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Summary The significant cultural achievement of the development of the cultivation of Coca (Erythroxylum coca) by the indigenous South Americans was never adequately recognised by the European Conquerors. The aim of this paper is to demonstrate its importance for Western science by summarising its perception during the colonial period and the 19th century and reviewing the isolation of cocaine, its use as local anaesthetic, determination of its chemical structure and synthesis of substitutes as milestones of Western chemistry, pharmacy and medicine. Finally, it summarises the culturally impact of cocaine on the Western culture during the 20th century and the economic impact of coca production in South America. [ABSTRACT FROM AUTHOR]

According to a traditional interpretation of Kierkegaard, he endorses a strong form of direct doxastic voluntarism on which we can, by brute force of will, make a “leap of faith” to believe propositions that we ourselves take to be improbable and absurd. Yet most leading Kierkegaard scholars now wholly reject this reading, instead interpreting Kierkegaard as holding that the will can affect what we believe only indirectly. This paper argues that Kierkegaard does in fact endorse a restricted, sophisticated, and plausible version of direct doxastic voluntarism. On Kierkegaard's view, when we take ourselves to be in an epistemically permissive situation, we have the ability to form outright beliefs (but not credences) at will in virtue of our ability to voluntarily 1) open or close inquiry and 2) determine our attitude towards epistemic risk. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the contents of 2nd Generation Eurocode 7 Part 2, highlighting two of the major changes introduced, being the Ground Model and the Rock Engineering implementation. The document is organized from a ground property perspective so that the role of Part 2 and the links with the geotechnical design are much clearer than in the previous edition. Its new title is a clear indication of this idea: "Ground properties" including both soil and rock properties. The need to have representative values for the ground properties is the objective of this new Part 2, which is intended to guide designers on the path to obtain those values by means of the Desk Study, Site Inspection, Field Investigation and Laboratory Testing. Given this framework, the paper explains the concepts behind the Ground Model, the main output of the Ground Investigation, which includes the ground profile, the geometric properties of the ground and its layers, groundwater, and the derived values of the ground properties, paying attention of the role of discontinuities in such ground profile. The tasks that form the Ground Investigation and the minimum number of activities to be performed are described. This new version of EN 1997 will include a Rock Engineering perspective for all above items. And finally, the ground properties of the rock material and the rock mass are listed and discussed. [ABSTRACT FROM AUTHOR]

The current first generation of Eurocodes is a suite of ten European standards for the design of buildings and civil engineering works, whose implementation started in 2010. EN 1990 sets the basis of structural design, with the other Eurocodes dealing with different materials and specific aspects of design. Geotechnical aspects of design are covered by EN 1997 "Geotechnical design", usually called Eurocode 7. The evolution of the Eurocodes started in 2012 and the main objectives of their revision were to incorporate improvements that reflect the state‐of‐the‐art in engineering design and the needs of the civil engineering market, to improve the ease‐of‐use and to harmonize practice between countries. While the original version was developed largely based on soil mechanics, the aim was that the revised version treats soil and rock on an equal basis. The second generation of the Eurocodes is now nearly finished, and the revised EN 1997 is expected to be formally approved in 2024. This paper is the first of a set of six informative papers on the revised Eurocodes and rock engineering, prepared by members of the Rock Engineering Platform of CEN/TC250/SC7, a group of rock engineering experts that has been assisting in drafting EN 1997 from a rock‐engineering perspective. The paper presents the main changes to EN 1990 and EN 1997 as far as they affect geotechnical and rock engineering design. [ABSTRACT FROM AUTHOR]

Machine learning for design and analysis of steel frame halls The use of digital tools in design and construction processes increases efficiency, especially for recurring tasks and processes, such as the dimensioning of components or structures, which follow similar patterns. This paper develops an artificial intelligence (AI)‐based assistant for use in the pre‐design and design of steel frame halls as a prototypical co‐pilot. For this purpose, the necessary database of steel frame halls is first compiled from project archives of TRAGRAUM Partnerschaft Beratender Ingenieure mbB. This will be examined in the context of data analyses according to the decisive description parameters and similarities, so that finally suitable AI surrogate models for the prediction of the hall parameters are trained by means of regression analyses. Furthermore, an interface to the finite element program SOFiSTiK is implemented, which passes the predictions of the AI regarding the parameters of the steel frame halls to a parameterized input file and triggers the calculation and design. In the course of the calibration of the AI substitute models, in addition to the approximation qualities, possible safety margins to be provided are also discussed in the context of this article. This article shows that the prototypical co‐pilot for the preliminary design of steel frame halls could be successfully implemented. Furthermore the AI newly generated hall frames can be classified as stable with respect to the validation considerations. An outlook on future further developments of this approach as well as the transfer to other applications complete this paper. [ABSTRACT FROM AUTHOR]

Free‐form reinforced concrete, prestressed concrete and composite components: Calculation of cross‐section values A resource‐efficient use of concrete as a construction material can be achieved by adapting the individual shape of a component under consideration to the stresses that occur and by arranging composite construction materials (e. g. reinforcing steel, prestressing steel or structural steel) in suitable areas of the component. Due to the advancing digitalisation in the construction industry, for example in the context of Building Information Modeling, computer‐aided 3D modelling methods are increasingly being used in the planning of structures. These allow engineers to design components in free form. In reinforced concrete, prestressed concrete and composite construction, the design of such components is currently still associated with great effort. In the context of the development of a practical method for the calculation of free‐form concrete components, this paper presents a CAD‐integrated method for the calculation of cross‐section values. Cross‐section values are required as an essential calculation basis when real, three‐dimensional structural components are treated using simplified calculation theories, such as the beam theory. In this paper, the mathematical and numerical fundamentals of a method for the calculation of cross‐section values of free‐form concrete, reinforced concrete, prestressed concrete and compound components are presented. The calculation method is based on flat geometric regions described by Non‐uniform rational B‐Spline tensor product surfaces, which can be extracted from solid models, for example. [ABSTRACT FROM AUTHOR]

Modelling of the CUBE's TWIST shell This paper gives an overview of the main procedures prepared during the phase of the project development within the field of numerical modelling and design. The roof shell elements represent itself twisted shape that together with complicated structurally demanded inner structure forms quite complicated configuration for the concrete volumes as well as for the used reinforcement. Therefore, custom developed numerical method was required to be prepared. For that, the software solutions Rhinoceros 3D and Grasshopper 3D were used as the main algorithmic environment. The paper additionally gives an insight of important aspects required for production of the formwork components, thermal insulation, biaxially oriented carbon reinforcing grids and other parts of the load‐bearing shells. Finally, the paper gives an idea how was established a collaboration with partners of the CUBE project in particular in the field of structural analysis. [ABSTRACT FROM AUTHOR]

A mechanically consistent approach for stability verification of timber beams in compression and bending around the strong axis, part 1 – derivations Slender 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. However, at present 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 is presented in part 1 of this paper. If the curvature amplitude is scaled, the same results as by the equivalent member method are achieved. It is shown that plasticity effects can be considered with high precision as well. In part 2, results of experimental tests on lateral torsional buckling of glued laminated timber and laminated veneer lumber beams are presented, with nearly ideal boundary conditions and load 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]

Projects Tunnel construction work in the BBT Eisack underpass construction lot completed / Tunnelbauarbeiten im BBT‐Baulos Eisackunterquerung abgeschlossen Planning process for Frankfurt Inter‐city railway tunnel shortened / Planungsprozess für Fernbahntunnel Frankfurt beschleunigt Operational exercises before commissioning of the Koralm Railway / Einsatzübungen vor Inbetriebnahme der Koralmbahn Limberg 3 – Heavy transport in the mountain / Limberg 3 – Schwertransporte im Berg Second underground lot awarded for Hamburg U5 / Zweites U‐Bahnlos für Hamburger U5 vergeben Ligerz tunnel contract awarded as part of the Ligerz‐Twann double‐track extension project / Tunnel Ligerz im Rahmen des Doppelspurausbaus Ligerz‐Twann vergeben Max Bögl commissioned to produce and deliver segments for the Brenner Base Tunnel / Max Bögl mit Produktion und Lieferung von Tübbingen für den Brenner Basistunnel beauftragt Final breakthrough for the Silvertown Tunnel / Finaler Durchbruch für den Silvertown‐Tunnel STRABAG UK opens precast tunnel segment plant in Hartlepool / STRABAG UK eröffnet Fertigteilwerk für Tunnelsegmente in Hartlepool Extensive diaphragm wall work for Jakarta metro station / Umfangreiche Schlitzwandarbeiten für U‐Bahnstation in Jakarta Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

The current Eurocode revision process is sought to improve Eurocode 7 for application to rock engineering, while including only techniques and procedures that are in widespread customary use. The revision process has exposed much about the application of the Eurocodes to rock engineering, thereby offering hints as to what material should be included in the next revision – tentatively suggested for publication in 2035. Crucially, ideas have developed about how rock engineering practice may need to develop to embrace the principles on which the Eurocodes are based. In particular, aspects of determining the properties of rock masses, and design verification by observational methods, partial factors, numerical modelling, and prescriptive rules are all thought to require significant improvement or dramatic modification. This paper highlights challenges identified regarding the application of the Eurocodes to rock engineering, and which will need to be addressed in the future. Ideas are presented about how these challenges may be overcome, but these are given in the spirit of stimulating ongoing conversation within the rock mechanics and rock engineering community rather than presenting definite proposals. [ABSTRACT FROM AUTHOR]

In 2025 the new generation of the Eurocode 7 will be introduced and set a framework for geotechnical design for the next 20 years. As Eurocode 7 is an essential design code, the changes will affect numerous practising geotechnical Engineers. The paper provides an overview of significant changes in rock engineering design introduced in the new EN 1997 part 3, considering limit state design, durability, reliability, testing and other crucial design aspects. It focuses on the anchor clause revision and first introduced design rules for rock bolts and soil‐nailed structures. The improvements described include distinguishing between different tension supporting elements that have often been confused. Furthermore, the provisions for groundwater control measures influencing the working condition and limit states for all other geotechnical systems that have not yet been comprehensively addressed in the current Eurocode 7 are also clarified. Finally, the design of the described geotechnical structure will also be strongly affected by changes in the overall philosophy of the Eurocodes, which is also explained. [ABSTRACT FROM AUTHOR]

The second generation of Eurocode 7 includes both soil and rock. In addition to the current practice of ground engineering, this document aims at incorporating rock engineering, improving the ease of use, the harmonization of regulations and covering new developments. This paper provides an overview of some of the significant changes to Eurocode 7 in rock engineering design, taking into consideration limit state design, robustness, durability, and reliability. It focuses on the design of slopes, spread foundations, and retaining structures. The clauses focus on soil mechanics, but also include special rock mechanical issues such as the influence of discontinuities and strength anisotropy on the limit states. Many matters associated to verification of rock mechanical design are linked to the use of prescriptive rules and shall be given in National Annexes. For geotechnical structures in rock, it is mentioned that geotechnical mapping and documentation is important to verify the limit states. However, the basic issues with partial factor methods for verification of the ground‐structure interaction of reinforced slopes and retaining structures are not fully resolved. This has caused some difficulties in setting up partial factors and obtaining a sufficient overview of the application of partial factor method, especially in rock engineering. The design of slopes, spread foundations and retaining structures must likewise consider other clauses in the Eurocode. Rock support for slopes and retaining structures is described in Clause 13 "Rock Bolts and Surface Support". Groundwater‐related issues are described in clause 12 "Ground water control" which influence the design and limit states for the actual geotechnical structure. Dams and levees are featured in Clause 4 "Slopes, Cuttings and Embankments". [ABSTRACT FROM AUTHOR]

The second generation of Eurocode 7 aims at covering ground, including both soil and rock. Current practice of ground engineering forms the basis, and the aim is to include rock engineering, improving ease of use, harmonization of regulations, and covering new developments. This paper deals with EN 1997 part 1 addressing the general rules of geotechnical design, connected to EN 1990, the basis of structural and geotechnical design, and parts 2 and 3 of EN 1997. The design process from ground investigation to the verification of limit states is illustrated with a focus on rock engineering. The following topics are dealt with in more detail: Geotechnical Categories: They are now based on Consequence Classes and newly introduced Geotechnical Complexity Classes. A limit state design to be sufficient has to be combined with other checks depending on these classes.Replacement of the Design Approaches of the current Eurocode 7: Ultimate limit states will be verified by a combination of Verification Cases with partial factors on actions and action effects, and sets of partial factors on ground properties and resistances, respectively.Application of numerical methods, where a ULS‐verification with two sets of partial factors is defined.Use of probabilistic methods in design by calculation, especially appropriate in cases where properties of discontinuities govern the design.Practice of the Observational Method, including design variants and regulations about their choice. [ABSTRACT FROM AUTHOR]

Experiences with the application of the needle penetrometer test in marlstone The correct assessment of Unconfined Compressive Strength represents one of the core tasks in the context of the planning and execution of civil engineering, tunneling and geotechnical engineering works. However, in weak and non‐durable rock types, sampling, preservation of the natural water content, sample preparation and finally testing with standard laboratory testing methods, such as the Uniaxial Compressive Strength test, is challenging, if not impossible. As early as 1980, the needle penetrometer was developed in Japan as a field test method for estimating the Unconfined Compressive Strength of such rocks. Although the procedure is presented in an ISRM Suggested Method published in 2014, the use of the needle penetrometer and the needle penetrometer index (NPI) is rather unusual in Germany and Central Europe. The paper resumes the results of a large number of tests carried out in the course the geotechnical investigation of pile drilling works in marlstones of the Upper Cretaceous in the vicinity of Münster/Germany. Based on this experience, the article presents an analysis of the potential area of application and comments on the correlation of testing results and Unconfined Compressive Strength. [ABSTRACT FROM AUTHOR]

How safe are our structures? – Conceptual paper of the DGGT Working Group 2.15 "Reliability‐Based Methods in Geotechnical Engineering" The future Eurocode 7 will explicitly allow the use of reliability‐based methods in geotechnical planning and design. In Germany, there is hardly any experience in the practical application of such methods so far and thus the reservations towards these methods are plenty. The new DGGT Working Group (WG) 2.15 "Reliability‐Based Methods in Geotechnical Engineering" has set itself the goal of providing a practical access to those methods by means of practice‐oriented instructions and recommendations as well as accompanying training and further education courses. The aim is to clarify the possibilities and limitations and, above all, to exploit their potential. This article presents the general principles as well as the future fields of work of the WG 2.15. Starting with the introduction of relevant technical terms, the implementation of reliability‐based methods within the current codes of practice and regulations is shown. Using the life cycle of a geotechnical structure, the uncertainties in geotechnical designs and assessments are described. Subsequently it is outlined, in which situations and to what extend reliability‐based methods can aid engineers, clients and inspectors in verification and decision‐making processes. In the future, WG 2.15 will develop recommendations on individual topics and publish them successively. [ABSTRACT FROM AUTHOR]

Projects Starting the second tunnel boring machine at the Brenner construction site Sillschlucht‐Pfons / Andrehen der zweiten Tunnelbohrmaschine am Brenner‐Baulos Sillschlucht‐Pfons Contracts for caverns and gallery system for Forbach pumped storage power station awarded / Kavernen und Stollensystem für Pumpspeicherkraftwerk Forbach beauftragt Brenner north approach: gallery construction between Schaftenau and Radfeld / Brenner‐Nordzulauf: Stollenbau zwischen Schaftenau und Radfeld First part of the Fehmarnbelt tunnel concreted / Erster Teil des Fehmarnbelt‐Tunnels betoniert EU funds Brenner Base Tunnel with another 700 million euros / EU fördert Brenner Basistunnel mit weiteren 700 Mio. Euro Four international consortia have been selected for railway equipment of the Fehmarnbelt Tunnel / Vier internationale Konsortien für bahntechnsiche Ausrüstung des Fehmarnbelt‐Tunnel ausgewählt Porr wins a major contract for the SuedLink Elbe crossing / Porr gewinnt Großauftrag für SuedLink Elbquerung Lucerne through station: preliminary project completed / Durchgangsbahnhof Luzern: Vorprojekt abgeschlossen Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Influence of the arrangement of the punching shear and composite reinforcement made of L steel plates on the load‐bearing capacity The CLIXS punching shear and composite reinforcement system consists of L steel plates with one or two connected stirrups made of reinforcing steel. It is possible to increase the load‐bearing capacity by more than twice the load‐bearing capacity without punching shear reinforcement. The experimental investigations described in the paper were carried out on square slab cut‐outs with a length of 2.8 m and a thickness of 18 and 25 cm. The load‐bearing capacity as a function of the number of uniform arranged L steel plates was determined based on 17 experiments. For this purpose, test specimen with 6 L steel plates up to 36 L steel plates in the first three perimeters were investigated. In addition, 10 test specimen with different sized areas without L steel plates were tested. The areas without L steel plates were between 25 % and 75 % of the area within the first three perimeters. The use of stirrups with a diameter of 8 mm instead of 6 mm was investigated using two test specimens. [ABSTRACT FROM AUTHOR]

Investigation of an engineering model for the assessment of the seismic behaviour of large mobile equipment For large mobile equipment in seismically active regions, seismic stability is an essential and often decisive design criterion. The seismic behaviour of such large equipment is usually characterised by complex nonlinear types of behaviour (uplift, tilting and rocking), which are difficult to compute and analyse in practice. In this paper, a highly simplified engineering model is presented or developed step by step, which should be able to represent basic features of the typical behaviour of large mobile equipment transverse to the rail under seismic excitation. The typical rocking motion of the equipment, as determined in previous analyses, is to be reflected in the simplified model. The engineering model will be designed in such a way that it is able to reproduce qualitative statements about uplift and rocking or tilting as a function of incisive model parameters and seismic excitation. The dissipation mechanisms of the model are presented and seismic tilting spectra are generated using different approaches. The suitability and applicability of these approaches for assessing uplift and rocking tendencies for large mobile equipment is reviewed using representative series of bucket wheel machines and stackers as examples. In addition, parameters are determined for quantitative application to further large mobile equipment and the delimitation criteria of qualitative and quantitative applicability are compiled. [ABSTRACT FROM AUTHOR]

Material properties of historical steels from exhibition hall 12 in Leipzig at elevated temperatures This paper describes material investigations on historic steel structures. In the course of the reconstruction of the exhibition hall 12 in Leipzig, parts of the original load‐bearing structure are to be restored and integrated into the new building. In order to verify the resistance of the structure, material tests were carried out on the steels and the riveted joints both under ambient temperature and at elevated temperatures. In analogy to the regulations of Eurocode 3, calculation values for the verification were derived from the test results. [ABSTRACT FROM AUTHOR]

Damage equivalence factors for deck slabs of steel railway bridges According to EN 1993‐2, the fatigue verification of railway bridges can be based on internal forces due to the standard load model 71. These internal forces are to be multiplied by a dynamic coefficient Φ2 and a damage equivalence factor λ. In this paper, factors λ1 allowing for the damage effect of traffic on quadrilaterally supported plates with torsionally flexible supports at the longitudinal edges as encountered in single‐track railway‐brides in a span range between 10.0 and 27.5 m are derived for three standard traffic situations. The required damage equivalence factors λ are obtained from the factors λ1, considering the annual traffic volume and the requested service life. [ABSTRACT FROM AUTHOR]

Dynamic train‐bridge compatibility: the reference method as a new form of verification Newly developed rail vehicles must be investigated regarding dynamic bridge compatibility before they are placed in service on the rail network of DB Netz AG. In this context, the dynamic effect on bridges from passing trains (train‐bridge interaction) is evaluated based on dynamic calculation results in the ultimate limit state (ULS) and in the serviceability limit state (SLS) and compared with calculated (previously static) minimum capacities of the infrastructure (resistance). In this paper, a new form of verification is presented. It makes it possible to extend the existing static capacities of the bridges by existing dynamic capacities, which usually allow higher permissible vehicle speeds in the railway network. For this purpose, computational results and database‐supported expert knowledge (fusion) from short‐ and long‐term monitoring of existing vehicles and their impact on the infrastructure are used to declare the bridge stock for these existing vehicles as operationally verified. On this basis, an applicable dynamic capacity for new vehicles can be formulated. The procedure is exemplarily shown for the ICE 3 (existing vehicle) and the new development of the BR 408 series (ICE 3neo). [ABSTRACT FROM AUTHOR]

Numerical investigations on the stability in the lower failure plane In this paper, three methods for verification the stability in the lower failure plane of an anchored retaining wall are compared: i) conventional methods of structural analysis (with different safety definitions), ii) finite element method with reduction of shear strength, iii) static and kinematic collapse theorem in finite element implementation. For the selected example of a retaining wall with one anchor, the two finite element methods investigated provide similar global safety factors as the methods of structural analysis with a safety definition according to design approach 2 of the Eurocode. With the safety definition according to Kranz, significantly higher safety factors follow. Both finite element methods can be used to determine utilization ratios in the sense of the Eurocode. These ratios are in the example shown are similar to the utilization ratios determined by means of design approach 2, but slightly more conservative. The investigations shown are a further indication that modern numerical methods can be used well in design. [ABSTRACT FROM AUTHOR]

The challenge of soil classification – Possibilities and advantages of the cone penetration test Geotechnical reports, which include the classification of the subsoil, represent the basis for project planning and are often essential for awarding construction services. Various standards, such as the ISO 14688‐1 and the Unified Soil Classification System (USCS), are used in practice to characterize the soil based on its particle size distribution and plasticity. In contrast, indirect classifications by means of cone penetration tests are based on soil behaviour type charts. In this paper, classification systems based on the physical properties of soils (ISO 14688‐1, USCS) and in‐situ tests are compared at different test and construction sites. The results indicate that soil behaviour type charts according to Robertson (2009, 2016) and Schneider et al. (2008) are suitable for estimating particle size distributions in alpine deposits, even though a better agreement is reached in fine‐grained soils with the USCS, compared to the ISO 14688‐1. Alternative classifications were elaborated for these soil behavior type charts, leading to an improved estimation of the particle size distribution. Further results illustrate that the estimation of particle size distribution by geotechnical engineers requires great experience in fine‐grained soils and can vary significantly. [ABSTRACT FROM AUTHOR]

Projects First tunnel boring machine goes into action at Brenner "Sill Gorge‐Pfons" / Andrehen der ersten Tunnelbohrmaschine am Brenner‐Baulos Sillschlucht‐Pfons Deutsche Bahn starts tunnelling for Wendlingen "big bend" / Deutsche Bahn startet Vortrieb für Große Wendlinger Kurve Renaturalisation of Lake Uri using tunnel spoil / Renaturierung des Urnersees mit Tunnelausbruchmaterial Contract awarded for H53 "Pfons‐Brenner" / Zuschlag für Baulos H53 Pfons‐Brenner erteilt Companies New estimate for total cost of the Brenner Base Tunnel / Neue Schätzung der Gesamtkosten für den Brenner Basistunnel Events 2nd European short course "Grouting Fundamentals & Current Practice" in Munich / Zweiter europäischer Short course "Grouting Fundamentals & Current Practice" in München Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

3DWelding – additive fabrication of structural steel elements This paper investigates the possibilities of robotic 3D printing with steel (WAAM – Wire and Arc Additive Manufacturing) in the construction industry. The aim of the project team is to develop a stable and economical manufacturing process for customized steel elements. Thus, the influence of different process parameters such as wire feed rate and travel speed on the weld shape and build‐up rate as well as on the material properties will be explained and a parameter window with stable, verified parameter sets will be defined for each material used. Three different filler metals (G 2Si1, G 3Si1, G 4Si1) are tested in terms of their strength and stiffness, with particular attention paid to the joining area between substrate and welded structure. For this purpose, test methods for testing additively manufactured components, especially for shear capacity, have been newly developed. As a proof of concept, an exemplary application is shown and the load‐bearing capacity of this connection is investigated in different configurations. [ABSTRACT FROM AUTHOR]

Unexpected fatigue cracks at main girders of a railway bridge – strain measurements under service and analyses based on fracture mechanics At a steel railway bridge, erected and taken into service in 1960, fatigue cracks were detected at some transverse stiffener to web connections at the lower flange of the main girder. These findings were surprising, because this specific connection detail was suggested in previous national design standards for fatigue. The paper presents the comprehensive strain measurements under service to show the local stress field at the critical detail within the web plate of the main girder, indicating the well‐known phenomenon of distortion‐induced fatigue, but with unexpectedly high resonance‐like bending stresses in the web. Based on fracture mechanics analyses, with implementation of the measured strain/stress data due to local and global effects at the transverse stiffener connection, as well as the measured material properties (fracture toughness and crack growth parameters) the remaining fatigue life was analysed. The positive results allow an unrestricted train operation in the future. It also turned out, that the mixed‐mode effects must be taken into account and considering only mode I at the crack tip may lead to unsafe results. [ABSTRACT FROM AUTHOR]

Manufacture and erection – TWIST The TWIST shell structure of the CUBE Result House was built from carbon concrete using the wet spraying method. The report from the executing company's perspective provides a detailed description of the technological realization based on the plans submitted for execution. The paper deals with special aspects of production, which result from technology, building materials used, building material properties and general conditions during construction. The experience gained should serve the further development of carbon concrete constructions and shows the need for development to be ready for practice with regard to construction. [ABSTRACT FROM AUTHOR]

Image‐based quality conctrol – part 1: consistency and paste content Today, only very simple empirical test methods are available for quality conctrol of fresh concrete on the construction site or in the production plant. Corrective actions in the case of quality deviations are based on a subjective visual inspection and thus on the experience of the inspector. The standard test method in Europe is the flow table test. The consistency of the concrete is derived from the diameter of the spread out fresh concrete. In order to overcome the deficiencies of this subjective fresh concrete testing, an image‐based method for determining (fresh) concrete properties was developed and validated. In addition to the diameter, extensive information can be derived from the surface properties of fresh conrete. In this paper, the image‐based determination of the consistency and the paste content is explained. The image‐based determination of granulometric properties (part 2) and the homogeneity of fresh concrete (part 3) will be presented in planned follow‐up articles. [ABSTRACT FROM AUTHOR]

A shear connector for direction‐independent shear force transmission in TCC slabs Currently used timber‐concrete composite (TCC) slabs carry loads only in one direction, and notches or other shear connectors are used for shear force transmission. As a result, these slabs lack the flexibility and effectiveness as a two‐way spanning, reinforced concrete flat slab. To overcome these limitations, a novel bi‐axial spanning TCC slab is being developed. The investigation of this new system is part of a research project, carried out at the University of Kaiserslautern (TUK) in collaboration with Werner Sobek Frankfurt GmbH & Co. KG (WS Frankfurt). The connection of the two cross‐sections is a key component in such systems. Therefore, developing a shear connector for direction‐independent shear force transmission is an important aspect of this project. In this paper, the results of numerical and experimental investigations of the connection system (cylindrical concrete notch) are presented and discussed. The focus is on the stiffness and load‐bearing capability as well as the structural behaviour. [ABSTRACT FROM AUTHOR]

Rods glued into cross laminated timber – experiments, numerical simulation and load capacity prediction Timber construction is currently pushing new boundaries in terms of dimensions and architectural possibilities, as shown by the increasing number of high‐rise buildings. This is made possible by high‐performance connections, such as glued‐in rods (GiR, with rods made of steel and fibre reinforced polymers), and wood materials, such as cross‐laminated timber (CLT), which consists of several layers of boards glued flat and crosswise to each other, or glued‐laminated timber (GLT) where all layers are glued together in the same orientation. This paper highlights the current state of the art of GiR glued into CLT and gives an overview of recent experimental and numerical results. The similarities, but also the differences, between GiR glued into CLT and GLT, which result from the different orientation of the individual layers, are shown. Another focus is on the prediction of the connection load‐carrying capacity, for which only very few approaches are currently available. [ABSTRACT FROM AUTHOR]

Prognostic determination of life cycle rate of return with BIM The value retention of real estate is increasingly ensured by the inclusion of sustainability aspects in the planning. As a result, life‐cycle considerations of the future earnings situation of a property are already necessary in the project development phase. By comparing the revenues to the life cycle costs, the life cycle return (LCR), as it is called by the authors, can be determined as a prognostic parameter for assessing the profitability of an investment. In this paper, the project information available at an early stage is integrated into a digital building model to determine the LZR. Building Information Modeling (BIM) can reduce the uncertainty of the cost calculation in an early project phase by linking the digital planning status with relevant building information. Based on a digital building model, it is thus possible to determine the LZR in a way that is comprehensible and adaptable to planning variants. The breakdown of all revenues and costs relevant for the life cycle is necessary for this. Changes and additions to the building model require a continuous and rapid adjustment of the calculations to the respective planning status. This makes it possible to continuously check the initial parameters defined at the beginning of the project. [ABSTRACT FROM AUTHOR]

Projects First tunnel boring machine in Brenner contract section H61 reaches destination / Erste Tunnelbohrmaschine im Brenner‐Baulos H61 am Ziel Breakthrough at Sarnersee / Durchbruch am Sarnersee Tunnel construction for the Brenner Base Tunnel North feeder / Stollenbau für den Nordzulauf zum Brenner Basistunnel beauftragt A13 Ceremony to mark start of work on the Isla Bella Tunnel / A13 Anschlagfeier Sicherheitsstollen Tunnel Isla Bella Implenia wins subway projects in Toulouse and Oslo / Implenia erhält U‐Bahnprojekte in Toulouse und Oslo Preparations for machine tunnelling in Construction Lot H41 of the Brenner Base Tunnel / Vorbereitungen für den maschinellen Vortrieb im Baulos H41 des Brenner Basistunnels Tunnel refurbishment for the Lahn Valley Railway / Tunnelsanierung für Lahntalbahn Restoration of the land to its natural state in the Eisack underpass construction lot / Renaturierungsmaßnahmen im Baulos Eisackunterquerung Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

In the construction industry, increased efforts are being made to automate production processes using industrial robots in order to increase efficiency, improve quality and optimize the use of materials. Tunnel construction is particularly suitable for the use of modern production methods, as the increased use of machines and the high repetition factor of the components used make it possible to scale production technology across project boundaries. This paper provides examples of current developments in segment production, in particular the use of industrial robots in the prefabrication of reinforcement cages and subsequent concreting. Necessary adaptations in segment design are pointed out when welded reinforcement is used, and conceivable further developments are shown. The medium‐term goal is a continuous IT‐based production control system that allows short‐term adjustments to segment production, logistics and subsequent installation in the tunnel. [ABSTRACT FROM AUTHOR]

Shape optimisation of eccentrically loaded columns – theory and experimental verification. In shape optimisation, the external shape of the structural component is adapted to the predominant force flow. In this way, large load increases can be achieved with the same material use, or high material savings can be achieved with the same load‐bearing capacity. In this paper, a shape optimisation for eccentrically loaded columns is presented, where the bending stress results from a frame effect of the load‐bearing system. This is the case, for example, in edge columns of typical reinforced concrete skeleton structures, as they are usually used in residential and commercial buildings. The shape optimisation method presented in the article can be applied to columns with an arbitrary ratio of a moment‐normal force loading, provided that a material failure occurs. Results for shape optimisation in the case of a stability failure have already been published separately for centrically pressed columns. The optimisation itself is carried out iteratively on a column segmented over the height under the criterion of achieving a uniform stress state in the component. With the help of an experimental check on 3.3 m high columns, the selected calculation and optimisation method could be verified. In addition to the failure loads, the concrete strains and the deformation behaviour were also analysed and evaluated at selected points of the specimen. [ABSTRACT FROM AUTHOR]

Punching shear in irregular flat slab systems – Recommendations for modeling and design The punching shear verification is often the decisive verification in design due to the concentrated load introduction. Moreover, uneven shear stress distributions often occur in the punching shear area as result of irregular flat slab systems or eccentric loads. In structural design it is often questionable, how a non‐uniform shear stress distribution can be considered with acceptable effort. The direct determination of the shear stress distribution along the control perimeters using FE methods is not explicitly excluded in the current Eurocode 2 but is also not described in more detail. This gives considerable freedom in design for the structural engineer, but also ambiguities for interpreting the results. In this paper, FE approaches for determining the factor β or for directly considering the non‐uniform shear stress distribution are presented and analyzed based on an application example. Finally, recommendations and modelling advice are given for the pragmatic and, as far as possible, realistic determination of factor β for consideration of unbalanced moments. [ABSTRACT FROM AUTHOR]

Universal high‐performance columns made of high‐strength steels without welding In recent years, steel‐concrete composite columns made of normal‐strength steels are seldom used owing to the economic and technological advantages of precast reinforced concrete columns. Though, the use of high‐strength structural steels bears high potential for the efficient production of composite columns with excellent structural performance that are economically competitive to precast concrete columns, there are currently major obstacles to use of the ultra‐high‐strength steels (UHSS) in Germany. Hollow section composite columns with embedded high strength steel core without welded connections provide an opportunity to regain lost market share. A research project, funded by the AiF (Arbeitsgemeinschaft industrieller Forschungsvereinigungen), is intended to explore the potential of UHSS composite columns by experimental and theoretical investigations. The present paper demonstrates the concept of such composite columns with UHSS and gives first exciting insights into the research results. In addition to column tests under ambient and fire conditions, small scale tests are necessary to investigate various influencing factors and to create the basis for new and easy to use design and construction principles that allow efficient application. [ABSTRACT FROM AUTHOR]

Mechanical material behaviour of ultra‐high‐strength structural steel S960QL in case of fire Due to their good strength‐to‐weight ratio, high‐ and ultra‐high‐strength structural steels are increasingly used in multi‐storey and industrial buildings in the form of plate material, pipes and sections. For structures with fire protection requirements, however, the use of high‐strength structural steels is currently inhibited by a lack of knowledge regarding temperature‐ and rate‐dependent material behaviour. Comprehensive knowledge of the material behaviour is a basis for a realistic modeling of the load‐bearing behaviour of steel structures. Within the framework of the FOSTA‐research project P 1502, systematic investigations of the structural material behaviour of ultra‐high‐strength steels are carried out in terms of an extensive tensile test program. The aim of the project is to characterise the mechanical material behaviour during all phases of a fire, including the cooling phase of natural fire scenarios. The paper addresses the material behaviour of quenched and tempered steel S960QL in fire. Steady state and transient state tensile test results are presented and used for the characterisation of the material behaviour during the heating phase of a fire and the comparison to common material models. In addition, the results of natural fire tests for the evaluation of the material behaviour in the cooling phase and the residual behaviour are presented. [ABSTRACT FROM AUTHOR]

Transverse sliding of the 985 m long steel Lennetal bridge The Lennetal bridge is one of the major viaducts on the A45. Due to the increased traffic volume and the structural condition of the existing bridge, it was necessary to build a new bridge. In order to restrict traffic as little as possible during the construction period, the new superstructure was built for one direction of traffic in a lateral position and then moved to its final position by means of a transverse sliding. With a length of almost 1000 m, the Lennetal bridge is – in relation to the bridge length – the largest transverse sliding that has been realised in Germany so far. This paper deals with the special features of the planning and execution of the transverse sliding. [ABSTRACT FROM AUTHOR]

Digital education for geotechnical engineering: current status and further developments Digital teaching tools and materials have been used at universities (of applied sciences) for several years and open up new ways for higher education. However, depending on the type and intended quality, the creation of these teaching materials can be very time‐consuming and mean a lot of extra work for teachers. In a collaborative project to produce teaching videos for geotechnical field and laboratory experiments, the authors of this paper have experienced that a collaborative approach across university borders for the production of teaching materials has many advantages. Inspired by this collaboration, the authors of this report conducted a survey among German‐speaking geotechnical engineering chairs at (technical) universities and universities of applied sciences. After three semesters of mostly digital or hybrid teaching due to the Corona pandemic, one aim of this survey was to capture the use of digital teaching materials in the field of geotechnical engineering. Another goal was to initiate a network in which geotechnical engineering professors can exchange information on teaching topics and jointly create and use (digital) teaching materials. This article presents the authorś collaborative teaching project and the results of the survey conducted. Moreover, it reports on the first activities of the new network. [ABSTRACT FROM AUTHOR]

Validation of the AVISA model Despite advanced design technologies, construction on cohesive soils is still a challenge. Especially when dealing with cyclic loading conditions combined with the time‐dependent behavior of cohesive soils, such as offshore structures or even dams, the tools to predict the long‐term deformations of fine‐grained soil are limited. Due to the complex influence of loading rate, preloading, and soil structure, it is necessary to understand the effects of these influences on cohesive materials through laboratory testing and describe them numerically through accurate and physically based constitutive equations. Researchers (continue to) develop many hundreds of material models each year. Most of them are used for PhDs and not investigated further. In this work, such a model, developed in the first author's PhD, is be validated. The performance of the AVISA model has been previously demonstrated on experiments of various fine‐grained soils. In this paper, a new experimental study on Malaysia Kaolin is used for the validation of the model. Furthermore, the reproducibility of the so‐called Krey and Tiedemann criteria, parameters φ′s , c′ und φ′ is investigated by simulations of simple shear tests. It should be noted that many constitutive models for fine‐grained soils fail in this task. [ABSTRACT FROM AUTHOR]

Projects Final major tunnelling contract awarded for Sydney Metro West / Letzter großer Tunnelbauauftrag für Sydney Metro West vergeben Implenia builds Boknafjord tunnel in Norway / Implenia baut Boknafjord‐Tunnel in Norwegen Contracts for main tunnel and materials management for second tube of Gotthard road tunnel / Verträge über Haupttunnel und Materialbewirtschaftung für zweite Röhre Gotthard Straßentunnel Greywacke – Rock of the Year 2023 / Grauwacke – Gestein des Jahres 2023 Carcassing work in the Albula Tunnel complete / Roharbeiten im Albulatunnel abgeschlossen Second tube of Long Itchington Wood Tunnel launched / Zweite Röhre der Long Itchington Wood Tunnels angefahren Shell construction of cross passages in Rastatt Tunnel complete / Querschläge im Tunnel Rastatt im Rohbau fertig Blast driving in Cholfirst safety tunnel started / Sprengvortrieb im Sicherheitsstollen Cholfirst gestartet North Portal of Brenner Base Tunnel is taking shape / Nordportal des Brenner‐Basistunnels nimmt Gestalt an New Wendlingen‐Ulm line goes into operation / Neubaustrecke Wendlingen‐Ulm in Betrieb Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Glacial soil deposits are present in Europe on both sides of the Alps, in Scandinavia, Northern Germany, Poland and in North America. There are typical names of the stages of the glaciation, however, the geotechnical characteristics of glacial deposits are similar in all regions; but are very heterogeneous locally. Glacial deposits extend from boulders to invisible silt particle (rock flour) and to clay particles, both of similar grain size. In this paper the focus will be on clean gravel without fines, so‐called open gravel and the challenges and solutions for tunnelling. Face support by pure bentonite slurry is insufficient in open gravel. Different techniques have been used in practice: clogging the pore channels with fines of appropriate gradation by controlling the content fines in the slurry. Use of high viscous slurry with increased clay or bentonite content. In another solution lime powder and polymers were added in the excavation chamber of an earth‐pressure shield to modify the ground. Other aspects such as muck disposal will be evaluated. [ABSTRACT FROM AUTHOR]

Failure criteria for foam‐grouted gravel under multiaxial loading Foam grouting is an innovative method for improving the mechanical properties of cohesionless, coarse‐grained soils. Despite this, only a few experimental studies have been conducted to assess the failure of foam‐injected soils under multiaxial loading. This paper aims to fill this gap in knowledge. The stiffness and strength of the natural soil, which serve as reference values for the evaluation of the improvement effect due to the injection, are derived from drained triaxial tests. The mechanical behaviour of the foam‐injected soil is investigated using uniaxial, triaxial, and splitting tensile tests. The foam‐injected soil, exhibits significantly higher strength and stiffness but lower ductility than the untreated soil. The ductility of the foam‐injected soil increases with increasing lateral pressure. The splitting tensile strength is only a small fraction of the compressive strength. The adequacy of the failure criteria Mohr‐Coulomb, Hoek‐Brown and Lade for the description of the failure of foam‐injected coarse‐grained soils is verified. All three failure criteria are basically suitable to describe the state of failure in triaxial compression. For compressive and tensile loading, the Hoek‐Brown and Lade failure criteria seem to be more appropriate compared to Mohr‐Coulomb. [ABSTRACT FROM AUTHOR]

Projects First TBMs launch in London for HS2 project / Erste TBMs in London für das HS2‐Projekt gestartet Breakthrough in the Kerenzerberg tunnel / Durchschlag im Kerenzerbergtunnel The Inn district power station has been put into operation / Gemeinschaftskraftwerk Inn in Betrieb genommen New schedule and cost plan for 2nd Munich main line / Neuer Zeit‐ und Kostenplan für 2. Stammstrecke München Contract awarded for the Wendlingen Tunnel on the new Stuttgart–Ulm railway line / Tunnel Wendlingen auf der Neubaustrecke Stuttgart‐Ulm vergeben All tunnelling work in the Stuttgart basin has been completed / Alle Tunnelvortriebe im Stuttgarter Talkessel beendet Sustainable pilot project in the Filder Tunnel uses cement‐free building materials / Nachhaltiges Pilotprojekt im Fildertunnel setzt auf zementfreie Baustoffe Herrenknecht AG wins bauma innovation award 2022 / Herrenknecht AG gewinnt bauma Innovationspreis 2022 Events Award ceremony for the international Mining the Future competition / Preisverleihung für den internationale Wettbewerb Mining the Future People Obituary Dipl.‐Ing Guntram Innerhofer / Nachruf Dipl.‐Ing Guntram Innerhofer Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Various methods have been developed in recent decades to predict hazards associated with karst voids in underground construction. Common to all these methods is that the predicted range of water inflow is often insufficient for the purpose of implementing the planned construction works. This is usually due to an incomplete knowledge of the karst conduit system within a project area, making it difficult to predict the position and characteristics of karst voids. The method presented in this paper permits a robust prediction of karst water inflow. It is based on a combination of stochastically generated, pseudo‐genetic karst conduit systems and hydraulic modelling of the hydrogeological conditions using a Monte Carlo approach. This approach facilitates a plausible estimation of the expected range of karst‐induced water inflows and also enables the probability of encountering a karst voids. to be determined. The predictions allow for differentiated treatment of the hazards associated with karst water during the construction and operation phase of underground structures. In concrete terms, this relates to the planning and implementation of exploratory measures and ground‐improvement measures, the design of the dewatering system and its monitoring during the construction and operation phase. [ABSTRACT FROM AUTHOR]

Projects Tunnelling work for the Obervellach II power station has been completed / Vortriebsarbeiten für Kraftwerk Obervellach II abgeschlossen Refurbished Bosruck tunnel is fit for the future / Sanierter Bosrucktunnel ist fit für die Zukunft Opening of the refurbished Belchen tunnel / Eröffnung des Sanierungstunnels Belchen Start of tunnelling for the BBT H41 "Sill Gorge – Pfons" contract section / Tunnelanschlag im BBT‐Baulos H41 Sillschlucht‐Pfons Tunnel boring machine started in Göschenen / Tunnelbohrmaschine in Göschenen gestartet Manufacturing of test element for the Fehmarnbelt Tunnel successfully completed / Erfolgreiche Fertigung eines Testelements für den Fehmarnbelt‐Tunnel Pilot project for renewal of the Elleringhausen Tunnel / Pilotprojekt zur Erneuerung des Elleringhausener Tunnels Construction of Hamburg's district heating tunnel gets underway / Baustart für Hamburgs Fernwärmetunnel Deutsche Bahn submits planning for Offenburg Tunnel ‐ Deutsche Bahn reicht Planung für Tunnel Offenburg ein Entire route of the new section of the Brenner North feeder now established / Gesamtverlauf der Neubaustrecke Brenner‐Nordzulauf steht fest Contract awarded for Gotthard main northern section / Gotthard Hauptbaulos Nord vergeben Call for papers – Topics for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

Great importance is attached to 'pressure‐volume records' for the execution, documentation and billing of rock grouting. In this context, special digital data management systems are now available which can provide data in a structured and consistent format that is also suitable for artificial intelligence (AI) approaches. Using datasets from a tunnel project in Scandinavia, this paper shows that artificial neural networks can be used to reliably predict the evolution of pressure‐volume records or the volume of grout injected at the end in the interests of construction site efficiency. Taking into account the technical feasibility of using AI to support tunnel grouting, we then show which contractual modifications would be required in order to make effective use of corresponding developments. [ABSTRACT FROM AUTHOR]

The Rudolf‐Fettweis hydropower plant, owned and operated by EnBW Energie Baden‐Württemberg AG, is situated in the Murg valley in the Northern Black Forest. The construction of a new underground Lower Basin is planned to upgrade the existing hydropower station. The in‐situ rock mass consists of Forbach Granite with local weakness zones, as encountered in the boreholes. Considering the extent of the project area, a 3D geological prediction model was used to allow a better interpretation of the spatial relationships of weakness zones in the rock mass and to optimize the orientation of the underground caverns. Adverse effects for the public were counteracted at a very early stage, so that the project received a high level of public acceptance. The present paper describes the current state of the project. [ABSTRACT FROM AUTHOR]

Slow moving landslides are a common phenomenon in the Alps. Often built‐up areas, infrastructure such as motorways, water storage or stream control structures are affected by such landslides. In this paper two case studies are discussed to present a decision‐making system for the evaluation and handling of such slow‐moving landslides. [ABSTRACT FROM AUTHOR]

Zur Bemessung einer Einschnittsböschung in rutschgefährdeten Schichten des Oberen Buntsandsteins (Röt) im Grenzbereich zum überlagernden Unteren Muschelkalk wurden Labor‐ und Feldversuche zur Bestimmung der Scherfestigkeit in den kritischen Schichthorizonten durchgeführt. Die direkten Scherversuche im Feld bilden den typischen Grenzzustand des Gleitens auf prädestinierten Verwitterungshorizonten weit besser ab, als dreiaxiale Druckversuche an ungestörten Proben des geschichteten Gebirges. Die mit beiden Versuchsarten ermittelten Scherfestigkeiten sind als Grundlage für eine Langzeitbemessung abzumindern, da durch die Entlastung beim Auffahren des Einschnitts und durch den fortschreitenden Verwitterungsprozess der dominante Anteil der Kohäsion an der Scherfestigkeit stark abfällt. Der Beitrag beschreibt die spezifischen geologischen Standortbedingungen sowie die Durchführung und Auswertung sowohl der In‐situ‐Scherversuche als auch der Triaxialversuche. Im Ergebnis werden angemessene Werte der Langzeitscherfestigkeit abgeleitet. In situ‐determination of the effective shear strength of landslide‐prone layers of the Upper Red Sandstone. The paper describes how the common limit state design of a rock slope can be reliable improved when the necessary strength parameter values are determined by field tests. For the design of a down cutting in slide prone layers of red sandstone in the transitional zone of the overlying shell limestone, laboratory and field tests were implemented in order to determine the shear strength within the critical range. The typical limit state for sliding on predestinated weathered layers deliver far better results with direct in situ shear tests, than with triaxial test on undisturbed samples of rock. The basis for a long term design are the shear strength determined with both test types, which has to be reduced, as the amount of the cohesion as part of the resistance might be reduced due to the reload during excavation and the progressive weathering process. The specific geological site conditions as well as the implementation and evaluation of the in situ shear tests and the triaxial tests are presented in the paper. As a result, appropriate values for the long term shear strength are proposed. [ABSTRACT FROM AUTHOR]