Rezensionen

Bücher in der Diskussion - Thema Bildung: 1) Horlacher, Rebekka: Bildung. UTB Profile. Bern: Haupt 2011. ISBN 978-3-8252-3522-2. 2) Lenz, Werner: Wertvolle Bildung - kritisch … skeptisch … sozial. Wien: Löcker 2011. ISBN 978-85409-591-0. 3) Maaser, Michael; Walther, Gerrit: Bildung - Ziele und Formen, Traditionen und Systeme, Medien und Akteure. Stuttgart: J.B. Metzler‘sche Verlagsbuchhandlung 2011. ISBN 978-3-476-02098-7. 4) Roth, Gerhard: Bildung braucht Persönlichkeit - wie Lernen gelingt. Stuttgart: Klett-Cotta 2011, 3. Aufl. ISBN 978-3-608-94655-0. / Rezensionen zu: 5) Möller, Svenja: Marketing in der Erwachsenenbildung. Bielefeld: W. Bertelsmann 2011. ISBN 978-3-7639-4902-1. 6) Rikowski-Bertsch, Anke: Die grundtvigsche Volkshochschule als Idee und Institution und ihre Rezeption für die Erwachsenenbildung heute. Saarbrücken: VDM Verl. Dr. Müller 2010. ISBN 978-3-639-23580-7. 7) Horst Siebert: Lernen und Bildung Erwachsener. Erwachsenenbildung und lebensbegleitendes Lernen, Bd. 17. Bielefeld: W. Bertelsmann 2011. ISBN 978-3-7639-4848-2. 8) Egloff, Birte; Grotlüschen, Anke (Hrsg.): Forschen im Feld der Alphabetisierung und Grundbildung: ein Werkstattbuch. Münster: Waxmann 2011. ISBN 978-3-8309-2463-0. 9) Kathrin Berdelmann: Operieren mit der Zeit: Empirie und Theorie von Zeitstrukturen in Lehr-/Lernprozessen. Paderborn: Schöningh 2010. ISBN 978-3-506-77041-7. 10) Peter Faulstich: Aufklärung, Wissenschaft und lebensentfaltende Bildung. Geschichte und Gegenwart einer großen Hoffnung der Moderne. Bielefeld. Transcript-Verl. 2011. ISBN 978-3-8376-1816-7

Influence of Concrete Shrinkage on the Behavior of Carbon Short-Fiber-Reinforced Concrete (CSFRC) under Tension

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

Evaluation of the behavior of Carbon Short Fiber Reinforced Concrete (CSFRC) based on a multi-sensory experimental investigation and a numerical multiscale approach

Carbon fiber reinforcement used in concrete has become a remarkable alternative to steel fibers. Admixing short fibers to fresh concrete and processing the material with a 3D printer leads to an orientation of fibers and a material with high uniaxial strength properties, which offers an economic use of fibers. To investigate its mechanical behavior, the material is subjected to flexural and tensional tests, combining several measuring techniques. Numerical analysis complements this research. Computed tomography is used with several post-processing algorithms for separating matrix and fibers. This helps to validate fiber alignment and serves as input data for numerical analysis with representative volume elements concatenating real fiber position and orientation with the three-dimensional stress tensor. Flexural and uniaxial tensional tests are performed combining multiple measuring techniques. Next to conventional displacement and strain measuring methods, sound emission analysis, in terms of quantitative event analysis and amplitude appraisal, and also high-resolution digital image correlation accompany the tests. Due to the electrical conductibility of carbon fibers, the material’s resistivity could be measured during testing. All sensors detect the material’s degradation behavior comparably, showing a strain-hardening effect, which results from multiple, yet locally restricted and distributed, microcracks arising in combination with plastic deformation