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In a future scenario in which all the concrete is recycled concrete, it will be necessary to recycle the recycled concrete. However, it is known that the recycling of concrete implies a loss of properties. This paper shows an innovative technique, the computerized microtomograph, used to evaluate closed porosity, volume of limestone aggregate fraction and volume of mortar of the multi-recycled aggregate concrete, in order to answer the question: how many times it is possible to recycle concrete? First, the source concrete mix using limestone coarse and fine aggregates was characterized. This mix was crushed to obtain a recycled aggregate that was used to manufacture the 1st generation or current recycled aggregate concrete. After the characterization of this 1st generation concrete, and in the same way, a 2nd and a 3rd generation concrete were obtained and characterized, using recycled aggregates from the 1st and 2nd concrete generations respectively. The evaluation by computerized axial tomography allows to know how the successive recycled affect the properties of the concrete. The results show that it is possible to observe the distribution and quantify the aggregate, cement paste and closed porosity contents of the recycled aggregate concrete showing that 3rd generation recycled concrete shows almost twice as much mortar as 1st generation one and demonstrates that it is only possible to recycle the concrete a finite number of times.

The aim of this paper is to identify existing methods for economic valuation or monetisation of life cycle environmental impacts and to assess its applicability in the broad European context. Although environmental awareness is more and more important in several industrial sectors, including the construction sector, easy to understand data are still missing for professionals to assess and manage impacts related to the whole life cycle of a building. Life Cycle Assessment (LCA) is one of the most commonly accepted methodologies to calculate potential life cycle environmental impacts of a product or service. However, the results of such method, even when published in an Environmental Product Declaration, meant for business to business communication, are not always comparable or easily understandable by non-practitioners. Economic valuation or monetisation of LCA results is a weighting step that can make it easier for non-practitioners to use LCA results to support decision-making. From the several monetisation methods analysed, it is discussed the one that is most suitable for use when LCA results already exist. It is concluded that further work is needed to improve such weighting methods or develop a common one that can be representative at a broader geographical level (for instance, Europe-wide)., This work was supported by FCT - Fundação para a Ciência e Tecnologia [grant number PD/BD/127850/2016] under the Doctoral Program EcoCoRe - Eco-Construction and Rehabilitation. Support from CERIS and Instituto Superior Técnico is also acknowledged.

This paper presents a complete and updated literature review on the properties of self-compacting concrete with fine and coarse recycled aggregates. The subject of self-compacting concrete with recycled aggregates (RASCC) is greatly relevant to Society, since there is an increasing demand from the construction industry to adopt new processes to minimize its negative impacts on the environment. The use of recycled aggregates in concrete production presents a great environmental benefit through savings from the extraction of natural aggregates and the reduction of dumped material. The advantages associated to the use of both concrete with recycled aggregates and self-compacting concrete have boosted an increase in research and a consequent publication of literature in the last few years. Combining these two themes has allowed allying the environmental and economic advantages of each of the materials, leading to an innovative material of great interest to the construction industry in general. Even though RASCC is a relatively recent scientific area, studies on this material have demonstrated its viability, to produce both traditional and non-complex structural elements and highly complex and densely reinforced elements, which hinder the vibration procedures and may influence the final quality.

The construction sector is a major contributor to global environmental impacts. This is one of the reasons why there is a political trend towards a ?greener? sector. One indicator of this trend is the progressive application of life cycle thinking approaches and life cycle assessment of products, assemblies and buildings. The digitalization of construction projects, namely the use Building Information Modelling (BIM), can constitute a support to the automation of the application of Life Cycle Assessment (LCA) at the building?s design stage. However, besides the complexity of LCA model and results interpretation, BIM models usually lack LCA data that allow environmental impacts calculation. Currently, few publications explicitly relate the integration of LCA and BIM with the specificities of distinct development stages in the design and construction process or Levels of Development (LOD) of BIM objects. This paper summarizes the possible sources of LCA information to include in BIM models and discusses the complexity of LCA information needed for distinct BIM objects? LOD. A parametrization of environmental information is proposed, to be included in BIM objects, based on an evolutionary level of detail in LCA information for increasing LODs., This work was supported by FCT - Fundação para a Ciência e Tecnologia [grant number PD/BD/127850/2016] under the Doctoral Program EcoCoRe - Eco-Construction and Rehabilitation. Support from CERIS and Instituto Superior Técnico is also acknowledged., info:eu-repo/semantics/publishedVersion

This study intends to analyse the effects of the incorporation of recycled aggregates (RA) and densified silica fume (SF) on the durability of high performance concrete (HPC). Considering that the mortar adhered to the RA strongly influences the behaviour of the concrete made with it, the source of these aggregates was restricted to precast mixes with target compressive strengths of 75 MPa and subjected to a primary plus a secondary crushing process. With regard to SF, a certified commercial product was used, which was incorporated in the concrete as an additional material to cement. The experimental campaign included the production of 12 types of concrete, which were evaluated by means of water absorption by immersion, water absorption by capillarity, resistance to carbonation, resistance to chloride penetration and permeability to oxygen tests. The results show that it is possible to produce HPC with significant quantities of fine and coarse recycled aggregates (FRA and CRA) as replacement of traditional fine and coarse natural aggregates (FNA and CNA). Ultimately, considering the properties analysed, it seems possible to produce HPC without incorporating natural aggregates (NA). The incorporation of densified silica fume contributed to an increase of concrete's performance through the use of a mixing process developed by the authors that minimized the previously endured dispersion difficulties associated with this product.

A stochastic Petri-net formalism is proposed to predict the degradation of ceramic claddings over time in order to understand how different environmental exposure conditions contribute to the overall degradation of these claddings. For that purpose, the degradation condition of 195 ceramic claddings located in Lisbon, Portugal, is evaluated through in situ visual inspections. In the first part of the study, a stochastic deterioration Petri-net model is proposed for the entire sample. In the second part, the original sample is divided according to the environmental exposure conditions, evaluating the influence of these conditions on the deterioration process of ceramic claddings. Four main degradation agents are analyzed: exposure to moisture; distance from the sea; orientation; and wind–rain action. The results reveal that Petri nets can accurately describe the deterioration process of ceramic claddings, providing relevant information regarding the performance of these claddings through their life cycle and according to the environmental exposure conditions to which they are subject. These results are extremely relevant for different practitioners: the approach allows the adoption of more sustainable and durable solutions at the design stage, as well as improving the durability of the ceramic claddings by performing optimized maintenance plans and strategies.

The construction field has contributed to environmental degradation, producing a high amount of construction and demolition waste (C&D waste) and consuming large volumes of natural resources. In this context, recycled concrete (RC) has been recognised as a means to preserve natural resources and reduce space for waste storage. During the last decades, many researchers have developed works studying different recycled concrete properties. This review focuses on structural RC made with coarse recycled aggregate from concrete waste. The main objective is to provide a state of the art report on RC’s properties and an analysis on how to predict them taking into account relevant research works. Moreover, the study tries to collect and update RC findings, proposing equations to define RC’s performance, in terms of mechanical strength, modulus of elasticity, stress-strain, creep and shrinkage. El campo de la construcción ha contribuido a la degradación del medio ambiente, produciendo gran cantidad de residuos de construcción y demolición y consumiendo grandes volúmenes de recursos naturales. En este contexto, el hormigón reciclado se ha presentado como una opción para preservar los recursos naturales y reducir el espacio destinado a vertedero. Así, durante las últimas décadas, muchos investigadores han desarrollado trabajos para estudiar las propiedades del hormigón reciclado. Este artículo se centra en el hormigón estructural fabricado con árido reciclado grueso procedente de residuos de hormigón. El principal objetivo es desarrollar un estado del arte que recoja las principales propiedades del hormigón reciclado y un análisis de cómo calcularlas teniendo en cuenta un gran número de trabajos relevantes en este ámbito. Adicionalmente, el estudio recopila y actualiza el conocimiento sobre estos hormigones, proponiendo ecuaciones que permitan definir sus resistencias mecánicas, módulo de elasticidad, tensión-deformación, fluencia y retracción.

In this study, a methodology to model and predict the life-cycle performance of building facades based on Stochastic Petri Nets is proposed. The proposed model evaluates the performance of rendered facades over time, evaluating the uncertainty of the future performance of these coatings. The performance of rendered facades is evaluated based on a discrete qualitative scale composed of five condition levels, established according to the physical and visual degradation of these elements. In this study, the deterioration is modelled considering that the transition times between these condition states can be modelled as a random variable with different distributions. For that purpose, a Stochastic Petri Nets model is used, as a formal framework to describe this problem. The model's validation is based on probabilistic indicators of performance, computed using Monte-Carlo simulation and the probability distribution parameters leading to better fit are defined as those maximizing the likelihood, computed using Genetic Algorithm. In this study, a sample of 99 rendered facades, located in Portugal, is analysed, and the degradation condition of each case study is evaluated through in-situ visual inspections. The model proposed allows evaluating: i) the transition rate between degradation conditions; ii) the probability of belonging to a given degradation condition over time; and iii) the mean time of permanence in each degradation condition. The use of Petri Nets shows to be more accurate than a more traditional approach based on Markov Chains, but also allows developing future research to consider different environmental conditions, maintenance actions or inspections, amongst other aspects of life-cycle analysis of existing assets.

The shrinkage and durability properties of a total of 34 concrete mixes with recycled aggregates produced from different untreated construction and demolition waste (CDW) were tested. The effect of a polycarboxylic superplasticizer on the enhancement of these properties is presented, discussed, and compared with the findings of studies on concrete whose recycled aggregates are sourced from concrete. All properties were significantly affected by recycled aggregate incorporation and this effect was strongly dependent on the properties of the recycled aggregates of each specific source. The superplasticizer was less efficient in mixes with CDW than when the recycled aggregates were produced from concrete, the most common source of recycled aggregates in experimental works, despite untreated CDW being more practical and desirable from an industrial and environmental perspective.

This paper presents a novel technique used to analyse the volume of adhered mortar to the recycled aggregate. A computerized microtomograph (?CT) device was used to evaluate the volume of the aggregate, the volume of natural aggregate and the volume of adhered mortar. To this end, a natural aggregate has been characterized, using the ?CT, with which a source concrete has been produced. Subsequently, the source concrete has been crushed to obtain a first cycle recycled aggregate. After the characterization of the first-generation of recycled aggregate, a new source concrete has been made with it to be subsequently crushed again obtaining a second-generation recycled aggregates. In the same way a third-generation recycled aggregate has been obtained and has been equally characterized. The results show that the compaction capacity of the aggregate is reduced after successive recycling. It has been possible to quantify how much the closed porosity of the recycled aggregate decreases with the number of times it is recycled. The loss of natural aggregate and increase of the volume of adhered mortar have also been evaluated using this technique. The Erasmus+Program, founded by the Staff Mobility for Teaching Program of the European Council 2016/217, between Instituto Superior Técnico - University of Lisbon and the LADICIM - University of Cantabria. CERIS and the Foundation for Science and Technology (FCT) for funding this research.

This study identifies the main anomalies that may occur in historical buildings, analyzing their related causes, and estimating the influence of pathological situations on the buildings’ functionality. This information is essential to support qualified, conscientious, and sustainable rehabilitation interventions on sets of heritage buildings with homogeneous constructive characteristics. A fuzzy expert system was used to estimate the serviceability of buildings, performed based on historical records, over a long period of time, evaluating the influence of the pathological situations to establish the rehabilitation actions. The methodology includes 17 variables, (vulnerabilities and external risks damages), which determine a functionality index of the constructions analyzed. The application of historical data allows knowing the past behavior and performance of the buildings. These data can provide useful information for the definition of preventive maintenance plans, considering financial, social, and environmental requirements and their more frequent anomalies. A total of 390 records in a sample of 20 parish churches located in southwestern Spain were gathered. This study discussed the effects of the most common anomalies observed in these buildings, concluding that controlling moisture and timber-related anomalies is crucial to ensure the building’s serviceability over time. © 2017 Taylor & Francis.

Self-compacting concrete’s (SCC’s) particular need for self-compacting, i.e. to achieve a high passing and filling ability, deformability capacities and a high resistance to segregation, necessarily requires the reduction of the volume of coarse aggregate and the increase of the volume of ultrafine materials and admixtures (mainly superplasticisers). The increase in the volume of ultrafine materials mentioned, achieved exclusively at the cost of the cement, would have, as main effects, the significant increase of the overall cost of SCC, of its hydration heat and potential effects on properties such as shrinkage and cracking. Consequently, significant amounts of mineral additions are usually incorporated, in replacement of part of the cement to improve the workability properties, reduce the production of hydration heat and reduce the overall cost. Mainly because it needs to incorporate significant quantities of ultrafine materials (cement and mineral additions), SCC has great potential for the use of thes...

Capital social é discutido no âmbito do Consórcio Brasileiro de Pesquisa e Desenvolvimento de Café. O objetivo é investigar a viabilidade de utilizar o capital social como instrumento para explicar o gradiente de recursos do consórcio de que os pesquisadores conseguem se apropriar para seus projetos de pesquisa. Foi desenvolvida e aplicada uma métrica de capital social para testar a existência de correlação entre volume de recursos captado e volume de capital social. A análise sociométrica de escolhas preferenciais dos pesquisadores e a quantificação da participação desses cientistas em projetos do consórcio permitiram o cômputo de uma grandeza - capital social - que poderia vir a explicar metade da variação da verba obtida pelos cientistas responsáveis por projetos de pesquisa na rede.

The aim of this paper is to evaluate the influence of the crushing process used to obtain recycled concrete aggregates on the performance of concrete made with those aggregates. Two crushing methods were considered: primary crushing, using a jaw crusher, and primary plus secondary crushing (PSC), using a jaw crusher followed by a hammer mill. Besides natural aggregates (NA), these two processes were also used to crush three types of concrete made in laboratory (L20, L45 e L65) and three more others from the precast industry (P20, P45 e P65). The coarse natural aggregates were totally replaced by coarse recycled concrete aggregates. The recycled aggregates concrete mixes were compared with reference concrete mixes made using only NA, and the following properties related to the mechanical and durability performance were tested: compressive strength; splitting tensile strength; modulus of elasticity; carbonation resistance; chloride penetration resistance; water absorption by capillarity; water absorption by immersion; and shrinkage. The results show that the PSC process leads to better performances, especially in the durability properties.

Cement, as well as the remaining constituents of self-compacting mortars, must be carefully selected, in order to obtain an adequate composition with a granular mix as compact as possible and a good performance in the fresh state (self-compacting effect) and the hardened state (mechanical and durability-related behavior). Therefore in this work the possibility of incorporating nano particles in self-compacting mortars was studied. Nano materials are very reactive due mostly to their high specific surface and show a great potential to improve the properties of these mortars, both in mechanical and durability terms. In this work two nano materials were used, nano silica (nano SiO 2 ) in colloidal state and nano titanium (nano TiO 2 ) in amorphous state, in two types of self-compacting mortars (ratio binder:sand of 1:1 and 1:2). The self-compacting mortar mixes have the same water/cement ratio and 30% of replacement of cement with fly ashes. The influence of nano materials nano-SiO 2 and nano-TiO 2 on the fresh and hardened state properties of these self-compacting mortars was studied. The results show that the use of nano materials in repair and rehabilitation mortars has significant potential but still needs to be optimized.

This paper evaluates the influence of two superplasticizers (SP) on the rheological behaviour of concrete made with fine recycled concrete aggregates (FRCA). Three families of concrete were tested: family C0 made without SP, family C1 made with a regular superplasticizer and family C2 made with a high-performance superplasticizer. Five replacement ratios of natural sand by FRCA were tested: 0%, 10%, 30%, 50% and 100%. The coarse aggregates were natural gravels. Three criteria were established to design the concrete mixes’ composition: keep the same particle size distribution curves, adjust the water/cement ratio to obtain a similar slump and no pre-saturation of the FRCA. All mixes had the same cement and SP content. The results show that the incorporation of FRCA significantly increased the shrinkage and creep deformation. The FRCA’s effect was influenced by the curing age. The reference concrete made with natural sand stabilizes the creep deformation faster than the mixes made with FRCA. The incorporation of superplasticizer increased the shrinkage at early ages and decreased the shrinkage at 91 days of age. The regular superplasticizer did not improve the creep deformation while the high-performance superplasticizer highly improved this property. The incorporation of FRCA jeopardized the SP’s effectiveness. This study demonstrated that to use FRCA and superplasticizer for concrete production it is necessary to take into account the different rheological behaviour of these mixes.

This paper assesses the physical, chemical and mineralogical characteristics of fine recycled aggregates obtained from crushed concrete waste, comparing them with two types of natural fine aggregates from different origins. A commercial concrete was jaw crushed, and the effect of different aperture sizes on the particle size distribution of the resulting aggregates was evaluated. The density and water absorption of the recycled aggregates was determined and a model for predicting water absorption over time is proposed. Both natural and recycled aggregates were characterized regarding bulk density and fines content. Recycled aggregates were additionally characterized by XRD, SEM/EDS and DTA/TG of individual size fractions. The results show that natural and recycled fine aggregates have very different characteristics. This should be considered in potential applications, both in terms of the limits for replacing amounts and of the rules and design criteria of the manufactured products.

This paper describes a simple and rapid methodology for determining the content of adulterants in diesel by the integration of fluorescence spectra. The procedure consists of constructing analytical curves using the concentrations of each adulterant in diesel and the relative change in the fluorescence area of each blend with respect to the fluorescence area of the diesel. The results indicated that the proposed method can be used to determine adulterants such as non-transesterified residual cooking oil, kerosene, and turpentine in diesel. The detection limits were 3, 4 and 5% for non-transesterified residual cooking oil, kerosene and turpentine in diesel, respectively. The method was also successfully used to determine the non-transesterified residual cooking oil content in B5 biodiesel-diesel blend (5% biodiesel) in the range of 0-70%, with a limit of detection of 4%.

The international scientific community has paid great attention to the wide field of inspection, diagnosis, maintenance and rehabilitation of construction, which can be used in the development of integrated buildings management systems. This paper browses the methods of evaluation of the pathological situation of non-structural building elements, based on existing ones and presenting also some of the challenges in this field. A model to be implemented in integrated buildings management systems is also proposed, which is a consistent guideline and working basis for such a system to become a reality. Keywords: building pathology; expert knowledge-based system; assessment method; building management. Sistemas de gestao tecnica integrada de edificios: inspeccao e reparacao de elementos nao estruturais RESUMO A comunidade cientifica internacional tem dedicado a maior atencao ao vasto campo do conhecimento da inspeccao, diagnostico, manutencao e reabilitacao das construcoes, o qual pode ser utilizado no desenvolvimento de sistemas de gestao integrada de edificios. Neste artigo, e feito um enquadramento aos metodos de avaliacao da patologia em elementos nao-estruturais de edificios, com base nos actualmente existentes, apresentando-se alguns dos desafios neste dominio. E tambem apresentado um modelo a implementar em sistemas de gestao integrada de um edificio, constituindo uma linha condutora e uma base de trabalho consistente para que um sistema deste tipo seja posto em pratica. Palavras-chave: patologia da construcao; sistema pericial baseado no desempenho; metodo de avaliacao; gestao de edificios. Sistemas de gestion tecnica integrada de edificios: inspeccion y reparacion de elementos no estructurales RESUMEN La comunidad cientifica internacional ha dedicado mucha atencion a la vasta area de conocimiento de la inspeccion, diagnostico, mantenimiento y rehabilitacion de edificios, que se puede utilizar en el desarrollo de sistemas de gestion de edificios integrados. En este articulo, se realiza un encuadramiento de los metodos de evaluacion de patologia en elementos no estructurales de los edificios, basado en los actuales, presentando algunos de los desafios en esta area. Tambien se presenta un modelo a implementar en sistemas integrados de gestion de un edificio, formando una linea conductora y una base consistente para un sistema que se ponga en su lugar. Palabras clave: patologia de la construccion; sistema experto basado en el desempeno; metodo de evaluacion; gestion de edificios.

OBJETIVO: Avaliar a mortalidade dos recém-nascidos de muito baixo peso em uma UTI neonatal conforme as variações do escore CRIB (Clinical Risk Index for Babies), do peso de nascimento e da idade gestacional em determinado período. MÉTODOS: O escore CRIB foi aplicado seqüencial e prospectivamente em todos os recém-nascidos com peso de nascimento 10 (79,4%). A curva ROC (Receiver Operator Characteristic) para os valores de CRIB, peso de nascimento e idade gestacional gerou áreas sob a curva de 0,88, 0,76 e 0,81, respectivamente. Na análise bivariada, o CRIB, peso e idade gestacional mostraram-se preditores de mortalidade, sendo o escore CRIB>4 o de melhor resultado com sensibilidade de 75,8%, especificidade de 86,7%, valor preditivo positivo de 63,3% e valor preditivo negativo de 92,2%. CONCLUSÕES: Os recém-nascidos com peso de nascimento 10 tiveram maiores taxas de mortalidade, sendo o escore CRIB>4 o que representou melhor poder preditivo quando comparado com peso ao nascer e idade gestacional.OBJECTIVE: To evaluate the mortality rate of very low birth weight babies born at a Neonatal Intensive Care Unit (NICU) during a specified period of time according to variations in CRIB (Clinical Risk Index for Babies) score, birth weight and gestational age. METHODS: From January 1997 to December 2000, the CRIB score was prospectively applied to all newborn infants admitted to the NICU of an university hospital of Londrina, Brazil, with birthweight under 1,500 g and/or gestational age of less than 31 weeks. The exclusion criteria were: death before 12 hours of life, presence of lethal congenital malformations and newborns who had been referred from other hospital. RESULTS: Two hundred and eighty-four infants met the inclusion criteria. Mean birth weight was 1,148±248 g (median =1,180), mean gestational age was 30.2±2.4 weeks (median =30.0) and mean CRIB score was 3.8±4.4 (median =2.0). The neonatal mortality rate was 23.2%, varying according to mean birthweight 10 (79.4%). Receiver Operating Characteristic (ROC) curves were composed for CRIB score, birth weight and gestational age to assess the ability of each to predict hospital mortality and the areas under the curve were respectively 0.88, 0.76 and 0.81. Sensitivity, specificity and predictive values were evaluated and all variables were considered predictors of mortality (p

Due to their prominent properties (mechanical, stiffness, strength, thermal stability), ceramic composite materials (CMC) have been widely applied in automotive, industrial and aerospace engineering, as well as in biomedical and electronic devices. Because monolithic ceramics exhibit brittle behaviour and low electrical conductivity, CMCs have been greatly improved in the last decade. CMCs are produced from ceramic fibres embedded in a ceramic matrix, for which several ceramic materials (oxide or non-oxide) are used for the fibres and the matrix. Due to the large diversity of available fibres, the properties of CMCs can be adapted to achieve structural targets. They are especially valuable for structural components with demanding mechanical and thermal requirements. However, with the advent of nanoparticles in this century, the research interests in CMCs are now changing from classical reinforcement (e.g., microscale fibres) to new types of reinforcement at nanoscale. This review paper presents the current state of knowledge on processing and mechanical properties of a new generation of CMCs: Ceramics Nanocomposites (CNCs).

This paper intends to evaluate the capacity of producing concrete with a pre-established performance (in terms of mechanical strength) incorporating recycled concrete aggregates (RCA) from different sources. To this purpose, rejected products from the precasting industry and concrete produced in laboratory were used. The appraisal of the self-replication capacity was made for three strength ranges: 15–25 MPa, 35–45 MPa and 65–75 MPa. The mixes produced tried to replicate the strength of the source concrete (SC) of the RA. Only total (100%) replacement of coarse natural aggregates (CNA) by coarse recycled concrete aggregates (CRCA) was tested. The results show that, both in mechanical and durability terms, there were no significant differences between aggregates from controlled sources and those from precast rejects for the highest levels of the target strength. Furthermore, the performance losses resulting from the RA’s incorporation are substantially reduced when used medium or high strength SC’s.

In this study, an empirical method proposed by Caselles et al. (1992a) is utilized to determine the potential evapotranspiration (ETP) on a regional scale. This method uses the global solar radiation data retrieved by the global radiation model GL1.0, which in turn utilizes data from the visible channel of the GOES-8 satellite. This method is applied to the northeast region of Brazil, using daily and monthly climatological data as the ground truth information to estimate the ETP and the estimated daily ETP data for September, 1997. The methodology involved three steps: 1) to perform a spatial regionalization of the ETP using the method of Ward, which is available in the Statistical Package for the Social Sciences (SPSS); 2) to obtain the correlation between the ETP as estimated by the methods of Jensen & Haise (1963) - MJH, Caselles (1992a) - MCA, and the Penman's combined method (1948) - MCP; 3) to test the sensibility of the empirical formulations proposed and to assess the estimates using the satellite-based global solar radiation provided by the GL1.0 model. The spatial regionalization shows two distinct regions in the Northeastern Brazil. The MCA yielded better results than the MJH. The ETP estimates using satellite data were satisfactory, showing a maximum error of 20% when compared with the ground truth data.Neste trabalho foi utilizado o método empírico proposto por Caselles et al. (1992a) para determinar a evapotranspiração potencial (ETP) em escala regional. O método utiliza dados de radiação solar global obtidos a partir de um modelo de estimativa da radiação solar global (GL 1.0), que utiliza imagens do canal visível do satélite GOES-8. O método é aplicado no Nordeste do Brasil, utilizando como verdade terrestre dados climatológicos diários e mensais para estimar ETP e dados diários estimados de ETP para setembro de 1997. A metodologia contempla três etapas: 1) regionalização espacial da ETP obtida pelo método de WARD, disponível no software SPSS (Statistical Package for the Social Sciences); 2) correlação entre os valores de ETP estimados pelo método de Jensen & Haise (1963) MJH, Caselles et al. (1992a) MCA e pelo método combinado de Penman (1948) MCP, respectivamente; e, 3) teste de sensibilidade das formulações empíricas utilizadas e validação dos resultados. A regionalização espacial mostrou duas regiões distintas no Nordeste do Brasil. O MCA apresentou melhores resultados do que o MJH e a ETP estimada, usando dados de satélite, apresentou um erro máximo de 20%, quando comparada com a verdade terrestre.

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RESUMEN Um dos principais problemas na reabilitacao de estruturas de betao que estiveram sujeitas a accao de um fogo, e a determinacao da espessura degradada do betao que necessita ser substituida, nao havendo presentemente nenhuma tecnica expedita para o realizar. Neste artigo apresenta-se um metodo de ensaio (Fire Behaviour Test - FBTEST), desenvolvido pelos autores, em que a espessura degradada de betao e quantificada recorrendo a medicao das caracteristicas de absorcao de agua e da tensao de rotura a traccao de discos obtidos a partir de carotes retiradas na estrutura danificada. Esta tecnica tem vindo a ser aplicada com sucesso em peritagens de incendios em estruturas de betao. Palabras Clave: Dano de fogo; concreto; estruturas; reabilitacao; teste. ABSTRACT One of the major problems in the rehabilitation of concrete structures affected by fire is the quantification of the deteriorated layer of concrete that needs to be replaced. Presently there is no practical test to evaluate that deteriorated layer. In this paper a test method (Fire Behaviour Test – FBTEST) developed by the authors is presented allowing that evaluation by measuring the evolution, along the depth, of water absorption and tensile stress in discs obtained from disks from cores of the affected structure. This technique has been applied, with success, in several fire accidents in concrete structures. Keywords: Fire damage; concrete; structures; rehabilitation; test.

It is considered that using crushed recycled concrete as aggregate for concrete production is a viable alternative to dumping and would help to conserve abiotic resources. This use has fundamentally been based on the coarse fraction because the fine fraction is likely to degrade the performance of the resulting concrete. This paper presents results from a research work undertaken at Instituto Superior Tecnico (IST), Lisbon, Portugal, in which the effects of incorporating two types of superplasticizer on the mechanical performance of concrete containing fine recycled aggregate were evaluated. The purpose was to see if the addition of superplasticizer would offset the detrimental effects associated with the use of fine recycled concrete aggregate. The experimental programme is described and the results of tests for splitting tensile strength, modulus of elasticity and abrasion resistance are presented. The relative performance of concrete made with recycled aggregate was found to decrease. However, the same concrete with admixtures in general exhibited a better mechanical performance than the reference mixes without admixtures or with a less active superplasticizer. Therefore, it is argued that the mechanical performance of concrete made with fine recycled concrete aggregates can be as good as that of conventional concrete, if superplasticizers are used to reduce the water–cement ratio of the former concrete.

The reuse of structural concrete elements to produce new concrete aggregates is accepted as an alternative to dumping them and is favourable to the sustainability of natural reserves. Even though the construction sector is familiar with the use of coarse recycled concrete aggregates, the recycled concrete fines are classified as less noble resources. This research sets out to limit the disadvantages associated with the performance of concrete containing fine recycled concrete aggregates through the use of superplasticisers. Two types of latest generation superplasticisers were used that differ in terms of water reduction capacity and robustness, and the workability, density and compressive strength of each of the compositions analysed were then compared: a reference concrete, with no plasticisers, and concrete mixes with the superplasticisers. For each concrete family mixes with 0%, 10%, 30%, 50% and 100% replacement ratios of fine natural aggregates (FNA) by fine recycled concrete aggregates (FRA) were analysed. Concrete with incorporation of recycled aggregates was found to have poorer relative performance. The mechanical performance of concrete with recycled aggregates and superplasticisers was generally superior to that of the reference concrete with no admixtures and of conventional concrete with lower performance superplasticisers.

Following an experimental campaign involving APP and SBS-modified bituminous membranes and TPO polyolefin membranes (to be used in mechanically fastened single-layer flat roof waterproofing systems), with two different joint execution procedures (welding with an open gas torch and with hot air) and varying lap joint width, subjected to standard shear and peel resistance tests, this paper presents the results of the tests on the SBS-modified bituminous membranes with the purpose of evaluating the consequences of (water and heat) weathering on their mechanical performance.

Submitted by António Santos Silva (ssilva@lnec.pt) on 2009-09-25T15:15:35Z No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Approved for entry into archive by mpnunes@lnec.pt(mpnunes@lnec.pt) on 2009-10-08T11:27:40Z (GMT) No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Made available in DSpace on 2009-10-08T11:27:41Z (GMT). No. of bitstreams: 1 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Made available in DSpace on 2010-04-27T07:26:34Z (GMT). No. of bitstreams: 2 license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Made available in DSpace on 2014-10-20T16:32:22Z (GMT). No. of bitstreams: 2 T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) Previous issue date: 2009-04 Made available in DSpace on 2017-04-12T15:03:52Z (GMT). No. of bitstreams: 2 license.txt: 1838 bytes, checksum: 9772d38e2cd23107e941a23ec84a6a35 (MD5) T.Freire-A237 full paper-Materiais 2009.pdf: 7249 bytes, checksum: 545a066a20e07fa74b17f957a2d45b0d (MD5) Previous issue date: 2009-04 Teresa Freire’s PhD research study is being supported by the scholarship SFRH/BD/40128/2007 from Fundação para a Ciência e Tecnologia (FCT). The authors would also like to thank the technicians Susana Couto and Paula Menezes from Materials Department and Dora Santos, from the Buildings Department of LNEC, for their support on the execution of the experimental work. 3 4 6p DM/NMM 2009 5 a 8 de Abril