2031 research outputs found
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A Novel Approach to Detect Parking Space Occupancy for Efficient Urban Management
Get PDFObjectives: This study aims to develop A Novel Approach to Detect Parking Space Occupancy for Efficient Urban Management utilization and enhance user experience with real-time, accurate data. Methods/Analysis: The proposed system detects the parking space occupancy for efficient urban management by using a Multi-Component Attention Graph Convolutional Neural Network (DPSO-MCAGCNN) and processes data from the PKLot dataset. Pre-processing is performed using the Maximum Correntropy Quaternion Kalman Filter (MCQKF) for normalization. Key features like area, perimeter, and aspect ratio are extracted using the Second-Order Time-Reassigned Multi synchro squeezing Transform (SOTRMT) and analyzed through MCAGCNN. The Leaf-in-Wind Optimization (LWO) technique is incorporated to optimize the MCAGCNN for higher accuracy. Findings: The proposed system achieves significant improvements over existing methods, including 27.84%-29.27% higher accuracy, 25.87%-29.84% improved R², and 16.27%-19.84% reduced Mean Squared Error (MSE). Evaluation metrics such as RMSE, MAE, and MAPE confirm its robust performance. Novelty/Improvement: The integration of LWO into MCAGCNN enhances optimization and precision, surpassing the performance of state-of-the-art methods like EUPE-SVM, RTPM-YOLOv5, and MASP-LSTM, making it an innovative solution for intelligent parking management. Doi: 10.28991/CEJ-2025-011-02-015 Full Text: PD
Strength, Water Porosity and Sulfuric Acid Performance of Coconut Fiber Reinforced High-Strength Concrete
Get PDFThis study investigates the use of coconut fibers (CFs) derived from coconut husks to enhance the performance of high-strength concrete (HSC), aligning with sustainability goals through the reuse of agricultural waste. The objective was to assess the strength properties, water porosity, and sulfuric acid resistance of coconut fiber-reinforced high-strength concrete (CFR-HSC), targeting a mean compressive strength of 60 MPa. CFs underwent an alkali treatment involving boiling for one hour followed by immersion in a 1% sodium hydroxide (NaOH) solution, which improved their surface morphology as confirmed by scanning electron microscopy (SEM). Concrete specimens with CFs contents of 0.25, 0.5, 1.0, 1.5, and 2.0% were evaluated. Increased CF contents content reduced workability and dry density, while compressive strength at 7 and 14 days improved by 2.31 and 13.02%, respectively, at 0.5% CF content but showed no significant improvement at 28 days. However, tensile and flexural strengths improved significantly, achieving the highest gains of 34.71 and 7.03% at 1% CF content, respectively. CFR-HSC exhibited increased water porosity but enhanced resistance to sulfuric acid, indicating improved durability under aggressive environments. These findings demonstrate the potential of NaOH-treated (NT) CFs to enhance tensile and flexural properties while improving chemical durability, offering a sustainable approach to advancing HSC performance. Doi: 10.28991/CEJ-2025-011-04-023 Full Text: PD
Integrated FEM, CFD, and BIM Approaches for Optimizing Pre-Stressed Concrete Wind Turbine Tower Design
Get PDFToday, all over the world, people are looking for sustainable energy with modern systems for the coming generations. Wind energy plays a crucial role in supplying electricity to modern systems worldwide. Onshore turbines are necessary to ensure efficient and economical operation of taller wind towers, which can reach up to 100 m. However, building taller turbine towers faces many challenges, such as complex cross-sectional design, multiple stresses, and high construction costs due to different variables. To combat these challenges, this article proposes an optimization design aimed at enhancing the cost-effectiveness of the pre-stressed concrete wind turbine industry, making it accessible to the wind turbine market and design engineers. The main idea of the research is an integration of design criteria and cost conditions by creating a C# plugin to determine the optimal design with minimum cost as an add-in to a 3D software simulating program. This integration helps to calculate computational fluid dynamics (CFD) using the finite element method (FEM) and minimizes costs in building information modeling (BIM), which covers some gaps from the previous works. The study presents a methodology for designing concrete wind towers and facilitating data exchange between finite element software (Ansys) and BIM software by IFC files. The optimization problem in this article is a multi-objective problem, with an optimal design that minimizes costs by reducing the vibrational wear satisfied by suitable structural stiffness. Results showed an optimal design for the concrete wind tower, resulting in a 24% reduction in material costs for the same height compared to conventional alternatives. Doi: 10.28991/CEJ-2025-011-02-08 Full Text: PD
Experimental and Numerical Analysis of Punching Shear of GFRP-RC Slabs
Get PDFThis study investigates the punching shear behavior of Glass Fiber-Reinforced Polymer (GFRP)-reinforced concrete slabs, addressing critical gaps in current design guidelines for high-strength concrete (HSC). The objective is to evaluate the impact of concrete strength, including normal-strength concrete (NSC, 30 MPa) and HSC (60 and 90 MPa), on the punching shear resistance, bridging the lack of experimental data that limits the use of HSC in FRP-reinforced slabs. The research employs experimental testing on three full-scale slab specimens (1.5 m í— 1.5 m í— 0.1 m) under concentric monotonic loading until failure, coupled with Finite Element Analysis (FEA) using the Concrete Damage Plasticity (CDP) model in ABAQUS. Key findings reveal that increasing concrete strength moderately enhances punching shear resistance by 5.6% and 8.9% for 100% and 200% strength increases, respectively. The FEA model successfully replicates load-deflection behavior, crack patterns, and failure mechanisms with less than a 3% deviation from experimental results. This study enriches the literature with experimental data on GFRP-reinforced slabs using HSC and verifies FEA as a robust design tool for engineers. The findings contribute to developing comprehensive design guidelines for FRP-reinforced slabs subjected to punching shear in high-strength applications. Doi: 10.28991/CEJ-SP2024-010-017 Full Text: PD
Dynamic Analysis of MICP-Stabilized Soil and Liquefiable Soil With Varying Salinity Levels
Get PDFThis study investigates the liquefaction potential of soils at Yogyakarta International Airport (YIA), a high-risk seismic zone, and evaluates the efficiency of carbonate precipitation driven by microbial activity (MICP) stabilization under varying salinity situations. The purposes include understanding the dynamic response of natural and MICP-treated soils to seismic loads and assessing the role of salinity in soil behavior. Triaxial cyclic testing was conducted on remolded soil samples at a very loose density (Dr = 10%) to simulate field situations, using Bacillus Safensis. Microbes and a biocementing procedure enhanced with 35% fly ash. Salinity levels of 0%, 1%, 2%, and 3.4% were tested by curing for 28 days. The outcomes reveal that untreated soils liquefied inside of 4–6 cycles at ru = 0.8 for 0%, 2%, and 3.4% salinity. In contrast, 1% salinity delayed liquefaction to 14 cycles, thereby enhancing soil resistance. MICP-treated soils showed enhanced stiffness, decreased compressive strain, and extended resistance to liquefaction under dynamic loads. SEM and XRD analyses verified CaCO3deposition, particle bonding, and decreased pore space. The novelty lies in demonstrating the significant role of salinity in enhancing the MICP procedure and improving soil stability, providing a sustainable solution for mitigating liquefaction risks in saline coastal regions. Doi: 10.28991/CEJ-2025-011-04-010 Full Text: PD
Performance Evaluation of Alkaline Activated Geopolymer Binders Using RCA and Industrial By-Products as Cement Alternatives
Get PDFThis study explores the performance of alkaline-activated geopolymer binders using industrial by-products and recycled concrete fine aggregate (RCFA) as sustainable alternatives to traditional cement. Materials such as granulated blast furnace slag (GBFS), silica fume (SF), red brick powder (RBP), quick lime (QL), and RCA were utilized to develop eco-friendly binders with enhanced mechanical and durability properties. Experimental tests evaluated physical, mechanical, and microstructural characteristics, including setting times, dry density, flexural strength, and compressive strength. Advanced analysis with SEM and EDAX examined aggregate-binder bonding. Results highlighted the critical role of binder composition in determining performance. Balanced mixtures of GBFS, SF, and RBP achieved superior strength, durability, and compact microstructures, while excessive QL increased porosity, reducing effectiveness. Optimal flexural strength (4.24 MPa at 56 days) was observed for the G30/S40-L20 formulation, underscoring the importance of precise proportions. Composition influenced setting times, with SF delaying gelation and high QL content accelerating it. The findings demonstrate the viability of using RCFA and industrial by-products in sustainable construction, offering a pathway to reduce reliance on traditional cement. The study emphasizes optimizing binder formulations for strength and durability while addressing environmental impacts, encouraging further research into long-term performance under diverse conditions. This innovative approach highlights the potential for integrating recycled and industrial by-products into construction practices to achieve eco-friendly solutions and promote sustainable urban development. Doi: 10.28991/CEJ-2025-011-02-018 Full Text: PD
Investigation of an Innovative Technique for R.C. Square Footing Reinforced by GFRP and BFRP Bars with HSC
Get PDFThe utilization of alternate reinforcement materials to improve footing capacity performance has garnered significant interest in recent years. Limited research has been conducted to understand the impacts of basalt reinforcement. This study aims to investigate the performance of the high-strength concrete (HSC) footing reinforced by alternative materials such as glass fiber-reinforced polymer (GFRP) bars and basalt fiber-reinforced polymer (BFRP) bars. This work contains experimental and finite element (FE) numerical modeling aimed at investigating the behavior and crack propagation of HSC footings. Axial load investigations were conducted on RC square footings with cross sections of 300í—300í—90 mm for different materials in reinforcing the RC footing, and an experimental investigation of mechanical properties has been carried out. The main reinforcement for the footing has been varied. Two types of material, namely, glass fiber-reinforced polymer (GFRP) bars and basalt fiber-reinforced polymer (BFRP) bars, were used. Four types of concrete mixture were used: normal concrete (NC), high-strength concrete (HSC), glass fiber-reinforced concrete (GFRC), and HSC+ glass fiber bristles. The experimental results demonstrated an improvement in the ultimate load by 28-49% and an enhancement in performance represented in the cracking pattern. Additionally, a 3D nonlinear finite element (FE) analysis utilizing Abaqus software was conducted to verify the numerical results with experimental findings; the results proved the suitability of the employed experimental setup. Doi: 10.28991/CEJ-2025-011-04-017 Full Text: PD
Manholes Detecting and Mapping Using Open-World Object Detection and GIS Integration
Get PDFAccurate detection and mapping of manholes are essential for urban infrastructure management, facilitating efficient maintenance and safety. This paper introduces a novel methodology that integrates the open-world object detection model, Grounding DINO, with geographic information systems (GIS) to detect and geolocate manholes in urban environments. Unlike traditional object detection approaches that rely on extensive labelled datasets and predefined object categories, Grounding DINO, a transformer-based model, leverages natural language processing for adaptable, scalable detection. Grounding DINO processes natural language descriptions to detect the manholes in an open-world context, overcoming the limitations of predefined object categories. Detected manholes are localized using multi-view triangulation, which refines their 3D positions by leveraging redundant camera viewpoints and intrinsic calibration parameters, which ensures accurate geometric mapping of manhole centers. The resulting geospatial coordinates are transformed into the WGS84 system using a global navigation satellite system/inertial navigation system (GNSS/INS) for compatibility with GIS platforms. The proposed approach achieved sub-meter precision, with mean localization errors of 0.36 meters in easting and 0.34 meters in northing, evaluated on KITTI dataset sequences under various urban conditions. The seamless integration of object detection and geospatial mapping demonstrates the potential of this approach for efficient and scalable urban infrastructure management. Doi: 10.28991/CEJ-2025-011-04-07 Full Text: PD
Microstructural Attributes for Soft Soils Affected by Salts During Soaking and Seepage
Get PDFThis study investigates the impact of salts on the microstructure of natural soft soil under water soaking and seepage conditions over specific periods, comparing results to the natural soil in dry state. The soil sample was taken from a study area in central Iraq, south of Babylon Governorate. The research utilizes scanning electron microscopy (SEM) to analyze soil structure changes. The findings reveal that soaking has a slow effect on salt dissolution, gradually altering the soil's chemical composition and reducing its cohesion. In contrast, seepage accelerates salt removal, with dissolution beginning around 7 days and nearing completion by 30 days. Seepage also has a more evident effect on soil cohesion and bearing capacity compared to soaking, suggesting that improved drainage systems are crucial to prevent rapid soil degradation. SEM results further show that soaking weakens soil structure, increases porosity, and causes general degradation. Seepage causes an irregular cohesion and gradual deformation, which significantly affects soil stability under varying loads. This study provides novel insights into the effects of salt dissolution on soil behavior under different conditions, pointing out the need for better soil management in areas with saline soils. Doi: 10.28991/CEJ-2025-011-05-04 Full Text: PD
Performance Optimization of Masonry Mortar with Marble Dust, Spent Coffee Grounds, and Peanut Shell Ash
Get PDFThis research focused on the inclusion of spent coffee grounds (SCGs) and peanut shell ash (PSH) as variable additives and marble dust as a constant additive to cement materials to substitute aggregates and determine the effect of each variable on the properties of cement materials. To determine the influence of PSH and SCGs, these were added to mortar in 0.1, 0.2, and 0.3% proportions and were combined with microsilica and superplasticizer. To analyze the results, the compressive and flexural strengths during three-point bending were investigated. The chemical composition and microstructure of the mortar mix were investigated using Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray (EDX) spectroscopy. The results showed that incorporating microsilica into the mortar mix increased the compressive strength to over 35.42 MPa compared to the control sample's 33.4 MPa. Adding 0.1% and 0.3% of SCGs and PSH improved the compressive strength of the mortar mix to over 39.48 and 38.09 MPa, respectively. Including 0.2% SCGs and 0.1% PSH increased the flexural strength to over 4.52 and 6.0 MPa, respectively. The SEM and EDX results showed that adding 0.3% SCGs slowed down the formation of calcium silicate hydrates (C-S-H), consequently slowing down the hydration processes, and the strength gain was slower compared to microsilica. The addition of 0.3 PSH stimulated the formation of C-S-H, additionally supplying the cement matrix with such elements as Si and Al. Overall, adding SCGs and PSH has a positive effect on the mechanical and chemical properties of the mortar mix, although adding PSH is more beneficial than adding SCGs. Doi: 10.28991/CEJ-2025-011-03-09 Full Text: PD