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The effect of dosage of recycled aggregate from construction waste on the mechanical strength of cement stabilized macadam (CSM) was investigated, the optimal dosage and proportion of recycled aggregate were proposed based on the principle of the highest strength or the maximum dosage. The growth law of mechanical strength of cement stabilized macadam recycled aggregate ( CSMRA) was investigated under the optimal dosage, a prediction model of mechanical strength of CSMRA was proposed, and the reliability of prediction was verified. The results show that the compressive strength of CSMRA increases and then decreases with the increase of recycled fine aggregate dosage, decreases with the increase of recycled coarse aggregate dosage, and the maximum dosage of recycled aggregate is 70% (mass fraction). The correlation coefficient of established mechanical strength growth equation and prediction model is more than 0. 98, and the error between predicted value and measured value is no more than 14. 0%. This indicates that the model can accurately predict the mechanical strength of CSMRA at other ages after determining cement dosage, aggregate type, mineral proportion and 7 d strength. [ABSTRACT FROM AUTHOR]

The construction sector is among the most polluting industries globally, accounting for approximately 37.5% of the European Union's total waste generation in 2020. Therefore, it is imperative to develop strategies to enhance the sustainability of this sector. This paper proposes a multiscale COMSOL Multiphysics numerical model for an ex situ mineral carbonation process of hydrated lime. The carbonation process is characterized at both the micro- and macroscale levels, encompassing interactions within and between the particles. This model incorporates both reaction and diffusion phenomena, considering the effects of porosity and liquid-water saturation parameters. Generally, liquid-water saturation enhances the reaction kinetics but not CO2 diffusion, while porosity improves CO2 diffusion throughout the granular bed. The model has been experimentally validated, showing promising results by accurately characterizing carbonation tendencies and the influence of the CO2 flow rate and the initial water-to-solid ratio on the carbonation process. The proposed mathematical model facilitates the study of various parameters, including particle radius, reactor geometry, and material porosity. This analysis is valuable for both current and future projects, as it aims to identify the most profitable configurations for the hydrated lime carbonation process. [ABSTRACT FROM AUTHOR]

Construction waste detection under complex scenarios poses significant challenges due to low detection accuracy, high computational complexity, and large parameter volume in existing models. These challenges are critical as accurate and efficient detection is essential for effective waste management in the construction industry, which is increasingly focused on sustainability and resource optimization. This paper aims to address the low accuracy of detection, high computational complexity, and large parameter volume in the models of construction waste detection under complex scenarios. For this purpose, an improved YOLOv8-based algorithm called FE-YOLO is proposed in this paper. This algorithm replaces the C2f module in the backbone with the Faster_C2f module and integrates the ECA attention mechanism into the bottleneck layer. Also, a custom multi-class construction waste dataset is created for evaluation. FE-YOLO achieves an mAP@50 of 92.7% on this dataset, up by 3% compared to YOLOv8n. Meanwhile, the parameter count and floating-point operations are scaled down by 12% and 13%, respectively. Finally, a test is conducted on a publicly available construction waste dataset. The test results demonstrate the excellent performance of this algorithm in generalization and robustness. [ABSTRACT FROM AUTHOR]

At present, construction waste recycled aggregates only partially replace natural aggregates to prepare road-based materials. This study addressed this limitation and experimentally investigated the mechanical properties of cement-stabilized macadam base materials utilizing a construction waste recycled aggregate. The feasibility of using these raw materials to prepare cement-stabilized macadam bases was established via experimental validation. Subsequently, compaction tests were conducted to ascertain the maximum dry density and optimum moisture content in the mixture. The mechanical characteristics were further examined using unconfined compressive strength tests, analyzing and discussing the influences of varying cement dosages and curing periods on the material strength. The results indicate that the properties of the recycled aggregates satisfied specification requirements, demonstrating satisfactory mechanical properties. The unconfined compressive strength with a 7-day curing period and a 5% cement content fulfilled the technical standards for expressway-grade heavy and extremely heavy traffic, while that with a 6% cement content (with an added curing agent) met these requirements after just 1 day. Additionally, the curing agent enhanced the early strength of the recycled aggregate base material. This study has broken through the technical bottleneck of low content of recycled aggregate, achieved 100% replacement of natural aggregate, and promoted the sustainable development of the industry. [ABSTRACT FROM AUTHOR]

With rapid urbanization growth, considerable amounts of construction waste are generated on an annual basis, posing significant economic and environmental challenges worldwide. Re-cycling construction waste is a sustainable way for waste disposal, leading to the necessity of meticulous planning of recycling centers. A well-designed plan for constructing recycling centers can effectively improve the recycling rate of construction waste while minimizing investment. This paper formulates a two-stage stochastic model for planning recycling centers with the objective of maximizing the recycling rate under different scenarios. This study comprehensively considers various uncertain factors, such as the amount of construction waste generated and the demand for recycled materials. A case study of Guangzhou is used for validation, which demonstrates the effectiveness of the developed model in planning recycling center construction. The comparison between the proposed model and a conventional mean value model shows the importance of accounting for uncertainties. Specifically, the derived results indicate that 7% more construction waste is recycled with the same investment in constructing recycling centers. Additionally, via a sensitivity analysis, valuable managerial insights on investing resources in recycling center construction are provided to decision makers. Ultimately, the research findings are expected to enhance the recycling rate of construction waste, thereby contributing to sustainable industry development. [ABSTRACT FROM AUTHOR]

Effective waste elimination is critical for the success of construction projects. Although several studies have focused on various aspects of construction waste, limited efforts have yet to investigate the dynamic effect of Making-Do (MD) practices on productivity, rework, defects, and material waste. From a lean construction perspective, this study aims to address MD waste using the Last Planner System (LPS) and BIM. First, the causal structure that can cause MD in construction projects was expressed in a causal loop diagram (CLD), and thematic analysis uncovered the strategies of LPS-BIM to eliminate MD identified by reviewing the literature. Secondly, twenty-five strategies from the LPS and BIM strategies to address MD using structural equation modeling (SEM) were assessed. Subsequently, a system dynamics model (SDM) for investigating LPS-BIM strategies on MD decisions in a construction project was formulated based on the underlying causal loop diagrams and the mathematical relations among the variables. Finally, the model was applied to three projects, and simulations for four LPS-BIM scenarios were carried out. The findings show that dynamic interactions among diverse production planning and control factors are critical in evaluating MD impacts on a construction project. The results demonstrate that the LPS-BIM approach resulted in an average 43.8% reduction in the tasks performed with MD, 45.3% of constraints, 66.5% of construction waste, an increasing 13.7% completion rate, and a 29.3% cost reduction, demonstrating that LPS-BIM is a more efficient solution for MD mitigation and construction planning. This study aims to guide construction planners and policymakers to better manage their production constraints by eliminating negative MD practices from their plans. [ABSTRACT FROM AUTHOR]

With the acceleration of urban development, the annual production of urban construction waste has been increasing yearly, which brings considerable challenges for urban supervision and management, and how to quickly and accurately identify construction waste is of great practical significance. In this paper, we propose a remote sensing image dust cover net construction waste recognition algorithm based on the improved U-network model to realize construction waste target recognition. The algorithm first prepares a dust cover net construction waste identification dataset using Google high-resolution remote sensing imagery as the database. Second, VGG16 is adopted as the backbone network of the U-Net model to improve the feature expression ability of the model. Finally, the Convolution Block Attention Module (CBAM) is embedded into the U-Net network to construct the CBAM-U-Net model to enhance the information extraction accuracy of high-resolution remote sensing images. With the remote sensing image encompassing Daxing District in Beijing as an example, the results show that the proposed algorithm can automatically and efficiently recognize the dust cover net construction waste with 95.51% recognition accuracy and 95.08% Mlou, which puts forward a new idea for the supervision of construction waste. [ABSTRACT FROM AUTHOR]

Abstract Background Due to growing global concerns regarding the management of construction waste, this study investigates the feasibility of creating engineered geopolymer composites by replacing traditional industrial by-products (slag) with construction waste, specifically recycled brick waste powder. Results Polyvinyl alcohol fibers were incorporated into the engineered geopolymer composite mixtures. The substitution of slag with recycled brick waste powder was carried out at varying percentages: 0, 20, 40, 60, 80, and 100%, resulting in six different engineered geopolymer composite mixtures. The study evaluated the flexural strength, sorptivity, water absorption, and abrasion resistance of the engineered geopolymer composites, and also, microstructural characterization was conducted using scanning electron microscopy. The findings demonstrated that incorporating recycled brick waste powder into the engineered geopolymer composite mixes resulted in a decrease in flexural strength by 35.59% and a notable increase in midspan deflection by 339% when slag was replaced. Concurrently, there was a significant rise in water absorption and sorptivity by approximately 304 and 214%, respectively, when slag was entirely substituted with recycled brick waste powder. Conversely, abrasion resistance decreased, with the inclusion of recycled brick waste powder resulting in an 84% increase in volume change. The scanning electron microscopy (SEM) analysis showed active geopolymerization of recycled brick waste powder within the engineered geopolymer composite mixtures. Conclusions The results of this investigation demonstrate that it is feasible to produce engineered geopolymer composites using recycled brick waste powder instead of slag. The greater ductility and increased midspan deflection point to areas that require further optimization, even in spite of the observed decreases in flexural strength and abrasion resistance. The SEM examination reveals an active geopolymerization, highlighting the potential of recycled brick waste powder to produce environmentally friendly and sustainable construction materials. These results offer a good starting point for further studies that try to maximize the durability and performance of these composites.

Extreme rainfall significantly threatens the safety of the landfill cover system, especially under humid climates. This study aims to provide design recommendations for a sustainable landfill cover system consisting of a low-permeability soil layer underlying a two-layer capillary barrier for humid climates. First, the numerical back-analysis was conducted for verification against a series of flume model tests. Then, a parametric study was performed to investigate the effects of inclination angle, particle size and layer thickness on the lateral diversion length (DL) of the three-layer cover system under the 100-year return period rainfall of humid climates. The results show that the water lateral DL of the cover system can be greatly enhanced by increasing the inclination angle from 3° to 18°. Moreover, the bottom layer of the cover system with a coarser d10 was more susceptible to the impact of the heavy rainfall, while this can be alleviated by increasing the thickness of the bottom layer. A dimensionless number, defined as the ratio of thickness and d10 of the bottom layer, is proposed for designing lateral diversion of the three-layer cover system under humid climates. To preserve the maximum DL, it is suggested that the proposed dimensionless number should be larger than 95 and 110 for the design of rainfall events with 50-year and 100-year return periods for humid climates, respectively.

Porous sound absorption ceramic is one of the most promising materials for effectively eliminating noise pollution. However, its high production cost and low mechanical strength limit its practical applications. In this work, low-cost and in situ mullite whisker-reinforced porous sound-absorbing ceramics were prepared using recyclable construction waste and Al2O3 powder as the main raw materials, and AlF3 and CeO2 as the additives, respectively. The effects of CeO2 content, AlF3 content, and sintering temperature on the microstructure and properties of the porous ceramics were systematically investigated. The results showed that a small amount of CeO2 significantly promoted the growth of elongated mullite crystals in the resultant porous ceramics, decreased the growth temperature of the mullite whiskers, and significantly increased the biaxial flexural strength. When 2 wt.% CeO2 and 12 wt.% AlF3 were added to the system, mullite whiskers were successfully obtained at a sintering temperature of 1300 °C for 1 h, which exhibited excellent properties, including an open porosity of 56.4 ± 0.6%, an average pore size of 1.32–2.54 μm, a biaxial flexural strength of 23.7 ± 0.9 MPa, and a sound absorption coefficient of >0.8 at 800–4000 Hz. [ABSTRACT FROM AUTHOR]

Background: Due to growing global concerns regarding the management of construction waste, this study investigates the feasibility of creating engineered geopolymer composites by replacing traditional industrial by-products (slag) with construction waste, specifically recycled brick waste powder. Results: Polyvinyl alcohol fibers were incorporated into the engineered geopolymer composite mixtures. The substitution of slag with recycled brick waste powder was carried out at varying percentages: 0, 20, 40, 60, 80, and 100%, resulting in six different engineered geopolymer composite mixtures. The study evaluated the flexural strength, sorptivity, water absorption, and abrasion resistance of the engineered geopolymer composites, and also, microstructural characterization was conducted using scanning electron microscopy. The findings demonstrated that incorporating recycled brick waste powder into the engineered geopolymer composite mixes resulted in a decrease in flexural strength by 35.59% and a notable increase in midspan deflection by 339% when slag was replaced. Concurrently, there was a significant rise in water absorption and sorptivity by approximately 304 and 214%, respectively, when slag was entirely substituted with recycled brick waste powder. Conversely, abrasion resistance decreased, with the inclusion of recycled brick waste powder resulting in an 84% increase in volume change. The scanning electron microscopy (SEM) analysis showed active geopolymerization of recycled brick waste powder within the engineered geopolymer composite mixtures. Conclusions: The results of this investigation demonstrate that it is feasible to produce engineered geopolymer composites using recycled brick waste powder instead of slag. The greater ductility and increased midspan deflection point to areas that require further optimization, even in spite of the observed decreases in flexural strength and abrasion resistance. The SEM examination reveals an active geopolymerization, highlighting the potential of recycled brick waste powder to produce environmentally friendly and sustainable construction materials. These results offer a good starting point for further studies that try to maximize the durability and performance of these composites. [ABSTRACT FROM AUTHOR]

With the rapid pace of global urbanisation, construction demolition waste (CDW) constitutes roughly 36% of the total solid waste deposited in landfill sites worldwide, thereby posing a significant challenge to the sustainability of the construction industry. To address this issue, circular economy strategies are proposed as a solution. This paper systematically analyses 55 research articles published in leading peer-reviewed English-language scholarly journals over the past decade. It aims to identify and categorise drivers for enhanced CDW management by synthesising findings from previous research to support the principles of a circular economy. Utilising a PESTLE model for classification and analysis provides valuable insights into disparities and distinctions among categories, regions, and countries. The resulting analysis yields valuable insights into enablers and trends, with the aim of making a substantial contribution to mitigating the impact of construction activities and thus fostering the establishment of an efficient circular economy within the sector. [ABSTRACT FROM AUTHOR]

Civil construction is one of the oldest activities known to humanity, with reports indicating that builders from the Roman Empire were already seeking to reuse materials. Currently, considering the depletion of natural resource supplies, the recycling of solid construction and demolition waste (CDW) not only provides new products but also presents ecological and economical alternatives. In this context, this research explores new variables for the disposal of CDW, with the manufacturing of artificial finishing stones appearing as a strong possibility to be studied. This research presents the development of a new composite from CDW, using an orthophthalic polyester resin as a binder. The waste was sieved and separated by granulometry using the simplex centroid method. The best-compacted mixture was determined statistically by ANOVA and Tukey's test. The waste was characterized by X-ray fluorescence, and the resin by Fourier transform infrared spectroscopy. Artificial stone slabs were produced with 85% waste and 15% resin by mass, using the vibro-compression and vacuum system. They were subsequently cut for mechanical, physical, and chemical tests. Microstructural analysis was performed using scanning electron microscopy on the surfaces of the fractured compositions, as well as on the grains. The artificial stone with the best results had a density of 2.256 g/cm3, a water absorption of 0.69%, and an apparent porosity of 1.55%. It also exhibited a flexural strength of 34.74 MPa and a compressive strength of 111.96 MPa, alongside good results in alterability and thermal tests. In this satisfactory scenario, the use of this waste in the composition of artificial stones is promising, as it directly aligns with the concept of sustainable development. It replaces the end-of-life concept of the linear economy with new circular flows of reuse, restoration, and renewal, in an integrated process of the circular economy. Additionally, the quality of the final product exhibits properties similar to those of commercially available artificial stones. [ABSTRACT FROM AUTHOR]

Construction waste causes severe environmental problems. Reducing construction waste generation becomes a major policy measure of governments to achieve sustainable development. Offsite construction approaches are effective for reducing onsite construction waste. Nevertheless, there is a lack of a clear understanding of the types and amounts of construction waste that different offsite construction approaches can reduce. This study aims to investigate the performance of the modular construction (MC) approach in construction waste generation and reduction and how it differs from that of the nonmodular offsite construction (NMOC) approaches by comparing 59 selected cases of building projects that adopt these offsite approaches compared with stick-built construction. Results indicated that the adoption of offsite construction contributed to significant onsite construction waste reduction. On average, adopting MC reduced 78.8% of overall construction waste, outperforming other construction approaches. The level of prefabrication influenced onsite construction waste generation and reduction the most, followed by the other properties like building typology, density, and material used. Seven knowledge gaps were identified in the area of waste identification, quantification, and assessment. The findings demonstrate the advantages of using offsite construction in waste control and management and add to the existing body of knowledge on onsite construction waste generation and on waste reduction through adopting MC. The identified knowledge gaps point directions of future research on waste reduction through offsite construction. Practical Applications: The results of this paper suggest that the adoption of offsite construction can contribute to significant onsite construction waste reductions compared with conventional stick-built construction. Specifically, buildings adopting the modular construction (MC) approach can reduce overall construction wastes by around 80% and outperform other nonmodular offsite construction approaches, including those that adopt one-dimensional prefabricated beams and columns, two-dimensional prefabricated panels, or three-dimensional prefabricated pods, based on the analysis of 59 building cases covering different levels of prefabrication, building typologies, building densities, and building materials. This study contributes to the investigation of onsite construction waste by proposing a systematic assessment method addressing different construction waste types and assessment criteria. It facilitates a better understanding of the advantages of offsite construction in terms of waste control and management, especially MC, which was underexplored in the literature. Seven knowledge gaps were identified in the area of construction waste identification, quantification, and assessment. Addressing these knowledge gaps will contribute to better construction waste control and management, especially in MC projects. [ABSTRACT FROM AUTHOR]

With the rapid development of the construction industry, construction waste (CW) has recently attracted much attention in many developing countries such as Türkiye. As a result, the effective management of construction waste has emerged as a critical concern at the global level. Reducing and managing CW is imperative to promote sustainable urban development. Although several scholars have made many valuable attempts to develop strategies to minimize CW, one of the most effective ways is to propose a road map for CW minimization, which is a method that has never been applied before, neither in this domain nor in the construction management and architectural domain. Unlike former studies, a roadmap was developed for reducing CW in this study. To create a roadmap, three steps were followed in this study. Firstly, CW causes were identified with a systematic literature review. Then, surveys were conducted with the construction stakeholders to obtain their perceptions of these causes. A normalized mean value analysis was conducted, and the importance and criticality of the CW causes were determined. Secondly, a timeline was developed, and it overlapped with the importance of the causes. Finally, roadmap strategies were created, and solutions were proposed to solve the causes of CW in the short, medium, and long term. The roadmap method, which is often used to develop new technologies, has not been used in this way to solve a problem before. Therefore, the study is unique and offers strategies that can be integrated into other studies. [ABSTRACT FROM AUTHOR]

The urbanization process generates a substantial amount of construction waste, and traditional disposal methods lead to environmental pollution and resource wastage. There is an urgent need to develop more efficient and environmentally friendly treatment technologies. This paper investigates the pyrolysis characteristics of construction waste and its application in low-temperature thermal cycle systems. First, the pyrolysis reaction mechanism of construction waste is analyzed through experiments and simulations, revealing the decomposition patterns and reaction mechanisms of various components during pyrolysis. Secondly, the thermodynamic performance of construction waste in lowtemperature thermal cycle systems is evaluated to explore its feasibility and application prospects in practical engineering. The research results indicate that the pyrolysis of construction waste can effectively reduce waste volume and produce high-value-added products. The low-temperature thermal cycle system shows promising potential in terms of energy utilization efficiency and economic viability. This study provides a theoretical foundation for the treatment and resource utilization of construction waste and is significant for promoting green building and sustainable development. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization, the volume of construction waste has increased rapidly, posing a challenge in effective utilization. Heat pump systems, known for their energy efficiency and environmental benefits, offer a promising solution by using construction waste as a low-temperature heat source. This not only mitigates the pollution caused by waste but also facilitates the efficient recycling and reuse of resources. While existing studies have mainly focused on performance evaluation of heat pump systems, research on using construction waste as a heat source is relatively sparse. Exploring this innovative heat source application could provide new directions for the development of heat pump technology. Despite achievements in performance evaluation and waste utilization, there are shortcomings such as a strong dependence on traditional heat sources, insufficient consideration of the unique properties of construction waste, and imperfect analysis methods for component exergy losses. This paper is divided into two main sections: the construction of a mathematical model for a heat pump system using construction waste as a low-temperature heat source, explaining the underlying principles; and a detailed analysis of the exergy losses in system components, proposing a method for performance evaluation. Through this research, the paper aims to provide new technical support for the recycling of construction waste, enhance the overall efficiency of heat pump systems, and advance the development of energy-saving and environmental technologies. [ABSTRACT FROM AUTHOR]

Construction waste with more fine particle occupies the amount of land and the utilization rate is low. Using fine-particle construction waste to fill mining gob is an effective way to release land resources and to slow down surface subsidence in mine area. The permeability of filling body is the key factor to affect the geological environment and regional hydrological cycle of filling gob. The paper analyzed respectively the components of fine particle and large-size particle of construction waste by the diffraction analysis, explored the formation mechanism of seepage pore in construction waste samples containing more fine particle, characterized quantitatively the porosity and seepage path of the samples by Matlab binaryzation and mass fractal dimension respectively, established the pore-fractal-permeability model of construction waste filling samples containing more fine particle, and verified the model by experiment. The study showed that the permeability weakened with the increase of < 2 mm particle (fine-particle) content. Permeability coefficient of the samples containing 15% cement was less than that of non-cemented one when fine-particle content was less than 26.09%, vice versa in fine-particle content more than 26.09% because ineffective pores among the fine-particle samples gathered into regular oval effective pores under cement bonding. Both cementation and permeation reduced the effective porosity of the samples, while their influence was different when they worked together. The influence of permeation on the effective porosity of the samples was greater than that of cementation when fine content was 21.38–46.51%, vice versa in fine content less than 21.38% or more than 46.51%. The effective porosity of the permeable cemented samples was less than the one of the impermeable non-cemented samples in fine content 26.09–46.51%, vice versa in fine content 21.38–26.09%. The Matlab binary of sample images could well characterize the porosity, and the mass fractal dimension could describe the permeation path characteristics in the samples. And the theoretical calculation of the model was in accord with the experimental results. [ABSTRACT FROM AUTHOR]

The aim of this article was to conduct a spatial and territorial analysis of the urban mining potential of the European Metropolis of Lille (MEL), which had 1,174,273 inhabitants in 2018. This involved quantifying construction and demolition waste (CDW) deposits and analyzing their spatial distribution. The chosen quantification approach utilized building and demolition permits as input data, along with waste diagnostics for Construction and Building Materials Products (CBMPs) obtained from stakeholders in the building sector. Waste quantities were estimated using the production rate calculation method (GRC). Specifically, the calculation based on surface area combined with GIS geographic information systems. CDW quantities were categorized by demolition rehabilitation and construction; by type (hazardous non-hazardous inert); and by urban fabric. For the MEL area, the findings revealed that building sites covered the largest surface area, with over 8 million m² being constructed between 2013 and 2022. The construction activity, including renovation, is expected to constitute approximately 20% of the MEL's building stock from 2013 to 2022. During the same period, 5.51% of the MEL's building stock was demolished. This corresponds to nearly 6 million tons of CDW being generated during this period, averaging 661318 tons per year. Demolition sites contributed 73% of the total CDW production, compared to 22% for new construction and 4% for renovation sites. Inert waste continued to dominate the composition of waste, accounting for 90% of the total with 9% for non-hazardous waste and 1% for hazardous waste. Semi-detached and grouped houses business fabrics and townhouses or collective fabrics were identified as the primary type of waste-producing urban fabrics. Furthermore, our GIS-based methodology enabled the analysis of CDW quantity distribution by municipality, providing essential data for understanding the urban mining potential and the disparity between construction material requirements for new buildings and resources derived from building demolition. This approach facilitates the assessment of (1) a geographical area's reliance on construction materials, and (2) the significance of reusing and recycling products equipment materials and waste (PEMW) in new construction to achieve circular economy objectives and to comply with the Extended Producer Responsibility (EPR) channel initiated in France in 2023. Over the period from 2013 to 2022, annual construction material requirements remained significantly higher than resources from building demolition and rehabilitation, ranging between 29% and 35%. Additionally, the analysis indicated a potential 41% rate of substitution of new construction materials with secondary primary materials in the MEL, varying by municipality and typology, with higher rates in rural communities and lower rates in urban communities. [ABSTRACT FROM AUTHOR]

The purpose of the research described in this article was to optimize the compositions based on hydraulic-modified binder and construction waste for waterproofing and repair of concrete or brick structures in contact with the ground, as well as the study of properties and development of the basis of the methodology for selecting the composition of such a waterproofing system. Processing of the results of the experiment was carried out by statistical and analytical methods. The research was based on a method for determining the adhesive strength of a waterproofing coating, based on the determination when the insulating layers are torn off. As a result of the calculation and experimental verification, the composition of the waterproofing material was obtained, which corresponds to an adhesive strength of 3.8 MPa; the strength of the waterproofing layer was 36–37 MPa, as well as the amounts of the main components: acrylic resin 3.9%; finely ground concrete waste 80 kg/m3; plasticizer consumption (0.38...0.39%) at the optimum moisture content of the base surface (9.7...9.8%). [ABSTRACT FROM AUTHOR]

The construction sector of Pakistan is on a cross-growth trajectory, developing under the twin pressures of emerging infrastructure-based demands and sustainable practices that need to be inculcated urgently. This article focuses on the critical evaluation of sustainable waste management practices within the fast-developing construction industry of Pakistan, and clearly delineates a research gap in the current methodologies and use of data combined with the absence of a strategy for effective management of concrete waste. This research aims to utilize an algorithm based on machine learning that will provide accurate prediction in the generation of construction waste by harnessing the potential of real-time data for improved sustainability in the construction process. This research has identified fundamental factors leading systematically to the generation of concrete waste by creating an extensive dataset from construction firms all over Pakistan. This research study also identifies the potential concrete causes and proposed strategies towards the minimization of waste with a strong focus on the reuse and recycling of the same concrete material to enhance the adoption of sustainable practices. The prediction of the model indicates that the volumes of construction are to increase to 158 cubic meters by 2030 and 192 cubic meters by 2040. Further, it projects the increase in concrete construction waste volumes to 223 cubic meters by the year 2050 through historical wastage patterns. [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Usually, aggregates used for asphalt mixtures consist mainly of natural aggregates. Sometimes the natural aggregates are substituted with limited amounts of industrial and construction wastes. The current paper deals with evaluating the mechanical performance of new developed hot asphalt mixtures made of up to 98% industrial and construction by products. In this project, different types of industrial by-products, namely, RAP, foundry sand, and steel slag in addition to biobased rejuvenators have been used to find the composition of the best asphalt mixtures made mainly of wastes that can substitute the asphalt mixtures made of natural aggregates. Fourteen selected asphalt mixtures have been evaluated using the circular road simulator test at VTI. The CRS testing program has been set up to allow different measurements, e.g. surface deterioration and wear, friction, and visual inspection. The test results demonstrated that it is possible to obtain paving mixtures with high content of recycled materials. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Construction and demolition waste (CDW) was fully exploited to prepare high-strength and low-cost unfired bricks. A compound additive consisting of sodium silicate, microsilica powder, an early-strength water reducer, and wood fiber was incorporated into the bricks. Tests (compressive tests, freeze--thaw cycle tests, and scanning electron microscopy (SEM)) were carried out to determine the effect of the contents of the additive components on the properties (the strength, softening coefficient, freezing resistance, hydration products, and microscopic morphology) of unfired bricks of different curing ages. The experimental results were used to determine the optimum ratio of the components and the hydration mechanism. The optimized compound additive considerably improved the mechanical properties and crack resistance of the bricks, where the optimum content was found to be only 3.15% of the CDW dry mass. Compared with unfired bricks with no additives, unfired bricks with the optimized compound additive exhibited increases in the 1- and 28-day compressive strengths and softening coefficient of up to 66.8%, 65.9%, and 8.46%, respectively (corresponding to values of 8.46 MPa, 29.36 MPa, and 0.934, respectively) and a decrease in the freeze--thaw strength loss rate of 61.38%. Incorporating the compound additive into the unfired bricks considerably reduced the environmental impact. The SEM micrographs showed that the compound additive increased the silicon-to-calcium ratio and workability of the preparation mixture, increased the hydration rate, promoted the conversion of calcium hydroxide in the product to a C--S--H gel, and enhanced the density and strength of the hydration product. [ABSTRACT FROM AUTHOR]

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With the advancement of urbanization construction, the proportion of construction waste to the total urban waste continues to increase, especially waste concrete. The treatment and reuse of waste concrete is a major trend that poses enormous pressure on environmental protection. This article focuses on the problems in the preparation of recycled aggregates from waste concrete, which has important practical value. This article presents a new type of recycled concrete prepared through surface modification of recycled coarse aggregate and design experiments to change the replacement rate of coarse aggregate. The physical properties of recycled coarse aggregate, workability of fresh concrete, and mechanical properties of recycled concrete are analyzed. The research results indicate the following: (1) Through surface modification, recycled concrete can improve the workability of fresh concrete at a fixed water cement ratio, which can meet the requirements of mixing, transportation, and pouring of fresh concrete. (2) By modifying the surface of recycled aggregates, the strong water absorption performance of recycled aggregates caused by old mortar and surface defects has been reduced. And the modification effect of recycled aggregate improves the hydration process of recycled concrete, making the surface structure dense and further enhancing the strength of recycled concrete. (3) The compressive strength of recycled concrete specifications from construction waste shows a decreasing trend with the increase in coat aggregate replacement rate. The final ratio is as follows: modular dose of 12%, modification time of 90 min, and 20% recycled aggregate content. [ABSTRACT FROM AUTHOR]

Construction waste is a global problem, including in New Zealand where it makes up 40–50% of landfill waste. Accurately measuring construction waste is crucial to reduce its impact on New Zealand's landfills and meet carbon targets. Waste can be effectively managed if predicted correctly from the start of a project. Waste generation depends on factors such as geography, society, technology, and construction methods. This study focuses on developing a model specific to New Zealand to predict waste generation in residential buildings. By analysing data from 213 residential projects, the study identifies the design features that have the greatest influence on construction waste generation. A generalized linear model is constructed to correlate these design features with waste generation. The findings are valuable for construction stakeholders seeking to implement waste reduction strategies based on predicted waste quantities. This research serves as a starting point, and further investigation in this area is necessary. [ABSTRACT FROM AUTHOR]

The rapid development of urbanization and large-scale engineering projects have led to the output of a large quantity of construction waste, which also puts great pressure on the environment. Environmental efficiency, as one of the criteria for measuring sustainable development, can be used to measure the impact of enterprises, industries, or regions on the environment when creating economic value. This research takes 30 provinces in China as samples and uses configuration analysis and fuzzy-set qualitative comparative analysis (fsQCA) methods to analyze the combined effects of factors affecting the environmental efficiency of construction waste generation, to find upgrading paths to improve environmental efficiency. The results indicate that five configurations can promote provinces to achieve high environmental efficiency, which can be classified into three types: population density, technological innovation, and policy economy. These three configurations reveal the comprehensive impact of systematic correlations among population, technology, policy, and economic factors on environmental efficiency improvements. This research provides a certain theoretical reference for exploring the influencing factors of environmental efficiency and provides theoretical guidance for selecting different paths to improve the environmental efficiency of construction waste in regions with different social conditions. [ABSTRACT FROM AUTHOR]

C&DW is contributing to exceeding all planetary boundaries and presents a range of other issues. In order to better understand the existing research on C&DW, a global bibliographic analysis was undertaken through seven groups of keyword searches of Scopus and the results visualised using VOSviewer. The study identifies phases in discussion of C&DW in terms of volume and themes and examines how search terms influence what is found. The results show that C&DW receives only a modest research attention compared to other areas of waste, and this is despite an exponential increase in C&DW research since 2016. The analyses also show that concrete is the most researched material in terms of C&DW, and that reuse, recycling, and circular economy are so far attracting only proportionally modest research attention. This signals a need for further acceleration of the C&DW research, and specifically for more research on reuse, recycling, and circular economy for materials other than concrete. One important finding are differences observed when using different search terms related to C&DW, which suggests that single search studies might provide limited insights. [ABSTRACT FROM AUTHOR]

According to the technical requirements and limiting factors of a certain project, research on the land reclamation technology of construction waste was carried out. Based on the analysis of the material characteristics of construction waste, two-stage screening facility with a three-step and low-friction grizzle type vibrating feeder with screening function and snap type vibrating screen with adjustable amplitude were proposed to solve the difficulty of screening qualified material from construction waste. The self-propelled flat barge with on-board excavators has been developed to achieve shipping, unloading and transferring construction waste to other barges. A new type of environmental protection split barge with shallow draft, low headroom and adjustable anti-pollution curtain has been developed for the environmental backfilling under sea surface under the height and depth limit conditions. [ABSTRACT FROM AUTHOR]

Low-energy asphalt techniques, such as warm mix asphalt (WMA), combined with the rational consumption of geomaterials and waste recycling would promote more sustainable and energy-efficient asphalt pavements. In volcanic environments, a significant proportion of aggregate production is discarded due to its extreme porosity, and used tires generate a main environmental issue as well. While recycled rubber powder from tire waste can enhance the mechanical behavior of asphalt, it also raises its viscosity. Therefore, joining rubberized asphalt containing local waste geomaterials with WMA technologies is crucial to reduce the manufacturing temperatures and emissions and to produce more eco-efficient pavements. For this purpose, the most relevant technological characteristics of rubberized warm mix asphalt with residual aggregates from highly vesiculated volcanic rocks are tested in the laboratory and contrasted with conventional mixtures. The outcomes demonstrate not only the feasibility of the production of such mixtures in line with the current specifications, but also show a significant improvement in the resistance to moisture and to plastic deformations, and an improvement in the stiffness modulus. The eco-efficiency indicators conclude that the energy consumption and emissions are reduced by 9%, enabling the reuse of waste materials by more than 95%. [ABSTRACT FROM AUTHOR]

This paper aimed to investigate the possibility of using alkaline-based binders made from the industrial waste produced by ceramic tiles in the field of conservation and the restoration of monuments and archaeological heritage. Geopolymer mortars, which are environmentally sustainable products obtained by chemical consolidation at room temperature, are studied for their versatility in applications as reintegration or bedding mortars and pre-cast elements, namely bricks, tiles or missing parts for archaeological pottery, as an alternative to traditional not sustainable products. Starting from a well-established formulation, the function of the product, meaning its technical characteristics and its workability, was optimized by changing the aggregates used, by adding a Ca-rich compound or by changing the liquid/solid ratio with the use of tap water. The possibility of tailoring the finishing of the obtained products was also evaluated. X-ray diffraction analysis showed the influence of adding the additive with the presence of newly formed phases, which positively affect the product's workability. On the contrary, no important variations were observed with the increase in the water content of the same formulation, opening up the possibility of managing it according to the required fluidity of the final product. Good results were observed, jumping above the laboratory scale and overcoming criticalities linked to the variabilities on site and the higher volume of materials used for industrial processes. The present research also demonstrates that ceramic-based geopolymers are suitable for application in a large variety of cultural heritage projects and with different purposes. Therefore, the paper encourages the use of alkali-activated mortars for green restoration, specifically given the wide range of ceramic materials. [ABSTRACT FROM AUTHOR]

The construction industry plays a vital role in the economic development of any country. Concurrently, the sector also generates enormous quantities of construction and demolition waste (CDW) that damages the ecology causing environmental pollution and deteriorating human health. Recently, various governments and other organizations realized the importance of implementing construction waste management (CWM) practices to attain sustainability in construction. The current decade can be called a pathway for achieving the 2030 agenda for sustainable development goals in which CWM plays an inevitable role. However, accurately quantifying construction waste is necessary to successfully implement any CDW management plan. A detailed literature review for the current research revealed that limited information on the magnitude of construction waste is available in India. Therefore, the current paper proposes a practically viable model to estimate the waste generation index (construction waste generated per total floor area) of high-rise residential buildings in India. The waste quantification is being done based on the project documents and expert interviews. The methodology is later validated through a high-rise building with G + 18 stories located in Kerala, India. The study indicated that a high-rise concrete framed structure generates 122.3 kg m−2 of waste during construction. It was also noted that, concrete, aggregates and blocks constitute 92% of the total waste generated in the project. The developed model can also be used as a cornerstone for establishing a construction waste database at the regional level. [ABSTRACT FROM AUTHOR]