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This research is focused on the development of an eco-friendly low-cost concrete using fly ash (FA) and marble powder waste (MPW) as partial replacements for cement and fine aggregate respectively. The substantial use of cement in concrete makes it expensive and contributes to global warming due to high carbon emissions. Thus, using such waste materials can help reduce the overall carbon footprint. For this purpose, various mix designs of concrete were developed by varying the percentages of FA and MPW. The concrete's fresh and hardened properties were experimentally determined for those mixes. The test results revealed that MPW as a sand substitute increases strength up to 40% and gradually decreases beyond that, but a 60% replacement still has more strength than the control specimen. Similarly, using FA as a cement replacement was found to reduce the strength, but the reduction was not very significant up to 20%. A mixed blend of FA and MPW showed superior results and maximum strength was obtained at F10M40. The optimal mix, with 10% FA and 40% MPW (F10M40), achieved a compressive strength of 4493.46 psi, a 16.21% improvement compared to the control mix proportion. Furthermore, the microstructure of the cementitious material was improved due to the pozzolanic reaction that led to a denser microstructure, as supported by the permeability test and SEM analysis.

In this experimental research, limestone waste powder and marble based coarse aggregate were practised for the upgradation of the concrete. Limestone waste powder was applied at 3%, 6%, 9%, 12%, 15%, 18% and 21% in alternative to the regular binder and marble based coarse aggregate was applied at 10%, 20%, 30%, 40%, 50%, 60% and 70% in alternative to the regular gravel. So as to check the output of application of new constituents, some major examinations were executed over the prepared samples. M-40 grade of concrete was taken into account for the preparation of entire mix. 0.45 water to binder proportion was taken for the modification of the entire mix. The examination outcomes revealed that with the intensification in the proportion of the limestone waste powder, intensification in the resistance against the compressive loads has been observes. Also, the maximum resistance against the compressive loads was originated at 18% utilization of limestone waste powder. The examination outcomes also revealed that with the intensification in the proportion of the marble waste aggregate, intensification in the resistance against the compressive loads has been observed. Also, the maximum resistance against the compressive loads was originated at 60% utilization of marble waste aggregate. Also, the maximum resistance against the flexural loads was originated at 18% utilization of limestone waste powder. The examination outcomes also revealed that with the intensification in the proportion of the marble waste aggregate, intensification in the resistance against the flexural loads has been observed. Also, the maximum resistance against the flexural loads was originated at 60% utilization of marble waste aggregate.

Soil stabilization is a critical step in numerous engineering projects, preventing soil erosion, increasing soil strength, and reducing the risk of subsidence. Due to its inexpensive cost and potential environmental benefits, waste materials, such as waste marble powder (WMP), have been used as additives for soil stabilization in recent years. This study investigates waste marble powder’s effects on unconfined compressive strength (UCS) and clayey soil’s ultrasonic pulse velocity (UPV) at different water contents and curing times, and artificial neural networks (ANNs) are also used to predict the UCS and UPV values based on three input variables (percentage of waste marble dust, curing time, and moisture content). Geo-engineering experiments (Atterberg limits, compaction characteristics, specific gravity, UCS, and UPV) and analytical methods (ANNs) are used. The study results indicate that the soil is high-plasticity clay (CH) using the Unified Soil Classification System (USCS), and adding waste marble powder (WMP) can significantly improve the UCS and UPV of clay soils, especially at optimal water content, curing times of 28 days, and 60% WMP. It is found that the ANN models accurately predict the UCS and UPV values with high correlation coefficients approaching 1. In addition, this study shows that the optimum water content and curing time for stabilized clay soils depend on the grade and amount of waste marble powder utilized. Overall, the study demonstrates the potential of waste marble dust as a soil stabilization additive and the usefulness of ANNs in predicting UCS and UPV values. This study’s results are relevant to engineers and researchers working on soil stabilization projects, such as foundations and backfills. They can contribute to the development of sustainable and cost-effective soil stabilization solutions.

The growing demand for cement in construction contributes significantly to environmental degradation due to its high energy consumption and carbon emissions. As a result, there is a pressing need for sustainable alternatives to reduce the environmental footprint of cement production. This study explores the use of marble and glass waste powders as supplementary cementitious materials in mortar production to reduce the environmental impact of cement. By partially replacing cement with varying percentages (0–30%) of marble and glass waste powders, the research evaluates their effects on workability, mechanical properties (compressive strength, density, ultrasonic pulse velocity), and durability (sulfate attack, water absorption, porosity). The results show that a 10% replacement of cement with marble and glass waste powder (MGWP) enhances compressive strength by 25.6% at 28 days and 17.26% at 56 days while improving microstructure and durability through compacted morphology and secondary C-S-H formation. The findings suggest that using MGWP up to 10% is optimal for enhancing the performance of mortar, providing a sustainable alternative to traditional cement with practical implications for greener construction practices.

Egypt’s thriving marble industry produces extensive waste marble powder (WMP) amounts. Recycling plentiful waste safely and effectively is a key national concern, as improper disposal poses a serious threat to the environment. This study addressed this challenge by exploring a new method to produce CaO from WMP by appropriate calcination (CWMP), which can be used as an effective additive for alkali-activated slag (AAS) cement. The CaO extracted from WMP (CWMP) was introduced into AAS cement at varying levels, ranging from 2.5 up to 15%, in 2.5% increments, by weight, as a partial slag replacement. Multiple assessments were conducted to evaluate the influence of CWMP (i.e., CaO derivative from WMP) on specific features of AAS cement. Superior analytical techniques were utilized to achieve a deeper comprehension of the results. The findings revealed a decrease in both flowability and setting time with including CWMP. As the CWMP amount increased, flowability decreased, and setting time became shorter. The introduction of CWMP up to 10% improved performance, with the optimal at 7.5%, improving compressive strength and the ability to withstand environmental conditions. Specifically, the optimal 7.5% CWMP addition increased the 28-day compressive strength by 22.96% and reduced the strength loss after durability cycling from 14.43 to 10.93%. Additionally, the persistent issue of drying shrinkage within this system could also be alleviated by including CWMP up to 10%, particularly at 7.5%. Amounts of CWMP over 10% showed detrimental effects. Repurposing WMP as a CaO source not only manages a problematic waste stream but also saves CaO produced from natural limestone.

Currently, the costs of building materials, especially cement, are increasing. Waste marble powder (WMP) could be used as a cement replacement material to produce environmentally friendly concrete to help preserve resources and reduce environmental pollution. The study’s goals are (1) to evaluate the effects of using marble powder in place of cement in high-strength concrete (HSC) on the material’s mechanical properties and durability characteristics. (2) The study is expanded to assess the effect of using partial WMP on the shear behavior of HSC beams under static loads. Eight half-scale simply supported reinforced beams with and without WMP have been tested. Each beam’s cross-section was 120 × 200 mm, and each beam had a total length of 1000 mm. The ratios of the used WMP were 0%, 2.5%, 5%, 7.5% by weight, and two different stirrup ratios, 0% and 0.47%, were used. When applied to HSC beams with and without WMP, the shear strength provisions of two of the most used codes, such as the locally used Egyptian Code (ECP 207) and the internationally used American Concrete Institute’s (ACI-2019), were examined. Using the ABAQUS software, the experimental results were compared to the findings of the nonlinear finite element analysis. The results established that partial replacement of cement by WMP led to increases in the concrete’s compressive and tensile strengths of about 15% and 16%, respectively. When tested specimens were exposed to acid attack, there were slight losses in weight and compressive strength (1.25% to 2.47%) for both with and without the addition of WMP. Both the concrete with and without WMP showed the same level of water absorption. Additionally, WMP led to an enhancement in the shear capacities for all beams. Increasing the WMP ratio from 0% to 2.5%, 5%, and 7.5% increased the shear capacity by about 13%, 20%, and 28%, respectively, for beams without stirrups, while for beams with stirrups, the shear capacity improved by 12%, 19%, and 25%, respectively. The enhancement in the beams’ shear capacities could be attributed to the advanced concrete matrix produced by WMP’s extremely small particle size.

Marble production and processing generates a large amount of marble powder waste that has great potential for cementitious material. This paper investigates the application of waste marble powder with different replacement ratios of cement in concrete and experimentally studies the physical and mechanical properties of this green concrete type. Artificial marble powder and original marble powder are used at different replacement levels. The effect of different kinds of marble powder and its replacement ratio on the mechanical properties of concrete are discussed. The results show that the compressive strength, splitting tensile strength, and flexural strength change significantly when the substitution rate of marble powder exceeds 10%; the strength decreases as the substitution rate increases. The usage of artificial marble powder plays a weakening role on concrete performance due to its resin composition when compared to the performance using original marble powder. The stress–stain curves of the two types of marble powder concrete are compared. For concrete, by using the original marble powder, the variation of strain value is not obvious when the marble powder replacement ratio is less than 20%, but for concrete by using artificial marble powder, the peak and ultimate strain decrease significantly with the replacement ratio of marble powder increase.

Waste marble powder (WMP) is a rich source of calcium and magnesium salts having an affinity for fluoride ions and therefore serves as a good defluoridation agent. Hydroxyapatite was synthesized from WMP generated by the marble processing industry to make an adsorbent for drinking water defluoridation. The synthesized marble hydroxyapatite (MA-Hap LR) powder was further formed into 2–3 mm pellets by extrusion spheronization technique using a polyvinyl alcohol binder. Continuous column defluoridation studies were conducted to obtain optimized column parameters such as input fluoride concentration, column inflow rates, optimum pellet size, and adsorbent bed parameters to obtain maximum fluoride adsorption capacity. The best breakthrough column performance was a maximum adsorption capacity of 1.21 mg/g, treating 10 mg/L fluoride concentration. The optimized column flow rate was at 1 LPH using an adsorbent bed height of 25 cm, which processed 28.5-bed volumes at an adsorbent exhaustion rate of 7.4 g/L. The column breakthrough performance data were fit into various kinetic models (Thomas model and Yoon–Nelson model) to describe adsorption kinetics and obtain correlation coefficients. Thomas’s model fitted well with a high correlation coefficient value. Modelling studies indicate MA-Hap as a promising adsorbent for drinking water treatment, and optimum column design parameters were identified for scale-up for real applications.

The present paper aims to reduce and detect the environmental impact of radioelement concentrations and waste marble powder (WMP) in the surrounding environment and additionally, improve the characteristics of the expansive soil and investigate the effect of stabilizers on the swelling soil to use a foundation layer. Different geotechnical laboratory tests have been performed on representative clay samples to define the physical and mechanical characteristics. The results indicate that the swelling pressure and swelling potential are reduced from (805.7 to 576 kN/m2) and (15.78 to 7.11%), respectively. The plasticity index decreased from 35.9% (high plasticity) to 19.4% (low plasticity), and the free swell index becomes zero by adding waste marble powder. Geospatial techniques have also been used to produce the distributions layers of different geotechnical characteristics and radioelements’ concentrations. These layers were integrated to produce a geospatial model. This model showed a noticeable improvement in the properties of clayey soils after the use of waste marble powder, which ranged from low expansion to high expansion. The radioelement concentrations of all samples are below an acceptable limit, except that the concentration of 40K is greater than the acceptable limit. This study recommends a 40% replacement of WMP. This amount is suitable and economical for this kind of treatment because of its positive solutions to protect the environment from pollution and reduce the cost of construction.

The use of wastes of marble powder (WMP) and dolomite as sorbents for CO2 capture is extremely promising to make the Ca-looping (CaL) process a more sustainable and eco-friendly technology. For the downstream utilization of CO2, it is more realistic to produce a concentrated CO2 stream in the calcination step of the CaL process, so more severe conditions are required in the calciner, such as an atmosphere with high concentration of CO2 (>70%), which implies higher calcination temperatures (>900 °C). In this work, experimental CaL tests were carried out in a fixed bed reactor using natural CaO-based sorbent precursors, such as WMP, dolomite and their blend, under mild (800 °C, N2) and realistic (930 °C, 80% CO2) calcination conditions, and the sorbents CO2 carrying capacity along the cycles was compared. A blend of WMP with dolomite was tested as an approach to improve the CO2 carrying capacity of WMP. As regards the realistic calcination under high CO2 concentration at high temperature, there is a strong synergetic effect of inert MgO grains of calcined dolomite in the blended WMP + dolomite sorbent that leads to an improved stability along the cycles when compared with WMP used separately. Hence, it is a promising approach to tailor cheap waste-based blended sorbents with improved carrying capacity and stability along the cycles under realistic calcination conditions.