Reuse of waste materials as construction material is very much essential to achieve sustainable construction. Utilization of waste materials as construction material not only help in protection of ...environment but also result in monetary savings. Spent Foundry Sand (SFS) is the waste material generated by metal casting industry. This paper presents study on economic and environmental benefits of recycling of SFS in concrete as sand replacement. Strength and durability properties of green concrete made with SFS as sand replacement are also presented. Natural sand in concrete was replaced with SFS at 0, 5, 10, 15 and 20% replacement levels by weight. To assess the performance of green concrete made with SFS, compressive strength, splitting tensile strength, deicing salt resistance and chloride permeability tests were performed. At age of 28 days, green concrete mixtures containing SFS as sand replacement displayed up to 26% and 12.87% improvement in compressive strength and splitting tensile strength over that of control concrete, respectively. Similarly, concrete mixtures made with SFS exhibited 7.2–17.7% lower chloride ion penetration and 6.6–26.42% improvement in salt scaling resistance on use of SFS. The green concrete mixtures showed very slight scaling after 50 cycles of freezing and thawing in the presence of deicing salt compared to slight to moderate scaling shown by control concrete. The incorporation of up to 20% SFS as sand replacement results improvement in strength and durability properties of green concrete over those of control concrete. Green concrete made with SFS is economical and reduces negative impact on environment by reducing CO2 emissions.
•Paper presents economic and environmental benefits of green concrete made with SFS.•Strength and durability properties of concrete improved on use of SFS as partial replacement of sand..•Green concrete made with SFS is economical and reduces negative impact on environment by reducing CO2 emissions.
► This paper is utilization of waste foundry sand (WFS) as partial replacement of fine aggregate. ► Fine Aggregates (Sand) has been replaced with 0%, 5%, 10%, 15%, and 20% WFS. ► Strength properties ...such as compressive strength, splitting tensile strength, and modulus of elasticity were investigated. ► Ultrasonic Pulse Velocity and permeability (chloride) were also studied. ► In this investigation, WFS studied results in denser and durable concrete.
Ferrous and non ferrous metal casting industries produce several millions tons of byproduct in the world. In India, approximately 2
million tons of waste foundry sand is produced yearly. WFS is major byproduct of metal casting industry and successfully used as a land filling material for many years. But use of waste foundry sand (WFS) for land filling is becoming a problem due to rapid increase in disposal cost. In an effort to use the WFS in large volume, research has being carried out for its possible large scale utilization in making concrete as partial replacement of fine aggregate.
This experimental investigation was performed to evaluate the strength and durability properties of concrete mixtures, in which natural sand was partial replaced with (WFS). Natural sand was replaced with five percentage (0%, 5%, 10%, 15%, and 20%) of WFS by weight. A total of five concrete mix proportions (M-1, M-2, M-3, M-4 and M-5) with and without WFS were developed. Compression test and splitting tensile strength test were carried out to evaluate the strength properties of concrete at the age of 7, 28 and 91
days. Modulus of elasticity and ultrasonic pulse velocity test were conducted at the age of 28 and 91
days. In case of durability property, Rapid Chloride Permeability test was performed on all five mix proportion at the age of 28 and 91
days. Test result indicate a marginal increase in strength and durability properties of plain concrete by inclusion of WFS as a partial replacement of fine aggregate.
This research is about the utilization of two solid wastes in concrete: foundry sand from the steel smelting process and residual aggregate powder from the asphalt mix production. The solid wastes ...were added to concrete in contents of 0.0, 5.0, 10, 15, and 20 wt% with respect to cement, and tested in concrete with a design resistance of 280 kgf/cm2 (27.5 MPa). The effects of these wastes in concrete were compared with commercially available metakaolin, a typical admixture added to concrete, in contents of 0.0, 5.0, 10, 15, and 20 wt% replacing cement content. For all samples, the resistant activity index was evaluated at 28 days. Slump test, air content, density, and compressive strength tests were conducted. The materials’ microstructures were evaluated with SEM and XRD after 270 days, in samples immersed in water. Results show that both by-products have pozzolanic activity, classified as N-type pozzolans. Besides, concrete with the residual aggregate powder gave a strength of 541 kgf/cm2 (53.1 MPa), which corresponds to sample M4 (concrete containing 15% residual aggregate powder), consistent with 93% improvement with respect to the strength resistance. Furthermore, concrete with the foundry sand powder gave a strength of 561 kgf/cm2 (55 MPa), consistent with 100% improvement with respect to the strength resistance, which corresponds to M15 (concrete containing 20% foundry sand). Concrete with the metakaolin powder presented a strength of 609 kgf/cm2 (59.7 MPa), which corresponds to M9 (concrete containing 15% metakaolin), consistent with 116% improvement with respect to the strength resistance. The concrete developed with the by-products can be produced at lower costs than traditional admixtures, which guarantees the feasibility of the environmental solution.
Metal smelting generates a significant volume of industrial solid waste foundry sand (WFS). Although several standards and studies have established practices and requirements for its use, a large ...portion of the disposed WFS goes to industrial landfills. This study aims to evaluate the value of WFS as an aggregate in hot-mix asphalt mixtures (HMA) using systematic criteria for classification, potentialities, waste generated and applicability. To this end, molding sand (MS) and fine dust of exhaustion (FDE) were characterized, to identify their potential for application as aggregates in asphalt mass. Different contents of MS, FDE, and Blend (BL) were studied according to the normative granulometric ranges of aggregates for HMA. Samples were obtained via the Marshall method to verify important properties for the asphalt mix. Ecotoxicity tests were conducted. The results showed that a composition containing 10 wt% of BL presented an air void volume of 3.3%, a stability of 658 kgf, creep of 2.5 mm, and an indirect tensile strength of 0.93 MPa. From a technical and environmental perspective, a 10 wt% BL content was suitable for recovery into HMA. Lower amounts BL yielded results outside the normative limits. WFS can be recovered and applied as a raw material in HMA.
Waste foundry sand (WFS), a by-product of the casting industry, is a potential material that may be employed as a substitute for fine aggregate in concrete. In the present study, gene expression ...programming (GEP) and multi-expression programming (MEP) are used to generate predictive models for the split tensile strength (STS) and elastic modulus (E) of waste foundry sand concrete (WFSC). Therefore, a comprehensive database was collected that contains 146 and 242 values of E and STS, respectively. Seven different variables were chosen as input for the development of the ML-based models. The reliability and accuracy of the proposed model were evaluated by using various statistical indicators. Given the performance assessment, both GEP and MEP accurately predict the E with a correlation of 0.994 and 0.996, respectively. However, GEP performance was much superior in predicting STS (R = 0.987) as compared to the MEP model (R = 0.892). The integrated statistical performance (ρ, OF) of both models approaches zero, indicating the excellent performance and generalization potential of the developed models. For the interpretation of machine learning (ML) models, Shapley additive explanation (SHAP) was used to know about the input variables' importance and influence on the output parameter. The SHAP analysis revealed that a higher ratio of FA/TA results in the enhancement of the elastic modulus, whereas CA/C higher ratio is favorably influencing the split tensile strength up to some extent, however, this trend changes when the ratio is further increased. These soft computing prediction techniques can incentivize the use of WFS in sustainable concrete, reducing waste disposal and promoting environment-friendly construction. Furthermore, it is recommended that the findings of this study be validated with more extensive data sets and that other ML techniques be investigated.
Lack of providing sustainable solutions towards resource efficiency through product-life extension, redistribution, remanufacturing, recycling, as well as re-engineering of wastes to maintain ...economic, society, and ecological balance, are the challenges facing the environment in the last decades. This article reports on the findings of an investigation into the utilization of scrap plastic wastes (SPW) and foundry sand (FS) in the production of green efficient bricks for masonry structures. Series of bricks were produced in varying ratios of 20 %, 30 %, and 40 % of the mass of FS. The produced bricks were tested for durability through acid, and water soaking and subsequently tested for compressive and tensile strength, to evaluate the brick's strength indices compared to conventional fired clay bricks. Results from this investigation showed that all the bricks produced from FS and SPW recorded 85 % strength greater than that of fired clay bricks. The ratio of 70 %: 30 % FS: SPW rendered the highest strength values followed by 60 %: 30 % and 80 %: 20 % for tensile and compressive tests, respectively. The result further showed that the compressive strength of SPW bricks is twice greater compared to that of clay fired bricks as they both recorded 29.45 MPa and 14 MPa, respectively. The SPW bricks portrayed low water absorption and retained their ultimate strengths after soaking in different acid concentrations. As such possesses the salient capacity in an acidic environment compared to clay bricks. The strength indices (qt/qu) of 0.18 to 0.28 as the proportionality of tensile and compressive strength is closely correlated to all the SPW bricks due to hydrophobic and deformability characteristics of the scrap plastic. The findings illustrated a rational approach towards the conversion of wastes into green-efficient construction material.
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