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Rice husk (RH) is one of the most commonly grown and consumed cereals in the world. Because of its low nutritional value, it is not commonly used as a food or fertilizer. Instead, it is often burned or landfilled. To develop RH-based composites for thermal and acoustic nonstructural applications, a balance between achieving satisfactory performance in physical and mechanical properties is essential as well as ensuring reliability and predictability in the behavior of the composites. The inclusion of RH in composites can result in increased variability in their performance because of the husk's elastic behavior during compaction and its hydrophilic properties. The RH used in the study was collected from Baixo Mondego, Portugal, and approximately 90 % of the particles had sizes ranging from 1 to 4 mm. To reduce cement usage, different mixtures were produced and categorized based on the use of two types of cement, varying percentages of limestone filler, and different quantities of RH. Robust descriptive and inferential statistics (Student's t-test and Mann-Whitney U test) were employed to analyze the variability of physical and mechanical properties in 10 different RH-based composites. A study was conducted to assess whether a specific mixture formula within a given group exhibited consistent behavior across different batches or yielded intrinsically different results. This helps to identify the key adaptations required in the industrial process of incorporating this biomaterial into composites. The results have shown that it is possible to produce RH-based composites with less variability of performance and potential for nonstructural applications. In this case, cement CEMI/A-L 42.5 R type with limestone filler addition and paste-to-RH ratio by volume between 1.54 and 2.22 was the most sustainable mix design because it had a small variability of results and reduced the cement content. [ABSTRACT FROM AUTHOR]

• Mechanical and durability properties of the recycled concrete with various amounts of crushed concrete waste (CCW). • The effect of CCW's maximum size as partial replacement of natural coarse aggregate (NCA). • Statistical analysis based on the quality performance of concrete. The purpose of this research is to investigate the effect of the incorporation ratio of various maximum sizes of crushed concrete waste (CCW) on the mechanical and durability characteristics of concrete mixes. CCW is undoubtedly one of the main focuses of researchers in the field of sustainable development. However, knowledge regarding the effect of its maximum size on concrete is very scarce. For that purpose, 10 concrete mixes with three different ranges of CCW sizes (5–25 mm), (5–20 mm) and (5–12.5 mm) and different ratios of CCW (0%, 25%, 50%, 75%, and 100%) as replacement of natural coarse aggregate (NCA) were prepared. In addition, compressive and splitting tensile strength, freeze-thaw, water absorption, and abrasion resistance tests were made with the concrete mixes. Since one of the most relevant parts of any experimental investigation is to produce a mathematical relationship between the parameters studied, a statistical analysis was performed, specifically to understand the global effect of the various maximum sizes of CCW as partial replacement of NCA on various characteristics of concrete. The results show that, by incorporating 25% of CCW, the strength of concrete mixes improved for all sizes of CCW. In most cases, for the same incorporation ratio of CCW, the strength and durability (except for abrasion) of concrete slightly improved by decreasing the maximum size of the aggregates. Additionally, the resistance to freeze-thaw cycles results revealed that using CCW instead of NCA can improve the durability characteristics of concrete. [ABSTRACT FROM AUTHOR]

• Cement was replaced up to 15% with forest biomass bottom ashes. • FBA waste can be incorporated in renders without compromising their global behavior. • Similar fresh and water behaviour were found in FBA mortars. • Slightly lower mechanical strengths and more ductility were noticed in FBA mortars. • The incorporation of FBA waste does not affect the scope of the mortar's application. Renewable energies' production is increasing globally over the years. Biomass is considered a renewable source of energy that can be produced by organic matter. The biomass energy production, although generating low CO 2 emissions, creates wastes during the production process, namely ashes. The increase of renewable energies' production and the consequent biomass energy production is also responsible for a higher production of these ashes. Most of these ashes are sent to landfills. This should be avoided since it is responsible for several soil, air and human environmental impacts. The fine ashes particles can lead to respiratory human health problems, as well as contaminate the soils, ground water and the air. Therefore, it is necessary to find new applications for these ashes in order to reduce their deposition in landfills. In this research, an eco-solution is presented to reduce the cement content of the mortars and, at the same time, the biomass deposited in landfill by their incorporation in renders, replacing cement at 5%, 10% and 15%, by volume. The use of biomass ashes in cement-based mortars was investigated through their fresh, water and mechanical behaviour. It was possible to conclude that cement can be replaced up to 15% by a forest biomass ash waste in render applications, without compromising the global behaviour. The incorporation of the waste led to similar fresh and water behaviour to that of a reference mortar, better deformability and slightly lower mechanical strengths, which did not affect the scope of the mortars application, according to EN 998-1. [ABSTRACT FROM AUTHOR]

Abstract CONCRE Top is a novel multi-criteria decision method developed by the authors of this study for concrete optimization, which can be used to optimize either conventional or non-conventional concrete mixes. It can be used to identify the main differences between concrete mixes in terms of three perspectives, namely quality performance, environmental impacts and cost efficiency, and the corresponding causes. The characteristics of concrete fundamentally depend on its target application (e.g. the structural design project). In other words, it depends on the requested characteristics demanded by the consumer. However, this method allows optimizing concrete mixes based on the three mentioned perspectives even if the specific characteristics of concrete for the selected application are unknown. For complicated cases like this one, five scenarios (business as usual, green, strength, service life, and cost) were proposed with different threshold values, in order to cover most of the construction cases (the majority of concrete applications). The major outcome of this method is to provide researchers with a validated approach to support the development of non-conventional materials with optimized technical performance and minimum cost, environmental impact and natural resources' consumption. The method is valid for any case studies and concrete mixes worldwide. Most importantly, this optimization process may change how we take care of the next generation and find sustainable alternative materials for the concrete industry. Highlights • Optimization of conventional and non-conventional concrete mixes • Multi-criteria decision method for concrete selection • Threshold values for quality, environmental impact and cost of concrete mixes • Optimum concrete for various applications and scenarios • Concrete scenarios: business as usual, green, strength, service life and cost [ABSTRACT FROM AUTHOR]

Highlights • Carbonation of concrete mixes with high incorporation ratios of recycled concrete aggregates (RCA), and/or fly ash (FA). • Sequestration of a high amount of CO 2 in concrete, by producing a concrete with high rate of carbonation. • Service life of concrete made with high volumes of FA and RCA. Abstract This paper mainly focuses the effect of high incorporation ratios of fly ash (FA) and recycled concrete aggregates (RCA) on the carbonation resistance of concrete. The aim of using high volumes of these non-traditional materials is to decrease the use of natural resources and capture CO 2. For that purpose, the carbonation resistance of low- and high-strength concrete mixes produced with various incorporation ratios of FA, fine RCA and coarse RCA, jointly and individually, is obtained and related with compressive strength, water absorption and chloride ion penetration. The results show that the carbonation depth of concrete increased up to 3 and 6 times when incorporating 30% and 60% of FA, respectively, and 100% of RCA led to up to 2.7 times increment. Therefore, the concrete cover for mixes made with FA and/or RCA should be increased in order to obtain an equivalent service life to that of conventional concrete. In spite of this fact, it is recommended to incorporate FA in RCA concrete because, in most concrete mixes, the carbonation depth due to the combined effect of both RCA and FA was lower than the sum of the values due to each effect. Additionally, the results show that, although the carbonation rate of concrete mixes containing high volumes of FA and RCA is high, their service life is also relatively high and the concrete reinforcement can be protected for up to 50 years. [ABSTRACT FROM AUTHOR]

Abstract Since concrete is the most widely used construction material in the world, it is important to improve its environmental performance. A possibility is to use supplementary cementitious materials and recycled aggregates. Therefore, the objective of this work is to compare the environmental impacts (EI) of concrete mixes, which contain different incorporation ratios of fly ash (FA) and recycled concrete aggregates (RCA), with and without Superplasticizer (SP). The Life Cycle Assessment methodology was used for environmental assessment, according to ISO 14040 (2006) and EN 15804 (2012). Contrary to most of the previous studies, this one separately obtained the impact for each life cycle stage in detail (e.g. the impact of raw materials production, transportation, and mixing procedure), and explains the reason behind selecting each dataset. Thus, the results of this study can be used for other case studies. The results show that the EI slightly increased when SP was used. Moreover, the incorporation ratio of fine RCA did not change the results for most of the EI categories. Nevertheless, the EI of most of the categories decreased when coarse NA was fully replaced with coarse RCA. Despite the long transportation distance between the coal power plant and the concrete plant considered in the case study, the EI significantly decreased in most categories with increasing amounts of FA. [ABSTRACT FROM AUTHOR]

The use of fine recycled aggregates from recycled concrete is limited due to the high absorption of the material and the subsequent reduction in mechanical performance. At the same time, Self-Compacting Concrete (SCC) uses large amounts of fines to ensure its flowability. Therefore, this type of concrete could allow the use of fine recycled aggregates. Hence, the aim of this work is to study the proportioning and the effects in the microstructure and the fresh basic properties of the use of recycled sand to produce SCC. The concrete mixes analyzed incorporate recycled sand (in percentages of 0%, 20%, 50% and 100%) and natural coarse aggregates. The mix design used an equivalent mortar, which allowed obtaining a suitable concrete that could be at the same time comparable between different replacement ratios and usable in real-life applications. During the design of the mixes with the mortars, the workability was measured from 10 min to 90 min using mini-cone and mini-funnel tests and the suitable ones were chosen to perform self-compacting concrete. Once this was done, these mixes were produced at concrete scale, and with these, basic properties were measured. The fine recycled aggregate changes the workability and the rheology of the mortar and concrete. These differences also affect the microstructure in terms of bonding and porosity distribution. There is a severe reduction of compressive and splitting strength as a result of the use of recycled sand, and this could be linked directly to these changes of the microstructure. The recommended substitution ratio with small decrease of mechanical performance is up to 20%. [ABSTRACT FROM AUTHOR]

High moisture content is a common problem of adhered glazed ceramic cladding. It leads to further problems such as biological growth, delamination and efflorescence. Increased moisture also affects users' indoor comfort and more energy is needed for heating due to higher thermal conductivity. Therefore, it is useful to detect it before visible signs occur and this is possible with infrared thermography. A quasi-quantitative approach based on time-dependent infrared thermographic inspection and thermogram analysis by quantitative methods was tested in an adhered ceramic facade where rising damp had already been identified. Simple image subtraction (SIS), nonnegative matrix factorization (NMF) and principal component analysis (PCA) were the quantitative methods tested for the analysis of thermograms. Hammer-tapping control and surface moisture measurements were the auxiliary techniques used to assess the results. Comparative assessments showed that the quasi-quantitative approach using PCA has great potential to detect changes in moisture and also to eliminate false indications caused by unavoidable reflection and shading. The results obtained by SIS and NMF on the other hand, had limited performance in showing areas with high moisture content. [ABSTRACT FROM AUTHOR]

The built environment represents a high burden in terms of energy consumption. Therefore, it is essential to seek strategies to improve its energy efficiency. Green vertical systems (GVSs) could play an important role in this context as a possible solution to enhance the thermal insulation of buildings. Additionally, GVSs may help to mitigate the urban heat island effect by reducing external surface temperatures and evapotranspiration. In this paper, the authors evaluated the effect of cork-based living walls on the energy performance of buildings and local microclimate. For this purpose, a prototype was built in Portugal, and the temperatures were measured across the system and in its vicinity. A computational fluid dynamics (CFD) model was also used to inspect the thermal behaviour of the system and its effect on the vicinity's microclimate. Finally, real climatic data were used to update a simulation model with the aim of computing the energy needs of a reference building. The results demonstrate that cork-based living walls like the one studied perform well in terms of thermal insulation, and that enhanced evaporative effects could be achieved by moistening the external cork layer. In this case study, reductions of up to 14 °C and 2 °C were recorded, respectively, for the maximum temperatures on the external surface and in the ambient air right in front of the façade. A DesignBuilder model has further shown significantly lower heating and cooling needs (>30%) when a wet cork layer is installed on the exterior of a reference building. • Thermal performance of a living wall assessed under real conditions. • Temperature profile of the living wall and vicinity monitored over one year. • Thermal behaviour and microclimate effect explored by CFD modelling. • Insight into the energy savings simulated with DesignBuilder software. • Lower heating and cooling needs provided by the living wall. [ABSTRACT FROM AUTHOR]

Abstract: Studies on selective demolition (also named deconstruction) in the past few years have produced some high quality economic, material and environmental information. Economic data, however, varies considerably between regions since local conditions strongly influence labour costs, tipping fees and/or market prices for recovered materials. Regional financial and regulatory constraints will bind the economic viability of conventional and selective demolition choices, which are essentially economic in a free market. Given this, the present study evaluates the economic implications of the two demolition types by analyzing a case study in Portugal. A few scenarios are considered, based on possible waste management options, some of which favour selective demolition over the conventional type. [Copyright &y& Elsevier]

In a previous work, the authors of this paper proposed a new modular living wall made with expanded cork agglomerate, fully describing the designing process and discussing the overall mechanical performance. It was then shown that several key environmental and functional requirements were met by favouring the use of insulation cork board (ICB), a thermal insulation material with low environmental impact and good water retention. In this paper, the authors have extended the characterization of that living wall system to assess its performance under real conditions, with different plant species, geographical orientations and seasons. For this purpose, a prototype was built with four façades, facing north, south, east, and west. The area of façade covered by vegetation and the carbon sequestration provided by two different plant species were then monitored for over a year. Annual values of carbon uptake, experimentally determined, were further used to update an environmental life cycle model of the system. The results suggest that this modular living wall performs well in terms of plant development and carbon sequestration, with Festuca glauca showing a higher cumulative carbon uptake and a higher percentage of façade coverage than Thymus pulegioides , regardless of the geographical orientation and season. This essentially results from the greater amount of biomass produced by Festuca glauca and its hanging behaviour. It was also concluded that this new modular living wall is an eco-friendly choice, when assessed from a life cycle perspective, since it has a negative carbon balance over its life cycle (22.7 kg CO 2 eq per square meter). • Innovative cork-based living wall tested under real conditions. • Annual carbon uptake up to up 371 g C/m2 experimentally confirmed. • Negative carbon balance of 22.7 kg CO 2 eq/m2 over the life cycle. • Modular living wall with improved environmental performance. [ABSTRACT FROM AUTHOR]

Green vertical systems (GVSs) can offer several benefits, both for buildings by increasing their thermal and acoustic insulation, and for the urban environment by enhancing the biodiversity, improving the air quality, and reducing the heat island effect. Despite all these benefits, the effective sustainability of these systems has been questioned when assessed from a life cycle perspective. This is largely because of the environmental impacts related to the components and materials used in the construction of such solutions, but also due to irrigation and maintenance needs. In this work, the authors describe the design process for a new modular GVS based on insulation cork boards (ICBs). A comparative life cycle analysis (LCA) of several GVSs was first carried out to identify the environmental hotspots of most concern related to the product phase. Based on the conclusions of the LCA and a set of additional functional requirements, the authors then proposed a new ICB module to build a GVS with better environmental performance. Since ICBs can be produced with different mass densities, with distinct environmental impacts and manufacturing costs, a full mechanical characterization was also carried out to assist in choosing the most suitable ICB density. The results suggest that ICB modules of medium density (140–160 kg/m3) can be an appropriate eco-friendlier alternative to current plastic- and metal-based GVSs, fully complying with the environmental and functional requirements that would be expected for a living wall system. • Design process of a new modular living wall made of expanded cork agglomerate. • Innovative module with intrinsic thermal insulation and water retention functions. • Modules of 140–160 kg/m3 fully meet the expected mechanical requirements. • Eco-friendlier alternative to plastic- and metal-based green vertical systems. [ABSTRACT FROM AUTHOR]

• PEF calculation and report method conflict with existing LCA standards. • The revision of EN 15804 intents to harmonized it with PEF. • Suggestions for the update of PEF converge with existing standards in some aspects. • After the update of PEF method and revision of EN 15804, there are still divergences. The environmental performance of construction products and assemblies is a determinant factor for the environmental sustainability of buildings. Increasing willingness of stakeholders in the construction sector for green procurement, better-informed decisions and consideration of environmental aspects increase the need of transparent, objective and independent information on the environmental performance of construction products. Environmental product declarations EPD based on the European standard EN 15804 are used in the construction sector since 2012. In parallel, since 2011, the European Commission EC has developed a common method for the assessment of the environmental performance of products: the Product Environmental Footprint PEF. After a pilot phase, the PEF method has evolved, and some updates were published in early 2019. The EN 15804 standard has also been revised, and therefore it is the ideal time to seek the harmonization of Life Cycle Assessment LCA methods. This paper presents a pioneer study applied to the construction sector that focus on the comparison between the PEF method 2019 updated and the EPDs developed according to the Core rules for the product category of construction products presented in EN 15804 EN 15804:2012+A1:2013, recently updated by EN 15804:2012+A1:2013 +A2:2019. The comparison was performed by listing and analysing key requirements of both methods and their updates. From the results, it was possible to conclude that the methods have very distinct requirements that make the comparison of results or the alternate use of PEFs and EPDs impossible, for instance, in the decision-making process. This highlights the need of harmonisation and therefore the discussion includes the presentation of a roadmap to update the PEF method and the EN 15804 standard so that results can be more coherent and comparable. [ABSTRACT FROM AUTHOR]