Civil Construction Sector Research Articles

Long-Term Performance of Mortars with Combined Incorporation of Ladle Furnace Slag and Metakaolin

Ladle furnace slag (LFS) is used as a supplementary cementitious material (SCM) due to its high calcium oxide (CaO) content. Its binding properties are enhanced in the presence of siliceous materials, such as metakaolin (MK), forming a ternary mixture that can directly replace ordinary Portland cement (OPC). However, despite this blend having already been evaluated in alkali-activated mixtures, knowledge about this mixture in situations of direct replacement of OPC by slag is still lacking. This study evaluates the synergistic effects of combining LFS and MK in cementitious mortars. Due to an insufficient hydration reaction observed in the short term, this study focuses on assessing the long-term performance of these mortars. Both the fresh and hardened states at 28 and 180 days are evaluated, and the resulting microstructural characteristics and constituent phases are also examined. After 180 days of curing, the mortar with MK exhibits superior binding activity compared to the results at 28 days. Although the nominal resistance does not show a clear advantage with the application of MK, a significant reduction in the porosity of the mortar is observed. Microstructural analysis indicates that the addition of MK increases the hydration compounds when mixed with LFS. Importantly, the sample containing MK and LFS showed a 42% reduction in cement consumption, highlighting the potential for resource efficiency. Thus, this study contributes to promoting a circular economy between the steelmaking and civil construction sectors.

GESTÃO DE RESIDUOS NA CONSTRUÇÃO CIVIL

The present article intends to address the importance of the waste management plan in works, aiming at the optimization of material and human resources. The civil construction sector is a great vector of social and economic development of the country, but is responsible for the growing generation of waste in the country and its inadequate disposal has caused numerous problems, promoted by the large volume generated tied the difficulties of final disposal and the risks Arising from disposal in irregular deposits. These wastes are generally generated by companies and service providers of engineering, public agencies and construction contractors. The present work sought to collect information about the losses of the lack of an RCC management plan in any construction sector. After all the research, there is a need for practices to mitigate the numerous problems, as well as the need to improve the waste management plan, presenting ways for sustainable development, such as reuse and recycling. These practices have the objectives of generating a significant economic advantage over the final destination of the deposits, reducing the amount of raw material used and consequently the generation of waste, contributing to a more rational consumption of the raw material.

Production of ammonium nitrate for nitrogen recovery in a single bioreactor operating at pH 3

Ammonium nitrate (AN), i.e. NH4NO3, is extensively utilized in agricultural, mining, and civil construction sectors, with an annual production of approximately 16 million tons. Although the biological nitrification processes has been proven to be an important alternative to overcome the intensive energy consumption of the conventional chemical process for AN production, it necessitates ample chemical input for stable performance. This study marks the first demonstration of stable AN production from ammonium-rich wastewater employing a purely microbial-derived one-stage process, without the need for external chemical addition. This process functioned through an acidophilic ammonia-oxidizing bacteria (AOB), i.e., Candidatus (Ca.) Nitrosoglobus, which oxidized the ammonium in the feed to nitrite while simultaneously reducing the reactor pH to 3.2−3.4. Under these pH conditions, nitrite was chemically oxidized to nitrate with the provision of oxygen. Long-term bioreactor operation (>230 days) revealed consistent AN production from high ammonium wastewater at a nitrogen loading rate of 0.15 kg N/m3/d. Batch tests revealed that microbial ammonium oxidation was the rate-determining step in the overall AN production process. Further microbial enrichment and process optimization can enhance the microbial ammonium oxidation rate. In summary, the proposed acidic one-stage bioprocess presents a promising avenue for AN production from ammonium-rich wastewater.

Application of Waste Tire in Construction: A Road towards Sustainability and Circular Economy

The global demand for rubber is on a steady rise, which is driven by the increasing production of automobiles and the growing need for industrial, medical, and household products. This surge in demand has led to a significant increase in rubber waste, posing a major global environmental challenge. End-of-life tire (ELT) is a primary source of rubber waste, having significant environmental hazards due to its massive stockpiles. While landfilling is a low-cost and easy-to-implement solution, it is now largely prohibited due to environmental concerns. Recently, ELT rubber waste has received considerable attention for its potential applications in civil engineering and construction. These applications not only enhance sustainability but also foster a circular economy between ELT rubber waste with the civil engineering and construction sectors. This review article presents a general overview of the recent research progress and challenges in the civil engineering applications of ELT rubber waste. It also discusses commercially available recycled rubber-based construction materials, their properties, testing standards, and certification. To the best of the authors’ knowledge, this is the first time such a discussion on commercial products has been presented, especially for civil engineering applications.

Asphalt Mix Compressive Stress-Strain Behavior: An Analytical and Experimental Study of Variable Influence

To address the excessive depletion of natural resources in Indonesia's civil construction sector, there's a rising trend in utilizing plastic waste from packaging, such as beverage bottles and plastic bags, alongside renewable energy sources like Modified Buton Asphalt (MBA). MBA serves as a partial substitute for both fine and coarse natural aggregates and non-renewable energy sources like petroleum bitumen. This study aimed to investigate the effects of incorporating polyethylene terephthalate (PET) and polypropylene (PP) waste as partial substitutes for coarse and fine aggregates through experiments and t-tests. The objective was to determine how the stress-strain behavior of asphalt mixtures formed using MBA changed with the addition of this mixture. Additionally, compressive strength and elastic modulus were calculated under mixed compressive loads. PET and PP plastic waste replaced natural coarse and fine aggregates at three volume percentages: 1%, 2%, and 3%, with a PET:PP ratio of 50%. A manual grater was used to shred PET and PP plastic bottles into shredded plastic waste, which was retained in sieve no. 50 after sieving. The study found that adding PET, PP plastic, and MBA waste enhanced the asphalt mixture's mechanical strength and modified relevant variables, resulting in a more elastic and ductile behavior. Doi: 10.28991/CEJ-2024-010-05-011 Full Text: PDF

Carbon footprint in civil construction: literature review

We have Greenhouse Gases (GHG), which are highly harmful to the planet and responsible for contributing to the increase in global warming, as well as causing climate change. In view of the above, the aim of the paper was to develop a review of literature related to the environmental aspect, in an exploratory manner, through manuscripts obtained from an internet search platform, that is, articles published in indexed journals and scientific events associated with the theme. Carbon footprint in construction. Given the analyzed content, we have that (i) GHG are highly harmful to planet Earth, which are present in the atmosphere and are essentially formed by carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4), hexafluoride sulfur (SF6) and the two families called: perfluorocarbon (PFC) and hydrofluorocarbon (HFC), and (ii) that the civil construction sector is highly important (mainly due to the strengthening of the economy), due to the transcendent contribution provided to the mechanism's degradation of environmental quality, requiring mitigating actions to reduce this liability.

Gamification using technologies for occupational safety training in the civil construction sector.

Although regulatory norms on work safety offer guidelines for organizing and preventing accidents, the construction site is an environment susceptible to deviations, sometimes due to the lack of effective training. To this end, technologies such as virtual reality become possibilities for innovations with great advantages, as they allow simulations, modeling, exploratory environments and games, which allow the user to create a greater connection and interest in the subject in question. This study aimed to present the technological advances applied in safety-oriented training in the construction industry worldwide, emphasizing serious games through a systematic review of the literature. The review was carried out using five scientific databases, with a research protocol to answer questions about the application of gamification to guarantee the safety of workers. Fifteen articles were evaluated, with descriptive, observational research and case studies. It was found that the use of technologies in construction safety is not yet a common reality in the sector, as it presents challenges and limitations, such as gameplay and issues related to cost. However, they show great potential as a dynamic solution in the training of civil construction workers, effectively collaborating in accident prevention and work safety. Several software programs and applications were found for creating three-dimensional scenes and for providing users with a customized experience according to the needs observed in the virtual interaction; building information modeling tools, which promote realistic project modeling; and equipment to visualize the scenes created. Furthermore, the possibility of combining traditional theoretical teaching with serious games was verified. However, gamification applicability is an alternative that still has limitations, in addition to the lack of flexibility in the rules imposed on the game, hampering users' authenticity in making decisions.

Rheological enhancement of fresh polymer-modified cement composites via surface-modified graphene oxide

Polymer-modified cement (PMC) composites are extensively utilized in modern construction, especially in tunneling and structural applications, but their excessive flowability and reduced thixotropy continue to present fundamental rheological challenges. We present a novel approach to improving the rheological performance of PMC via surface-modified graphene oxide (GO), i.e., GOPMC composites. Specifically, the flow behavior of GOPMCs in relation to shear stress–shear strain response and apparent viscosity were investigated. The rheological parameters were analyzed by using Herschel–Bulkley's model. Additionally, zeta potential and dispersion analysis were conducted to investigate interparticle interaction forces. Flow measurement confirmed ∼20 % lower flowability of the GOPMC than the reference PMC. GOPMC composites further displayed higher yield stress of ∼82 % and ∼33 % reduced viscosity with inherent decreased shear-thickening compared to reference PMC composites. The yield stress of the GOPMC composite increased over time, disclosing distinct structural evolution linked to enhanced hydration kinetics by GO. Additionally, GO nanosheets in the GOPMC altered the rheopectic behavior of the redispersible polymer and enhanced the degree of thixotropy by ∼80 %, attributable to the promotion of bridged flocculated structures which produces a rigid system, facilitated by particle interaction forces comprising of van der Waals and steric forces. This latter observation provides a mechanistic framework for the enhanced rheological performance of GOPMC composites aiming at broader civil engineering and construction sector applications beyond tunneling.

Factors Affecting the Well-Being at Work and Risk Perception of Construction Workers: A Validated Interpretative Structural Modeling (VISM) Approach

Despite increased safety investments in the civil construction sector, high accident rates persist, often due to workers’ intentional unsafe behaviors influenced by poorly understood psychological factors. This study utilized validated interpretative structural modeling (VISM), an innovative technique, to investigate factors impacting the well-being and risk perception of construction workers in the Brazilian Amazon. The VISM model was developed through five steps: (1) identification of indicators; (2) definition of constructs; (3) identification of relationships between constructs; (4) validation of these relationships; and (5) creation of the model. The results underscore the effectiveness of VISM in crafting complex models with robust statistical validity, even in studies with sample limitations and intricate or circular relationships among constructs. The research identified various factors in this phenomenon, such as the importance given by management to workplace safety, job dissatisfaction, work-related stress, turnover intention, work–family balance, alcohol and cigarette use, physical health, perception of accident risks at work, and education and training in workplace safety. Another significant contribution lies in the model’s ability to discern both direct and indirect relationships among these well-being factors. This insight enables the formulation of strategies to enhance worker well-being and reduce workplace accidents, particularly those stemming from intentional unsafe behaviors.

Civil construction in Angola: planning aspects in post-war management

This study seeks to answer in full, what is the influence of the civil construction sector for the development process of Angola, a country on the African continent, which has a history of 27 years of armed conflict. Thus, it is proposed to analyze the sector in question, aiming at the aspects and management plans of the post-war period, from 2002 to 2022, in order to statistically measure its contribution to the country's growth. In this perspective, in order to present facts and influence of the sector, it is necessary the factors that did not support the development structure, but that contributed and/or contribute significantly to the degradation of the nation. To achieve this objective, qualitative and quantitative methodological approaches were used, allowing the understanding and simplified exposition of the complex information obtained through bibliographic references, and analyzing the data obtained through different sources. As a result, some planned programs were executed and continue to be, but do not meet the demand and we conclude that Angola, in its 18 provinces, however does not promote the great measure of reconstruction, with little efficiency in the civil construction process.

Seeking the Optimisation of Public Infrastructure Procurement with NEC4 ECC: A Peruvian Case Study

The modern civil engineering and construction sector requires collaborative work environments, learning and trust among all parties involved, qualities that are absent in the Peruvian reality. This study, which is based on an extensive literature review, investigates this challenge. The study reflects upon (i) the current situation of public works procurement in Peru and (ii) the New Engineering Contract (NEC), which has recently been implemented in Peruvian Special Public Infrastructure Projects. Comparisons are presented between the characteristics, documentation and roles of these two systems, with the purpose of understanding and representing the advantages, disadvantages and possibilities of integrating the good contractual management practices of the NEC4 Engineering and Construction Contract into the traditional Peruvian State Contracting Law (Ley de Contrataciones del Estado: LCE). The research is validated through the case study of a high-impact road infrastructure project in the city of Arequipa, Peru, which revealed five main deficiencies from Peruvian procurement processes which hinder good contractual management and, also, facilitated an initial assessment of the challenges and improvement opportunities in public infrastructure procurement. Thus, a contribution is made to closing the knowledge gap regarding the implementation of the NEC4 ECC in public sector works.

Environmental, social and governance (ESG) and innovation in the construction sector: Systematic Literature Review

Purpose – To analyze the evolution of Environmental, Social and Governance (ESG) and innovation in the civil construction industry, focusing on innovative and sustainable practices, as well as ways of measuring the level of construction companies in these themes. Design/methodology/approach – A Systematic Literature Review approach was used. The Web of Science and Elsevier Scopus Databases, from 2017 to 2022, were used for data collection, based on a set of keywords and Boolean operators ("sustainable development" & "framework" & "measurement" & "environment”). Using the Zotero Software, 488 papers were classified and organized according to the publication date, main content, proposals for sustainable and innovative tools and techniques. The papers were analyzed in the VOSviewer Software. Findings – There is an Asian predominance in the volume of publications and networks of strong connections in clusters by countries. The authors tend to look for papers from the same region as a reference, going against the concept of globalization of ESG and innovation themes and the condition of replicability of practices. Among the exemplified practices, there are replicable models and initiatives, as well as incipient innovative construction materials and methods in search of consolidation. Originality/value – Amid the current and growing discussion about innovation and ESG in organizations, it is noted that the civil construction sector still lacks better performances in these themes. This paper aims to contribute to the advancement of the discussion in the sector, bringing together works found in recent literature.

The effect of temperature on corn straw ash production as supplementary cementitious material

The civil construction sector is growing, which is of great socioeconomic importance. However, this increase has consequences that are already the focus of studies for many researchers. One of the main materials used in civil construction, cement, is responsible for a significant amount of carbon dioxide (CO2) emissions. Cement production alone has been responsible for approximately 8% of global CO2 emissions, primarily due to its high level of embodied carbon in cement factories (Blois; Lay-Ekuakille, 2021; Cadavid-Giraldo; Velez-Gallego; Restrepo-Boland, 2020 e Un Environment and International Energy Agency, 2017). Most of the CO2 emissions come from burning the clinker used to produce this filler, along with the significant energy consumption required for this process. Cement factories, in addition to this, are responsible for the rapid consumption and depletion of limited resources.

The Acceptance of Smart Home Technologies

The advancement of home automation technologies allowed the integration of systems for smart home implementation in the civil construction sector. However, the smart home's dissemination depends on factors that can enhance or hinder users' acceptance of smart home technologies. The article aims to identify the benefits and barriers users perceive that can interfere with implementing smart home technologies. The methodology utilized a systematic literature review using 122 articles in journals indexed in Scopus, Web of Science, Science Direct, IEEE, and Scielo scientific databases to gather barriers and benefits to smart home implementation. The literature mentions the benefits in the environmental, financial, and psychological categories as the main factors that potentiate the dissemination of smart home technologies. On the other hand, the barriers classified into the technological, ethical, and human categories have the major effect of hindering smart home implementation.

INDICADORES DE AVALIAÇÃO DA SUSTENTABILIDADE NA CONSTRUÇÃO CIVIL

In view of the new perspectives brought about by the concept of sustainable development, the need was created for the restructuring of companies and adaptation to this new perception. In the civil construc-tion (CC), the challenge of sustainability, assumed a few years ago, a prominent role in the Brazilian agenda. Based on this and the background of different authors, the objective of this article was to deve-lop a methodology that considers the multiple existing indicators to diagnose companies in the CC sector in relation to the implementation of sustainable practices. For this purpose, a matrix with more than 150 indicators and 38 authors was created, which developed their studies about this problem, and could serve as a positive benchmarking for organizations that wish to build their own performance indicators.

Towards Sustainable Construction: A Systematic Review of Circular Economy Strategies and Ecodesign in the Built Environment

This review discusses the unsustainable nature of current production and consumption patterns, particularly in the civil construction sector. To address this, the circular economy model has been proposed as a solution, but the impact reduction of circular strategies (CS) is not well understood. Thus, aligning CS with ecodesign can help achieve sustainable development. We conducted a systematic review of studies on CS and ecodesign strategies (ES) in the built environment, which led us to identify 23 essential strategies, including reuse, recycling, design for disassembly, and design for life extension. This article expands on previous research by identifying 51 CS and ES, some of which are interconnected, and adopting one strategy may benefit another. The authors propose a framework based on the Plan-Do-Check-Act concept to support and manage trade-offs when selecting strategies and to facilitate a collaborative decision-making process. The framework can also help manage the effects of using these strategies on circularity and environmental, social, and economic performance, ultimately improving the construction sector’s environmental performance.

Estimating the Importance of Civil Construction for the Brazilian Economy Through Hypothetical Extraction of the Input-Output Matrix

This paper aims to undertake a systemic analysis of civil construction to verify whether public investments made from 2007 onwards were able to increase the sector's productive linkages in the Brazilian economy. For this, the hypothetical extraction method of the input-output matrix and the official matrices of the country from 2005 and 2015 are used. The results show that the importance of the productive structure of the construction sector - total extraction - exceeds 7.42% of GDP in 2005 to 10.06% in 2015. This fact reveals that the civil construction sector in 2005 was the seventh most important moving to the fourth in 2015 in a total of twelve sectors considered. Another important finding lies in the fact that despite the construction sector presenting an increase in the complexity of its productive structure, it showed strong backward linkage, but low forward linkage, in both analyzed periods. Through these results, it is possible to conclude that the tax exemption of some inputs, reduction of real estate interest, expansion of credit for housing through public housing and infrastructure policies may have been essential for the increase in the complexity of the sector's productive chains between the years' from 2005 and 2015. Such findings are useful for the scientific literature that investigates the sector by bringing evidence to Brazil and to policymakers given that possibly the construction sector can be used as a strategy to promote and stimulate economic activity in times of crisis.

Theoretical and Experimental Strategy for the Control and Mitigation of Efflorescence in Metakaolin-Based Geopolymer

Compared with portland-cement-based matrices, the high mechanical strength, satisfactory durability, and sustainable features of geopolymeric matrices have brought great interest in the civil construction sector. Excessive activator content in a geopolymer mixture can cause efflorescence, a phenomenon related to the unreacted alkalis that compromise the mechanical properties and aesthetics of the structures. This article proposes applying statistical mixture design (SMD), associated with simultaneous optimization for the dosage of geopolymeric matrices, to evaluate and mitigate efflorescence. Based on the extreme vertices screening design, the formulations were made using metakaolin as a precursor, NaOH and sodium silicate as the activator, and sand and superplasticizer. The formulation with the lowest efflorescence formation, highest compressive strength, and adequate workability was the one whose molarity of NaOH was equal to 9.02 M, and the ratios Na2O/Al2O3, SiO2/Al2O3, and H2O/Na2O were equivalent to 1.43, 2.65, and 8.36, respectively. In addition, the Na2O/Al2O3 ratio was the predominant factor for efflorescence occurrence. SMD associated with simultaneous optimization is a technically viable alternative for minimizing free sodium in geopolymeric matrices.

ENVIRONMENTAL MANAGEMENT AND SUSTAINABLE DEVELOPMENT IN THE CIVIL CONSTRUCTION SECTOR

The civil construction sector is, historically, extremely important for the economy of a country, especially Brazil. This reality is even more intensified in the pandemic scenario, where COVID-19 negatively impacted various sectors of the economy, especially those related to non-essential activities. The general objective of the article presented here is to discuss how environmental management and the effective management of resources can enable a process of sustainability in modern organizations, especially those that work in the civil construction sector. The methodology is descriptive and qualitative and can be classified as a bibliographical research.

Construction Industry and Its Contributions to Achieving the SDGs Proposed by the UN: An Analysis of Sustainable Practices

This research aimed to analyze the perceptions of professionals in the construction sector operating in Brazil regarding the development of sustainability practices in the sector and their contributions to achieving the United Nations Sustainable Development Goals (SDGs). To this end, a literature review was developed, a survey was conducted among industry professionals, and the collected data were treated using Cronbach’s alpha, hierarchical cluster analysis, and the TOPSIS multicriteria method. As a result, considering the generated ranking, the practices determining the promotion of a more sustainable construction sector were the encouragement and promotion of sustainability-focused events, education on sustainability, water treatment, and community project development. From the perspective of contributions to achieving the UN SDGs, greater alignment of sustainable practices with the established goals was highlighted in SDG 1, which seeks to eradicate poverty; SDG 4, which promotes inclusive education; SDG 6, referring to the importance of water treatment and access for all; SDG 7, which aims to ensure access to clean and affordable energy; SDG 9, which proposes the development of resilient, inclusive, and sustainable infrastructure; SDG 11, which advocates for sustainable cities and communities; and SDG 12, which proposes the adoption of more sustainable production and consumption patterns. It is believed that this research represents the first exploratory study to consider sustainable practices in the civil construction sector, which are aligned with the sustainable development objectives proposed by the UN and consider the context of a country with an emerging economy from the perspective of professionals working in the sector.