Abstract
The fundamental issue with steel-reinforced concrete constructions is corrosion of the steel bars, which finally leads to the structure's collapse and disintegration. Fiber-reinforced polymer (FRP) bars have been widely used in civil engineering used as a substitute for steel reinforcement because it has many advantages such as high strength, light weight, and no corrosion. Moreover, productive technology is becoming more and more mature and industrialized so FRP has become one economic and competitive structure material. Based on the recent research: this paper mainly introduces progress in the studies on concrete structures reinforced with steel or GFRP bars. The contents of this review research article include the cracking/fracture/cracking monitoring of Steel and GFRP reinforced concrete beams in flexure is investigated in the past few years in the world. The possibility of employing Acoustic Emission (AE) and Digital Image Correlation (DIC) to monitor micro and macro cracks generated in reinforced concrete beams will be investigated in this work so that a practical application can be presented. Finally, the integrated technique delivers complimentary information from 'the ear' with the AE and 'the eye' with the DIC.
Key Words
acoustic emission; crack widths; digital image processing; hits; steel and GFRP bars
Address
Gaurav Sharma: Department of Civil Engineering, Lingayas Vidyapeeth, Faridabad, Haryana-121002, India
Payal Sachdeva: Department of Civil Engineering, Chitkara University, Rajpura, Punjab-140401, India
Divyashree Yadav: Dean of Studies, Techno strut, gurgaon, Haryana-121003, India
Abstract
Internal Curing in recent years is one of the special topics in achieving optimal mechanical properties and durability in self-compacting concrete. The use of superabsorbent polymers with the ability to absorb and release water in the hydration process in internal curing has fewer performance limitations. Due to environmental considerations and the lack of drinking water in the world, the use of seawater in construction, including concrete Structures and curing of bulk, high-performance and self-compacting concrete has been the subject of recent research. The present study investigates the effect of using superabsorbent polymers and seawater in the internal curing of self-compacting concrete. Two types of superabsorbent polymers with two different amounts have been used in this research. In order to evaluate the mechanical properties and durability of internally cured concrete samples, compressive strength, electrical resistance, water penetration under pressure, freeze-thaw cycles, and microstructure tests were used in this research. The results showed that the compressive strength of samples made and cured with seawater and superabsorbent polymers increased by over 10%. Examining the results of the electrical resistance test on the samples cured using potassium-based super absorbent polymers also shows the greater effect of internal curing in the process of obtaining resistance and completing the hydration. The increase in electrical resistance as a result of internal curing using potassium-based superabsorbent polymer with amounts of 0.2% and 0.3%, compared to sodium, was 25.5% and 19.9%. Internal curing using seawater and potassium-based superabsorbent polymer caused a reduction of over 40% in the test of water penetration compared to sodium-based superabsorbent polymer. Investigation of microstructure results obtained from SEM, XRF, and XRD experiments, showed an increase of
8.1% and 6.2% in final products of the hydration process when using potassium-based superabsorbent polymer.
Address
Azim Savaripour, Ali Karbakhsh and Mohsen Mohammadizadeh: Department of Civil Engineering, Sirjan-Branch, Islamic Azad University, Sirjan, Iran
Amir A. Hedayat: Department of Civil Engineering, Kerman-Branch, Islamic Azad University, Kerman, Iran
Abstract
This research aims to assess the structural efficiency of reinforced concrete beams with casting joints made of GFRP bars that are longitudinally reinforced and CFRP sheets added to the system. The focus is mainly on the effects of casting discontinuities at strategic locations, such as the shear and flexural regions, that may significantly affect the structural strength. To determine the initial hardening time, the effect of retarding plasticizers on hardening on the initial setting time and mechanical properties of concrete was studied. Then, seven beams made of high-strength concrete were cast and subjected to failure testing in the initial phase of the study, two beams reinforced with GFRP bars and three with conventional steel reinforcements have a cold joint. The third stage involved casting two more beams with GFRP and having cold joints at the flexural zone, representing the most critical scenario similar to previous beams reinforced with CFRP sheets placed in different configurations. The results show risks in concrete beam have joint at flexure or shear zone due to delayed casting that the lowest failure value for beam reinforced longitudinally with GFRP bars have cast-joint was 23.6 kN a decreasing till 46% due to weak efficacy GFRP bars at joint. So, for these beams must be strengthened by the CFRP layers. The effect of the CFRP layers was improved a behavior of these beams. The strengthened of these beams reinforced longitudinally with GFRP bars have joint at mid by using CFRP sheets was increased a load capacity about 111% to 118%. This paper provides new information about CFRP sheets debonding at the casting joint was after concrete crushing in the compression zone. According to the results, CFRP strengthening is a good way to increase load capacity and reduce the flaws that casting joints introduce. Generally, this study endeavors to yield novel insights into the behavior of such composite systems to enhance concrete beams have cold joints.
Address
Thaer Jasim Mohammed and Saadiyah M. Ismael: Department of Civil Techniques, Institute of Technology/ Baghdad, Middle Technical University, Baghdad, Iraq
Sabreen Ali Abed: epartment of Architectural Engineering, College of Engineering, University of Mosul, Mosul 41002, Iraq
Abstract
Sandwich structures with Carbon Fiber Reinforced Polymer (CFRP) skins are being utilized in construction applications where impact loading is a critical concern. Incorporating foam into the core layer is a promising strategy to enhance structural stability and integrity under impact conditions. However, the geometry, material properties, and assembly of the foam layer significantly affect the energy absorption capacity of such structures. In conventional foam-based sandwich structures, while the inclusion of foam reduces the risk of catastrophic failure under impact, it often results in partial permanent deformation. To address this limitation, this study introduces an innovative Foam-Based Sandwich Panel (FBSP) with laminated layers made of CFRP as the skins, and Shape Memory Alloy (SMA) strips, termed SMA-FBSP. The SMA-FBSP integrates high-density foam in the core for enhanced energy absorption and embeds SMA strips to enable shape recovery after the structure being deformed due to impact load. Low-velocity impact and repetitive impact testing were conducted to simulate real-world scenarios and evaluate the performance of the SMA-FBSP. A proof-of-concept prototype was fabricated, demonstrating the capacity of the structure in shape recovery under low-velocity impact loading. The presence of SMA strips enable the sandwich panel to regain its original shape for low strain. However, at high strain, (~10%), the SMA-FBSP regained approximately 80% upon releasing the applied load. The induced strain is measured by an array of surface bounded Fiber Bragg Grating (FBG) sensor. This advancement highlights the potential of SMA-FBSP in applications requiring both high impact resistance and structural recovery.
Key Words
damping; energy absorption; foam core; laminated composite; low-velocity impact; sandwich panel; shape memory alloy; shape recovery; vibration
Address
Abolghassem Zabihollah, Rajesh B. Vuddandam and Elisha S. Acquah: Department of Mechanical, Environmental, and Civil Engineering, Tarleton State University, Stephenville, USA
Abstract
Efficient routing of multi-compartment vehicles is a critical challenge in logistics, as it involves optimizing travel distance and load distribution while considering multiple constraints. Traditional vehicle routing algorithms often fail to address the complexities of compartmentalized cargo, leading to inefficiencies in delivery operations and increased costs. This study aims to bridge this gap by introducing a Three-Dimensional Ant Colony Algorithm (3D-ACA) for optimizing Multi-Compartment Vehicle Routing (MCVR). This research aims to minimize total travel distance while ensuring proper allocation of goods to vehicle compartments and adherence to delivery time constraints. The approach involves formulating the Multi-Compartment Vehicle Routing Problem (MCVRP) as an optimization model and applying 3D-ACA to generate efficient routing solutions. Unlike conventional methods, which primarily focus on shortest-path algorithms, this study incorporates three key factors, route efficiency, compartment constraints, and time windows, into a single optimization framework. The novelty of this research lies in the three-dimensional adaptation of the ant colony algorithm, which extends the standard routing problem to include compartment-based decision-making. This approach provides a more realistic and practical solution for logistics companies aiming to improve fleet utilization, reduce costs, and enhance operational efficiency. The proposed 3D-ACA significantly improved key performance metrics, including a 15.6% reduction in travel distance compared to Ant Colony Optimization (ACO), up to 17% lower operational costs, and over 95% feasibility rates across datasets. It also demonstrated superior scalability by solving large-scale problems (150 nodes) under 45 minutes, outperforming traditional methods such as GA and MIP in efficiency and constraint satisfaction.
Key Words
compartment constraints; logistics and operational efficiency; Multi-Compartment Vehicle Routing Problem (MCVRP); optimization model; route efficiency; Three-Dimensional Ant Colony Algorithm (3D-ACA)
Address
Khidhair Jasim Mohammed: Air Conditioning and Refrigeration Techniques Engineering Department, College of Engineering and Technologies, Al-Mustaqbal University, 51001 Hilla, Babylon, Iraq
José Escorcia-Gutierrez: Department of Computational Science and Electronics, Universidad de la Costa, CUC,
Barranquilla, 080002, Colombia
Yousef Zandi: Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran
A. Sadighi Agdas: Ghateh Gostar Novin Company, Tabriz, 51579, Iran
Hamid Assilzadeh: Institute of Research and Development, Duy Tan University, Da Nang, Viet Nam;
Faculty of Civil Engineering and Mechanics, Jiangsu University, 301 Xuefu Rd, Zhenjiang,
Jiangsu 212013, China
Amr Alalawi and Hakim AL Garalleh: Department of Mathematical Science, College of Engineering, University of Business and Technology, Jeddah 21361, Saudi Arabia
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