Materials In Construction Industry Research Articles

Influence of TiC Particles on Mechanical and Tribological Characteristics of Advanced Aluminium Matrix Composites Fabricated through Ultrasonic-Assisted Stir Casting

The present investigation highlights the development of high-performance materials in the construction materials industry, with a special focus on the production of aluminium matrix composites (AMCs) containing titanium carbide (TiC) particles. The stir casting method with ultrasonic assistance was employed to enhance the mechanical and tribological properties. ASTM standards were employed to evaluate the influence of TiC particles on density, hardness (VHN), ultimate tensile strength (UTS), and wear resistance at various TiC weight fraction percentages (0.0 wt.%, 2.0 wt.%, 4.0 wt.%, 6.0 wt.%, and 8.0 wt.%). Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analysis were performed to analyse the microstructural changes and elemental phases present in the synthesised composite. Results revealed that the incorporation of 8 wt.% TiC reinforcement in the metal matrix composites demonstrated significant improvements compared to the base alloy. In particular, a substantial enhancement in hardness by 32%, a notable increase of 68% in UTS, and a significant 80% rise in yield strength were observed when contrasted with the pure aluminium alloy. The tensile fracture analysis of the specimens revealed the presence of dimples, voids, and cracks, suggesting a brittle nature. To assess the wear characteristics of the composites, dry sliding wear experiments were performed using a pin-on-disc wear tester. Incorporation of TiC particles resulted in a lower coefficient of friction than the base alloy, with the lowest friction coefficient being recorded at 0.266 for 6 wt.% TiC, according to the data. FESEM and energy-dispersive X-ray spectroscopy (EDXS) were used to examine the surfaces of the worn pin. Overall, the inclusion of TiC reinforcement particles in the matrix alloy greatly enhanced the wear resistance and friction coefficient of the Al-6TiC composites. Ploughing and adhesion under lower loads and delamination under higher loads were the wear mechanisms observed in the wear test.

Impact of Sulfate in the Sand on the Compressive Strength of Metakaolin-Based Geopolymer Mortar

The advancement of cement alternatives in the construction materials industry is fundamental to sustainable development. Geopolymer is the optimal substitute for ordinary Portland cement, which produces 80% less CO2 emissions than ordinary Portland cement. Metakaolin was used as one of the raw materials in the geopolymerization process. This research examines the influence of three different percentages of sulfate (0.00038, 1.532, and 16.24) % in sand per molarity of NaOH on the compressive strength of metakaolin-based geopolymer mortar (MK-GPM). Samples were prepared with two different molarities (8M and 12M) and cured at room temperature. The best compressive strength value (56.98MPa) was recorded with 12M with lower sulfate content (0.00038%) at 28 days. Also, an inverse relationship is recorded between the increasing sulfate percentages in the sand and the compressive strength values of (MK-GPM). A higher reduction in the compressive strength results at 28 days (60.88% per 8M/NaOH) and (62.23% per 12M/NaOH) was associated with a higher percentage of SO3 in the sand (16.24%).

Behaviour of autoclaved magnesium oxysulfate cement pastes

This study investigates the influence of autoclave curing on Magnesium Oxysulfate Cement cement compared to acid addition effects, especially on microstructure and mechanical properties. For this purpose, compressive and flexural strength, water resistance and volume stability were analysed. In addition, X-ray diffraction and Scanning Electron Microscopy were applied to verify the phase composition and microstructure of these matrices. Results indicate that the autoclave process affects the mechanical properties. The increase in the molar ratio reduces flexural strength and slightly increases the compressive strength. The autoclave also reduces water resistance, especially with increasing curing time. Longer autoclaving time (4 h) increases expansion in the pastes, which stabilize in around 30 days. In the microstructure, autoclaving reduces or inhibits the formation of the 517 phase, which is responsible for increased mechanical strength, and provides the formation of the Mg(OH)2 and 512 or 513 phase. Thus, in MOS cement, the autoclave process mainly promotes the formation of 512 or 513 phases. Therefore, the material can be improved to be submitted to curing in an autoclave and present an increase in mechanical properties, which will provide the large-scale production of lightweight boards in the construction materials industry and may influence the increase in the use of this material in construction.

Exploring Business Leadership in a Start-up Active in the Construction Materials Industry

Abstract The scope of the article is to identify the leadership importance and the impact that it has on a small start-up company active in the construction materials industry. Being a small organization and at the beginning of the journey, the challenges that leaders and subordinates face are diverse and of significant importance. The literature review studied in-depth revealed to us that leadership styles and the organization in which they are applied have major importance in business development and creating common objectives. The methodology used was qualitative, interviewing all the employees of the selected start-up, based on questions to reveal the perception of the employee regarding leadership in their organization. In conclusion, the research reveals that in a young start-up, leadership is very important, and the leader must communicate with the followers; motivate, influence, and help them to develop. This study focuses on critically exploring, analyzing, and understanding the implications that different leadership styles have over a start-up company active in the construction materials industry. This case study emphasizes consistent and relevant findings regarding the role of leadership characteristics and their implications on a small organization, in a quest of understanding if different approaches adopted by leaders may facilitate follower engagement that will drive organizational goals and performance. The research method is presented, consisting of a qualitative approach, with the use of interviews performed with all the employees of the selected start-up. Throughout the report, critical judgment is endorsed by relevant literature. Based on the collected responses, findings supported a strong correlation between the dominant form of leadership style and the effects on employees’ responsiveness that is further shaping organizational achievements.

Decarbonizing the lime-based construction materials industry: A practical guide for cradle-to-gate life-cycle inventory

This paper presents an integral parametrized framework to calculate the life-cycle inventory (LCI) in lime-based construction materials manufacturing, utilized for implementing decarbonization strategies in the LCI. The calcination operation is identified as the main source of CO2 emissions, with 0.79 tCO2/t CaO being inevitable (65 % of total emissions). Kiln fuel combustion contributes up to 35 % to emissions. Decarbonization strategies are ranked as: carbon capture, carbon direct avoidance, and circular economy. Parallel Flow Regenerative Kilns result in 40 % lower energy consumption compared to Long Rotary Kilns. Substituting lignite with natural gas can reduce emissions by up to 17 %. Direct CO2 separation from calcite decomposition, coupled with thermal energy recovery, can capture 65 % of the CO2 emitted, reducing kiln energy consumption by 15 % and CO2 emissions from fuel combustion by 13 %. The high purity of captured CO2 offers potential for future use as a valuable by-product. Supplementary raw materials in lime-based binder production have limited effects on CO2 emissions due to unavoidable emissions from calcite decomposition. The proposed process-oriented parametric methodology empowers Life Cycle Assessment practitioners, reducing reliance on generic databases for rigorous and transparent inventory calculations.

Einflüsse von Kreislaufwirtschaftsmaßnahmen auf Ressourcennutzung und Dekarbonisierung in der Stahl- und Zementindustrie

ZusammenfassungEine verstärkte Kreislaufwirtschaft ist eine von mehreren Maßnahmen zur Dekarbonisierung industrieller Produktionsprozesse. Insbesondere die energieintensive Grundstoffindustrie hat in der Schließung von Stoffkreisläufen erhebliche Potenziale zur Reduktion von Treibhausgas-Emissionen und Steigerung der Ressourceneffizienz. Eine Analyse des Status Quo zeigt, dass die österreichische Eisen- und Stahlindustrie sowie die Zementindustrie bereits Vorreiter in Kreislaufwirtschaft und der emissionsarmen Produktion in Europa sind. In diesem Artikel werden weitere Potenziale aufgezeigt und insbesondere branchenübergreifende Ansätze zum Schließen von Stoffkreisläufen betrachtet.

Study of metakaolin geopolymer composites reinforced by clean broom-like bristle bamboo fibers

Natural fiber-reinforced geopolymer (GP) is gaining popularity in the construction and building materials industries due to its natural renewability, accessibility, low cost, and excellent mechanical properties. In light of this, an investigation was conducted on the effect of bamboo fiber (BF) loading and fiber pretreatment methods on final composites. Mechanical tests showed that compared to pure GP, the compressive strength and flexural strength of GP composites were slightly negatively affected by the addition of either untreated or alkali-treated BFs. However, the loading of KH550 significantly improved the mechanical properties of GP with the addition of alkali-treated BFs more than untreated BFs. Scanning electron microscopy (SEM) analysis illustrated that the employment of KH550 effectively improved the interfacial performance between the BF and GP matrix. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) tests demonstrated the successful synthesis of GP and that the addition of KH550 had little effect on the main crystal structure and chemical composition of GP. This study provides a new method of bamboo fiber preparation and the feasibility of applying it to reinforce GP.

Experimental Analysis of Lightweight Fire-Rated Board on Fire Resistance, Mechanical, and Acoustic Properties

Using lightweight fire-rated board (LFRB) presents cost-effective opportunities for various passive fire protection measures. The aim of the project is to develop an LFRB with enhanced fire resistance, acoustic properties, and mechanical properties. These properties were determined using a Bunsen burner, furnace, energy-dispersive X-ray, impedance tube instrument, and Instron universal testing machine. To fabricate the LFRBs, vermiculite and perlite were blended with flame-retardant binders, and four types of LFRBs were produced. A fire test was conducted to compare the fire-resistance performance of the LFRBs with a commercially available flame-retardant board. The B2 prototype showed exceptional fire-resistant properties, with a temperature reduction of up to 73.0 °C, as compared to the commercially available fire-rated magnesium board. Incorporating nano chicken eggshell into the specially formulated flame-retardant binder preserved the LFRBs’ structural integrity, enabling them to withstand fire for up to 120 min with an equilibrium temperature of 92.6 °C. This approach also provided an absorption coefficient of α = 2.0, a high flexural strength of 3.54 MPa, and effective flame-retardancy properties with a low oxygen/carbon ratio of 2.60. These results make the LFRBs valuable for passive fire protection applications in the construction and building materials industry.

What are the key factors of enterprises' greenwashing behaviors under multi-agent interaction? A grey-DEMATEL analysis from Chinese construction materials enterprises

PurposeThe surging market demand for green construction materials has brought opportunities for construction materials enterprises' greenwashing behavior (GWB). This study aims to establish the causal relationship among the influencing factors of GWB and reveal the key influencing factors from the perspective of Chinese construction materials enterprises under multi-agent interactions.Design/methodology/approachThis study is based on stakeholder theory, resource-based theory and the green development behavior and performance of industrial enterprises (GDBP-IE). First, with the literature analysis, an index framework of the influencing factors of enterprises' GWB was constructed from five dimensions (including 15 factors): environmental regulation, public scrutiny, market environment, corporate resources and corporate green development (GD) performance. Second, the interactive relationship among influencing factors was obtained by a questionnaire survey. Finally, the data are processed and analyzed with the grey-DEMATEL (Decision-making Trial and Evaluation Laboratory) method.FindingsAmong the factors, corporate information transparency has the greatest impact on the other factors, and consumer green preferences are most influenced by others. The most critical and important factor is the corporate social performance factor. In China, corporate social performance, corporate information transparency, corporate size and media supervision are the key factors influencing the GWB of construction materials enterprises.Originality/valueThis study provides a new perspective on the literature related to GWB by considering multi-agent interactions and extends the evidence from the construction materials industry for research on the drivers or influencing factors of enterprises' bad environmental behavior. Furthermore, it adds insights from China for further research on the governance strategies of GWB in other countries.

Use of Foundry Sands in the Production of Ceramic and Geopolymers for Sustainable Construction Materials

The aim of this research was to evaluate the possibility of reusing waste foundry sands derived from the production of cast iron as a secondary raw material for the production of building materials obtained both by high-temperature (ceramic tiles and bricks) and room-temperature (binders such as geopolymers) consolidation. This approach can reduce the current demand for quarry sand and/or aluminosilicate precursors from the construction materials industries. Samples for porcelain stoneware and bricks were produced, replacing the standard sand contained in the mixtures with waste foundry sand in percentages of 10%, 50%, and 100% by weight. For geopolymers, the sand was used as a substitution for metakaolin (30, 50, 70 wt%) as an aluminosilicate precursor rather than as an aggregate to obtain geopolymer pastes. Ceramic samples obtained using waste foundry sand were characterized by tests for linear shrinkage, water absorption, and colorimetry. Geopolymers formulations, produced with a Si/Al ratio of 1.8 and Na/Al = 1, were characterized to evaluate their chemical stability through measurements of pH and ionic conductivity, integrity in water, compressive strength, and microstructural analysis. The results show that the addition of foundry sand up to 50% did not significantly affect the chemical-physical properties of the ceramic materials. However, for geopolymers, acceptable levels of chemical stability and mechanical strength were only achieved when using samples made with 30% foundry sand as a replacement for metakaolin.

Impact resistance-compressive strength relationship of steel fiber-reinforced concrete at ambient and high temperatures

Despite the great scientific developments in fire resistance technologies and construction materials industry, fires threaten human lives and negatively impact the economy every day. One of the possible scenarios when a structure is subjected to accidental fire is the fragmenting of structural elements or falling of heavy objects from higher stories on fired concrete elements, which imposes a dual accidental loading. The aim of this research is to spotlight the relationship between the compressive strength and impact energy of concrete subjected to the dual action of high temperatures and repeated impacts. Cube and disk specimens from three mixtures with 0 %, 0.5 %, and 1.0 % of steel fibers were cast to investigate the compressive strength and repeated impact strength, respectively. Groups of specimens from each mixture were subjected to temperatures of 200 °C, 400 °C, and 600 °C in addition to the reference unheated specimens. The results showed that compressive strength and impact energy behave differently under the effect of high temperatures. However, regardless of the exposure temperature, the impact energy increases with the increase of compressive strength. This increase is more evident for failure impact energy compared to cracking impact energy. Simple linear and second order formulas were found suitable to describe these relations with R2values ranging from 0.71 to 0.96.

Empirical Analysis of Operating Results of Listed Companies Under the Multiple Regression Model Standard—Based on the Data Verification of China’s 2022 Real Estate A-Share Financial Interim Report

The real estate economy is also a commodity economy, the proper development of the real estate economy is conducive to improve the national tax revenue and promote the people’s employment and entrepreneurship, which can achieve the sustained and stable growth of the national economy. The real estate economy is not only related to the construction and building materials industries, but also closely related to many real industries. It has the basic role of leveraging the common circular development of various industries. For example, furniture and household appliances, kitchenware, grocery retail, sports and tourism, art education and other industries can be developed on the basis of the real estate industry. In the process of the rapid development of real estate, various problems will gradually appear. Based on the analysis of 2022 and 2021 interim financial reports, this paper uses multiple regression model to find out the factors that affect the profitability of real estate enterprises, and proposes measures to improve the profitability of real estate enterprises based on the analysis results.

Improving flotation decarbonization efficiency of coal gasification fly ash by mechanically breaking pore: An experimental and molecular dynamics simulation study

The high unburned carbon content of solid waste coal gasification fly ash is the main reason that it cannot be used in the construction material industry, which leads to serious waste of resources and environmental pollution. Currently, decarburization flotation has been a dominating method for coal gasification fly ash resource utilization. However, the flotation process has low efficiency and high reagent consumption because of the rich surface porosity of unburned carbon. Herein, we innovatively developed a mechanical grinding strategy to break the pore distribution on the surface of unburned carbon, significantly reducing the pore size, increasing hydrophobic functional groups and improving the flotation efficiency. The removal rate of unburned carbon is more than 95% in flotation tailings with a mechanical grinding intensity of 120 rpm and grinding time of 30 min. Furthermore, the adsorption of water on porous unburned carbon surface was studied by molecular dynamics simulation for the first time, and the results show that decreasing the particle surface porosity of unburned carbon can accelerate the diffusion rate of water molecules on the unburned carbon surface, improve the wettability of the particle surface and increase the adhesion probability between the unburned carbon particles and bubbles and remarkably improve the its floatability. This work is the first application of mechanically breaking pore to the flotation separation of unburned carbon and ash from coal gasification fly ash and provides valuable inspiration for the design of porous particles flotation, not limited to the separation of gasification fly ash.

THE INFLUENCE OF INSTAGRAM SOCIAL MEDIA MARKETING AND TECHNOLOGY READINESS TO INCREASE PURCHASE INTENTION THROUGH SOCIAL MEDIA BRAND ENGAGEMENT MEDIATION ON X INSTANT MORTAR BRAND

The Covid-19 has disrupted several businesses marketing strategies. This also has an effect on the building materials industry, they have to adapting its marketing to the B2C market via social media. Social Media Marketing can increase a customer's interest in making purchase, according to the findings of prior study and theory; yet, the company's data reveals various outcomes. There was a strong response to the social media marketing campaign, however the number of sales was not related to the number of sales the company made. Consequently, this study will assess the impact of Social Media Marketing on Purchase Intention as mediated by Social Media Brand Engagement, and considering the Technology Readiness. 150 Instagram followers of Mortar Instant X were surveyed using a quantitative way to acquire data for this study. According to the findings, Social Media Marketing has a positive direct and indirect influence (mediated by Social Media Brand Engagement) on Purchase Intention. Meanwhile, Technology Readiness has a positive direct and indirect effect (mediated by Social Media Brand Engagement) on Purchase Intention. It is anticipated that Instant Mortar X and the construction materials industry would use the findings of this study to develop and implement social media marketing strategies.

Upcycling waste plastics to fabricate lightweight, waterproof, and carbonation resistant cementitious materials with polymer-nano silica hybrids

Most of the plastic waste, that rapidly and massively accumulates in the environment, does not get recycled but ends up in landfills and oceans causing pollution of water, soil, and air. This work presents an enhanced recycling scheme of waste plastics as aggregates in cementitious materials with ethylene-vinyl acetate (EVA) and nanosilica (nS) hybrids. 10% and 15% of natural sand were replaced by recycled waste plastic (RWP), and density, mechanical properties, capillary sorptivity and carbonation resistance of the RWP cementitious materials were evaluated. Results showed that not only the fabricated RWP specimens were 15%–18% lighter than the reference mixture but also the hybrid effect of EVA-nS was efficient in mitigating mechanical strength reductions and improving ductility up to 107%. Significant ameliorations of around 50% were observed in waterproof performance owing to the polymeric films created by EVA, while over 70% increase in carbonation resistance was noted owing to the filling and pozzolanic effects of nS. The replacement of natural sand with RWP by 10% would have the potential of reducing the annual sand consumption by 0.56–1 billion tons, which would substantially decrease the global CO2 emissions by 2.8–13.9 million tons annually. These findings pave a green path for upcycling RWPs in the sustainable, durable and lightweight construction material industry.

METHODOLOGY FOR ASSESMENT OF EXTERNAL FACTORS AFFECTING THE FINANCIAL SECURITY OF BUILDING MATERIALS INDUSTRY ENTERPRISES

This article analyzes the external factors affecting the financial security of construction materials industry enterprises and reveals the specific features of the construction industry in ensuring financial security at the micro level. The author has thoroughly analyzed the world's existing methodology for assessing the financial security of the enterprise. Taking into account that the method of determining the level of financial security of the enterprise based on the assessment of the internal and external environment is universal, it can be used in construction industry enterprises, taking into account the specific characteristics of the construction industry network.

Carbon Emission of Construction Materials and Reduction Strategy: Take Prefabricated Construction in China as an example

The rapid development of urbanization has made the building industry gradually become a major industry of carbon emissions. Now that the goal of carbon neutrality is increasingly clear, the construction industry will face a very serious challenge of energy conservation and emission reduction. Especially in developing countries, such as China, to achieve carbon neutrality, the government pay more attention to emission reduction and environmental protection in the construction materials industry. This paper first analyzes the carbon emissions of three common building materials: cement, steel, and asphalt. The production of one ton of cement will produce about 659 kg of CO2; the production of 1 ton of crude steel will produce more than 2,000 kg CO2, and the construction of a 20 km long road will produce more than 50 million kg of CO2. To achieve carbon emission reduction in the construction process and alleviate the pressure on the environment, prefabricated buildings are an important carbon reduction strategy. Compared to on-site construction, prefabricated constructions use less resources and release less carbon dioxide. However, prefabricated construction technology is not the mainstream of the construction domain yet in China. The paper analyzes the factors of the growth of prefabricated construction from three aspects: society and government, market, and technology.

Features of the innovation construction materials design at the current stage of the industry development

Introduction. The problem of the development, mass production and introduction of the innovation construction materials is especially relevant in the conditions, when whole economy of Russia is aimed at the innovative development and import substitution as well.
 
 Materials and methods. The system approach, the method of scientific synthesis, methods of statistic and comparative analysis, the historical method were used during this research. Works of domestic and foreign scientists, regulatory legal acts and strategic documents in the field of production of construction materials, sources from periodicals, data of Federal State Statistics Service, statistical bases of foreign countries, data of the Committee of the Russian Union of builders on the development of the construction materials industry, National consolidation of builders (NOSTROY), Rating Agency of the Construction Complex (RACC), as well as some information, provided by producers of construction materials, acted as the materials for the research.
 
 Results. The author studied the nature of the innovation construction materials, defining the specifics of their development and introduction, such as experimental nature, availability of numerous options of the product, high project cost, long term and high project risk. The term “product design” is considered in the confined and extended sense. It is proved, that design is not limited to detailed design when developing the innovation construction material. Some elements of design have to take place at other stages of the product development as well.
 
 Conclusions. A new paradigm of the innovation construction materials design, considering the matter comprehensively (in terms of achievement of the necessary, improved properties of new material, demand the market, profit maximizations from its production and introduction, reliability, environmental friendliness, etc.) is required in modern conditions. As the result of the research the author developed the cross-disciplinary hierarchical structure of the innovation construction material design, uniting many tasks relating to the functions of management, marketing, research and design, production, finance and covering all the phases of the construction materials development.

Contributions of cleaner production and end-of-pipe treatment to NOx emissions and intensity reductions in China, 1997–2018

The Chinese experience of economic development and environmental protection provides an important reference for developing countries. Although changes in aggregate NOx emissions have been widely studied, there is a relative lack of studies analysing NOx intensity changes and their related development strategies in China. This study attempts to identify the socioeconomic drivers and change patterns for both NOx emissions and intensity considering the cleaner production and end-of-pipe treatments. Both structural decomposition analysis and structural path analysis were used to analyse the NOx emissions/intensity changes at different levels and transmission layers in China in the last two decades (1997–2018). The results indicate that construction contributes the most to NOx emissions/intensity, followed by transportation. The emission intensity effect is the primary driver of NOx emissions/intensity reduction, which mainly benefits from end-of-pipe treatment and energy efficiency improvement. Especially, during 2012–2018, they decreased 11,916 Kt-NOx and 8,103 Kt-NOx emissions and aggregate embodied intensity by 43.2% and 29.8%, respectively. The final demand effect is the primary deterrent, which is attributed to investment and consumption effects. The critical sectors for future NOx reduction are the construction and building materials industry, transportation and other services industry. The policy implications and recommendations for the future developments are discussed based on the study findings.

Fabrication and Characterization of Cement-Based Hybrid Concrete Containing Coir Fiber for Advancing Concrete Construction

Nowadays, the incorporation of natural fiber, such as coir fiber, to high-strength concrete has sparked a lot of attention in the construction materials industry. This is because coir fibers are significantly cheaper and more widely accessible than synthetic fibers. Natural fibers such as bamboo, flax, hemp, and coir have distinct microstructures and chemical compositions from cement-based materials. The physical and mechanical properties of natural fiber, such as coir fiber, are significantly correlated with fiber concentration and cellulose component. However, coir fiber has high stretching to failure, while bamboo, flax, and hemp fibers are very resistant to stress and increase stiffness. Based on these distinctive fiber qualities, it is anticipated that coir fiber would facilitate the development of cement-based materials for advanced concrete building applications. In this paper, coir fiber-reinforced cement-based concretes were evaluated in terms of workability, compressive strength, flexural strength, splitting tensile strength, modulus of elasticity, and permeability. The relationship between strength and fiber content was analyzed to understand the impact of coir fiber on the properties of coir fiber-reinforced cement-based concrete. Based on the results obtained, it is determined that 2% coir fiber modification offers the highest compressive strength, splitting tensile strength, and flexural strength. Moreover, the modulus of elasticity is increased, and the permeability is plummeted by the volume fractions of coir fiber 1%, 2%, and 3% because the blending of coir fiber has a bridging and dispersing mechanism of the force-carrying capacity in concrete. In conclusion, coir fiber might be a viable choice for improving the strength and durability of concrete. Therefore, the sparing use of coir fiber presented in this research can be implemented for the manufacturing of concrete in the future.