Mohamed Darwish, Mohamed Elnakeb, Marina Moawad
et al.
The construction field is one of the largest sectors and industries worldwide. This industry is the main industry accused of contributing to greenhouse gases and increasing the effects of climate change. However, the construction industry is indispensable, accordingly in an attempt to decrease the greenhouse gas effects of construction this research presents the manuscript for building a one-story building with all components including waste products. The building model used a strip foundation with a concrete mix design incorporating recycled concrete as a partial replacement for aggregates, cement hollow blocks containing granite waste instead of conventional cement blocks, and sandwiched insulated panels made of wood-plastic composites for the roof. The structural soundness of the system was tested by loading it with a load surpassing its design load in addition to measuring the deflection and checking its abidance to the code limitations. The thermal efficiency was tested by measuring the temperatures in comparison with the outside of the building for a span of 7 days with data recorded every 1 h. Analysis of both the short-term and long-term costs and carbon emissions was performed by acquiring the carbon emissions per unit of material from literature and multiplying it by the quantities of the materials used within the different building alternatives. That study showed that the roofs made of Structural Insulated Panels (SIPs) using Wood-Plastic Composite (WPC) facings when used with hollow-block cement block walls have shown enduring cost efficiency and improved thermal insulation, leading to diminished energy usage, life-cycle expenses, and carbon emissions. Furthermore, the proposed system is more environmentally friendly than conventional reinforced concrete technologies due to their lower costs and emissions in addition to improving sustainability through utilizing recycled materials.
Dani Akhmad Imaduddin, Harimukti Wandebori, Mohammad Hamsal
The steel industry plays a crucial role in national development. Major global steel producers such as the United States, Russia, and Japan have seen declines due to the rise of China as a dominant steel producer. Integrated Steel Corporation (ISC) in Indonesia has also faced declining performance, with its market capitalization dropping by 68.9% over the past eight years. The research primarily aimed to analyze customer preferences in the maintenance industry and determine positioning strategies. Additionally, it sought to identify the factors driving the formation of the Strategic Maintenance Services (SMS) spin-off from ISC and propose strategies for SMS to achieve a competitive advantage. Data were collected qualitatively through interviews and Focus Group Discussions (FGDs) with customers to understand their perspectives, SMS management to grasp core business competencies and strategy, and ISC management to understand the parenting strategy. The results show several internal dynamics within ISC drove the formation of the SMS spin-off: 1) the transformation of the parent company; 2) short circuit incident at the main ISC factory; and 3) the cost burden of maintenance support. External factors indicate rapid industrial growth and the company's strengthening as a group after experiencing losses for almost a decade. The proposed strategy for SMS involves leveraging ISC’s subsidiaries and joint venture companies for centralized service maintenance. SMS aims to offer customized one-stop maintenance solutions with high quality at competitive prices by enabling Digital Maintenance Information (DMI). The target markets include large industries in steel manufacturing, petrochemicals, flour mills, cement, and logistics.
Despite extensive research efforts, understanding the time-dependent behavior of concrete remains an enigma due to the complex nature of cement microstructure. In this study, the statistical nanoindentation was employed to investigate the influence of relative humidity (RH) on the relaxation behavior of calcium silicate hydrates (C-S-H) in a cement paste. Our experiments, performed at RH levels of 33 % and 86 %, revealed significant enhancements in both the indentation modulus and hardness of the C-S-H as RH increased. Remarkably, the internal water exerted a significant influence on the asymptotic relaxation behavior, displaying a clear power-law fashion. Further analysis identified the presence of short- and long-term viscoelastic behaviors within the C-S-H, distinguished by a transition observed within the initial seconds. These findings advance the understanding of nanoscale mechanisms driving concrete creep under different humidity conditions.
Today, the issue of optimizing fuel consumption in cement plants is considered an effective factor in determining the cost price of the product and is being pursued more seriously by energy management organizations. Optimizing and reducing fuel consumption, especially to preserve national economic resources, is one of the important goals of every country. In recent years, this issue has also received special attention in Iran and industries are looking for effective economic solutions in this field. One of the solutions to reduce energy consumption in this industry is to study the effect of LSF, SM, AM, LP and 90-micron sieve residue parameters on preheater and kiln fuel consumption, which has not been studied and investigated much to date. In this article, we modeled the effect of these chemical modules on the fuel consumption of the Zabol Cement Industries Company's firing system using Design Expert software and the response surface methodology. The method studied is for optimizing fuel consumption in the preheater and cement kiln, and kiln fuel consumption is considered as the response variable. The results of this research show that among the chemical modules used for furnace feed analysis, the LSF and AM values have the greatest impact on fuel consumption (the more these two parameters tend to increase, the more kilocalories are consumed), but the LP parameter has the opposite effect, that is, it decreases with increasing fuel consumption, and the 90-micron Residual sieve is not seen in the model due to its constant range of changes.
Nowadays, construction industries are using flyash as a potential alternative for cement. Due to its improved mechanical properties, ecofriendly nature, and low cost, geopolymer technology makes use of flyash as a promising future binder material. In this paper, 7 factors such as liquid-to-flyash ratio, silicate-to-hydroxide ratio, curing temperature, curing period, concentration of NaOH (molarity), rest period prior to curing, and dosage of superplasticizer that influence the compressive strength and temperature drop are screened using the Plackett–Burman method for optimization. Here, compressive strength and temperature drop are taken as the main indices of response to analyze the parameters. The significant variables determined from the Plackett–Burman design are further considered for the process of optimization using the response surface methodology. From the analysis, the optimum values of 0.4071 liquid-to-flyash ratio, 2.5 silicate-to-hydroxide ratio, and 6 hours curing period give maximum compressive strength and temperature drop of 28.87 MPa and 5.3°C under the optimized medium in the validation experiment which varies by only 3.93% and 1.85% from the observed value of 27.20 MPa and 5.4°C.
The concrete industry faces an urgent need to identify new supplementary cementitious material (SCM) sources. One class of materials available in large volumes are basaltic materials, which are often stockpiled in landfills as a waste product from quarries and granule operations. Reactivity testing on some such materials has shown them to be inert. The thermal activation of basaltic fines, and their mixtures with fly ash and limestone was therefore evaluated in a furnace using different process variables. Physical and chemical characterization using X-ray diffraction, Fourier transform infrared spectroscopy, and electron microscopy was performed on the raw and thermally activated materials. The reactivity of the resulting materials was directly measured. Heating beyond 1300 °C and cooling results in complete amorphization for the tested materials and resulted in the highest reactivity. Thus, the activation of basaltic fines into SCMs is feasible, although optimization to reduce temperatures is needed.
Haider M. Mekkiyah, Yasir A. J. Al-Hamadani, Ali A. Abdulhameed
et al.
Crude oil still affects many countries because it is one of the essential fuel sources. It makes life more manageable in modern communities and cannot be overstated because it is easy to use and find. However, the pollution caused by its use in industries such as mining, transportation, and the oil and gas business, especially soil pollution, cannot be ignored. Soil pollution is an issue in most communities because it influences people and ecology. Accidental infusions and spills of ore oils are prevalent occurrences leading to the entire or fractional exchange of the soil pore fluid by oil-contaminated soils that have affected the geotechnical engineering properties. The liquid limitations for polluted soil grades silty loam and sandy loam decreased by 38% and 16%. Oil contamination leads to decreased permeability; the permeability values for sandy loam soil decreased from (3.6 × 10<sup>−6</sup> to 0.25 × 10<sup>−6</sup> cm/s) when the oil content increased from 0 to 16%; however, the permeability values for silty loam decreased from (2.6 × 10<sup>−6</sup> to 0.25 × 10<sup>−6</sup>) cm. The current study results exhibit that the geotechnical properties of contaminated soil with oil slag can be modified upon adding cement at different weight percentages (3, 5, and 7%) to the soil. The Atterberg limits and specific gravity of the soil were noticeably reduced when it was stabilised with cement, as well as because oil spills on soil significantly influence the environment. So, there is an immediate and critical need for efficiently removing petroleum hydrocarbon pollutants from contaminated soil. Bioremediation is a new technology gaining interest worldwide to clean up sites that have polluted petroleum hydrocarbons.
The organ of vision is one of the target organs, which is negatively influenced by a number of harmful factors of the working environment and the labor process. Under their influence, the functioning of the visual analyzer can be disrupted, the risk of developing various diseases and injuries increases. The problem of the ophthalmopathology development in persons employed in hazardous industries is relevant, since the protection of the health of the working-age population is of great socio-economic importance. The proposed review of the literature presents the structure and frequency of occurrence of ophthalmopathology in workers of the cement industry, oil refining and petrochemical industries, metallurgical industry, coal and mining industries, manganese ore industry, synthetic rubber production, rubber technical products, synthetic ethyl alcohol, bakery, aviation production, also workers of the underground and railways of the main professions, including those who service underground tunnels. The data of the nosological structure of ophthalmopathology of various hazardous industries workers in Ukraine, India, and some African countries are presented. Among the professionally conditioned pathology of the vision organ, diseases of the anterior part of the eyeball are most common: chronic conjunctivitis, blepharitis, blepharoconjunctivitis, dry eye syndrome. In the general diseases’s structure of the vision organ, the first place is occupied by anomalies of refraction (from 14.3 to 88.9 %). The share of eye injuries ranges from 4 to 12.5 %. The frequency of occurrence of various ophthalmopathologies increases among workers with more than 10–15 years professional experience, which is typical for all industries and industries; there is also a direct connection between diseases of the organ of vision and the class of harmfulness of working conditions.
Manvendra Verma, Nirendra Dev, Ibadur Rahman
et al.
Geopolymer concrete (GPC) is a new material in the construction industry, with different chemical compositions and reactions involved in a binding material. The pozzolanic materials (industrial waste like fly ash, ground granulated blast furnace slag (GGBFS), and rice husk ash), which contain high silica and alumina, work as binding materials in the mix. Geopolymer concrete is economical, low energy consumption, thermally stable, easily workable, eco-friendly, cementless, and durable. GPC reduces carbon footprints by using industrial solid waste like slag, fly ash, and rice husk ash. Around one tonne of carbon dioxide emissions produced one tonne of cement that directly polluted the environment and increased the world’s temperature by increasing greenhouse gas production. For sustainable construction, GPC reduces the use of cement and finds the alternative of cement for the material’s binding property. So, the geopolymer concrete is an alternative to Portland cement concrete and it is a potential material having large commercial value and for sustainable development in Indian construction industries. The comprehensive survey of the literature shows that geopolymer concrete is a perfect alternative to Portland cement concrete because it has better physical, mechanical, and durable properties. Geopolymer concrete is highly resistant to acid, sulphate, and salt attack. Geopolymer concrete plays a vital role in the construction industry through its use in bridge construction, high-rise buildings, highways, tunnels, dams, and hydraulic structures, because of its high performance. It can be concluded from the review that sustainable development is achieved by employing geopolymers in Indian construction industries, because it results in lower CO<sub>2</sub> emissions, optimum utilization of natural resources, utilization of waste materials, is more cost-effective in long life infrastructure construction, and, socially, in financial benefits and employment generation.
José S. Andrade Neto, Bruna B. Mariani, Nilson S. Amorim Júnior, Junior
et al.
The incorporation of different levels of UOW into Portland clinker raw meals and its effects on the clinker and cement properties were evaluated. Clinkers were produced and characterized by X-ray diffractometry (XRD) and optical microscopy; the cements were produced and physically characterized. Finally, pastes were produced and analyzed using isothermal calorimetry, thermogravimetry, XRD, and compressive strength tests. UOW, when added up to 1.29% in Portland clinker raw meal, acts as a mineralizer, increasing the content of alite by 6.44%. The incorporation of UOW reduces the hydration rate in the first days owing to the increase in the size of the alite crystals and delays the point of sulfate depletion due to the increase in the SO3 content of the clinkers. Owing to the higher content of alite formed, the cement produced from the raw meal with 1.29% of UOW presents the highest early mechanical strength (up to 7 days).
Panagiotis Grammelis, Nikolaos Margaritis, Petros Dallas
et al.
Annually, approximately 3 billion tires are commercially transacted worldwide each year and an equivalent amount is disposed of by the end of their life. Despite the increase in the life of tires and the global economic and pandemic crisis, the number of discarded tires is going to rise further due to the increasing demand for vehicles worldwide (approximately 5 billion tires by the end of 2030). The obsolete methods of tire disposal, including landfill, burning, etc., are a responsible for environmental issues (harmful substances production, air and soil pollution) and for the transmission of various diseases. Nowadays, approximately 70% of the total tires at the end of their life (ELTs) is recovered. The largest percentage of the recovered ELTs is intended for energy production or recovery as a fuel in cement industries or can be used for the production of various materials. A significant amount (approximately 95%) of the discarded ELTs can be reused. The products from the processing of ELTs can be fragments of different sizes and types, including: Trimmed rubber (70% by weight), steel wire (5–30% by weight), and fluff or textile fibers (up to 15% by weight). From the aforementioned materials, rubber and steel wires are mainly recovered and used for numerous applications. However, current ways of utilizing these materials will have to adapt or change in the near future, in order to comply with stricter regulations. The purpose of the current study is to sufficiently review recent progress on the management of ELTs, focusing on alternative uses of textile fibers such as additive for sound absorbing materials, bituminous conglomerates, concrete production, plastic materials, soil reinforcement, etc.
Sumon Kumar Das, Masum Miah, Md. Rubel Miah
et al.
Research aim: The core objective of this study is to identify the nature and extent of sustainability reporting disclosure practices among Bangladeshi listed companies, in line with global reporting initiatives (GRI).
Design/Methodology/Approach: The content analysis method is used in this study to examine a total of 48 items, consisting of 17 environmental and 31 social disclosure items, in line with GRI. Data were drawn from the published annual reports of a sample of 51 listed companies for the financial year of 2016/2017.
Research findings: On average, 13.73% of the sample companies did not disclose any issue on sustainability reporting. The overall sustainability reporting index of these companies is 10.70% (environmental: 11.42% and social: 10.31%). The level of overall disclosure is low, with the Cement industry focusing on both social (21.18%) and environmental (14.19%) areas, the Textile industry mainly focusing on the environmental (17.06%) area, and the Bank industry mainly focusing on the social (25.16%) area. There is a paucity of disclosure of both social and environmental issues in Food & Allied and Pharmaceuticals & Chemicals industries. Companies are reluctant to disclose issues related to emission, effluent, waste, and compliance under the environmental dimension, and human rights and social performance indicators under the social dimension.
Theoretical contribution/ Originality: Several studies have been conducted on either corporate social reporting or environmental reporting, but there is a dearth of an integrated investigation into the level of sustainability reporting practices in Bangladesh. This study enumerates the sustainability reporting practices in Bangladesh based on the most recognised global non-financial reporting standard, namely GRI.
Practitioner/ Policy implication: With the growing awareness among stakeholders and the initiatives taken by regulators, there might be an increasing trend in sustainability reporting practices. This study is expected to contribute to the introduction of more regulatory requirements for a comprehensive framework on sustainability reporting.
Research limitation: This study focuses on only quantity and not quality in preparing the disclosure index and considers only one period.
Keywords: Social Reporting, Environmental Reporting, Sustainability Reporting, Global Reporting Initiatives, Bangladesh
Type of Manuscript: Research paper
JEL Classification: M14
Mohannad Nassar, Rania Nassar, Rania Nassar
et al.
Inositol hexaphosphate (IP6) is the most abundant inositol phosphate in nature and an essential molecule for different biological functions. IP6 has a unique structure granting it distinctive properties; a high negative charge density provides IP6 with an immense chelating ability and valuable antioxidant properties. IP6 is also simple and cost-effective to produce. These features have attracted researchers and entrepreneurs to further study IP6 for a wide variety of applications in areas such as pharmaceutical, food and chemical industries, medicine, pharmacy, nutrition, and dentistry. The interest in IP6 in the dental field unfolded many decades ago following identification of a cariostatic ability and a positive impact on reducing enamel dissolution. Subsequently, IP6’s anti-plaque, anti-calculus and cement-forming properties have been investigated. Despite encouraging findings, there was a phase of decreased attention to IP6 which slowed down research progress. However, the potential use of IP6 has recently been revisited through several publications that provided deeper understanding into its mechanisms of action in the aforementioned applications. Studies have also explored new applications in endodontics, adhesive, preventive and regenerative dentistry, and IP6’s role in improving the characteristics and performance of dental materials. Evidence of the merits of IP6 in dentistry is now substantial, and this narrative review presents and discusses the different applications proposed in the literature and gives insights of future use of IP6 in the fields of orthodontics, implant and pediatric dentistry.
Large amounts of cotton microwastes are accumulated in textile industries. The cotton microdust is less to ignite and causes serious environmental problems and health hazards. This paper presents an experimental study, which investigates the potential use of cotton microdust to produce new and lightweight brick for construction industries. The physical and mechanical properties of brick mixes having different levels of cotton microdust ratio were investigated. The test results recorded for compressive strength, unit weight, and water absorption values satisfy the relevant required standards for normal construction bricks. The results show that the replacement of clay soil and cement by cotton microdust does not exhibit a sudden brittle fracture even beyond the failure loads, indicates high energy absorption capacity, reduces the unit weight dramatically, and introduces smother surface compared to the current concrete bricks in the market. The results also show that usage of cotton microdust with different mixing ratios for bricks will give light-weight composite, and brick could be an economical alternative to be used for partition of board concrete blocks and sound barrier panels.
The aim of this study is that the to evaluate the effect of financial leverage and operating leverage on the systematic risk of stock. In trendy competitive business era, the power to extend come of the firm is usually depends on economical use of leverage within the capital structure. Leverage is outlined as an extended term debt funding that improves the permanent financial performance yet because the success of the organization. It conjointly explained because the use borrowed funds to ascertain investment and come thereon investment however it’s a lot of risky if they can’t be ready to generate higher rate of come in compare with value of capital. For this reason, the determination of the proportion of debt and equity is one in every of the foremost essential choices that the organization faces, and any variability in leverage will influence a company’s monetary capability, risk, return, investment, strategic call and therefore the wealth maximization of organization. During this study, financial leverage and operating leverage as independent variables and systematic risk because the variable is considered. This study used a quantitative analysis style. The population of the study was created from the 8 cement industries of Pakistan. The study used secondary knowledge that was obtained from the annual audited monetary statements that had audited and revealed by securities market of Pakistan for an amount of five years between 2014 and 2019. This study used a correlation analysis and a multiple rectilinear regression technique in analyzing the collected knowledge. The study found that financial leverage and operating leverage had a big positive relationship with systematic risk of stock. This study covers that financial leverage and operating leverage have an immediate result on the systematic risk of stock in a very companies’ come. The study counseled that management of corporations listed at the securities market to draw in smart management therefore to beat the danger of stock. Whereas important at ≤ 0/05 H0 hypothesis, is rejected. Otherwise, there’s no different adequate reason for rejecting H0 hypothesis. For testing the hypothesis of this study, rectilinear regression technique has been used. In step with the results obtained, H0 is rejected because of important = zero.00< 0.05. This analysis is 100% because of all knowledge is collected from the correct places.
Mary Lissy P.N., Carolin Peter, Kavya Mohan
et al.
Clay brick manufacturing is a sector which involves a lot of firing processes requiring higher temperature. To maintain this temperature, large amount of fuel in the form of wood, coal, biomass etc. need to be burnt in the kiln causing serious issues of air pollution. Also, with the increase in the number of industries coming up, large amount of un-disposable waste gets accumulated. If suitable remedies are not adopted for its safe disposal, it may pollute the water bodies through runoff. This project is an effort to reduce the brick firing temperature in the kiln to about 600 °C thereby reducing the cost of production and making the whole process environmental friendly. This work will put forward a suitable alternative for the safe disposal of industrial debris like quarry dust and glass powder by incorporating them as a partial substitute for river sand which is one of the costly constituent of clay brick and thereby further reducing the cost of production. Experimental results showed higher compressive strength of 21.31 N/mm2when the brick was casted with mix proportion of Cement: Sand: Red earth: Glass Powder: Quarry Dust = 4:1:1:1.5:2.5. The strength measured at temperature 600 °C met the requirements of the National Standards.
Eleftherios Anastasiou, Michail Papachristoforou, Dimitrios Anesiadis
et al.
The waste produced from ready-mixed concrete (RMC) industries poses an environmental challenge regarding recycling. Three different waste products form RMC plants were investigated for use as recycled aggregates in construction applications. Crushed hardened concrete from test specimens of at least 40 MPa compressive strength (HR) and crushed hardened concrete from returned concrete (CR) were tested for their suitability as concrete aggregates and then used as fine and coarse aggregate in new concrete mixtures. In addition, cement sludge fines (CSF) originating from the washing of concrete trucks were tested for their properties as filler for construction applications. Then, CSF was used at 10% and 20% replacement rates as a cement replacement for mortar production and as an additive for soil stabilization. The results show that, although there is some reduction in the properties of the resulting concrete, both HR and CR can be considered good-quality recycled aggregates, especially when the coarse fraction is used. Furthermore, HR performs considerably better than CR both as coarse and as fine aggregate. CSF seems to be a fine material with good properties as a filler, provided that it is properly crushed and sieved through a 75 μm sieve.
Telma Ramos, Ana Mafalda Matos, Joana Sousa-Coutinho
Cork powder, the major waste from cork processing industries, is generated from grinding, cutting and finishing operations throughout the industrial cork process. Cork powder has been used mainly as fuel in cork industries. Cork waste ash is usually landfilled but if efficiently used in cement based construction materials it could contribute to sustainability. Strength and durability testing was undergone on mortar with 10 and 20% cement replacement with cork waste ash. Although strength is acceptable for 10% cement replacement with cork ash (5% loss at 90 days, compared to control), most durability properties (tested up to 6 months according to test type) reduced performance probably due to a broader pore structure caused by coarse particles in the ash which tested non pozzolanic. Moreover, cork waste ash does not present the necessary requirements in terms of chemical properties considering several standards. Present work has revealed that this cork waste cannot be used as a pozzolan or as a filler in cement based materials. In fact it is known that chemical composition of biomass ash is highly variable due to moisture variations, ash yield and different genetic types of inorganic matter in biomass and therefore it is important to pinpoint which types of biomass waste are adequate or not to use as cement replacement in construction.
Materials of engineering and construction. Mechanics of materials