No / This paper presents experimental results of temperature distribution in fire in four typical types of steel-concrete composite joint (web cleat, fin plate, flush endplate and flexible endplate) with different fire-protection schemes. The test specimens were unloaded and the steelwork of each joint assembly was exposed to a standard fire condition [ISO 834, 1975: Fire Resistance Tests, Elements of Building Construction, International Organization for Standardization, Geneva] in a furnace. In total, 14 tests were conducted, including 4 tests without any fire protection and 10 tests with different schemes of fire protection. The main objective of these tests was to investigate the effects of three practical fire-protection schemes as alternatives to full fire protection of the entire joint assembly. The three alternative methods of fire protection were: (1) protecting a segment, instead of the entire length, of the beams; (2) unprotected bolts and (3) protecting the columns only. The main results of these tests are: (1) if all the steel work (excluding the bolts) in the joint assembly was protected, whether or not protecting the bolts had very little effect on temperatures in the protected steelwork other than the bolts. The bolt temperatures were higher if they were not protected than if they were protected, but the unprotected bolt temperatures in a joint with fire protection to other steelwork were much lower than bolt temperatures in a totally unprotected joint; (2) as far as joint temperatures are concerned, protecting a segment of 400 mm of the beam was sufficient to achieve full protection and (3) if only the column was protected, only the joint components that were in the immediate vicinity of the column (such as welds) developed noticeably lower temperatures than if the joint assembly was unprotected, but due to heat conduction from the unprotected steel beams, these temperature values were much higher than if the joint assembly was protected. Furthermore, the column temperatures in the joint region were much higher than the protected column temperatures.

The expansion ratio (defined as the ratio of the expanded thickness to the original thickness) of intumescent coatings is the most important quantity that determines their fire protection performance. This thesis explores two possible methods of predicting intumescent coating expansion: an analytical method, and a detailed numerical simulation method using Smoothed Particle Hydrodynamics (SPH).The analytical method is based on a cell-model and predicts bubble growth due to pressure increase in viscous liquid with constant viscosity. It has been extended to non-uniform temperature field and temperature-dependent viscosity of intumescent melt. Accuracy of this extended analytical method is assessed by comparison against the cone calorimeter and furnace fire tests on intumescent coating protected steel plates with different intumescent coating thicknesses, steel plate thicknesses, and heating conditions. The extended analytical method is then used to investigate how intumescent coating expansion and intumescent coating effective thermal conductivity are affected by changing the coating thickness, the steel thickness and the fire condition (including smouldering fire). The main conclusion is that the expansion ratio decreases as the rate of heating increases. Therefore, the intumescent coating properties obtained from the Standard fire exposure may be safely used for slower realistic fires, but would produce unsafe results for faster fires. The second method explores the potential of a meshless numerical simulation: Smoothed Particle Hydrodynamics (SPH). SPH modelling of intumescent coating expansion has been implemented using the SPHysics FORTRAN open-source code as a platform. To check the validity of this modelling method, the modelling results are compared against theoretical solutions for surface tension (Young-Laplace theorem), and available numerical and analytical solutions for bubble expansion. A new algorithm for representing the mass transfer of gas into the bubble using SPH particle insertion and particle shifting scheme is presented to simulate the bubble expansion process. Close agreement with an analytical solution for the initial bubble expansion rate computed by SPH is obtained. Whilst this research has demonstrated the potential of using SPH to numerically simulate intumescent coating expansion, it has also revealed significant challenges that should be overcome to make SPH a feasible method to simulate intumescent coating expansion. The main challenges include:• Simulating gas-polymer flows when expansion is occurring where there are vastly different properties of these two fluids with a density ratio of about 1000. This high density ratio may easily cause numerical pressure noise, especially at the liquid-gas interface.• Extremely high computational cost necessary to achieve sufficient accuracy by using a large number of particles (higher resolution), especially for the multi-phase SPH program, and very small time step for the lighter fluid (air). • The behaviour of intumescent coatings involves expansion ratios on the order of 10-100 with thousands of bubbles which grow, merge and burst. Based on the results of this exploratory research, future improvements are outlined to further develop the SPH simulation method.

Intumescent coating fire protection on steel structures is becoming widely popular in the UK and Europe. The current assessment for the fire protection performance method using the standard fire resistance tests is not accurate, owing to the reactive behaviour of intumescent coating at elevated temperature. Moreover, the available intumescent coating temperature assessment method provided in the Eurocode for structural steel at elevated temperature does not incorporate the steel beam's behaviour and/or assessment for partial protection and/or damaged protection. The research work presented provides additional information. on the assessment of partial and/or damaged intumescent coating at elevated temperature. In the scope of the investigation on the thermal conductivity of intumescent coating, it was found that the computed average thermal conductivity was marginally sensitive to the density and emissivity at elevated temperature. However, the thermal conductivity was found to be reasonably sensitive to the differences in initial dft's (dry film thicknesses). In this research, a numerical model was developed using ABAQUS to mimic actual indicative test scenarios to predict and establish the temperature distribution and the structural fire resistance of partial and/or damaged intumescent coating at elevated temperatures. Intumescent coating actively shields when the charring process occurs when the surface temperature reaches approximately 250°C to 350°C. Maximum deflection and deflection failure times for each damage scenario were analyzed by applying specified loading conditions. It was also found that the structural fire resistance failure mode of intumescent coating on protected steel beams was particularly sensitive to the applied boundary conditions. Careful selection of nodes in the element was necessary to avoid numerical instability and unexpected numerical error during analysis. An assessment of various numerical models subjected to a-standard fire with partially protected 1 mm intumescent coating was analysed using ABAQUS. An available unprotected test result was used as a benchmark. The outcome suggests that the fire resistances of the beams were found to be sensitive to the location of the partial and/or damage protection. The overall fire resistance behaviour of intumescent coating at elevated temperature was summarized in a 'typical deflection regression' curve. An extensive parametric analysis was performed on localized intumescent coating damage with various intumescent coating thicknesses between 0.5mm to 2.0mm. It was found that the average deflection was linear for the first 30 mins of exposure for all the variables, damage locations and intumescent thicknesses. It was concluded that a thicker layered intumescent coating may not be a better insulator or be compared to a much less thick intumescent coating at elevated temperature. The use of passive fire protection, however, does enhance the overall fire resistance of the steel beam, in contrast to a naked steel structure. The research work investigated the intumescent coating behaviour with different aspects of protection and damage and the outcome of the assessment provided a robust guide and additional understanding of the performance of intumescent coating at elevated temperature.

No description available.

The ASTM E119 is a large-scale test used to qualify assemblies for fire resistance, including heat transmission and structural integrity. The test requires specialized furnaces and full-scale assemblies that are 3.0 m (10 ft) or more on each side, making it very expensive to perform. In this study, we investigated the feasibility of the scaling methodology for a reduced-scale fire resistance test on different types of wood-based structures, specifically commercially available intumescent coating applied onto wood and bolted lap joints in wood. We build upon a previously developed scaling methodology for wood and gypsum boards, which integrated geometric scaling, Fourier number time scaling, and furnace boundary condition matching. Intumescent coating presents a particular challenge in scaling in that it expands when exposed to fire conditions. To account for this expansion, we identified a relationship between initial dry film thickness and final expanded thickness through cone calorimeter tests and integrated it into a modified scaling methodology. This approach was then validated through fire exposure tests in furnace on wood samples painted with intumescent coating at full, half, and quarter scales. Finally, we demonstrated the scaling laws for joints under combined thermo-structural loading, by subjecting wood-based half-lap joint samples to combined bending and thermal loading at half and quarter scale. The samples were subjected to static three-point bending with the load scaled to achieve structural similitude, while simultaneously being exposed to a scaled fire exposure on the bottom surface. Our study provides insights into the practical application of scaling methodology for testing the fire resistance of joints and fire-resistant coated wood, paving the way for more cost-effective and quicker fire testing for the wood-based composite industry. / Master of Science / The ASTM E119 is a critical test standard that evaluates the fire resistance of various building materials, including wood-based structures. However, the standard tests are quite expensive due to the need for specialized equipment and large-scale samples. In this study, we explored the potential of using a scaled-down fire resistance test on different types of wood-based materials, including commercially available fire-resistant coated wood and joints. We built on existing scaling methods for wood and gypsum boards and adapted it to account for the unique properties of intumescent coating - a fire-resistant material that expands when exposed to high temperatures. By conducting a series of tests, we developed a modified scaling approach to accommodate the expansion of the coating. We then validated this new method by performing fire exposure tests at various scales on wood samples coated with intumescent coating. Finally, we adapted the scaling methods to account for wood based bolted joints. We tested the fire resistance of wood-based half-lap joints under combined heat and structural stress at smaller scales. Our study offers valuable insights into a more cost-effective and efficient method for testing fire resistance in wood-based structures. By providing a reliable scaling approach for fire-resistant coated wood and joints, our work has the potential to make fire testing more accessible for the wood composite industry, ultimately leading to safer and better-performing buildings.

No / Based on temperatures measured in steel joints with different extents of fire protection, this paper proposes a simple method to calculate temperatures in steel joints with partial intumescent coating fire protection. The method combines the simple temperature calculation methods in EN 1993-1-2 (Committee of European Normalisation CEN, Eurocode 3: design of steel structures—part 1-2: general rules—structural fire design, 2005) for unprotected and protected steel structures through the introduction of an exposure factor, which is the ratio of the unprotected surface area of the joint region to the total surface area of the joint area. Using the measured temperatures for fully protected steel joints, this paper first extracts the effective thermal conductivity of the intumescent coating used in the fire tests. Afterwards, this paper presents validation results based on fire test results on joints with partial fire protection. Finally, this paper presents methods to calculate the exposure factor for different types of partially fire protected steel joints.

Baigiamajame magistro darbe nagrinėjamas priešgaisrinės išsipučiančios dangos porėto ir nedegių liekanų termiškai stabilaus sluoksnio sudarymo principai. Aprašomi užpildai bei kiti komponentai gerinantys dangos termoizoliacines savybes. Taip pat pateikta įvairių užpildų įtaką sudarant apsauginį dažų sluoksnį. Be to, darbe yra aprašyti minimalaus priešgaisrinės dangos sluoksnio, reikalingo plieno konstrukcijoms gaisro metu apsaugoti, skaičiavimai. Metodinėje-tiriamojoje darbo dalyje pateikta priešgaisrinės dangos bandymo atlikimo tvarka ir įranga, šilumos laidumo skaičiavimo metodika. Išnagrinėta koreliacinės-regresinės analizės vertinimo metodika. Praktinėje darbo dalyje analizuojamos priešgaisrinės dangos šilumos laidumo ir dangos termoizoliacinio sluoksnio padidėjimo priklausomybė nuo skirtingai didėjančių gaisro temperatūrų. Taip pat gautiems šilumos laidumo rezultatams atliekama koreliacinė-regresinė analizė. Darbą sudaro 5 dalys: įvadas, analitinė dalis, metodinė-tiriamoji dalis, išvados, literatūros sąrašas. / In the analytical part of this Thesis, the principals of fire resistance intumescent coatings foam and thermally stable char layer forming is presented. The fillers and other components for improving surface thermal properties are discussed. As well as a variety of fillers influence the protective coating analyses. In addition, the work is described the minimum fire protection coating layer of steel structures required for fire protection calculations. In the project part of this Thesis, the procedures and equipment, the heat conduction calculation is given. Moreover, the Thesis fire surface thermal conductivity and thermal insulation coating layer increases dependence on the different ways of rising temperatures in the fire analyses. It is also obtained the result of heat conduction by correlation-regression analysis. Structure: introduction, analytical part, the research part, conclusions and references.