Infrastructure Applications Research Articles

Combined Loading Effects on the Buckling Strength of Q690 Steel Tubes: An Experimental and Numerical Study

Abstract: This study investigates the stability and buckling behavior of Q690 high-strength steel cylindrical tubes subjected to combined axial compression and bending loads. Experimental testing on 27 specimens, combined with finite element analysis using ABAQUS, revealed critical insights into load-bearing capacity, deformation patterns, and failure modes. The study found that geometric imperfections, such as initial out-of-roundness and local dents, and residual stresses significantly influenced the buckling strength of the tubes, particularly those with high diameter-to-thickness ratios. Finite Element Analysis (FEA) effectively modeled the complex behavior, with deviations from experimental results ranging from 5.6% to 7.9%. Based on these findings, design recommendations, including optimized D/t and slenderness ratios, are proposed to enhance structural safety and efficiency. These results contribute to a better understanding of Q690 steel behavior and can inform the development of improved design codes for critical infrastructure applications

Resilience Assessment in a Seawater Pumping Station Using Ordinal Patterns and Permutation Entropy Approach

The increasing demand for water in arid regions has driven the adoption of seawater desalination plants as critical infrastructure for industrial and domestic applications. However, these plants face unique challenges, including high operational costs, environmental vulnerabilities, and system reliability concerns. The critical nature of these infrastructures demands maintaining elevated levels of availability and demonstrating robust resilience. Resilience is framed as the system’s capacity to recover from disruptions and maintain operational efficiency under varying conditions. Quantitative assessment of resilience is essential to facilitate the development and implementation of optimal strategies that ensure operational continuity. This paper puts into practice a novel approach to evaluate the resilience of a seawater intake and pumping system using permutation entropy computed using time series availability data derived from different maintenance strategies. The methodology integrates reliability block diagrams (RBD) and symbolic time series analysis to identify critical components and evaluate maintenance strategies. A case study of a seawater pumping station demonstrates the application of the proposed resilience index. The analysis explored four scenarios to evaluate how these changes improved the system’s resilience: the first three hypothetical scenarios involved testing improvements in the maintainability and reliability indexes of the critical pump. These improvements matched the values of these parameters to the benchmark of the pump, historically showing the best indicators, first one by one, separately, and then both changes simultaneously. The initial resilience index was 0.652 in the baseline scenario. Scenario 1 (reduction in MTTR) showed a negligible impact, while scenario 2 (reduction in downtime) increased the resilience index to 0.682. The combination of both (scenario 3) maintained the index at 0.682, emphasizing the importance of reducing downtimes. Scenario 4, which consisted of reducing and standardizing the frequency of planned maintenance to 100 h, significantly raised the resilience index to 0.778. The results highlight how adjustments in maintenance strategies, including the reduction in preventive interventions, impact the system’s resilience and availability. The study also underscores the importance of aligning maintenance strategies with resilience goals to enhance the operational reliability of marine infrastructure. By providing a quantitative tool for resilience assessment, this work contributes to the sustainable management of desalination plants and offers practical insights for engineers and decision-makers in the marine engineering and water management sectors.

Piping Material Selection in Water Distribution Network Using an Improved Decision Support System

This study introduces an integrated Multi-Criteria Decision Making (MCDM) methodology combining the Analytic Hierarchy Process (AHP), Entropy Weight Method (EWM), and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) to optimize the selection of municipal water supply pipeline materials. A comprehensive evaluation system encompassing thirteen criteria across technical, economic, and safety dimensions was developed to ensure balanced decision-making. The method employs a weight determination model based on Jaynes’ maximum entropy theory to harmonize subjective AHP-derived weights with objective EWM-derived weights, addressing inconsistencies in traditional evaluation approaches. This framework was validated in a case study involving a DN400 pipeline project in Jiaxing, Zhejiang Province, China, where five materials—steel, ductile iron, reinforced concrete, High-Density Polyethylene (HDPE), and Unplasticized Polyvinyl Chloride (UPVC)—were assessed using quantitative and qualitative criteria. Results identified HDPE as the most suitable material, followed by UPVC and reinforced concrete, with steel ranking lowest. Comparative analysis with alternative MCDM techniques demonstrated the robustness of the proposed method in balancing diverse factors, dynamically adjusting to project-specific priorities. The study highlights the flexibility of this approach, which can extend to other infrastructure applications, such as drainage systems or the adoption of innovative materials like glass fiber-reinforced plastic (GFRP) mortar pipes. By integrating subjective and objective perspectives, the methodology offers a robust tool for designing sustainable, efficient, and cost-effective municipal water supply networks.

Cross-sectional optimisation of I-shape pultruded FRP beams using search-adaptive micro-population genetic algorithm

Despite the growing utilisation of pultruded fibre-reinforced polymers (PFRP) profiles in infrastructure applications, there is still a scarcity of design tools with a feasible computational cost. Such shortage deprives these profiles of competing with economic cost and optimised performance against other construction materials. This research investigated the numerical optimisation of cross-sectional geometry and anisotropy ratio of I-shape PFRP beams for the design against local buckling of flange under bending and web under transverse compression. A new search-adaptive micro-population genetic algorithm (SA-µP GA) tool was proposed to achieve accurate results with low computational cost. This tool was verified and compared with other GA codes from the literature. The artificial neural networks (ANNs) machine learning tool was used to maximise the use of data and generate practical and economic design charts considering the varying interactions between the design parameters. This optimisation approach represents an efficient design tool to achieve the design requirements of stability, strength, and serviceability (stiffness) limits with minimum cost and optimal structural performance. The optimisation approach was addressed using four case studies from the literature.

The Implementation Strategy of Cost Control and the Construction of a Guarantee Model of Financial BPO in the Cloud Computing Environment

Cloud computing platform is a main direction of computer information technology development at present. In this paper, financial SMOTE algorithm, business process outsourcing, hardware, software, data and other resources such as integrated network storage infrastructure, data resources, management platform, servers and various financial service applications are adopted. According to the service functions and service modes provided by commercial cloud computing, a financial information system architecture based on cloud computing is constructed. The proposed method can control the cost by 60%,Improve the financial management level and efficiency of enterprises in an all-round way, provide important decisions for the development of enterprises' market operation, avoid market operation risks in time, and provide more opportunities for enterprises' development.

A THEORETICAL REVIEW ON THE ROLE OF NATURAL FIBRES IN SUSTAINABLE PAVEMENT SUBGRADE STABILIZATION

The rapid deterioration of pavements built over soft soils is a persistent challenge in road construction, often resulting in high maintenance costs and reduced service life. Traditional methods of improving weak subgrade soils include chemical stabilization using lime, cement, or other additives. However, these methods raise environmental concerns due to their high carbon footprint. In recent years, the use of natural fibres as a sustainable solution for subgrade stabilization has gained attention. Natural fibres such as coir, jute, sisal, and bamboo offer numerous advantages, including biodegradability, low cost, and the ability to reduce shrinkage and desiccation cracks in soil. This paper presents a comprehensive theoretical review of natural fibre-based soil stabilization techniques, focusing on their role in enhancing soil strength and reducing pavement deterioration. The study explores the mechanical properties of various natural fibres and their interactions with different soil types. It also examines key factors affecting fibre performance, such as fibre length, dosage, orientation, and degradation over time. Additionally, this paper addresses the sustainability benefits and limitations of using natural fibres in pavement construction, with an emphasis on future research directions and practical applications in road infrastructure. The findings from this theoretical review suggest that natural fibre stabilization can be an effective, eco-friendly approach to improve pavement performance, especially in regions with abundant natural fibre resources. By promoting sustainable construction practices, the use of natural fibres can help reduce the environmental impact of road projects and contribute to achieving global sustainability goals in the construction sector.

Non-Linear Control Based Class-D Amplifier for Audio Intelligent Infrastructure Applications

Non-Linear Control Based Class-D Amplifier for Audio Intelligent Infrastructure Applications

Approach Towards the Development of Digital Twin for Structural Health Monitoring of Civil Infrastructure: A Comprehensive Review

Civil infrastructure assets’ contribution to countries’ economic growth is significantly increasing due to the rapid population growth and demands for public services. These civil infrastructures, including roads, bridges, railways, tunnels, dams, residential complexes, and commercial buildings, experience significant deterioration from the surrounding harsh environment. Traditional methods of visual inspection and non-destructive tests are generally undertaken to monitor and evaluate the structural health of the infrastructure. However, these methods lack reliability due to the need for instrumentation calibration and reliance on subjective visual judgments. Digital twin (DT) technology digitally replicates existing infrastructure, offering significant potential for real-time intelligent monitoring and assessment of structural health. This study reviews the existing applications of DTs across various sectors. It proposes an approach for developing DT applications in civil infrastructure, including using the Internet of Things, data acquisition, and modelling, together with the platform requirements and challenges that may be confronted during DT development. This comprehensive review is a state-of-the-art review of advancements and challenges in DT technology for intelligent monitoring and maintenance of civil infrastructure.

Navigating the Landscape of Kubernetes Security Threats and Challenges

The rise of containerization and the widespread adoption of Kubernetes have revolutionized the way applications are deployed and managed. This paradigm shift has introduced new security risks and challenges that must be addressed. This paper delves into the various security threats and vulnerabilities associated with Kubernetes, exploring mitigation strategies and best practices to enhance the overall security posture of containerized environments. Kubernetes, as a leading container orchestration platform, has become the de facto standard for managing and scaling containerized applications in modern IT infrastructure. While Kubernetes offers numerous benefits, such as improved scalability, portability, and resource optimization, it also introduces a unique set of security concerns that must be carefully navigated. This paper aims to provide a comprehensive overview of the security threats and challenges faced in Kubernetes environments, as well as the current approaches and tools used to address these critical issues.

Participation of Polymer Materials in the Structure of Piezoelectric Composites.

This review explores the integration of polymer materials into piezoelectric composite structures, focusing on their application in sensor technologies, and wearable electronics. Piezoelectric composites combining ceramic phases like BaTiO3, KNN, or PZT with polymers such as PVDF exhibit significant potential due to their enhanced flexibility, processability, and electrical performance. The synergy between the high piezoelectric sensitivity of ceramics and the mechanical flexibility of polymers enables the development of advanced materials for biomedical devices, energy conversion, and smart infrastructure applications. This review discusses the evolution of lead-free ceramics, the challenges in improving polymer-ceramic interfaces, and innovations like 3D printing and surface functionalization, which enhance charge transfer and material durability. It also covers the effects of radiation on these materials, particularly in nuclear applications, and strategies to enhance radiation resistance. The review concludes that polymer materials play a critical role in advancing piezoelectric composite technologies by addressing environmental and functional challenges, paving the way for future innovations.

Prioritizing Pathways Based on Satisfaction of Individuals Using Mobility Aids with Urban Road Infrastructure—Application of FSE and PROMETHEE II in Saudi Arabia

The convenience of commuting for individuals using mobility aids (IMAs) depends on various features of urban road infrastructure. The present research selected different pathways based on the relevance and convenience of IMAs in three regions of Saudi Arabia, including Riyadh, Qassim, and Hail. A survey questionnaire was developed to evaluate the satisfaction of IMAs with four critical criteria of road infrastructure, including travel distance, slope, availability of footpaths, and number of junctions, using a 5-point Likert scale from very low to very high. A sufficient sample size of this exceptional proportion of the population from different genders, age groups, education levels, employment status, number of disability years, and types of mobility aid participated in the survey. The main reasons for dissatisfaction of more than 50% of the participants were inadequate infrastructure design of entrances to public facilities, pedestrian crossings, and junctions. Social stigma and inadequate assistive technology were also highlighted by around 20% of the participants. The fuzzy synthetic evaluation identified length, slope, and footpaths along the pathway as the most critical features based on the subjective opinion of the participants, of which around 65% have been using artificial limbs or manual wheelchairs. PROMETHEE II aggregated the importance of weights estimated by the participants’ opinion and performance scores of infrastructure features to effectively rank ten pathways in three major cities of the selected regions, using partial and complete outranking. The framework developed in the present study helps concerned organizations to comply with the Vision 2030 goal of a vibrant society in Saudi Arabia by identifying critical pathways and improving infrastructure design to ensure safety, convenience, and satisfaction for IMAs.

Pulse Electrodeposition for Carbonate-Rich Deposits from Seawater

Seawater electrodeposition is gaining renewed interest in the context of sustainable development, both to build climate-resilient coastal infrastructure and for ocean-based decarbonization applications. Most of the applications benefit from CaCO3-rich deposits, but constant-voltage electrodeposition results in a mixture of CaCO3 and Mg(OH)2, especially at higher voltages where precipitation rates are more desirable. The use of pulse voltages can help control interfacial pH that dictates the precipitation reactions. Here, we explore the use of pulse electrodeposition as a function of pulse frequency and duty cycle to control deposit composition. The most CaCO3-rich deposits were obtained under 10 Hz frequency and 10% duty cycle conditions for the voltage window investigated (−0.8 V to −1.2 V vs. SCE). While pulsing the voltage increases the amount of CaCO3 deposited, the energy required per gram of CaCO3 is significantly higher (14.5×) when compared to the base case of applying a constant voltage of −0.8 V vs. SCE. Further optimization of pulse conditions, electrode materials, and system configuration could lead to finding parameters that result in exclusively carbonate deposits without compromising precipitation rates, which may prove to be more useful for corrosion protection, coastal infrastructure, and other applications in sustainable development.

Impact Analysis of the Digital Entrepreneurial Ecosystem to Improve the Tourism Industry and Social Sustainability

Digitalisation is a key enabler of sustainable tourism in an industry that has recently been transformed by new sustainable innovations and digital solutions. In this study, we analysed the effects of the digital entrepreneurial ecosystem (DEE) on the tourism industry and social sustainability of 27 EU countries. The study underlines the key independent indicators representing the impact of the DEE’s elements. Also, a quantitative and comparative approach was considered using the panel data method and clustering analysis for data from 2014 to 2021. Our findings show significant positive impacts of DEE elements that have significantly contributed to tourism and social sustainability growth. Furthermore, hierarchical clustering analysis (HCA) revealed that eight countries (cluster A), including Germany, the UK, France, Spain, and Italy, had the highest average digitalisation levels, affecting their tourism growth and social sustainability. Ultimately, we indicate different digital user levels and marketplace, such as networks designed to produce cloud infrastructure, digital platforms, and digital tourist-based devices and applications, as having the capability to enhance tourism and social sustainability.

A review paper on performance evaluation of bacteria induced concrete for rigid pavements

Concrete is a foundational material renowned for its performance across a spectrum of applications in construction and infrastructure. it is indispensable in meeting the diverse demands of modern engineering and architecture, from towering skyscrapers to intricate bridges, from residential homes to transportation networks, concrete's performance capabilities have shaped the built environment in profound ways. But conventional concrete is susceptibility to cracking, especially under tensile stresses. This can compromise the structural integrity of concrete elements and lead to durability issues and reduced service life. Rigid pavements are vulnerable to cracking due to temperature changes, shrinkage, and severe loads. Cracks have the potential to undermine the pavement's structural integrity, hastening deterioration and raising maintenance requirements. Review paper describes the method that is used in showing the performance Evaluation of concrete Through the process of carbonate ion formation, a microorganism secretes calcium precipitate externally, forming CaCo3. This fills in the holes in the concrete texture, increasing its compactness. Conversely because of the expansion of the filler fabric inside the concrete mixer's pores, this improves the strength of the concrete. In the laboratory tests has been carried out to study the impact of introducing bacteria on concrete. here compressive strength, flexure strength, split tensile strength and durability test on Bacteria induced Concrete is studied and SEM and XRD analysis is also carried about to the study the microstructure of Bacteria induced concrete.

Bio-colonisation, durability, and microstructural analysis of concrete incorporating magnetite and oyster shell waste aggregates in marine environment

This study evaluates the impact of bio-colonisation and seawater attack on the durability, microstructure and mineralogy of two distinct concrete formulations. These formulations are designed to meet the specifications of marine infrastructure applications, particularly those intended as biomimetic solutions for infrastructures typically used for boat anchoring, which are commonly responsible for the displacement and destruction of marine habitats. The first formulation incorporates magnetite aggregates, resulting in a heavy concrete capable of stabilising the base structure of the biomimetic concrete mooring. In the second formulation, natural gravel is partially substituted by oyster shell waste, to reduce the carbon footprint of these marine infrastructures. Experimental tests were conducted to evaluate the bio-colonisation and durability of the two concrete formulations under marine exposure. After 24 months of immersion, the surface biomass on both formulations exhibited similar kinetic bio-receptivity, primarily attributed to the binder and surface roughness rather than the type of aggregates used. The porosity accessible to water decreases in marine conditions, suggesting that the biofilm contributes to this decrease. Durability results indicate that while both concrete types deteriorate under seawater exposure, the oyster shell aggregates demonstrated better resilience to natural seawater aggressiveness compared to magnetite aggregates over long-term exposure. Elemental mapping showed no obvious zonation of elements. However, a slight increase in surface roughness was observed, with no macroscopic damage detected. This research enhances our understanding of how magnetite and oyster shell waste aggregates respond to bio-colonisation and seawater attack, which are critical factors in the development of biomimetic marine infrastructure.

Genetic Neuro-Fuzzy Approach towards Routing in Industrial IoT

The Internet of Things has rapidly grown in the past years as emerging technology. Moreover, 5G networks start to offer communication infrastructure for applications of the Industrial Internet of Things (IIoT). However, due to energy limitations of IIoT devices and heterogeneity of 5G networks, managing IIoT networks is a challenging task. One of the most critical issues in IIoT that requires consideration is traffic routing that has a significant impact on energy consumption, and thus, lifetime of the network. Artificial Intelligence (AI) has been widely employed to solve complex scientific and practical problems. Such AI techniques as neural networks, fuzzy systems, genetic algorithms are commonly employed in wireless networks to promote their optimization, prediction, and management. This study suggests using an Adaptive Neuro-fuzzy Inference System (ANFIS) in 5G networks of IIoT for improving the routing process. A flow-chat of routing protocol was suggested. For input and output values of the ANFIS linguistic variables, terms and membership functions were defined. A rules base was developed. To improve the rule base of the ANFIS, a genetic algorithm was proposed. The operation of ANFIS was simulated in Matlab software.

Humidity and immersion based hygrothermal aging of pultruded GFRP composites: Moisture uptake and diffusion

Pultruded glass fiber reinforced polymer (GFRP) composites are used extensively in civil, marine, and offshore infrastructure applications. These components can be exposed to long periods of humidity or immersion with long-term performance characteristics being influenced by the rate and level of moisture uptake and its consequent effects. This paper reports on the moisture uptake response and kinetics of a pultruded GFRP composite exposed to a range of relative humidity levels and immersion over a range of temperatures below the glass transition. Four models for diffusion are used to assess the range of uptake responses. It is seen that humidity and temperatures have a significant effect on both rate of uptake and maximum apparent uptake level with there being a significant difference between effects of 99% RH and immersion emphasizing that immersion, as is often used in durability testing, cannot be directly used as a substitute for accelerating effects of humidity even at high levels. The two-stage structural modification model which considers both an initial diffusion dominated regime and a second relaxation/deterioration dominated regime is seen to best model the range of uptake regimes and characteristics while the simple Fickian model is shown to be deficient in modeling most of the regimes accurately.

Development of Sustainable Cement Asphalt Mortar Using Agricultural Waste-Derived Bio-Oil and Latex-Acrylic Polymers for Enhanced Durability.

Cement Asphalt Mortar (CAM) is widely applied in infrastructure, particularly in railways, bridge expansion joints, and pavements, due to its combination of cement's load-bearing capacity and asphalt's flexibility. Conventional CAM formulations, however, often encounter challenges such as extended setting times, high shrinkage, and limited durability under extreme environmental conditions. This study addresses these limitations by integrating bio-oil and polymer additives to enhance both the sustainability and performance of CAM mixtures. CAM mixtures were evaluated with cement-to-asphalt emulsion (C/AE) mass ratios of 75:25 and 50:50, incorporating bio-oil contents of 2% and 4% by mass and latex-acrylic polymer proportions ranging from 1% to 2% by mass. The optimized mix design, with a 75:25 cement-to-asphalt emulsion (C/AE) mass ratio, 2% bio-oil, and 1.5% polymer, improved flowability by 25%. This formulation achieved a flow diameter of approximately 205 mm and reduced the flow time to 72 s. Compressive strength tests indicated that this formulation reached an early-stage strength of 10.45 MPa (a 20.8% improvement over the control) and a 28-day strength of 24.18 MPa. Thermal stability tests at 45 °C demonstrated that the optimized CAM retained 86.6% of its compressive strength, compared to a 25% reduction in unmodified mixtures. Chemical resistance assessments in 5% sulfuric acid and 5% sodium hydroxide solutions showed strength retention of 95.03% and 91.98%, respectively, outperforming control mixtures by 17% and 13%. SEM examination revealed a dense, cohesive microstructure, reducing shrinkage to 0.01% from 0.15% in the control. These findings underscore the potential of bio-oil and latex-acrylic polymers to improve the performance and sustainability of CAM mixtures, making them well suited for resilient, rapid-setting infrastructure applications.

Hybrid RBFN-GWO Approach for Energy-Efficient and Secure Routing in Intelligent IoT Networks for Precision Farming

This paper introduces a hybrid approach combining Radial Basis Function Networks (RBFN) and Grey Wolf Optimization (GWO) to address the challenges of energy efficiency and security in Intelligent IoT networks for precision farming. Our proposed method utilizes RBFN for feature extraction and classification of network states, while GWO optimizes the routing parameters to achieve an optimal balance between energy conservation and security. The hybrid RBFN-GWO algorithm adapts to dynamic network conditions and evolving security threats in real-time. Extensive simulations using real-world precision farming data demonstrate that our approach outperforms existing protocols, achieving a 20% increase in network lifetime and a 15% improvement in intrusion detection accuracy. This research contributes to the development of more efficient and secure IoT infrastructures for precision agriculture applications.

Optimal design of electrical conductivity of hybrid multi-dimensional carbon fillers reinforced porous cement-based Composites: Experiment and modelling

Cement-based composites with tailored electrical conductivity have promising applications in various intelligent and multifunctional infrastructures. Hybrid reinforcement using multi-dimensional carbon nanofillers is an effective approach for tailoring. However, determining the optimal recipe while balancing electrical properties and cost is challenging, which has not been carried out previously. This study develops a comprehensive micromechanical model with imperfect micromorphology, interface effect and electron tunneling to predict the electrical conductivity of cement-based composites reinforced with different combinations of 0D (zero-dimensional)-carbon black (CB), 1D-carbon nanotube (CNT) and 2D-graphene nanoplatelet (GNP). The influence of pore orientation on the electrical conductivity of the carbon nanofiller reinforced cement-based composites (CNRCCs) is studied for the first time and an effective conductive cross-sectional area method is proposed to investigate the anisotropy of the electrical conductivity in the CNRCCs. Furthermore, this model captures the synergistic effects of the hybrid carbon nanofillers, which has not been addressed in existing theoretical work on conductive composites. The developed model exhibits outstanding agreement with the experimental data of various samples. The optimal proportions for maximum electrical conductivity and performance-to-cost ratio are identified, such as mixing ratios of 80:20 for 0D-CB + 1D-CNT, 50:50 to 70:30 for 0D-CB + 2D-GNP, and 90:10 for 1D-CNT + 2D-GNP. The work is envisaged to provide guidelines for optimizing the performances of CNRCCs with tailored electrical properties and moderate cost.