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Translation abstract A mechanically consistent approach for stability verification of timber beams in compression and bending around the strong axis – part 2: experimental tests and numerical simulationSlender timber beams in bending can be designed using different methods in view of out‐of‐plane stability. Lateral torsional buckling may be verified either using the so called equivalent member method or by means of 2nd order calculations, considering equivalent imperfections. Applying current codes, however, determining the lateral torsional buckling resistance using either of these both methods, leads to different results. In this paper, the background of both verifications is investigated in deep. Moreover, as an alternative approach, a non‐linear calculation with an imperfection shape in affinity to the critical shape was presented in part 1 of this paper. By scaling the curvature, the same results as by the equivalent member method can be achieved. It was shown that plasticity effects can be considered as well. In this part 2, results of lateral torsional buckling tests on glued laminated timber beams are presented, with nearly ideal boundary conditions and load direction remaining vertical through‐out the test. Based on these test first tentative values can be obtained for the imperfection compatible with the alternative lateral torsional buckling approach presented. [ABSTRACT FROM AUTHOR]

Tests on sandwich façades as a basis for seismic design As part of an ongoing research project, the performance of lightweight metal façade elements under in‐plane loading was investigated to assess their cyclic behavior, dissipation capacity and functionality during seismic events. As preliminary investigations showed, metal wall and roof elements contribute to the stiffening of the overall structure, and thus to the change of the eigen period compared to the primary structure, which can lead to increased seismic loads to be applied acc. to the response spectrum method. Based on this, a new behavior‐based approach considering the contribution of lightweight metal building envelopes can be developed to determine the improved resilience of structures and the effect of a damaging earthquake on the building envelope performance. This paper includes: (i) a brief state of the art, (ii) a presentation of the research project, (iii) the experimental program, (iv) the detailed experimental setup, (v) the system response under monotonic and cyclic loading, (vi) the main results, (vii) an overview of the numerical investigations and ongoing and future research activities. [ABSTRACT FROM AUTHOR]

(Steel) bridges have well‐known issues with regard to fatigue problems causing a lot of the existing infrastructure to be urgently being strengthened or even being replaced. To supervise and investigate all bridges it is state of the art that on a regular basis these bridges have to be inspected by experts (German DIN 1076). In particular with regard to those already known issues a research consortium has set up a collaborative research project together with partners from the road authorities with the aim to provide a data system for an asset‐management for such bridges. The partners and road authorities have selected some typical bridges with regard to those particular structural details: • Cluster 1: „Coupling joints" (Pretensioned Concrete bridges) • Cluster 2: „Orthotropic steel decks" • Cluster 3: „Hangers/Cables" (Suspension bridges and steel arch bridges) This contribution will demonstrate that for six selected bridges of cluster 2 and 3 RWTH Aachen has developed detailed numerical models, investigated those critical details with regard to fatigue and proposed monitoring specifications. The relevant design checks of those critical details follow the design rules (in particular fatigue load model 3 of Eurocode) and with the installation of those monitoring concepts the evaluation of the fatigue critical details can be matched using hotspot analysis. [ABSTRACT FROM AUTHOR]

As recent research findings evidenced a significant potential of the steel‐concrete hybrid coupled wall (HCW) systems, further research activities are still needed for addressing particular issues and for developing advancements in the analysis, design, and detailing. These aspects are currently being addressed within the ongoing European research project "HYCAD", which also represents the research framework of the current study. This paper investigates through a set of nonlinear static and dynamic analyses the behavior and the seismic performance of a newly introduced steel‐concrete HCW system. In particular, a case‐study was carried out on a 3D multi‐story building structure with perimeter lateral load resisting frames, each composed of: (i) a HCW, i.e. a steel‐concrete composite wall coupled to steel columns through a set of replaceable steel shear links; (ii) a moment resisting frame (MRF). Beside a brief state of the art, a description of the research framework and the case‐study structural system, the current paper makes an overview of the following: (i) experimental program on components; (ii) proposed technical solution for connecting the replaceable dissipative shear links to the composite wall; (iii) experimental test set‐up; (iv) response of the shear links based on pretest FE investigations; (v) seismic demand in terms of rotation for the shear links. [ABSTRACT FROM AUTHOR]

Strong earthquake loads can cause significant damage to buildings, but even moderate earthquakes with higher return periods are socially relevant as they may cause both infrastructure and economic failures. In an ongoing German nationally funded research project, the behavior of facade elements in lightweight metal construction under in‐plane deformation is currently being investigated with the aim to assess the response and the energy dissipation capacity in the case of seismic events. As past research results indicate the contribution of wall and roof elements to the stiffening of buildings, with the possible consequence of increased earthquake loads due to the natural frequency change, a novel approach for increased resilience of structures with building envelopes in lightweight metal construction may be developed. On the basis of a series of experimental tests, under monotonic and cyclic loading, the effects of in‐plane deformation were studied separately from external influences such as wind and thermal loads. This paper presents: (i) a brief state of the art; (ii) a description of the research framework; (iii) the experimental program; (iv) the specimen configuration, test set‐up, loading protocol and instrumentation; (v) the response under monotonic and cyclic loading; (vi) the main conclusions, as well as the ongoing and future research activities. [ABSTRACT FROM AUTHOR]

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Owing to the new rules of the German National Annex to EN 1998‐1, the relevance of the seismic action has increased, materialising in extended seismic areas and higher spectral accelerations. This may lead to seismic loading being decisive on the design of steel and composite frames. However, the demand is lower in Germany than in other seismic areas. Consequently, these challenges are addressed in an ongoing German national research project, by developing joints with dissipative connections, classified as semi‐rigid and partial‐strength, for steel and composite frames that could allow for the use of behaviour factors in the range of 1.5 to 3. The development started with typical connections from the German catalogue, designed to withstand static loads in the elastic range, followed by performance and detailing improvements. Developments (e.g., increase in sagging/hogging bending: 125 %/18 % of steel joints and 70 %/40 % of partially composite joints) resulted from pre‐test finite element analyses (FEA) on joints and frame models. Improvements to joint detailing were made according to the provisions of the newest draft of Eurocode 8. The optimised joints were integrated in frame specimens, which are currently being tested under monotonic and cyclic loads at RWTH‐Aachen University. This article introduces the developed joint solutions, describes the experimental and numerical programs and presents the monotonic response of frame specimens based on the results of FEA, as well as the main conclusions. [ABSTRACT FROM AUTHOR]