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The paper aims to deal with the enhancement of a simplified method for the design of concrete columns subject to fire toward applications on circular and tubular cross-sections. The original zone method, developed by Hertz as a plastic design method, has been extended by Achenbach for the use as a nonlinear method. This proposed extended zone method (EZM) is verified by checking the theoretical background and is successfully validated by the recalculation of laboratory tests.

The zone method assumes a reduction of a cross-section by a “damaged” zone. The remaining area is modeled with the constant, temperature-dependent material properties. The equations for the calculation of the damaged zone to model the loss of cross-section resistance or stiffness are derived. The proposed equations are validated by the recalculation of laboratory test and compared to the results of the advanced method (AM).

It can be shown that the EZM is suitable for the check of the fire resistance of circular concrete columns and leads to a safe and economic design. The method provides a suitable alternative to more sophisticated AM. The further extension toward tubular spun columns is discussed und is the object of the ongoing research.

Presented enhancement extends the range of applications of the EZMs toward circular and tubular cross sections, which has previously not been examined.

The purpose of this paper is to develop a method suitable for the design of reinforced concrete columns subjected to a standard fire.

The Zone Method – a ’simplified calculation method” included in Eurocode 2 – has been developed by Hertz as a manual calculation scheme for the check of fire resistance of concrete sections. The basic idea is to disregard the thermal strains and to calculate the resistance of a cross-section by reducing the concrete cross-section by a “damaged zone”. It is assumed that all fibers can reach their ultimate, temperature dependent strength. Therefore, it is a plastic concept; the information on the state of strain is lost. The calculation of curvatures and deflections is thus only possible by making further assumptions. Extensions of the zone method toward a general calculation method, suitable for the implementation in commercial design software and using the temperature dependent stress–strain curves of the Advanced Calculation Method, have been developed in Germany. The extension by Cyllok and Achenbach is presented in detail. The necessary assumptions of the Zone Method are reviewed, and an improved proposal for the consideration of the reinforcement in this extended Zone Method is presented.

The principles and assumptions of the Zone Method proposed by Hertz can be validated.

An extension of the Zone Method suitable for the implementation in design software is proposed.

The design check regarding the fire resistance of concrete slabs can be easily performed using tabulated values. These tables are based on experimental results, but the level of safety, which is obtained by this approach, is not known. On the other hand, performance-based methods are more accepted, but require a target reliability as performance criterion. Hence, there is a need for calibration of the performance-based methods using the results of the “traditional” descriptive approach.

The calibration is performed for a single span concrete slab, where the axis distance of the reinforcement is chosen according to Eurocode 2 for a defined fire rating. A “standard” compartment is selected to cover typical fields of application. The opening factor is considered as parameter to obtain the maximum peak temperatures in the compartment. A Monte Carlo simulation, in combination with a response surface method, is set up to calculate the probabilities of failure.

The results indicate that the calculated reliability index for a standard is within the range, which has been used for the derivation of safety and combination factors in the Eurocodes. It can be observed that members designed for a fire rating R90 have a significant increase in the structural safety for natural fires compared to a design for a fire rating R30.

The level of safety, which is obtained by a design based on tabulated values, is quantified for concrete slabs. The results are a necessary input for the calibration of performance-based methods and could stimulate discussions among scientists and building authorities.

This paper aims to investigate the state of the art for the reliability evaluation of reinforced concrete beams in a fire situation. Special emphasis is placed on addressing which parameters were considered probabilistically or deterministically, the prescribed probabilistic models for the assumed stochastic variables, the treatment of the heat transfer mechanism, the quantification of the structural fire performance and the assumed target reliability levels.

Research papers were identified through a search on the Web of Science, Google Scholar and detailed searches within the journals Journal of Structural Fire Engineering, Fire Technology and Fire Safety Journal, supplemented with references known by the authors.

Considering the state-of-the-art review, gaps in the literature are identified related to (1) the probabilistic evaluation of shear capacity for standard fires and parametric fires, and bending capacity for parametric fires, (2) the absence of reference fragility curves for immediate design application/code calibration and (3) the specification of target safety levels for reliability-based design.

The lack of research papers gathering studies on the reliability of reinforced concrete beams in fire situation makes it difficult to further develop research in the area. The value of this work lies precisely in the collection of the basic information, making it possible to identify gaps to be addressed in future research and the suggestion of a research framework.

This article examines how contact with the police led to the death of Michael Brown (an unarmed 18-year-old Black teenager from Ferguson, Missouri, who was shot and killed during an altercation with a police officer). And, how Darren Wilson (the White police officer from the Ferguson Police Department who shot and killed Michael Brown) was portrayed in mainstream newspaper articles covering the story of Brown’s death.

Using both frame analysis and Hall’s framework of discursive domains for organizing and making sense of events in social life, we analyzed news coverage of Brown in three of the top circulating daily newspapers in the US: The New York Times, Los Angeles Times, and The Washington Post. The Lexis Nexis database was used to retrieve a set of newspapers using the search term “Michael Brown.” Articles from the three leading newspapers were collected from the day the event occurred, August 9, 2014, through the end of the year, December 31, 2014.

The news articles used in this study were mostly written with an episodic frame. The articles presenting the socioeconomic background of Brown and Wilson were described as profiles on each individual and the neighborhood they came from, rather than a discussion about where they fell on the economic structure of this country and the larger, upstream forces that might influence those positions. The feelings and attitudes of the reader are also likely to be influenced by details included in the articles and how they were presented.

The findings contribute to the broader literature looking at the relationships between police and Black communities. Public health can play a role in advocating and facilitating programs that build better linkages between police and community. The public health field can take a leadership role in holding the news media accountable when they are engaging in frenetic inaction. Only by having difficult and challenging conversations that examines the upstream causes of violence and deaths like Brown’s, can we make progress in preventing them.

This study aimed to examine how Medical Expenditure Panel Survey (MEPS) data have been used to support scientific discoveries in biomedical and health sciences, and provide insight to researchers who are interested in using MEPS regarding collaborations and dissemination of research output.

A bibliometric approach was used to systematically examine the publications that used MEPS data and were indexed by PubMed and Web of Science (WoS). Microsoft Excel and bibliometric tools (WoS and VOSviewer) were utilized for quantitative and bibliometric network analysis. The measures were investigated on the total number of publications by year, research categories, source journals, other datasets/databases co-used with MEPS, funding sources, collaboration patterns, and research topics.

A total of 1,953 eligible publications were included in this study with the numbers growing significantly over time. MEPS data were primarily used in healthcare services, public environmental and occupational health research. The journals that published the most papers using MEPS were all in the healthcare research area. Twenty-four other databases were found to be used along with MEPS. Over 3,200 researchers from 1,074 institutions in 25 countries have contributed to the publications. Research funding was supported from federal, private, local, and international agencies. Three clusters of research topics were identified among 235 key terms extracted from titles and abstracts.

Our results illustrated the broad landscape of the research efforts that MEPS data have supported and substantiated the value of AHRQ's effort of providing MEPS to the public.

The purpose of this paper is to describe non-specialised, group-based interventions in displaced populations from reviewed literature, and to explore their outcomes.

A literature review was conducted using the PubMed database, Web of Science, The Cochrane Library of Systematic Reviews, and defined “grey literature”. Characteristics of the interventions were summarised into a table under key categories such as targeted persons, study setting, level of evidence, outcome measures, assessment tools used and summary of results.

In total, 11 articles were identified stemming from nine separate interventions. Three of these were considered level 1 evidence as they were randomised controlled trials. The described interventions were markedly heterogeneous in nature and produced diverse findings. There were noted methodological issues in the majority of interventions reviewed.

This original research has demonstrated clear need for research that uses robust methodology accounting for the complex and challenging nature of this context.