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This research focuses on a comparison of 20 external wall systems that are conventionally used in Spanish residential buildings, from a perspective based on the product and construction process stages of the life cycle assessment. The primary objective is to provide data that allow knowing the environmental behavior of walls built with materials and practices conventionally. This type of analysis will enable promoting the creation of regulations that encourage the use of combinations of materials that generate the most environmentally suitable result, and in turn, contribute to the strengthening of the embodied stages study of buildings and their elements. The results indicate that the greatest impact arises in the product stage (90.9%), followed by the transport stage (8.9%) and the construction process stage (<1%). Strategies (such as the use of large-format pieces and the controlled increase in thickness of the thermal insulation) can contribute to reducing the environmental impact; on the contrary, practices such as the use of small-format pieces and laminated plasterboard can increase the environmental burden. The prediction of the environmental behavior (simulation equation) allows these possible impacts to be studied in a fast and simplified way.

The difficult current environmental situation, caused by construction industry residues containing ceramic materials, could be improved by using these materials as recycled aggregates in mortars, with their processing causing a reduction in their use in landfill, contributing to recycling and also minimizing the consumption of virgin materials. Although some research is currently being carried out into recycled mortars, little is known about their stress-strain (σ-ε); therefore, this work will provide the experimental results obtained from recycled mortars with recycled ceramic aggregates (with contents of 0%, 10%, 20%, 30%, 50% and 100%), such as the density and compression strength, as well as the σ-ε curves representative of their behavior. The values obtained from the analytical process of the results in order to finally obtain, through numerical analysis, the equations to predict their behavior (related to their recycled content) are those of: σ (elastic ranges and failure maximum), ε (elastic ranges and failure maximum), and Resilience and Toughness. At the end of the investigation, it is established that mortars with recycled ceramic aggregate contents of up to 20% could be assimilated just like mortars with the usual aggregates, and the obtained prediction equations could be used in cases of similar applications.

Currently, few studies have compared the variations in environmental impact throughout the different stages of the life cycle of urban construction elements; and of these, only a minority approach it from the perspective of favoring mobility on a human scale and reducing the space allocated to motorized traffic flow. This study, by means of quantitative data, shows the environmental implications associated with prioritizing the non-motorized mobility of a city's inhabitants during the design process of an urban construction element, the residential street (referring to the stages of the production and the construction process: the "cradle to handover" approach). An emerging methodology in urban themes was used in order to obtain the environmental analysis: Life Cycle Assessment (LCA). The results show that the increase in the human scale and the favoring of non-motorized mobility generate a lower environmental impact (considering the same uses of materials for the different zones of analysis). Additionally, it was possible to establish the influence that the specific use of materials employed in the construction of the streets may have, as well as the importance that an LCA acquires in the design of the urban environment.

Recycled concrete aggregate (RA) from pavement demolition was used to make concrete. Ten concrete mixtures with different replacement percentages of RA (coarse and fine) were made. The corrosion rate of steel and the electrical resistivity of concrete were determined on reinforced concrete specimens subjected to wetting-drying cycles (3.5% solution of NaCl). Corrosion rate was determined using the electrochemical technique of linear polarization resistance, while the electrical resistivity was measured by electrochemical impedance spectroscopy. The results show that the use of RA introduces more interfaces in concrete, which accelerates the steel corrosion process because the porosity increases and the electrical resistivity decreases. However, steel corrosion and the electrical resistivity in concrete are not significantly influenced by replacing a maximum 30% of coarse aggregate or 20% of fine aggregate with RA.

This study presents a comparative analysis of the housing indicators used by the singlefamilyhousing rating systems (SHRSs), in which the residential urban environment (RUE)influences buildings’ certification scores, emphasizing the relationships of six systems developedby middle‐income countries (MICs)—BEST, CASA, GBI, BERDE, Green Homes, and LOTUS—andthe two most‐recognized rating systems, BREEAM and LEED. The aim is to provide new housingindicators that are capable of bringing the concept of sustainability into the cities of MICs. Theresults reveal that the percentage of influence that single‐family housing (SFH) can achieve in themetric established by each system is relatively low. However, considering all of the identifiedindicators, this influence could increase to 53.16% of the total score in multi‐criteria evaluations.Furthermore, a significant lack of indicators for mandatory criteria evaluations was found, withCASA being the only system that considers their inclusion. This paper identifies 37 indicators formulti‐criteria assessments and two for mandatory‐criteria assessments, providing new perspectiveson several topics. Furthermore, the methodology established to obtain the indicators could be usefulfor other researchers in the identification of new sustainable indicators.

Recycled aggregates (RA) from construction and demolition can be used in permeable concretes (PC), improving the environment. PCs have a significant porous network, their cement paste and the interaction between the paste and the RA establishing their strength. Therefore, it is important to evaluate the porosity in the interfacial transition zones. The porosity of the cement paste, the aggregate and the interfacial transitional zones (ITZ) of a PC with recycled coarse aggregates (RCA) and silica fume (SF) is measured by means of image analysis–scanning electron microscope (IA)-(SEM) and by mapping the chemical elements with an SEM-EDS (energy dispersive spectrometer) detector microanalysis linked to the SEM and, as a contrast, the mercury intrusion porosimetry technique (MIP). In the IA process, a “mask” was created for the aggregate and another for the paste, which determined the porosity percentage (for the anhydrous material and the products of hydration). The results showed that using SF caused a reduction (32%) in the cement paste porosity in comparison with the PC with RA. The use of RA in the PC led to a significant increase (190%) in the porosity at different thicknesses of ITZ compared with the reference PC. Finally, the MIP study shows that the use of SF caused a decrease in the micropores, mesopores and macropores.

In this work, the mechanical properties and microstructural features of an AISI 304L stainless steel in two presentations, bulk and fibers, were systematically studied in order to establish the relationship among microstructure, mechanical properties, manufacturing process and effect on sample size. The microstructure was analyzed by XRD, SEM and TEM techniques. The strength, Young’s modulus and elongation of the samples were determined by tensile tests, while the hardness was measured by Vickers microhardness and nanoindentation tests. The materials have been observed to possess different mechanical and microstructural properties, which are compared and discussed.