No description available.

Modern buildings increasingly include the usage of innovative materials aimed at improving sustainability and reducing the carbon footprint of the built environment. Phase Change Materials (PCMs) are one such group of novel materials which reduce building energy consumption. These materials are typically flammable and contained within wall linings yet there has been no detailed assessment of their fire performance. Current standard fire test methods provide means to compare similar materials but do not deliver knowledge on how they would behave in the event of a real fire. Thus, the aim of this thesis is to develop a novel testing framework to assess the behaviour of these materials in realistic fire scenarios. For PCMs, a flammability study is conducted in the bench-scale cone calorimeter to evaluate the fire risk associated with these materials. Then, micro-scale Thermogravimetric Analysis (TGA) is used to identify the fundamental chemical reactions to be able to confidently interpret the flammability results. Finally, intermediate-scale standard fire tests are conducted to evaluate the applicability of the bench-scale results to realistic fire scenarios. These take the form of modified Lateral Ignition and Flame spread Test (LIFT) and Single Burning Item (SBI) tests to understand flame spread and compartment fires respectively. Finally, a simplified method to combine this knowledge for use in building design is proposed. This method allows the balancing of potential energy benefits with quantified fire performance to achieve the specified goals of the designer. Hemp-lime insulation is a material which has also becoming increasingly popular in the drive towards sustainability. The porous nature of the material means that smouldering combustions are the dominant reaction mode but there is currently no standardised test method for this type of behaviour. Thus, hemp-lime materials also represent an unquantified risk. The work in this thesis defines a simple, accessible and economically viable bench-scale method for quantifying the fire risk associated with rigid porous materials. This is applicable for both downward opposed flow and upward forward flow smoulder propagation conditions. The behaviour is then interpreted using micro-scale thermogravimetric analysis to understand the underlying pyrolysis and oxidation reactions. Designers can utilise this framework to quantify the smouldering risk associated with hemp-lime materials to enable their usage in the built environment. The holistic fire risk assessment performed in this thesis has quantified the behaviour of PCMs and hemp-lime insulation applicable to realistic fire scenarios. The simplified design method empowers designers to be able to realise innovative buildings through fundamental understanding of the fire behaviour of these materials. The outcomes of this thesis allow designers to mitigate the fire risk associated with these materials and achieve optimised engineering solutions. Furthermore, the novel fire testing frameworks provide the economically viable means to assess the fire performance of future PCMs and hemp-lime products which ensures lasting relevance of this research in the future.

"Thanks to significant worldwide research directed at understanding and predicting structural behavior at elevated temperatures, analytical methods are available to support a rational, performance-based approach to the structural design of buildings for fire conditions. To utilize these analytical methods effectively, structural engineers need guidance on reliable and appropriate approaches to dealing with a variety of factors, including the effects of fire protection measures, temperature-dependent thermal and structural properties, elastic and inelastic behavior of structural components and assemblies, and thermal and structural response of framing connections. To meet the objective of guiding the structural engineer in appropriate analytical methods and parameter values for performance-based structural fire protection, this thesis proposes a comprehensive way of thinking about the design and analysis of structures for fire conditions. This integration of structural engineering and fire protection engineering into a functional framework is defined herein as Fire-Robust Structural Engineering (FRSE). The FRSE process, which is presented as a series of flowcharts, is designed to guide the structural engineer in executing the functions involved in the design of fire-safe structures and to help identify informational needs critical to these tasks. Currently, mechanisms for identifying possible resources to fulfill fire-related informational needs are generally organized for the convenience of the fire research community. Identification of resources that provide appropriate information for fire-robust structural engineering, such as laboratory fire test results, parametric studies of analytical methods, and other sources of guidance, is often difficult because these resources are rarely organized and presented for the benefit of structural engineers. To begin to resolve this problem, this thesis has developed a prototype information management system (IMS) based on the framework of the FRSE process. The IMS addresses the critical challenge of organizing and presenting the available knowledge and data in a format that is consistent with the perspective and informational needs of the structural engineer. The prototype version of the IMS has been implemented using a Microsoft Excel® platform. In addition to guidance in utilizing specific analytical methods and choosing appropriate parameter values, the structural engineer also requires an understanding of the input requirements and accuracy of various analytical methods in order to make informed decisions regarding which methods are appropriate for use with different structural configurations. Therefore, this thesis includes a model study as an example of a resource that could aid the structural engineer in making such decisions. The model study compares various analytical methods (simplified spreadsheet applications and advanced finite element techniques) to published laboratory test data and discusses concerns that the structural engineer must keep in mind when using each method. Conclusions are drawn regarding the appropriateness of each analytical method to the analysis of a fully restrained, spray-protected steel beam. Given this type of information, the structural engineer can make decisions regarding the types of analytical methods and the level of analytical sophistication required to solve a given design problem."

No description available.

This study mainly addresses the problem of estimating the prior earthquake damage on the response of reinforced concrete structures to future earthquakes. The motivation has arisen from the heavy damages or collapses that occurred in many reinforced concrete structures following two major earthquakes that recently occurred in the Marmara Region, Turkey. The analysis tool employed for this purpose is the package named IDARC2D. Deterioration parameters of IDARC&#039 / s hysteretic model have been calibrated using a search method. In the calibration process experimental data of a total of twenty-two beam and column specimens, tested under constant and variable amplitude displacement histories, has been used. Fine-tuning of deterioration parameters is essential for more realistic predictions about inelastic behavior and structural damage. In order to provide more realistic damage prediction, three ranges of parameters are proposed. Some damage controlling structural parameters have been assessed via a large number of two-dimensional section analyses, inelastic time history and damage analyses of SDOF systems and seismic vulnerability analyses of reinforced concrete buildings. Inelastic time history and damage analyses of numerous SDOF systems have been carried out to determine whether the loading history has an effect on damage and dissipated hysteretic energy. Then this emphasis is directed to the analyses of MDOF systems. In the analyses of the SDOF systems, various forms of constant and variable amplitude inelastic displacement reversals and synthetic ground motions composed of one of the four earthquake records preceded or followed by its modified records acted as a prior or successive earthquake, have been used. The analyses of two five-story R/C buildings have been caried out using synthetic accelerograms comprised of base input provided by the two recorded ground motions. It is shown that both damage progression and cumulative hysteretic energy dissipated along a path seem to depend on the number and amplitude of cycles constituting the path. However, final damage and accumulated hysteretic energy dissipated along a loading path are independent of the ordering of the same number and amplitude cycles along the path. There is a nonlinear relationship between the earthquake excitation intensity and final damage attained in the end. Increase in the acceleration amplitude leads to exponential increase in damage. As the prior earthquake intensity increases the damage from the succeding main earthquake decreases. A definite ground motion acting as prior and successive earthquake causes substantially different amount of damage. Prior earthquake damage does not substantially affect the maximum drift response in future larger earthquakes. A MDOF frame type structure with aprior damage suffers less overall damage in an earthquake in comparison with the one without a prior damage.

Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-09-30T19:40:50Z No. of bitstreams: 1 DissGIS.pdf: 3988333 bytes, checksum: a681d0f291f122eb333cf27b8bd8845b (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T18:53:02Z (GMT) No. of bitstreams: 1 DissGIS.pdf: 3988333 bytes, checksum: a681d0f291f122eb333cf27b8bd8845b (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T18:53:12Z (GMT) No. of bitstreams: 1 DissGIS.pdf: 3988333 bytes, checksum: a681d0f291f122eb333cf27b8bd8845b (MD5) / Made available in DSpace on 2016-10-10T18:53:21Z (GMT). No. of bitstreams: 1 DissGIS.pdf: 3988333 bytes, checksum: a681d0f291f122eb333cf27b8bd8845b (MD5) Previous issue date: 2015-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The estimated housing deficit in Brazil was 5.6 million in 2008, in which 83.5% was in urban areas, wherein to meet such demand there is a need for industrialized construction. Prefabricated building systems with precast panels for residential buildings were largely applied in Europe after the Second World War and it has been applied recently in countries of Latin America and Asia. Although construction companies have been using building systems with precast panels for affordable housing in Brazil since the 80´s, the absence of a prescriptive code of practice for design of precast panels demands certification for each system, which needs to meet the performance requirements according to ABNT-NBR 15575:2013. In order to increase the application of prefabricated systems a new Brazilian Code of Practice for Precast Panels, based on international codes, has been concluded and it is now waiting for final approval. In order to achieve optimum performance, constructability and sustainability of the building project there is a need for integration between architectural and structural designs, as well the interaction between product and production, starting from product development based on the analysis of added value for each project until the rationalization of the processes. The level of prefabrication depends on the number and repetition of units. The aim of this research is to identify and define design guidelines based on performance for building systems with precast concrete panels for residential buildings. The literature revision was carried out starting from international references and codes until the study of the Brazilian codes of practice, including the new code for precast concrete panels. In addition, the research presents the main types of panels and typologies for residential buildings with potential to be applied in Brazil. Finally, an example of performance based design for precast concrete panels is presented with some discussions. This study demonstrate that architects and structural engineers can now design building systems with precast panels based on the new codes of practice and numeric simulations without the need of further tests for certification. / O déficit habitacional no Brasil era de 5,6 milhões em 2008, sendo 83,5% na área urbana, onde para atender esta demanda seria necessário o emprego da construção industrializada. Sistemas construtivos com painéis pré-moldados para residências foram amplamente aplicados na Europa após a Segunda Guerra Mundial, e também têm sido aplicados recentemente em países da América Latina e Ásia. Embora construtoras venham utilizando sistemas com painéis pré-moldados para habitações no Brasil desde a década de 80, a falta de normas prescritivas para projeto em painéis demanda certificações para cada sistema, que precisam atender aos requisitos de desempenho conforme a ABNT NBR 15575:2013. Com o objetivo de aumentar a aplicação de sistemas pré-fabricados, uma nova norma de prescrições brasileira, baseada em referências técnicas e normativas internacionais, foi concluída e aguarda sua aprovação final. Somente com integração entre os projetos das diferentes disciplinas é possível obter uma otimização de desempenho, construtibilidade e sustentabilidade da edificação, mas também deve haver a interação de projeto enquanto produto e produção, partindo do desenvolvimento do produto, com análise do valor agregado para cada solução de projeto até a racionalização do processo de produção, onde o nível de pré-fabricação depende do número e repetição das unidades a serem empreendidas. O objetivo desta pesquisa é identificar e sistematizar diretrizes de projeto com base no desempenho para sistemas construtivos em painéis pré-moldados de concreto, com aplicação em edifícios habitacionais. A revisão da literatura foi desenvolvida a partir das referências e normas internacionais, passando pelo estudo de normas brasileiras, incluindo o projeto de norma de painéis pré-moldados de concreto. Além disso, esta pesquisa apresenta os principais tipos de painéis e principais tipologias com potencial de aplicação para construções residenciais no Brasil. Finalmente, apresenta-se um exemplo de aplicação de avaliação de desempenho com a discussão de alguns resultados. Este estudo demonstra que arquitetos e engenheiros estruturais poderão, com a aprovação da nova normalização brasileira, desenvolver projetos com painéis pré-moldados em concreto com base em prescrições técnicas e simulações numéricas, sem a necessidade de se realizar novos ensaios para certificação para cada nova aplicação de sistemas construtivos pré-fabricados com painéis.

No description available.

[ES] El diseño de puentes, a diferencia de lo que ocurre con el diseño de edificios o con el diseño de túneles ha dejado de lado la consideración de la acción del fuego hasta la fecha. Este vacío normativo, combinado con la gran repercusión económica y social de colapsos de puentes en el pasado como consecuencia de incendios, ha motivado un rápido incremento del número de estudios relativos a la ingeniería frente al fuego en el ámbito de los puentes. Aunque la acción del fuego no resulta del todo desconocida en el ámbito de las estructuras, sí que existen una serie de singularidades que impiden la trasposición directa de recomendaciones o de modelos de fuego simplificados ya desarrollados en otros campos que ya incorporan la acción del fuego en el diseño. En este contexto, el trabajo que a continuación se expone parte de un incendio ocurrido en el estado de Alabama en 2002, cuyas consecuencias fueron la demolición de un puente mixto de 37 metros de vano central, para plantear y validar una metodología que aborda el problema de forma numérica mediante tres modelos acoplados secuencialmente: modelo de incendios, modelo térmico y modelo mecánico Realizada una validación a nivel general se descubre que, aunque la configuración geométrica final obtenida se ajustan bastante a la realidad, la definición del incendio ha supuesto un gran número de hipótesis. Es por ello que se decide, en una segunda parte, realizar una campaña experimental que permita registrar la potencia del fuego, las temperaturas del gas y del acero y las flechas en un puente construido ad-hoc en el campus de la Universitat Politècnica de València. Este puente experimental tenía un vano único de 6 m de luz y fue sometido a cargas de fuego de hasta 1.3 MW. Mediante el empleo de los registros realizados en la campaña experimental se ha validado el modelo de incendio, el modelo térmico y el modelo mecánico. Con todo ello se ha puesto en evidencia la importancia del viento en la acción del fuego, la magnitud de los gradientes térmicos espaciales y la urgencia de desarrollar procedimientos simplificados que permitan la incorporación del fuego como acción en el ámbito de los puentes Las validaciones específicas de cada modelo han permitido además llegar a una serie de conclusiones de gran interés para la realización de futuras campañas experimentales en puentes a mayor escala. / [CAT] El disseny de ponts, a diferència del que passa amb el disseny d'edificis o amb el disseny de túnels ha deixat de banda la consideració de l'acció del foc. Aquest buit normatiu, combinat amb la gran repercussió econòmica i social de col·lapses de ponts com a conseqüència d'incendis, ha motivat un ràpid increment del nombre d'estudis relatius a l'enginyeria del foc del foc en l'àmbit dels ponts. Encara que l'acció del foc no resulta del tot desconeguda en l'àmbit de les estructures, sí que hi ha una sèrie de singularitats que impedeixen la transposició directa de recomanacions o de models de foc simplificats ja desenvolupats en altres camps que ja incorporen l'acció del foc al disseny. En aquest context, el treball que a continuació s'exposa part d'un incendi ocorregut a l'estat d'Alabama en 2002 i que va provocar la demolició d'un pont mixt de 37 metres de va, per plantejar i validar una metodologia que aborda el problema de forma numèrica mitjançant tres models acoplats seqüencialment: model d'incendis, model tèrmic i model mecànic Realitzada una validació a nivell general es descobreix que, encara que la configuració geomètrica final obtinguda s'ajusta en gran mesura a la realitat, la definició de l'incendi ha suposat un gran nombre d'hipòtesis. És per això que es decideix, en una segona part, realitzar una campanya experimental que permeta registrar la potència del foc, les temperatures del gas i de l'acer i les fletxes en un pont construït ad hoc al campus de la Universitat Politècnica de València. Aquest pont experimental presenta un va únic de 6 m de llum i va ser sotmès a càrregues de foc de fins a 1.3 MW. Mitjançant l'ús dels registres realitzats a la campanya experimental s'ha validat el model d'incendi, el model tèrmic i el model mecànic. Amb tot això s'ha posat en evidència la importància del vent en l'acció del foc, la magnitud dels gradients tèrmics espacials i la urgència de desenvolupar procediments simplificats que permetin la incorporació del foc com a acció en l'àmbit dels ponts Les validacions específiques de cada model han permès a més arribar a una sèrie de conclusions de gran interès per a la realització de futures campanyes experimentals en ponts a major escala. / [EN] To date, the fire action has been left aside in the bridge design despite this action has been widely considered in other structures such as building and tunnels. This regulatory vacuum, combined with the great economic and social impact of bridge collapses in recent times as a result of fires, has led to a rapid increase in the number of studies related to fire engineering in the field of bridges. Although the action of fire is not entirely unknown in the field of structures, there are a number of singularities that prevent the direct transposition of recommendations or simplified fire models from such fields. In this context, the study started by using a real fire which occurred in the state of Alabama in 2002 and led to the demolition of the 37-meter main span of a composite concrete and steel bridge to introduce and validate a methodology that numerically addresses the problem by uncoupling the problem in three different models: fire model, thermal model and mechanical model. Once the validation was accomplished at a general level, it was discovered that, although the geometrical data were quite adjusted to reality, the definition of the fire had involved a large number of hypotheses. That is why carrying out an experimental campaign to record the power of the fire, the gas and steel temperatures and the vertical deflections of a bridge built ad-hoc on the campus of the Universitat Politècnica de València became a priority. This 6-meter single span experimental bridge was subjected to fire loads of up to 1.3 MW. Through the use of the information recorded during the experimental campaign, the fire model, the thermal model and the mechanical model were validated. Moreover, the importance of wind in the action of fire, the magnitude of spatial thermal gradients and the urgency of developing simplified procedures which allow the consideration of fire as an action in the field of bridges were also highlighted. Last but not least, the validation of the different models allowed the author to include useful guidelines in order to define future experimental campaigns with more powerful fires and longer span bridges. / Alós Moya, J. (2018). Análisis de la respuesta frente al fuego de puentes mixtos multijácena [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/116625 / TESIS