Passive Fire Protection Research Articles

Mechanical and Fire Performance of Innovative Hollow Glue-Laminated Timber Beams.

Fire safety greatly contributes to feeling safe, and it is a key parameter for the selection of building materials. The combustibility of timber is one of the main reasons to have the strict restriction on timber for use as a building material, especially for multistory buildings. Therefore, the main prerequisite for the use of timber in buildings is to ensure adequate fire resistance, using passive and active fire protection measures. This article contains the results of mechanical and fire experimental tests of both normal and innovative hollow glued laminated timber beams. A total of 10 timber beams were tested at ambient temperature, and 3 timber beams in fire conditions, which differed in cross-section type but also in the applied fire protection. The first beam was a normal GL beam without fire protection, the second a hollow beam covered by intumescent paint, while the third was also hollow, additionally protected by mineral wool infill inside the holes. The load-carrying capacity of the hollow beam in ambient conditions was estimated at 65% of the load-carrying capacity of a normal GL beam. Fire tests indicated that hollow timber beams with both intumescent paint and mineral wool infill failed at a similar time as a normal GL beam without fire protection. One-dimensional β0 and notional charring rates βn were obtained. Time to the protective material failure was 17 min. The main cause of failure of hollow beams was the appearance of delamination due to the reduction of the lamella bonding surface.

Numerical analysis and structural fire design of protected SHS steel columns with thermally enhanced gypsum-based mortars

Fire protection materials should restrict the temperature increase in steel members to prevent premature steel damage and structural failure in case of fire. The design of fire protection materials must be then precise, efficient, and optimized to make steel structures more competitive in the construction sector, thus reducing the impact of one of the worst disadvantages of steel structures. Therefore, this paper presents a numerical investigation into the performance of gypsum-based mortars enhanced with silica micro and nanoparticles as passive fire protection materials to protect the steel columns against fire. Square hollow section (SHS) steel columns were considered for this investigation. Firstly, finite element models were developed and confronted with observations from experimental tests previously carried out by the authors. Secondly, a parametric study was undertaken to study the role of several parameters on the structural fire performance of such columns when exposed to the ISO 834 standard fire curve, including the fire protection thickness and type (composition), column slenderness and load level. Then numerical and analytical results from current design rules in Eurocodes were compared. And finally, changes to the steel temperature prediction method in current design standards were proposed based on the findings of this study. It was observed that the design predictions excessively underestimated the actual fire resistance of the protected SHS steel tubular columns, especially when fire protection mortars with silica micro and nanoparticles were used. The thermal properties of fire protection mortars as a function of temperature must be considered in the structural steel temperature prediction when subjected to fire conditions. It is then strongly recommended that a new revision should be done in the next generation of Eurocodes on this topic based on the proposed modifications or the presented findings.

A building information modeling‐fire dynamics simulation integrated framework for the simulation of passive fire protection in a mid‐scale cross‐laminated timber compartment: Numerical implementation and benchmarking

AbstractConstruction fires are a big threat to worker safety and property safety. Mass timber buildings under construction are largely unprotected as they are not yet equipped with active fire protection systems. With the addition of Types IVA, B, and C, the 2021 International Building Code adopted stricter requirements for mass timber buildings that are under construction. Cross‐laminated timber (CLT) is used as the primary structural element for high‐rise mass timber buildings. However, to date, limited number of research studies investigated the impact of passive fire protection for CLT buildings that are under construction. To facilitate a better understanding of construction fires and their consequences, it is necessary to develop a numerical modeling solution for the early phases of a CLT construction project, which can be achieved by using building information models together with fire dynamics simulation (FDS). However, the numerical modeling technique must be benchmarked against experimental data first to then extrapolate the modeling technique to explore other parameters and conduct FDS analysis. Therefore, this paper develops and benchmarks a numerical modeling solution against a mid‐scale CLT compartment fire test by applying the FDS tool to simulate the fire behavior within the CLT compartment. The FDS analysis results are expected to validate the practicality of simulating the fire behavior in CLT structures using the numerical model proposed in this study. The overarching goal of this study is therefore to develop a comprehensive numerical modeling solution to simulate and assess passive fire protection sequencing in CLT buildings that are under construction.

Circular economy implementation in the development of fire-retardant materials used in construction, industry, and general-purpose products

During a fire, passive fire protection systems are designed to prevent the spread of flames, smoke, and toxic gases. The new fire-retardant (FR) material, used for passive fire protection, is created by combining copolymers (VC–co–VAc) (Slovinyl KV 173) and PVC K70 with expanded graphite and plasticizers/modifiers such as diisononyl phthalate - DINP, diisononyl terephthalate - DINTP, dioctyl adipate - DOA, as well as plasticizers that are synthesized based on tertiary recycling of waste poly(ethylene terephthalate) (PET), 1-hexadecene, azodicarbonamide (ADC), tri(p-cresyl phosphate), epoxidized soybean oil (ESO) and acrylate emulsion (DH50, Ecrylic, or Flexryl, etc.). The obtained material's morphology was examined using an emission scanning electron microscope (FESEM) field. Tensile testing was used to determine the mechanical properties of the obtained samples, as well as Shore A hardness and toughness using the Charpy impact test. All samples obtained were tested according to non-flammability standards. To conform to the new trend of "green economy," the development of novel eco-friendly FRs with improved thermal and mechanical properties will include careful consideration of environmental protection and sustainable development.

Fire resistance evaluation of gypsum plasterboard walls using machine learning method

Gypsum plasterboard walls are commonly used in constructions and they provide the passive fire protection as separating elements. The fire resistance of the wall is largely dependent on the thermo-mechanical properties of the gypsum plasterboard. Numerical modelling of the fire behaviour of gypsum plasterboard cracking, fall-off and gypsum induced water transport is a great challenge. The fire resistance of the wall is assessed by performing expensive fire tests or conservative empirical calculations. This paper presents the evaluation of fire resistance of steel stud gypsum plasterboard lined walls by means of machine learning. A series of large, medium and small scale fire tests are performed or gathered on the gypsum plasterboard walls in order to create a data base. Various tracks are considered when using machine learning in order to predict the failure times and the temperature evolution on the unexposed side of these walls. The machine learning results are compared with test results, with the separating function method and finite element method results.

Some recent developments and testing strategies relating to the passive fire protection of concrete using intumescent coatings: a review

PurposeIn the present article, the authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. Here, the main thrust is placed on the spalling phenomenon of concrete elements when exposed to elevated temperatures and fires.Design/methodology/approachIn this context, it has been long established that prolonged thermal insult on concrete members will lead to egress of water, both physically bound as well as those present as water of hydration within the concrete matrix, in the form of steam through microchannels and associated pathways of least resistance, often resulting in the flaking of the surface of the structure. The latter process can ultimately lead to the exposure of the ferrous-based reenforcement elements, for instance, to higher temperatures, thus inducing melting. This, in turn, can result in substantial loss of strength and load-bearing capacity of the structural element that is already undergoing disintegration of its base matrix owing to heat/fire. Even though spalling of concrete structures has long been recognized as a serious problem that can often lead to catastrophic failure of infrastructures, such as buildings, bridges and tunnels, the utility of intumescent coating as a mitigation strategy is relatively new and has not been explored to its fullest possible extent. Therefore, in the latter parts of the review, the authors have endeavored to discuss the different types of intumescent coatings, their modes of actions and, in particular, their wider applicability in terms of protecting concrete elements from detrimental effects of severe or explosive spalling.FindingsGiven that spalling of concrete components is still a very serious issue that can result in loss of lives and destruction of critical infrastructures, there is an urgent need to formulate better mitigating strategies, through novel means and methods. The use of the intumescent coating in this context appears to be a promising way forward but is one that seems to be little explored so far. Therefore, a more systematic investigation is highly warranted in this area, especially, as the authors envisage a greater activity in the building and commissioning of more infrastructures worldwide incommensurate with augmented economic activities during the post-COVID recovery period.Originality/valueThe authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. The authors have also included the results from some recent tests carried out at the facilities using a newly commissioned state-of-the-art furnace.

Investigation of Thermal behaviour of Swelling Anti-Fire Composite Materials Identified with RFID Technology

Passive fire protections are one of the safety systems which are installed commonly in buildings. As every kind of such systems these protections have to controlled according to legal regulations. To facilitate periodic checks RFID technology can be successfully used. In this paper, thermal behaviour of produced swelling materials suitable for passive fire protection was examined and thermal endurance of RFID tags used to identify these protections was analysed as well. The results achieved in this study showed expected thermal behaviour of the swelling materials which fulfilled the whole space of the protections blocking spreading fire and smoke. Further, it was noticed that a gasket sealant and a high-temperature silicone allowed to decrease temperature affecting RFID tags. Paper-face and hard RFID tags withstood the applied thermal exposure and their readability was restored after cooling down the tags to about 120°C. This means that it is likely that these tags can resist small fire incidents on condition that temperature affecting the tags does not exceed a decomposition temperature of materials used for their production.

Structural Fire Performance of Concrete-Filled Built-Up Cold-Formed Steel Columns.

Concrete-filled composite columns are widely used in the construction industry, exploiting the benefits of combining steel and concrete, providing, for instance, high load-bearing capacities and enhanced fire resistance. These solutions are extensively used in high-rise buildings and/or when high fire resistance performance requirements are imposed. In this exploratory research, a new type of concrete-filled composite column is investigated using fire resistance tests. Promoting the use of cold-formed steel products and developing innovative solutions for low-rise buildings with lower passive fire protection requirements led to the solutions presented in this research. Hence, a set of fire-resistance tests were undertaken on concrete-filled closed built-up cold-formed steel columns, where single cold-formed steel shapes are combined and fastened to create a box-shaped cross-section. The experimental results were then compared with the corresponding bare steel solutions to assess, in detail, the observed enhancements. Additionally, the effect of restraint on thermal elongation was assessed.

수동화재보호 재료가 적용된 구조부재의 화재하중에 대한 강도 특성

In offshore installations, fires cause the structure to lose its rigidity and it leads to structural integrity and stability problems. The Passive Fire Protection (PFP) system slows the transfer rate of fire heat and helps prevent the collapse of structures and fatality. Especially, intumescent epoxy coating is widely used in the offshore industry, and not only is the material cost expensive, but it also takes a lot of time and cost for construction. Several studies have been conducted on the efficient application and optimal design of the PFP system. However, the mechanical properties and the strength of the PFP material have not been considered. In addition, researches on the correlation between the thickness of PFP and the structural behavior were insufficient. Therefore, this study aims to analyze the thermal and mechanical effects of the PFP on the structure when it is applied to the structural member. In particular, it is intended to resolve the change in strength characteristics of the structural members as the thickness of the PFP increases.

Development of Passive Fire Protection Mortars

During a fire event, the stability of steel structures may be compromised, and structural collapse may occur due to the loss of their mechanical resistance as the temperature increases. One of the solutions to reduce this problem is the protection with a coating using enhanced fire-resistant mortars. This paper reports a detailed experimental work aiming to develop gypsum and cement-based mortars for passive fire protection and evaluate their composition’s effect in the final thermal performance. Two types of specimens were tested: (i) small specimens composed of a mortar coating (10 mm thick) and one steel plate and (ii) square section short tubular steel columns with 20 mm of coating. The evaluation of the thermal protection was carried out by (a) measuring the thermal gradient between the exposed surface of the protected steel plate under high temperatures and the mortar-steel interface and (b) assessing the fire resistance of the short steel columns. It was concluded that the compositions with gypsum binder present better thermal insulation than the cementitious compositions. Additionally, the introduction of nano- and microparticles of silica still slightly improved the thermal insulation of the tested compositions.

Analysis of fire-induced progressive collapse for topside structures of a VLCC-class ship-shaped offshore installation

ABSTRACT This study extends the authors’ previous numerical and experimental studies simulating the progressive collapse of steel stiffened-plate structures in fire events (Paik JK, Ryu MG, He KH, Lee DH, Lee SY, Park DK, Thomas G. 2021a. Full-scale fire testing to collapse of steel stiffened plate structures under lateral patch loading (part 1) – without passive fire protection. Ships Offsh Struct. 16(3):227–242; Paik JK, Ryu MG, He KH, Lee DH, Lee SY, Park DK, Thomas G. 2021b. Full-scale fire testing to collapse of steel stiffened plate structures under lateral patch loading (part 2) – with passive fire protection. Ships Offsh Struct. 16(3):243–254; Ryu MG, He KH, Lee DH, Park SI, Thomas G, Paik JK. 2021. Finite element modeling for the progressive collapse analysis of steel stiffened-plate structures in fires. Thin-Walled Struct. 159:107262). Specifically, this study demonstrates that the computational models developed in the earlier studies can be applied to the analysis of the heat transfer and fire-induced progressive collapse behaviour of the topside structures of a ship-shaped offshore installation. To this end, a hypothetical VLCC-class floating, production, storage and offloading (FPSO) unit hull structure is considered, and transient thermal elastic-plastic large-deformation finite element models are used. The novelty of this study and its contribution to industry are the development of a practical procedure to ensure the fire safety of large-scale steel-plated structures with complex geometries.

Оценка эффективности способов обеспечения пожаровзрывобезопасности транспорта на водородном топливе

PURPOSE. The paper examines the issue of switching to hydrogen as motor fuel in terms of fire and explosion safety. Taking into account the peculiarities of various hydrogen storage methods, the specifics of emergency situations development and insufficiency of the existing methods of passive and active fire and explosion protection for vehicles running on the given gas are discussed. METHODS. Analysis of available scientific data on hydrogen as motor fuel storage methods used in transport has been carried out. An assessment of the possibility to use a nitrogen fire engine for the described options for ensuring explosion safety has been made. FINDINGS. The insufficiency of existing methods for passive and active fire and explosion protection of vehicles running on hydrogen has been shown. To solve the identified issues, it is proposed to use a nitrogen fire engine to create local gaseous extinguishing environment around a hydrogen-powered damaged vehicle, as well as portable toximeters to control atmosphere explosion risk. RESEARCH APPLICATION FIELD. The results are applicable to ensure fire and explosion safety of vehicles and transport infrastructure. CONCLUSIONS. It is shown that the existing methods of passive and active fire and explosion protection for hydrogen-powered vehicles do not fully ensure their fire and explosion safety. In fire departments tactics in relation to such objects, actions under the threat of explosive hydrogen-air environment have not been worked out, there are no methods of mobile assessment for hydrogen level in the atmosphere. One of the options for ensuring explosion safety of hydrogen-air environment can be using a nitrogen fire engine to create local gaseous extinguishing environment around a hydrogen-powered damaged vehicle. Portable toximeters can be used to quickly determine hydrogen level in the atmosphere, which allow getting quick results and controlling potential environment hazard by combustible substance concentration.

Thermal and Structural Behaviour of Offshore Structures with Passive Fire Protection

In offshore structures, hydrocarbon fires cause the structure to loose its rigidity rapidly and this leads to structural integrity and stability problems. The Passive Fire Protection (PFP) system slows the transfer rate of fire heat and helps to prevent the collapse of structures and human losses. The vital design factors are decided in the detailed design stage. The determined design thickness must be accurately applied in the fabrication yard. However, there are many cases that the PFP is overused because of various reasons. This excessive application of the PFP is an unavoidable problem. Several studies have been conducted on the efficient application and optimal design of the PFP. However, the strength of the PFP has not been considered. In addition, research studies on the correlation between the thickness of the PFP and the structural behaviour are not widely available. Therefore, this study attempts to analyse the thermal and mechanical effects of the PFP on the structure when it is applied to the structural member. In particular, it is intended to determine the change in the behaviour of the structural member as the thickness of the PFP increases.

Development of fire retarding composite board for fire compartmentation application using waste denim: A review

This paper represents a comprehensive review work to understand the utter need to recycle denim waste and its use as a structural member with good mechanical and fire retardant properties for compartmentation under Passive Fire Protection systems. At present the amount of denim waste recycled is very small as compared to what is landfilled and studying the rate of denim waste generation and its associated problems there is certainly a scope for new effective denim waste recycling methods. This paper includes an intensive review on the best present fire retardant and mechanical properties improving methodologies for denim fabrics. Despite the fact that denim fabric is virtually entirely made of cotton (99%), the spinning process increases the LOI value from 18.5 percent (cotton) to 20.1 percent (denim). Various compositions, formulations, and application tactics of various fire retardants, such as boron-based, phosphorus-based fire retardants, and so on, were investigated to improve the composite's fire retardancy upto 89 percent. To considerably improve the physical and mechanical characteristics of the composite, different composite manufacturing processes such as film stacking, compression molding, resin transfer molding, vacuum infusion, hand lay-up, and hot pressing method were investigated. According to the findings, denim based composite boards have huge potential for fire compartmentation application. This paper provides the direction towards development of such boards which will not just help in denim waste management but also provide important component of passive fire protection for much needed building fire safety.

Fire Safety of Tall Buildings: Approach in Design and Prevention

Design of tall buildings is a multidisciplinary process and requires a wide range of measures to take to withstand in various emergencies. Fire is one of them and can cause of chaotic situations considering hundreds of users in multistorey. The measures are divided into two categories, active and passive fire protection. Architectural design and details are part of the passive systems. Along with the fundamental solutions in fire protection, tall buildings require more specific and often design-specific solutions. Detection and extinguishing systems are part of the active fire protection systems. The failure of the World Trade Centre pointed the vulnerability of steel structures; the fire at the Grenfell Tower pointed the significance of the enveloping materials for facades, and the fire at the One Meridian Tower pointed the significance of the active systems for every floor. The paper focuses on the fire case studies of tall buildings and follows with an assessment of the approaches in architectural design and detailing applicable from the structural design to the finishing interior detailing.

Passive Fire Protection of Taeda pine Wood by Using Starch-Based Surface Coatings.

The present paper reports the preliminary results relating to the development, subsequent application, and testing of environmentally benign starch-based formulations for passive fire protection of wood substrates. This study evaluated the effectiveness of starch colloid coatings applied onto the wood surface with a view to improving its performance when exposed to the external heat flux (35 kW/m2) during cone calorimetric tests. The formulations were prepared from aqueous colloid solutions of either starch alone, or in combination with inorganic salts, such as: sodium carbonate, Na2CO3, potassium carbonate, K2CO3, and diammonium hydrogen phosphate, (NH4)2HPO4. The fire performance of Taeda pine wood samples, where their top surfaces were treated with these formulations, was compared with the control sample. The thermal and combustion characteristics of the tested samples were determined with the aid of thermo-gravimetric analysis (TGA), bomb and cone calorimetric techniques, and a steady state tube furnace coupled to an FT-IR spectrometer. A significant boost of fire protection was observed when starch formulations with added inorganic salts were applied onto the wood surfaces, compared with the control sample. For example, the presence of K2CO3 in starch colloid solutions resulted in a notable delay of the ignition and exhibited a reduction in the heat release parameters in comparison with the untreated wood substrate.

Challenges in the adoption of mobile information communication technology (M-ICT) in the construction phase of infrastructure projects in the UK

PurposeThe purpose of this paper is to investigate the challenges faced with mobile information communication technology (M-ICT), more specifically tablet software, in the construction phase of UK infrastructure projects. Quality assurance in the context of passive fire protection is scrutinised, where M-ICT use is prevalent, to provide an industry perspective.Design/methodology/approachThe research design is founded on exploratory multiple case study approach. Specific themes are developed, based on a critical review of previous ICT studies. The themes identified are used to inform a qualitative interview protocol for investigating three large UK infrastructure projects. Each project is at different stages in the construction phase, with varying examples of M-ICT implementation in use. Participants are interviewed regarding their experiences of the implementation of M-ICT on each project.FindingsFindings identify diverse experiences across each project. Single and multiple M-ICT platforms are currently being used, with individual stakeholders using ICT in isolation, and in some instances, multiple project stakeholders are using it together. Complete replacement of paper-based processes is evident in one case study, but more commonly, digital technology is being used in parallel to traditional paper-based processes. The challenges, although varied across each case study, can be categorised under the themes of Technology (IT support, ICT infrastructure, IT security, contractual, software), People (social aspects, user competency, safety), Technical Compliance (technical compliance evidence) and Process (conventional processes).Originality/valueIt is recommended that each theme be reviewed at project commencement, with all key stakeholders, to ensure key aspects are considered prior to M-ICT deployment. This will ensure avoidance of challenges reported and maximise the opportunities that are available through M-ICT in a multi-stakeholder infrastructure project.

Jetfire lab: Jetfire at reduced scale

This article addresses the development of a bench-scale test (jetfire lab) mimicking the fire exposure of the large-scale jetfire facility. An experimental approach was addressed to develop direct correlation and to validate the similitude between bench-scale test and large-scale jetfire. Comparisons were made by testing Zaltex passive fire protection material in the form of panels. Novel setups were designed to make the jetfire lab able to measure time/temperature curves similar to those obtained at a large scale. The assembly of the tested samples was also investigated. An experimental protocol was elaborated to consider the junction between parts of the sample at the reduced scale. Direct correlation was found between the large and the bench scale and it was evidenced that jetfire lab can be used for preliminary study and development of new thermal barriers for fire protection.

Reliable assumptions for structural fire design of steel car parks

PurposeThis study aims to analyze and discuss the key design assumptions needed for design of car parks in steel, to highlight the impact that the increased fire loads introduced by modern cars and changes in the fire dynamics have on the design, such as fire spread leading to non-localized fires.Design/methodology/approachIn particular, a reliable fire load density to be used for structural design of car park structures is assessed, based on investigations of the fire loads of modern cars. Based on knowledge of fire load and fire performance of cars, the consequences on the fire safety design of steel structures are presented.FindingsDesign recommendation about fire load density and fire protection of common steel profiles are given. Finally, the proposed design is compared with a design practice that has been applied in many instances for car parks constructed with unprotected steel, and recommendations for a reliable design process are provided.Originality/valueNumerous car park buildings have recently been designed of steel structures without passive or active fire protection. The key assumptions that makes possible such design are local fire scenarios, outdated values of the car fire load and utilization of the ultimate steel strength. This paper identifies the shortcomings of such key assumptions, indicating the need for revisiting the methods and possibly even checking the analyses carried out for some already-built car parks.

Structural response of steel-concrete composite floor systems under traveling fires

An investigation was carried out to examine the structural response of two steel-concrete composite floor system under traveling fires. The thermal-mechanical analyses were performed using the finite element software ABAQUS, where the traveling fire exposures were defined using the improved Traveling Fires Methodology. Essential factors influencing the fire resistance of the composite floor systems, namely the fire rating and fire protection scheme of the passive fire protection were varied in this study. The composite floor systems were also exposed to an ASTM E119 standard fire and two natural fire exposures applied to a corner compartment. The results showed that fire insulations derived from prescriptive approaches may not provide adequate safety under traveling fires. Through a performance-based design procedure, improved performance under traveling fires was achieved through better allocation of the fire protection. Specifically, insulation from the interior floor beams were removed and applied to the girders and exterior floor beams. This fire safety solution is economical when compared to the simultaneous increase of fire protection of all floor beams and girders, typical of a prescriptive design approach.