Results Of Fire Resistance Tests Research Articles

Thermal response of high-speed train multi-layer composite floor structure: Experimental and numerical analysis

This study examines the issue of fire resistance in multi-layer composite floor structures for high-speed trains. A standard test was conducted to evaluate the thermal insulation and integrity of the structure, and a 1-D numerical simulation model was established to calculate the fire resistance accurately. The fire resistance test results show that the aluminum profiles and glass wool played an important role in the fire resistance of the high-speed train floor structure. The upper surface temperature of the glass wool remained below 150 °C during the initial 30 min of the fire test, and the glass wool maintained its structural integrity for an additional 4.33 min after the aluminum profile was burnt through. This study validates the established model by comparing the simulation results with the standard structural fire resistance test result. The floor temperature distribution from the numerical simulation is consistent with the experimental results, and the error in integrity and thermal insulation is only 2.6 % and 5.4 % compared with the experimental value.

Fire Resistance of an Assembled Integrated Enclosure Panel System

Due to increasing economic development in recent years, large-scale prefabricated structures have been used for substations. However, the assembly of steel structures suffers from technical problems, such as the mismatch between the fire protection level of the main structure and the enclosure system. This paper proposes an assembled integrated enclosure panel system for covering and fireproofing steel structures, such as beams and columns, consisting of sandwich wall panels and autoclaved lightweight concrete (ALC) wall panels covering the main steel structure. Fire resistance tests were carried out for each part and the entire integrated enclosure panel system to fully investigate its fire resistance performance. ALC and gypsum were selected as the external fire protection materials for the sandwich wall panel test for theoretical analysis and fire resistance test. The fire resistance test results show that the designed solutions of sandwich wall panels and ALC panels covering steel beams and columns meet the fire protection requirements of the ISO-834 standard fire test. The proposed size scheme of the integrated enclosure panel system is an integrated sandwich wall panel composed of 50 mm thick ALC board + 50 mm thick rock wool layer + 50 mm thick ALC board and the integrated structure of 100 mm thick ALC board covering beams and columns. The designed U-shaped connectors between the wall panels are suitable for the assembled integrated enclosure panel system.

Fire behaviour of GFRP-reinforced concrete slab strips. Effect of straight and 90° bent tension lap splices

This paper presents results of fire resistance tests on concrete slab strips reinforced with ribbed glass fibre reinforced polymer (GFRP) bars, comprising continuous reinforcement or tension lap splices with different geometries (straight- and 90° bent-ends), overlap lengths and bar types. The type of reinforcement (material and surface finish), the rebar diameter and the concrete cover thickness were also assessed. It was shown that GFRP-reinforced concrete slabs with continuous reinforcement can endure over 180 min of fire exposure with considerably lower concrete covers than those currently recommended in design codes, provided that the rebars remain well-anchored in cool zones of the member. Slabs with straight-end splices failed due to debonding of the overlapped rebars after 19 to 39 min of fire exposure, depending on the type of bar and splice length. With 90° bent-end splices, the fire resistance significantly increased, up to 75 min, as they allowed anchoring the reinforcement in a cooler zone of the slab where bond was less degraded.

Weight Fraction Effect of Sugar Palm Fiber as Polypropylene-Elastomer Matrix Reinforcement on Fire Resistance of Hybrid Composite

Indonesia is one of the countries with abundant availability of palm fiber (Arenga pinnata), polypropylene (PP), elastomer. By utilizing these three types of materials, it is hoped that they can become new composite materials that have good physical properties and characteristics and are useful in engineering applications. PP and elastomer materials used in this study act as a composite matrix and are reinforced by palm fiber (Arenga pinnata). Composites are generally a new material by combining two or more different materials to produce a new material with better properties than the constituent material itself. This study aims to determine the value of the fire resistance of PP composites and elastomers with sugar palm fiber (Arenga pinnata) reinforcement with various weight fractions of 20 % (80:20), 30 % (70:30), and 40 % (60:40). Based on the fire resistance test results of hybrid polypropylene and elastomeric composites with sugar palm fiber reinforcement (Arenga pinnata) showed that the composite with a fraction of 20 % (80:20) had the lowest linear combustion rate of 0.128 mm/minute. In comparison, the composite with a weight fraction of 40 % (60:40) obtained the highest linear combustion rate of 0.202 mm/minute. For the weight loss rate test, the composite with a weight fraction of 20 % (80:20) got the highest result of 0.759 gram/minute, while the composite with a weight fraction of 40 % (60:40) got the lowest weight loss rate of 0.480 gram/minute.

Performance of insulated FRP-strengthened concrete flexural members under fire conditions

This paper presents the results of fire resistance tests on carbon fiber-reinforced polymer (CFRP) strengthened concrete flexural members, i.e., T-beams and slabs. The strengthened members were protected with fire insulation and tested under the combined effects of thermal and structural loading. The variables considered in the tests include the applied load level, extent of strengthening, and thickness of the fire insulation applied to the beams and slabs. Furthermore, a previously developed numerical model was validated against the data generated from the fire tests; subsequently, it was utilized to undertake a case study. Results from fire tests and numerical studies indicate that owing to the protection provided by the fire insulation, the insulated CFRP-strengthened beams and slabs can withstand four and three hours of standard fire exposure, respectively, under service load conditions. The insulation layer impedes the temperature rise in the member; therefore, the CFRP–concrete composite action remains active for a longer duration and the steel reinforcement temperature remains below 400°C, which in turn enhances the capacity of the beams and slabs.

Study on prediction method for the insulation of gypsum board using inclusive thermal conductivity in fire resistance tests

AbstractIn this study, a method for predicting the unexposed surface temperature of a wall is proposed based on the concept of “inclusive thermal conductivity,” which considers the heat and mass transfer of materials containing moisture. The inclusive thermal conductivity is estimated based on the results of temperature measurements obtained from actual fire resistance tests. The proposed method enables the estimation of material thermal conductivities that are difficult to assess using conventional methods. The inclusive thermal conductivity is affected by the deterioration and evaporation that occurs in the materials, which are estimated from the fire resistance test results. The unexposed surface temperature predictions for the gypsum boards of different thicknesses are numerically analyzed by changing the number of inclusive thermal conductivities. The inclusive thermal conductivity of the gypsum board increases as the temperature increases. The unexposed surface temperature prediction is affected by the exposed surface temperature of the fire resistance tests, and the prediction accuracy increases as the difference in the material thickness decreases. The exposed surface temperature obtained from the fire resistance test results influences the prediction of the unexposed surface temperature. The prediction accuracy of the numerical analysis using the inclusive thermal conductivity is confirmed to be practically sufficient.

The Results of Fire-Resistance Tests of Fragments of Load-Bearing Elements of Prefabricated Block-Modular Civil Defense Shelter

The Results of Fire-Resistance Tests of Fragments of Load-Bearing Elements of Prefabricated Block-Modular Civil Defense Shelter

Fire Insulation of Aluminum Glazed Partitions Depending on the Infill Solution of Framework Profiles

This paper presents the main problems related to the fire resistance of aluminium glazed partitions. It discusses technical solutions used in partition systems with a specific fire resistance class, as well as a procedure and the general principles of classification of fire resistance for structures of this type. Moreover, the paper presents the comparison of fire resistance test results of glazed partition test specimens, depending on the volume of insulation inserts placed inside the aluminium structure profiles. To made the comparison the specimens with the same transom - mullion structure were tested with two filling solutions - with same profiles filled only in the middle part and fully filled.

SANDWICH PANELS – BEHAVIOR IN FIRE BASED ON FIRE RESISTANCE TESTS

<p>Sandwich panel is the material that is easy and quickly to install. Basing on a great experience in the area of determination of the fire resistance class of construction building elements the authors describe the properties and behavior of building elements made of the sandwich panels exposed to fire. The article presents the results of fire resistance tests carried out in accordance with EN 1364-1 non-bearing walls made of sandwich panels with use of different cores.</p>The following parameters were analyzed: temperature rise on unexposed side (I – thermal insulation), integrity (E) depending on the orientations and on the width of the sandwich panels, deflection depending on the thickness of the boards. Conclusions were made on the base of the analysis from fire resistance tests.

FIRE RESISTANCE TESTS OF ALUMINIUM GLAZED PARTITIONS, Results comparison

This paper discusses the main problems related to the fire resistance of aluminium glazed partitions, including the tests methodology and way of classification of this type of elements. Moreover, the paper presents the comparison of fire resistance test results of glazed partition test specimens, depending on the number of insulation inserts placed inside the aluminium structure profiles. To made the comparison the specimens with the same transom – mullion structure were tested in two configurations and with two filling solutions – with profiles filled only in the middle part and with fully filled profiles.

FIRE RESISTANCE OF ALUMINIUM GLAZED CURTAIN WALLS, Test results comparison depending on the side of fire exposure

This paper discusses the main issues related to the fire resistance of aluminium glazed curtain walls including the tests methodology and way of classification of this type of building elements. Moreover, the paper presents the comparison of fire resistance test results of large test specimens of curtain walls in full configuration depending on the side of fire exposure. Temperature rises have been compared on unexposed surface of the curtain walls tested for standard and external fire exposure. To made the comparison four test specimens of glazed aluminium curtain walls in full configuration, were tested. Curtain walls had the same transom – mullion structure. Two test specimens were tested for external fire exposure, and two for standard fire exposure. Dimensions of exposed surfaces were 5000 x 4500 mm (width x height) for external fire exposure and 5000 x 4800 mm (width x height) for internal fire exposure.

Fire behaviour of thermally insulated RC beams strengthened with NSM-CFRP strips: Experimental study

This paper presents the results of fire resistance tests on reinforced concrete (RC) beams flexurally strengthened with carbon fibre reinforced polymer (CFRP) strips installed according to the near surface mounted (NSM) technique using two different adhesives. The beams were simultaneously subjected to a service load and the ISO 834 standard fire. Different fire protection schemes were studied, comprising a thinner insulation layer along the bottom soffit of the beams and a thicker one at the CFRP anchorage zones. The main objectives of this paper were (i) to understand in further depth the fire behaviour of NSM-strengthened RC beams, in particular the structural effectiveness of the strengthening system during fire, (ii) to evaluate the efficiency of the above-mentioned fire protection strategy in extending the CFRP mechanical contribution during fire, and (iii) to compare the fire performance of the NSM-strengthening system with that of the alternative externally bonded reinforcement (EBR) technique, recently investigated under similar test conditions. The results obtained showed that using the adopted insulation schemes (i.e., thicker insulation at the anchorage zone and thinner insulation in the current zone), even after the CFRP-concrete bond is highly damaged in the central zone of the beams, the strengthening system is able to retain its structural effectiveness through a cable mechanism: for insulation thicknesses of 25 mm (current zone) and 50 mm (anchorage zones), the fire resistance of the strengthening system was extended up to 114 min. The loss of effectiveness of the CFRP system occurred when the average temperature in the adhesive at the CFRP anchorage zones attained values ranging from 2.2 to 5.6 times its glass transition temperature (Tg). The comparison with the EBR-strengthened beams confirmed the much better performance of the NSM strengthening.

화재피해를 입은 철근콘크리트 기둥의 잔존강도 추정 및 내화성능 요인 분석

본 연구에서는 화재피해를 입은 철근콘크리트 기둥을 대상으로 실험 및 해석적 방법에 의해 잔존강도를 추정하고 내화성능에 영향을 미치는 요인을 분석하였다. 철근콘크리트 기둥의 강도저감율과 내화성능 예측을 위해 간편 계산모델인 EN 1992-1-2의 <TEX>$500^{\circ}C$</TEX> 등온선법을 이용하였다. 철근콘크리트 기둥은 순수 축압축력을 받는 것으로 가정하고 표준 내화실험으로부터 얻은 기둥 내부 온도자료를 활용하여 표준화재에 180분간 노출된 철근콘크리트 기둥의 잔존강도율을 산출하였다. 아울러 콘크리트 강도, 피복두께, 단면크기, 잔존 유효단면적 등 철근콘크리트 부재 내화성능 영향요인의 상관관계를 분석하였다. 본 연구를 통해 추정한 철근 콘크리트 기둥의 잔존강도율은 내화성능설계를 위한 계수하중 설정 및 하중비 설정에 중요하게 활용될 수 있을 것으로 사료된다. This study aims to estimate the residual strength by experimental and analytic method and analyze the elements affecting fire resistant performance of reinfored concrete column. For predicting strength reduction rate and fire resistant rate of reinforced concrete column <TEX>$500^{\circ}C$</TEX> isotherm method of EN 1992-1-2, a simplified calculation method, was used. The residual strength rate of reinforced concrete column, which is exposed to standard fire for 180 minute and assumed to bear the pure axial compressive force, was calculated with inner temperature data achieved from fire resistance test results. Further, the analysis of relations of fire resistance rate affecting elements for reinforced concrete member were performed. The residual strength rate of reinforced concrete column estimated in this study may be used as a significant information for establishing fire load factor and load ratio on performance based fire resistant design.

Fire resistance of walls made of soil‐cement and Kraftterra compressed earth blocks

SUMMARYThis study presents the results of fire resistance tests on walls made of soil‐cement and Kraftterra compressed earth blocks (CEBs). The purpose of this work was to evaluate and compare the fire resistance of CEB walls with and without cellulose pulp derived from the recycling of cement sacks. This article describes the Kraftterra mixture and its production processes as well as the fire resistance test campaign. The fire resistance performance of CEB walls produced with Kraftterra and soil‐cement blocks is analysed. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Experimental Research on the Load-Bearing Capacity of Partially Encased Steel Columns Under Fire Conditions

The composite steel and concrete columns are known to have enhanced fire behaviour when compared with bare steel columns. However there are still aspects that must be clarified, as the influence of the building surrounding structure on the fire resistance of the columns. In this paper, the results of fire resistance tests on partially encased steel columns carried out with two different experimental systems are compared. In one of the experimental systems, the building surrounding structure is materialised by a steel restraining frame, and in the other is performed by the so-called substructuring method. Due to the concept of hybrid substructuring, the entire building is decomposed in two parts: one is represented by the building element under test, whereas the remaining building is simulated numerically in a computer. The main conclusion drawn from this work was that the surrounding structure has a major influence in the development of axial forces in the test columns. Moreover, it was observed that the higher the non-dimensional axial restraint ratio the lower the critical time of the columns.

Fire Behaviour of Tropical and European Wood and Fire Resistance of Fire Doors Made of this Wood

In the building industry, there is currently a significant lack of information on fire resistance properties of room separation elements made of tropical wood species. The objective of the present study is to fill this gap by investigating the fire behaviour of tropical wood species and subsequently assessing the fire resistance of elements made of this material. In particular, the prime target was to find easy to measure parameters which correlate with both the charring rate and the deflection, the latter caused by fire induced rapid dehumidification. Further, the so found parameters have been investigated for suitability as reliable predictors for fire resistance of fire doors when tropical wood is used as substitute for European native wood. A series of measurements were carried out for tropical and European wood species. Beam deflection and charring rate as well as the fire resistance of doors were measured in standard fire (ISO 834-1). In addition, the oxygen permeability index (OPI) of wood, which appears to have a strong correlation with the charring rate, was measured. It is shown that in consideration of fire resistance both the charring rate and the deflection have to be addressed when tropical wood is used as substitute for European native wood. Finally, it is clearly confirmed that a single parameter such as wood density is not reliable to assess the substitution of an alternative wood species for a species on which fire resistance test results are available.

Predicting the Fire Resistance of Wood–Steel–Wood Timber Connections

This paper presents an investigation on the fire performance of wood–steel–wood timber connections with slotted-in steel plates. In the first part, a three-dimensional thermal model was employed that uses the finite element method to analyze heat transfer within timber connections exposed to the standard fire. The temperature-related properties were obtained from the literature and imported into the thermal model. A validation of the proposed thermal model was achieved by comparing predicted temperatures with experimental results. In the next phase, a reduction in the embedding strength method was adopted to estimate the load-carrying capacity of connections in fire. Based on the temperature profiles within the connection calculated by the thermal model, the reduction of the embedding strength was determined and used to calculate the load capacity at elevated temperatures. Furthermore, a formula was proposed to evaluate the fire resistance rating of timber connections and compared with the results of fire resistance tests. The parameters considered included the load level, fastener diameter and wood member thickness.

Effect of Heat Losses on Fire Resistance Test Results for Metal

The effect of heat losses on the fire resistance of a flat metal plate tested in a standard fire regime is examined. The dependence of the temperature dynamics of the plate with and without a coating on the thermophysical properties of the insulation on exposure to fire heat loading is studied numerically. The results of the study indicate the need for using a coupled formulation of the problem and standardizing the type and thermophysical properties of the thermal-insulation material for a correct modeling and testing of the heat and fire protection of the metal plate, especially in the case of a small plate thickness. Integral criteria are proposed to characterize the heat losses and insulation efficiency on the rear surface of the plate.

Fire Safety Performance of Japanese Traditional Wood/Soil Walls and Implications for the Restoration of Historic Buildings in Urban Districts

Grass-root research activities to clarify fire safety performance of Japanese traditional wooden construction are introduced. The activities aim to resolve conflict between the restoration of historic buildings and the reduction of risk and hazard of urban fires. Among various activities, scope and results of fire resistance tests on traditional soil wall assemblies supported by timber frame are reported in detail. The test results indicate an encouraging prospect for the rational fire safety assessment of historic buildings and further development of fire-safe traditional constructions for the restoration of historic buildings and historic urban districts.

F210 IS0834に基づく積層型中空耐火壁の加熱シミュレーション(オーガナイズドセッション17 : 材料およびデバイス製造の熱工学)

The Building Standards Act designates fire zones and semi-fire zones for the purpose of decreasing the number of damages caused by serious city fires, and requires fireproof construction or fire protection for buildings. A fire resistance test is one of the methods of estimating the performance of fireproof construction, and is done by using the ISO method or the JIS method. However, these tests require large scale and expensive appliances, much preparation time, and the expenses for making specimens are huge. To cope with this issue, we have been developing numerical simulation codes for predicting mutual relation between the fireproof construction and the fire resistance test results. In this study the results of numerical simulation of the multi-layered cavity wall, which is one of the fundamental structures in building construction, is shown.