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• AAS showed higher carbonation than Portland cement. • The carbonation of AAS was related to intense shrinkage and absence of Ca(OH) 2. • GBFS from charcoal was unable to reduce the susceptibility of AAS to carbonation. In Brazil, 20% of annual steel production is from charcoal, with growth prospects due to the increase in the use of charcoal as a substitute for coke. The slags from coal blast furnaces (coke) have a large percentage of CaO to remove the present sulfur while those produced in charcoal blast furnaces have a low CaO-SiO 2 ratio. Alkali-activated slag (AAS) is a type of cement obtained mostly from GBFS, which has good mechanical properties for engineering and low environmental impact in its production process. This process is based on the activation of the slag by an alkaline solution, such as hydroxides or silicates. However, because the product of hydration consists essentially of CASH, carbonation in AAS has been investigated. Also, studies dedicated to AAS from charcoal (low CaO/SiO 2) are not common. Therefore, the goal of this paper was to study the behavior of GBFS-based AAS from charcoal under carbonated conditions by accelerated tests and compare it with that of Portland cement. The results showed that AAS presented higher carbonation depths (127.1 mm) than Portland cement (PC) (77.1 mm) and a sharp decrease in compressive strength from 37 to 28 MPa, which was related to intense shrinkage, decalcification of CSH and formation of vaterite. Although the slag from charcoal has more Al 2 O 3 (13%) and MgO (6%), it was unable to form aluminosilicate or hydrotalcite, which could reduce the susceptibility of AAS carbonation. [ABSTRACT FROM AUTHOR]

• WTS waste used as raw material to the production of new SCM. • WTS waste processed by flash calcination and electrical muffle furnace. • Different temperature and residence time investigated. • Characterization performed to verify the potential pozzolanic activity. • Calcined WTS shows great potential to the production of a new SCM. This paper investigates the potential of using calcined water treatment sludge to the development of supplementary cementitious material. Sludge samples have been collected in the drying beds of a water treatment plant located in Southern Brazil and calcined in the laboratory. Chemical and mineralogical characterization has been performed through energy dispersive X-ray spectrometry, thermogravimetric analysis, and X-ray diffraction with crystalline phases quantified by Rietveld refinement. Morphological analysis has been supported by scanning electron microscope images. Physical characterization has been carried out through specific surface area, particle size distribution, and pozzolanic activity performance with Portland cement. Results have shown that the water treatment sludge is a non-hazardous and non-inert waste without environmental restrictions for use in construction. Considering technical, environmental and economic aspects related to energy consumption, sludge samples calcined at 600 °C for 1 h present the most promising results regarding the production of supplementary cementitious material equivalent to a normal pozzolan, while highly active pozzolan requires 750 °C for 1 h. Calcined water treatment sludge showed great technical and environmental potential to be used as an alternative source of supplementary cementitious material in the near future. [ABSTRACT FROM AUTHOR]

Highlights • Comparative analysis between two Brazilian sub-ballast specifications derived from American specifications. • Analysis of the requirements for sub-ballast materials. • Qualitative tests of granular materials and their results. • Analysis of the results obtained in current requirements from non-American sources. Abstract In the period 1975–1985 several new railway infrastructures were built in Brazil. After this period the construction of new railways stopped. With the new railway concessions in 1996, minor maintenance work was undertaken on the old railway infrastructures and only in the last six years have new railway infrastructures begun to be constructed. In São Paulo, between 1978 and 1985, some old railways infrastructures were also rebuilt using sub-ballast or platform with granular soils in the track layers. This paper presents a comparative analysis between two sub-ballast specifications, one used in the 1975–1985 period and another used nowadays for new railway constructions in Brazil. The main sub-ballast functions were identified, including the bearing capacity and the hydraulic conductivity. To assess the sub-ballast in terms of these technical criteria, samples were collected from two railways built more than 30 years ago, one on sandy soil and the other on stony fine aggregates. Samples of the typical fine silty soil of UNICAMP campus were also collected to evaluate the possibility of using the two types of sub-ballast on this type of soil. The samples collected in the field were tested in laboratory for evaluation of particle size, load capacity and hydraulic conductivity. Finally, the performance of each of the two granular mixtures used as sub-ballast layer in Brazilian railway infrastructures was analysed. [ABSTRACT FROM AUTHOR]

This paper aims to quantify the environmental performance of four typical Brazilian residential buildings with different typologies, through the complete Life Cycle Assessment (LCA) from “cradle to grave”. The LCA considers eight impact categories, including carbon emissions and energy demand. Our analysis includes the relative importance of life cycle phases, construction processes and materials that make the largest contributions to the buildings’ environmental impacts. According to the results, the operational phase is the most critical, the foundation, structure, masonry and coating have the greatest environmental impacts and in terms of materials, concrete, ceramic tiles and steel made the largest contributions. [ABSTRACT FROM AUTHOR]

The selection of an asphalt binder that resists permanent deformation is a challenge, particularly to relate such resistance to the corresponding asphalt mixture behavior in the field. The main goal of this paper is to evaluate the relationship between asphalt binders’ rutting resistance obtained in the laboratory with field observations of mixtures containing those binders. The performances of three monitored test sections were evaluated in Brazil. The rutting resistance of the asphalt mixtures was evaluated in laboratory by the Uniaxial Repeated Load and by the Triaxial Stress Sweep (TSS) tests. The corresponding asphalt binders were tested for the Performance Grade (PG), as well as for the percentage of recovery ( R ) and the non-recoverable compliances ( J nr ) through the Multiple Stress Creep and Recovery (MSCR) test. Rutting performance prediction was conducted using Layered ViscoElastic analysis for Critical Distresses (LVECD) and TSS test results. The results pointed out that the characterization of the asphalt binders by itself is not sufficient to estimate the rutting behavior of the corresponding asphalt mixtures, because of the important role of the aggregates. Nevertheless, poor results in MSCR binder tests tend to indicate mixtures with poor performance (field and laboratory), i.e., the binder test can be used to avoid selecting binders that may lead to permanent deformation. [ABSTRACT FROM AUTHOR]

• FDR-PC review promoting its application and serving as a guide for future research. • Mix design methods are well-established, while structural design methods are limited. • Strength and stiffness data are presented and analysed based on previous research. • The effects of some factors on the behaviour of FDR-PC materials are presented. This paper presents a literature review of full-depth reclamation of pavements with Portland cement (FDR-PC). The paper consists of the following topics: history, construction steps, advantages and disadvantages, mix design, structural design, and behaviour in the laboratory and the field. All sections provide comparisons between international and Brazilian experience. The paper highlights that FDR-PC is used worldwide with significant benefits. While mix design methods are well-established internationally, structural design methods still need to be adapted in most countries. The paper presents ranges of strength and stiffness values based on previous research. Analysis of previous research also identified a suitable test for field modulus prediction and general effects of some characteristics on the behaviour of FDR-PC materials. Furthermore, it identified knowledge gaps for future research, which could promote FDR-PC application with confidence. [ABSTRACT FROM AUTHOR]

This paper analyses the influence of height from the ground on the vertical distribution of marine aerosol salinity for altitudes under the major influence of surf produced aerosol. Results show that the rate of chloride deposition on wet candle decreases drastically when the altitude increases and this relationship can be represented by an exponential decay function, which is influenced by wind regime. A new model is proposed to represent this phenomenon, which is based on the simultaneous influence of the height from the ground and of the wind speeds higher than 3.0 m/s weighted by their residence times. The impact of the salinity decrease with altitude on chloride accumulation into concrete is significant and this should be considered when analysing the performance of vertical concrete structures. [ABSTRACT FROM AUTHOR]

This paper deals with fatigue and complex modulus for three hot mixes. The Brazilian asphalt binders used in this work are classified by penetration grade 10/20, 30/45 and 50/70. It was observed a critical temperature variation in the Cole-Cole plane and in the fatigue test, where the smallest strain for one million cycles occurs at 30 °C for the mixture with penetration grade binder 10/20, and at 20 °C for the mixture with penetration grade binder 30/45, in relation to the mixtures prepared with conventional penetration grade binder 50/70, in which larger viscous component of the modulus normally occurs at 10 °C. [ABSTRACT FROM AUTHOR]

This paper aims to contribute with durability studies by monitoring the unsaturated concrete resistivity over 2 years. Four types of cements commercially used in Brazil were investigated. Some statistical tests (ANOVA and Turkey’s test) were performed to analyze the data. It was found that w/b ratios have no significant influence on the electrical resistivity values of the concrete for a same type of cement. However, the types of cement have a significant effect on resistivity. Cements with blast furnace slag and pozzolan additions have a higher resistivity. Trend lines to estimate the changes in resistivity over time were discovered. [ABSTRACT FROM AUTHOR]

Abstract: The objective of the present paper is to evaluate the thermal performance of diverse wood-based panels in small-scale test cells of 1m×1m×1m of internal volume. The thermal evaluations took place under the climatic conditions of Curitiba, Brazil (latitude 25.5°S, elevation 917m above sea level), which is characterized by a subtropical climate with high daily and annual amplitudes of the air temperature. The research comprised of the following steps: (1) heat flux measurements through each panel configuration; (2) indoor temperature measurements under summer and winter climatic conditions. Reference material for indoor temperature comparisons was a prototype made with ordinary ceramic bricks, plastered on both sides. Air temperature measurements were carried out with data-loggers, heat flux plates were attached to an exposed north facade of each test cell, while incoming solar radiation was measured with an experimental solarimeter. [Copyright &y& Elsevier]

Abstract: After almost 70years of experience in the fiber–cement production in Brazil, Saint-Gobain Brasilit started the non-asbestos production using polyvinyl alcohol (PVA) fiber technology in 2002. Due to PVA costs and availability problems, efforts were done to develop a local high toughness polypropylene (PP) fiber, with improved frictional interface and better dispersion and affinity to Portland Cement matrix. In the last 5years, more than 1.6million tons of asbestos-free corrugated and flat sheets have been produced and commercialized representing about 200million square meters. This paper reviews the alternative fibers for replacing asbestos and the reinforcing model in cement based products. It also presents the Brasilit high toughness polypropylene fibers properties, its manufacturing process and its mechanical performance and improved impact resistance behavior comparing to fiber–cement products available in the Brazilian market. [Copyright &y& Elsevier]

Abstract: The aim of the present paper is to characterize the physical and mechanical properties and to evaluate the thermal performance of wood–cement panels using wood flour originated from lumber industries rejects. The research comprised of several steps: (1) physical and mechanical analysis; (2) heat flux measurements using small-scale test cells of 1m3 of internal volume and (3) indoor temperature measurements under summer and winter climatic conditions in Curitiba, Brazil (latitude 25.5°S, elevation 917m above sea level). Reference material for indoor temperature comparisons was a prototype made with ordinary ceramic bricks, plastered on both sides. Air temperature measurements were carried out with data loggers, heat flux plates were attached to an exposed north facade of each test cell, while incoming solar radiation was measured with an experimental solarimeter. [Copyright &y& Elsevier]

Several times the use of materials with adequate mechanical properties can lead to increases in construction costs. In areas such as the Central-West region of Brazil, where the predominantly fine lateritic soils often require improvement, the investigation of mixtures between the local soil and alternative materials such as Tire Derived Aggregates (TDÁ s) is required. Despite many investigations involving soils and rubber wastes over the years, there is a lack of publication regarding lateritic soils and TDA's. This paper investigated the use of a fine lateritic soil mixed with TDÁs as an alternative composite for light traffic roads and retaining structures. Experiments were conducted in terms of materials characterization, compaction and shear strength properties, quantified using medium-scale direct shear tests. The direct shear tests were based on the compaction tests which showed that the best rubber content was 5%. The results showed that the shear strength highly depends on the level of displacement allowed, which is an important issue once the investigated soil is composed in its majority of fine particles and the occurrence of cracks can limit their use. Finally, the soil studied mixed with TDA's showed potential usage for some civil engineering constructions. [ABSTRACT FROM AUTHOR]

• 31 samples of historical mortars from 5 different buildings were investigated. • It was made a mineralogical, chemical, physical and mechanical characterization. • The mortars had similar components and had different physical and mechanical properties. • Tables and figures summarizing the results are presented. • The results shows the main characteristics and properties of some historical mortars from Northern Brazil. Belém do Pará, founded in 1616, still has layers of lime mortar on its historical buildings, which recurrently need restorative interventions. Intervention strategies need to include the use of building materials compatible with the original materials and, therefore, a good characterization of the original composition is necessary for the restoration of historical monuments. Thus, the main objective of this paper is the chemical, physical, and mineralogical characterization of historical mortars in Belém do Pará from the 18th and 19th centuries, as well as to evaluate their physical and mechanical properties. The results obtained showed the type of mortars used in different buildings and their main components, as well as the mortars behavior that helped the durability of the historic masonries. The conclusions leaded to useful information for seculars mortars restoration of northern Brazil. [ABSTRACT FROM AUTHOR]