This paper presents a research on the environmental impacts of particleboards produced from wastes, based on a comparative Life Cycle Assessment study. The particleboards were manufactured in ...laboratorial scale from the following residues: sugarcane bagasse (Saccharum spp.) and pine wood shavings (Pinus elliottii). The study was developed following the methodological guidelines of ISO 14040. The functional unit adopted was the m2 of the particleboards produced and the impacts were evaluated by the Environmental Development of Industrial Products method. The results indicated that pine particleboard present the highest environmental impact potential. Our findings suggested that the factors that mostly aggravated the environmental impacts were: the distance between the raw materials and the production site, and formaldehyde emissions (FE). The first is related to the combustion of fossil fuel during the acquisition of raw material, which achieved the values of 2185.94 g/m2 for consumption of non-renewable resources for pine particleboard and 893.53 g/m2 for bagasse particleboard. The second is related to the use of urea-formaldehyde resin, responsible for the FE into the air during production. The FE is accountable for the contamination of approximately 7,800,000.00 m3 of air per m2 of particleboard produced, and was the factor with the greatest impact in human toxicity potential.
•Environmental aspects of production of particleboards made of residues.•Consumption of resources, energy, and emissions were analyzed.•Environmental Development of Industrial Products (EDIP) method was used to perform Life Cycle Assessment.•Raw materials distance of transport had a significant environmental impact.•Urea-formaldehyde resin had the most environmental impact of all.
A large part of the European building stock was built before implementing the recent energy and structural codes, resulting in buildings characterized by deficiencies in terms of comfort, energy ...savings and structural safety. The retrofitting and rehabilitation of the existing building stock need to be adequately performed, aiming to improve the seismic and energy performance simultaneously. The work summarized here is dedicated to defining priority scenarios for buildings’ retrofitting to improve the seismic safety and energy efficiency of the European Union (EU) building stock. First, the state of the EU building stock is analysed in terms of buildings’ age, types of structures, energy efficiency, energy consumption and energy poverty. Then, the EU climate demands are presented, namely the regions with higher temperature variations, i.e., heating or cooling degree days. The EU seismic risk is also presented and discussed in terms of average annual losses, average annual economic losses and average annual life losses. Based on these input parameters, nine seismic–climate regions in the EU are proposed using a simplified approach. Finally, retrofitting scenarios are proposed for two types of buildings (i.e., masonry and reinforced concrete) based on their seismic–climate region.
► Study of a new sustainable building material. ► Textile wastes reuse. ► Innovative sustainable solutions for non-structural applications (thermal insulation).
The adoption of more sustainable ...behaviors, particularly in what concerns to the reduction of energy consumption and the emissions of greenhouse gases, is nowadays a priority. The construction sector is one of the key areas of intervention, which carries a high consumption of resources such as materials, energy, and water. Thus, it is essential to adopt more efficient actions during all stages of the construction process, including the use of more sustainable materials. The reuse of different types of waste in the construction or rehabilitation of buildings can contribute significantly to sustainability.
In this research work, the potential applicability of woven fabric waste (WFW) and a waste of this residue, named woven fabric subwaste (WFS), as thermal insulation building material was studied. Experimental work was conducted using an external double wall, with the air-box filled with these two types of waste, to determine their thermal characteristics. Two heat flowmeters and four surface temperatures sensors were placed on the wall surface to determine the thermal conductivity of the wastes.
The obtained results show that the application of the WFW and WFS in the external double wall increases its thermal behavior in 56% and 30%, respectively.
The thermal conductivity value of the WFW is similar to the values obtain for expanded polystyrene (EPS), extruded polystyrene (XPS) and mineral wool (MW). The value of this parameter for the WFS is approximately equal to the values for granules of clay, vermiculite or expanded perlite. Therefore, applying these wastes as a possible thermal insulation material seems to be an adequate solution. Environmental, sustainable and economical advantages may result from this practice.
•Six cyclic in-plane tests were performed on typically confined masonry (CM) walls.•Simplified bi-linear curves are proposed to represent the seismic capacity of walls.•An elastic equivalent viscous ...damping of 6.25% is recommended for CM walls.•A database of different experimental tests on Peruvian CM walls aimed to compute fragility curves.•Horizontal bars placed inside the CM walls improve the whole displacement ductility.
Around 56% of dwellings in Lima are constructed with confined masonry walls, and over 70% are built without engineering design and supervision. This building stock is exposed to the seismic activity of the Peruvian coastline. Then, in case of a severe earthquake, many of these buildings may suffer significant damage and eventually collapse, causing high economic losses and fatalities. Thus, it is essential to investigate the seismic behaviour of these constructions to understand their seismic vulnerability. This work studied the seismic performance of typically confined masonry walls built with hollow bricks based on cyclic in-plane tests. The imposed boundary conditions allowed the walls to behave as a cantilever. The influence of vertical pre-compression was also explored by performing separate tests with and without such load. Outcomes suggest that these walls may collapse after 0.5% drift. Also, mechanical features like stiffness degradation and damping values were calculated for different displacement limit states. Finally, fragility curves of confined masonry walls considering different unit types (i.e. solid, hollows, tubular), axial load ratio, and horizontal reinforcement are computed. The results demonstrate that tubular units should be forbidden as bearing walls, and horizontal reinforcement inside the walls improves their displacement ductility.
A new generation of self-compacting earth-based composites (SCEC) for vertical elements with fully exposed earth, in which the main feature is the elimination of compaction, is proposed in the ...current work. The first objective was to develop earth-based mixture compositions with locally available raw materials and achieve self-compactability. A Portuguese soil, typically employed in rammed earth construction, was stabilised using cementitious materials and a superplasticiser to ensure flowability. The mixture design studies allowed to achieve flowable fresh composites. Results on the hardened state showed that SCEC presents high compressive strengths (5–14 MPa). The electrical resistivity SCEC increased with time and achieved at least 5600 Ωm at 28 days, while mass loss stabilised after 14 days in a controlled environment room. Additional tests were performed on selected optimal SCEC mixtures: drying shrinkage and water capillary absorption, with promising results. Overall, this work provided initial boundaries for the mixture design and assessment of SCEC and opened the door for further studies on new and novel earth materials construction techniques.
Currently, the upgrade of existing reinforced concrete (RC) buildings focuses only on energy retrofitting measures due to the current policies promoted in the scope of the European Green Deal. ...However, the structural deficiencies are not eliminated, leaving the building seriously unsafe despite the investment, particularly in seismic-prone regions. Moreover, the envelopes of existing RC buildings are responsible for their energy efficiency and seismic performance, but these two performance indicators are not usually correlated. They are frequently analyzed independently from each other. Based on this motivation, this research aimed to perform a holistic performance assessment of five different types of masonry infill walls (i.e., two non-strengthened walls, two walls with seismic strengthening, and one wall with energy strengthening). This performance assessment was performed in a three-step procedure: (i) energy performance assessment by analyzing the heat transfer coefficient of each wall type; (ii) seismic performance assessment by analyzing the out-of-plane seismic vulnerability; (iii) cost–benefit performance assessment. Therefore, a global analysis was performed, in which the different performance indicators (structural and energy) were evaluated. In addition, a state-of-the-art review regarding strengthening techniques (independent structural strengthening, independent energy strengthening, and combined structural plus energy strengthening) is provided. From this study, it was observed that the use of the external thermal insulation composite system reduced the heat transfer coefficient by about 77%. However, it reduced the wall strength capacity by about 9%. On the other hand, the use of textile-reinforced mortar improved the strength and deformation capacity by about 50% and 236%, but it did not sufficiently reduce the heat transfer coefficient. There is a need to combine both techniques to simultaneously improve the energy and structural energy performance parameters.
The recent seismic activity highlights the crucial need to enhance seismic design and safety assessment methods, particularly for irregular structures, in both new and existing constructions. The ...present study focuses on structural irregularities in elevation for buildings, as the design of structural systems involves multiple variables that often result in irregularities in many buildings. This work aims to perform a comparative assessment of the criteria adopted for the evaluation of the structural irregularities in elevation present in European and international seismic codes. This paper is structured as follows: Firtsly, it discusses structural irregularities and more specifically the most common types of structural damage due to seismic events. Then, it shows the documented experiences of structural damages in seismic events associated with structural irregularities in China, Italy, Spain, Nepal and Mexico. Additionaly, it discusses the requirements of the standards on irregularities and their limitation in that matter. At the end of this section, the different approaches of each code in irregularities in elevation are compared. All assessed seismic codes addresses the structural irregularity issue, attributing the desired characteristics of a seismic-resistant structure. However, there are considerable development differences between norms, demonstrated on ambiguity of few codes on criteria of vertical irregularies.
The use of simpler and less bulky equipment, with a reliable performance and at relative low cost is increasingly important when assembling sensing configurations for a wide variety of applications. ...Based on this concept, this paper proposes a simple, efficient and relative low-cost fiber Bragg grating (FBG) interrogation solution using ultra-short FBGs (USFBGs) as edge filters. USFBGs with different lengths and reflection bandwidths were produced in silica optical fiber and in
(PMMA) microstructured polymer optical fiber (mPOF), and by adjusting specific inscription parameters and the diffraction pattern, these gratings can present self-apodization and unique spectral characteristics suitable for filtering operations. In addition to being a cost-effective edge filter solution, USFBGs and standard uniform FBGs in silica fiber have similar thermal sensitivities, which results in a straightforward operation without complex equipment or calculations. This FBG interrogation configuration is also quite promising for dynamic measurements, and due to its multiplexing capabilities multiple USFBGs can be inscribed in the same optical fiber, allowing to incorporate several filters with identical or different spectral characteristics at specific wavelength regions in the same fiber, thus showing great potential to create and develop new sensing configurations.
The primary objective is to present the most representative types of damage observed in reinforced concrete (RC) structures due to earthquakes. Those damages are divided according to the ten most ...representative types. Examples and the main reasons that could trigger each failure mechanism are presented. The definition of these damage types is supported by post-earthquake damage reconnaissance missions in Sichuan (China) in 2008, L’Aquila (Italy) in 2009, Lorca (Spain) in 2011, Emilia-Romagna (Italy) in 2012, Gorkha (Nepal) in 2015, Muisne (Ecuador) in 2016 and Chiapas (Mexico) in 2017. An extensive discussion is presented concerning the infill walls’ seismic behaviour and their interaction with the RC structural elements. The presentation of the significant learnings and findings concerning the typical damage herein presented and discussed are compared with the common Southern European construction practice. The impact of the infill walls on the rehabilitation costs of damaged RC buildings is also studied. These costs are compared to those related to the structural damage and rehabilitation of the entire building structure to understand the impact of the infill walls. Finally, a case study is presented to study the effect of implementing simplified retrofitting strategies to prevent the soft-storey mechanism, one of the most common problems observed in past earthquake events.
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