Fire Resistance Performance Research Articles

Fire resistance of ultra-high performance fibre reinforced concrete due to heating and cooling

This study investigated the performance of ultra-high performance fibre reinforced concrete (UHPFRC) at elevated temperatures. The specimens were exposed to high temperatures, specifically 200, 400, and 600 °C, for 2 h.The fire resistance performance of the specimens was classified on the basis of their compressive strength, spalling, and weight loss; residual strength after heating was also examined. Results showed that UHPFRC processes excellent fire resistance in terms of flame spread and fire growth. While strength loss was not significant at low temperatures, the specimen subjected to high temperature spalled severly and showed deterioration because of heat.

Comparative Study of Fire Resistance Performance for Long Span Beams Constructed with High Strength Submarine Structural Steels According to Boundary Conditions

Requirements for building have been increased not only structural aspects but fire resistance. Therefore, a structural steel having higher strength has been developed and applied into building industry. Especially, a SM 520 and a SM 570 have good construction efficiencies in fabrication site and construction site, for these have a better welding performance and a higher strength than other structural steels. However, their fire resistance performance of them doesn’t clear until now. In this study, to compare the fire resistance of long span beam built with SM 520 and SM 570, a fire engineering technique was used using mechanical properties at high temperatures and analytical methods. As the structural grades are going up, the performance of fire resistance is shown to be decreased.

Thermal and pyrolysis analysis of minerals reinforced intumescent fire retardant coating

Abstract This study presents the results of intumescent fire retardant coatings (IFRCs) developed to investigate the synergistic effects of mineral fillers (clay and wollastonite) based IFRC towards heat shielding, char expansion, morphology, composition, gaseous products and residual weight. The fire test has been performed to study the heat shielding effect of IFRCs on the substrate using UL-1709 standards. The results showed the synergistic effect of clay and wollastonite using 5 wt.% enhanced the fire protection, performance with recorded substrate temperature 113 °C after 1-h fire test. Field Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscopy (HRTEM) showed the micrograph of compact char structure that increased char integrity due to the presence of inorganic fillers. X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) results showed the presence of boron phosphate, silicon phosphate oxide, aluminum borate in char that improved the thermal performance of IFRC up to 800 °C. X-Ray Photoelectron Spectroscopy (XPS) confirmed that 5 wt% (IFRC-5) of clay and wollastonite increased the carbon content up to 50.67%, lowering oxygen content to 27.73% in the char that enriched the fire resistance performance of the coating. Pyrolysis-Gas Chromatography-Mass Spectrometry (Pyrolysis GC–MS) confirmed that formulations IFRC-5 released less gaseous product concentration compared to IFRC-C and maximum reduction in gases was recorded from 3.4e +07 to 1.08e +07 . Thermogravimetric analysis (TGA) demonstrated in residual weight was increased to 46.45% for IFRC-5 which resulted in the high thermal stability of the coating.

Огнезащита стальных конструкций плитным материалом PYRO-SAFE AESTUVER T

Providing required (statutory) parameters of fire resistance of R 60-R 180 steel beam structures involved in ensuring the overall sustainability of buildings and structures is not possible without the use of structural fire protection. Widespread method of structural fire protection involves the use of plate materials. The use of this type of fire protection allows for the production of works without the use of “wet processes”, which is very important for the Far North with a short period of time of positive temperatures. Fire-retardant treatment of steel structures with plate materials may also be carried out without stopping the production process in the reconstruction of buildings and structures. One of the members of the group of fire retardant materials are slabs PYRO-SAFE AESTUVER T, whose composition as a filler includes perlite, glass fiber, and as a binder - cement. The article describes current research aimed at obtaining baseline data to determine fire retardant efficiency of slabs PYRO-SAFE AESTUVER T and features of the calculation of fire resistance of coated steel rod elements in order to ensure regulatory requirements for fire resistance. The studies of fire resistance performance of coatings for steel structures allowed us to obtain the variation of thermal conductivity and heat capacity of fire retardant material, when impacted by fire. To obtain these dependencies, fire tests of steel-lined columns were conducted on the bench equipment for fire tests of building structures on the experimental base of VNIIPO of Emercom of Russia (All-Russian Research Institute for Fire Protection of Ministry of Russian Federation for Civil Defense, Emergencies and Elimination of Consequences of Natural Disasters). Parameters of cladding, such as density, humidity, emissivity, thermal conductivity and thermal capacity under normal conditions were taken from reference literature. Then, in the presence of experimental data, thermo-physical characteristics (thermal conductivity and heat capacity) of the material at elevated temperatures were calculated with a computer program by solving the inverse heat conduction problem. The obtained parameters of the thermal characteristics for a given flame retardants, allowed to construct warm-up nomograms of unlimited steel plates, depending on the thickness of the steel and the thickness of cladding with PYRO-SAFE AESTUVER T slabs. As a result of the research, the obtained nomograms of fire resistance of steel structures with PYRO-SAFE AESTUVER T fire protection plates may be used for the design of passive fire protection systems at construction sites. In combination with the calculation method, these nomograms allow to reduce the usage of fire-retardant material in cladding thereby increasing the economic efficiency of fire protection of this type. In Federal State Budgetary Establishment VNIIPO the “Instruction on the calculation of the actual limit of fire resistance of steel structures with fire-retardant frameless facings made of PYRO-SAFE AESTUVER T slabs” was developed.

양단 고정단인 건축용 내화강재 적용 보부재의 해석적 내화성능 연구

건축용 내화강재가 적용된 양단 고정단 보부재의 고온 시 최대 내력과 처짐을 해석적으로 평가하였으며, 이 결과를 일반강재 적용 정정 보부재와의 비교평가를 통하여 안전성을 평가한 결과, 건축용 내화강재 적용 부정정 보부재의 내화성능을 일반 강재 정정 보부재로 평가되는 것은 안전측이었으며, 부재길이가 길어지면 처짐의 증대와 최대 내력의 감소가 유발되는 등 이에 대한 보완책이 요구되는 것으로 나타났다. The fire resistance of a statistically indeterminate beam made of fire resistant steel was analyzed using the mechanical and thermal databases and compared with that of an indeterminate beam constructed of ordinary structural steel to not only determine the fire resistance performance of a statistically indeterminate beam itself, but also to determine if it is stable to test the fire resistance performance with a determinate beam built with ordinary structural steel instead of an indeterminate beam made from fire resistant steels. The results showed that the fire resistance of an indeterminate beam consisting of fire resistant steels is better than that of a determinate beam made of SS 400 and if the length of the beam built with FR 490 is longer, the displacement of the beam is higher. In addition, the fire test with a determinate beam made of SS 400 is was more conservative than that of an indeterminate beam made of FR 490 in the range of the same length. Therefore, another measure should be considered if beams built with FR 490 are longer than thos of SS 400.

방화구획 내 스틸창호의 내화성능에 관한 실험적 연구

방화구획 내 스틸창호의 내화성능에 관한 실험적 연구

원전구조물용 고강도 콘크리트의 내화성능 평가

원전구조물용 고강도 콘크리트의 내화성능 평가

구획공간에서의 온도성상 예측을 위한 실험적 연구

점차 다양해지고 있는 건축물에서의 화재위험에 대처하기 위해 성능위주 화재안전 설계의 도입이 요구되고 있는 시점이며, 성능위주 화재안전 설계에서는 기존의 법 제도에서 제시하고 있는 설계 방법과 함께 대안적인 설계 방법을 고려하여 좀 더 합리적인 설계를 진행하게 된다. 대안적 설계를 위해서 가장 먼저 파악되어야 하는 것은 건축물에서의 화재특성이며, 이는 구획공간에서의 온도성상을 통해 예측 가능하다. 국내에서는 가열로를 사용한 내화성능 평가방법에서 표준온도 곡선을 적용하고 있으며, 화재초기에 필요한 온도성장 곡선은 <TEX>$t^2$</TEX> 성장 곡선에 의존하고 있는 실정이다. 본 연구에서는 공학적 온도성장 예측 곡선을 분석하고 실규모의 화재실험 데이터를 사용하여 실제 적용 가능한 온도성장 곡선을 분석해보고자 하였다. 구획공간에서의 공학적 온도성장 예측 기법인 BFD와 New 곡선과 <TEX>$2.4(L){\times}3.6(W){\times}2.4(H)m$</TEX> 크기의 구획 공간에서 <TEX>$0.46(L){\times}0.46(W){\times}0.15(H)m$</TEX>와 <TEX>$0.65(L){\times}0.65(W){\times}0.15(H)m$</TEX> 크기인 햅탄 풀버너를 사용한 연소실험은 실험데이터와 유사한 형태로 나타났으며, 온도가 감소하는 구간에서 New 곡선이 좀 더 나은 결과를 보여주고 있다. To deal with building fire risk which has been increasingly diversified, performance-based fire safety design is required more than ever and allows to perform more rational design considering alternative design approach. First strategy for developing alternative design is identify fire characteristics of the building like to prediction temperature in the compartment. Standard temperature curve is applied domestically in evaluating fire resistance performance using heating furnace and temperature growth curve required at early stage of fire depends on <TEX>$t^2$</TEX> growth curve. This study is intended to analyze engineering temperature growth prediction curve and evaluate the practicable temperature growth curve using a real-scale fire experiment data. Combustion experiment using heptane burner sized <TEX>$0.46(L){\times}0.46(W){\times}0.15(H)m$</TEX> and <TEX>$0.65(L){\times}0.65(W){\times}0.15(H)m$</TEX> in compartment <TEX>$2.4(L){\times}3.6(W){\times}2.4(H)m$</TEX>. Experiment result was showed results silmiar with BFD and New curves. Moreover, New courve indicated better result at the stage in temperature decay.

Drill and laser incising of lamina for fire-resistive glulam

Conventional glued-laminated timber (glulam) was not permitted to use to a wooden building in the fire preventive district since the amendments of the Building Standards. We already developed a one-hour fire-proof glulam made of Japanese cedar. We also succeeded to give one-hour fire performance to cross laminated timber by the same concept. The both structures are composed of three parts which are load-bearing part, fire-die-out part and surface part. The fire-die-out part is made of lamina incised by CO2 laser and impregnated the fire retardant evenly. As the handling of CO2 laser is not so easy for glulam manufacturer, we felt a growing need for drill incising technology. Therefore, we made pinholes of some diameters up to 2.5 mm to lamina of Japanese cedar, by a drill and investigated differences of hole position on two sides of the lamina. The maximum off-center for length and width directions was 1.8 and 3.3 mm, respectively. These off-centers are 2.3% and 41% of distances between neighboring hole on incising patterns. As the results of impregnating performance and fire-resistive performance of lamina incised by drill, significant differences were not recognized between drill incising and laser incising.

Preparation and performances of novel waterborne intumescent fire retardant coatings

Abstract The core–shell organic-modified montmorillonite (OMMT)/epoxy resin/styrene-acrylic emulsion was prepared using semi-continuous seeded emulsion polymerization and used as the binder of the waterborne intumescent fire retardant coating to improve the fire resistance performance and other basic performance such as water resistance performance, anti-yellowing and adhesion to substrates. Observation with transmission electron microscopy showed that core–shell emulsion had been synthesized successfully. The small angle X-ray diffraction results showed that OMMT was exfoliated and dispersed well in the emulsion within the appropriate content. Fire resistance test, thermal analysis, scanning electron microscopy (SEM), water resistance and yellowing resistance test respectively demonstrated that OMMT greatly improve fire resistance, thermal stability, water resistance and yellowing resistance performance with the addition of in the range of 1.5–2.5 wt.%. Moreover, the core–shell styrene-acrylic emulsion with 5 wt.% epoxy resin (E-44) improve the adhesion of the film to plywood (from 2 grade to 0 grade).

Experimental and numerical investigation of post-tensioned concrete flat slabs in fire

Purpose This paper aims to understand the structural fire performance of two-way post-tensioned flat slabs, particularly their deformations and load-carrying mechanisms in fire, and to explore the behaviour of post-tensioned high-strength self-compacting concrete flat slabs with unbonded tendons in fire. Design/methodology/approach Four tests of post-tensioned high-strength self-compacting concrete flat slabs were conducted under fire conditions. Numerical modelling using the commercial package ABAQUS was conducted to help interpret the test results. Findings Two of the specimens with lower moisture contents demonstrated excellent fire resistance performance, while the others with slightly higher moisture contents experienced severe concrete spalling. Originality/value The test results were discussed in respect of thermal profiles, deflections, crack patterns and concrete spalling. The performance of post-tensioned high-strength self-compacting concrete flat slabs with unbonded tendons under fire conditions was better understood.

Experimental Study of Fire Hazards of Thermal-Insulation Material in Diesel Locomotive: Aluminum-Polyurethane

This work investigated experimentally and theoretically the fire hazards of thermal-insulation materials used in diesel locomotives under different radiation heat fluxes. Based on the experimental results, the critical heat flux for ignition was determined to be 6.15 kW/m2 and 16.39 kW/m2 for pure polyurethane and aluminum-polyurethane respectively. A theoretical model was established for both to predict the fire behaviors under different circumstances. The fire behavior of the materials was evaluated based on the flashover and the total heat release rate (HRR). The fire hazards levels were classified based on different experimental results. It was found that the fire resistance performance of aluminum-polyurethane is much better than that of pure-polyurethane under various external heat fluxes. The concentration of toxic pyrolysis volatiles generated from aluminum-polyurethane materials is much higher than that of pure polyurethane materials, especially when the heat flux is below 50 kW/m2. The hazard index HI during peak width time was proposed based on the comprehensive impact of time and concentrations. The predicted HI in this model coincides with the existed N-gas and FED models which are generally used to evaluate the fire gas hazard in previous researches. The integrated model named HNF was proposed as well to estimate the fire hazards of materials by interpolation and weighted average calculation.

강섬유 콘크리트 혼입율에 따른 내부앵커형 콘크리트 충전기둥 내화성능에 관한 해석적 연구

Professor, Department of Architectural Engineering, University of Seoul, Seoul, 02504, KoreaAbstract - Concrete filled steel tube system has two major advantages. First, the confinement effect of steel tube improves the compressive strength of concrete. Second, the load capacity and deformation capacity of members are improved because concrete restrains local buckling of steel tube. It does, however, involve workability problem of using stud bolts or anchor bolts to provide composite effect for larger cross-sections. While the ribs inside the columns are desirable in terms of compressive behavior, they cause the deterioration in load capacity upon in-plane deformation resulting from thermal deformation. Since the ribs are directly connected with the concrete, the deformation of the ribs accelerates concrete cracking. Thus, it is required to improve the toughness of the concrete to resist the deformation of the ribs. Welding built-up tubular square columns can secure safety in terms of fire resistance if the problem are solved. This study focuses on mixing steel fiber in the concrete to impro ve the ductility and toughness of the columns. In order to evaluate fire resistance performance, loaded heating test was conducted wit h 8 specimens. The behavior and thermal deformation capacity of the specimens were analyzed for major variables including load ratio. The reliability of heat transfer and thermal stress analysis model was verified through the comparison of the results between the test and previous study.Keywords - Fire resistance, Composite column, Steel-fiber, Heat transfer, Thermal stressNote.-Discussion open until August 31, 2016. This manuscript for this paper was submitted for review and possible publication on June 22, 2015; revised December 22, 2015; approved on January 13, 2016.Copyright ⓒ 2016 by Korean Society of Steel Construction

Fire resistance of stainless steel beams with rectangular hollow section: Experimental investigation

To study the bearing capacity and failure mechanism of rectangular stainless steel beams in a fire, a series of tests were performed on S30408 stainless steel, including 3 material mechanical property tests at room temperature, 45 material mechanical property tests at elevated temperature and fire experiments of 6 rectangular hollow section stainless steel beams with two simply supported ends. Both steady tests and transient tests at elevated temperature were used to investigate the mechanical properties of stainless steel. The stress–strain curve, elastic modulus, yield strength and reduction factor of ultimate strength of stainless steel at elevated temperature were found, and the test results were compared with the results of the European Codes. The experiments studied the mechanism properties of a rectangular hollow section stainless steel beam in fire, and the failure phenomenon, heating curve, deformation curve and critical temperature of the test specimens were obtained. The effects of the sectional dimension and load ratio on the critical temperature and fire-resistance performance of the stainless steel beam were also studied. The test results show that the load ratio and section depth are the key factors for the critical temperature of a stainless steel beam in fire.

PREDICTION OF RESIDUAL STRENGTH OF COMPOSITE COLUMNS USING FEM ANALYSIS

Fires in buildings cause not only economic losses but also many casualties. A prolonged fire involves the possibility of the damage to structural members, which calls for the repair or reinforcement of the building. Since it is critical to decide whether structural members need reinforcement, the technique to determine the degree of the damage to structural members caused by a fire should be established. CFT columns are superior to generic steel columns in terms of fire resistance performance thanks to the thermal storage effect of the concrete inside the columns. Studies have suggested how to reinforce the concrete to further improve the structural strength and fire resistance performance of CFT columns. When CFT columns of a building are damaged by a fire, it is required to determine preciously how serious the structural deterioration of the members is. The purpose of this study is to evaluate the residual strength of CFT columns damaged by a fire by evaluating the temperature distribution inside the columns and determining the degree of deterioration in the load capacity of concrete and steel in relation to temperature distribution.

Effects of Hybrid Fibre Reinforcement on Fire Resistance Performance and Char Morphology of Intumescent Coating

Recent researches of fire retardant intumescent coatings reinforced by single Rockwool and single glass wool fibre at various weight percentages and lengths showed some improvements to the mechanical properties of the coatings and the char produced. Therefore, in this research the fibres were combined together in intumescent coating formulation at several weight percentages and fibre lengths to study their effects towards fire resistance performance and char morphology. The hybrid fibre reinforced intumescent coatings were subjected to two types of fire tests; Bunsen burner at 1000°C and the electric furnace at 800°C for 1 hour, respectively. Steel temperature of the coated samples during Bunsen burner test was recorded to determine the fire resistance performance. Thermal stability of the intumescent coatings and chars was determined by Thermogravimetric Analysis (TGA). The morphology of the coatings and char was then examined by using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDS) was conducted to obtain elemental composition of the samples. This research concluded that long-hybrid fibre at 12-mm length and 0.6% fibre-weight produced the top performing hybrid fibre intumescent formulation. The hybrid fibres form survived at elevated temperature, hence helped to provide structure and strengthen the char with the highest fire resistance was recorded at steel temperature of 197°C.

Fire propagation over combustible exterior facades exposed to intensified flame in Japan

With regard to fire safety for exterior walls of a building, fire-resistance performance is considered, according to the current Building Standard Law of Japan. And it was revealed that the fire safety is not specifically regulated from the viewpoint of reaction-to-fire performance, such as fire propagation caused by combustible materials or products installed on the exterior side of fire-resistant load-bearing walls. Actual fire incidents in the world have shown that massive facade fire could occur at the exterior side of building wall even when the wall itself is fire resistant. In previous studies of the authors, a test method of facade fire was proposed for evaluating the vertical fire propagation over an external wall within the same building [1,2]. Based on these studies, new domestic standard test method was established in Japan as JIS A 1310: 2015, Test method for fire propagation over building at the end of January 2015 [3]. But there was the argument that heat output of burner inside the combustion chamber was not sufficiently high in the previous study. In this paper, results of fire tests on combustible facades are discussed from the viewpoints of different strength of flame exposing facade. In this research, it was clearly found that JIS A 1310 with heat output of 900kW could be applicable for evaluating fire propagation behaviour over various types of combustible exterior facades. Language: en

Fire safety engineering applied to high-rise building facades

Fire safety of high-rise building facades is a complex problem, therefore the use of prescriptive fire codes could not be sufficient to ensure a proper building fire safety level. In new high rise buildings the fire safety of facades can be taken into account by means of performance based fire design that can help in the selection of the best technological solutions and material choices. This article deals with a case study done on the Piedmont Region Headquarters (TORRE REGIONE PIEMONTE) which is one of the highest office buildings in Italy. The Torre Regione Piemonte is located in Turin and has 45 storey and a total height of 183,61 m. The building is characterized by the closed enclosure called Grand Space which is continuous for almost the entire height of the building and contains volumes such as offices/meeting rooms named as Satellites. In order to fulfil Italian fire safety requirements, the Torre Regione Piemonte building has been assessed using the performance base design and fire safety engineering approach. This paper deals with the design process selection of the most representative fire scenarios focusing on the fire resistance performance requirements of structural and glazed elements of the facades. Furthermore, all the simulation, calculations and performance fire resistant requirements of the high rise building have been supported by specific laboratory tests and experimental results, that are reported and discussed within paper. © Owned by the authors, published by EDP Sciences, 2016 Language: en

Structure, Mechanism, and Application of Vacuum Insulation Panels in Chinese Buildings

Thermal insulation is one of the most used approaches to reduce energy consumption in buildings. Vacuum insulation panels (VIPs) are new thermal insulation materials that have been used in the domestic and overseas market in the last 20 years. Due to the vacuum thermal insulation technology of these new materials, their thermal conductivity can be as low as 0.004 W/(m·K) at the center of panels. In addition, VIPs that are composites with inorganic core and an envelope out of commonly three metallized PET layers and a PE sealing layer can provide B class fire resistance (their core materials are not flammable and are classified as A1). Compared with other conventional thermal insulation materials, the thermal insulation and fire resistance performances form the foundation of VIP’s applications in the construction industry. The structure and thermal insulation mechanism of VIP and their application potential and problems in Chinese buildings are described in detail.

혼화재 종류에 따른 고강도 콘크리트의 내화성능 평가

본 연구에서는 동일 설계기준 강도를 목표로 혼화재의 종류 및 치환율을 달리하여 콘크리트 배합설계를 실시하였으며, 이에 따른 혼화재의 종류가 고강도 콘크리트의 내화성능에 미치는 영향을 검토하고자 ASTM E119의 표준가열온도 곡선에 따른 내화시험을 실시하였다. 그 결과, 고로슬래그를 치환하는 경우 폭렬량이 현저히 저감되는 것으로 나타났으며, 실리카흄을 추가하여 치환하는 경우 폭렬량이 가장 많은 것으로 나타났다. 특히 실리카흄을 단독으로 치환하는 경우 비교적 양호한 폭렬량을 나타냈으나, 고로슬래그와 함께 치환한 시험체의 경우 분말도가 높은 실리카흄이 공극을 밀실하게 함으로써 수증기압의 증가로 인해 폭렬량이 증가한 것으로 판단된다. 또한, 실리카흄을 5% 치환한 시험체의 경우, 고로슬래그 치환율이 증가함에 따라 상대적으로 큰 공극량은 감소하고 미세공극량이 증가함으로써 폭렬량 또한 증가하는 결과를 나타냈다. The method of concrete mix design used in this study aims to achieve the identical specified design strength, applying different types and replacement ratio of mineral admixtures and afterwards, fire tests were conducted using the standard time-temperature curve specified in the ASTM E119 to identify the influences of the types of mineral admixtures on the fire resistance performance of high strength concrete(HSC). The least spalling was observed in the test specimen containing blast furnace slag as a partial replacement of cement, while the most significant spalling phenomena were observed in the blast furnace slag test specimen that silica-fume was added in. In particular, the reasonable volume of spalling was observed when solely replaced by silica fume. However, the influence of the cement replacement by silica fume and blast furnace slag on the increases of spalling can be explained through blocked pores by the fine particles of silica fume, leading to decreases in permeability.