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Research Article
Assessment of Galvanized Iron Fiber and Waste Tire Composite Concrete
Issue:
Volume 13, Issue 3, June 2025
Pages:
116-121
Received:
6 April 2025
Accepted:
15 April 2025
Published:
14 May 2025
Abstract: The traditional method of disposing of tire debris is now a huge worldwide problem and presents serious environmental risks. Because of this, using waste tires in concrete not only lowers its density but also guarantees an economical and environmentally responsible alternative for the building sector. However, because of their superior ductility and tensile strength, galvanized iron (GI) wire fibers are now more frequently used in plain concrete. Different amounts of waste tire fiber (WTF) with different coarse aggregate replacement ratios (0, 3, 6, and 9%) and different percentages of GI fiber (GIF) (0, 1, 3, and 5%) of concrete volume were examined in this study under axial compression in concrete grades M25, M30, and M35 respectively. According to the test results, GI fiber and waste tire composite concrete demonstrated ductile failure behavior in comparison to control concrete, in addition to delaying the propagation of cracks. On the other hand, the workability of concrete decreased as the percentage of mixed fiber increased. In addition, higher-strength concrete's ductility and compressive strength considerably improved as fiber percentages rose in comparison to lower-grade concrete. The specimen that contained 1% GIF and 3% WTF performed the best under peak load conditions for higher-strength concrete, according to the data.
Abstract: The traditional method of disposing of tire debris is now a huge worldwide problem and presents serious environmental risks. Because of this, using waste tires in concrete not only lowers its density but also guarantees an economical and environmentally responsible alternative for the building sector. However, because of their superior ductility an...
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Research Article
Comparative Case Study of RC Frame Using Finite Element Modeling Under NBC 105:2020 and IS 1893 (Part 1):2016
Issue:
Volume 13, Issue 3, June 2025
Pages:
122-136
Received:
4 May 2025
Accepted:
19 May 2025
Published:
20 June 2025
Abstract: Nepal’s high seismic vulnerability necessitates stringent design codes to mitigate infrastructure risks. This study compares a regular reinforced concrete frame under Nepal’s NBC 105:2020 and India’s IS 1893 (part 1):2016 using finite element modeling in ETABS and SAP2000 commercial software, incorporating stiffness modifiers prescribed in the codes. Seismic parameters are compared in both ETABS and SAP2000, and for design forces and reinforcement requirements, only ETABS is used. Seismic analyses employed Equivalent Static and Response Spectrum methods. Results reveal NBC 105:2020 mandates double the base shear compared to IS 1893:2016, with lateral displacements surging by 50.6–66.6% under static analysis and 106–108% under dynamic analysis. Drift patterns mirrored displacement trends, showing similar percentage increases. Double base shear, amplified lateral displacements and drifts, consistent across both software analysis approaches, underscore NBC 105:2020’s heightened design forces and reinforcement demands, particularly in lower floors. For beams, NBC 105:2020 required 12.7% more reinforcement, 11.6% higher moments, 110% lower torsion while maintaining comparable shear forces. Columns under NBC exhibited 79.78% higher axial forces, Floor-wise fluctuation in biaxial moments and 10.6% more reinforcement, with lower floors disproportionately impacted. This study suggests that municipalities and engineers in Nepal to follow the NBC code. While NBC 105:2020’s stricter seismic provisions—requiring more robust structural systems, amplified design forces, and higher reinforcement demands compared to IS 1893 (Part 1):2016—escalate construction costs, its conservative approach ensures enhanced seismic resilience, critical for high-seismic-risk regions like Nepal.
Abstract: Nepal’s high seismic vulnerability necessitates stringent design codes to mitigate infrastructure risks. This study compares a regular reinforced concrete frame under Nepal’s NBC 105:2020 and India’s IS 1893 (part 1):2016 using finite element modeling in ETABS and SAP2000 commercial software, incorporating stiffness modifiers prescribed in the code...
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Research Article
Key Design Technologies of the Taoyuan Jinsha River Bridge in Yunnan
Bin Liu,
Zhong Zhu*,
Yong Fu Huang,
Jian Ma,
Lei Wang
Issue:
Volume 13, Issue 3, June 2025
Pages:
137-151
Received:
14 April 2025
Accepted:
10 June 2025
Published:
22 June 2025
Abstract: The Taoyuan Jinsha River Bridge on the Dali-Yongsheng Expressway is a steel box girder suspension bridge constructed in an extremely complex environment, characterized by: proximity to active fault zones (minimum distance: 100 meters), high seismic intensity (Zone VIII), elevated reservoir water levels, and deep overlying weak strata. Spanning a high mountain gorge, the bridge runs parallel to the Holocene active fault zone with a minimal clearance of 100–150 meters, resulting in exceptionally pronounced seismic effects. To address these extreme conditions, the project pioneered multiple innovative technologies:(1) High-strength steel bars (R40mm HRB500 grade) were first adopted in the tower structure, reducing reinforcement quantities while ensuring stability and lowering construction complexity;(2) Viscous dampers installed at beam ends effectively constrained longitudinal displacement under high-intensity seismic and wind loads, reducing the expansion joint span from 3,200 mm (non-seismic design) to 1,520 mm, significantly cutting costs for bearings and expansion joints;(3) Lightweight flat steel box girders for stiffening girders markedly reduced seismic forces and wind load effects in the reservoir area;(4) 25 mm-thick steel casings in pile foundations decreased reinforcement requirements while mitigating safety risks during pile construction in weak strata.Through integrated seismic mitigation strategies, optimized life-cycle costs generated indirect economic benefits of 31 million yuan.
Abstract: The Taoyuan Jinsha River Bridge on the Dali-Yongsheng Expressway is a steel box girder suspension bridge constructed in an extremely complex environment, characterized by: proximity to active fault zones (minimum distance: 100 meters), high seismic intensity (Zone VIII), elevated reservoir water levels, and deep overlying weak strata. Spanning a hi...
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Research Article
Mechanical Properties of Double-gasketed Steel Joints for Bar-wrapped Cylinder Concrete Pressure Pipe Using Experimental and Numerical Methods
Issue:
Volume 13, Issue 3, June 2025
Pages:
152-164
Received:
25 April 2025
Accepted:
5 June 2025
Published:
22 June 2025
Abstract: Differential settlements of foundation can result in the excessive relative rotation angles between bar-wrapped cylinder concrete pressure pipes (BCCP), which may cause the failure of joint structures. This paper presents experimental and numerical methods for investigating mechanical properties of pipe joints under different relative rotation angles. Four hydraulic jacks were installed below two DN1400 BCCP specimens to induce controlled relative rotation during the experiment. Three types of loading modes were designed to test the structure performance of joints under different loading conditions. Concrete damaged plasticity model (CDPM) and cohesive elements are used in finite element method to simulate the mechanical response of concrete under complex loading, and fracture in bonded interface between concrete and steel cylinder. The results show that the whole failure process of joints can be divided into four stages, that is, the debonding of bell end interface layer, the cracking of spigot end inner concrete core, the debonding of spigot end interface layer and the yielding of steel spigot ring, arranged in the order of failure occurrence. The limit values of different failure stages are variable with the change of prestress loss value, insertion depth, loading modes, pipe types and inner water pressure. All the factors need to be considered in determining the limit values of different stages using experimental and numerical methods to evaluate the failure state of BCCP joint structures in engineering.
Abstract: Differential settlements of foundation can result in the excessive relative rotation angles between bar-wrapped cylinder concrete pressure pipes (BCCP), which may cause the failure of joint structures. This paper presents experimental and numerical methods for investigating mechanical properties of pipe joints under different relative rotation angl...
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Review Article
A Review of the Performance Criteria and Key Design Input Parameters for Jointed Plain Concrete Pavements
Boon Tiong Chua*
,
Kali Prasad Nepal
Issue:
Volume 13, Issue 3, June 2025
Pages:
165-184
Received:
24 May 2025
Accepted:
11 June 2025
Published:
30 June 2025
Abstract: The design of Jointed Plain Concrete Pavement (JPCP) is typically carried out using the total fatigue and/or erosion damage models, based on the requirements outlined in the design brief or the specific practical conditions. The fatigue failure and erosion damage models criteria are widely recognised and used globally to evaluate the performance of JPCP. The performance failure criterion is inherently tied to the design methods, making it unsuitable for direct comparison with other methods in isolation. But the most widely used the mechanistic-empirical design procedure for JPCP is heavily reliant on the calibration of these damage models, which illustrate the relationship between stress ratio (the allowable flexural stress divided by the modulus of rupture) and the allowable number of load repetitions for a specific axle load. The induced flexural stress in the pavement is influenced by numerous factors, including foundation support conditions, axle loads, load locations (interior, edge and corner), design traffic loading, tyre pressure, concrete properties, slab size (with and without concrete shoulders), the ratio of joint spacing to radius of relative stiffness, and other key design parameters. This paper presents an extensive literature review of these key design factors that influence the design of JPCP, with the aim of enhancing the understanding of pavement behaviour and optimising pavement performance for cost-effective designs. The literature review also reveals that erosion distress prediction model developed by Portland Cement Association is based primarily on granular subbase materials which is dated and the benefit of using as non-erodible subbase materials is not incorporated in the performance assessment. Furthermore, the integration of a more robust faulting damage model would require significant advancements, indicating a clear need for further research in this area. The analysis further reveals that the thickness of concrete pavement is relatively insensitive to modest changes in the modulus of subgrade reaction (K). Additionally, it shows that the allowable joint spacing increases with greater slab thickness but decreases as the K-value rises. The average reduction in slab thickness is found to be approximately 12% when concrete shoulders are used in the design. The findings underscore the importance of integrating various design aspects of JPCP, rather than treating them as a series of isolated activities or materials, in order achieve optimal pavement performance.
Abstract: The design of Jointed Plain Concrete Pavement (JPCP) is typically carried out using the total fatigue and/or erosion damage models, based on the requirements outlined in the design brief or the specific practical conditions. The fatigue failure and erosion damage models criteria are widely recognised and used globally to evaluate the performance of...
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