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Simulation of concrete ageing on dams as illustrated by numerical analysis of Jablanica HPPThe paper presents a model for numerical simulation of interaction between the fluid and the reinforced-concrete structure under seismic load for spatial 3D problems, with an emphasis of concrete dams. The model is based on the so called partition scheme for coupled (multi-field) problems. The model especially focuses on the concrete ageing effects, which has proven to be highly significant in the analysis of older structures. The paper starts with a brief description of the numerical model, which is followed by a more detailed description of the concrete ageing model, and by analysis of Jablanica hydropower plant (HPP) on which the validity of the model and related software was checked. Simulacija starenja betona brana na primjeru numeričke analize brane HE JablanicaRad prikazuje model za numeričku simulaciju međudjelovanja tekućine i armiranobetonske konstrukcije pod seizmičkim opterećenjem za prostorne 3D probleme, posebice betonske brane. Model je zasnovan na tzv. shemi odvojenih rješenja za probleme vezanih (višepoljnih) zadaća. Model posebice uključuje efekte starenja betona što se pokazalo vrlo bitnim kod analize starijih građevina. Prvo je vrlo kratko dan opis numeričkog modela, a zatim je detaljnije opisan model starenja betona i analiza brane HE Jablanica na kojoj je testirana valjanost modela i razvijenog softvera. Ključne riječi: betonska gravitacijska brana, numerički model, međudjelovanje tekućina-konstrukcija, proračun na potres, starenje betona Übersichtsarbeit Goran Šunjić, Maja Prskalo, Zoran Milašinović, Alen Harapin Simulation der Alterung von Betonstaudämmen am Beispiel der numerischen Analyse des Staudamms des Wasserkraftwerks Jablanica Die Arbeit zeigt ein Modell zur numerischen Simulation der Wechselwirkung von flüssigen und bewehrten Betonstrukturen unter seismischer Belastung für räumliche 3D-Probleme, insbesondere für Betonstaudämme. Das Modell basiert auf dem sog. Schema separater Lösungen für Probleme im Zusammenhang mit (mehrfeldigen) Aufgaben. Das Modell berücksichtigt insbesondere die Auswirkungen der Alterung von Beton, die sich bei der Analyse älterer Gebäude als sehr wichtig erwiesen hat. Zunächst werden eine sehr kurze Beschreibung des numerischen Modells gegeben, gefolgt von einer detaillierteren Beschreibung des Alterungsmodells des Betons und der Analyse des Staudamms des Wasserkraftwerks Jablanica, bei der die Gültigkeit des Modells und der entwickelten Software getestet wurde. Schlüsselwörter: Schwerkraftdamm aus Beton, numerisches Modell, Wechselwirkung Flüssigkeit-Struktur, Erdbebenberechnung, Betonalterung

Carbon short-fiber-reinforced concrete (CSFRC) is a novel material obtained by adding and mixing carbon fibers into fresh concrete. In this way, the concrete behavior is changed, and concrete no longer undergoes brittle failure under tension. Specifically, when concrete is reinforced with short carbon fibers, its tensile characteristics become similar to those of steel. For example, CSFRC exhibits a distinct ductility, enabling the concrete to withstand substantial damage before failure. This results in a higher energy dissipation capacity, which consequently also increases the tensile strength of the concrete. Accordingly, the tensile strength of CSFRC is about 400% higher than that of plain concrete and almost double that of UHPC. Because of the differences in mechanical performance compared to conventional concrete, extensive experimental and theoretical research is needed to characterize the behavior of CFRSC. Our main aim in this research is to investigate and describe the load bearing and deformation behavior of CSFRC, as well as the related damage processes.

Bridges as structures, but also as a symbol, draw the best out of a human, because by connecting two sides, they certainly always connect rather than separate, unite without dividing. The tasks of builders of primal bridges were limited to pedestrian crossings. Those were the first natural or constructed crossings made of fallen trees that were used for the needs of the then users. Today, pedestrian bridges are gaining importance by being constructed not only for communication but also as a modern way of healthy living. Construction of any structure, including a pedestrian bridge, requires its control. All bridges, regardless of their length, width and purpose, have in common that they must be tested. The Regulation on load testing of bridges (JUS U.M1.046) is one of the parts of legislation that must be adhered to. This Regulation defines the test procedures and evaluation of the results of tests on structures. In addition to a brief insight into modern pedestrian bridges, this paper presents practical examples of load testing of pedestrian bridges conducted by the staff of the Faculty of Civil Engineering, University of Mostar.