TY - JOUR A1 - Mykoniou, Konstantin A1 - Butenweg, Christoph A1 - Holtschoppen, Britta A1 - Klinkel, Sven T1 - Seismic response analysis of adjacent liquid-storage tanks JF - Earthquake engineering and structural dynamics N2 - 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. KW - liquid-structure interaction KW - seismic response KW - impulsive effects KW - liquid-storage tank KW - structure-soil-structure interaction Y1 - 2016 U6 - http://dx.doi.org/10.1002/eqe.2726 SN - 1096-9845 (E-Journal); 0098-8847 (Print) VL - 45 IS - 11 SP - 1779 EP - 1796 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Jablonowski, Nicolai David A1 - Kollmann, Tobias A1 - Nabel, Moritz A1 - Damm, Tatjana A1 - Klose, Holger A1 - Müller, Michael A1 - Bläsing, Marc A1 - Seebold, Sören A1 - Krafft, Simone A1 - Kuperjans, Isabel A1 - Dahmen, Markus A1 - Schurr, Ulrich T1 - Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes JF - GCB [Global Change Biology] Bioenergy N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.1111/gcbb.12346 SN - 1757-1707 (online) SN - 1757-1693 (print) N1 - Special Issue: Perennial biomass crops for a resource constrained world VL - 9 IS - 1 SP - 202 EP - 214 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Kern, Alexander T1 - Blitz- und Überspannungsschutz von Kernkraftwerken - Nachweisführung der ausreichenden Sicherheit für leittechnische Einrichtungen auch bei Blitzeinschlägen mit extremen Parametern JF - Atw. International Journal for Nuclear Power N2 - 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. Y1 - 2016 SN - 1431-5254 VL - 61 IS - 8/9 SP - 534 EP - 543 PB - Inforum CY - Berlin ER - TY - JOUR A1 - Rosin, Julia A1 - Butenweg, Christoph A1 - Klinkel, Sven T1 - Stabilitätsnachweis für seismisch beanspruchte Tankbauwerke nach dem LBA/MNA-Konzept JF - Bauingenieur N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.37544/0005-6650-2016-12-74 SN - 0005-6650 VL - 91 IS - 12 SP - 518 EP - 526 PB - VDI Fachmedien CY - Düsseldorf ER - TY - JOUR A1 - Butenweg, Christoph A1 - Marinkovic, Marko A1 - Kubalski, Thomas A1 - Klinkel, Sven T1 - Masonry infilled reinforced concrete frames under horizontal loading T1 - Stahlbetonrahmen mit Ausfachungen aus Mauerwerk unter horizontalen Belastungen JF - Mauerwerk N2 - 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. Y1 - 2016 U6 - http://dx.doi.org/10.1002/dama.201600703 SN - 1437-1022 VL - 20 IS - 4 SP - 305 EP - 312 PB - Ernst & Sohn CY - Berlin ER -