the model updating process and the potential to extend the proposed approach to using random B-WIM-weighed vehicles for FE model updating and long-term monitoring of structural parameters and load-dependent phenomena.
Ključne besede: monitoring, bridge, viaduct, bridge weigh-in-motion (B-WIM), structural health monitoring (SHM), finite element (FE), calibration, model updating
Objavljeno v DiRROS: 29.05.2023; Ogledov: 449; Prenosov: 233
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53. Development and testing of a railway bridge weigh-in-motion systemDonya Hajializadeh, Aleš Žnidarič, Jan Kalin, Eugene J. OBrien, 2020, izvirni znanstveni članek Povzetek: This study describes the development and testing of a railway bridge weigh-in-motion (RB-WIM) system. The traditional bridge WIM (B-WIM) system developed for road bridges was extended here to calculate the weights of railway carriages. The system was tested using the measured response from a test bridge in Poland, and the accuracy of the system was assessed using statically-weighed trains. To accommodate variable velocity of the trains, the standard B-WIM algorithm, which assumes a constant velocity during the passage of a vehicle, was adjusted and the algorithm revised accordingly. The results showed that the vast majority of the calculated carriage weights fell within %5% of their true, statically-weighed values. The sensitivity of the method to the calibration methods was then assessed using regression models, trained by di%erent combinations of calibration trains.
Ključne besede: bridge weigh-in-motion, railway bridge loading, bridge instrumentation, B-WIM
Objavljeno v DiRROS: 22.05.2023; Ogledov: 351; Prenosov: 165
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54. Kako ravnati, ko civilna družba nasprotuje gozdarskim ukrepom?Boris Rantaša, Aleš Poljanec, 2023, predgovor, uvodnik, spremna beseda Ključne besede: javno mnenje, gozdarski ukrepi, Krajinski park Tivoli, Rožnik in Šišenski hrib, Tivoli, Rožnik, Šišenski hrib, Ljubljana
Objavljeno v DiRROS: 19.05.2023; Ogledov: 362; Prenosov: 97
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56. Upravljanje prostoživečih živali čezmejnega območja Julijskih Alp na primeru alpskega kozoroga in severnega (alpskega) gamsaAndreja Nève Repe, Andrej Arih, Marco Favalli, Irena Bertoncelj, Aleš Poljanec, 2023, strokovni članek Povzetek: Ekološka povezljivost je osnova, ki omogoča naravne procese vrst, kot so pretok genov, selitev, širjenje arealov vrst, in je pomembna za dolgoročno ohranjanje vrst ter njihovih habitatov. Za zagotavljanje ekološke povezljivosti je bistvena fizična povezanost habitatov in enostavno prehajanje osebkov ter vrst med njimi. Ovira za prehajanje organizmov in ohranjanje vrst med državami so razlike v politikah, zakonodaji in upravljanju prostoživečih živali. Neusklajeno upravljanje s prostoživečimi živalmi na obeh straneh državne meje lahko povzroči težave pri povezovanju populacij nekaterih vrst, ker vpliva na gibanje in vedenje živali. Zato so čezmejna zavarovana območja pomembna za zagotavljanje ekološke povezljivosti med dvema državama ali več. Za alpski prostor sta pomembni vrsti alpski kozorog (Capra ibex) in severni (alpski) gams (Rupicapra rupicapra). Zato smo za čezmejno območje Julijskih Alp (velikost 289.660 ha), ki leži med Italijo in Slovenijo, v projektih AlpBioNet2030 in DINALPCONNECT analizirali stanje in upravljanje obeh vrst ter predlagali izboljšave upravljanja s ciljem izboljšati stanje populacij in zagotoviti ekološko povezljivost habitata za vrste na širšem čezmejnem območju. Od leta 2017 smo izpeljali štiri čezmejne delavnice z deležniki z italijanske in slovenske strani (predstavniki lovcev, lastnikov zemljišč, upravljavcev zavarovanih območij, gozdarjev, odločevalcev na nacionalni in regionalni ravni (ministrstva, občine) ter varstva narave). Rezultat participativnega procesa je čezmejni koncept celostnega upravljanja z alpskim kozorogom in severnim (alpskim) gamsom ter njunima habitatoma, ki vsebuje vizijo in strategijo čezmejnega upravljanja ter akcijski načrt na čezmejnem območju Julijskih Alp.
Ključne besede: ekološka povezljivost, alpski kozorog, severni (alpski) gams, čezmejno upravljanje, Julijske Alpe
Objavljeno v DiRROS: 19.04.2023; Ogledov: 570; Prenosov: 110
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59. Priporočila za obravnavo bolnikov z malignimi limfomiBarbara Jezeršek Novaković, Lučka Boltežar, Andreja Eberl, Gorana Gašljević, Biljana Grčar-Kuzmanov, Monika Jagodic, Tanja Južnič Šetina, Veronika Kloboves-Prevodnik, Gregor Kos, Aleš Christian Mihelač, Milica Miljković, Urška Rugelj, Marija Skoblar Vidmar, Uroš Smrdel, Danijela Štrbac, Miha Toplak, Lorna Zadravec-Zaletel, 2023, strokovna monografija Ključne besede: maligni limfomi, smernice, novotvorbe
Objavljeno v DiRROS: 24.01.2023; Ogledov: 755; Prenosov: 299
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