David Lange

• RISE Research Institutes of Sweden

This paper seeks to provide key fundamental knowledge underpinning the use of self-extinction principles as part of a design framework for buildings with engineered mass timber structures. The results from six compartment fire experiments in a cross-laminated timber (CLT) enclosure with different ratios of exposed timber are presented and analyzed...

The response of structures to fire is predominantly articulated in terms of the time of exposure to a nominal fire, although it is widely recognized that this time of exposure is poorly correlated to structural response to fire. This often results in a sub-optimal design of buildings for fire. This can be addressed by adopting a performance-based d...

As timber is combustible, the inherent fuel load of a mass or engineered timber structure can significantly impact compartment fire dynamics compared to a non-combustible structure. Recently, large-scale open-plan testing reaffirmed these phenomena in compartments with exposed timber, with a rapid transition to fully developed fire following the ig...

Many design regulations around the globe rely on member deflection as a governing criterion for resistance assessment in fire. The deflection evaluation in fire is generally achieved by conducting expensive experiments or computationally expensive finite-element analyses. This often restricts practicing engineers from using robust performance-based...

Recent large-scale open-plan testing has highlighted the rapid change in fire dynamics within the compartment following the ignition of an exposed timber ceiling. There is no standard approach, nor is there any significant research that has been undertaken to understand what impact inverting an exposed surface to a ceiling orientation has on the ti...

A suitably large number of simulations are expected to be carried out to provide a reliable estimate of structural risk against fire while employing a popular Monte Carlo procedure. It has been observed by many researchers in the earthquake engineering field that the use of an efficient intensity measure (IM) reduces the dispersion in the structura...

A series of large-scale experiments has been conducted on under-ventilated mass timber room compartments with kerosene pool fires. To characterise the role of exposed timber walls on the fully-developed phase of the fire, the exposed surface area of mass timber was varied between experiments. Experiments with all timber surfaces protected were comp...

Green roofs are increasingly incorporated into cities worldwide due to their key role in solving urban problems like mitigating heat islands, facilitating ecology, improving mental health, and controlling stormwater. The implementation of green roofs can be hindered by the perceived fire risk and short experience with modern green roofs in some cou...

Performance-based structural design is still in a comparatively developmental phase for fire hazard when compared to that of, for example, earthquake excitation. Addressing a significant weakness in performance based design for fire, the present study aims to propose appropriate intensity measures (IM) for a fire hazard that has a robust correlatio...

Narrow gaps and cavities present in modern construction systems have been identified as one of the key elements that may enable fire spread after an initial fire ignition. Although there are existing models to predict the exposure of the inner linings of a cavity when exposed to a fire, these models have a significant amount of error or are limited...

Risk assessment in communities or regions typically relies on the determination of hazard scenarios and an evaluation of their impact on local systems and structures. One of the challenges of risk assessment for infrastructure operators is how to identify the most critical scenarios that are likely to represent unacceptable risks to such assets in...

Fires in open plan compartments have been the subject of much research over the past decade. This article presents results from an experimental study conducted to explore factors that influence fire dynamics in open-plan compartments with an exposed timber ceiling. A reduced scale testing methodology is proposed and supported by contrasting observe...

The term resilience is being more widely adopted in fire safety engineering, however, its comprehensive description is not clearly explained or correctly applied in practice. This study, therefore, defines the categories, dimensions, characteristics, capacities, objectives and missions possessed by resilience to provide a holistic understanding of...

Risk assessments are used to inform decision-making in hazardous systems. The process involves highly technical steps such as quantifying uncertainty and it is typically carried out by subject matter experts with a robust engineering background. The process also involves value-loaded steps such selecting the risk acceptance criteria for evaluating...

Fire safety remains a major challenge for engineered timber buildings. Their combustible nature challenges the design principles of compartmentation and structural integrity beyond burnout, which are inherent to the fire resistance framework. Therefore, self-extinction is critical for the fire-safe design of timber buildings. This paper is the firs...

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire enginee...

Recent high-rise residential building fires in Australia have instigated national debate over the adequacy of the current regulatory and enforcement framework in ensuring that an acceptable level of fire safety is achieved and maintained throughout the life of a building. While much of the current debate and reform has focussed on the role of the F...

A series of large-scale experiments has been conducted on under-ventilated mass timber room compartments. In order to characterise the influence of the fuel nature and geometry on the fire dynamics, the movable fuel load in the compartments was alternated between a kerosene pool fire and a wood crib, while the number of exposed timber surfaces was...

Fire safety engineering accreditation and licensing is a subject of much debate in many jurisdictions especially following the Grenfell Tower fire and as a result of the many issues that have been brought to light following similar cladding related fires around the world. It is argued elsewhere that the lack of a well defined accreditation and lice...

Structural fire safety requirements implicitly balance up-front investments in materials (protection or element sizing) with improved performance (loss reductions) in the unlikely event of a fire. For traditional prescriptive fire safety recommendations, the underlying target safety levels are not clear to the designer, nor is the associated balanc...

This manuscript presents tools and data that serve to enable an evaluation of the risk associated with vertical fire spread on buildings. A highly detailed context to cladding fires is described to unveil the complexity and magnitude of the problem and to identify gaps of information. An engineering framework is then developed which delivers requir...

Risk assessment in communities or regions typically relies on the determination of hazard scenarios and an evaluation of their impact on local systems and structures. One of the challenges of risk assessment for infrastructure operators is how to identify the most critical scenarios that are likely to represent unacceptable risks to such assets in...

Fire Safety Engineering is often implemented within a framework that requires a recognized and recognizable profession. This article reviews the current state of various attributes that define Fire Safety Engineering as a profession. It is argued that: 1) reliance on prescriptive solutions opens the domain to practitioners that do not possess the r...

Fires in open plan compartments have been the subject of much research over the past decade. The impact of exposed CLT on the fire dynamics in such compartments is also receiving a great deal of interest as trends in timber buildings include also open plan buildings. This article presents some initial results from an experimental study which was co...

Large accidents throughout the 20th century marked the development of safety fields in engineering, devoted to better identify hazards, understand risks and properly manage them. As these fields evolved rather quickly and moved from a compliance to a risk-based approach, a significant delay in this transition was experienced in fire safety engineer...

One of the largest unknowns in structural fire engineering design is the fire itself, particularly in large internal environments, where real fires have been observed to travel around the floor plate. Several methodologies have been proposed to characterise these fires, most of which rely on the separation of the fire exposure into two so-called fi...

This report sets a path of commitment among academia, government and industry to deliver a sustainable provision of professionals. Without a sustainable provision of professionals, it will not be possible to professionalise Fire Safety Engineering. Taking into account the needs, constraints and limitations of all stakeholders, the report emphasises...

Probabilistic analysis is receiving increased attention from fire engineers, assessment bodies and researchers. It is however often unclear which probabilistic models are appropriate for the analysis. For example, in probabilistic structural fire engineering, the models used to describe the permanent and live loads differ widely between studies. Th...

https://ascelibrary.org/doi/full/10.1061/%28ASCE%29ME.1943-5479.0000795 This article discusses critical infrastructure resilience in terms of how it could be incorporated into the existing safety and security practices, namely the ISO 31000 risk management standard. The article starts by outlining the resilience discourse, focusing on the organiz...

Glass structures have been increasingly utilised in modern construction for decades with load-bearing walls or facades as the most common elements. However, the use of glass beams has recently been given more attention but its application as load-bearing elements has been limited by the low tensile resistance, its brittle behaviour during failure a...

While maintaining a minimum level of service and rapidly restoring services to normal are key components of critical infrastructure (CI) resilience, who should and how to define these parameters remains under debate. Rarely solicited in the debate, yet integral actors in CI resilience, is the general public. In response to this, this paper presents...

Read for free until May 2, 2020:https://authors.elsevier.com/a/1ajfw3OQ%7EfLcPG Resilience: a highly debated term, with what seems to be an endless amount of slightly varied definitions depending on the sector, domain, or researcher who is addressing the topic, mainly boils down to rebounding after a crisis. For critical infrastructure (CI), the...

This paper reports on two experiments conducted in a fire resistance furnace to study the differences in the boundary conditions, the fire dynamics and the fuel required to run the furnace when a combustible timber specimen as opposed to a non-combustible concrete specimen is tested. In both experiments measurements were taken in the furnace to eva...

Decision-making under risk has been a key issue in systems with a potential for major losses such as chemical process industries (Bhopal-1984, Toulouse-2001) or high occupancy buildings (World Trade Center-2001, Grenfell Tower-2017). For the past decades, engineering disciplines have supported risk management decision-making through the implementat...

Probabilistic analysis is receiving increased attention from fire engineers, assessment bodies and researchers. It is however often unclear which probabilistic models are appropriate for the analysis. For example, in probabilistic structural fire engineering, the models used to describe the permanent and live load differ widely between studies. Thr...

This paper summarises the outcomes of an exploratory experimental study on the response of heat-induced concrete spalling during fire. The occurrence of spalling was studied against the following parameters: moisture content of concrete, amount of micro polypropylene fibres incorporated into concrete, and heating conditions. Repeated tests are unde...

The use of glass as a structural material has increased in the built environment over the last decades. Despite the large number of research projects and studies, it still poses difficulties in structural design. This particularly applies to the behaviour of glass in fire and under elevated temperatures since the available data on temperature depen...

Fire resistance is an important characteristic for all building structures regardless the building materials used. Methods for fire resistance testing were developed already before 1900 to measure the response of the structure in fire and compare different products. In the last decade, the increased popularity of timber buildings has led to a renew...

A probabilistic risk assessment (PRA) is commonly accepted as a tool for performance based design in fire safety engineering, but the position of PRA in the design process, the relationship between different acceptance concepts (absolute, comparative, ALARP), and the responsibilities of the designer remain unclear. Aiming to clarify these aspects,...

Resilience of Critical Infrastructure (CI) has been a research focus for several years now, with efforts being made to develop methods for the analysis and assessment of CI resilience. However, these efforts are often carried out without consideration of enriching societal risk or resilience assessments with knowledge of the resilience of CI. Beari...

No consensus currently exists on how to measure and evaluate Critical Infrastructure (CI) resilience. Attempting to use the public’s declared coping capacity as a target for CI resilience, this paper explores how to develop relevant resilience performance measurements that enable comparison to the tolerance levels of the general public. To do so, o...

We present the application of a simple probabilistic methodology to determine the reliability of a structural element exposed to fire when designed following Eurocode 1-1-2 (EC1). Eurocodes are being used extensively within the European Union in the design of many buildings and structures. Here, the methodology is applied to a simply-supported, rei...

Experience shows that the assessment of fire resistance of steel elements based on European standards is conservative, while advanced methods are complex and time consuming. The analysis of existing methods for the tested steel beam exposed to bending and standard ISO fire was conducted in the scope of the international Round Robin study. The compa...

Procjena metoda proračuna čeličnog nosača izloženog požaru Prema iskustvu, procjena požarne otpornosti čeličnih elemenata prema europskim normama je konzervativna, a napredne metode proračuna su složene i dugotrajne. U sklopu međunarodne Round Robin studije, procjena postojećih metoda analizirana je za ispitani čelični nosač izložen savijanju i sta...

Procjena metoda proračuna čeličnog nosača izloženog požaru Prema iskustvu, procjena požarne otpornosti čeličnih elemenata prema europskim normama je konzervativna, a napredne metode proračuna su složene i dugotrajne. U sklopu međunarodne Round Robin studije, procjena postojećih metoda analizirana je za ispitani čelični nosač izložen savijanju i sta...

Glass has been overwhelmingly used for windows and facades in modern constructions, for many practical reasons, including thermal, energy, light and aesthetics. Nevertheless, due to the relatively low tensile strength and mostly brittle behaviour of glass, compared to other traditional materials, as well as to a multitude of interacting structural...

The poster explains the IMPROVER project. The project: IMPROVER aims to improve European critical infrastructure resilience to crises and disasters through the implementation of combinations of societal, organisational and technological resilience. The aim: More efficient uptake of risk assessments through Member States and Associated Countries a...

This report is a summary of the Tisova fire test, conducted in the Czech Republicin January 2015. It is the first of two reports into these test, and describes thebuilding, the experimental setup and discusses the results obtained on the day ofthe test. The results are discussed with a specific focus on the travelling nature ofthe fire in the build...

As a natural material, the response of timber structures under normal conditions and to fire is subject to wide variability. Deterministic models therefore struggle to reflect the reality of the response of timber since small variations in input influence the output significantly. However it is relatively straightforward to quantify uncertainties i...

Fires can cause substantial damage to structures, both non-structural and structural, with economic losses of almost 1% GDP in developed countries. Whilst design codes allow engineers to design for the primary design driver, property protection is rarely, if ever, designed for. Quantification and design around property protection has been used for...

This paper details a round robin study of the calculated response of structures in fire. In this instance, the study is based on one of two fire tests which were conducted on steel beams in a horizontal fire resistance furnace. The two specimens in the tests were identical having come from the same cast flow. The tests were conducted according to E...

In this paper, fractional factorial design (FFD) and deterministic sampling (DS) are applied to a finite element (FE) model of a fire resistance test of a loaded steel beam, to investigate how uncertainties are propagated through the FE model. The sought quantity was the time when the deflection of the beam exceeded 225 mm. The FFD method was used...

To deal with increasing interdependency among critical infrastructures and new types of hazards emerging, the H2020-funded project IMPROVER has developed a harmonized approach for resilience management has been developed. This resilience management framework will give operators an understanding of, and capability to improve, their own resilience, a...

Two furnace tests, using two different fire exposures, on unbonded post-tensioned concrete slabs (1700 × 1200 mm) are reported. Local curvature is measured along two lines approximately in the middle of the slabs both parallel (longitudinal) and orthogonal (transverse) to the prestressing direction. More pronounced curvature in the transverse direc...

Glass is seeing a growing interest as a structural material as a result of its relatively good strength to weight ratio and the obvious aesthetic benefits of its use in buildings. However due to the sensitivity of glass to thermal shock and the considerably temperature-dependent behaviour of interlayer materials as a result of their visco-elastic n...

This report outlines the fundamentals of hazard mapping, beginning with the 4 steps needed for hazard mapping: 1) the identification of the hazard in question and the region; 2) the specification and temporal description of the hazard; 3) the definition of the probability of occurrence of the hazard; and finally 4) the definition of the hazards’ in...

Topic and purpose Clear definitions of key terms are essential in order to avoid misunderstandings and to help deliver informed decision-making during cascading disasters. This is particularly important within the overlapping fields of emergency management, risk management and disaster management, where certain terms may be understood differently b...

Modelling of structures exposed to fires is prone to be heavily influenced by uncertainties in geometrical parameters, thermal material data as well as uncertainties in the boundary conditions. Assessing the effects and influences in variations of all the uncertain parameters is often cumbersome and traditional methods are impractical thus modellin...

In recent years, the concept of resilience started to dominate strategic, operational as well as political domains of modern societies. Living in highly interconnected environment, where layers of infrastructures, people and economic interests interact creating both opportunities and vulnerabilities, different countries around the world turned towa...

Scenarios are frequently used as an instrument in research projects. The scope, the type of story- or timelines, the level of detail and other characteristics are determined by the overall objective of the project, the stage of development they are used in and the specific purpose for their elaboration. This report clarifies the underlying methodol...

The ultimate goal of the CascEff project is the development of the CascEff Incident Evolution Tool (IET). To prove the functionality and usability of the IET it needs to be tested and validated in some way. However, it is not obvious against what such a tool should be validated. For this purpose a number of scenarios were selected in the project. T...

The Tisova Fire Test was a large fire test conducted in the Czech Republic in January 2015 inside of a 4-storey concrete frame building, with concrete and composite deck floors. The test compartment was on the ground floor and the fire compartment had a total area of ca. 230m2 with a height of 4.4m. The fire compartment included four columns from t...

p>The current paper reports about the progress in the ongoing European project IMPROVER (Improved risk evaluation and implementation of resilience concepts to critical infrastructure), in which a fundamental part is devoted to technological resilience concepts. Within the project a general methodology for resilience evaluation is developed, in whic...

The Tisova Fire test was a large fire test conducted inside of a 4-storey building in the Czech Republic in January 2015. This paper presents initial FDS modelling which was intended to help during the planning of the test. The approach taken was to conduct FDS modelling of discrete individual wood cribs of various sizes and configurations. The ove...

Timber is an desired material for structural applications due to its green credentials and attractive external appearance. Fire safety design of timber structures is largely limited to considering the exposure of elements to the standard fire, to which timber demonstrates exceptional resilience. This paper reports on a series of tests which were ca...

Recent trends in structural fire engineering research have focussed on the response of buildings with large open plan spaces to so-called travelling fires. These fires travel horizontally across the floor plate of a building and result in time and spatially varying thermal exposure and response of the structure to the fire. What has received little...

A local fire flame around a steel column. Plate thermometer data successfully used to predict steel temperature.

A localized fire is a fire which in a compartment is unlikely to reach flash-over and uniform temperature distribution. Designing for localized fires is generally more difficult than for flash-over compartment fires because of the complexity of the problem. There is also a lack of experimental data. We report here on a full scale test series on a s...

The Pacific Earthquake Engineering Research (PEER) Center’s Performance Based Earthquake Engineering (PBEE) framework is well documented. The framework is a linear methodology which is based upon obtaining in turn output from each of the following analyses: hazard analysis; structural analysis; loss analysis, and finally decision making based on va...

This paper reviews the phenomena of concrete behavior which is captured in the material data of the Eurocode and reviews additional phenomena which may be included to improve results in certain cases. As a case study, a series of tests which were conducted by Anderberg and Thelandersson in the 1970's in Sweden on concrete samples are studied using...

This study investigates the thermal exposure to a full scale steel column exposed to localized fires. The steel column is a six meters long cylinder with a diameter of 200 mm. The fires are heptane and diesel fires from cylindrical pans of diameter 1.1 m and one diesel fire using a pan of 1.9 m in diameter. The main result is the experimental data...

Two furnace tests, using two different fire curves, on unbonded post-tensioned concrete slabs are reported. As a signature of the curvature, the relative deflections on the cold surfaces are measured in directions both parallel (longitudinal) and orthogonal (transverse) to the prestressing tendons. The curvature is more pronounced in the transverse...

A methodology for assessing the vulnerability of tall buildings to fire on multiple floors is presented. It is based upon numerical modelling of real and imagined tall building structures. Key results from the modelling work are also presented here to introduce and illustrate two potential failure mechanisms for tall buildings in multiple floor fir...

The practice of structural fire safety engineering is gradually moving towards more frequent use of calculation and computation to enable more realistic estimates of the fire resistance of structures. These approaches are in general ad-hoc and do not account for the many inherent uncertainties in either the demand or the capacity. This paper will u...

Fire investigation has generally focused on the identification of the cause and origin of a fire. Thus methodologies developed for this purpose are mainly based on the dynamics of fire growth and the investigation of its effect on the different objects within the structure affected by the fire. It is unusual to come across a fire investigation emph...

For the development of performance based design on a proper scientific basis the use of the concept of risk is inevitable. However, the application of this concept to actual structural design is not simple because of the large ranges of probability and consequences of events which exist. This is compounded by a plethora of different actions that ca...

Developments in design methodologies and practices for structures in fire has for the last decade focussed on the horizontal stability of structures in fire. In this field there have been a number of developments of significance including the acceptance of membrane action as a viable load carrying mechanism under the large vertical displacements of...

For the development of performance based design on a proper scientific basis the use of the concepts of risk and reliability is inevitable. The application of the concept of performance based design is not simple because of the large ranges of probability and consequences of events which exist. While this concept poses major challenges, it also off...

Structural fire engineering has been benefiting for some time from a growing understanding of the fundamental mechanics that govern the behaviour of structures under thermal effects. As the field of fire engineering moves from a prescriptive to a performance based approach, this understanding is being used with growing confidence by engineers to de...