Richard Shaun Walls, Rodney Eksteen, Charles Kahanji and Antonio Cicione
Informal settlements are inherently unstructured in nature, lack adequate services, regularly have high population densities and can experience social problems. Thus, fires can…
Abstract
Purpose
Informal settlements are inherently unstructured in nature, lack adequate services, regularly have high population densities and can experience social problems. Thus, fires can easily propagate rapidly through such areas, leaving thousands homeless in a single fire. The purpose of this paper is to present an appraisal of various interventions and strategies to improve fire safety in informal settlements in South Africa (globally, similar settlements are known as slums, ghettos, favelas, shantytowns, etc.), considering aspects of both technical suitability and social suitability.
Design/methodology/approach
This paper focusses on three specific aspects: ignition risk management, active fire protection interventions and passive fire protection interventions. These are presented within a framework to outline how they may mitigate the impact of fires.
Findings
Often “solutions” proposed to improve fire safety either lack a sound engineering basis, thus becoming technically inefficient, or do not consider social circumstances and community responses in settlements, thereby becoming practically, socially or economically unsuitable. It must be understood that there is no “quick fix” to this significant problem, but rather a combination of interventions can improve fire safety in general. A broad understanding of the various options available is essential when addressing this problem, which this paper seeks to provide.
Practical implications
This paper seeks to provide an overview to guide policymakers and organisations by illustrating both the advantages/benefits and disadvantages/challenges of the interventions and strategies currently being rolled out, as well as potential alternatives.
Originality/value
A broad but succinct appraisal is provided that gives insight and direction for improving fire safety in informal settlements. It is hoped that the challenges associated with the fire safety interventions discussed can be addressed and improved over time.
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Richard Walls, Celeste Viljoen and Hennie de Clercq
This paper aims to provide a parametric investigation into the behaviour of steel, concrete and composite beams exposed to fire. This investigation gives insight into the…
Abstract
Purpose
This paper aims to provide a parametric investigation into the behaviour of steel, concrete and composite beams exposed to fire. This investigation gives insight into the structural behaviour of elements experiencing thermal and mechanical loading illustrating reasons for observed global structural behaviour, and identifying how selected design parameters influence results obtained. Non-linear heating/thermal bowing behaviour is specifically considered.
Design/methodology/approach
Cross-sectional stresses and strains, resultant thermal forces, bending stiffness, axial stiffness and deflections are plotted for beams subjected to different fire regimes or input values. The impact of changes in input parameters on beam section properties is illustrated. Unusual structural responses, localised effects and general trends are identified in relation to variations in thermal gradients, concrete tensile capacity, standard fire exposure time and the assumed concrete flange widths of composite beams.
Findings
Stress-strain plots highlighting cross-sectional structural behaviour, trends in beam properties and the influence of design parameters are provided. Some counter-intuitive behaviour is explained, such as increased member stiffness being offset by increased thermal effects, leading to this parameter having negligible impact on global behaviour but a significant effect on local stresses and strains. Increased concrete strengths may lead to increased thermal deformations, whilst the inclusion of concrete tensile capacity typically has a minimal influence.
Research limitations/implications
The research focusses on cross-sectional properties, although results generated illustrate how global behaviour is affected.
Practical implications
Design engineers are made aware of how selected input values influence predicted structural response. Also, localised stress and strain behaviour relative to imposed loads and thermal effects can be identified.
Originality/value
This paper provides novel insight into the (sometimes counter-intuitive) behaviour of beams exposed to fire, highlighting trends and the influence of important input parameters on predicted response.
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Hendrig Marx and Richard Walls
The Southern African Institute of Steel Construction has developed a novel cellular beam structure (CBS) for multi-storey buildings that is entirely devoid of concrete. Channel…
Abstract
Purpose
The Southern African Institute of Steel Construction has developed a novel cellular beam structure (CBS) for multi-storey buildings that is entirely devoid of concrete. Channel sections between the cellular beams support a complex sandwich flooring system, which contains a fire-resistant ceiling board, metal sheeting, an interior fibre-cement board and an access-flooring system. As for all structures, the CBS requires a fire rating. This paper aims to investigate the thermal behaviour of the CBS using numerical modelling and experimental fire testing, as it has a unique setup.
Design/methodology/approach
Experimental fire tests on the flooring system were conducted to validate finite element models, which were developed in ABAQUS. These models were then extended to include floor beams and the structural steelwork.
Findings
Good correlations were found between the experimental and numerical results, with temperature variations typically in the range of 0-5%, although with localised differences of up to 20%. This allowed larger finite element models, representing the sandwich floor system of the CBS, to be developed and analysed. A 1-hour rating can be obtained by the system in terms of insulation and integrity requirements.
Practical implications
The CBS allows for more economical steel structures, due to the rapid construction of its modular panels. A suitable fire resistance will ensure the safety of the occupants and prevent major structural damage. Steelwork and flooring temperatures are determined which has allowed for global structural analyses to be carried out.
Originality/value
The originality of this study lies in thermal analysis and testing of a new cellular beam flooring system, through determining behaviour in fire, along with beam temperatures.
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David Rush, Greg Bankoff, Sarah-Jane Cooper-Knock, Lesley Gibson, Laura Hirst, Steve Jordan, Graham Spinardi, John Twigg and Richard Shaun Walls
Globally, over 95% of fire related deaths and injuries occur in low- and middle-income countries. Within informal settlements, the risk of fire resulting in injury or death is…
Abstract
Purpose
Globally, over 95% of fire related deaths and injuries occur in low- and middle-income countries. Within informal settlements, the risk of fire resulting in injury or death is particularly high. This paper examines fire risks in informal settlements in New Delhi and Cape Town, and tented informal settlements in Lebanon.
Design/methodology/approach
Our analysis draws on primary sources, secondary literature, statistical data and qualitative interviews.
Findings
The distribution of fire risk across urban societies is a fundamentally political issue. Residential fire risk can be tackled by accessible, affordable, safety-compliant housing. That said, important interim measures can be taken to mitigate fire risk. Some of the risks requiring attention are similar across our case studies, driven by high population densities; flammable housing materials; unreliable or inaccessible access to safe power sources; and – in the case of Cape Town and New Delhi particularly – the inability of fire services to reach sites of fire. However, these common risks are embedded in distinct social, economic and political contexts that must be placed at the center of any intervention. Interventions must also be aware that the risk of fire is not spread evenly within informal settlements, intersecting as it does with factors like gender, age, health and disability.
Originality/value
Informal settlement fires have been under-studied to date. The studies that do exist tend to operate within disciplinary silos. This paper represents an important interdisciplinary approach to fire within informal settlements, which grounds technical data, modeling and experiments in political, social and economic realities.
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Richard Walls, Celeste Viljoen, Hennie de Clercq and Charles Clifton
This paper aims to present a reliability analysis of the slab panel method (SPM) for the design of composite steel floors in severe fires. Rather than seeking to accurately define…
Abstract
Purpose
This paper aims to present a reliability analysis of the slab panel method (SPM) for the design of composite steel floors in severe fires. Rather than seeking to accurately define failure levels, this paper highlights areas of uncertainty in design and their effect on design results, whilst providing approximate reliability levels.
Design/methodology/approach
A Monte Carlo simulation has been conducted using the SPM design procedure to produce probability density functions of floor capacity for various floor layouts. Statistical input variables were obtained from the literature. Different configurations, geometries and fire severities are included to demonstrate how predicted floor capacities are influenced.
Findings
From the research presented, it is clear that the predicted reliability of SPM systems varies relative to a large number of criteria, but especially parameters related to fire loading. Predicted capacities are shown to be conservative compared to results of furnace and large-scale natural fire tests, which exhibit higher fire resistance. Due to distinct fire hazard categories with associated input values, there are step discontinuities in capacity graphs.
Originality/value
Limited research has been done to date on the reliability of structures in fire as discussed in this paper. It is important to verify the reliability levels of systems to ensure that partial and global factors of safety are adequate. Monte Carlo simulations are shown to be effective for calculating the average floor capacities and associated standard deviations. The presentation of probability density functions for composite floors in severe fires is novel.
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Saeideh Saeidi and Richard Wall
Severe mental illness affects a significant number of people and, if left untreated, leads to poor quality of life and disability. Many of the aspirations proposed for new models…
Abstract
Purpose
Severe mental illness affects a significant number of people and, if left untreated, leads to poor quality of life and disability. Many of the aspirations proposed for new models of care assert that better preventative services, closer integration between professionals, and increased access to cognitive behavioural therapy in primary care will bring substantial benefits and improved outcomes. The purpose of this paper is to explore the benefits of integrating mental health services into primary care, and improving collaboration between secondary services and primary care. There is a transition underway in healthcare whereby a focus on illness is being supplemented with, or refocused towards achieving better patient well-being. New approaches to service provision are being proposed that: focuses on more holistic outcomes; integrates services around the user; and employs innovative system techniques to incentivise professional and organisational collaboration. Such a transition must be inclusive of those with mental health needs managed in primary care and for those people with serious mental illness in secondary care.
Design/methodology/approach
This paper discusses the issues of professional collaboration and the need to provide mental healthcare in a continuous and coordinated manner and; how this may improve timely access to treatment, early diagnosis and intervention. Importantly, it is essential to consider the limitations and reality of recent integration initiatives, and to consider where the true benefit of better integrating mental health into a more collaborative system may lie.
Findings
Identifying and addressing issues of parity is likely to call for a new approach to service provision that: focuses on outcomes; co-designs services integrated around the user; and employs innovative contracting techniques to incentivise provider integration.
Practical implications
There is a transition underway in healthcare whereby a focus on illness is being supplemented with or refocused towards working towards wellness. Such a transition requires primary care mental health services to be provided in a continuous and coordinated manner in order to meet the health needs of people with serious mental illness.
Originality/value
It discusses the issues of professional collaboration and how this may improve timely access to treatment, early diagnosis and intervention. It is essential to consider the limitations and reality of recent integration initiatives, and to consider where the true benefit may lie.
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Historians have long understood that transforming people into property was the defining characteristic of Atlantic World slavery. This chapter examines litigation in British…
Abstract
Historians have long understood that transforming people into property was the defining characteristic of Atlantic World slavery. This chapter examines litigation in British colonial Vice Admiralty Courts in order to show how English legal categories and procedures facilitated this process of dehumanization. In colonies where people were classified as chattel property, litigants transformed local Vice Admiralty Courts into slave courts by analogizing human beings to ships and cargo. Doing so made sound economic sense from their perspective; it gave colonists instant access to an early modern English legal system that was centered on procedures and categories. But for people of African descent, it had decidedly negative consequences. Indeed, when colonists treated slaves as property, they helped to create a world in which Africans were not just like things, they were things. Through the very act of categorization, they rendered factual what had been a mere supposition: that Africans were less than human.
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This case exposes students to predictive analytics as applied to discrete events with logistic regression. The VP of customer services for a successful start-up wants to…
Abstract
This case exposes students to predictive analytics as applied to discrete events with logistic regression. The VP of customer services for a successful start-up wants to proactively identify customers most likely to cancel services or “churn.” He assigns the task to one of his associates and provides him with data on customer behavior and his intuition about what drives churn. The associate must generate a list of the customers most likely to churn and the top three reasons for that likelihood.
Details
![University of Virginia Darden School Foundation](/insight/static/img/university-of-virginia-darden-school-foundation-logo.png)
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This case is suitable for graduate-level quantitative analysis, business and government, environment and sustainability, and global economics courses. Students must consider the…
Abstract
This case is suitable for graduate-level quantitative analysis, business and government, environment and sustainability, and global economics courses. Students must consider the tradeoffs between continuing to run an old coal-burning plant and purchasing emissions allowances (EAs) versus upgrading to emissions-reducing wet or dry scrubbers. Reducing emissions creates the possibility of selling the plant's surplus EAs (which are likely to increase in price). Choosing a wet or dry scrubber requires considering installation cost and construction time, variable cost, and SO2 removal efficiency. Ideally, the investment should pay back over time, but management believes some net investment could also be justified. For that, however, complete analyses from both economic and environmental perspectives are required. A supplemental spreadsheet is available to accompany the case (UVA-QA-0726X).
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![University of Virginia Darden School Foundation](/insight/static/img/university-of-virginia-darden-school-foundation-logo.png)