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This research evaluates the fracture behavior of concrete with reactive magnesium oxide (MgO). Replacing cement with MgO is an attractive option for the concrete industry, mainly due to sustainability benefits and reduction of shrinkage. Four different MgO’s from Australia, Canada, and Spain were used in the concrete mixes, as a partial substitute of cement, at 5%, 10%, and 20% (by weight). The fracture toughness (KI) intensity factor and the stress–strain softening parameters of the wedge split test were evaluated after 28 days. The experimental results showed that the replacement of cement with MgO reduced the fracture energy between 13% and 53%. Moreover, the fracture energy was found to be correlated with both compressive strength and modulus of elasticity. A well-defined relationship between these properties is important for an adequate prediction of the non-linear behavior of reinforced concrete structures made with partial replacement of cement with MgO.

A recent quest for more sustainable cement-based construction materials has triggered the pursuit of technically viable alternatives of cement, making reactive magnesium oxide (MgO) one of the least known top contenders to reduce this sector’s environmental impact since it participates in the cement’s hydration reactions and presents enhanced carbon capture ability during its life cycle. In this study, two different commercially available reactive MgO samples were evaluated as partial cement replacements (at 10%, 15%, and 20%, by weight) in the production of mortars. Thermogravimetric analysis (TGA), energy-dispersive X-ray (EDX) analysis, differential thermal analysis (DTA), and powder X-ray diffraction (XRD) analysis of cement, MgO samples, and resulting mortars were carried out. All specimens were evaluated in terms of their mechanical and durability-related performance (i.e., flexural and compressive strength, carbonation, water absorption by capillary action, and shrinkage). The main results suggest that, in spite of the decreased, albeit acceptable, performance with increasing incorporation of MgO as partial cement replacement, a significant decrease was observed in the shrinkage strain of cementitious materials.

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.

A statistical characterization of defects in 35 buildings and 98 wood floorings (softwood and hardwood floors, and laminated and engineered wood floors), their diagnostic methods and repair solutions is presented. An expert system for inspecting wood flooring, comprising the classification of defects, their most probable causes, diagnostic methods and repair techniques, was used. Results include age, affected area, severity and frequency of defects and their main causes, as well as appropriate diagnostic methods, preventive and curative repair solutions most prescribed and the most significant correlations. Scratches were detected in more than five sixths of the sample, highly associated with exterior mechanical actions, and with an inadequate finishing layer. Wearing of the finishing layer was detected in a quarter of the inspected floorings. Accordingly, the application of a suitable finishing layer and, alternatively, its replacement are the most prescribed repair techniques.

This paper presents an expert system to support the inspection and diagnosis of partition walls or wall coverings mounted using the Drywall (DW) construction method. This system includes a classification of anomalies in DW and their probable causes. This inspection system was used in a field work that included the observation of 121 DWs. This paper includes a statistical analysis of the anomalies observed during these inspections and their probable causes. The correlation between anomalies and causes in the sample is also thoroughly analyzed. Anomalies are also evaluated for area affected, size, repair urgency and aesthetic value of the affected area. The conclusions of the statistical analysis allowed the creation of an inventory of preventive measures to be implemented in the design, execution and use phases in order to lessen the magnitude or eradicate the occurrence of anomalies in DW. These measures could directly help improve the quality of construction.

The present article addresses tile joint defects in interior and exterior floors and walls. It begins with a classification of tile joint defects along with their likely causes, establishing a correlation matrix between the two sets of parameters. This is followed by the identification of the flaws found most frequently in this type of cladding, based on field data collected during 88 inspections of tile joint material. The statistical analysis of these data is shown in the form of charts representing the frequency of joint defects, their causes and the interrelationships between the two. The field work confirmed the high frequency of joint defects in all types of tiling. This conclusion underscores the need for proper joint design and maintenance planning (including periodic inspection and repair as appropriate) to guarantee the durability of this type of cladding.

Los modelos de predicción de la vida útil intentan extrapolar el comportamiento futuro de los elementos de construcción, anticipando el punto en el que se requiere la intervención. Cadenas de Markov se pueden usar para evaluar la condición futura de los elementos de construcción y se utilizan en este estudio para modelar la vida útil de revestimientos pétreos, a partir de las inspecciones visuales de edificios en servicio. La degradación de los revestimientos pétreos se califica en una escala discreta de cinco niveles, y se evalúa la probabilidad de transición de condiciones de degradación. Este estudio también permite comprender la influencia de las condiciones de exposición en la evolución de la degradación de los revestimientos.

La comunidad científica internacional ha dedicado mucha atención a la vasta área de conocimiento de la inspección, diagnóstico, mantenimiento y rehabilitación de edificios, que se puede utilizar en el desarrollo de sistemas de gestión de edificios integrados. En este artículo, se realiza un encuadramiento de los métodos de evaluación de patología en elementos no estructurales de los edificios, basado en los actuales, presentando algunos de los desafíos en esta área. También se presenta un modelo a implementar en sistemas integrados de gestión de un edificio, formando una línea conductora y una base consistente para un sistema que se ponga en su lugar.

RESUMEN Um dos principais problemas na reabilitação de estruturas de betão que estiveram sujeitas à acção de um fogo, é a determinação da espessura degradada do betão que necessita ser substituida, não havendo presentemente nenhuma técnica expedita para o realizar. Neste artigo apresenta-se um método de ensaio (Fire Behaviour Test - FBTEST), desenvolvido pelos autores, em que a espessura degradada de betão é quantificada recorrendo à medição das características de absorção de água e da tensão de rotura à tracção de discos obtidos a partir de carotes retiradas na estrutura danificada. Esta técnica tem vindo a ser aplicada com sucesso em peritagens de incêndios em estruturas de betão. Palabras Clave: Dano de fogo; concreto; estruturas; reabilitação; 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.

Objective: To translate, culturally adapt, and validate a Brazilian Portuguese version of the Yale-Brown Obsessive Compulsive Scale modified for Body Dysmorphic Disorder (BDD-YBOCS). Methods: Ninety-three patients of both sexes seeking rhinoplasty were consecutively selected at the Plastic Surgery Outpatient Clinic of the Universidade Federal de São Paulo, Brazil, between May 2012 and March 2013. The BDD-YBOCS was translated into Brazilian Portuguese. Thirty patients participated in the cultural adaptation of the scale. The final version was tested for reliability in 20 patients, and for construct validity in 43 patients (correlation of the BDD-YBOCS with the Body Dysmorphic Disorder Examination [BDDE]). Results: Total Cronbach’s alpha was 0.918. The BDD-YBOCS had excellent inter-rater (intra-class correlation coefficient [ICC] = 0.934; p < 0.001) and intra-rater reliability (ICC = 0.999; p < 0.001). Significant differences in BDD-YBOCS scores were found between patients with and without BDD symptoms (p < 0.001), and among patients with different levels of BDD severity (p < 0.001). A strong correlation (r = 0.781; p < 0.001) was observed between the BDDE and the BDD-YBOCS. The area under the receiver operating characteristic curve was 0.851, suggesting a very good accuracy for discriminating between presence and absence of BDD symptoms. Conclusion: The Brazilian Portuguese version of the BDD-YBOCS is a reliable instrument, showing face, content and construct validity.

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.

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.

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

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.

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.