bluuebunny/crossref_metadata_2025 huggingface dataset:
Macroinvertebrados como bioindicadores de la calidad del agua de la parte céntrica del rio Jipijapa - Ecuador
Authors: Osejos Merino Miguel Angel , Merino Conforme Monserrate Cristina , Merino Conforme Martín Verisimo , Solis Barzola Jaime Leonardo
Published: February 2021

La siguiente investigación se desarrolló en la ciudad de Jipijapa con la utilización de macroinvertebrados como bioindicadores de la calidad del agua de la parte céntrica del rio Jipijapa. Uno de los principales problemas del río son las descargas de aguas residuales domésticas no tratadas, debido a que recibe una alta carga de nutrientes y materia orgánica, cuya degradación resulta crítica para la calidad del agua que corre por su cauce. En esta investigación se realizó la evaluación con la utilización de macroinvertebrados bentónicos como bioindicadores de la calidad del agua, empleando la siguiente metodología con la aplicación del índice biológico BMWPA (Biological Monitoring Working Party), la técnica que se usó en el estudio fue la de Surber para la captura de los individuos estudiados, los resultados mostraron que la única orden que se encontró en el área de estudio es Odonata, de esta fueron identificadas cinco familias y seis géneros con un total de 93 individuos analizados, luego del estudio de campo y laboratorio se obtuvo un total de 34 puntos lo cual se encuentra dentro del rango (16-35), concluyendo que la calidad de agua en el rio Jipijapa es mala y muy contaminada según el índice biológico aplicado lo cual evidencia efectos de contaminación.
Causas de hemorragia postparto
Authors: Astudillo Córdova Madeline Carolina , Landín Ramírez Tania Melissa , Vélez Vera Andrea Jeanette , Villavicencio Briones Wendy Vanessa
Published: February 2021

La hemorragia postparto (HPP) es considerada una emergencia obstétrica y es una de las cinco principales causas de mortalidad materna a nivel mundial y la causa principal de mortalidad materna en países de ingresos bajos. La hemorragia posparto es la segunda causa más importante de muerte materna en Ecuador. Por lo anterior se plantea realizar un compendio de las causas de Hemorragias Maternas y así brindar una actualización del tema disponible para el campo médico en general, bajo la premisa de que esta complicación obstétrica no se le ha otorgado la importancia necesaria para entenderla como una real emergencia médica. Considerando las herramientas de búsqueda tecnológicas disponibles se ha de encontrar las publicaciones científicas que nos permita abordar, de manera actualizada, las causas de la Hemorragia postparto. En la revisión bibliográfica realizada hemos encontrado, principalmente que la muerte es completamente evitable si hay un diagnóstico oportuno y una estimación sincera de que las HPP son una emergencia para tratarse como tal. Por ultimo pero no menos importante, ésta complicación femenina no dispone de datos estadísticos vigentes. Un estudio señala como causas más frecuentes: la atonía uterina, los traumas/laceraciones, la retención de retos placentarios post concepción y las alteraciones de la coagulación. Algunos autores consideran a la atonía uterina como la causa más frecuente; responsable del 50 al 70% de las hemorragias post alumbramiento y del 4% de todas las muertes maternas. También, el desgarro del suelo pélvico es una causa a tomar en consideración, ya que el mismo va acompañado de una denervación de la musculatura del suelo pélvico por daño en los nervios pudendos y sacros, a consecuencia de partos vaginales, la cual pudo deberse a la instrumentación empleada en la atención del parto.
Agentes etiológicos de neuroinfección en pacientes con VIH-SIDA
Authors: Puya Quinto Jonathan Aníbal , Rueda Safady Soraya Marjorie , Cueva Albán Paola Alexandra , Merino Aguilar Doreydhee Stephanye
Published: February 2021

El VIH induce un proceso progresivo y crónico, con un espectro enorme de manifestaciones y complicaciones, que va desde la infección primaria hasta infecciones oportunistas, tumores y desgaste. Aquellos pacientes que llegan a una etapa avanzada de la infección con el VIH (SIDA) y con un bajo recuento de células TCD4+, corren mayores riesgos que nos les falla su sistema inmune de desarrollar infecciones oportunistas del sistema nervioso central. Las infecciones de éste, entiéndase neuroinfecciones, básicamente consisten en un proceso irritativo e inflamatorio que afecta fundamentalmente al encéfalo y/o la médula espinal. El diagnóstico de las NI en el paciente con VIH/SIDA todavía representa un gran reto al que se enfrentan diariamente los médicos en su práctica profesional, por ello, conocer sus agentes etiológicos constituye un aspecto clave en dicha labor. El interés por desarrollar el presente estudio ha surgido de lo anterior, y el objetivo ha sido el de recopilar algunas fuentes cientificoacadémicas recientes con las cuales sustentar y referir los agentes etiológicos de neuroinfección (NI) en pacientes diagnosticados con VIH-SIDA. Los resultados, aun siendo escasos, bastaron para alcanzar el objeto propuesto. Sobre la base de las fuentes revisadas en este estudio se concluyó que, entre los agentes de neuroinfección que ha sido reportados en pacientes diagnosticados con VIH-SIDA están: Cryptococcus neoformans, Treponema pallidum, virus John Cunningham (virus JC), Mycobacterium tuberculosis, Virus de Epstein-Barr, Virus del herpes zoster, Pneumocystis jirovecii, Complejo Mycobacterium avium(MAC), Candida spp, Entamoeba histolytica, Giardia duodenalis, Balantidium coli, Strongyloides stercoralis, Blastocystis hominis, entre otros.
Efectividad de la aplicación del programa de salud bucal del seguro social campesino en escolares de la escuela Aurora Estrada del recinto Tres Postes durante el periodo 2018-2019
Authors: Tobar Castillo Erika Lissette , Villamar Páez Christian Antonio , Torres Ávila José Antonio
Published: February 2021

Uno de los aspectos más importantes en el desarrollo de los seres humanos es el cuidado en la salud y bienestar desde la infancia. La salud bucal en este período es importante, por lo que las visitas al odontólogo o la aplicación de mecanismos de información pueden permitir tener una buena higiene bucal. El objetivo general de esta investigación es evaluar la efectividad del programa educativo para el cuidado de la salud bucal en los niños de educación de primaria de la Escuela “Aurora Estrada” del Recinto Tres Postes durante el periodo 2018-2019. La metodología empleada para tal fin abarca la investigación corresponde al enfoque cuantitativo. Los resultados se basaron en la salud bucal del Ecuador y los resultados de la encuesta realizada a los niños de la escuela. Como conclusión se tiene que los conocimientos y el índice de higiene son altos debido a que los escolares conocen el uso de los artículos de limpieza dental y la frecuencia en que deben hacer su cuidado bucal, así como de tener conocimientos para percibir que una falta de estos puede ocasionar problemas psicosociales en su entorno, demostrando así la efectividad del programa educativo.
Consecuencias y riesgos de pacientes sometidos a varios tipos de cirugía plástica
Authors: Jiménez Cagua Álvaro Antonio , Vélez Macías María Agustina , Sánchez Saltos José Aníbal , Alcívar Macías Fernanda Vanessa
Published: February 2021

Las complicaciones anestésicas en el periodo perioperatorio en cirugía plástica son extremadamente raras, aunque pueden ser catastróficas y en ocasiones fatales. La selección adecuada y la correcta valoración preoperatoria de los pacientes son la clave para mantenerse alejado de eventos no deseados. La evaluación preanestésica es obligatoria en cada paciente y debe incluir la historia clínica, el examen físico completo y las pruebas de laboratorio de rutina y especiales en pacientes con patologías asociadas. El manejo anestésico se basa en estos resultados, el tipo de cirugía, la experiencia del anestesiólogo y el entorno operativo. La técnica anestésica puede ser local, regional o general con monitorización no invasiva estándar. Se recomienda que un anestesiólogo esté presente en todos los procedimientos de cirugía plástica. Las complicaciones suelen ser el resultado de alejarse de las pautas ya establecidas para una práctica excelente o el resultado de eventos en lugar de errores humanos. La embolia pulmonar es probablemente la complicación más temida, siendo las infecciones de tejidos blandos la complicación más frecuente en la cirugía plástica. Las complicaciones menos comunes incluyen arritmias, sobrehidratación, alergias, sangrado, necrosis cutánea, dehiscencia de heridas, daño cerebral y muerte. Los anestesiólogos, cirujanos, enfermeras y todo el personal involucrado en el cuidado de estos pacientes deben trabajar como un equipo de profesionales altamente calificados y actualizados.
Supplementary Food Therapy for the Recovery of Malnourished Children 0-59 Months: A Systematic Review
Authors:   Universitas Aisyiyah Yogyakarta, Setiyani Solikhah Eli , Utami Fitria Siswi ,   Universitas Aisyiyah Yogyakarta
Published: February 2021

ABSTRACT Background: Acute malnutrition is the highest cause of death among children under five. This is because children are a group that is vulnerable to health problems, one of which is infection. In this phase there is a very rapid growth and development in children. This problem occurs in part in low- and middle-income countries. This study aimed to review the effect of supplementary food therapy for recovery among malnourished children aged 0-59 months. Subjects and Methods: This was a scoping review using the Arksey and O’Malley framework. The framework used to identify relevant studies is Population, Intervention, Comparison, and Outcome (PICO), with a search strategy using 5 databases, namely PubMed, Science Direct, Proquest, Wiley, and Google Scholar which match the inclusion and exclusion criteria. Results: Supplementary food therapy for recovery of malnourished children 0-59 months could be done with inpatient and outpatient care using Modified Dried Skilled Milk and Coconut Oil (Modisco), Ready to use Therapeutic Food (RUTF), Soy Maize Sorghum RUTF (SMS RUTF), F 75, and F 100. The most widely used recovery supplementary food therapies are Modisco, RUTF, SMS RUTF, F75 and F100. RUTF in Indonesia has not been widely used for the therapy of malnourished children, while for F75 and F100 it has been used as a treatment but not maximally because it tastes bad so it is not liked by children. Conclusion: Several studies have examined the effectiveness of these supplementary foods, apart from being used in the hospital, they can also be given on an outpatient basis with the supervision of related health workers. Keywords: children, malnutrition, therapy, supplementary food Correspondence: Solikhah Eli Setiyani. Universitas Aisyiyah Yogyakarta, Indonesia. Email: elisetiyani01@gmail.com DOI: https://doi.org/10.26911/the7thicph.03.09
Increased the Capacity CBIA Facilitator through the Formation Agent Of Change (AoC) in the Use Antibiotics in Tanjung Gunung Village Central Bangka Regency
Authors:   School of Health Polytechnics, Ministry of Health, Pangkalpinang, Djuria Rachmawati Felani
Published: February 2021

ABSTRACT Background: The results of a personal interview with the CBIA Facilitator that after the activities of the GKSO cadre formation in 2018, there were no more activities in the village due to busyness in preparing for accreditation at the puskesmas. Therefore, it is necessary to increase the capacity of CBIA Facilitators to activate the GKSO cadres despite the busyness. In addition, it is important to enable the GKSO cadre and CBIA facilitator to bring about changes in the quality of pharmaceutical services in the community. The purpose of this study is to increase the capacity of CBIA Facilitators in providing information to the community in Tanjung Gunung Village, Central Bangka Regency, Bangka Belitung Islands Province. Subjects and Method: This was an experimental study using prestest-posttest only control group design. The study was conducted in Tanjung Gunung Village, Central Bangka Regency, Bangka Belitung Islands Province, form March-July 2019. Total of 3 pharmaceutical personnel and 24 community respondents Were selected in this study. The independent variable was capacity of CBIA Facilitators. The dependent variable was the use of antibiotic. The dara were analyzed decriptively. Results: The CBIA facilitators capacity through Agent of Change (AoC) affected the changing of the antibiotics use among community. Conclusion: The increasing of CBIA facilitators capacity through Agent of Change (AoC) also increasing the changing of the antibiotics use among community. Keywords: agent of change, antibiotics, CBIA facilitators Correspondence: Rachmawati Felani Djuria. School of Health Polytechnics, Ministry of Health, Pangkalpinang. Jl. Telaga Biru I, Desa Padang Baru, Kecamatan Pangkalan Baru, Bangka Tengah, Bangka Belitung Province. Email: felanDJ87@gmail.com. Mobile: 081995596959. DOI: https://doi.org/10.26911/the7thicph.03.17
Anemia, Motor, Language, Social Personal Developments among Children Under Two Years Old in Rural Areas, Wonosobo, Central Java, Indonesia
Authors:   Research and Development Center for Health Magelang, Central Java, Indonesia, Ashar Hadi , Kusrini Ina ,   Research and Development Center for Health Magelang, Central Java, Indonesia, Khairunnisa Marizka ,   Research and Development Center for Health Magelang, Central Java, Indonesia, Martiyana Cati ,   Research and Development Center for Health Magelang, Central Java, Indonesia
Published: February 2021

ABSTRACT Background: Anemia is a condition where the hemoglobin level in the blood is lower than normal, which can be caused by malnutrition of micronutrients. Several studies that examine anemia among children under two years old, allegedly showed a negative impact on child development. This study aimed to determine the relationship between anemia and developmental status among children under two years old. Subjects and Method: This was a cross-sectional study conducted in Wonosobo Regency, Central Java, in 2019. A total of 290 children under two years old was selected for this study. The dependent variables were motor development, language development, and social personal development. The independent variable was anemia. The data of anemia was based on the results of hemoglobin levels examination using the Hemocue technique. The measurement of developmental status was measured using Developmental Milestone Checklist II. The data were analyzed using Chi-square test. Results: Most of the children under two years old had anemia (69.3%), experienced motor development problems (27.6%); language development barrier (11.0%), and experiencing barriers to personal social development (68.3%). This study showed that anemia was not related with motor development, language development, and social personal development, and there were not statistically significant. Conclusion: There is no relationship between anemia among children under two years old and the three aspects of child development in Wonosobo Regency, Central Java, Indonesia Keywords: anemia, development, children, children under two years old Correspondence: Hadi Ashar. Research and Development Center for Health Magelang, Central Java, Indonesia. Email: hdi.gaki@gmail.com. DOI: https://doi.org/10.26911/the7thicph.03.18
Determinant Factors on Stunting Incidence among Children Age 6-24 Months, Pemalang, Central Java: A Case Study
Authors:   Faculty of Medicine, Universitas Diponegoro, Nugraheni Arwinda , Margawati Ani ,   Faculty of Medicine, Universitas Diponegoro, Wahyudi Firdaus ,   Faculty of Medicine, Universitas Diponegoro, Adespin Dea Amarilisa ,   Faculty of Medicine, Universitas Diponegoro, Hariyana Bambang ,   Faculty of Medicine, Universitas Diponegoro
Published: February 2021

ABSTRACT Background: Stunting among children under five can be caused by various factors, including inadequate food intake, characteristics of children, history of infectious diseases, family care pattern, and quality of health services. The dominant cause of stunting is different in each region. This study aimed to determinant the factors on stunting incidence among children age 6-24 months, Pemalang, Central Java. Subjects and Method: This was a case control study conducted in July 2019 in the work area of the Kebondalem Community Health Center in Pemalang, Central Java. A total of 142 stunted children aged 6-24 months were selected for this study. The dependent variable of this study was stunting. The independent variables were nutritional intake, immunization status, hygene, exclusive breastfeeding, parental education, occupation, family income, and a history of infectious diseases. Data were collected using anthropometric measurements and interviews with a questionnaire. Data were analyzed using logistic regression. Results: Mother’s occupation (OR= 0.26; 95% CI= 0.01 to 0.78; p= 0.035;), history of exclusive breastfeeding (OR= 0.07; 95% CI= 0.02 to 0.25; p= 0.001), history of infectious disease (OR= 0.008; 95%CI= 0.02-0.25; p= 0.010), Nutritional intake (OR= 9.44; 95% CI=1.88 to 47.43; p= 0.006), and they were statistically significant. Conclusion: Mother’s occupation, history of exclusive breastfeeding, history of disease infection, and nutritional intake are factors associated with the risk of stunting. Keywords: mother’s occupation, history of exclusive breastfeeding, history of disease infection, and nutritional intake, stunting Correspondence: Arwinda Nugraheni. Faculty of Medicine, Universitas Diponegoro, Yogyakarta, Indonesia. Email: arwindanugraheni@gmail.com DOI: https://doi.org/10.26911/the7thicph.03.28
The Incident of Stunting in A Rural Area
Authors:   Ngesti Waluyo Parakan Academy of Nursing Parakan, Temanggung, Putriyanti Ermayani , Kristian P Desak Putu ,   Ngesti Waluyo Parakan Academy of Nursing Parakan, Temanggung, Titin R Caecilia ,   Ngesti Waluyo Parakan Academy of Nursing Parakan, Temanggung,   Ngesti Waluyo Parakan Academy of Nursing Parakan, Temanggung
Published: February 2021

ABSTRACT Background: Stunting contributes to the increasing number of noncommunicable disease in the future and unemployment condition due to the reduced intelligence levels. In rural areas, stunting conditions are not detected properly, and their exact extent is poorly documented. This study aimed to examine the incidence of stunting in a rural area. Samples and Method: This was a descriptive survey study. The total sample used were 84 children under five years in a rural area. The main variable of this study was stunting. Data was collected using questionnaire and medical record of children’s height from maternal and child health (MCH) book in 2015 – December 2019. Data were analysed descriptively. Results: A total of 29 children (34%) were stunted. 65 children had normal weight (77%). 2 mothers were graduated from junior high school (43%). Mothers 2 mothers had a smoking history (2%), 46 mothers did not have a health insurance (55%). The income per month for 66 mothers were less than 2 million rupiah per month. 73 mothers had family member(s) who smoke in household. 55 children had birth spacing with older sibling between 6-17 years (65.5%). 21 mothers had six family members who live together in one house (25%). Conclusion: The incidence of stunting in a rural area is 34%, in which it is higher than the target of National Development Planning Agency in 2024. Keywords: incidence, stunting, children, rural area Correspondence: Ermayani Putriyanti. Ngesti Waluyo Parakan Nursing Academy. Temanggung, Central Java. Email: ermayani.putriyanti@gmail.com. Mobile: 081328054840 DOI: https://doi.org/10.26911/the7thicph.03.30
Challenge and Innovation of Long Span Bridges in China and over the World
Authors: Ge Yaojun
Published: February 2021

The challenges and achievements of long span bridges in girder, arch, cable-stayed and suspension types are briefly introduced as the background of bridging capacity innovations in China and over the world. The challenging problems encountered in girder bridges are related to extreme bending moment, PC girder excessive deflection and orthotropic steel deck cracking, and the corresponding innovative techniques include hybrid structures, corrugated steel webs or steel truss webs composite girder and steel-UHPC composite deck. The most recent achievements of arch bridges can be attributed to steel box arch ribs for maintenance convenience and life-cycle durability and concrete- filled-steel-tube arch ribs for saving steel and concrete consumption and construction costs. The current cable-stayed bridge types with spatial cable planes and closed box girder have supported to enlarged span length up to 1,400 m or 1,500 m in near future if the challenging problems of deck lateral bucking and stay cable vibration can be overcome. Suspension bridges have been identified with the most challenging problem to have super long span length, and one of three kinds of control measures, including stabilizers, slot and the combination of slot and stabilizer, has to be adopted for aerodynamic stability. For suspension bridges with multiple or at least double main spans, the most important design concept is to select the proper longitudinal bending stiffness of the central pylon.
Experimental and Numerical Studies on Post-Facture Behavior of Simply Supported Composite Twin I-Girder Bridges
Authors: Lam Heang , Lin Weiwei , Yoda Teruhiko
Published: February 2021

This study is carried out to investigate the post-fracture behavior of the composite twin I-girder bridge systems. In the experimental program, one intact specimen and one damage specimen were tested under static load with displacement control method. Different cases of fractures are performed in numerical analyses based on finite element method and nonlinear analyses. Significant reduction of system stiffness and load carrying capacity is observed in post-fracture condition. The failure modes of both intact and damage specimen are governed by the crush of the concrete slab. Nevertheless, composite twin I-girder bridge system will not collapse under dead load and be able to carry a certain level of live load. Numerical analyses for different damage conditions proved that the fracture at mid-span section is the most fracture critical location for composite twin I-girder bridge system.
Updating Life-Cycle Performance Model of Bridge based on Inspection Data
Authors: Lee Jin Hyuk , Cha Kyung Hwa , Ahn Sang Mi , Kong Jung Sik
Published: February 2021

For the bridge maintenance strategy and planning, prediction of future performance based on the current performance must be required and it is possible more rational decision-making through the higher accuracy of the prediction model. While performing a detailed inspection of the entire bridge can reduce a significant part of the uncertainty, it is impossible to reduce the uncertainty of inspection result and it is always evaluated by probability. In this study, to solve this problem, a Bayesian update method is applied to the optimal maintenance strategy in Bridge Management System (BMS) considering the uncertainty of inspection data. Also, examples of application are presented, showing the effects of inspection and updating on the bridge maintenance strategies. In this study, application possibility and availability of domestic bridge management system are evaluated by referring to the proposed method in the existing trends.
The Ordsall Chord, Manchester, UK – an overview
Authors: Duguid Brian , Whiteaker Mike
Published: February 2021

The Ordsall Chord is a new railway link which for the first time connects Manchester Piccadilly and Victorian stations, cutting rail service congestion, and allowing new rail services to be introduced. The project has been undertaken in a heavily developed city centre environment, interfacing with several important heritage assets including the Liverpool to Manchester railway, the world’s first inter-city passenger railway, dating from 1830.

The scheme comprises over 30 new and widened spans in a variety of structural forms, supporting nearly 700 m of track, including major structures spanning the River Irwell and the Trinity Way dual carriageway highway. The structures are united visually by an architectural “ribbon” concept which has significantly affected the nature and complexity of the structural designs.

Significant features of the works include the UK’s first network arch bridge; innovative structural monitoring; geometrically complex concrete arch structures; partial reconstruction of a critical heritage asset; and state-of-the-art BIM processes, including the UK’s first bridge to be built from the 3d design model without the use of conventional 2d design drawings.
Modelling Beam-Column Joints for Progressive Collapse Analysis
Authors: Salgado Rafael A. , Guner Serhan
Published: February 2021

When a reinforced concrete frame is subjected to progressive collapse due to the loss of a structural column, the surrounding elements typically experience a significant overload that may lead to their collapse. The rotational capacity of beams and, consequently, the beam-column connections is a critical factor determining the structural resiliency. Numerical models developed to assess the structural response under a progressive collapse situation must incorporate the beam-column joint response. In this study, a review of the beam-column joint modelling approaches, constitutive models, and the ease of their numerical implementation are presented. Some of these models are utilized to simulate the response of a previously-tested reinforced concrete frame. The calculated structural response parameters are compared to the experimental results, and the accuracy of each constitutive model is discussed.
Complexity Meets Craft:
Authors: Boake Terri Meyer
Published: February 2021

The past 20 years have witnessed remarkable advances in the digital design of structures. This includes the ability toimaginea diverse range of chaotic, curved and parametric structures. Where early software offered no interoperability between architectural design, engineering and fabrication software and the associated technical requirements, more recently the level of interoperability has soared. At this point Cloud based systems permit architects, engineers and steel fabricators to simultaneously create a comprehensive set of documents for structures. This level of communication has the potential to speed up the design and detailing process as well as minimize conflicts in all aspects of the construction process.

Many physical tools have been invented that are increasingly being employed to automate the processes used in the fabrication of more normative, orthogonal, structures. However, to a certain extent the actual fabrication of the steel used in complex structures has not changed appreciably over the same time. Although some computer assistance is used to cut complex shapes (particularly plate material) and control repetitive procedures such as the drilling of holes, the majority of the process has remained a craft that is carried out by the ironworker. This means that the success of the project still largely rests on the expertise of the welder and the judgment of those involved in the erection process.

As computation methods evolve at such a rate as to make much printed discussion of them rapidly out of date, this paper instead looks at the important lag between the design and fabrication of complex steel structures. Highlighted are issues of the increased importance for tight tolerances, achieving uniformity, and team coordination/communication in this yet largely craft based system and important accommodations that are required to ensure the proper fabrication and erection of Architecturally Exposed Structural Steel.
Toward Practical Modelling of Reinforced Concrete Flat Slab Systems
Authors: Goh Chong Yik M. , Hrynyk Trevor
Published: February 2021

There is increasing demand for practical modelling procedures that can be used to assess the performance of reinforced concrete (RC) structures. The numerical assessment of RC slabs at the system level typically involves one of two modelling procedures: i) models constructed with the use of three-dimensional solid finite elements, or ii) models constructed using some form of layered element, usually developed on the basis of the plane sections assumption. The use of solids has been shown to provide good structural performance estimates for RC flat plates; however, the investigation of even a single slab-column connection can be extremely costly as fine meshes consisting of many degrees of freedom are usually required. Conversely, while layered elements are computationally more efficient, they typically provide extremely coarse estimates of the out-of- plane (through-thickness) shear response and generally cannot capture the influence of disturbances developed in slab-column connection regions.

This paper presents the application of an alternative RC slab system modelling procedure. Low-cost layered thick-shell finite elements that can adequately model through-thickness shearing effects were used to capture global slab system behaviour and a simple sectional analysis modification procedure was used to accommodate strength enhancements attributed to slab disturbances. Employing the formulations of the Disturbed Stress Field Model (DSFM), the thick-shell finite element analysis procedure was used to model the response of RC slab-column connections under concentric shear loading conditions. Shell element-based numerical responses were compared with those obtained using more conventional modelling procedures (e.g., solid continuum), and were contrasted with experimental data. Further, the validated RC slab modelling procedure was used to analyze the response of a slab subsystem test available in the current database of experimental literature, and was shown to provide good agreement with test results.
Repair, Strengthening and Upgrading of Steel Bridges in The Netherlands
Authors: Snijder H. H. (Bert) , Hesselink B. H. (Bert)
Published: February 2021

After World War II, many steel bridges were designed and built in The Netherlands. Many of these bridges are now of a substantial age and were designed for static and fatigue loading less severe than eventually present during their lifetime. Many of these bridges now show (fatigue) damage. Depending on the nature of the damage, these bridges can either be replaced, or a reinforcing substructure can be added, or the visible damage can be repaired and the bridge can be locally strengthened. In many cases, it has to be shown that the bridge is fit for purpose for future use, meaning that upgrading may be necessary. These bridges are now being reassessed and any possible conservatism in these assessments needs to be excluded to avoid unnecessary strengthening. The paper gives practical examples of repair, strengthening and upgrading techniques for steel bridges.
A Technique for Strengthening Existing Continuous Non-Composite Steel Girder Bridges Using Post-Installed Shear Connectors and Inelastic Moment Redistribution
Authors: Ghiami Azad Amir Rez , Kreitman Kerry , Engelhardt Michael , Helwig Todd , Williamson Eric
Published: February 2021

Many older bridges are constructed with floor systems consisting of a non-composite concrete deck over steel girders. A potentially economical method for strengthening these bridges is to develop composite action by attaching the existing concrete deck to the steel beams using post-installed shear connectors. The current paper discusses this method based on the findings from a large-scale research study aimed at strengthening existing non- composite continuous steel girder bridges. The results of this research indicate that post- installed shear connectors are a feasible and efficient method of extending the useful service life of a non-composite steel girder bridge. Increases of more than 60-percent in the ultimate strength of the bridge girders tested in this study were attained by strengthening to a composite ratio of only 30-percent. The test program also exhibited excellent fatigue resistance for the post-installed shear connectors.
Live Load Distribution Factors for a Lightweight Movable Bridge Deck System
Authors: Baghi Hadi , Menkulasi Fatmir , Parker Jacob
Published: February 2021

Louisiana has approximately 160 movable bridges, mostly in the southern part of the state. The typical deck systems in these movable bridges are steel grids. Records show that steel grids have had maintenance issues. A precast lightweight concrete deck system for Louisiana’s movable bridges is presented. The deck configuration features a multi-rib T-beam configuration. Live load distribution factors (LLDFs) for flexure and shear are quantified so that the deck system can be designed using the traditional beam line analysis method. Several nonlinear finite element analyses were conducted to quantify worst case LLDFs for interior and exterior ribs. A variety of load positions and span configurations are examined. LLDFs for moment and shear vary from 0.63 to 0.87, and from 0.64 to 0.86, respectively. The LLDFs for flexure and shear provided in this paper offer a practical approach for designing this new deck system for movable bridges.
Numerical Evaluation of Moment Live Load Distribution Factors in NEXT D Beam Bridge
Authors: Semendary Ali A. , Jawdhari Akram R.
Published: February 2021

NEXT D beam bridges have often been preferred for short and medium span bridges due to ease and speed of construction, and elimination of the intermediate diaphragms. The NEXT D beam is the integral full depth flange that also acts as the structural bridge deck. However, there is a concern about the live load distribution factors (LLDFs) for this type of bridges. There are no design specifications addressed in the current AASHTO Load and Resistance Factor Design (LRFD) Specifications. A conservative approach is suggested by the PCI Northeast Bridge Technical Committee to calculate the live load distribution factors. In this research, a three dimensional (3D) finite element (FE) model was created using ABAQUS software for a 3 m (10 ft) wide single NEXT D beam and verified with manual calculations based on AASHTO LRFD specifications. After verification, the model was applied to a typical bridge, comprised of NEXT D beams, and used to calculate the LLDFs. The results were compared with the LLDFs calculated using AASHTO LRFD and PCI Northeast recommendations. FE model results compared well with the manual calculations, indicating that the model can be used to predict the LLDFs of the NEXT D beam bridge. Furthermore, LLDFs for interior beams are: 0.74 from the FE model, 0.81 from the AASHTO LRFD computations, and 1.04 from the PCI Northeast calculations. While for exterior beams, LLDFs are: 0.79 from the FE model, 1.03 from the AASHTO LRFD computations, and 0.96 from the PCI Northeast calculations.
Ultimate load of cylindrically curved panels under uniform compression at straight edge and the influence of curvature
Authors: Guo Hui , Zeng Zhibin , Lu Xiaoguang , Ju Xiaochen , Zhao Xinxin
Published: February 2021

Curved panels are widely used in modern novel steel bridges and buildings. Stability shall be considered for these structures under compressive loads. While it still has many challenges on how to consider stability since there are no guidelines in specifications. In this paper, ultimate load of the cylindrically curved panels were studied. First, accuracy of numerical model was verified by theory and model test. Then the influence of curvature on ultimate load at the straight edge of curved panel was studied. Results showed that the deformation of curved panel was obvious in the direction perpendicular to the panel. The position of maximum deformation was located near the central region and perpendicular to the curved panel. Ultimate load of curved panel is smaller than the straight one. And the ultimate load decreases as the curvature increases with a linear relationship between the reduction factor of local stability and the curvature.
Conceptual Design of Salmon River Replacement Bridge
Authors: Rebel C. P. (Ken) , Singh Raj , Abercromby Pia
Published: February 2021

Replacing an existing narrow two-lane truss bridge constructed in 1954 with a wider modern day girder bridge while keeping the existing roadway alignment and maintaining two lanes of traffic throughout the construction period presents some interesting challenges. The Salmon River Bridge is a 180’ (54.9 m) long single span steel Pratt truss structure located approximately 27 km north of the City of Prince George on Highway 97. McElhanney reviewed a number of conceptual bridge replacement designs including single span and multi-span configurations utilizing steel and/or concrete structures and reviewed existing, upstream and downstream road alignments. After considering environmental impacts, constructability, detour requirements and the need for under bridge walkways it was decided to design and construct a new 66.5 m long single span bridge on the existing roadway alignment utilizing steel girders and a concrete to-grade deck.
Opening effect on punching shear strength of RC slabs
Authors: Balomenos Georgios , Genikomsou Aikaterini , Polak Marianna
Published: February 2021

Punching shear failure can happen in reinforced concrete flat slabs due to the development of high shear stresses in the slab-column connection area. These shear stresses are increased when openings are created, since the presence of openings reduce the concrete area that sustains the shear stresses. In this paper, finite element analysis (FEA) with the damaged plasticity model for concrete in ABAQUS is performed to simulate the opening effect in reinforced concrete slabs without shear reinforcement. A previously tested and analyzed interior slab-column connections is considered. The effect of the location and the size of the opening on the punching shear resistance are investigated. The punching shear capacity of the analyzed specimens is calculated using the equations of two current design provisions for punching shear (ACI 318-14, Eurocode2-2004) and compared with the numerical results. A probabilistic analysis using Monte Carlo simulation for both design codes is considered. Finally, fragility analysis is performed in order to estimate the probability of the estimated punching shear resistance related with the opening size and distance.‌‌
Punching/Shear Strength of a Full-scale Tested Bridge Deck Slab
Authors: Shu Jiangpeng , Plos Mario , Nilenius Filip , Zandi Kamyab , Bagge Niklas , Johansson Morgan
Published: February 2021

For reinforced concrete (RC) slabs without shear reinforcement, shear and punching can be the governing failure mode at ultimate limit state if subjected to large concentrated loads. Punching of RC slabs without shear reinforcement has been a challenging problem in assessment based on current standards. To examine a previously developed enhanced analysis approach, this study was conducted by applying continuum FE analyses to a 55-year old RC bridge deck slab subjected to concentrated loads near the main girder in a field failure test. The influence of parameters such as boundary conditions, location of concentrated loads and shear force distribution were investigated.
Wind Response of the New Varodd Bridge Balanced Cantilever
Authors: Svendsen Martin N. , Kolstrøm Arne Øyvind , Møller Randi N.
Published: February 2021

The New Varodd Bridge is a 655m concrete girder bridge with four main spans with a maximum length of 260m. The bridge will be located in a very narrow position between the existing Varodd suspension bridge on the southern side and the existing Varodd girder bridge on the northern side. The new bridge will be constructed as a balanced cantilever with a connection to the existing girder bridge that connects the bridges in transverse displacements but not in vertical displacements. During this phase the bridge is very sensitive to wind effects. An additional complication lies in the proximity of the existing bridges which highly impact the flow around the new structure. This paper addresses the coverage of these aspects, through a combination of wind response calculations in both frequency domain and time domain, as well as wind tunnel tests performed on a 1:160 scale aeroelastic model of the balanced cantilever.
The New Champlain Bridge Corridor Project – Needs, Owner
Authors: Mailhot Guy
Published: February 2021

A rapidly deteriorating condition of the existing Champlain Bridge in Montreal, led the Government of Canada to accelerate its replacement and ultimately award a $3.98 billion CDN contract to Signature on the Saint Lawrence Group to deliver a new replacement crossing.

Entailing a 3.4 km long structure over the St. Lawrence River with some 193,000 m2 of new deck construction, the works represent one of the largest infrastructure projects currently underway in North America and will produce Canada’s biggest bridge.

The first of six related papers submitted to this symposium, this paper explains the need for an accelerated schedule, describes the delivery method used, summarizes the imposed requirements to ensure delivery of a highly durable structure (125-year design life) and key architectural features of the bridge required to endow Montreal with an elegant world class transportation infrastructure.
Numerical Study of the Seismic Behaviour of Variable Friction Base Isolation Systems
Authors: Calvi Paolo M. , Timsina Sandip
Published: February 2021

Variable Friction Systems (VFS) have been recently proposed as potential alternatives to traditional friction devices. VFS come with an extra design “degree of freedom”, in the form of coexisting multiple friction coefficients across the sliding surface, so that the properties of the base isolators can be adjusted to achieve enhanced seismic performance. In particular, the principal benefit of VFS is their capacity of dissipating a larger amount of energy with respect to their constant-friction counterparts, reducing the displacement demand on the system, and the lateral forces and accelerations transmitted to the isolated structure.

This paper presents the results of more than 450,000 non-linear time history analyses, illustrating key differences in the response of VFS as a function of the systems’ properties and showing that generic VFS can be capable of high seismic performance.
Vibration control of footbridges under pedestrian loading using tuned mass damper systems with eddy current damper technology
Authors: Saige David , Engelhardt Jürgen , Katz Sebastian
Published: February 2021

Footbridges are prone to vibrations induced by pedestrians depending on the bridge`s natural frequencies. Well-known measures to increase the structural damping of a footbridge and hence control the risk of vibrations are Tuned Mass Dampers (TMD). One of the main parameters defining the overall effectiveness of a TMD is its damping mechanism; for this purpose eddy current dampers are an innovative solution, which can improve TMD performance significantly.

This paper describes the design of an eddy current damper as part of a passive tuned mass damper. First, the theoretical potential is analysed analytically. A detailed discussion on the optimization of TMD parameters combined with the characteristics of eddy current dampers shows its advantages. In the second part a TMD construction using an eddy current damper is designed based on a case study of a footbridge.
The development of timber as a construction material for bridges in Norway
Authors: Veie Johannes , Stensby Trond Arne , Dyken Tormod , Aartun Yngve
Published: February 2021

Throughout the nineties, a new generation of wooden bridges were born in Norway. This was the result of mixing traditional knowledge about the use of wood with the use of modern glulam technology and innovative solutions regarding connections. In addition, the use of preservatives in combination with constructive protection made the bridges more durable. In the past two decades there has been a continuous development of bridge technology. It is not an important target to use as much timber as possible, but rather to exploit the best characteristics of every material, including steel and concrete. This has led to that we can push the limits of the use of this environmentally friendly material. This paper shows some examples of bridges that have been built and presents a record-breaking bridge that may be the next step in the timber bridge era
Case Study: University of British Columbia’s 18-storey TallWood House at Brock Commons
Authors: Fast Paul , Jackson Robert
Published: February 2021

The TallWood House at Brock Commons is an 18-storey mass timber hybrid student residence under construction at the University of British Columbia in Vancouver, Canada. When completed in the spring of 2017 it will be 53m high – the tallest contemporary mass timber hybrid building in the world. Structural engineers at Fast + Epp collaborated with Acton Ostry Architects and Hermann Kaufmann Architekten. This paper will outline some of the unique structural engineering challenges associated with this mass timber building and the design strategies used to overcome them. Specific topics include two-way point supported CLT floor slabs, axial column shortening, CLT diaphragm design, tolerances, as well as dynamic wind induced vibrations. It will also review the project’s pre-fabrication process, on-site construction sequencing, and lessons learned.
Effect of Regrinding on the Edge Strength of Tempered Glass
Authors: Lohr Katharina , Weller Bernhard
Published: February 2021

Laminated glass can have an edge displacement of the individual glass panes resulting from the lamination process. With regard to visible or exposed edges, this displacement reduces the optical quality of the glass component. The regrinding of the edge after lamination compensates the displacement and thus creates a highly transparent surface. However, regrinding tempered glass leads to a reduction of the compression zone near the edge and bears the risk of reducing the load‐ bearing capacity. The degree of this reduction was experimentally determined and evaluated at the Institute of Building Construction with the aid of both single‐glass panes and structural component tests.
Fatigue damage evaluation using S-N curves obtained by different data fitting methods
Authors: Leonetti Davide , Hashemi Bahman , Allaix Diego , Maljaars Johan
Published: February 2021

This paper investigates the differences in the predicted fatigue life of transverse butt weld joints and cover-plated beams considering statistically based fitting methods on fatigue test data and comparing the results with the S-N relation proposed in international standards. The test data fitting are performed by employing the Least Square Method (LSM) and the Maximum Likelihood Method (MLM) taking into account the contribution of the runouts. The Mean curve, the characteristic curve and the design curve have been derived. In order to consider the effect of Variable Amplitude loading, the S-N curves have been extended and the fatigue damage according to the Palmgren- Miner cumulative damage rule is evaluated for a load spectrum that follows a Rayleigh distribution. The results have been compared and discussed together with a Linear Elastic Fracture Mechanics (LEFM) based fatigue prediction.
Creative Construction Method for an Attractive Tied Arch
Authors: Hamersley Bruce , Wu William , O'Reilly James
Published: February 2021

The City of Chilliwack is replacing an important bridge over the Vedder River using the design build project delivery model. The winning design was an attractive 60m twin tied steel arch bridge with steel hanger rods in a “ray” arrangement. The longitudinal tie girders for the arch is a steel box section which connect the ends of the pipe arch ribs, and support transverse floor beams. The tie girders are made continuous through a 20m south side span. In-river works were undesirable due to fisheries windows schedule limitations. Launching was therefore chosen for the erection method. This presented unique challenges for an arch due to high abutment reactions on the underside of the tie girders during the launch. A temporary kingpost design was developed to support the midspan of the arch during the launch. The continuous south side span tie girders will act as a launching nose. The kingpost will also be used to support the old truss bridge during demolition.