TY  - JOUR
A1  - Baumgartner, Werner
A1  - Fidler, Florian
A1  - Weth, Agnes
A1  - Habbecke, Martin
A1  - Jakob, Peter
A1  - Butenweg, Christoph
A1  - Böhme, Wolfgang
T1  - Investigating the locomotion of the sandfish in desert sand using NMR-Imaging
JF  - PLOS ONE
N2  - The sandfish (Scincus scincus) is a lizard having the remarkable ability to move through desert sand for significant distances. It is well adapted to living in loose sand by virtue of a combination of morphological and behavioural specializations. We investigated the bodyform of the sandfish using 3D-laserscanning and explored its locomotion in loose desert sand using fast nuclear magnetic resonance (NMR) imaging. The sandfish exhibits an in-plane meandering motion with a frequency of about 3 Hz and an amplitude of about half its body length accompanied by swimming-like (or trotting) movements of its limbs. No torsion of the body was observed, a movement required for a digging-behaviour. Simple calculations based on the Janssen model for granular material related to our findings on bodyform and locomotor behaviour render a local decompaction of the sand surrounding the moving sandfish very likely. Thus the sand locally behaves as a viscous fluid and not as a solid material. In this fluidised sand the sandfish is able to “swim” using its limbs.
KW  - magnetic resonance imaging
KW  - body limbs
KW  - swimming
KW  - lizards
KW  - deserts
Y1  - 2008
U6  - http://dx.doi.org/10.1371/journal.pone.0003309
SN  - 1932-6203
VL  - 3
IS  - 10
PB  - Plos
CY  - San Francisco, California, US
ER  - 
TY  - JOUR
A1  - Frauenrath, Tobias
A1  - Hezel, Fabian
A1  - Heinrichs, Uwe
A1  - Kozerke, Sebastian
A1  - Utting, Jane
A1  - Kob, Malte
A1  - Butenweg, Christoph
A1  - Boesiger, Peter
A1  - Niendorf, Thoralf
T1  - Feasibility of Cardiac Gating Free of Interference With Electro-Magnetic Fields at 1.5 Tesla, 3.0 Tesla and 7.0 Tesla Using an MR-Stethoscope
JF  - Investigative Radiology
KW  - phonocardiogram
KW  - electrocardiogram
KW  - cardiac gating
KW  - high field MR imaging
KW  - cardiovascular MR imaging
Y1  - 2009
U6  - http://dx.doi.org/10.1097/RLI.0b013e3181b4c15e
SN  - 1536-0210 (online)
SN  - 0020-9996 (gedruckt)
VL  - 44
IS  - 9
SP  - 539
EP  - 547
PB  - Lippincott Williams & Wilkins ; (via Ovid)
CY  - Philadelphia, Pa
ER  - 
TY  - JOUR
A1  - Becker, Meike
A1  - Frauenrath, Tobias
A1  - Hezel, Fabian
A1  - Krombach, Gabriele A.
A1  - Kremer, Ute
A1  - Koppers, Benedikt
A1  - Butenweg, Christoph
A1  - Goemmel, Andreas
A1  - Utting, Jane F.
A1  - Schulz-Menger, Jeanette
A1  - Niendorf, Thoralf
T1  - Comparison of left ventricular function assessment using phonocardiogram- and electrocardiogram-triggered 2D SSFP CINE MR imaging at 1.5 T and 3.0 T
JF  - European Radiology
N2  - Objective: As high-field cardiac MRI (CMR) becomes more widespread the propensity of ECG to interference from electromagnetic fields (EMF) and to magneto-hydrodynamic (MHD) effects increases and with it the motivation for a CMR triggering alternative. This study explores the suitability of acoustic cardiac triggering (ACT) for left ventricular (LV) function assessment in healthy subjects (n=14). Methods: Quantitative analysis of 2D CINE steady-state free precession (SSFP) images was conducted to compare ACT’s performance with vector ECG (VCG). Endocardial border sharpness (EBS) was examined paralleled by quantitative LV function assessment. Results: Unlike VCG, ACT provided signal traces free of interference from EMF or MHD effects. In the case of correct Rwave recognition, VCG-triggered 2D CINE SSFP was immune to cardiac motion effects—even at 3.0 T. However, VCG-triggered 2D SSFP CINE imaging was prone to cardiac motion and EBS degradation if R-wave misregistration occurred. ACT-triggered acquisitions yielded LV parameters (end-diastolic volume (EDV), endsystolic volume (ESV), stroke volume (SV), ejection fraction (EF) and left ventricular mass (LVM)) comparable with those derived fromVCG-triggered acquisitions (1.5 T: ESVVCG=(56± 17) ml, EDVVCG=(151±32)ml, LVMVCG=(97±27) g, SVVCG=(94± 19)ml, EFVCG=(63±5)% cf. ESVACT= (56±18) ml, EDVACT=(147±36) ml, LVMACT=(102±29) g, SVACT=(91± 22) ml, EFACT=(62±6)%; 3.0 T: ESVVCG=(55±21) ml, EDVVCG=(151±32) ml, LVMVCG=(101±27) g, SVVCG=(96±15) ml, EFVCG=(65±7)% cf. ESVACT=(54±20) ml, EDVACT=(146±35) ml, LVMACT= (101±30) g, SVACT=(92±17) ml, EFACT=(64±6)%). Conclusions: ACT’s intrinsic insensitivity to interference from electromagnetic fields renders
KW  - Magnetic resonance imaging (MRI)
KW  - MR-stethoscope
KW  - Magnetic field strength
KW  - Left ventriular function
KW  - Cardiovascular MRI
Y1  - 2010
U6  - http://dx.doi.org/10.1007/s00330-009-1676-z
SN  - 1432-1084 (Onlineausgabe)
SN  - 0938-7994 (Druckausgabe)
VL  - 20
SP  - 1344
EP  - 1355
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Butenweg, Christoph
A1  - Heuer, R.
A1  - Wenk, T.
T1  - Erdbebeningenieurwesen und Baudynamik
T1  - Earthquake engineering and structural dynamics (editorial)
JF  - Bauingenieur
Y1  - 2015
SN  - 00056650
VL  - 90
IS  - 10
SP  - S1
PB  - VDI Fachmedien
CY  - Düsseldorf
ER  - 
TY  - JOUR
A1  - Giresini, Linda
A1  - Sassu, Mauro
A1  - Butenweg, Christoph
A1  - Alecci, Valerio
A1  - De Stefano, Mario
T1  - Vault macro-element with equivalent trusses in global seismic analyses
JF  - Earthquakes and Structures
N2  - This paper proposes a quick and simplified method to describe masonry vaults in global seismic analyses of buildings. An equivalent macro-element constituted by a set of six trusses, two for each transverse, longitudinal and diagonal direction, is introduced. The equivalent trusses, whose stiffness is calculated by fully modeled vaults of different geometry, mechanical properties and boundary conditions, simulate the vault in both global analysis and local analysis, such as kinematic or rocking approaches. A parametric study was carried out to investigate the influence of geometrical characteristics and mechanical features on the equivalent stiffness values. The method was numerically validated by performing modal and transient analysis on a three naves-church in the elastic range. Vibration modes and displacement time-histories were compared showing satisfying agreement between the complete and the simplified models. This procedure is particularly useful in engineering practice because it allows to assess, in a simplified way, the effectiveness of strengthening interventions for reducing horizontal relative displacements between vault supports.
KW  - vault
KW  - macro-element
KW  - equivalent stiffness
KW  - truss
KW  - churches
Y1  - 2017
U6  - http://dx.doi.org/10.12989/eas.2017.12.4.409
SN  - 2092-7614 (Print)
SN  - 2092-7622 (Online)
VL  - 12
IS  - 4
SP  - 409
EP  - 423
PB  - Techno-Press
CY  - Taejŏn
ER  - 
TY  - JOUR
A1  - Marinkovic, Marko
A1  - Butenweg, Christoph
T1  - Numerical analysis of the in-plane behaviour of decoupled masonry infilled RC frames
JF  - Engineering Structures
N2  - Damage of reinforced concrete (RC) frames with masonry infill walls has been observed after many earthquakes. Brittle behaviour of the masonry infills in combination with the ductile behaviour of the RC frames makes infill walls prone to damage during earthquakes. Interstory deformations lead to an interaction between the infill and the RC frame, which affects the structural response. The result of this interaction is significant damage to the infill wall and sometimes to the surrounding structural system too. In most design codes, infill walls are considered as non-structural elements and neglected in the design process, because taking into account the infills and considering the interaction between frame and infill in software packages can be complicated and impractical. A good way to avoid negative aspects arising from this behavior is to ensure no or low-interaction of the frame and infill wall, for instance by decoupling the infill from the frame. This paper presents the numerical study performed to investigate new connection system called INODIS (Innovative Decoupled Infill System) for decoupling infill walls from surrounding frame with the aim to postpone infill activation to high interstory drifts thus reducing infill/frame interaction and minimizing damage to both infills and frames. The experimental results are first used for calibration and validation of the numerical model, which is then employed for investigating the influence of the material parameters as well as infill’s and frame’s geometry on the in-plane behaviour of the infilled frames with the INODIS system. For all the investigated situations, simulation results show significant improvements in behaviour for decoupled infilled RC frames in comparison to the traditionally infilled frames.
KW  - Seismic loading
KW  - Earthquake
KW  - In-plane performance, isolation
KW  - Infill wall design
KW  - Numerical modelling
Y1  - 2022
U6  - http://dx.doi.org/10.1016/j.engstruct.2022.114959
SN  - 0141-0296
VL  - 272
IS  - 1
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Butenweg, Christoph
A1  - Marinković, Marko
A1  - Kubalski, Thomas
A1  - Fehling, Ekkehard
A1  - Pfetzing, Thomas
A1  - Meyer, Udo
ED  - Voss, Michael
T1  - Auslegung von Stahlbetonrahmentragwerken mit Ausfachungen aus Ziegelmauerwerk (Teil 2)
T1  - Design of reinforced concrete enclosures infilled with clay block masonry (Part 2)
JF  - Ziegelindustrie international : ZI = Brick and tile industry international
N2  - Im Rahmen des europäischen Verbundprojekts INSYSME wurden von den deutschen Partnern die Systeme IMES und INODIS zur Verbesserung des seismischen Verhaltens von ausgefachten Stahlbetonrahmen entwickelt. Ziel beider Systeme ist es, Stahlbetonrahmen und Ausfachung zu entkoppeln, anstatt die Tragfähigkeit durch aufwendige und kostspielige zusätzliche Bewehrungseinlagen zu erhöhen. Erste Ergebnisse des Systems IMES für Belastungen in und senkrecht zu der Wandebene werden vorgestellt.
N2  - Within the scope of the joint European project INSYSME, the German partners developed two systems - IMES and INODIS - for improving the seismic behaviour of masonry infilled reinforced concrete frames. The purpose of both systems is to decouple frame and infill instead of working to improve their load-bearing capacity by means of elaborate, expensive, supplementary reinforcing elements. Initial findings for the IMES system with regard to the loads acting in-plane and perpendicular to the wall plane (out-of-plane) are presented.
Y1  - 2018
SN  - 0341-0552
IS  - 6
SP  - 24
EP  - 43
PB  - Bauverlag BV GmbH
CY  - Gütersloh
ER  - 
TY  - JOUR
A1  - Butenweg, Christoph
A1  - Marinković, Marko
A1  - Kubalski, Thomas
A1  - Fehling, Ekkehard
A1  - Pfetzing, Thomas
A1  - Meyer, Udo
ED  - Voss, Michael
T1  - Auslegung von Stahlbetonrahmentragwerken mit Ausfachungen aus Ziegelmauerwerk (Teil 1)
T1  - Design of reinforced concrete enclosures infilled with clay block masonry (Part 1)
JF  - Ziegelindustrie international : ZI = Brick and tile industry international
N2  - Im Rahmen des europäischen Verbundprojekts INSYSME wurden von den deutschen Partnern die Systeme IMES und INODIS zur Verbesserung des seismischen Verhaltens von ausgefachten Stahlbetonrahmen entwickelt. Ziel beider Systeme ist es, Stahlbetonrahmen und Ausfachung zu entkoppeln, anstatt die Tragfähigkeit durch aufwendige und kostspielige zusätzliche Bewehrungseinlagen zu erhöhen. Erste Ergebnisse des Systems IMES für Belastungen in und senkrecht zu der Wandebene werden vorgestellt.
N2  - Within the scope of the joint European project INSYSME, the German partners developed two systems - IMES and INODIS - for improving the seismic behaviour of masonry infilled reinforced concrete frames. The purpose of both systems is to decouple frame and infill instead of working to improve their load-bearing capacity by means of elaborate, expensive, supplementary reinforcing elements. Initial findings for the IMES system with regard to the loads acting in-plane and perpendicular to the wall plane (out-of-plane) are presented.
Y1  - 2018
SN  - 0341-0552
IS  - 4
SP  - 30
EP  - 39
PB  - Bauverlag BV GmbH
CY  - Gütersloh
ER  - 
TY  - JOUR
A1  - Šakić, Bogdan
A1  - Marinković, Marko
A1  - Butenweg, Christoph
A1  - Klinkel, Sven
ED  - Yang, J.
T1  - Influence of slab deflection on the out-of-plane capacity of unreinforced masonry partition walls
JF  - Engineering Structures
N2  - Severe damage of non-structural elements is noticed in previous earthquakes, causing high economic losses and posing a life threat for the people. Masonry partition walls are one of the most commonly used non-structural elements. Therefore, their behaviour under earthquake loading in out-of-plane (OOP) direction is investigated by several researches in the past years. However, none of the existing experimental campaigns or analytical approaches consider the influence of prior slab deflection on OOP response of partition walls. Moreover, none of the existing construction techniques for the connection of partition walls with surrounding reinforced concrete (RC) is investigated for the combined slab deflection and OOP loading. However, the inevitable time-dependent behaviour of RC slabs leads to high values of final slab deflections which can further influence boundary conditions of partition walls. Therefore, a comprehensive study on the influence of slab deflection on the OOP capacity of masonry partitions is conducted. In the first step, experimental tests are carried out. Results of experimental tests are further used for the calibration of the numerical model employed for a parametric study. Based on the results, behaviour under combined loading for different construction techniques is explained. The results show that slab deflection leads either to severe damage or to a high reduction of OOP capacity. Existing practical solutions do not account for these effects. In this contribution, recommendations to overcome the problems of combined slab deflection and OOP loading on masonry partition walls are given. Possible interaction of in-plane (IP) loading, with the combined slab deflection and OOP loading on partition walls, is not investigated in this study.
KW  - Masonry partition walls
KW  - Earthquake
KW  - Out-of-plane capacity
KW  - Slab deflection
Y1  - 2023
U6  - http://dx.doi.org/10.1016/j.engstruct.2022.115342
SN  - 0141-0296
VL  - 276
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Kubalski, Thomas
A1  - Butenweg, Christoph
A1  - El-Deib, Khaled
ED  - Jesse, Dirk
T1  - Vereinfachte Berücksichtigung der Rahmentragwirkung in Mauerwerksgebäuden
T1  - Simplified consideratioon of framing effects in masonry buildings
JF  - Bautechnik
N2  - Aufgrund der gestiegenen Anforderungen durch höhere Ein-wirkungen aus Wind und Erdbeben ist eine Verbesserung und Optimierung der Berechnungs- und Bemessungsansätze für Mauerwerksbauten erforderlich. Eine bessere Ausnutzung der Tragwerksreserven ist durch die Berücksichtigung der Rah-mentragwirkung mit einer Aktivierung der Deckenscheiben in den Rechenmodellen möglich, die in der Praxis aufgrund der Komplexität der Wand-Decken-Interaktion bislang nicht aus-genutzt wird. Im vorliegenden Aufsatz wird ein vereinfachter Ansatz auf Grundlage der mitwirkenden Plattenbreite von Schubwänden aus Mauerwerk vorgestellt, der die wesentli-chen Einfl ussfaktoren in parametrisierten Tabellen erfasst. Damit steht den Tragwerksplanern ein einfach anwendbares Werkzeug zur Verfügung, um die Rahmentragwirkung in der Mauerwerksbemessung anzusetzen.
N2  - Due to the increased requirements resulting from higher wind and earthquake loads, it is necessary to improve and optimise the calculation and design approaches for masonry structures. An important contribution to a better utilisation of the structural load-bearing reserves is the consideration of the framing ef-fects through the activation of the fl oor slabs in the calculation models, which has not been utilised in practice so far due to the complexity of the wall-slab interaction. The paper presents a simplifi ed approach based on the contributory slab width, which captures the essential infl uencing factors in parameter-ised tables. This provides structural engineers with a simple tool to exploit the frame load-bearing effect in masonry design.
KW  - Rahmentragwirkung
KW  - Mauerwerksgebäude
KW  - Wand-Decken-Interaktion
KW  - Momentenverteilung
KW  - DIN EN 1996
Y1  - 2022
U6  - http://dx.doi.org/10.1002/bate.202200081
SN  - 0932-8351
SN  - 1437-0999
VL  - 99
IS  - 12
SP  - 865
EP  - 928
PB  - Ernst & Sohn
CY  - Berlin
ER  -