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Structural health monitoring is the process of implementing a continuous damage detection strategy to optimize the inspection and maintenance schedules of bridges, and extend their lifespans. One of the main challenges of automated damage detection is the lack of data on damaged states, which makes it difficult to validate new approaches in the research and development stage. To alleviate this problem, a monitoring campaign on a two‐span test bridge with defined defects is conducted and documented in this article. The bridge is a steel‐concrete composite structure with a length of 30 m, with two primary steel girders and a segmented concrete deck. The recorded data capture the long‐term ambient data from 18 test days and changing environmental conditions, as well as the short‐term ambient data and dynamic load tests from four damage scenarios with well‐defined damage extents. A mobile measurement system with numerous sensors is used for data acquisition. A shaker is placed on the bridge to excite white noise. The main goal of this article is to document the experimental procedure and perform preliminary plausibility checks on the measured data. First results demonstrate that system response data and environmental conditions are recorded reliably and that environmental effects significantly affect the long‐term measurements. Therefore, a suitable data set is provided as open‐source data for future studies on data normalization and automated damage detection. [ABSTRACT FROM AUTHOR]

Rail connection of the Fehmarn Belt fixed link – foundation relevant geotechnical special features The rail connection of the Fehmarn Belt fixed link is one of the top 3 railway construction projects in Europe. The aim is to guarantee continuous and fully electrified rail connection between Scandinavia and Germany. In the context of the approx. 88 km long railway, beside the rail track many civil engineering structures are to be constructed. Therefore, for all structures soil investigations are necessary to provide a fundamental basis for the planning process. Thus, for several years extensive soil investigation campaigns are carried out to evaluate the soil conditions in the project area. Due to the glacial history in eastern Schleswig‐Holstein the soil conditions are often very variable and inhomogeneous which leads to big challenges within the planning process. In the present article, the geological and geotechnical challenges in the present project are discussed on the basis of several exemplary situations and some solutions to overcome these challenges are briefly outlined. [ABSTRACT FROM AUTHOR]

Design approach against failure of the earth support using the finite element method The application of the finite element method (FEM) in geotechnical engineering has been established in the last decades for the prediction of deformations in the serviceability limit state (SLS). In practice, stability analyses in the ultimate limit state (ULS) are only partially performed using the FEM and are currently still state of the art. The next generation of Eurocode 7 is intended to regulate numerical methods with regard to their application in the ULS. However, the handling of the additionally required analysis of the German National Annex and DIN 1054 is still unsolved. In this paper, an approach for the numerical analysis of the earth support is presented. Following the well‐established strength reduction method, the weight of the soil γ and the cohesion c' ${{c}^{{ {\prime}}}}$ on the earth resistance side are reduced until failure occurs. On the basis of this, the analysis in ULS is carried out by defining a safety factor for the existing embedment depth of the retaining wall. This is followed by a comparison with the analytical free earth support method, identifying system reserves using the FEM. [ABSTRACT FROM AUTHOR]

Copyright of Bautechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geotechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geotechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Development of a Python script for strength reduction with numerical methods The application of numerical methods in geotechnics until now is mostly limited to the prediction of the deformation behaviour of structures regarding the serviceability limit state. The ultimate limit state has so far been handled rudimentarily (e.g. for homogeneous slopes and piled raft foundations), using numerical methods, such as the finite element method. In the present paper, therefore, the basis for the application of a unified method for parallel strength reduction on structural elements and a reduction of the shear parameters of the soil is discussed. In a first parametric study, a script based on the Python programming language for reducing the shear parameters of the soil is verified by comparison with approved methods for calculating the overall stability of slopes. Subsequently, the application boundaries of the Python script are extended to reduce the strength parameters of structural elements within a slope at risk of stability in the framework of a second parametric study. Based on this, an assessment of probable first failure mechanism (soil or structural failure) is made. Finally, the results of the two parametric studies are put into a causal context, considering a numerical verification with discussion of future research approaches. [ABSTRACT FROM AUTHOR]

Building Information Modeling – attribution of the specialized model subsoil The BMVI's "Stufenplan" has made the use of Building Information Modeling (BIM) mandatory for public infrastructure projects from 2020 onward, however this requirement is not yet fully met in practice. In the BIM‐based planning process, the geotechnical expert creates the specialized model subsoil. This article takes an approach to its structure based on submodels and their content. The focus is on the presentation of the relevant steps for finding a target‐oriented and BIM‐compliant attribution, considering the special features of the specialized model. For this purpose, its life cycle and the special features compared to other specialized models are illuminated. A proposal for dealing with soil‐structure interaction in the BIM‐supported planning process is presented. Finally, the necessity of attribute catalogs is discussed and ideas for their design are presented. [ABSTRACT FROM AUTHOR]

Chances and frontiers of numerical methods in geotechnics The use of numerical methods has become common practice in geotechnical engineering to solve complex tasks, with the finite element method (FEM) having gained the greatest importance. The article wants to inform about the possibilities and limits of numerical methods in geotechnics and to help in reducing any remaining reservations against the application of numerical methods in geotechnics. Following an overview of the manifold fields of application of numerical methods, special features of modelling in geotechnics are explained. These are, among other things, the necessary abstractions of the real building ground in a numerical model, the size of the calculation area or the consideration of the soil‐structure interaction. The special importance of material modelling of soil and rock is discussed in detail and an overview of the current developments of constitutive models and their parameter determination is given. FEM is currently also increasingly used for the design of geotechnical structures. The principles for design in geotechnical engineering using numerical methods, which are discussed in the context of current standardisation initiatives, are described and evaluated. Aspects related to Building Information Modeling (BIM) are also examined. Finally, the necessity of specialized userś qualification in order to apply the numerical methods purposefully and safely is pointed out. [ABSTRACT FROM AUTHOR]

Copyright of Geotechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerical investigation on the influence of reaction piles regarding static load test results The present paper investigates the influence of reaction piles on the load‐settlement behavior of the test pile during static load testing by means of a numerical study using FEM. In this investigation mainly the parameters distance between piles, pile length, length of reaction piles in comparison to the test pile's length as well as the number of reaction piles are varied. It is found out that the recommendations of the working group piles (EA Pfähle) regarding the minimum distance between test and reaction piles is not sufficient to avoid an influence of the reaction piles on the test pile's bearing behavior. [ABSTRACT FROM AUTHOR]

Copyright of Geotechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Für die Errichtung von Windparks ist der Einsatz von Offshore-Hubplattformen Stand der Technik. Die Hubplattform installiert sich vor dem eigentlichen Arbeiten auf dem Meeresgrund, um ausreichende Stabilität für die Arbeiten zu haben und den Einfluss des Seegangs zu minimieren. Eine mögliche Gründungsvariante für die Beine einer Offshore-Hubplattform ist die sogenannte Spudcan-Lösung. Hierbei wird ein Kreisfundament mit großem Durchmesser am Bein der Hubplattform befestigt, über das die Gründungslasten abgetragen werden. Der Einsatz derartiger Gründungen ist im internationalen Öl- und Gasbereich gängig und erprobt. Dennoch ist bereits die korrekte Bemessung der vertikalen Tragfähigkeit der Spudcans komplex. So ist zum Beispiel die Bestimmung der Last-Setzungskurve bei unterschiedlichen Baugrundverhältnissen schwierig und die Definition der 'sicheren Seite' ebenfalls nicht eindeutig. Ein weiteres Problem, welches bei Absetzen auf geschichtetem Baugrund auftreten kann, ist der sogenannte 'punch-through', d. h. bei beispielsweise dicht gelagertem Sand über weichem Boden kann es zu einem plötzlichen Durchstanzen der Plattform in die Weichschicht kommen, was bis hin zum Verlust der Plattform führen kann. In diesem Beitrag werden verschiedene Bemessungsansätze aus der Literatur und internationale Richtlinien zur Bemessung von Spudcans vorgestellt. Zudem werden offene Fragestellungen und Ansätze aus der Forschung diskutiert. Diese sollen dem Leser einen Eindruck über die Möglichkeiten von Spudcan-Gründungen geben und ihn gleichzeitig für mögliche Problemstellungen sensibilisieren. Spudcans as foundations for offshore jack-up rigs - Problems and calculation methods For the installation of wind parks jack-up rigs can be used. Jack-up rigs are founded on the seabed before start of operation to receive sufficient stability and to reduce wave induced influences. One possible foundation for jack-up rigs on the seabed is the so-called spudcan. A spudcan is a circular foundation attached to the legs of the jack-up rig to transfer the vertical loads into the ground. The use of spudcan-foundations is state-of-the-art in the oil- and gas industry. Nevertheless, the design of this type of foundation is still challenging. For example, the correct determination of the load-settlement-response with respect to different soil conditions is complex and the definition of the 'safe side' is not always clear. Another problem related to the spudcan depositioning onto layered soil is the so-called 'punch-through'-failure. This means that during installation onto dense sand overlying weak clay the spudcan may suddenly punch through the sand layer into the weaker layer. This can even lead to a total loss of the jack-up rig. In this contribution, different methods for spudcan design recommended in literature and international guidelines are summarized. Furthermore, open questions and results of ongoing research are discussed to give the reader an impression of the capabilities and the difficulties regarding spudcan foundations. [ABSTRACT FROM AUTHOR]

Copyright of Geotechnik is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)