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Handling geotechnical peculiarities in specialized ground models – an experience report Dr. Spang GmbH has developed numerous specialized ground models in recent years and has gained corresponding experience in ground modeling. Within the company, a standard procedure for creating these specialized models has been established. From a software perspective, automatic meshing (triangulated 3D surface mesh of the layer boundaries) already delivers useful results for many standard cases. However, in geotechnics, there are not only standard cases and features to assess. Geotechnical peculiarities (e. g. inhomogeneous layering) result in an increased manual modeling effort. This article aims to shed light on how to handle these peculiarities in modeling, present the additional modeling steps involved, and highlight the software limitations that arise in automatic meshing (interpolation or triangulation) in such special cases. [ABSTRACT FROM AUTHOR]

Summary Artificial Intelligence (AI) holds great potential in leveraging complex relationships within large datasets. The primary challenge lies in identifying relevant features in abstract data such as molecules, compounds or spectra. Models are trained and tested using supervised or unsupervised learning methods. Active learning and iterative processes enhance accuracy. AI offers the potential for precise predictions and innovation in both research and industry. [ABSTRACT FROM AUTHOR]

Copyright of Automatisierungstechnik is the property of De Gruyter 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 e & i Elektrotechnik und Informationstechnik is the property of Springer Nature 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 e & i Elektrotechnik und Informationstechnik is the property of Springer Nature 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 Automatisierungstechnik is the property of De Gruyter 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.)

Many real-world situations are characterized by complexity. This article focuses on the transformation of corresponding complex, nutrition-associated phenomena from the real world into adequate educational content. As an introduction, the underlying concept of complexity and the nutritional-ecological modeling technique are presented. Based on this, potentials of qualitative modeling for didactic structuring are explored. [ABSTRACT FROM AUTHOR]

In fuel‐bearing components, particularly in automotive applications operating at elevated temperatures, the durability of light metals is significantly influenced by their susceptibility to alkoxide corrosion. Alkoxide corrosion is characterized by its spontaneous nature and exceptionally rapid degradation of materials once initiated. This study presents an innovative high‐pressure and high‐temperature micro‐reactor, which enables precise measurements with superior sensitivity for determining the exact initiation times and reaction rates of pitting corrosion. Exemplified tests of surface roughness and water content effect on pitting initiation times were conducted and data was generated for a numerical phase field model to demonstrate the reactor capabilities. Experimental findings suggest that impurities present on both the material surface and in the fuel exhibit a significant influence on corrosivity, thereby affecting the reliability of the components. Moreover, the experimental data points have been utilized to extract the corrosion kinetics and calibrate the numerical model. The initial findings successfully demonstrate the ability to replicate corrosion kinetics and accurately represent pit morphologies and estimate reaction‐related parameters in a predictive manner. [ABSTRACT FROM AUTHOR]

A template‐assisted synthesis was used to synthesize porous carbon scaffolds with silica gel as a template via chemical vapor infiltration (CVI). The process was mathematically modeled and simulated by varying different reaction parameters to optimize the carbon deposition. The experimental results could be reproduced well with the models. The additional description of the laminar flow significantly improves the simulation. [ABSTRACT FROM AUTHOR]

Copyright of Automatisierungstechnik is the property of De Gruyter 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 Synthesis Philosophica is the property of Croatian Philosophical Society 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.)

Increase of technical lifetime of infrastructures based on semi‐probabilistic considerations One of the most important measures in the discussion on improved sustainability in construction is to extend the service life of our structures [1]. Therefore, intensive research is conducted with regard to changing environmental conditions as well as external load effects for structures and new materials and their impact on the production and operation of infrastructures. Already now, according to [2], changes in the kinematics of the degradation mechanisms can be observed. In particular, changing environmental conditions (exposures) can accelerate but also slow down the degradation of materials and structures. These understandings of the degradation processes, but also the improved knowledge of the geometry and effective mechanical building material properties, should be effectively transferred into engineering practice for the assessment of structural reliability and remaining service life [3]. This paper presents how the elements of reliability analysis can be combined with the elements of in‐depth testing and monitoring procedures to periodically evaluate the degradation processes due to changing environmental conditions and new building materials. Subsequently, the remaining service life can be continuously updated with the help of semi‐probabilistic partial safety considerations. [ABSTRACT FROM AUTHOR]

Copyright of Automatisierungstechnik is the property of De Gruyter 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.)

Influence of transverse tensile loads on the compressive strength of carbon reinforced concrete Initial findings on the load‐bearing behaviour of carbon reinforced concrete components under uniaxial compressive stress are available, however multi‐axial stress states are of particular relevance for an application in construction practice. It is known from steel reinforced concrete constructions that transverse tensile stresses lead to a reduction in the compressive strength, although there is still no international agreement on the actual reduction. In this paper we investigate the boundary conditions under which carbon reinforced disc shaped specimens can be tested under combined compressive and tensile loading. This includes the anchoring of the carbon yarns required for the tests in limited space conditions as well as the influence of the loading regime – proportional or sequential – and the manufacturing process – laminated or casted – on the test results. Finally, an outlook on the following investigations is given. [ABSTRACT FROM AUTHOR]

New perspectives on the load bearing behavior of RC‐structures without shear reinforcement The shear behavior of structural members has been an integral part of research in concrete structures for more than 100 years. In recent years, various mechanical shear models have been developed that deliver important insights into the background of shear behavior and are able to provide physical explanations for shear failure in RC members without shear reinforcement. However, these models require further experimental validation. New measurement techniques (e.g. digital image correlation or fiber‐optic strain measurement) play a decisive role in this context, allowing deeper insights into the load‐bearing behavior of reinforced concrete components subjected to shear loads. Based on experimental investigations with modern measurement techniques, software has been developed that performs an automated crack detection based on the finite element method with detailed evaluation of the kinematics and the stresses transferred in the crack. In this paper an overview of different evaluation methods of experimental investigations with modern measurement techniques is given, on the basis of which an in‐depth evaluation of new model approaches can be carried out. [ABSTRACT FROM AUTHOR]

Several heat treatment procedures are designed considering critical temperatures of phase transformation evaluated through dilatometric testing of 20MnMoNi55 steel to transform low carbon bainitic as‐received material into ferrite‐martensite dual‐phase steels consisting of varied martensite fractions. A thorough metallographic study correlated with the micro‐hardness of constituent phases ensures morphological characteristics along with its fractional variations in as‐received and dual‐phase steels. The impact of fractional variation in constituent phases on the uniaxial monotonic deformation characteristics of dual‐phase steels has been observed with a correlation study between experimental tensile and finite element simulated results. Therefore, a physical‐based model with a 2‐dimensional representative volume element has been established, addressing actual morphological characteristics obtained from metallographic studies. Moreover, the constitutive flow behaviours of ferrite and martensite are also derived from the dislocation‐based hardening model to address the actual deformation phenomenon. Finally, an inhomogeneous deformation behaviour among constituent phases and localization of plastic strain in ferrite matrix has been observed with von‐Mises stress, and equivalent plastic strain distribution through finite element simulated results. This phenomenon is again confirmed with kernel average misorientation mapping and geometrically necessary dislocation density evaluation through electron backscattered diffraction of tensile samples subjected to different degrees of plastic strain. [ABSTRACT FROM AUTHOR]

Bond Behaviour between GRP Reinforcing Bars and High Performance Aerogel Concrete The bond behavior between reinforcing bars and concrete has a significant influence on the overall load‐bearing behavior as well as the serviceability of reinforced concrete components. Extensive investigations have been carried out in the past for glass fiber reinforced plastics (GRP) in connection with normal concrete (NC). It has been shown that the bond behavior of GRP reinforcement is significantly determined both by the surrounding concrete and by the product‐specific properties (geometry, materials) of the reinforcement bars. For the production of reinforced components made of high‐performance aerogel concrete (HPAC), for which GRP reinforcement elements should preferably be used due to their low thermal conductivity, no studies have been carried out yet. Since it is not possible to simply extrapolate the bond behavior of GRP reinforcement with normal concrete to other types of concrete, 48 pull‐out tests were carried out in the investigations presented below to determine the bond behavior. For comparison with the results from the current state of research, the bond behavior of GRP reinforcement in NC was also determined by means of 24 additional pull‐out tests. Based on the results, analytical bond stress‐slip models were derived for both HPAC and NC. Subsequently, these bond stress‐slip relationships were integrated into a FE model and compared with the results of the experimental investigations. [ABSTRACT FROM AUTHOR]

Torsional structural behavior of hollow concrete cross‐sections in closed and gaping segment joints – Part 3: Verification Precast concrete elements for segmented towers of wind turbines are series products that must be designed to be as resource‐efficient as possible in terms of sustainability. In this context, the shear force and torsion load‐bearing capacity of the joints are of great importance in the design of the precast concrete towers. In parts 1 and 2 of this publication series, a new calculation model for the joint load‐bearing capacity was presented, which is verified in the present 3rd part on the basis of test results and FE calculations. In addition, a comparison to other models is made and the application areas of the models are narrowed down. [ABSTRACT FROM AUTHOR]

Graded Concrete (2. Generation) – The Combination of Hollow‐Core Construction with Trajectory‐Based Reinforcement With the exception of the so‐called shear stirrups, the reinforcement layout in reinforced concrete components usually follows the geometry of the components, i.e. the reinforcement is either laid parallel to the bounding surfaces or, more rarely, perpendicular to them. Although it is known that this type of reinforcement layout leads to significant additional consumption of reinforcing steel, it is still considered the global standard today. This is justified by the simplicity of laying the reinforcement, the possible lower error rate on the construction site and the savings in labour costs that can be achieved through both. Due to the worldwide need to reduce resource consumption, energy consumption and climate‐damaging emissions, especially in the production of buildings, it can be assumed that the amount of reinforcement installed per component will decrease in the future. For the aforementioned reasons, the quantities of concrete used per component will also decrease. In addition to a stronger structuring of the component surfaces, cavities within the components as well as the use of different concrete grades within a component will increasingly be used. In this article, a technology is presented with which significant material savings can be achieved in reinforced concrete construction. It consists of a hollow body construction method in combination with a load path‐oriented reinforcement. This technology allows the implementation of weight‐minimised, material‐efficient, emission‐reduced and separable reinforced concrete components. [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]

Configuration, structural design and planning of the TWIST carbon reinforced concrete shells The carbon reinforced concrete house CUBE was built exclusively with non‐metallic reinforcement, primarily from carbon fibres, to show its potential to the realisation of slim, concrete‐minimised buildings. This article presents the structure of the striking, curved carbon reinforced concrete shells TWIST, which rotate from the vertical to the horizontal, the load transfer of the building and the basics for the cross‐sectional design of the concrete elements and the supporting structural steel components. In addition, the procedure of the structural engineers in the detailed planning phase is shown, including the software products used. [ABSTRACT FROM AUTHOR]

Optimized concepts for the deconstruction of natural draught cooling towers by blasting The deconstruction of natural draught cooling towers represents an essential part in the course of the conversion of old power plant sites. For monetary reasons in combination with reasons of sustainability, which are particularly reflected in the reusability of the site area and the recycling of the resource reinforced concrete, an immediate deconstruction of the natural draught cooling towers after the end of operation is recommended in most cases. In addition to the established state of the art, the article shows potentials for the further development of concepts for the deconstruction of natural draught cooling towers by blasting. Complex numerical simulations nowadays offer the possibility of precise simulations of both the structural stability for temporary, weakened construction stages and the collapse behaviour of reinforced concrete structures in the event of blasting. The key aspect is safety in various facets, which must also be considered and guaranteed for adjacent buildings in the immediate neighbourhood in particular. The new deconstruction concepts presented, for which no practical experience is available at this time, are compared with the established concepts with regard to the aspects of structural stability, collapse safety, vibration prognosis, necessary safety measures, effects on the environment, workload and costs. [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]

Copyright of Scientific Journal of Polonia University is the property of Polonia University of Czestochowa 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.)