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This study examines cement and ceramic waste (CW) for the sub-base layer of roads. This innovative method can do away with the risks associated with improper disposal of industrial waste. To achieve this objective, several proportions of cement and CW were used, ranging from 1.5 to 2% and 5% to 15%, respectively. The aim of the work was to examine the influences of CW and ordinary Portland cement (OPC) on the unconfined compressive strength (UCS), permeability, consolidation, and microstructures of untreated and treated soil of road sub-base layer. The Guelph permeameter, UCS, permeability, and one- dimensional consolidation were among the laboratory and in-situ tests that were examined; the microstructures were characterised using SEM, infrared (IR), and mercury intrusion porosimetry (MIP). The findings indicated that the high permeability of the natural soil caused harm to our road soon after construction. Applying 5 to 15% CW reduced permeability by approximately 100% and settlement by around 43%. Furthermore, under wet and immersed conditions, mixing CW and OPC with soil raised UCS by approximately 182% and 20 times, respectively. This study demonstrated that by enhancing the geotechnical properties of soil, CW and OPC combined with it could be used as a road sub-base layer material.

This study has focused on the dam sediments and marble waste reuse as subgrade materials for road construction, with the overarching goals of reducing greenhouse gas emissions and conserving natural resources. Different mixtures were prepared based on sediments and marble waste, and treated with hydraulic binders. The first mixture consisted solely of raw sediment, while the second mixture combined 50 % dredged sediments with 50 % marble waste. Additionally, this mixture was treated with 1 % aerial hydrated lime and hydraulic road binder to enhance its properties. The experimental study focused on assessing both the short-term and long-term mechanical properties of the prepared mixtures. Results highlighted that the mixtures containing dam sediments and marble waste were highly suitable for road subgrade construction. These mixtures satisfied the criteria for trafficability (UCS), wetting resistance (UCSI), freezing resistance (ITS), and overall mechanical strength. Furthermore, a comprehensive analysis of the mixtures' microstructure and their environmental impact was conducted. A significant relationship was observed between CaO/SiO2 ratio and the mechanical properties of the treated mix. The research contributes to the growing body of knowledge regarding sustainable construction practices by highlighting the viability of utilizing dredged sediments and marble waste as valuable resources in road subgrade construction. The study showed that recovering 20 % of sediment and marble waste to replace natural materials would reduce energy consumption and greenhouse gas emissions by at least 40 % and 28 % respectively.

This study underscores the potential of utilizing natural volcanic tuffs (NVTs) as supplementary cementitious materials (SCMs) in alignment with global sustainability efforts aimed at mitigating the cement industry’s negative impacts on both the economy and the environment. Experimental investigations were conducted on concrete mixtures containing 10%, 20%, 30%, 40%, and 50% NVT as partial cement replacements to assess their influence on concrete’s mechanical and microstructural properties. Based on the findings, concrete samples with 10% NVT replacements exhibited increased flexural and compressive strengths of 35.6% and 5.6%, respectively, compared with ordinary concrete after 28 days. The depth of water penetration in the concrete samples was significantly reduced by the inclusion of NVT, with a maximum reduction of 56.5%. Microstructural analysis using scanning electron microscopy (SEM) revealed enhanced densification of the concrete microstructures, attributed to the high pozzolanic activity of NVT use in cement-based composites. Analysis of variance (ANOVA) revealed statistically significant relationships between NVT content and both the compressive and flexural strengths of the concrete samples. In conclusion, substituting 10% cement with NVT not only enhances the mechanical properties of concrete but also decreases the energy demand for cement production and reduces carbon dioxide (CO2) emissions, thus contributing to more sustainable construction practices.

As urbanization increases, buildings require greater amounts of energy for heating and cooling, thereby necessitating the search for effective solutions. The courtyard is often considered a viable option; however, the limited availability and high cost of land resulting from rapid urbanization hinder its widespread use. Consequently, a courtyard with a cluster of buildings is proposed as a feasible solution to address land scarcity. Nonetheless, further investigation is required to effectively integrate this solution into neighborhood urban planning. This study examines the influence of three variables—courtyard orientation, courtyard size, and the arrangement of buildings around the courtyard—on the provision of cooling and heating for buildings. The research focuses on 216 experimental scenarios simulated using Revit software, which excels in its ability to accurately interpret input data and conduct real-time analysis depending on the variables of the building design. The results were recorded for the facades and ground, and the shaded area was computed for each scenario; following these measurements, the shadow areas on both the facade and ground were converted into percentages. The testing involved a group of buildings surrounding courtyards of four different shapes (square, rectangle, triangle, and circle). This approach aimed to identify the most efficient design for implementation in neighborhood planning contexts. The findings indicate that the shape of the courtyard significantly impacts cooling and heating of buildings. Specifically, the square courtyard is unsuitable for countries with Mediterranean climates, such as Jordan, as it can reduce shade coverage by 30%, leading to higher temperatures. Conversely, employing a rectangular courtyard results in a higher proportion of shadows compared to other shapes. The study further demonstrates the influence of the examined variables on the efficacy of the courtyard in cooling and heating of buildings.

This paper aims to study the drying and autogenous shrinkage of optimized One-Part-Geopolymer binders based on micronized dredged sediments and fly ash. Four One-Part-Geopolymer with 0, 15, 30 and 50% wt of sediments and fly ash were optimized by the variation of SiO2/Al2O3 molar ratio between 3; 3.5; 4; 4.5; 5. Findings shown that the sediments incorporation increases the mechanical strength and decreases the matrix pore size. This improvement is related to two phenomena: the fineness of the sediments which plays the role of nucleation zone in the matrix, and the coexistence of C-A-S-H and N-A-S-H gels as shown by the SEM-EDS. The reduction in the pore size of mortars with the addition of sediments leads to an increase in drying and autogenous shrinkage which have been linked to pore distribution rather than mass loss, unlike ordinary cementitious materials. However, the shrinkage values are still lower than the literature findings.

Slag is produced in enormous amounts by steelworks, which are scrap metal recycling industries that produce steel wire rods and steel reinforcing bars. In the absence of a sustainable recovery route, the latter pose a possible environmental risk. This work is concerned with the valorization of this by-product in the production of concrete pavers. To accomplish so, the slag was previously evaluated using X-ray fluorescence, particle size analysis, density, absorption coefficient, and other criteria that are recommended for usage in this field. The pavers were then manufactured using the Dreux Gorisse recipe, with slag substituting the gravel. The results demonstrate that the slag is rich in iron, which is characterized by lime, silica, and magnesia rates of 31.73%, 16.33%, and 16.33%, respectively, low percentages of manganese and alumina. The water absorption rate is between 2.6% and 2.8%, and their density is similar to 3.6 kg/l. Los Angeles has a 20-coefficient. As a result of their inclusion in the design of the pavers, they were able to split in line with the NF EN 1338 standard and retained a reasonable degree of tensile strength.

In the absence of industry data, organisms, and researchers leverage free and available data, specifically building and demolition permits. Geospatial processing is essential to integrate information from various files into a single GIS layer containing all relevant attributes for analysis. This article proposes a Geographic Information System (GIS) processing model aimed at monitoring construction and demolition dynamics in the European metropolis of Lille to quantify the urban production of mineral waste from buildings. Author methodology is based on that that the deposit potential can be analyzed using the observation of the spatiotemporal dynamics of building and demolition permits. The results demonstrate that combining construction and demolition (C&D) permits with other GIS layers allows us to produce data to quantify demolition surfaces per year in a given French area. The applicability of this methodology extends to all French regions, providing insights into the impact of crises on deconstruction activities and C&D waste generation. The study focuses on C&D French public data bases (French government and European Metropolis of Lille) attributed to the region (area) of the European Metropolis of Lille (MEL) between 2013 and 2022. Some data for 2022 were incomplete due to ongoing treatment, emphasizing the importance of understanding the dynamics of demolition rates or surfaces to identify data gaps or errors. Historical trajectories of C&D permits were quantified and analyzed, revealing over 21,000 permits granted from 2013 to 2022, categorized by site type (new construction, rehabilitations, prior declarations, and demolitions). Construction sites during this period covered approximately 3,345,948 m2, constituting 20% of the MEL’s building stock, while demolition sites amounted to 1,977,911 m2, equivalent to 5% of the total area of buildings in the metropolis. Employing GIS allowed for a spatial analysis, visualizing data by municipality, urban fabric, and year. The analysis highlighted territories with high and low potential for demolition and construction, as well as the most impacted urban fabrics and dynamic periods. The article discusses potential crisis impacts (e.g., COVID-19 or economic downturns) and the implications of incomplete data. Finally, the study demonstrates how these findings can be utilized to quantify C&D waste, leveraging GIS and the production rate calculation method (GRC).

La particularité identitaire de l'enfant de migrants vient révéler une certaine vulnérabilité lors du processus identitaire à l'adolescence qui peut venir réveiller des transmissions inconscientes inter- et transgénérationnelles capables de se nicher au sein des symptômes de l'adolescent. L'objectif de l'étude présentée dans cet article est de mettre en évidence, à partir du dispositif thérapeutique des consultations transculturelles, les leviers thérapeutiques permettant une mise en récit et une transmission consciente de l'histoire familiale et culturelle et de penser à leur transposition vers d'autres dispositifs. L'étude montre le soutien qu'apporte la consultation transculturelle afin de permettre aux familles de mettre des mots sur l'histoire familiale. Même si certaines spécificités du dispositif transculturel ne sont pas exportables à d'autres, des espaces thérapeutiques groupaux ou individuels peuvent se saisir des leviers thérapeutiques mis en lumière. Many studies have highlighted the psychological impact and resulting vulnerability inherent in being second-generation immigrant (SGI) children. Some studies have also demonstrated that the symptoms of SGI adolescents can be the manifestations of traumas that have been unconsciously transmitted from one generation to another. The purpose of the research presented in this article is to investigate the different therapeutic processes and tools used by therapists during transcultural therapy to support conscious intergenerational and transgenerational transmission in their care of SGI adolescents and their participating family members. The monitoring of three patients, SGI adolescents, of different ages and origins, provided data that were analyzed using a clinical and transcultural qualitative method. The analysis of 10 sessions of transcultural psychotherapy with each SGI adolescent patient reveals, first of all, that this therapeutic device is illustrative in the care of SGI children suffering from the symptoms of inter- and transcultural transmissions of trauma. It also highlights various therapeutic levers and approaches to transcultural counseling that can enable families to consciously unveil their family and cultural histories. This research project also proposes a methodology where the inter- and transgenerational transmissions can be adapted to favor the healthy development of SGI adolescents' identity and that can also be applied in other group or individual therapeutic devices. [ABSTRACT FROM AUTHOR]

This study underscores the potential of utilizing natural volcanic tuffs (NVTs) as supplementary cementitious materials (SCMs) in alignment with global sustainability efforts aimed at mitigating the cement industry's negative impacts on both the economy and the environment. Experimental investigations were conducted on concrete mixtures containing 10%, 20%, 30%, 40%, and 50% NVT as partial cement replacements to assess their influence on concrete's mechanical and microstructural properties. Based on the findings, concrete samples with 10% NVT replacements exhibited increased flexural and compressive strengths of 35.6% and 5.6%, respectively, compared with ordinary concrete after 28 days. The depth of water penetration in the concrete samples was significantly reduced by the inclusion of NVT, with a maximum reduction of 56.5%. Microstructural analysis using scanning electron microscopy (SEM) revealed enhanced densification of the concrete microstructures, attributed to the high pozzolanic activity of NVT use in cement-based composites. Analysis of variance (ANOVA) revealed statistically significant relationships between NVT content and both the compressive and flexural strengths of the concrete samples. In conclusion, substituting 10% cement with NVT not only enhances the mechanical properties of concrete but also decreases the energy demand for cement production and reduces carbon dioxide (CO2) emissions, thus contributing to more sustainable construction practices. [ABSTRACT FROM AUTHOR]

This study examines cement and ceramic waste (CW) for the sub-base layer of roads. This innovative method can do away with the risks associated with improper disposal of industrial waste. To achieve this objective, several proportions of cement and CW were used, ranging from 1.5 to 2% and 5% to 15%, respectively. The aim of the work was to examine the influences of CW and ordinary Portland cement (OPC) on the unconfined compressive strength (UCS), permeability, consolidation, and microstructures of untreated and treated soil of road sub-base layer. The Guelph permeameter, UCS, permeability, and onedimensional consolidation were among the laboratory and in-situ tests that were examined; the microstructures were characterised using SEM, infrared (IR), and mercury intrusion porosimetry (MIP). The findings indicated that the high permeability of the natural soil caused harm to our road soon after construction. Applying 5 to 15% CW reduced permeability by approximately 100% and settlement by around 43%. Furthermore, under wet and immersed conditions, mixing CW and OPC with soil raised UCS by approximately 182% and 20 times, respectively. This study demonstrated that by enhancing the geotechnical properties of soil, CW and OPC combined with it could be used as a road sub-base layer material. [ABSTRACT FROM AUTHOR]

As urbanization increases, buildings require greater amounts of energy for heating and cooling, thereby necessitating the search for effective solutions. The courtyard is often considered a viable option; however, the limited availability and high cost of land resulting from rapid urbanization hinder its widespread use. Consequently, a courtyard with a cluster of buildings is proposed as a feasible solution to address land scarcity. Nonetheless, further investigation is required to effectively integrate this solution into neighborhood urban planning. This study examines the influence of three variables—courtyard orientation, courtyard size, and the arrangement of buildings around the courtyard—on the provision of cooling and heating for buildings. The research focuses on 216 experimental scenarios simulated using Revit software, which excels in its ability to accurately interpret input data and conduct real-time analysis depending on the variables of the building design. The results were recorded for the facades and ground, and the shaded area was computed for each scenario; following these measurements, the shadow areas on both the facade and ground were converted into percentages. The testing involved a group of buildings surrounding courtyards of four different shapes (square, rectangle, triangle, and circle). This approach aimed to identify the most efficient design for implementation in neighborhood planning contexts. The findings indicate that the shape of the courtyard significantly impacts cooling and heating of buildings. Specifically, the square courtyard is unsuitable for countries with Mediterranean climates, such as Jordan, as it can reduce shade coverage by 30%, leading to higher temperatures. Conversely, employing a rectangular courtyard results in a higher proportion of shadows compared to other shapes. The study further demonstrates the influence of the examined variables on the efficacy of the courtyard in cooling and heating of buildings. [ABSTRACT FROM AUTHOR]

Large quantities of dredged sediments and recycled concrete materials are generated every year all over the world. The disposal of these large quantities in landfills represents serious environmental problems. Furthermore, high-quality raw materials for construction are depleting, and their use cannot be sustained. The valorization of dredged sediments and recycled concrete materials as alternative construction materials has the potential to reduce the impact of these two issues. In this context, this study aims at investigating the feasibility of using dredged sediments and recycled concrete aggregates as alternative raw material for road subgrade construction. Various mix designs were prepared using dredged sediments and recycled concrete aggregates. The mixes were then treated with quicklime and road binder as specified in the French soil treatment guide. Their physical, mechanical, and geotechnical properties confirmed the feasibility of using recycled concrete aggregates and dredged sediments up to a certain percentage in road subgrade construction. Moreover, they showed that the mixes containing 20% of dredged sediments met road subgrade minimum physical and mechanical properties, such as immediate bearing capacity, unconfined compression strength, indirect tensile strength greater, and UCSI/UCS60 ratio. Finally, leaching tests were conducted to ensure the environmental safety of the various mixes. The results showed that the mixes met the thresholds for their use in road subgrade construction. The feasibility of using dredged sediments and recycled concrete aggregates in foundations and base layers will be studied in future projects.

Partial cement replacement by low-carbon-impact additions has the potential to reduce CO2 emissions. The aim of this study is the development of a ternary binder that includes ordinary Portland cement (OPC), ground granulated blast furnace slag (GGBS), and flash-calcined sediment (FCS). To upgrade dredged mineral material into FCS, a new heat treatment, i.e., flash calcination, was used. The used materials were physically, chemically, and mineralogically characterized. The mixture design method was used to optimize the design of the ternary blended binders. A model was developed and validated for the prediction of the 90-day compressive strength for mortars composed of OPC (C), GGBS (S), and FCS (F). Five mixes, reference RM (100% OPC), binary mix (50% OPC and 50% GGBS), and three ternary mixes with FCS rates of 10%, 15%, and 20% were characterized in fresh and hardened states. The results show that the incorporation of FCS reduced the workability of the mixes and increased their densities. Moreover, the initial setting time of the mix was delayed, and the heat of the hydration peak was decreased. The 90-day compressive strengths of the mix containing 10% FCS were higher than those of RM. In conclusion, the use of 10% FCS and 40% GGBS was an efficient substitute for 50% OPC.

Recent literature has exhibited a growing interest in the utilization of ground glass powder (GP) as a supplementary cementitious material (SCM). Yet, the application of SCMs in stabilizing heavy metallic and metalloid elements remains underexplored. This research zeroes in on zinc stabilization using a binder amalgam of GP and ordinary Portland cement (OPC). This study juxtaposes the stability of zinc in a recomposed binder consisting of 30% GP and 70% OPC (denoted as 30GP-M) against a reference binder of 100% CEM I 52.5 N (labeled reference mortar, RM) across curing intervals of 1, 28, and 90 days. Remarkably, the findings indicate a heightened kinetic immobilization of Zn at 90 days in the presence of GP—surging up to 40% in contrast to RM. Advanced microstructural analyses delineate the stabilization locales for Zn, including on the periphery of hydrated C3S particles (Zn–C3S), within GP-reactive sites (Si*–O–Zn), and amid C–S–H gel structures, i.e., (C/Zn)–S–H. A matrix with 30% GP bolsters the hydration process of C3S vis-à-vis the RM matrix. Probing deeper, the microstructural characterization underscores GP's prowess in Zn immobilization, particularly at the interaction zone with the paste. In the Zn milieu, it was discerning a transmutation—some products born from the GP–Portlandite reaction morph into GP–calcium–zincate. [ABSTRACT FROM AUTHOR]