CivilEng

The analysis of the impact of the construction of the subway protection zone on the adjacent subway tunnel has become the premise on which to ensure the safe operation of the tunnel. The need for expert members to carry out safety assessments based on specific calculations to determine the impact of construction on the safety of protected tunnels is extremely inconvenient for safety management and significantly reduces management efficiency. This paper analyzes and qualitatively judges the influence range and disturbance size of pile foundation construction, shallow foundation engineering, and foundation pit excavation. Based on relevant research results from scholars and numerical simulation methods, quantitative analysis and comparison are performed on the parameter sensitivity of pile foundation engineering, shallow foundation engineering, and foundation pit engineering along the subway line, and the influence of multi-factor combination is studied and discussed to obtain the influence sensitivity of each factor. The results show that the increase in pile spacing can effectively reduce the pile group effect. The sensitivity of subway tunnel settlement displacement is mainly controlled by the settlement displacement value. The larger the settlement displacement is, the stronger the sensitivity is. The loaded pile foundation arranged along the direction of the subway tunnel has more obvious disturbance to the subway tunnel than that arranged perpendicular to the direction of the subway tunnel. Full article

Automation is revolutionizing a number of sectors, including construction, by bringing about important technological breakthroughs that increase productivity and efficiency. Automation in safety procedures is still scarce though. In India, the majority of safety procedures are still reactive, manual, and paper-based. This study is a component of a broader research project on automated safety screening for fall risks enabled by BIM. It entails codification of OSHA rules to perform safety checks, placing corrective actions into location, and generating reports in a virtual environment. As part of the broader risk lifecycle, these tasks are typically completed on-site during the various stages of construction. This study, on the other hand, executes these steps in a virtual environment in the preconstruction phase. The model has been assessed in a pilot study in India and was developed especially to address fall hazards from staircases. Through early hazard identification and mitigation, the system assists professionals in enhancing overall safety performance. Full article

Various stabilizers, such as jute, gypsum, rice-husk ash, fly ash, cement, lime, and discarded rubber tires, are commonly used to improve the shear strength and overall characteristics of clay subgrade soil. In this study, waste foundry sand (WFS) is utilized as a stabilizing material to enhance the properties of clay subgrade soil and strengthen the bond between clay subgrade soil and subbase material. The materials employed in this study include Type B subbase granular materials, clay subgrade soil, and 1100 Biaxial Geogrid for reinforcement. The clay subgrade soil was collected from the airport area in the Al-Muthanna region of Baghdad. To evaluate the effectiveness of WFS as a stabilizer, soil specimens were prepared with varying replacement levels of 0%, 5%, 10%, and 15%. This study conducted a Modified Proctor Test, a California Bearing Ratio test, and a large-scale direct shear test to determine key parameters, including the CBR value, maximum dry density, optimum moisture content, and the compressive strength of the soil mixture. A specially designed large-scale direct shear apparatus was manufactured and utilized for testing, which comprised an upper square box measuring 20 cm × 20 cm × 10 cm and a lower rectangular box with dimensions of 200 mm × 250 mm × 100 mm. The findings indicate that the interface shear strength and overall properties of the clay subgrade soil improve as the proportion of WFS increases. Full article

Assessing risk in life-cycle cost and benefit estimates of highway investments is recommended by major organizations such as the World Bank and the U.S. Federal Highway Administration. This challenging task needs methodological support. Mutually exclusive investment alternatives can differ in terms of the costs of construction, maintenance, rehabilitation, and end-of-life value. Due to many causal factors and the long life of highway infrastructure, these items cannot be estimated with certainty. To go beyond the study of the sources of uncertainty, a method is needed to check the economic feasibility of acquiring additional information for deeper insight. This paper reports on research on the value of Bayesian pre-posterior information for refining the life-cycle cost analysis of uncertain costs and benefits for evaluating highway investment alternatives. Example applications demonstrate how the Bayesian pre-posterior analysis can be applied to check the feasibility of obtaining new information for enhancing the life-cycle cost analysis of highway investments. The value of Bayesian pre-posterior information is illustrated for reducing risk. Also, depending upon the specifics of uncertain states, a change in the choice of the investment alternative for implementation can be investigated. The product of this research can potentially upgrade highway infrastructure planning and management practices. Full article

Pavement deterioration is often the result of intense traffic and increased runoff from storms, floods, or other environmental factors. A practical solution to this challenge involves the use of permeable pavements, such as permeable interlocking concrete pavement (PICP), which are designed to effectively manage water runoff while supporting heavy traffic. This research investigates the effectiveness of PICP in two distinct surface patterns: stretcher bond and 45° herringbone, by assessing their performance in terms of water infiltration and runoff using two different methods. The first approach has been conducted experimentally using a laboratory apparatus designed to simulate rainfall. Various conditions were applied during the performance tests, including longitudinal (L-_Slope) and transverse (T-_Slope) slopes of (0, 2, and 4%) and rainfall intensities of (40 and 80 L/min). The second approach has been implemented theoretically using Surfer 2.0 software to simulate the distribution of infiltrated water underneath the layers of PICP. Moreover, the behavior of PICP has been analyzed statistically using artificial neural networks (ANNs). The results indicated that at a rainfall intensity of 40 L/min, equal infiltration was observed in both patterns on 0% and 4% T-_Slope. However, the 45° herringbone PICP showed better infiltration on the 8% T-_Slope. Additionally, at 80 L/min rainfall, equal infiltration was observed in both patterns on 0% L-_Slope for 0% and 4% T-_Slope. The 45° herringbone PICP also demonstrated higher water infiltration on the 8% T-_Slope, and this trend continued as the L-_Slope increased. PICP with a 45° herringbone surface pattern exhibited superiority in reducing runoff compared to the stretcher bond pattern. The statistical models for the stretcher bond and 45° herringbone patterns demonstrate high accuracy, as evidenced by their correlation coefficient (R²) values of 99.97% and 97.32%, respectively, which confirms their validity. Despite the variations between the two forms of PICP, both are strongly endorsed as excellent alternatives to conventional pavement. Full article

In order to ensure the safety of existing buildings constructed many years ago in zones with high seismicity, it is very important to consider and apply retrofitting measures. The seismic retrofitting of buildings can be achieved by techniques such as increasing the stiffness and ductility of the building and reducing the seismic demand. Energy dissipative devices such as various types of dampers are among the most popular and widely studied devices for improving the performance of buildings exposed to earthquakes. This paper presents a systematic literature review of the seismic retrofitting of existing buildings using energy dissipating devices. More than 230 journal and conference articles were collected from three well-known scientific resources published from 2010 to 2024. The main classification of papers considered was based on energy-dissipating devices employed for retrofitting goals. According to this analysis, there is a vast number of energy dissipative devices and design methods studied by scholars, and energy dissipation based on friction, viscous, and hysteretic mechanisms are the most useful for dampers. On the other hand, only relatively few articles were found about seismic loss assessment and the economic aspects of buildings retrofitted with the proposed damping tools. Full article

Temperature variations have a significant impact on the performance and durability of rigid (concrete) pavement. As concrete is subjected to daily and seasonal temperature changes, it experiences thermal expansion and contraction. These movements, if not properly managed, can lead to cracking, joint deterioration, and loss of structural integrity. The pavement system is adversely affected by intense heat and significant flooding. This study aims to analyze the impact of several parameters on the performance of rigid pavement under typical, thermal, and flooding situations. This study investigates the properties of concrete and the dimensional design of rigid pavement with FEACONS IV software to assess their impact on the performance of concrete pavement during thermal and flooding conditions. The main conclusions of this study derived from the FEACONS IV analysis are as follows. Rigid pavement can enhance load-carrying capacity due to a lower elastic modulus, adequate flexural strength, and aggregates with a lower coefficient of thermal expansion. Increased thickness of concrete slabs and shorter slab lengths assist in minimizing load- and temperature-induced stresses. The increase in the subgrade modulus reaction value during flooding conditions improves pavement strength. However, in higher thermal conditions, a higher subgrade reaction modulus can increase the stress induced by temperature and load. Rigid pavement using porous limestone aggregate exhibits a reduced elastic modulus and coefficient of thermal expansion, suggesting higher resilience compared to rigid pavement composed of river gravel or granite. The findings suggest that higher thermal conditions will cause pavement damage. Agencies need to account for higher temperatures while designing and maintaining pavement. Flooding saturates the concrete pavement and subgrade layer, adversely affecting its performance over time. Full article

This study aims to develop a reliable method for predicting power plant construction costs during the early planning stages using ensemble machine learning techniques. Accurate cost predictions are essential for project feasibility, and this research highlights the strength of ensemble methods in improving prediction accuracy by combining the advantages of multiple models, offering a significant improvement over traditional approaches. This investigation employed the Random Forest (RF) algorithm to estimate the overall construction cost of a power plant. The RF algorithm was contrasted with single-learner machine learning models: Support Vector Regression (SVR) and k-Nearest Neighbors (KNN). Performance measures, comprising the coefficient of determination ($R^2$), Mean Absolute Error (MAE), and Root Mean Squared Error (RMSE), were used to evaluate and contrast the performance of the implemented models. Statistical measures demonstrated that the RF approach surpassed alternative models, demonstrating the highest coefficient of determination for testing ($R^2=0.956$) and the lowest Root Mean Square Error (RMSE = 29.27) for the testing dataset. The Shapley Additive Explanation (SHAP) technique was implemented to explain the significance and impact of predictor factors affecting power plant construction costs. The outcomes of this investigation provide crucial information for project decision-makers, allowing them to reduce discrepancies in projected costs and make informed decisions at the beginning of the construction phase. Full article

Structural research teams face significant challenges when conducting studies with explosives, including the costs and inherent risks associated with field detonation tests. This study presents a replicable method for loading spherical and bare TNT-based cast explosive charges, offering reduced costs and minimal risks. Over eighty TNT and Composition B charges (comprising 60% RDX, 39% TNT, and 1% wax) were prepared using spherical molds made of thin aluminum, which are low-cost, off-the-shelf solutions. The charges were bare, meaning they lacked any casing, as the molds were designed to be easily removed after casting. The resulting charges were safer due to their smaller dimensions and the absence of hazardous metallic debris. Composition B charges demonstrated promising results, with their performance characterized through blast and thermochemical experiments. Comprehensive data are provided for Composition B charges, including TNT equivalence, pressures, velocity of detonation, DSC/TGA curves at four different heating rates, activation energy, peak decomposition temperatures, X-ray analysis, and statistics on masses and densities. A comparison between detonation and deflagration processes, captured in high-speed footage, is also presented. This explosive characterization is crucial for structural teams to precisely understand the blast loads produced, ensuring a clear and accurate knowledge of the forces acting on structures. Full article

The surface settlement of railroad tunnels is dynamically updated as the construction progresses, exhibiting complex nonlinear characteristics. The accuracy of the on-site nonlinear regression fitting prediction method needs to be improved. To prevent surface settlement and surrounding rock collapse during railroad tunnel construction, while also ensuring the safety of the tunnel and existing structures, we propose a recursive prediction model for the long-term trend of surface settlement utilizing a singular spectrum analysis (SSA), improved sand cat swarm optimization (ISCSO), and a kernel extreme learning machine (KELM). First, SSA decomposition, known for its adaptive decomposition of one-dimensional nonlinear time series, reorganizes the early surface settlement data. The dynamic sliding window method is introduced to construct the prediction dataset, which is then trained using the KELM. ISCSO is used to optimize the key parameters of the KELM to obtain the long-term trend curves of surface settlement through recursive time series prediction. The superiority and effectiveness of ISCSO and the model are verified through numerical experiments and simulation experiments based on engineering cases, providing a reference for the early warning and control of surface settlement during the construction of similar tunnels. Full article

PC steel material inside pre-stressed concrete bridges is prone to corrosion due to the effect of salt, which leads to cross-sectional losses and fractures if proper maintenance is not carried out, affecting the girders’ structural performance. In Japan, pre-tensioned girders incorporating small-diameter PC steel material with a span length of 13 m or less were used until the early 1980s. Thus, it is essential to understand the fracture conditions of PC steel material and the factors affecting section loss due to corrosion, in order to properly assess the residual strength of salt-affected pre-tensioned girders. Hence, the current research clarifies the accuracy of techniques used for detecting deterioration in a pre-tensioned PC girder that had been out of service for about 40 years, caused by exposure to the severely saline environment of the Okinawa coast. Visual and hammer-tapping investigation of the actual bridge in addition to fracture investigation of the PC steel material using the triaxial magnetic method and destructive investigation of the concrete cover on the bottom of the girder were carried out and correlated. The final results confirmed that the triaxial magnetic method could detect PC steel material fractures accurately, and valuable information was obtained regarding fracture-detection technology for application in PC girders via non-destructive testing. Full article

Rising industrialization and population growth contribute to the increasing generation of plastic waste, which poses significant environmental and health challenges. Despite its potential as a resource, plastic waste is often discarded without proper treatment. Repurposing it in road construction offers both economic and environmental benefits, providing a sustainable waste management solution. This paper thoroughly examines various types of plastic waste used in asphalt mixtures, considering both wet and dry processing methods and their impact on bituminous binders and asphalt performance. Overall, incorporating waste plastics into asphalt mixtures has been shown to improve fatigue resistance, rutting resistance, moisture resistance, and high-temperature performance. However, challenges related to compatibility and low-temperature performance persist in plastic-modified asphalt applications. To address these issues, modified approaches, such as the use of chemical additives, have been identified as effective in enhancing the bonding between waste plastics and bituminous binders while also increasing the amount of plastic that can be incorporated. While plastic-modified asphalt shows significant promise, overcoming these challenges through targeted research and careful implementation is essential for its sustainable and effective use in asphalt mixtures, ensuring long-term performance. Full article

The construction of highway bridges using continuous precast prestressed concrete girders provides an economical solution by minimizing formwork requirements and accelerating construction. Different ways can be used to integrate bridge continuity and enable the development of negative bending moments at piers. Continuous bridge connections enhance structural integrity by reducing deflections and distributing loads more efficiently. Research has led to the development of various continuity details, categorized into partial and full integration, to improve performance under diverse loading conditions. This review summarizes studies on both partial and fully integrated continuous bridges, highlighting improvements in connection resilience and the incorporation of advanced construction technologies. While extended deck reinforcement presents an economical solution for partial continuity, it has limitations, especially in longer spans. However, full integration provides additional benefits, such as further reduced deflections and bending moments, contributing to improved overall structural performance. Positive-moment connections using bent bars have shown enhanced performance in achieving continuity, though skewed bridge configurations may reduce the effectiveness of continuity. Ultra-High-Performance Concrete (UHPC) has been identified as a superior material for joint connections, providing greater load capacity, durability, and seismic resistance. Additionally, mechanical splices, such as threaded rod systems, have proven effective in achieving continuity across various load types. The seismic performance of precast prestressed concrete girders relies on robust joint connections, particularly at column–foundation and column–cap points, where reinforcements such as steel plates, fiber-reinforced shells, and unbonded post-tensioning are important for shear and compression transfer. Full article

Airport facility management requires innovative and coordinated techniques due to the infrastructure’s complexity, stakeholders’ diversity, and the necessity of safety. Adopting building information management (BIM) as an advanced technology has several benefits, including increased productivity, lower cost, and higher quality of service. This study seeks to determine the strategies for using BIM in airport facility management. In this vein, two questionnaires were developed to collect data based on a literature review. The first questionnaire was used to collect data for identifying and ranking the main criteria, and the second questionnaire was used to identify the practical strategies. The experts of this study answered five strengths, four weaknesses, five opportunities, and five threats using a standardized questionnaire. An integrated AHP-SWOT approach was used to identify and examine the practical strategies. Furthermore, a sensitivity analysis was used to ensure the results were correct. The findings showed that smart maintenance management, with a weight of 0.363, was the most important strength in the SWOT analysis. Resistance to change was the most important weakness, with a weight of 0.455. The increasing need for smart airports with a weight of 0.358 was the most important opportunity, while cybersecurity issues with a weight of 0.385 were the most important threat. Integrating BIM into the aviation sector can enhance efficiency and sustainability in airport facility management while addressing potential opportunities and shared hazards that extend beyond airport operations. Full article

Corrosion in steel girder ends, progressing from localized thinning of the web and the lower flange to severe perforation in severe cases, can significantly affect structural integrity. This study evaluates the effects of severe corrosion, including web–lower flange disconnection and transverse flange perforation combined with web damage, on the residual shear strength of steel girder end web panels through experimental and numerical methods. Results indicate that when only the web is affected, post-buckling strength starts to decline by corrosion damaging the plastic hinge on the tension flange, disrupting the tension field action. Conversely, in cases involving simultaneous web and lower flange damage, localized yielding at fracture points near the flange damage leads to the abrupt rotation of the tension field inclination angle, causing an earlier and more pronounced decline in post-buckling strength compared to web-only damage scenarios. Full article

Shells are significant structural components that are extensively utilized in numerous engineering fields, including architectural and infrastructural projects. These components are employed in the construction of domes, water tanks, stadiums and auditoriums, hangars, and cooling towers. Significant research efforts have been dedicated to the analysis of vibrations and dynamic behaviors of shells, due to their distinctive capacity to efficiently bear loads through their geometry rather than mass. Additionally, a vast array of shell theories and computational methods have been proposed and developed by researchers. This paper represents a continuation of research initiated begun in a 2009 paper by Elishakoff, wherein the suggestion was made to disregard an energetic term in the dynamic analysis of Timoshenko–Ehrenfest beams, wherein the suggestion was made to disregard an energetic term in the dynamic analysis of Timoshenko–Ehrenfest beams. The resulting reduced theory was found to be both more straightforward and more reliable than the complete, classical approach. While the original idea was heuristically justified, a more sound variationally consistent theory was proposed in the papers of De Rosa et al. concerning the dynamic analysis of the Timoshenko-Ehrenfest beams and later extended to the case of the Uflyand-Mindlin plates. In accordance with the proposal put forth in those works, we initially delineate the classical shell theory and subsequently propose two alternative hypotheses that give rise to two distinct aspects of the energy terms. By employing the variational approach, we derive two novel boundary problems, which are direct generalizations of those previously considered. Both theories can be readily specialized for beams and plates, and the theory can also be specialized for the case of cylindrical shells. Full article

The rapid progression in concrete technology and the emphasis on improving the mechanical characteristics and durability of concrete, as well as the need for skilled workers, were key factors that led to the fabrication of self-consolidating concrete (SCC). The primary advantage of SCC is the elimination of vibrations during construction. This experimental study investigates the effect of nano-silica, nano-clay, and micro-silica with ratios of 2% and 4% on the properties of SCC. To reach this aim, rheological tests (flow slump, V-shape funnel, U-shaped box, and L-shaped box tests), mechanical tests (compressive strength, tensile strength, and flexural strength test), and durability tests (freezing, abrasion, and permeability tests) were carried out. The results demonstrated that the mechanical characteristics and durability of the concrete were enhanced by increasing the nano-silica content up to 4% of the cement weight. Also, the increase in the nano-clay content produced suitable results for SCC in terms of mechanical and durability aspects. However, as the nano-material ratio increases, the amount of superplasticizer also increased to ensure the proper workability of the SCC. Full article

The productivity of the construction industry is about half that of the manufacturing industry, and the labor shortage in the construction industry is serious; therefore, improving productivity using information and communication technology (ICT) is an urgent issue. In addition, in civil engineering works, the number of projects that handle multiple types of soil and sand is increasing due to the recycling of construction waste soil; thus, traceability management is important to ensure quality. This paper presents a system that uses sensing on soil-transporting dump trucks and ICT to record which soil was piled up where with the aim of improving the efficiency of traceability management in earthwork construction. This system automatically creates traceability data by linking sensing data and data from the compaction management system via an application. This eliminates the need to record and manage the earthwork location, which was previously required manually to create traceability data, and reduces the labor and manpower required for traceability management. The created traceability data are automatically assigned attribute information such as the construction date and soil information; consequently, they can be used to check the construction history in the future. Full article

The employment of automated non-destructive testing (NDT) methods for crack characterization in concrete, needs calibration and benchmarking in a controlled environment. This requires test specimen with comparable and ideally reproducible cracks. To this end, in this paper a method is presented that aims to mimic cracked concrete specimens with a high degree of control over the resulting crack parameters width, depth and length for material testing and calibration of automated (NDT) methods. The method comprises 3D-printing of formwork with integrated crack patterns. The obtained crack width accuracy is tested by comparing printed cracks and resulting cracks in the concrete with the desired width from the print file. This procedure enables the realization of crack widths ≥ 0.2 mm with a deviation in the range of 25% between desired and resulting crack width. Further, the proposed methodology is independent of intrinsic material properties which enables this accuracy. Full article