Civil Engineering Journal
Not a member yet
2007 research outputs found
Sort by
Statistical Optimization of Blending Conditions and Performance Evaluation of Optimal Bio-Asphalt Content
No full textTo mitigate environmental impacts and promote sustainability in highway construction, this study investigates the optimization of blending conditions and the performance evaluation of bio-modified asphalt binder incorporating bio-asphalt derived from the pyrolysis of waste cooking oil (WCO) and low-density polyethylene (LDPE). A response surface approach was employed to optimize key blending parameters—temperature, speed, and time—based on critical physical properties of the binder. Furthermore, the optimized bio-asphalt binder was further evaluated through rheological performance tests (multiple stress creep recovery and linear amplitude sweep) and mechanical performance tests (Marshall stability, tensile strength ratio, resilient modulus, indirect tensile fatigue, and dynamic creep). The optimal conditions were identified as 130°C, 1000 rpm, and 42.37 min. Statistical validation using ANOVA, residual analysis, leverage, and Cook’s distance confirmed the model’s reliability, with prediction errors remaining below 5%. The bio-modified asphalt binder exhibited enhanced elastic recovery and reduced non-recoverable creep compliance (Jnr), indicating superior resistance to permanent deformation in comparison with the control asphalt binder. Additionally, the bio-modified asphalt mixture demonstrates superior Marshall stability, resilient modulus, tensile strength ratio, retained stability, and resistance to deformation in comparison with the control asphalt binder. These results demonstrate the potential of bio-asphalt as a viable, eco-friendly modifier for asphalt binders in tropical climates
Empirical Analysis of Risk Behavior in Truck Drivers Across Industrial Zones and Policy Recommendations
No full textTruck drivers play a crucial role in industrial development but face disproportionately high risks of traffic-related injuries and fatalities. These risks arise from complex traffic conditions, especially in truck-congested industrial zones, and economic pressures that encourage risky driving behaviors. This study investigates key factors influencing these behaviors among truck drivers in industrial zones using an integrated framework combining the Health Belief Model and Protection Motivation Theory, a novel approach in this context. A random parameter model was employed to account for unobserved heterogeneity in drivers’ responses. The results highlight several significant psychological factors: perceived susceptibility (when drivers perceive the risk of crashes while driving), perceived severity (when drivers feel that crashes will impact their work), perceived barriers (when truck drivers perceive that fastening seat belts causes discomfort and when they perceive safety equipment for vehicles as expensive and unaffordable), cues to action (when truck drivers encounter safe driving campaigns), and health motivation (when truck drivers prioritize adequate rest and relaxation). Additionally, the study identifies route familiarity as a random effect, revealing variations in how this factor influences behavior across individuals. The study provides practical, evidence-based policy recommendations aimed at reducing road injuries and fatalities among truck drivers, offering valuable insights for policymakers, transport authorities, and logistics stakeholders
Behavior of Full-Scale One-Way Semi-Precast Concrete Slabs with Varying Sizes and Shear Connectors
No full textThis study investigates the structural performance of semi-precast concrete slabs (SPCSs), an innovative hybrid construction system that integrates factory-produced precast concrete units with a cast-in-place (CIP) concrete topping to create a composite structural element. This system offers notable advantages in terms of construction acceleration, improved quality control, and reduced labor requirements, as the precast unit serves as both a load-bearing component and a permanent formwork. To evaluate the structural behavior of the SPCSs, an experimental program was conducted on seven full-scale, one-way slab specimens with varying span lengths (4.75 m and 6.0 m), precast unit thicknesses (80 mm and 100 mm), and shear connector geometries (rectangular and triangular). A control slab without shear connectors was also tested to establish a baseline for comparison. The results demonstrated that the inclusion of shear connectors significantly enhanced structural performance. Specifically, the ultimate load capacity increased by 186.4%, and the cracking load increased by 220% compared to the control specimen. Rectangular connectors proved more effective than triangular ones in minimizing interface slip and enhancing ductility. The initial stiffness increased by 163.95%, while the energy dissipation capacity improved by 411.35%. Although variations in span length and topping thickness had relatively minor effects, the presence and geometry of shear connectors played a decisive role in ensuring effective composite action. All reinforced slabs exhibited flexural failure modes, indicating strong bonding and interaction between the precast and cast-in-place (CIP) concrete layers, whereas the control slab experienced premature failure due to interlayer debonding. Theoretical equations based on ACI 318-19 were used to estimate the nominal flexural capacities of the hybrid SPCS slabs, showing reliable agreement with the experimental results. These findings demonstrated the importance of shear connector design in maximizing the load-bearing capacity, ductility, and structural stiffness of SPCS systems under both service and extreme loading conditions
Evaluation of Different Rapid Assessment Approaches for Seismic Risk Evaluation of Masonry Structures
No full textMasonry structures hold notable historical and cultural significance but exhibit inadequate seismic performance due to low-strength materials and structural limitations. This paper aims to investigate and prioritize the seismic risk of masonry buildings to support preservation strategies, enhance urban resilience, and contribute to sustainability. To achieve this, different rapid assessment methods were comparatively applied, providing a practical alternative to detailed seismic analysis, which was impractical for large building stocks. This study focused on the masonry structures of Osijek, a city characterized by moderate seismic hazard, where these buildings are vital to the cultural heritage, tourism, and identity of the local community. Risk prioritization was conducted for 105 masonry buildings using data collected through systematic field observations and measurements. Findings indicate that while rapid assessment methods provide valuable insights for identifying vulnerable structures, their sensitivity and applicability vary according to building characteristics and the available data. The comparative analysis emphasizes that some methods are more effective at detecting structural deficiencies, whereas others are more suitable for large-scale screening when resources are limited. The novelty of this study lies in identifying the efficiency and limitations of different rapid assessment approaches, thereby advancing knowledge in seismic risk prioritization and providing guidance for heritage protection and disaster risk reduction
Experimental and Numerical Study on Seismic Performance of Batter Pile Groups in Loose Sand: No subtitle
No full textPile foundations are critical for maintaining structural integrity under seismic loading, and batter piles, being inclined elements, offer enhanced resistance to combined vertical and lateral forces compared to conventional vertical piles. The objective of this study is to investigate the seismic performance of negative and positive batter pile groups in loose sand. The research employed experimental and numerical approaches: shaking table tests were conducted on 3×3 pile groups embedded in sand with a relative density of 31.2%, subjected to the El Centro and Kobe earthquakes, while finite element modeling was performed to validate the experimental outcomes. The analysis compared the responses of piles with batter angles of -5°, 0°, and +5° in terms of lateral displacement, vertical displacement, and acceleration. Findings revealed that negative battering substantially amplifies pile group displacements, as demonstrated by a 22.085% increase in maximum lateral displacement and a 23.061% rise in vertical displacement for the El Centro motion when the batter angle shifted from 0° to -5°. Conversely, positive battering reduced displacements by up to 4.765%. The novelty of this work lies in experimentally and numerically quantifying the seismic drawbacks of negative battered piles, thereby providing new insights for optimizing pile group design in seismic regions
On the Use of a Confined Sand Cell to Dampen Induced Machine Vibration in a Stabilized Clay Numerical Study
No full textEnvironmental vibrations produced often by industrial and construction processes can affect adjacent soils and structures, sometimes resulting in foundation failure and structural damage. The application of confined cells under foundations as a mitigation technique against dynamic sources, such as generators, is investigated in this study. Numerical models were developed using Plaxis 3D software to simulate the effect of a vibrating source on a circular footing, both with and without confined cells filled with sand soil at varying depths and diameters. In these cells, the soil modeling considered compaction loads typical in actual construction conditions. Results indicate that placing a minimum-diameter cell closer to the foundation with adequate penetration depth can significantly enhance dynamic response and reduce subgrade deformation. The effectiveness of confined soil in minimizing displacement amplitude in the foundation is evaluated, revealing an impressive 86% reduction with specific cell dimensions (Hc/D = 0.50 and Dc/D = 1.15). Moreover, peak particle velocity and excess pore water pressure at monitored points in the surrounding environment experience reductions of 62% and 87%, respectively, demonstrating substantial vibration attenuation. The study does effectively highlight the novelty of the confined sand cell approach, positioning it as a more targeted, efficient, and cost-effective alternative to existing methods, especially for conditions where large-scale, deep vibrations are a concern. Doi: 10.28991/CEJ-2025-011-01-018 Full Text: PD
Gray Correlation Coefficient Analysis on the Mechanical Properties of Nylon Fiber Reinforced Recycled Aggregate Concrete with GGBS
No full textRapid urbanization and infrastructure development intensify the demand for aggregate in concrete production. One efficient technique to reduce demolition and construction waste and produce sustainable concrete is using recycled aggregates. However, previous studies on recycled aggregate concrete (RAC) demonstrated that the mechanical characteristics are remarkably affected due to the adhered previous layers of mortar with the aggregate. Incorporating fibers and supplementary cementitious materials (SCMs) in the concrete mix is a common practice that enhances the mechanical characteristics of concrete and ensures sustainability by reducing carbon footprint. Previous studies lack the combination of nylon fiber (NF) and ground granulated blast furnace slag (GGBS), a by-product of the iron industry and treated as solid waste. Moreover, the research regarding the combined effect of the SCMs and fiber needs to cover the sensitivity of these constituents individually, according to statistical analysis. Hence, the main purpose of this research is to deal with the influence of incorporating NF and GGBS on the mechanical properties of concrete where recycled concrete aggregate was used. Moreover, the sensitivity of the properties with the percentage of replacement of binder and volume fraction (Vf) of nylon fiber was assessed using the Gray correlation coefficient. Compressive strength was dropped by around 10% when recycled material was substituted for natural aggregate. In contrast, adding 0.1% nylon fiber and 10% cement replacement with GGBS increased the crushing strength by about 10.9% compared to the conventional mix. In Gray's analysis, flexural toughness ranked higher in correlation with the controlling factors. Considering the environmental sustainability and the synergetic effect of nylon fiber and GGBS on mechanical properties, recycled aggregate is employable in concrete compared with the conventional concrete of natural stone aggregate. Doi: 10.28991/CEJ-2025-011-03-07 Full Text: PD
Critical Construction Readiness Factors for Bridge Projects
No full textEgyptian investment in infrastructure projects is considerable, especially in bridge construction projects that commonly face delays, cost overruns, rework, and poor productivity. A proper construction readiness (CR) assessment can enhance project performance. This study aims to identify the critical factors that impact the CR of bridge projects in Egypt. Through a literature review and a pilot study with ten highly experienced professionals, a list of 43 construction readiness factors (CRFs) was prepared. To quantitatively rank these CRFs and identify the critical ones, a questionnaire was administered through structured interviews with 92 project managers and engineers experienced in bridge construction projects in Egypt. The participants represented the perspectives of contractors, owners, and consultants. A CRF with a normalized mean score greater than or equal to 0.5 was classified as a critical construction readiness factor (CCRF). For these CCRFs, agreement analysis among contractors, owners, and consultants was conducted using the Kruskal-Wallis test. The correlation strength was also investigated using Spearman's correlation. In total, 16 CCRFs were identified, with the top five: verification of underground utility locations, completion of land surveying work, issuance of clear and sufficient construction drawings, adequate geotechnical investigations, and obtaining all necessary permits and approvals from local authorities. This study provides practitioners with critical factors necessary for assessing the CR of bridge projects in Egypt. From an academic standpoint, it enhances understanding of CR, which is rarely discussed. Doi: 10.28991/CEJ-SP2024-010-015 Full Text: PD
Analysis and Development of Surface Distress Index Modified Based on Pavement Condition Index Criteria for Pavement Evaluation
No full textThe surface distress index (SDI) method has been used in Indonesia to assess road conditions, especially for areas with limited access, inadequate equipment, and limited local resources, which cause inaccuracies in the resulting pavement condition assessment. This research aims to develop a more accurate and efficient pavement condition assessment model based on three types of damage: cracks, potholes, and rutting. To generate accurate SDI values, we adopt and modify the deduct value (DV) curve based on the PCI method to determine the corresponding damage weight and the new road condition assessment. Based on the research results, the three modified SDI damage models showed an average accuracy value of 90%, which means that there is a good match between the models and the conditions on the ground, which is reinforced by the analysis of the mean absolute percentage error (MAPE) and root mean squared error (RMSE) values. In addition, the resulting development includes new assessment criteria and parameters, such as customized DV curve models and specific damage equations, condition index, condition rating, and maintenance types. Which in turn can support more effective and efficient infrastructure management and maintenance. Doi: 10.28991/CEJ-2025-011-01-014 Full Text: PD
High Initial Concrete Compressive Strength with Variations of Superplasticizer and Silica Fume Additions
No full textConcrete is one of the construction materials resulting from a combination of cement, fine aggregate, coarse aggregate, and water, which are mixed into a solid mass and then can be added with minerals (additives) or chemical additives (admixtures). The purpose of this study is to produce high-quality concrete that is optimum at the early age of the concrete so that the concreting time can be shortened, including by adding superplasticizer as a filler and silica fume as an accelerator. This research method involves making a cylindrical test object with a diameter of 15 cm and a height of 30 cm. Then, the concrete mixture is added with silica fume brand Sika Fume and superplasticizer brand Sika Concrete produced by PT. Sika with 19 variations of the mixture composition; the compressive strength test of the concrete is carried out at 3 days, 7 days, and 28 days. The findings are that 75% of concrete samples using additional materials in the form of silica fume and superplasticizer are quite significant in increasing the initial compressive strength of the concrete by up to 30% both at the age of 3 days, as well as at the age of 7 days and 28 days. The use of additional materials in the form of silica fume and superplasticizer in concrete mixtures with the right levels can generally improve the quality of concrete in its initial compressive strength at the age of 3 days or its workability or fluidity. However, silica fume and superplasticizer materials, when entered into concrete, have mutually influenced performance. The innovation is that high-quality concrete that is optimum at an early age of concrete can be done easily and cheaply using materials that are easily found in the field by combining superplasticizer as a filler and silica fume as an accelerator. Doi: 10.28991/CEJ-2025-011-01-07 Full Text: PD