Made available in DSpace on 2014-06-11T19:35:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-03Bitstream added on 2014-06-13T19:46:23Z : No. of bitstreams: 1 silva_mrr_dr_ilha.pdf: 1608387 bytes, checksum: 1a7a08a72b66b63f3bd70928d1038445 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O arroz é uma das culturas que mais se destaca na produção mundial, responde ao uso de tecnologias, porém seu cultivo em terras altas apresenta problema de acamamento, dificultando ou impossibilitando a colheita mecânica. O objetivo do trabalho foi estudar o efeito do regulador de crescimento etil-trinexapac e diferentes densidades de semeadura do arroz de terras altas, cultivar BRS Primavera, nos municípios de Fernandópolis – SP e Selvíria – MS, visando reduzir a altura e diminuir o acamamento das plantas de arroz. O experimento foi conduzido no ano agrícola 2008/09, na Fazenda de Ensino e Pesquisa da Universidade Camilo Castelo Branco, Campus de Fernandópolis – SP, e na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia, Campus Ilha Solteira - UNESP, localizada no município de Selvíria – MS. O delineamento experimental utilizado foi blocos ao acaso, disposto em esquema fatorial 5 x 2, com quatro repetições. Os tratamentos foram constituídos por cinco densidades de semeadura (100, 150, 200, 250 e 300 sementes viáveis por metro quadrado), com e sem aplicação de regulador de crescimento. O aumento da densidade de semeadura interferiu negativamente na produtividade de grãos de arroz apenas para a primeira semeadura em Selvíria – MS. A aplicação do etil-trinexapac resultou em plantas com menor altura e acamamento e, reduziu a produtividade de grãos da cultura do arroz para as duas localidades. Apesar da aplicação de etil-trinexapac reduzir a produtividade de grãos, seu uso em cultivares com tendência ao acamamento é interessante por possibilitar a colheita mecanizada, o que não é possível em áreas com plantas acamadas. O etil-trinexapac constitui uma ferramenta importante no manejo da cultura do arroz de terras altas, mas que ainda influencia nos componentes vegetativos e na produtividade e, não interfere no rendimento industrial do cultivar BRS Primavera / Rice crop is highlighted around the world production, its responds to technology. However its cultivation in uplands presents problems of lodging, making it difficult or almost impossible the mechanical harvest. The goal of this research was to study the effect of growth regulators ethyl-trinexapac on sowing densities on upland rice, growing BRS Primavera, in Fernandópolis – SP and Selvíria – MS, aiming to reduce plant height and to prevent possible lodging of the rice plants. The experiment started in the agricultural year of 2008/2009, on the Experimental Farm of Camilo Castelo Branco University, Campus of Fernandópolis, SP, and on the Experimental Farm of Engineering College, Campus of Iha Solteira (UNESP), located in the municipal district of Selvíria, MS. The experimental design used was randomized blocks with treatments in factorial arrangement 5 x 2. There were four repetitions. The treatments were made of five combination of sowing densities (100, 150, 200, 250 and 300 seeds per square meter), with and without the use of growth regulator ethyltrinexapac. Increased seeding rate had a negative influence on grain yield of rice only for the first sowing in Selvíria, MS. The application of ethyl-trinexapac resulted in plants with reduced height and lodging and reduced grain yield of rice for both locations. Despite the application of ethyl-trinexapac reduce grain yield, its use in cultivars prone to lodging is interesting because they allow mechanized harvesting, which is not possible in areas with lodged plants. Ethyl-trinexapac is an important tool in the management of upland rice culture, but it still influences the vegetative components and productivity, and it does not interfere with the performance of industrial BRS Primavera

L’objectif de ce travail a consisté à développer un revêtement polyuréthane (PU) ignifugeant à partir de caoutchouc naturel. Pour ce faire, deux types de diols ont été utilisés. Un oligoisoprène hydroxytéléchélique a été tout d’abord synthétisé et utilisé comme segment souple. Par ailleurs, un second oligomère phosphorylé, dont les groupements phosphonate ou phosphate sont connus pour offrir des propriétés retardatrices de flamme, et possédant une extrémité diol a été réalisé afin de servir d’extenseur de chaine au cours du procédé one shot d’obtention des revêtements. Ces oligophosphonates ou phosphates ont été obtenus quant à eux selon un procédé de polymérisation radicalaire contrôlé de type RAFT à partir de monomères diethyl (acryloyloxymethyl) phosphonate (DEAMP) et 2-acryloyloxyethyldiethylphosphate (ADEP) afin d'accéder à deux gammes de masses strictes (n~13 and n~21 ) et des dispersités étroites (Ð<1.2). Ces polymères ont été entièrementcaractérisés par RMN 1H, 31P, SEC et spectrométrie Maldi TOF et utilisés en synthèse de polyuréthanes selon deux procédés appelés additif et réactif. Les propriétés physicochimiques et mécaniques des matériaux PU synthétisés ont été comparés à ceux de matériaux PU incorporant selon les mêmes approches une petite molécule phosphorylée, afin de traduire les effets spécifiques de ces oligomères. Les revêtements polyuréthane synthétisés ont été caractérisés par FTIR et spectroscopie Raman afin de mesurer la dispersion des oligomères phosphorés au sein de la matrice polymère. En outre, les propriétés physicochimiques et notamment les propriétés ignifugeante ont été évaluées par TGA, DSC et LOI. En complément, les propriétés mécaniques ont été elles aussi évaluées (élongation à rupture, module, dureté et scratch test). Une étude de mapping par spectroscopie Raman a révélé une meilleure dispersion des additifs dans un matériau obtenu selon l’approche réactive, où l’oligomère phosphorylé est lié de manière covalente au squelette du Polyuréthane. De la même façon, cette dispersion apparaîtplus homogène pour l’utilisation d’un oligomère de chaine plus courte (n=13). Les propriétés ignifugeantes ont été démontrées grâce aux caractérisations TGA et DSC où la première étape de décomposition est retardée quels que soient les pourcentages d’oligomères incorporés à la matrice (1, 5 ou 8%). En outre, il s’avère que les mesures LOI démontrent un maximum proche de 30% pour un pourcentage d’oligomère de 8%, valeur très notablement supérieure à celle de l’additif de comparaison. Concernant les propriétés mécaniques, l’incorporation d’oligomères phosphorylés entraîne une augmentation du module et de la dureté et une diminution de la résistance à l’abrasion. Les valeurs d’élongation à rupture sont cependant très similaires, quelles que soient les formulations testées. Néanmoins, ces propriétés apparaissent très supérieures à celles de la matrice standard, démontrant une plus grande efficacité d’oligomères phosphorylés par comparaison avec une petite molécule de type phosphate ou phosphonate. Ces résultats encourageant laissent entrevoir une perspective d’application industrielle de cette méthodologie vers la production de caoutchoucs ignifugeants. / The aim of this research was to develop polyurethane (PU) coating from Natural Rubber (NR) presenting Flame Retardant (FR) properties. For this purpose, two kinds of diols were used. Hydroxytelechelic oligoisoprenes were firstly synthesized from Natural Rubber (NR) and used as softsegment. Secondly, diol chain end phosphorylated oligophosphonates or oligophosphates were synthesised that would cater as chain extender during the polyurethane synthesis one shot process. Such Phosphorylated oligomer was synthesized by RAFT polymerization of diethyl (acryloyloxymethyl) phosphonate (DEAMP) and 2-acryloyloxyethyl diethylphosphate (ADEP) monomer. A new trithiocarbonate based RAFT agent was synthesized (2-(dihydroxypropan-2-yloxy)carbonyl trithiocarbonate). This RAFT agent was used to polymerize each monomer with welldefinedmolecular weight and narrow dispersities (Đ<1.2). The polymer was well characterised by 1H, 31PNMR, SEC and Maldi TOF. The oligomers were synthesised with two different chain lengths, n≈13 andn≈21 to be used as additive and reactive FR in polyurethane films. As a reference molecule, a phosphatediol was synthesized to be used as a pendent group in polyurethane synthesis.Polyurethane films were fully characterised using FTIR, Raman spectroscopy, TGA, DSC and LOI.The mechanical properties were furthermore evaluated such as elongation at break, modulus, hardnessand scratch test. Polyurethanes with 1, 5, and 8% w/w of the phosphorylated oligomer were preparedaccording two different pathways so called additive or reactive. The main difference consists in thecovalent attachment of the phosphorylated oligomer to the PU backbone in the reactive pathway whilein the additive process, the oligomers are only physically incorporated in the PU. Raman mappingcharacterizations on the different films reveal a better homogeneous distribution of shortphosphorylated oligomer chains using a reactive pathways compared to the additive pathway as well asthe use of longer chains. Moreover TGA Analysis showed lower decomposition temperature on the firststep and an increased decomposition temperature on the second step of all phosphorylated treatedPUs. This indicates char formation from FR oligomer at lower temperature increases the decompositiontemperature on the second step. LOI measurements showed a maximum of 28.2% with shorterphosphate based oligomers added via reactive pathway at 8%w/w ratio.The mechanical properties of PU with phosphorylated oligomer gave similar elongation at breakbetween additive and reactive pathway. Compared to standard PU, the incorporation of the phosphorylated oligomer showed a decrease in scratch resistance and an increase in modulus and hardness. However, these oligomers (additive and reactive) performed better when compared withsmall molecule added as additive fillers. As a perspective, these phosphorylated oligomers on its own,with low Tg values (≈ -30oC), could be used in dry rubber FR application.

abstract: Flame retardants (FRs) are applied to variety of consumer products such as textiles and polymers for fire prevention and fire safety. Substantial research is ongoing to replace traditional FRs with alternative materials that are less toxic, present higher flame retardancy and result in lower overall exposure as there are potential health concerns in case of exposure to popular FRs. Carbonaceous nanomaterials (CNMs) such as carbon nanotubes (CNTs) and graphene oxide (GO) have been studied and applied to polymer composites and electronics extensively due to their remarkable properties. Hence CNMs are considered as potential alternative materials that present high flame retardancy. In this research, different kinds of CNMs coatings on polyester fabric are produced and evaluated for their use as flame retardants. To monitor the mass loading of CNMs coated on the fabric, a two-step analytical method for quantifying CNMs embedded in polymer composites was developed. This method consisted of polymer dissolution process using organic solvents followed by subsequent programmed thermal analysis (PTA). This quantification technique was applicable to CNTs with and without high metal impurities in a broad range of polymers. Various types of CNMs were coated on polyester fabric and the efficacy of coatings as flame retardant was evaluated. The oxygen content of CNMs emerged as a critical parameter impacting flame retardancy with higher oxygen content resulting in less FR efficacy. The most performant nanomaterials, multi-walled carbon nanotubes (MWCNTs) and amine functionalized multi-walled carbon nantoubes (NH2-MWCNT) showed similar FR properties to current flame retardants with low mass loading (0.18 g/m2) and hence are promising alternatives that warrant further investigation. Chemical/physical modification of MWCNTs was conducted to produce well-dispersed MWCNT solutions without involving oxygen for uniform FR coating. The MWCNTs coating was studied to evaluate the durability of the coating and the impact on the efficacy during use phase by conducting mechanical abrasion and washing test. Approximately 50% and 40% of MWCNTs were released from 1 set of mechanical abrasion and washing test respectively. The losses during simulated usage impacted the flame retardancy negatively. / Dissertation/Thesis / Doctoral Dissertation Materials Science and Engineering 2018

O PVC é um dos principais polímeros termoplásticos da atualidade graças à sua grande versatilidade. Entretanto, uma de suas características é a baixa estabilidade térmica, sendo necessário o emprego de aditivos em sua estrutura. Uma das maiores preocupações mundiais é a segurança, sendo que muitos produtos levam proteção anti-chama em sua composição. Entre os vários agentes retardadores de chama a grafite aparece como um material promissor e pouco estudado. No presente trabalho foi estudada uma série de grafites com propriedades anti-chama oriundas de óxido de grafite \"flake\". O óxido de grafite foi submetido a vários tratamentos térmicos em atmosfera para a obtenção de grafites expandidas. O comportamento anti-chama dessas grafites foi testado adicionando-se 20% em peso no PVC. Membranas desses compósitos foram preparadas utilizando-se um \"doctor blade\". Os compósitos de grafites produzidas foram caracterizados por microscopia de varredura eletrônica e análise térmica. Isotermas de adsorção/dessorção de N2 também foram coletadas para determinação de área superficial específica e distribuição de poros. A grafite com melhores propriedades anti-chama foi aquela obtida em temperatura mais elevada, 900oC, ou seja, a grafite com mais elevada área superficial específica e com maior capacidade de produção de fuligem. / PVC is one of the most important thermoplastic polymers because of its versatility. However, like other polymers, for many technological uses, there is a need to enhance its thermal stability. Security is a global concern, so, the use of some fire retardants is required in polymer composites. Expanded graphite appears as a cleaner type of fire retardants, not well known yet. In the present work, expanded graphite obtained from the graphite oxide was studied. It were prepared PVC composite-membranes with 20 weight % of expanded graphite employing Doctor Blade. The samples were characterized by scanning electron microscope, thermogravimetric analysis and N2 adsorption/desorption isotherms were also collected for the determination of specific surface area and porous distribuition. The results show that the best fire retardant behaviour was achieved by the expanded graphite at 900oC, the graphite with the higher specific surface area and with the largest capacity of soot production.

Tris(1-chloro-2-propyl) phosphate (TCPP) and tris(1,3-dichloro-2-propyl) phosphate (TDCPP) are added to polyurethane foams in a variety of industrial and consumer products to prevent flame ignition. The gradual release of these flame retardants (FRs) from such products leads to contamination of various abiotic and biotic media, including wild birds. Recent studies demonstrated endocrine-disrupting effects of TCPP and TDCPP, including alteration of circulating thyroid hormone (TH) levels. The TH-pathway is essential for normal growth and development in birds. There are limited data on the toxicological effects of TCPP and TDCPP in avian species and, prior to this work, no study has examined their effects in avian embryos. This M.Sc. thesis investigates the developmental, molecular and biochemical effects of TCPP and TDCPP in chicken (Gallus gallus domesticus) embryos via egg injection studies. TCPP delayed pipping at doses ≥9.24 μg/g, both TCPP and TDCPP reduced embryo growth at the highest dose (51.6 μg TCPP/g and 45 μg TDCPP/g), and TDCPP decreased free plasma thyroxine and gallbladder size at 7.64 μg/g and 45 μg/g, respectively. Real-time reverse transcription polymerase chain reaction was used to measure changes in mRNA levels of hepatic genes that were responsive to these FRs in a previous in vitro study. TCPP dysregulated the expression of TH-responsive genes and xenobiotic metabolizing enzymes (cytochrome P450s; CYPs), whereas TDCPP only affected CYPs. Less than 1% of the administered TCPP or TDCPP was detected in egg contents following 19 days of incubation, indicating extensive metabolism of the parent compounds. DNA microarrays were used to perform a global transcriptional analysis on liver samples from embryos that exhibited adverse effects following TDCPP injection. 47 differentially expressed genes were identified at the 45 μg/g dose. Functional analysis revealed that immune function and lipid and steroid metabolism were major targets of TDCPP toxicity and indicated a state of cholestatic liver/biliary fibrosis. Since the TH-pathway is a key regulator of metabolic homeostasis, its disruption early in development is a potential cause of the observed adverse effects. This thesis demonstrates, for the first time, developmental and endocrine-disrupting effects of TCPP and TDCPP in an avian species and attempts to link phenotypic changes to molecular-level disruptions in hopes to improve the understanding of their modes of action.

Depuis Juillet 2008, l'union européenne bannit une grande partie des retardateurs de flamme halogénés actuellement sur le marché pour des problèmes environnementaux. Les produits phosphorés s'avèrent une alternative prometteuse. Dans le cadre de ma thèse, nous décrivons la synthèse de monomères allyliques phosphonés cycliques, leur télomérisation, polymérisation et copolymérisation en solution par voie radicalaire mais aussi les premiers « essais feu» effectués. Les monomères allyliques phosphonés cycliques sont synthétisés par transestérification entre un glycol possédant une double liaison et un hydrogénophosphonate. La présence de diastéréoisomères nous a permis de faire une étude poussée en RMN pour comprendre la structure de ces composés. L'homopolymérisation radicalaire du dioxaphosphorinane hydrogéné faite en présence d'AIBN comme amorceur nous a permis d'obtenir des polymères avec 2 distributions chromatographiques composées d'oligomères et de polymères de haute masse moléculaire respectivement. Cette deuxième espèce présente une structure hyperbranchée avec des solubilités faibles qui nuisent aux futures applications. Des solutions alternatives ont été proposées comme la télomérisation de ce même monomère avec l'hydrogénophosphonate de diméthyle comme agent de transfert donnant une seule population d'oligomères. Le remplacement de l'hydrogène lié au phosphore par un groupement alkyle ou aryle simplifient le mécanisme de polymérisation pour former des chaînes macromoléculaires où les groupements phosphonés sont situés dans les chaînes latérales. La copolymérisation Accepteur/Donneur entre l'anhydride maléique et les allyl éthers phosphonés a été envisagée pour produire des copolymères alternés avec la possibilité d'introduire des groupements différents comme les acides carboxyliques, potentiellement intéressants pour la résistance au feu. Une dernière solution, utilisant la synergie des atomes d'azote et de phosphore, a été mise en oeuvre par la synthèse d'oligomères allyl amine phosphonés par polymérisation radicalaire en solution aqueuse. Un bilan de tous les polymères phosphonés a été réalisé dans le but de tester leurs performances en tant que retardateurs de flamme. Les caractérisations en analyse thermogravimétrique et en microcalorimètre ont montré une bonne thermostabilité des télomères comme des copolymères et une chaleur dégagée équivalente au produit de référence. Les essais feu sur textile au cône calorimètre montrent que des résultats encourageants sur les polymères synthétisés. / Since July 2008, a wide rnage of halogenated flame retardants was withdrawed from the market for environmental problems by the European Union. The phosphorous products turn out to be promising candidates. Within the framework of my thesis, the synthesis of allyl cyclic phosphonated monomers is described as well as their telomerization, polymerization and copolymerization in solution using a radical process). Their flame retardant behavior was also evaluated. Allyl cyclic phosphonated monomers are synthesized by transesterification between a glycol with a double bond and hydrogenophosphonate. An NMR study of the obtained diastereoisomers allowed us to fully understand the structure of these compounds. Radical homopolymerization of hydrogenated dioxaphosphorinane, in the presence of AIBN as initiator, allowed us to obtain polymers with two molar mass distributions: one for oligomers and one for polymers of higher molar mass. This second species is due to a hyperbranched structure showing poor solubility in common solvents, which damage the future applications. The telomerization of the same monomer was carried out using dimethyl hydrogenophosphonate as chain transfer agent leading only one population of oligomers. Furtehrmore, the replacement of the hydrogen linked to phosphorus by an alkyl or aryl group simplify the mechanism of polymerization since only linear oligomers are obtained. Acceptor-donor copolymerization of maleic anhydride and phosphonated allyl ethers, allowed producing alternated copolymers with the opportunity to introduce different reactive groups such as carboxylic acids. Then, oligomers were produced by radical polymerization of phosphonated allyl amine in order to potentially use the nitrogen-phosphorus synergy. An overview of all the phosphonated polymers previously synthesized, was done with the aim of testing their flame retardant performances. Thermogravimetric analysis showed a good thermal behavior of the telomers and the copolymers, similar heat release rate was observed by microcalorimeter compare to commercial product. High efficiency of these phosphorus-containing flame retardants polymers was finally evidenced by using the cone calorimeter on textile.

In the pursuit of lower cost intumescent flame retardant (IFR) systems, the compound expandable graphite (EG) was identified. This compound delivers high flame retardant performance but provides non-uniform thermal shielding when exposed to open flame from below due to negative gravitational effects. It was theorised that this may be remedied either through ion exchange of the interstratified ions with low glass transition ions or through use in binary systems with other compounds. Two classes of commercial EG were identified, namely a low and a high expansion onset temperature EG compound. Extensive characterisation of each EG compound was undertaken to assess its composition, expansion mechanisms and onset temperatures in order to identify compatible compounds for binary use. The susceptibility of each compound to ion exchange was also assessed. An industrial IFR ethylenediamine phosphate (EDAP) and a novel flame retardant were synthesised for assessment in binary use with EG. Coupled with the above study, this project developed two novel fire testing techniques as low cost alternatives to well-established fire testing methods such as cone calorimetry. The first technique involved an open flame fire testing method which allowed vertical or horizontal testing. Digital and infrared (IR) video recording during operation facilitated comparison of multiple performance indicators further strengthening this method. The second technique allowed assessment of the mass loss resistance of each compound during laser pyrolysis. Characterisation of the EG compounds allowed development of structural models to describe each compound and explain the mechanisms of their expansion and gaseous release. Exhaustive ion exchange testing did not deliver favourable results, necessitating the pursuit of compounds for binary use with EG. A novel IFR was synthesised by neutralising 3,5-diaminobenzoic acid hydrochloride salt with ammonium dihydrogen phosphate. This compound, which melts at 257 °C, decomposes concurrently to release carbon dioxide gas which promotes intumescent charring. The flame retardant performance of this compound and EDAP as primary flame retardants and in combination with expandable graphite was evaluated. As a proof of concept, the novel compound was tested as a primary flame retardant using cone calorimetry after which its utility in binary systems with low temperature expandable graphite was tested. Substantial decreases in peak heat release rate (pHRR) and flame out time were achieved for all binary systems. This success led to testing of a number of combinations of low and high expansion onset EG and the other IFRs to identify the highest performing combination, which proved to be the 10-10 EDAP-EG system. Combinations of EG and the novel compound also showed excellent results. The novel fire testing techniques proved effective in identifying high performance combinations and showed comparable trends to those measured in cone calorimetry, at a greatly reduced cost and material requirement. IR analysis of open flame fire testing indicated increases in the temperatures required for ignition and burn through of the substrate. Observations, corroborated by optical video, showed that cohesive and uniform thermal shielding was achieved in all binary systems tested. This study illustrates that systems of 10% EG combined with either 10% DABAP or 10% EDAP are both the most economical binary systems tested but are extremely high performance systems as well. Both of these systems delivered excellent results while being more economic than the widely used industrial system with a 25-30% EDAP loading. It is recommended that these compounds be considered for industrial use. Furthermore, the effective fire testing techniques developed in this study may be utilised in future fire testing to identify high performance compounds at a lower cost prior to further assessment through methods such as cone calorimetry. / Thesis (PhD)--University of Pretoria, 2017. / Chemical Engineering / PhD / Unrestricted

Flame retardant chemicals were used to make flammable fibres or fabrics flame retardant. Flame retardants protect the flammable material from fire by delaying or preventing the ignition process. The problem with flame retardants is unreliable durability when applied physically or bonded chemically on the surface of the fibre or fabric. This thesis project investigated the implementation of inherently flame retardant fibres as a shield form flame for flammable fibres. The most widely used flammable textiles fibres (cotton and polyester) were mixed with inherently flame retardant fibres (modacrylic and Lenzing FR) pairwise at fibre level for non-woven fabric and both fibre &amp; yarn level for knitted fabric. The vertical flame test, where the fabric hung vertically and burned from the bottom, was used to characterise their burning behaviour. With the vertical flame test, it was found that flame shielding ability of inherently flame retardant fibres towards flammable fibres improves with an increasing proportion of inherently flame retardant fibres in the fabric. Also, fabric structure influences the shielding properties of the flame retardant fibres. A comparison between fibre and yarn level mixing for knitted fabric yarn level mixing was found to have better flame shielding properties. Thesis work points out the issue with flame retardant chemical and presents an alternative approach for conventional flame retardant.

No description available.

The following project work studies trusses and roof structures and their performance during a fire in terms of rules and requirements that needs to be considered. Determination of how resistant truss or roof construction is still heavily dependent on the subjective experience and assessment of professional. It means that nowadays stages of this defining of fire resistance of roof/truss are still in need of clarification. The load combination for accidental load is compared to the ultimate limit state during the fire and it was showed that the loads were lower. The strength of timber during the fire was calculated by the two methods. Calculations by both methods revealed that timber used in construction can withstand fire by 0 minutes. However, fire resistance of the wooden materials can be improved by different techniques that were described in this study. The biggest improvement of fire resistance can be achieved with the help of covering - gypsum boards and rockwool, or even with wooden covering if lower protection is needed. As well, many fire-retardant treatments were developed that can improve wood performance during fire by slowing down the spread of fire, by limiting the building up of smoke and other volatiles. Instead of fire-retardant treatment fire retardant paints can be used too. This study showed stages of establishing fire requirements of wooden roof structures by two examples. In this study, two calculations were performed for two different house types, a family house, and an apartment building, to compare the difference between normal load dimensioning and fire load dimensioning. In the fire load dimensioning method, two different times were considered - R30 and R60 load capacity. When calculating the normal load dimensioning, it has been shown that an unprotected truss has no fire resistance, and that the truss has a fire resistance, with respect to bearing capacity, which corresponds to R0, which means that it must be protected for the required time. / Samhällsbyggnad / Husbyggnad / Konstruktion