Contamination of urban surface waters by herbicides is an increasing concern; however, sources of contamination are poorly understood, hindering the development of mitigation and regulatory strategies. Impervious surfaces, such as concrete in driveways and paths are considered an important facilitator for herbicide runoff to urban surface waters following applications by residential homeowners. This study assessed the transferability of a herbicide from concrete pavers treated with an off-the-shelf product, containing simazine as the active herbicide, marketed for residential homeowner application to impervious surfaces. Commercially available pavers were treated according to label directions and the effects of exposure time prior to irrigation, repeated irrigations, and dry time between irrigations on transferability of simazine to runoff were assessed. Simazine transferability was greatest when receiving an initial irrigation 1 h after application, with concentrations in runoff reduced by half when exposure times prior to the first irrigation were >2 days. Concentrations remained stable for repeated irrigations up to 320 days and exposures to outdoor conditions of 180 days prior to a first irrigation. Dry time between irrigations significantly influenced simazine transfer to runoff. Dry periods of 140 days resulted in approximately a 4-times increase in simazine transferability to runoff. These results suggest that herbicides used by homeowners, or any other users, on impervious surfaces are available to contaminate runoff for prolonged time periods following application at concentrations that may pose risks to aquatic life and for reuse of harvested runoff on parks and gardens. Regulators should consider the potential of hard surfaces to act as reservoirs for herbicides when developing policies and labelling products.

Generation of solid waste and its improper disposal approaches poses severe threat to the environment, animals, and the human community which may affect the ecosystem. The generation of waste by the human community cannot be avoided but the impact from it can be minimized in various ways. One such approach is to utilize the by-products obtained from the waste through proper techniques and methods. So, in this paper, an attempt is done to use compost as a replacement for M sand and to check its feasibility in manufacturing light-weight concrete. Also, ground granulated blast furnace slag (GGBS) is used as a replacement for cement whereas pumice stone is used as the coarse aggregate. Initially, the physical, chemical, and microstructural properties of the raw materials are studied. Then, the concrete specimens are casted for M25 grade and the specimens are tested for compressive strength at 7 and 28 days of age. It is observed that the GGBS at 10% for cement and compost up to 20% for M sand showed higher compressive strength which is sufficient for light-weight concrete. Hence, it can be said that the utilization of compost can minimize the waste disposal and it can be managed effectively.

Exposing concrete to high temperatures leads to harmful effects in its mechanical and microstructural properties, and ultimately to total failure. In this sense, various types of waste materials are exploited not only to tackle serious environmental issues but also to enhance the thermal stability of concrete exposed to elevated temperatures. Furthermore, nanomaterials have been incorporated in concrete as admixtures to reduce the thermal degradation of concrete due to exposure to high temperatures. In the present study, the effects of nanosilica (NS) incorporation on the properties of concrete subjected to elevated temperature are discussed in several sequential sections. The process mechanism of concrete deterioration due to fire exposure and the important factors that could affect the performance of concrete under fire were evaluated. Moreover, brief highlights on the effect of elevated temperature on concrete containing waste materials are included in this review paper. Reviews and summaries of the available and updated literature regarding concrete containing NS are considered. According to the findings of the studies under review, the addition of nanosilica to concrete contributed in reduced strength loss, minimized internal porosity, and enhanced matrix compactness in concrete.

Adding a corrosion inhibitor to the chloride deicing salt can prevent the corrosion and pollution of Cl⁻, which is very important. Layered double hydroxide (LDHs), calcined at high temperature is used as adsorbents to remove various anionic contaminants, and it can reduce the freezing point of solution after adsorbing anions. Therefore, this paper reports the use of calcined LDHs as corrosion inhibitors in deicing salts, which are denoted as MgAlOₓ or MgAlFeOₓ depending on the preparation element. By analyzing the removal efficiency and the freezing point of MgAlOₓ and MgAlFeOₓ to Cl⁻, the feasibility of the study was determined. Resulted that the removal efficiency to Cl⁻ of MgAlFeOₓ at low temperature (0 ± 2 °C) and room temperature (25 ± 2 °C) was higher than that of MgAlOₓ, reaching 39.4% and 85.60%, respectively. And the freezing point of MgAlFeOₓ was lower than that of MgAlOₓ, the value was −12.0 °C. At the same time, we also found that CaCl₂-MgAlOₓ and CaCl₂-MgAlFeOₓ significantly reduced the corrosion of carbon steel and concrete compared with chloride salts, and CaCl₂-MgAlFeOₓ had the lowest corrosion degree. Hence, MgAlFeOₓ was chosen as the corrosion inhibitor in chloride deicing salt. The metal molar ratio, synthesis temperature, and calcination temperature for preparation of MgAl/MgAlFe-LDHs were determined by XRD and TG-DSC analysis that were 9/2/1, 120 °C, and 500 °C, respectively. Characterization methods such as Zeta, XRD, XPS, BET, and SEM were used to study in detail the characteristic changes of MgAlFe-LDHs and MgAlFeOₓ after Fe³⁺ was added, and the mechanism of corrosion inhibitors was further determined that was achieved by adsorption and neutralization.

Mining and extraction of stones and minerals play a significant role in many countries economic growth in the world. The production of dolomite minerals in various industries in India and other countries produces vast amounts of waste in different fractions. Disposal of these types of industrial wastes in an immense quantity causes environmental pollution. The performance of dolomite mining residues on concrete properties as a fine aggregate substitute was examined. The microstructural analysis was conducted on the concrete samples to find the effect of dolomite mining residues in concrete. The stress–strain behaviour of the dolomite mining residues concrete was studied. The effect of exposure to elevated temperature and freeze–thaw on concrete properties containing dolomite mining residues was found up to 100% at 10% incremental order. The thermogravimetric analysis (TGA) and differential thermogravimetry (DTG) tests were conducted on the dolomite mining residues and concrete samples. As a test result, concrete properties influence with the incorporation of the dolomite mining residues as a substitution of river sand, but no significant effect is observed in the concrete properties containing 10% dolomite mining residues. Up to 10% of dolomite production waste can be used as a sand substitute in concrete and other applications for sustainable development.

It has recently been shown that pervious concrete is a promising, effective technology as a permeable reactive barrier system for treatment of acid mine drainage (AMD). However, pore clogging also occurs simultaneously during AMD treatment. In the present study, mixtures of pervious concrete were made and used in a column experiment during which pore clogging occurred in the samples. Pore volume, connectivity and other parameters of pervious concrete were evaluated using five (5) different methods comprising the volumetric method (VM), linear–traverse method (LTM), image analysis (IA), falling head permeability test and X-ray microcomputed tomography. It was found that pervious concrete effectively removed from AMD, about 90 to 99% of various heavy metals including Al, Fe, Zn, Mn and Mg. Cr concentration significantly increased in the treated effluent, owing to leaching from cementitious materials used in mixtures. The VM and LTM gave statistically similar pore volume results, while IA’s values were 20 to 30% higher than those of the conventional methods. The falling head permeability test and IA were found to be effective in quantifying pore clogging effects. Pervious concrete exhibited high pore connectivity of 95.0 to 99.7%, which underlies its efficacious hydraulic conductivity.

Concrete is widely used as a building material all over the world, and its use is increasing the demand of cement and sand in the construction industry. However, the limited resources and environmental degradation are driving scientists to develop alternative materials from vast volumes of agro-industrial wastes as a partial replacement for conventional cement. In the manufacture of concrete, cement is a major binding resource. This study looked into recycling agro-industrial wastes into cement, such as sugarcane bagasse ash (SCBA), coal bottom ash (CBA), and others, to create sustainable and environmentally friendly concrete. This study aims to see how the combined effects of agricultural by-product wastes affected the characteristics of concrete. SCBA is used to replace fine aggregate (FA) ranging from 0 to 40% by weight of FA, while CBA is used to replace cement content ranging from 0 to 20% by weight of the total binder. In this case, a total of 204 concrete samples (cubes and cylinders) are made using a mixed proportion of 1:1.5:3 and a water-cement ratio of 0.54. Workability, density, water absorption, and mechanical characteristics in terms of compressive and splitting tensile strengths were examined in this study. In addition, for each mix percentage, the total embodied carbon was determined. Workability, density, and water absorption were found to be considerably decreased when CBA and SCBA concentration increased. Due to the pozzolanic nature of CBA and SCBA, an increase in compressive and splitting tensile strengths were seen for specific concrete mixtures, and further addition of CBA and SCBA, the decrease in strength. The embodied carbon of SCBA has augmented the total embodied carbon of concrete, though it can be seen that C15S40, which comprises of 15% CBA and 40% SCBA, is the optimum mix that attained tensile and compressive strength by 3.05 MPa and 28.75 MPa correspondingly, with a 4% reduction in total embodied carbon.

Concrete is one of the most important materials that are used in the construction industry all around the world. A larger part of the capacity in concrete is generally employed by the coarse aggregate. Due to the tremendous use of coarse aggregate in the construction industry, the material is getting degraded. In order to preserve the natural material, we are in search of an alternate material that can be used in concrete instead of the original one. So in this research work, it has been attempted to study the mechanical behaviour of lightweight concrete when we use waste coconut shell as coarse aggregate inside concrete. To improve the strength of the concrete, we also use the sisal fibres in various proportions ranging between 1 and 5% in accordance to the binder weight. After the mechanical property tests such as the compression test, spilt tensile strength, flexural test, modulus of elasticity test, and impact resistant test were conducted, finally it was concluded that there was increment in the compression strength up to 5%, and tensile strength was increased to 17% and elastic modulus to 7% when the fibre content used was 3%. Thus, with the use of these waste materials, it was found that the concrete’s strength gets increased and it leads to the formation of sustainable concrete thus reducing the pollution in the environment.

Durability performance of concrete is enhanced by adding supplementary cementitious materials such as fly ash. The concrete made with addition of fly ash with Portland cement is called fly ash cement concrete (FACC). Generally, modelling approach is applied to predict the service time of concrete in aggressive environment. Most degradation of concrete is found in marine environment, due to the exposure of concrete to chlorides. Service life modelling is performed using diffusion equation (Eq. 1) with diffusion coefficient (D) equation (Eq. 2), and to get the diffusion coefficient (D) over time, ageing factor is used for analysis. During modelling stage, as this phase of study is started well before construction, concrete for its durability performance is checked. As well, service life modelling is performed for the existing structures, so that the time to failure may be obtained. In recent times, failure of Miami Building, USA, June 2021, has raised the importance of service life modelling (SLM) of reinforced concrete structures (RCC) in chloride environment. So, in such environments, a more need of more reliable results is raised. Presence of a number of ageing factors in literature raises a question which ageing factor is more approximate. Dependency of performance of modelling approach is on the selection of more approximate values. So, in present study, performance of ageing factors for fly ash cement concrete (FACC) is checked. So, literature was surveyed and the long-term chloride diffusion coefficient (D) values were obtained for fly ash cement concrete (FACC). It was found that a significant difference is present in the predicted values with different available ageing factors. Since results obtained from modelling depend on the parameters, so it can be assumed that the variation of chloride diffusion coefficient (D) will vary the results. So, in present study, a new ageing factor was developed. Service life modelling for durability with fly ash cement concrete (FCC) may be relied on the newly developed ageing factors, as this will give better results, which will be more reliable.

Increased water demand due to population growth and industrialization has led to increased water consumption. Hence, it is required to find an alternative to water in different industries. Concrete represents a remarkable water-consuming industry. The present study investigates whether the treated leachate of municipal landfills can be employed as a substitute for water in the concrete mixing scheme. For this purpose, concrete samples fabricated at different concentrations of treated leachates were compared to the control sample containing distilled water in terms of unconfined compressive strength (UCS) at the ages of 7 and 28 days. The experimental results revealed treated leachate accelerated the cement setting time by nearly 15 min and increased concrete slumping by 16%. The complete replacement of distilled water with treated leachate decreased UCS by 25% (from 50 to 38 MPa). The scanning electron microscope (SEM) and ultrasonic results showed that a rise in the treated leachate content of concrete increased porosity. Increased porosity would reduce UCS. Leaking of heavy metals existing in the leachate should be also investigated for the solidified matrices. The toxicity characteristic leaching procedure (TCLP) revealed that heavy metals leaching in all the samples are in the acceptable range. Results have shown that the use of leachate up to a concentration of 20% can be used in concrete, and the solidified product can also stabilize the pollutants, successfully. It is a valuable finding because using treated leachate as a practical additive in the concrete can prevent environmental contamination.