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The present research examines a wide range of civil engineering projects across India, each providing a distinct platform for investigating quality management, automation techniques, and improvement activities using artificial intelligence (AI) techniques. The study covers projects demonstrating the variety of India’s civil engineering undertakings, from the Smart City Mission to the Mumbai Metro Line 3 and the Chennai-Madurai Expressway. The adoption of quality management techniques, including ISO 9001 Certification, Lean Construction, Six Sigma, Building Information Modeling (BIM), and Total Quality Management (TQM), is evaluated in the projects. In this case study, experimental datasets and employed AI techniques such as Artificial Neural Networks (ANN) are used to predict accurate outcomes. It was also observed that more variation in the regression coefficient (R2) and errors (MSE) from 1 to 5 hidden layer nodes. While hidden layer nodes 6 to 10 performed stable outcomes. Out of them, hidden layer node 9 performed best of the best regression coefficient (R2= 99.4%) with minimum error (MSE = 0.04). The comple investigation of the outcomes indicating towards the suitability of the existing model as an important one for accurately predicting the UCS. A thorough framework for improving quality management in Indian civil engineering projects is the research’s final product, and it offers insightful information to industry stakeholders.

In this research, a new idea was implemented to combine different models of artificial intelligence (AI) for evaluating the strength parameters of concrete samples in laboratory. To do this, a series of laboratory data related to concrete samples containing eight different parameters were collected. The system was developed based on various AI models including multi-layer perceptron (MLP), random forest (RF), the k-nearest neighbors (KNN), and tree. The final model developed in this research was designed as a stacking-tree-RF-KNN-MLP structure. This new structure includes various characteristics of four different models that were optimized to achieve a stable structure to evaluate the compressive strength of concrete samples. Each of the basic models involves different parameters that affect the final system performance. By investigating and optimizing each of them, the stacking-tree-RF-KNN-MLP system was updated and finally the final model was obtained. This model covers the weaknesses of each of the basic AI models and uses their best performance in order to get higher prediction capacity. The results of coefficient of determination (R2) showed that the developed model has an accuracy of 0.995 and 0.962 for training and testing data, respectively, which is able to create a suitable structure to predict the compressive strength of concrete samples. In addition, the stacking-tree-RF-KNN-MLP model developed in this research, compared to other models, receives a lower level of system error. The newly developed model can be used in other fields related to construction and material for solving relevant problems.

The widespread application of antibiotics, such as tetracycline (TC), has led to severe environmental problems. Herein, the rod-like Mn0.3Cd0.7S (MCS) coupled with flower-like FeNi8-LDH self-assembled from nanosheets S-scheme heterojunction is successfully constructed by a simple physical ultrasonic-assisted combined with a grinding method. The optimized MCS/30FeNi8-LDH heterojunction exhibits excellent photocatalytic degradation of TC under visible light with a removal rate of 72.5% within 30min along with excellent cycling stability, which enhanced 14.5 and 1.68 times compared to those of pristine FeNi8-LDH and MCS. The correlation between S-scheme heterojunction and photocatalysis performance clarify the rapidly transfer pathway of photogenerated carriers between MCS and FeNi8-LDH. The trapping experiment confirms •O2-and h+are the primary active species, with h+playing a dominant role in the degradation process. The enhanced photocatalytic degradation performance can be attributed to the formation of S-scheme heterojunction with well-matched band alignment, which remains the powerful reduction capability of generated electrons of FeNi8-LDH and more robust oxidation capability of photogenerated holes of MCS. This work not only provides a potential solution for photocatalysis degrading TC, but also expands the S-scheme heterojunction construced strategy to the realm of energy storage and conversion.

Alkali-activated binders based on technogenic fibrous waste (TFW) were developed. An increase in the specific surface area (Ssp) of TFW makes it possible to change the strength parameters. Thus, at Ssp= 160 m2/kg, the strength of the binder was 1 MPa, at Ssp= 220 m2/kg, an increase in activity by almost 3 times is noted (compressive strength 3.2 MPa). With an increase in the specific surface of the particles, the microstructure of the binder samples is characterized by a higher density, with a small number of cavities not filled with hydration products. Analysis of the microstructure revealed the presence of a denser matrix in all cases compared to the compositions obtained with a lower specific surface area of TFW. The pressed sample has a dense matrix with an increased number of contact zones between particles; TFW fibers are clearly visible over the entire surface under study. When the alkaline activator NaOH is introduced into the system, the solubility of the crystalline phases of pyroxenes (albite, anorthite) and quartz increases, which is noted by a decrease in the intensity of diffraction reflections. The main chemical composition in the binder is represented by oxides of SiO2, Na2O, CaO, MgO, Al2O3. The presence of sodium-calcium hydroaluminosilicate compounds in the synthesized system of compounds is confirmed by differential thermal analysis. The endothermic peak at 733 °C is associated with the decomposition of sodium-calcium hydroaluminosilicates. The exoeffect peak at 900 °C is associated with the crystallization of tobermorite-like compounds C–A–S–H and C–S–H into wollastonite. The presence of hydrosilicate tobermorite-like compounds is also confirmed by microstructural analysis, where almost the entire surface of waste particles is covered with fibrous new growths, which, most likely, belong to calcium silicate hydrates of tobermorite type C–A–S–H.

The development of promising concrete mixtures with improved performance is an important scientific problem of modern building materials science. This article presents the effect of mono and polydisperse reinforcement on the rheological properties of concrete mixtures and the physical and mechanical properties of self-compacting concrete (SCC). A central compositional plan determined the content of polydisperse reinforcement in the composition of the SCC: metal fiber of 0.56% (by volume), polypropylene fiber of 0.35% (by volume). It is shown that the installation of concreted structures with a slope of up to 4% is possible with the following rheological parameters of the concrete mixture: within the spreading grade SF1, the ultimate shear stress is 23–28 Pa, viscosity (spreading test t500according to EN 12350-8:2019) - 8 − 13 s. At the same time, the lower limit of the identified intervals of rheotechnological parameters is due to the content of metal fiber, with an increase in which from 0.5% to 0.8% (by volume) the workability decreases (from 59 to 60 cm to 54–55 cm) and the ultimate shear stress increases ( by 2.5–3 Pa). The upper limit of the studied parameters is due to the content of polypropylene fiber (0.3–0.4% by volume) and metakaolin (4–5%), with an increase in which the viscosity increases (by 30–35%). Self-compacting concrete has been developed with high values of frost resistance and water resistance, recommended for use in load-bearing building structures, industrial floors, and bending elements.

Demolition of existing deteriorated structures and construction of the new structures is a costly, time-consuming, and resource-intensive process. Repair of concrete beams and strengthening techniques for existing reinforced concrete elements is a resource-saving exercise that is time-saving also. In this work, a repair material using metakaolin-based alkali-activated concrete (AAC) is developed with high early compressive strength and split tensile strength designed with proper mix proportions. The flexural strength of reinforced concrete beams was determined without the new repair material. The specimens were loaded until failure and the deflected portion of the RC beam was then confiscated using breakers. The confiscated portion is subsequently replenished with metakaolin-based AAC and flexural strength and bond characteristics were determined. Shrinkage length changes were also measured. The metakaolin-based AAC with 15% metakaolin had a high stiffness and increased flexural strength up to 14.4% compared to the specimen before repair. It also exhibited a significant bonding with the concrete substrate with less shrinkage and improved strength.

This study performed a scientometric evaluation of the bibliometric data on self-healing concrete (SHC) in order to determine its major components. Manual review articles are inadequate in their capability to connect diverse areas of the literature in a systematic and ordered manner. Current research's most difficult parts include scientific mapping, co-occurrence, and co-citation. The Scopus search engine was utilized to locate and collect the necessary information for the investigation. During the data review, the important publishing sources, assessment of keywords, prolific authors based on citations and publications, most-cited articles, and areas actively engaged in SHC research are identified. VOSviewer was used to examine the literature records from 1294 relevant publications, which comprised abstract, citation, bibliographic, funding, keyword, and other data. In addition, the limitations associated with the use of SHC in the building industry were investigated, as well as potential solutions to these limitations. Due to the quantitative and graphical description of participating nations and researchers, this study can aid academics in developing joint projects and disseminating new ideas and approaches.

Achieving net-zero emissions requires rapid decarbonization and improved strategies implemented at the global level. In response to increasing demand for better structures and foundations, the concrete industry now relies on heating furnaces to over 1400 °C by burning fossil fuels and other cementitious materials, accounting for about 7–8% of carbon emissions. Even though the timeframe set by the Paris Agreement by United Nations (UN) to radically limit carbon emissions and improve carbon recovery is relatively short, i.e., countries reduce their Greenhouse Gas emissions to 'net zero' by around 2050, it still exceeds the time it has left to avoid the worst effects of global warming. Empirical evidence suggests that the management of carbon in the Earth’s ecosystems is still in the hands of humans and that effective strategies can be employed to restore carbon stocks and achieve net-zero emissions. This paper considers carbon emissions and recoverable carbon from a global perspective to identify the sources of CO2emissions, the status of CO2recovery strategies and implementation, and practical strategies to improve CO2recovery in Portland cement production. A literature review shows that several decarbonization pathways have been adopted to manage CO2recovery, namely alternative materials, fossil fuel substitution, and carbon capture and storage (CCS). However, no carbon recovery pathway sufficient to achieve net-zero emissions has been identified. Therefore, a comprehensive study of the Portland cement industry and CO2recoverability is needed to fully quantify carbon emissions and establish optimum strategies in terms of sustainability, cost-effectiveness, and business climate supported by strong political policies and associated regulations.

This experimental investigation reveals the projected benefits of concrete-filled double-skin tubular columns. These columns are made up of an outside steel tube, an interior UPVC pipe, and a sandwich of concrete among these tubes. The effect of the dimension ratio of the outer-to-inner tube, the thickness ratio of the outer tube, and the internal tube material (steel/UPVC) on the ultimate compressive strength of double-skin tubular columns samples filled with concrete are investigated. Finally, the experimental findings were compared to previously published design approaches in AISC (2010), GB50936 (2014), and EC4 (2004). The analysis revealed that GB50936 (2014) produces the best outcomes, followed by AISC (2010) and EC4 (2004). In addition, the samples were tested in elevated temperatures to study their post-fire axial capacity. It was discovered that the type of infilled concrete and interior tube material has no major impact on the performance of samples at elevated temperatures.

For decades, lightweight concrete has been used in various civil engineering applications. Cellular concrete is a type of lighweight concrete that is an emerging composite in materials engineering still. However, due to its low weight, it can be integrated with industrial by-products to develop more advanced composites such as ultra-lightweight cellular concrete (ULCC). ULCC is sustainable and regarded as a potential candidate due to its simplicity of use and other benefits. A systematic review of the potential applications of ULCC in geotechnical construction are presented in this review article. Due to technological breakthroughs and changes in environmental conditions, and their material property is one of the variables that influence the degradation of roadway. Several investigations have been conducted by incorporating different materials into pavement structures to achieve longer-lasting and better pavement infrastructures than those at present. Sustainability benefits, workability, low prices, time, and structural capacity are factors that have been widely focused. This study focuses on the raw materials, production techniques, types, and properties of the ULCCs. The boundary densities of the ULCCs were considered from 400 to 1600 kg/m3. Structures all across the globe have benefited from the usage of cellular concrete in some form or another. However, much work in this field should be focused on, particularly in geotechnical applications. Geotechnical applications need specific attention to develop this kind of concrete with enhanced qualities. In order to address this need, this review paper has extensively focused on raw materials, manufacturing procedures, cellular concrete characteristics, types and uses of ULCC, particularly in geotechnical applications. Furthermore, several limitations and gaps in ULCC application in highway construction are highlighted, and recommendations on further improving its use and performance are provided.