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Copyright of Beton- Und Stahlbetonbau 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.)

Determination of the maximum shear capacity of reinforced concrete (RC) beams and slabs has been a challenging task for over 100 years. Recently, the shear crack propagation theory (SCPT) was developed as a unified mechanics-based solution to determine the ultimate capacity and to explain the phenomenon of one-way shear in RC members without shear reinforcement. The proposed theory is not limited to steel-RC members and can be applied to members with nonmetallic reinforcement accounting for their material parameters and constitutive relationships. Further, the SCPT does not focus only on the ultimate state but also on the behavior during the entire loading process up to failure. In this paper, the application of the SCPT is extended to RC members with longitudinal fiber-reinforced polymer (FRP) reinforcement without stirrups for the first time. A parametric study is first presented to explore the effect of FRP bar properties on shear behavior and shear transfer mechanisms in RC beams. Subsequently, the experimental results of 44 beam tests reported in the literature are used for validation. The results showed that the SCPT provided accurate estimates of the shear strength of FRP-RC beams that compared favorably with those from current design codes. [ABSTRACT FROM AUTHOR]

Summary: Background: To prevent complications of paediatric ulcerative colitis (UC), it is critical to understand their predictors. The Paediatric Inflammatory Bowel Disease Ahead (PIBD Ahead) program identified the relevant outcomes and their potential predictors. However, external validation of these results in larger cohorts is required. Aims: The aim of this study is to investigate these outcomes and their predictors. Methods: We included 743 patients aged under 18 years with UC from the multicentre German‐Austrian CEDATA‐GPGE registry. We performed Cox regressions, Kaplan–Meier estimator, and receiver operating characteristics curve analyses to analyse predictors of poor outcomes. Results: Older age at diagnosis was associated with relapse, hospitalisation, the use of immunomodulators, use of biologics, and therapy escalation. Higher disease activity, as in acute severe colitis in the first 3 months, was significantly associated with further acute severe colitis and the need for biologics. Upper gastrointestinal tract involvement was a risk factor for the need of intravenous corticosteroids and biologics. A faecal calprotectin of >685 μg/g was associated with a higher risk of subsequent acute severe colitis with a sensitivity of 79.0% and a specificity of 59.1%. A lower haematocrit at diagnosis was predictive of the use of biologics. Colectomy was rare. Conclusions: This study validates predictors of poor outcomes in paediatric patients with UC. Our results might help physicians to anticipate poor outcomes and initiate appropriate treatment strategies at an early stage. [ABSTRACT FROM AUTHOR]

Despite of intensive research on concrete fatigue, the transfer of fatigue characteristics determined at the material level to the structural level remains a challenging issue. In this paper, the propagation of fatigue‐induced damage through the concrete structure is analyzed using a microplane fatigue model for concrete recently developed by the authors. To this end, our recent experimental study in which the fatigue propagation was monitored at the structural level represented by prestressed concrete beams is used to derive a general interpretation of the stress redistribution process using of the developed model. The numerical studies show that the developed microplane fatigue model provides a powerful computational tool for in‐depth analysis of the correspondence between the fatigue behavior at the material and structural scales in a wide range of load configurations. In addition, the thermodynamically based constitutive model allows for the quantification of the energy dissipation during the process, revealing the possibility of deriving material‐specific energetic characteristics that can further help to make the predictions of fatigue life more accurate. Highlights: Structural experiments validate the constitutive fatigue hypothesis.Damage‐induced energy dissipation is an objective value for fatigue characterization.Insights into the fatigue life extension of concrete at the structural level are provided.Structural stress redistribution induces variable load amplitudes at local level. [ABSTRACT FROM AUTHOR]

Background: Abdominal pain is a common and often debilitating issue for children and adolescents. In many cases, it is not caused by a specific somatic condition but rather emerges from a complex interplay of bio-psycho-social factors, leading to functional abdominal pain (FAP). Given the complex nature of FAP, understanding its origins and how to effectively manage this condition is crucial. Until now, however, no questionnaire exists that targets knowledge in this specific domain. To address this, the Abdominal Pain Knowledge Questionnaire (A-PKQ) was developed. Methods: Two versions were created (one for children and one for parents) and tested in four gastroenterology clinics and one specialized pain clinic in Germany between November 2021 and February 2024. Children between 8 and 17 years of age (N = 128) and their accompanying parents (N = 131) participated in the study. Rasch analysis was used to test the performance of both versions of the questionnaire. Results: The original questionnaires exhibited good model and item fit. Subsequently, both questionnaires were refined to improve usability, resulting in final versions containing 10 items each. These final versions also demonstrated good model and item fit, with items assessing a variety of relevant domains. Conclusion: The A-PKQ is an important contribution to improving assessment in clinical trials focused on pediatric functional abdominal pain. [ABSTRACT FROM AUTHOR]

Copyright of Beton- Und Stahlbetonbau 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.)

To reduce resource consumption and the carbon footprint of the construction industry, new construction principles that stipulate the minimisation of materials are urgently needed. Floor slabs show high potential for saving materials and CO2 emissions, as they account for around 50% of the total volume of concrete used worldwide. A promising approach is the use of corrosion-resistant carbon fibre-reinforced polymer (CFRP) reinforcement, which requires only a small concrete cover to meet bond requirements. Regarding the component's topology, material-efficient ribbed or waffle slabs have been built for decades but their execution has declined owing to their labour-intense production, which calls for manual installation of the formwork. A recently proposed extrusion manufacturing process combines both approaches for material-minimised construction and allows the fast and formwork-free production of carbon reinforced concrete (CRC) components. This article describes the concept, the finding of the form, fabrication and experimental testing of an innovative ribbed floor slab composed of precast extruded carbon reinforced concrete (ExCRC) webs. The novel floor slab consists of a conventionally cast thin-walled top slab and shaped, load-adapted ExCRC webs to achieve high utilisaton of the structural member. The ribbed slab provides a lightweight structural system with drastic savings in dead load compared with a conventional steel reinforced slab. In addition, the high durability and service life of the novel floor slabs makes them ideal components to be recovered after an initial life cycle and to be re-used in new construction projects. The paper gives an outlook to the full-scale production of one-way and two-way slab systems made of ExCRC such as ribbed slabs, waffle slabs and sandwich slabs with a honeycomb infill. [ABSTRACT FROM AUTHOR]

The quality of strain measurements using distributed fiber optic sensors (DFOS) depends largely on the bond between the host material and the optical fiber. Experimental investigations were carried out to test the suitability of five different DFOS types for crack monitoring. The DFOS were subsequently bonded to two 4 m long reinforced concrete (RC) beams, so that the influence of the application technique could be evaluated. DFOS measurements were verified by digital image correlation (DIC) and electrical strain gauges (SGs). For the different DFOS types, clear differences in the measured strain curves and determined crack widths were observed. The focus was on two robust DFOS, which can be deployed on construction sites. Compared to the layered sensing cable, a monolithic DFOS showed a clear strain distribution with pronounced strain peaks even for closely spaced cracks. The crack widths obtained by integrating the strain curves showed high agreement with DIC measurements. [ABSTRACT FROM AUTHOR]

Concrete bridges with low shear reinforcement ratios erected in the mid‐20th century are subjected to rapidly increasing traffic loads in the last decades. In the absence of precise methods for assessing the remaining service life, the detection of the slightest damage (e.g., cracks and corrosion) immediately leads to a partial or complete restriction of traffic. Major parts of the ultimate fatigue capacity are therefore not yet utilized. Addressing the aspects of sustainability and capacity of traffic infrastructure, it is crucial to extend the service life of existing bridges by optimized assessment concepts that cover the development of the actual damage state of the critical structural components. Therefore, this paper presents a novel monitoring concept for the strain development of pre‐damaged concrete structures. First experimental studies demonstrate that Fiber Optic Sensors (FOS) are ideally suited to capture the strain development of concrete structures under fatigue loading. Therefore, the developed measurement concept is based on this technology and can contribute to extend the service life of concrete bridges through comprehensive monitoring strategies. [ABSTRACT FROM AUTHOR]

A new composite column system using a solid core and an encasing jacket made from (ultra‐)high‐strength structural steel filled with concrete is presented in this paper that can serve as a promising alternative to prefabricated reinforced concrete columns from an economic and constructive point of view. Within the scope of a research project, this topic is being investigated in more detail by means of numerous experimental and theoretical investigations to enable the use of (ultra‐)high‐strength steels in the future. In this article, stub column tests were carried out to assess the resistance to pure compression and to gain insights into the structural performance of this new composite column system. Novel measurement techniques are used to evaluate the different normal force bearing components of the steel core, the hollow steel section, and the filled concrete over the entire loading process. A clear dependence of the load‐bearing behaviour on the cross‐sectional shape and the load introduction form (full‐surface load introduction vs. load introduction via the core surface) was observed. [ABSTRACT FROM AUTHOR]

Crigler–Najjar Syndrome (CNS) with residual activity of UDP-glucuronosyltransferase 1A1 (UGT1A1) and no need for daily phototherapy is called mild Crigler–Najjar Syndrome. Most of these patients need medical treatment for enzyme induction (phenobarbital) to lower blood levels of unconjugated bilirubin (UCB). Apart from this, no long-term problems have been described so far. The phenotype of patients with the homozygous pathogenic variant c.115C>G p.(His39Asp) in UGT1A1 is described as variable. Clinical observations of our patients led to the assumption that patients with variant c.115C>G have a mild CNS phenotype while having a high risk of developing progressive liver disease. For mild CNS disease, progressive liver disease has not been described so far. Therefore, we conducted a retrospective multicenter analysis of 14 patients with this particular variant, aiming for better characterization of this variant. We could confirm that patients with variant c.115C>G have a high risk of progressive liver disease (seven of fourteen), which increases with age despite having a very mild CNS phenotype. Earlier predictors and causes for an unfavorable disease course are not detectable, but close follow-up could identify patients with progressive liver disease at the beginning. In conclusion, these patients need close and specialized follow-up. Our study questions whether fibrosis in the CNS is really driven by high amounts of UCB or phototherapy. [ABSTRACT FROM AUTHOR]

Due to climate change and current efforts to reduce emissions in the construction sector, this study evaluates and discusses the results of a comparative cradle-to-grave Life Cycle Assessment (LCA), with a main focus on Global Warming Potential for functionally equivalent carbon-reinforced concrete (CRC) and steel-reinforced concrete (SRC) façade panels for the first time. The novelty of this study is the focus on construction waste and, in particular, the worst-case application of non-recycled construction waste. The use of CRC requires a lower concrete thickness than SRC because the carbon fiber reinforcement does not corrode, in contrast to steel reinforcement. Façade panels of the same geometrical dimensions and structural performance were defined as functional units (FU). Assuming an End-of-Life (EoL) scenario of 50% landfill and 50% recycling, the Global Warming Potential (GWP, given in CO2 equivalent (CO2e)) of the CRC façade (411–496 kg CO2e) is shown to perform better than or equal to the SRC façade (492 kg CO2e). Changing the assumption of CRC to a worst-case scenario, going fully to landfill and not being recycled (single life cycle), turns the GWP results in favor of the SRC façade. Assuming a 50-year service life for the SRC façade panel and relativizing the emissions to the years, the more durable CRC façade performs much better. Finally, depending on the system boundary, the assumed EoL and lifetime, CRC can represent a lower-emission alternative to a functionally equivalent component made of SRC. The most important and "novel" result in this study, which also leads to future research opportunities, is that delicate adjustments (especially concerning EoL scenarios and expected service life) can lead to completely different recommendations for decision-makers. Only by combining the knowledge of LCA experts, structural engineers, and builders optimal decisions can be made regarding sustainable materials and building components. [ABSTRACT FROM AUTHOR]

Copyright of Beton- Und Stahlbetonbau 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.)