Herrn Univ. Prof. Dr.-Ing. Gerhard Hanswille zur Vollendung seines 65. Lebensjahres gewidmet Grout-Verbindungen sind ein häufig eingesetztes Konstruktionsdetail in Offshore-Windenergieanlagen und ...-Plattformen. Sie stellen eine lastabtragende Verbindung zwischen gerammten Pfählen und Tragstruktur her. Bei aufgelösten Unterstrukturen befindet sich diese Verbindung ublicherweise unter Wasser. Ein möglicher Wassereinfluss auf das Ermudungsverhalten des Konstruktionsdetails wurde in fruheren Versuchen und den daraus abgeleiteten Bemessungsverfahren nicht berucksichtigt. Die in dieser Veröffentlichung beschriebenen versuchsgestutzten Untersuchungen zeigen an klein- und großskaligen Versuchskörpern eine deutliche Reduktion der Lebensdauer bei Ermudungsbeanspruchung unter Wasser gegenuber trockenen Umgebungsbedingungen. Neben einer Beeinflussung der Lebensdauer verändert das umgebende Wasser auftretende Schadensmechanismen in der Verbindung. On the fatigue behaviour of grouted connections at varied ambient conditions. Grouted connections are a frequently used structural detail of offshore wind turbines and platforms for the load transferring connection between piles and support structure. At latticed substructures this connection is commonly located at mudline. However, a potential influence of the surrounding water on the connection's fatigue behaviour was neglected in earlier tests and consequential design methods. Herein described experimental investigations at small and large-scale fatigue tests in submerged conditions, showed a significant reduction of endurable load cycles. In addition, the water impact caused varied damage mechanism in the connection.
Resumo O artigo tem como objeto analisar a hiperconexão causada pelo teletrabalho dos professores como hipótese de dano existencial. O trabalho docente presencial no período da pandemia causada pelo ...novo coronavírus foi substituído pelo ensino remoto emergencial (ERE) para inibir o contágio e, assim, contribuir para conter a crise sanitária de abrangência mundial e garantir o direito à educação de crianças, jovens e adultos. Dessa forma os professores tiveram, abruptamente, de se adaptar ao trabalho por meio de plataformas virtuais e aplicativos multiplataforma para smartphones. Essa mudança, somada ao contexto de aflição causado pela pandemia, pode ocasionar um dano existencial no docente devido à violação do direito à desconexão. Sob essa perspectiva, a pesquisa parte do problema: seria esse um dano de natureza individual ou coletiva? Assim, trazemos como hipótese: a mudança abrupta do ensino presencial para o remoto da forma como ocorreu configura dano existencial à categoria. Para tal propósito, esta investigação tem por objetivo geral: refletir, com base na mudança abrupta do ensino presencial para o remoto, de que forma a hiperconexão causada pelo trabalho virtual configura dano existencial aos professores. Para o desenvolvimento deste estudo teórico e de cunho exploratório, utiliza-se uma abordagem qualitativa, aliada a um procedimento de pesquisa bibliográfica. Enquanto referencial teórico, tomamos como base o conceito de sociedade do desempenho de Byung-Chul Han. A partir dos elementos que caracterizam o dano existencial, podemos inferir que o trabalho remoto dos docentes, em tais condições, pode concorrer para violação ao direito à desconexão e ao consequente dano existencial.
Abstract The article aims to analyze the hyperconnection caused by teachers’ telework as a hypothesis of existential damage. Face-to-face teaching during the pandemic caused by the novel coronavirus has been replaced by emergency remote teaching (ERE) to inhibit contagion and thus contribute to containing the global health crisis and ensuring the right to education of children, young people and adults. In this way, teachers had to abruptly adapt to their work through virtual platforms and multiplatform applications for smartphones. This change, in the context of distress caused by the pandemic, can cause existential damage to the teacher due to the violation of the right to disconnection. From this perspective, the research aims to answer the following question: is this a demage of an individual or collective nature? Thus, we bring as a hypothesis: the abrupt change from face-to-face to remote teaching in the way it occurred configures existential damage to the category. For this purpose, this investigation has as general objective: to reflect, based on the abrupt change from face-to-face to remote teaching, how the hyperconnection caused by virtual work configures existential damage to teachers. For the development of this theoretical and exploratory study, a qualitative approach is used, combined with a bibliographic research procedure. As a theoretical framework, we take as a basis Byung-Chul Han’s concept of the performance society. From the elements that characterize the existential damage, we can infer that the remote work of teachers, in such conditions, can contribute to the violation of the right to disconnection and the consequent existential damage.
U radu je istražen utjecaj temperature i mjesta zajeda uzorka na udarnu žilavost materijala tračničke osovine u eksploataciji. Dobiveni rezultati pokazuju obrnutu proporcionalnost ovisnosti udarne ...žilavosti o polumjeru zajeda na uzorcima. Smanjenjem temperature ispitivanja od +20 to –40 °C značajno se smanjuje udarna žilavost i udio žilavog loma.
Study on the Fatigue Behaviour of Toothed Belts AMIJIMA, Sadao; FUJII, Toru; KITABAYASHI, Masayuki
Transactions of the Japan Society of Mechanical Engineers Series C,
1989/06/25, Letnik:
55, Številka:
514
Journal Article
Odprti dostop
Fatigue characteristics of toothed belts under constant power transmission were experimentally investigated. Surface temperature of the belt and initial tension during fatigue tests were measured. ...Dynamic spring constant and hysteresis loss were also measured at the several stages of the fatigue using visco-elastic testing machine. It is easily predicted that the load distribution along the pulley changes as the fatigue of the belt progresses due to the stiffness change of the belt. Therefore, we also measured the load distribution intermittently during fatigue. It was found that the S-N curves of the toothed belt is represented by two lines. At low cycles, the jumping fatigue is the main failure mode and the first line of S-N curve shows this domain. The slope of the second line is smaller than that of the first line. Fatigue process is divided into three stage according to the temperature of the belt surface. At the first stage (from 0 to 10% fatigue life ratio ; flr), the temperature rapidly rises. During the second stage, the temperature rise is little. The third stage starts at 90% flr., and the temperature again goes up rapidly. Then, final fatigue failure occurs. The initial tension change resembles the temperature change.
Well, Serbia. Damaged buildings of a city. In the background river with flood plains.
DFG project: worldviews (2015-2017), record author: Deutsche Fotothek/SLUB Dresden (DF)
Wohl Serbien. Durch ...Beschuss beschädigte Gebäude einer Stadt. Im Hintergrund Fluss mit Überschwemmungsflächen.
Negativ aus Glas in schwarzweiß, quer
DFG-Projekt: Weltsichten (2015-2017), Datensatz-Urheber: Deutsche Fotothek / SLUB Dresden (Förderung)
PDF
