@inproceedings{ButenwegRajan2014, author = {Butenweg, Christoph and Rajan, Sreelakshmy}, title = {Design and construction techniques of AAC masonry buildings in earthquakes regions}, series = {10 years Xella research in Building Materials : Symposium on the 4th and 5th of September, Potsdam 2014}, booktitle = {10 years Xella research in Building Materials : Symposium on the 4th and 5th of September, Potsdam 2014}, year = {2014}, language = {en} } @inproceedings{ButenwegMeyerFehling2014, author = {Butenweg, Christoph and Meyer, Udo and Fehling, Ekkehard}, title = {INSYSME: first activities of the German partners}, series = {9th International Masonry Conference 2014 in Guimaraes, Portugal, 2014}, booktitle = {9th International Masonry Conference 2014 in Guimaraes, Portugal, 2014}, year = {2014}, language = {en} } @inproceedings{WalterElsenMuelleretal.1999, author = {Walter, Peter and Elsen, Ingo and M{\"u}ller, Holger and Kraiss, Karl-Friedrich}, title = {3D object recognition with a specialized mixtures of experts architecture}, series = {IJCNN'99. International Joint Conference on Neural Networks. Proceedings}, booktitle = {IJCNN'99. International Joint Conference on Neural Networks. Proceedings}, publisher = {IEEE}, address = {New York}, isbn = {0-7803-5529-6}, issn = {1098-7576}, doi = {10.1109/IJCNN.1999.836243}, pages = {3563 -- 3568}, year = {1999}, abstract = {Aim of the AXON2 project (Adaptive Expert System for Object Recogniton using Neuml Networks) is the development of an object recognition system (ORS) capable of recognizing isolated 3d objects from arbitrary views. Commonly, classification is based on a single feature extracted from the original image. Here we present an architecture adapted from the Mixtures of Eaqerts algorithm which uses multiple neuml networks to integmte different features. During tmining each neural network specializes in a subset of objects or object views appropriate to the properties of the corresponding feature space. In recognition mode the system dynamically chooses the most relevant features and combines them with maximum eficiency. The remaining less relevant features arz not computed and do therefore not decelerate the-recognition process. Thus, the algorithm is well suited for ml-time applications.}, language = {en} } @inproceedings{Elsen1998, author = {Elsen, Ingo}, title = {A pixel based approach to view based object recognition with self-organizing neural networks}, series = {IECON'98. Proceedings of the 24th Annual Conference of the IEEE Industrial Electronics Society}, booktitle = {IECON'98. Proceedings of the 24th Annual Conference of the IEEE Industrial Electronics Society}, publisher = {IEEE}, address = {New York}, isbn = {0-7803-4503-7}, doi = {10.1109/IECON.1998.724032}, pages = {2040 -- 2044}, year = {1998}, abstract = {This paper addresses the pixel based classification of three dimensional objects from arbitrary views. To perform this task a coding strategy, inspired by the biological model of human vision, for pixel data is described. The coding strategy ensures that the input data is invariant against shift, scale and rotation of the object in the input domain. The image data is used as input to a class of self organizing neural networks, the Kohonen-maps or self-organizing feature maps (SOFM). To verify this approach two test sets have been generated: the first set, consisting of artificially generated images, is used to examine the classification properties of the SOFMs; the second test set examines the clustering capabilities of the SOFM when real world image data is applied to the network after it has been preprocessed to be invariant against shift, scale and rotation. It is shown that the clustering capability of the SOFM is strongly dependant on the invariance coding of the images.}, language = {en} } @inproceedings{ElsenKraissKrumbiegel1997, author = {Elsen, Ingo and Kraiss, Karl-Friedrich and Krumbiegel, Dirk}, title = {Pixel based 3D object recognition with bidirectional associative memories}, series = {International Conference on Neural Networks 1997}, booktitle = {International Conference on Neural Networks 1997}, publisher = {IEEE}, address = {New York}, isbn = {0-7803-4122-8}, pages = {1679 -- 1684}, year = {1997}, abstract = {This paper addresses the pixel based recognition of 3D objects with bidirectional associative memories. Computational power and memory requirements for this approach are identified and compared to the performance of current computer architectures by benchmarking different processors. It is shown, that the performance of special purpose hardware, like neurocomputers, is between one and two orders of magnitude higher than the performance of mainstream hardware. On the other hand, the calculation of small neural networks is performed more efficiently on mainstream processors. Based on these results a novel concept is developed, which is tailored for the efficient calculation of bidirectional associative memories. The computational efficiency is further enhanced by the application of algorithms and storage techniques which are matched to characteristics of the application at hand.}, language = {en} } @inproceedings{MilijašŠakićMarinkovićetal.2021, author = {Milijaš, Aleksa and Šakić, Bogdan and Marinković, Marko and Butenweg, Christoph}, title = {Experimental investigation of behaviour of masonry infilled RC frames under out-of-plane loading}, series = {Proceedings of COMPDYN 2021}, booktitle = {Proceedings of COMPDYN 2021}, editor = {Papadrakakis, Manolis and Fragiadakis, Michalis}, publisher = {National Technical University of Athens}, address = {Athen}, isbn = {978-618-85072-5-8}, issn = {2623-3347}, doi = {10.7712/120121.8528.18914}, pages = {829 -- 846}, year = {2021}, abstract = {Masonry infills are commonly used as exterior or interior walls in reinforced concrete (RC) frame structures and they can be encountered all over the world, including earthquake prone regions. Since the middle of the 20th century the behaviour of these non-structural elements under seismic loading has been studied in numerous experimental campaigns. However, most of the studies were carried out by means of in-plane tests, while there is a lack of out-of-plane experimental investigations. In this paper, the out-of-plane tests carried out on full scale masonry infilled frames are described. The results of the out-of-plane tests are presented in terms of force-displacement curves and measured out-of-plane displacements. Finally, the reliability of existing analytical approaches developed to estimate the out-of-plane strength of masonry infills is examined on presented experimental results.}, language = {en} } @inproceedings{ŠakićMilijašMarinkovićetal.2021, author = {Šakić, Bogdan and Milijaš, Aleksa and Marinković, Marko and Butenweg, Christoph and Klinkel, Sven}, title = {Influence of prior in-plane damage on the out-of-plane response of non-load bearing unreinforced masonry walls under seismic load}, series = {Proceedings of COMPDYN 2021}, booktitle = {Proceedings of COMPDYN 2021}, editor = {Papadrakakis, Manolis and Fragiadakis, Michalis}, publisher = {National Technical University of Athens}, address = {Athen}, isbn = {9786188507258}, issn = {2623-3347}, doi = {10.7712/120121.8527.18913}, pages = {808 -- 828}, year = {2021}, abstract = {Reinforced concrete frames with masonry infill walls are popular form of construction all over the world as well in seismic regions. While severe earthquakes can cause high level of damage of both reinforced concrete and masonry infills, earthquakes of lower to medium intensity some-times can cause significant level of damage of masonry infill walls. Especially important is the level of damage of face loaded infill masonry walls (out-of-plane direction) as out-of-plane load cannot only bring high level of damage to the wall, it can also be life-threating for the people near the wall. The response in out-of-plane direction directly depends on the prior in-plane damage, as previous investigation shown that it decreases resistance capacity of the in-fills. Behaviour of infill masonry walls with and without prior in-plane load is investigated in the experimental campaign and the results are presented in this paper. These results are later compared with analytical approaches for the out-of-plane resistance from the literature. Conclusions based on the experimental campaign on the influence of prior in-plane damage on the out-of-plane response of infill walls are compared with the conclusions from other authors who investigated the same problematic.}, language = {en} } @inproceedings{TomicPennaDeJongetal.2020, author = {Tomic, Igor and Penna, Andrea and DeJong, Matthew and Butenweg, Christoph and Senaldi, Ilaria and Guerrini, Gabriele and Malomo, Daniele and Beyer, Katrin}, title = {Blind predictions of shake table testing of aggregate masonry buildings}, series = {Proceedings of the 17th World Conference on Earthquake Engineering}, booktitle = {Proceedings of the 17th World Conference on Earthquake Engineering}, year = {2020}, abstract = {In many historical centers in Europe, stone masonry is part of building aggregates, which developed when the layout of the city or village was densified. The analysis of such building aggregates is very challenging and modelling guidelines missing. Advances in the development of analysis methods have been impeded by the lack of experimental data on the seismic response of such aggregates. The SERA project AIMS (Seismic Testing of Adjacent Interacting Masonry Structures) provides such experimental data by testing an aggregate of two buildings under two horizontal components of dynamic excitation. With the aim to advance the modelling of unreinforced masonry aggregates, a blind prediction competition is organized before the experimental campaign. Each group has been provided a complete set of construction drawings, material properties, testing sequence and the list of measurements to be reported. The applied modelling approaches span from equivalent frame models to Finite Element models using shell elements and discrete element models with solid elements. This paper compares the first entries, regarding the modelling approaches, results in terms of base shear, roof displacements, interface openings, and the failure modes.}, language = {en} } @inproceedings{TomićPennaDeJongetal.2020, author = {Tomić, Igor and Penna, Andrea and DeJong, Matthew and Butenweg, Christoph and Correia, Ant{\´o}nio A. and Candeias, Paulo X. and Senaldi, Ilaria and Guerrini, Gabriele and Malomo, Daniele and Beyer, Katrin}, title = {Seismic testing of adjacent interacting masonry structures}, series = {12th International Conference on Structural Analysis of Historical Constructions (SAHC 2020)}, booktitle = {12th International Conference on Structural Analysis of Historical Constructions (SAHC 2020)}, doi = {10.23967/sahc.2021.234}, pages = {1 -- 12}, year = {2020}, abstract = {In many historical centres in Europe, stone masonry buildings are part of building aggregates, which developed when the layout of the city or village was densified. In these aggregates, adjacent buildings share structural walls to support floors and roofs. Meanwhile, the masonry walls of the fa{\c{c}}ades of adjacent buildings are often connected by dry joints since adjacent buildings were constructed at different times. Observations after for example the recent Central Italy earthquakes showed that the dry joints between the building units were often the first elements to be damaged. As a result, the joints opened up leading to pounding between the building units and a complicated interaction at floor and roof beam supports. The analysis of such building aggregates is very challenging and modelling guidelines do not exist. Advances in the development of analysis methods have been impeded by the lack of experimental data on the seismic response of such aggregates. The objective of the project AIMS (Seismic Testing of Adjacent Interacting Masonry Structures), included in the H2020 project SERA, is to provide such experimental data by testing an aggregate of two buildings under two horizontal components of dynamic excitation. The test unit is built at half-scale, with a two-storey building and a one-storey building. The buildings share one common wall while the fa{\c{c}}ade walls are connected by dry joints. The floors are at different heights leading to a complex dynamic response of this smallest possible building aggregate. The shake table test is conducted at the LNEC seismic testing facility. The testing sequence comprises four levels of shaking: 25\%, 50\%, 75\% and 100\% of nominal shaking table capacity. Extensive instrumentation, including accelerometers, displacement transducers and optical measurement systems, provides detailed information on the building aggregate response. Special attention is paid to the interface opening, the globa}, language = {en} } @inproceedings{MorandiButenwegBreisetal.2022, author = {Morandi, Paolo and Butenweg, Christoph and Breis, Khaled and Beyer, Katrin and Magenes, Guido}, title = {Behaviour factor q for the seismic design of URM buildings}, series = {The Third European Conference on Earthquake Engineering and Seismology}, booktitle = {The Third European Conference on Earthquake Engineering and Seismology}, editor = {Arion, Christian and Scupin, Alexandra and Ţigănescu, Alexandru}, isbn = {978-973-100-533-1}, pages = {1184 -- 1194}, year = {2022}, abstract = {Recent earthquakes showed that low-rise URM buildings following codecompliant seismic design and details behaved in general very well without substantial damages. Although advances in simulation tools make nonlinear calculation methods more readily accessible to designers, linear analyses will still be the standard design method for years to come. The present paper aims to improve the linear seismic design method by providing a proper definition of the q-factor of URM buildings. Values of q-factors are derived for low-rise URM buildings with rigid diaphragms, with reference to modern structural configurations realized in low to moderate seismic areas of Italy and Germany. The behaviour factor components for deformation and energy dissipation capacity and for overstrength due to the redistribution of forces are derived by means of pushover analyses. As a result of the investigations, rationally based values of the behaviour factor q to be used in linear analyses in the range of 2.0 to 3.0 are proposed.}, language = {en} }