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Engineers and therefore engineering education are challenged by the increasing complexity of questions to be answered globally. The education of future engineers therefore has to answer with curriculums that build up relevant skills. This chapter will give an example how to bring engineering and social responsibility successful together to build engineers of tomorrow. Through the integration of gender and diversity perspectives, engineering research and teaching is expanded with new perspectives and contents providing an important potential for innovation. Aiming on the enhancement of engineering education with distinctive competencies beyond technical expertise, the teaching approach introduced in the chapter represents key factors to ensure that coming generations of engineers will be able to meet the requirements and challenges a changing globalized world holds for them. The chapter will describe how this approach successfully has been implemented in the curriculum in engineering of a leading technical university in Germany.
Evaluation of fragility curves for a three-storey-reinforced-concrete mock-up of SMART 2013 project
(2016)
Engineers are of particular importance for the societies of tomorrow. The big social challenges society has to cope with in future, can only be mastered, if engineers link the development and innovation process closely with the requirements of people. As a result, in the frame of the innovation process engineers have to design and develop products for diverse users. Therefore, the consideration of diversity in this process is a core competence engineers should have. Implementing the consideration of diverse requirements into product design is also linked to the development of sustainable products and thus leads to social responsible research and development, the core concept formulated by the EU.
For this reason, future engineers should be educated to look at the technical perspectives of a problem embedded in the related questions within societies they are developing their artefacts for. As a result, the aim of teaching engineering should be to prepare engineers for these requirements and to draw attention to the diverse needs in a globalized world.
To match the competence profiles of future engineers to the global challenges and the resulting social responsibility, RWTH Aachen University, one of the leading technical universities in Germany, has established the bridging professorship “Gender and Diversity in Engineering” (GDI) which educates engineers with an interdisciplinary approach to expand engineering limits. The interdisciplinary teaching concept of the research group pursues an approach which imparts an application oriented Gender and Diversity expertise to future engineers. In the frame of an established teaching concept, which is a result of experiences and expertise of the research group, students gain theoretical knowledge about Gender and Diversity and learn how to transfer their knowledge into their later field of action.
In the frame of the conference the institutional approach will be presented as well as the teaching concept which will be introduced by concrete course examples.
The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha⁻¹, whereas the highest dry matter of 70% to 80% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha⁻¹; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500 °C, associated with a net calorific value of 16.5–17.2 MJ kg⁻¹. All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications.
In Anbetracht weltweit zunehmend strengerer klimapolitischer
Ziele steigt auch der Druck für Nutzfahrzeughersteller, effizientere und umweltfreundlichere
Technologien zu entwickeln. Den Blick bei der Bewertung dieser
ausschließlich auf die Fahrzeugnutzung zu richten, ist längst nicht mehr zufriedenstellend.
Im Rahmen dieser Analyse wird ein gegenwärtig auf dem Markt erwerblicher
und in deutschen Städten bereits seit Jahren betriebener Hybridbus
energetisch und ökologisch mit einem konventionell angetriebenen, nahezu baugleichen
Modell entlang des Lebensweges bewertet.
Nach Definition von Ziel und Untersuchungsrahmen wird ein Überblick auf bereits
durchgeführte Lebenszyklusanalysen zu Hybridbussen im Stadtverkehr gegeben
und Schlussfolgerungen für die anschließende Analyse abgeleitet. Diese
wird im Rahmen einer energetischen und ökologischen Bewertung beider Produktsysteme
anhand der Parameter "Primärenergieeinsatz" und "CO2äq Emissionen"
praktiziert. Der Fahrzeugrumpf beider Fahrzeuge des gleichen Modells
wird dabei als einheitlich angenommen, sodass bei dem Vergleich der Herstellung
vereinfacht nur die sich unterscheidenden Komponenten des Antriebstranges
berücksichtigt werden. Die Resultate der Wirkungsabschätzung werden als
Differenz des Hybridbusses gegenüber dem Referenzfahrzeug über die einzelnen
Lebenszyklusphasen dargestellt. Schließlich werden Prognosen getroffen, ab
welcher Strecke die bei der Herstellung erzeugten höheren CO2äq Emissionen
des Hybridantriebstranges gegenüber dem Referenzmodell ausgeglichen werden.
Für das Auftreten extremer Wetterereignisse werden für Kernkraftwerke Eintrittshäufigkeiten für nicht mehr beherrschbare Zustände von unter 10⁻⁴/a gefordert. Dies gilt auch für die Einwirkung von Blitzeinschlägen. Die bisherige Nachweisführung zu Blitz- und Überspannungsschutz eines KKW in Deutschland ist deterministisch. In diesem Bericht werden das Vorgehen für einen entsprechenden Nachweis für leittechnische Einrichtungen der Sicherheitstechnik von KKW, der zur geforderten Zielgröße der Eintrittshäufigkeit führt. Die Ergebnisse werden zusammenfassend bewertet.
A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank-liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross-interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell-liquid-soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock.
The behaviour of infilled reinforced concrete frames under horizontal load has been widely investigated, both experimentally and numerically. Since experimental tests represent large investments, numerical simulations offer an efficient approach for a more comprehensive analysis. When RC frames with masonry infill walls are subjected to horizontal loading, their behaviour is highly non-linear after a certain limit, which makes their analysis quite difficult. The non-linear behaviour results from the complex inelastic material properties of the concrete, infill wall and conditions at the wall-frame interface. In order to investigate this non-linear behaviour in detail, a finite element model using a micro modelling approach is developed, which is able to predict the complex non-linear behaviour resulting from the different materials and their interaction. Concrete and bricks are represented by a non-linear material model, while each reinforcement bar is represented as an individual part installed in the concrete part and behaving elasto-plastically. Each brick is modelled individually and connected taking into account the non-linearity of a brick mortar interface. The same approach is followed using two finite element software packages and the results are compared with the experimental results. The numerical models show a good agreement with the experiments in predicting the overall behaviour, but also very good matching for strength capacity and drift. The results emphasize the quality and the valuable contribution of the numerical models for use in parametric studies, which are needed for the derivation of design recommendations for infilled frame structures.
Eine seismische Anregung verursacht in einem Flüssigkeitstank einen kombinierten Spannungszustand, was zu einem Stabilitätsversagen der häufig sehr dünnwandigen Konstruktionen führen kann. Für die Durchführung von Stabilitätsnachweisen stehen verschiedene Verfahren zur Verfügung. Üblicherweise werden aus Gründen der Einfachheit spannungsbasierte Verfahren angewendet. Diese sind für Einheitslastfälle experimentell abgesichert, wobei eine Übertragung auf kombinierte Spannungszustände wie im Erdbebenfall nur begrenzt möglich ist. Alternativ kann ein globales, numerisches Konzept, das LBA/MNA-Verfahren, angewendet werden. Das Verfahren kombiniert eine materiell nichtlineare Berechnung (MNA) mit einer linearen Beulanalyse (LBA) und erfasst die Interaktion verschiedener gleichzeitig auftretender Beanspruchungen implizit im Nachweis. Dieser Beitrag demonstriert die Anwendung der Verfahren am Beispiel verschiedener Tankgeometrien mit Höhe/Radius-Verhältnissen zwischen 1 ≤ H/R ≤ 2 und Radius/Tankwand-Verhältnissen zwischen 500 ≤ R/t ≤ 1000 und diskutiert zusätzlich die Defizite der spannungsbasierten Nachweisverfahren.
This paper describes the procedure on the evaluation of the masonry chapter for the next generation of Eurocode 8, the European Standard for earthquake-resistant design. In CEN, TC 250/SC8, working group WG 1 has been established to support the subcommittee on the topic of masonry on both design of new structures (EN1998-1) and assessment of existing structures (EN1998-3). The aim is to elaborate suggestions for amendments which fit the current state of the art in masonry and earthquake-resistant design. Focus will be on modelling, simplified methods, linear-analysis (q-values, overstrength-values), nonlinear procedures, out-of-plane design as well as on clearer definition of limit states. Beside these, topics related to general material properties, reinforced masonry, confined masonry, mixed structures and non-structural infills will be covered too. This paper presents the preliminary work and results up to the submission date.