bluuebunny/crossref_metadata_2025 huggingface dataset:
Emergency Care Unit and Patient Satisfaction, During Covid-19 Pandemic: Durres Hospital Case
Authors: Kalaja Rezarta
Published: June 2022

The outbreak of covid-19 is having a significant impact on both the physical and social environment. Over 108.2 million people still uncounted (1). Among the sectors of a hospital, the emergency service is one of the most challenging in relation to the promotion of care quality. Achieve good levels of satisfaction of patients of these services is a difficult task (2) due to weaknesses caused by overcrowding, lack of hospital beds, lack of human resources and inadequate physical infrastructure to meet all demand (3). The difficult situation created, during the pandemic outbreak, focused the entire influx of patients, in the emergency service, which encountered the initial difficulties, of facing a completely unknown and unimaginable crisis, deepening the above problems. Patient satisfaction, as a perception and an attitude that a consumer can have or view towards a total experience of health care, is a multidimensional aspect, which represents a vital key marker for the quality of health care delivery (4). The purpose of this study is to assess patient’s satisfaction with the emergency service in the regional hospital of Durres, during Covid-19 pandemic period, as well as to identify the main problems that led to patient’s dissatisfaction with the quality of service. In a for month period, 200 patients who received services at this hospital while affected by covid-19, were interviewed. A structured questionnaire was used to collect data from participants. The collected data were processed by SPSS statistical software. The main result of the analysis, showed that 62% of the respondents were satisfied with the service received, and that the degree of dissatisfactions on the rest of the patients was mainly related to the large number of patients hospitalized ate the same time, which created uncertainty among patients, about the service received and the fear to neglect. Preparing staff to deal with such critical situations is a must, as a good proportion of patients often perceived the insecurity of physicians and nurses in providing first aid. The overall opinions about the satisfaction level of patients for the availability and empathy of doctors in the hospital were good. As a conclusion we can say that there is a strong positive relationship between patients satisfaction and the promptness in the service as well as the necessary spaces for the treatment of patients.
Comment on “Following molecular mobility during chemical reactions: no evidence for active propulsion” and “Molecular diffusivity of click reaction components: the diffusion enhancement question”
Authors: Huang Tian , Granick Steve
Published: June 2022

We provide arguments why we consider as inaccurate two recent JACS Communications which disagree with this laboratory’s report of boosted diffusion during the copper-catalyzed azide-alkyne cycloaddition click reaction (CuAAC). Fillbrook et al. claim that their diffusion NMR experiments offer no evidence for boosted diffusion, but their use of Gd3+-chelates to speed up NMR relaxations times is flawed conceptually, the authors interpreting Gd3+-chelates as inert. Actually, the same features that make gadolinium ions useful as contrast agents in magnetic resonance imaging render them unsuitable for diffusion NMR. Nonetheless, by correctly adjusting technical aspects of measurement, we confirm boosted diffusion even in the presence of this MRI contrast agent. The second skeptical Communication, by Rezaei-Ghaleh et al., compares to a reference state that is not meaningful physically.
In situ Study of Au Nanoparticle Growth in a Mechanochemical-Aging-Based Synthesis
Authors: Richard Austin , Ferguson Michael , Fiss Blaine , Titi Hatem , Valdez Jesus , Provatas Nikolas , Friscic Tomislav , Moores Audrey
Published: June 2022

As we strive to perform chemical transformations in a more sustainable fashion, inducing reactions through the absorption of mechanical energy has emerged as a highly successful approach. Due to the wide-ranging applications of gold nanoparticles (AuNPs), mechanochemical strategies have already been employed for their synthesis. However, we do not yet fully understand the underlying processes surrounding the gold salt reduction, nucleation and growth of AuNPs in the solid state. Herein, we present a mechanically activated aging synthesis of AuNPs, through a solid-state Turkevich reaction. Solid reactants are only briefly exposed to mechanical energy before being aged statically for a period of six weeks at different temperatures. The aging step grants a greater period of time to analyze the initial reduction and subsequent nanoparticle formation processes. During the aging period the reaction was monitored using a combination of X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM) to gain meaningful insights into the solid-state formation of gold nanoparticles.
Características de la desinformación en redes sociales. Estudio comparado de los engaños desmentidos en Argentina y España durante el 2020
Authors: Gamir-Ríos José , Tarullo Raquel
Published: June 2022

Este trabajo estudia los principales rasgos de las desinformaciones que circularon en redes sociales en Argentina y España durante el año 2020, así como sus similitudes y diferencias. La investigación aplica un análisis de contenido de siete variables a 402 engaños desmentidos en ambos países por los medios verificadores Chequeado y Newtral. En concreto, se estudian las fuentes de las desinformaciones, su tipología, los protagonistas y sus atributos, su adscripción temática, las emociones a las que apelan y los rasgos populistas que presentan. Los resultados evidencian el predominio de (a) fuentes anónimas en ambos países, de fuentes reales mediáticas en Argentina y de fuentes políticas suplantadas en España; (b) el engaño como forma de desinformación; (c) la clase política como protagonista, casi siempre con una transmisión de atributos negativos; (d) la salud como tema principal, aspecto derivado de la pandemia del COVID-19, seguido por la calidad de la democracia, en Argentina, y por el consumo y cuestiones políticas personales, en España; (e) la apelación a emociones negativas, especialmente la ira y el miedo, propias de la polarización afectiva negativa; y (f) el ataque a las élites y la defensa de los intereses de la ciudadanía como rasgos discursivos populistas.

Este trabajo estudia los principales rasgos de las desinformaciones que circularon en redes sociales en Argentina y España durante el año 2020, así como sus similitudes y diferencias. La investigación aplica un análisis de contenido de siete variables a 402 engaños desmentidos en ambos países por los medios verificadores Chequeado y Newtral. En concreto, se estudian las fuentes de las desinformaciones, su tipología, los protagonistas y sus atributos, su adscripción temática, las emociones a las que apelan y los rasgos populistas que presentan. Los resultados evidencian el predominio de (a) fuentes anónimas en ambos países, de fuentes reales mediáticas en Argentina y de fuentes políticas suplantadas en España; (b) el engaño como forma de desinformación; (c) la clase política como protagonista, casi siempre con una transmisión de atributos negativos; (d) la salud como tema principal, aspecto derivado de la pandemia del COVID-19, seguido por la calidad de la democracia, en Argentina, y por el consumo y cuestiones políticas personales, en España; (e) la apelación a emociones negativas, especialmente la ira y el miedo, propias de la polarización afectiva negativa; y (f) el ataque a las élites y la defensa de los intereses de la ciudadanía como rasgos discursivos populistas.
Rehabilitation After Surgical Treatment of Pectoralis Major Rupture in a CrossFit® Practitioner: A Case Report
Authors: da Silva Lucas Gomes , Ferrer Rafael Marques , de Souza José Roberto , Gracitelli Mauro E.C. , Secchi Leonardo Luiz Barretti
Published: June 2022

Background and Purpose

The upper limbs are frequently injured during CrossFit® practice, and in some cases, surgical repair is recommended. The purpose of this case report was to describe the rehabilitation process performed after the surgical repair of a pectoralis major rupture in a CrossFit® practitioner.

Design

Case report.

Case Description

The subject was a 26-year-old man, with 1.75m and 69kg, who practiced CrossFit® for five years and sustained the injury during the execution of the ring dip. The rehabilitation protocol was of 16 weeks duration. Passive modalities and exercises focusing on range of motion, muscle strength, and CrossFit®-specific movements were performed. Shoulder range of motion was assessed through goniometry, and muscle strength was assessed through isometric dynamometry.

Outcomes

At week seven the subject had full range of motion, and at week fourteen achieved limb symmetry (Limb Symmetry Index - 84.78 – Abduction; 97.58 – Adduction; 86.15 – Internal Rotation; 85.06 – External Rotation) in muscle strength. The subject returned to his previous level of athletic activities.

Conclusions: A 16-week protocol performed with exercises focusing on range of motion, muscle strength, and CrossFit®-specific movements was abe to promote the return to sport at the pre-injury level in a CrossFit® practitioner.
Incidencia del modelo pedagógico en la calidad superior
Authors: Tuay Sigua Rosa Nidia
Published: June 2022

Aunque son diversos los problemas para tratar en relación con la calidad de la educación, es importante y necesario concentrar la investigación en la importancia de la perspectiva pedagógica. Sin embargo, al presentar las acciones de las instituciones para mejorar la calidad se crea algunas confusiones y trastoques en el desarrollo de estas; igualmente se destaca en la didáctica las propuestas relacionadas con la enseñanza basada en proyectos y el aprendizaje basado en problemas (ABP), que aunque son alternativas al modelo tradicional de transferencia, poco uso se encuentra.
A Gender-Based Analysis of Classroom Interaction Practices: The Effect Thereof on University Students’ Academic Performance
Authors: Rudhumbu Norman
Published: June 2022

The need to optimize student interactions in universities for enhanced academic performance has been a subject of debate and discussion in different academic fora. A number of studies have shown that students, both male and female, can assert themselves academically if they are provided with opportunities for active participation and interaction with their lecturers and peers for both the horizontal and the vertical sharing of knowledge. The purpose of this study, therefore, was to investigate the gender-based interaction practices of science, mathematics and technology university students, and how these interactive patterns influence their academic performance. Using a quantitative approach located in the post-positivist paradigm, the study employed a structured questionnaire to collect the data from a sample of 1285 students from three universities. The results of the study showed that institutional practices, lecturers, parents, peers, learning content and artifacts, as well as the classroom environment, have a significant influence on the gender-based interaction practices of university students. Furthermore,, the results showed that the levels of interaction have a significant influence on the academic performance of university students, according to gender. As a main recommendation, it was proposed that universities should come up with gender-equity policies that would guide how the universities and their stakeholders could cater for the issues of gender equity.
Applying Peer-Review Checklist to Improve Vietnamese EFL University Students’ Writing Skills
Authors: Hanh Le Thi Tuyet , Tinh Bui Thanh
Published: June 2022

This study was an attempt to investigate the effect of peer-review checklists on Vietnamese EFL students’ writing performance and students’ feedback on the application of the peer-review checklist. The quasi-experimental study was conducted with fifty-eight non-English major students at a university in the Mekong Delta. The participants were divided into an experimental group and a control group. A mixed-methods intervention design was applied, in which data were collected from a pre-test, a post-test and a focus-group interview. The results of the triangulation analysis, which compared datasets from the instruments, revealed that EFL students utilizing a peer-review checklist performed better than did their peers in the control group. More specifically, students in the experimental group had significant progress in terms of task fulfilment and utilizing vocabulary. The results also indicated that most students’ feedback on the use of the checklist was positively noticed. Although the findings of the study are limited because of the small sample, use of peer review checklists in writing classes is recommended for EFL students in tertiary contexts with some suggested cautions.
Multilevel FEA and BIM for the design of structural steel
Authors: Wald František , Kožich Matyáš , Šabatka Lubomír , Chalupa Vojtech , Vild Martin
Published: June 2022

Connection modeling and analysis are vital parts of the design of steel structures. The paper introduces the stakeholders participating in the design of steel structures and their joints. Then briefly describes the motivations and requirements of the three key stakeholders, inputs they use, and outputs they produce. The data needed for connection design are presented, as well as the possibilities of their sharing. A comparison and impact of three different levels of BIM implementation is demonstrated in practical case studies.
Extrapolation of Test Data in Time, Size and Risk: A Challenge for Concrete Design Codes
Authors: Bažant Zdeněk P. , Dönmez A. Abdullah
Published: June 2022

It is no secret that the lifetimes of concrete structures have been inadequate, and that structural failures are far too common, especially in the case of large structures of novel designs. This problem has two aspects: 1) randomness of loads such as those from traffic, environment and random vibrations, and 2) the uncertainty in material properties, role of corrosive agents, and failure mechanics. Significant progress has been achieved in the first, but less in the second, which is a problem of extrapolation. The second is just as important, yet has been mostly neglected by structural safety specialists. Only the second aspect is discussed in this lecture, and only in qualitative, non-mathematical, terms. A broad vision of the extrapolation problem is offered. Lapses of quality control are a different problem, not discussed here.
UHPFRC is ready to revolutionize existing and new structures
Authors: Brühwiler Eugen
Published: June 2022

“Structural UHPFRC” stands for Ultra‐High‐Performance Fibre Reinforced Cementitious Composite material which is complemented by reinforcing and prestressing steel to enhance the resistance and durability of structural elements. Properties of impermeable, tensile strain hardening UHPFRC are discussed in view of structural applications. Two fundamental concepts to enhance concrete bridges have been developed by research and validated by numerous applications, mostly in Switzerland:

1) Rehabilitation and strengthening of existing concrete structures by adding a layer of structural UHPFRC, and 2) Construction of new structures in Structural UHPFRC, often composed of precast elements. These applications show that “Structural UHPFRC” has made its proof as a novel building material and technology to enhance bridges and structures in general. UHPFRC also contributes in lowering the environmental impact of structures and thus improving sustainability. UHPFRC is at the beginning of a new construction era: the “post‐concrete era”.
The New Storstrøm Bridge – Pier Design
Authors: Needham Mike , Collins James
Published: June 2022

The New Storstrøm Bridge in Denmark has 40 concrete piers ranging from 18 to 35m high. The piers comprise multi-faceted stems and pier heads. To simplify offshore construction a precast segmental solution was used, with a prestressed insitu pier head. The design was optimised through parametric analysis including non-linear modelling and automated calculation reporting. A modular approach maximised repetition of segments between different pier heights to enable precast construction in a factory environment prior to assembly offshore. Non-linear dynamic modelling was used to validate resistance to ship impact. Detailed analysis of the insitu joints between segments was undertaken, using headed bars to provide the required anchorages. The pier head was designed using finite element models to confirm the strut and tie behaviour and a prestress layout that minimised external pockets.
Economical Steel Bridges
Authors: Gagné Martin , Duran Bernardo , van Leeuwen Martin
Published: June 2022

Steel is an economical choice for bridge construction for a number of reasons, including its high strength, its light weight, as well as its resiliency in the face of extreme weather events or natural disasters. Duplex zinc coatings for steel structures consist of a metallic zinc coating, typically hot dip galvanized (HDG) or thermal sprayed zinc (TSZ), painted with a protective organic coating. The time to first maintenance of a duplex coating can easily be twice the life of the individual metallic zinc and paint coatings alone. Life-cycle cost modeling compares material and design alternatives over the entire life of the structure. Life cycle costs models have shown the benefits of using duplex zinc coatings for corrosion protection to reduce the total cost of ownership of steel bridges, as well as to show that steel bridges are competitive with concrete structures for short spans.
Methods and technologies for evaluating and minimising noise from road bridge expansion joints
Authors: Mettner Knut , Jelínek David , Meng Niculin
Published: June 2022

Noise generated by traffic crossing road bridges can be a major source of disturbance for local communities and must be carefully considered in planning bridge construction and maintenance projects – especially when specifying expansion joint solutions, since expansion joints are typically mechanical components that introduce discontinuities or unevenness into an otherwise smooth driving surface. The consequences of not adequately considering the potential impact of noise on a community can be substantial, with public relations difficulties and high adaptation or replacement costs. This paper explores the subject of noise associated with bridge expansion joints, including an assessment of what types of joint may be considered quiet, and how noisier types – such as modular or single-gap joints – may be made quieter. Approaches to evaluating noise and what should be considered are discussed, with reference to findings from illustrative noise measurement studies.
Experimental Database on Resistance of Hybrid Joints with High- strength Bolts and Epoxy Adhesive
Authors: Moriyama Hitoshi , Yamaguchi Takashi
Published: June 2022

High-strength frictional bolted joints is a usual connecting method of steel members at a construction site. Epoxy putty is also used to adjust the unevenness of corroded member’s surface in a repair with bolted connections. Thus, the repair is often conducted by hybrid joint with epoxy adhesives and high-strength bolts. The conversion to hybrid joints is also effective in terms of the performance enhancement. Therefore, this paper surveys experimental data of the hybrid joints in Japan to summarize essential pieces of information. Surveyed results show that the relationships between the average shear strength of hybrid joints and average contact pressure on the faying surface indicates a strong correlation. Therefore, hybrid joints have the strength characteristic of adhesive joints rather than frictional bolted joints. Moreover, approximate equations which can evaluate the peeing resistance of the joint composed of several bolts was proposed.
Load transferring mechanism of long riveted joint partially replaced by high-strength bolts
Authors: Chen Yu , Sakura Ryo , Yamaguchi Takashi , Hayashi Gen , Yamauchi Motoshi , Ueno Keita
Published: June 2022

Rivet joints are widely applied in the connections of steel bridges prior to 1950 owing to their tightness and strength. Some rivets become loosened or corroded after repeated loading and long- term usage. Previous studies indicate that replacing riveted joints with a high-strength bolt to achieve friction may be the best approach for repairing a riveted joint. However, for a long riveted joint, which has an uneven load distribution, the removal of individual rivets may overload the other rivets. This study focuses on long riveted joints at the bottom flange of an actual riveted bridge. The load redistribution mechanism involved when the rivet is removed under a dead load is investigated by performing a finite element (FE) simulation. The FE analysis results show that when a rivet is replaced by a bolt, the rivet’s load transferring ability is affected more by rivets near the bolts, whereas more distant rivets pose almost no effects.
A state-of-the-art, flexible, easy-to-replace plug-type expansion joint for the Delaware Memorial Bridge
Authors: Kovach Forest , Moor Gianni , Ortmann Dominik
Published: June 2022

The modern flexible plug expansion joint, which uses a special polyurethane material rather than the asphaltic material traditionally used, has been developed to offer an optimal small-movement expansion joint solution, in many cases, to bridge construction and maintenance engineers. Its long- term performance is vastly superior to that of the asphaltic plug joint – thanks, for example, to its great strength and elasticity (with the material allowing 650% elongation before failure), its resistance to both very low and very high temperatures, and the special advantages it offers when used to replace old joints in existing structures with minimum impact on traffic. The expansion joint is described, in terms of properties, benefits and installation, with reference to an ongoing project to replace the expansion joints of the Delaware Memorial Bridge.
Monitoring and Assessment of Bridge Cable Stays Consisting of Bundles of Fully Locked Coil Ropes
Authors: Ároch Rudolf , Kováč Michal , Klas Tomáš , Štecák Róbert , Venglár Michal
Published: June 2022

The paper describes the health monitoring of the cables of the largest cable-stayed bridge in Slovakia. The bridge spans the Danube River and is located in Bratislava. It was opened for traffic in 1972. The bridge is known for the restaurant at the top of its inclined pylon. The cables consist of bundles of fully locked coil ropes.

The vibration method was used to assess the forces and damping of the cables. The results were compared with the topographical measurement method. The distribution of the total force in the stays among the individual fully locked coil ropes was also investigated by the vibration method. The measurement was performed in the anchor chambers in the bridge beam where the bundles of ropes spread out. Due to the short lengths of the ropes, the influence of their bending stiffness had to be considered. A non-linear fitting procedure with minimising the sum of squares was used.

A set of up to nine accelerometers was used to measure the vibration of individual ropes. A study on the number of necessary considered mode shapes was also performed. Ambient vibrations were used for the operational modal analysis and impact loads coming from a hammer were used for excitation as well.
Shear design of composite columns with sheet metal sections
Authors: Mensinger Martin , Schäfers Michael
Published: June 2022

Composite columns offer an efficient solution for vertical elements in high-rise buildings through high load bearing capacities and fire safety. Until now, such sections have been constructed with either rolled or solid profiles as core element. Residual stresses of such core profiles often cause inefficient use of material due to the reduction of yield strengths. This paper presents a new form of composite columns consisting of metal sheets as core profile with optimized shear connection. Advantages are expected from a reduction of residual stresses due to smaller thicknesses of each partial core as well as adjustable flexural rigidity settings, as shear connecting elements can be installed locally where needed. Deployment of high strength steel helps increasing the bearing capacity significantly.
Damage detection in concrete with coda wave interferometry using a 60 kHz ultrasonic signal
Authors: Grabke Stefan , Bletzinger Kai-Uwe , Wüchner Roland , Clauß Felix , Ahrens Mark Alexander , Mark Peter
Published: June 2022

Coda wave interferometry is an ultrasound-based possible candidate for structural health monitoring of concrete structures. It is based on a correlation evaluation of two ultrasonic signals. A perturbation, e.g., cracks in the medium are causing changes in the signal. The correlation development over the signal’s length is very characteristic for the position of the crack relative to source and receiver. This development can be modeled and allows to state an inverse problem whose solution localizes a new perturbation, e.g., crack in the medium.

An application at a four-point bending test of a reinforced concrete specimen with a span of 3.5 m and 25 ultrasonic transducers with a used central frequency of 60 kHz shows promising results for damage detection. The coda technology can successfully distinguish multiple developing cracks and results are compared to fiber optic sensor measurements. Some problems like cracks that develop into the installation position of the ultrasonic transducers are also found and solutions are proposed.
Structural analysis of a historical masonry arch railway bridge in Gata de Gorgos, using a generic finite element analysis software
Authors: Tarín Pablo , Ordiñana Alberto , Ibáñez Fernando
Published: June 2022

The rehabilitation and deck widening of the masonry viaduct over the river Gorgos, built on 1913, is included in the renewal of the historical Alicante railway net. The primary aim of the rehabilitation work was to repair the bridge’s deficiencies caused by the deterioration of the structure, upgrade its capacity to resist the loads included in modern codes and fulfil the railway safety requirements defined by the owner. A bidimensional FE model was carried out in order to assess the structural behaviour of the viaduct, confirming that no global failure occur under the current design loads.
Railway bridges - Monuments in the network
Authors: Monka Johanna , Marx Steffen
Published: June 2022

Since the 1830s, the railway network has grown rapidly, connecting all regions of the German country. In order to overcome topographical obstacles such as valleys, rivers etc., many railway bridges were built in different construction periods. The individual structures are understood as elements of the dynamic development of the complex "railway" network. Railway bridges are constantly changing structures, as their functionality and preservation value must be secured through maintenance, repair and replacement due to increased requirements. During the beginning of railway expansion, especially in Saxony, a dense network was developed. The topography of a low mountain region led to a high number of arch bridges. This type of construction still makes up a high proportion of the existing bridges in Saxony today. The history of selected railway arch bridges from representative parts of the railway network in Saxony is shown and analysed.
Assessment of masonry arch bridges
Authors: Harrewijn Thomas , Vergoossen Rob
Published: June 2022

This paper is about the assessment of masonry arch bridges in the Netherlands. A large part of the public road network in old city centres is still formed by masonry arch bridges. The general question of the local authorities is “can masonry arch bridges withstand motorised traffic including busses and occasionally heavy trucks?” Nonlinear finite element analysis in PLAXIS is applied for the assessment of the failure behaviour of the structure and its limits related to cracking and failure loading. A proof-loading of a real bridge increased the reliability of the calculation methodology. To assess a large group of single span masonry arch bridges, suggestions for a risk-based approach are made.
An experimental investigation on base-plate joints of steel storage pallet racks
Authors: Baldassino Nadia , Bernardi Martina , Zandonini Riccardo
Published: June 2022

Adjustable storage pallet racks are framed structures commonly made of cold-formed steel profiles. The performance of these structures is strongly influenced by the beam-to-column and the base- plate joints behaviour. The key role of joints is even more significant in seismic loading conditions. The complexity of their non-linear and non-symmetric behaviour calls for their experimental characterisation both in monotonic and cyclic range. In recent years, attention has been paid to the study of beam-to-column joints, while the knowledge on the base-plate joints response is still quite limited. This gap is even more evident when the cross-aisle (transversal) direction and the cyclic range are considered. The research presented in this paper focuses on the monotonic and cyclic experimental response of a typical rack base-plate joint, tested both in down-aisle (longitudinal) and cross-aisle direction. The main features and outcomes of the study are presented and discussed.
Investigating out-of-plane strength & stiffness of a nailed glulam connection
Authors: Kvist Rebecka , Ranefjärd Oskar , Alyaseen Hiba , Thelandersson Sven
Published: June 2022

During March 2020 a large-span arena, Tarfalahallen, collapsed. The main load-bearing girders with a 54 m span were high and slender glulam trussed beams, supported from below by a cable system via vertical struts. Investigations concluded that the failure was initiated by out-of-plane buckling of the struts and slender beam, in spite of lateral stabilization by steel roof sheeting at the top edge of the beam and by glulam rods at the lower end of the strut where the cable system was attached. The nailed connection between strut and main glulam beam was not stiff enough to prevent buckling. In this study a nailed connection similar to that used in the arena, though on a smaller scale, was tested under combined bending and axial loading. The biaxial testing simulates vertical loading in the strut combined with out-of-plane loading created by second order effects. It was found that the out-of-plane stiffness is reduced when vertical loading is at high levels.
BIM and BMS: Current Status and Challenges
Authors: Hajdin Rade , Samec Vanja
Published: June 2022

Bridges are a vital, but also extremely vulnerable part of transportation infrastructure. The design and construction of a bridge have a large influence on its longevity although these phases are short compared to its life span. It is therefore essential that, at the acceptance the bridge together with the accurate as-built information is delivered to the owner.

A bridge owner relies on an as-built high-quality information and on information on bridge condition to initiate interventions that ensure its safety and serviceability. The information on bridge condition is obtained by regular inspections as well as monitoring activities. During the lifetime of a bridge these diagnostic activities may generate huge amount of data that needs to be managed. With changing environmental actions, accurate and usable information from the inspection and monitoring – in conjunction with as-built data - is essential for efficient and timely maintenance planning. Inspections and maintenance planning require organized, automated, open and intuitive digital processes, which should consider both object data and related condition data. This seamless digital process is supported by existing Bridge Management Systems but can be vastly improved. In particular, most BMS don’t support geometric representation that render data collection during inspections quite tedious.

The introduction of BIM in BMS can substantially facilitate the collection of inspection data and accurately localize monitoring data. Moreover, the exact geometry of bridges can enhance maintenance planning by simulation of structural behavior of as-is structure under different environmental actions.

BIM's incorporation would evolve BMS into a fully digital storage system and a platform for data exchange with existing BIM solutions as well as for maintenance planning that include deterioration forecast, optimization and analysis models.

The vision includes 3D+ software and hardware independent data exchange between different software technologies during life span and beyond. Open BIM technology for the interoperability from technical, semantic and organizational point is of main interest.

Current status of development and challenges that need to be overcome for successful fulfilment of the presented vision are discussed.
Data driven BIM models in bridges
Authors: Partala Eetu
Published: June 2022

Design automation tools are rarely used in a context of existing structures. The methods of modelling can also be harnessed to create digital twins of structures with the help of data from the structural health management systems. With 10 pilot bridges, the workflow was studied and key parameters for the modelling specified. Semi-automated modelling process made it possible to create models from bridges that were designed and built before the BIM era.
Bridge Condition Assessment Based on Image Data and Digital Twins
Authors: Taraben Jakob , Helmrich Marcel , Morgenthal Guido
Published: June 2022

Many different approaches using modern digital technologies were recently developed to support engineers with the acquisition of visual inspection data, such as the usage of small unmanned aircraft systems (UAS) equipped with high-quality cameras. The images obtained are used, amongst others, for photogrammetric reconstruction methods or image-based anomaly detection, which leads to a high potential of automation in condition assessment, reducing time and costs. This article presents approaches for the integration of image-based inspection data sets into an automated workflow towards condition rating of damaged infrastructures. To this end, it is shown how 3D annotations are combined with information from a digital twin, such that further properties are assigned to the detected structural anomalies, in order to enrich the digital twin. Finally, the proposed methods are applied to a case study to show the feasibility in a practical use case.
Study on Fatigue Durability of Steel Box Girder Corner Plate Weld with Peening
Authors: Nishishiba Takamitsu , Takada Yoshihiko , Kumazawa Misa , Okamoto Ryoji , Tateishi Kazuo , Shimizu Masaru
Published: June 2022

Corner plates are sometimes added to the web-to-flange joints of box girder bridges by welding on a single side to increase stiffness. In the case of the Minatogawa Bridge on the Hanshin Expressway, a steel box girder with low girder height and corner plate was used to reduce the weight of the superstructure. In this bridge, many fatigue cracks were observed in the welds of the corner plates.

As a crack suppression measure, the end of corner plate was cut-out in U-shape. Although the stress concentration relaxation reduced the risk of crack initiation, the risk of crack initiation starting from the un-welded area still remains.

In this study, we focused on peening as a countermeasure to improve the fatigue endurance. As a result, it was confirmed that peening to the un-welded area was effective in improving the fatigue endurance.
Cracking and Fatigue of Heavy Loaded Prestressed Concrete Bridge in Sweden
Authors: Agredo Chávez Angélica , Gonzalez-Libreros Jaime , Andersson Kasper , Leidzen Jon , Andersson Erik , Petersson Mats , Sas Gabriel , Elfgren Lennart , Häggström Jens
Published: June 2022

A prestressed concrete bridge was built in 1963 with BBRV cables. It has three spans and a total length of 134.8 m. Due to mining activities the bridge was loaded with trucks with a total weight of 90 ton during 2012-2014 and from 2019. Crack development has been monitored manually and from 2020 with strain gauges and LVDTs. Cracks normally vary between 0.1 to 0.3 mm in width and grow in length with time. In November 2020 some of the strain gauges on the concrete showed alarming growth and the bridge was closed for traffic. Additional strain gauges were installed on vertical reinforcement bars and an assessment was carried out of the fatigue capacity of the bridge. It was found that the new strain gauges did not indicate any growth in strain and that the fatigue capacity was sufficient. The bridge could be opened again for traffic after being closed for five weeks. Monitoring drift in the strain gauges and fatigue are discussed.
Influence of Material Stiffness on Bond Behaviour for CFRP and BFRP Strips Glued to Concrete Surface
Authors: Grzesiak Szymon , Pahn Matthias , Schultz-Cornelius Milan
Published: June 2022

In the last years, the development of fibre reinforced polymers poses new challenges in the creation of new construction and in retrofitting of old buildings and in some cases also bridges. Advanced solutions for refurbishment and strengthening should be an alternative to demolishing old structures and building new ones. One of the established retrofitting methods is the system with carbon fibre reinforced polymer (CFRP) strips. New and innovative materials like basalt fibre reinforced polymer (BFRP) strips can replace well-known CFRP. So far more extensively analysed are the mechanical properties of composites materials like tensile strength, modulus of elasticity and fracture point. Till yet unexplored field of BFRP strips is the bond stress-slip relationship on the concrete surface. This unexplored field is necessary for the calculation of external reinforcement in concrete elements. The aim of this article is to investigate the force transfer between the concrete member and BFRP strips. The intermediate crack element specimens were carried out. The experimental part serves to determine the bond stress–slip relationship of BFRP glued to concrete. In this paper, the effect of material stiffness on the load-bearing behaviour of reinforced concrete structures strengthened with BFRP strips will be considered.
Condition Assessment of Steel Riveted Roof of Heritage Building in Sofia, Bulgaria
Authors: Dakov Dimitar , Belev Borislav
Published: June 2022

The findings of a recent survey on the steel roof structure of an early-twentieth-century building located in Sofia, Bulgaria are reported. The steel roof structure is supported by solid masonry walls around the building perimeter and on slender cast-iron columns along two interior longitudinal lines. The south part of the building was severely damaged during the bombing raids over Sofia in WWII. The building underwent a major refurbishment within the 1995-2000 period accompanied by detailed survey and condition assessment of the steel roof structure. In 2020 the authors carried out a survey for condition assessment of the steel roof structure including checks of riveted connections, analysis of chemical composition by OES metal analyser and inspection of the roof cladding components by endoscopic device.
European Harmonized Design for Membrane Structures
Authors: Uhlemann Jörg , Stranghöner Natalie
Published: June 2022

Numerous activities of the last years to harmonize and standardize design procedures for membrane structures made from structural textiles or foils lead to a new European standard expected to be published in 2022: CEN/TS 19102 “Design of tensioned membrane structures”. This document is a milestone on the path to a Eurocode for membrane structures. First time it provides unified design rules harmonized among many experts in the field across Europe. It covers coated and uncoated fabrics as well as foils, mechanically as well as pneumatically prestressed structures. Ultimate and serviceability limit state approaches are based on the concepts of EN 1990. The new standard gives the frame for materials and their requirements, static verification of materials and connections, and it defines required experimental tests. It is also planned to provide execution rules together with the design rules in order to ensure reliable and safe membrane structures. This contribution gives an overview of the new standard and shows the approaches by means of examples.
Weathering-induced ageing strength modification factors for PET-PVC-fabrics
Authors: Asadi Hastia , Uhlemann Joerg , Stranghoener Natalie
Published: June 2022

The design process of tension fabric structures must consider changes of the material properties due to long-term exposure to the environment. In line with the harmonized view of the Ultimate Limit State verification which is currently developed in the framework of a novel European design standard for membrane structures, a strength modification factor considering ageing effects is proposed to describe the deterioration arising from environmental impacts. The objective of this paper is to broaden the data basis for the long-term behaviour of a typical structural membrane made of PET-PVC material for environmental impacts. In this way, an overview about different data achieved from two practical applications and experimental artificial weathering tests is presented for the destructive effect of weathering on tensile strength of coated woven fabrics. Finally, related weathering-induced ageing modification factors are derived.
How truck-platooning changes the extreme values of load-effects in single-span bridges.
Authors: Ralbovsky Marian , Vorwagner Alois , Kwapisz Maciej
Published: June 2022

The load model defined in EN 1991-2 is derived from traffic measurements taken in Auxerre (FR) in 1986. Since then the vehicle industries have changed a lot. For different future traffic scenarios, changes in load patters are expected. Automated driving, especially truck platooning, will have an impact on future bridge loads. Due to synchronization of traffic flows, or reduced distances between trucks- as it is used for truck platooning- increase of the traffic load per road meter follows. Within this paper, a large-scale parameter study of different bridge types loaded with randomised traffic flows and platoon scenarios is investigated. Structural safety is evaluated for concentrated vertical forces with dynamic resonance interaction on bridges with respect to randomized traffic. Key parameters such as critical intervehicle distances or dynamic load amplification were identified and discussed.
Pedestrian bridge over the River Elbe in Hradec Králové
Authors: Keclík Jiří , Stržínek Viktor , Navarová Lucie , Vráblík Lukáš , Harazim Petr , Kábrt Libor , Elich Martin , Elichová Gabriela , Lombardini Daniela
Published: June 2022

The new bridge over the Elbe River will be a rather unusual structure made of modern materials. The design solution is truly a challenge for the architects, designers and the contractor and requires their close cooperation. In its final statical scheme, the structure forms a virtual Vierendeel truss of variable height. The designing of the structure involves the necessity to cope with many complex details, which are often beyond the limits of applicable design standards and regulations. The contractor will use uncommon technologies for construction of the structure. These methods will facilitate the installation process while carrying an ecological aspect.
1 Triton Square – Structural reuse for low-carbon architecture.
Authors: Sturel Eric , Robertson Andrew , Tayler Henry
Published: June 2022

1 Triton Square is exemplary for how ingenious structural engineering can be instrumental in maximising the value of the existing building stock as part of a low-carbon agenda.

A commercial office development built in the late 1990s in the London West End, 1 Triton Square had been designed to height limits which were no longer relevant when the tenant vacated the premises at the end of a twenty-year lease. When the building owner approached Arup to examine the possibility of enhancing the value of their asset, it was decided, instead of designing a taller new build, to develop a refurbishment and extension scheme, in line with both organisations’ low-carbon agenda.

The proposed scheme included the part-infilling of existing atria and the addition of three new levels, thus increasing the number of storeys from six to nine, and the floor area by 70%. Columns and foundations had to be strengthened to cater for the resulting uplift in loading. The original structure was predominantly a concrete frame, with steel-framed cores. Due to this variety of structural forms as well as to access constraints, a palette of strengthening methods was implemented, including concrete encasement and fibre-reinforced polymer (FRP) wrapping for concrete columns, and concrete encasement and welding of strengthening plates for steel columns. Existing piled foundations were strengthened with small-diameter supplementary piles installed from within the existing basement and connected to them within new pile caps or within a new piled raft, depending on locations.

1 Triton Square has been completed in May 2021, achieving BREEAM Outstanding rating. The structural embodied carbon associated with the redeveloped scheme has been estimated at 136 kgCO2e/m2, to be compared to the October 2020 “best-practice” target of 350 kgCO2e/m2 for a new build, thus demonstrating the pivotal role of structural reuse in reducing carbon emissions.
Torsion of a Norwegian bridge with partial box-action - a case study
Authors: Vestman Victor , Collin Peter , Oudomphanh Southinanh
Published: June 2022

Some old bridges have a truss between the bottom flanges not intended for torsional effects but for transferring horizontal forces. This paper describes the effects of the truss on torsion for a Norwegian three span bridge from 1967, without composite action. Furthermore, the effects of post-installed shear connectors are investigated.

For composite bridges without intended composite action in bending, the effects of the slab preventing the top flanges from moving laterally should not be ignored, since this is important for the deformations of the girders under eccentric loading. Furthermore, the load distribution between the girders for an eccentric load is significantly enhanced if the horizontal truss is considered. The paper also investigates and presents the effects of post-installed shear connectors, with respect to bending stresses in the bottom flanges (moderate effects) and the top flange (large effects).
Available Tests to evaluate Residual Prestressing Forces in Concrete Bridges
Authors: Agredo Chávez Angélica , Gonzalez-Libreros Jaime , Sas Gabriel , Elfgren Lennart , Bianchi Silvia , Biondini Fabio , Kukay Brian
Published: June 2022

The reduction of the structural capacity and eventual collapse of existing concrete bridges is often related to the loss of the initial prestressing forces. This loss can be associated to immediate or time dependent factors such as elastic shortening, creep, relaxation, loading, and cracking, among others. In addition, environmental factors can lead to corrosion of the strands with the subsequent reduction of their area, loss of bond with the concrete and additional cracking which in turn will influence the value of the residual prestress force and the bridge capacity. Therefore, the evaluation of such losses is critical in the decision-making process of defining a financial and environmental cost optimized intervention strategies (e.g., strengthening or replacement). In this paper, a detailed literature review regarding destructive and non-destructive methods for measuring the residual force in prestressed concrete bridges is carried out and used to develop a database of existing experimental tests.