http://suspace.su.edu.bd/handle/123456789/564 Sat, 18 Apr 2026 14:13:07 GMT 2026-04-18T14:13:07Z http://suspace.su.edu.bd/handle/123456789/1706 Ehanching Strength And Drabily Of Concrete Using NANO-CALCIUM Carbonate (CaCO3) AND Sodium D Carbonate (Na2CO3) As Cement Additives Hossen, Md. Kamal This research explores the influence of nano-calcium carbonate (CaCO₃) and sodium carbonate (Na₂CO₃) as cement additives on the compressive strength of concrete, aiming to enhance durability in the saline environments typical of coastal Bangladesh. Three concrete mixes were tested: a control mix (Mix 1) with no additives, Mix 2 with 22 g Na₂CO₃ and 88 g nano-CaCO₃, and Mix 3 with 88 g Na₂CO₃ and 132 g nano CaCO₃. A total of 18 cylindrical specimens (100 mm × 200 mm) were cast, with 9 cured for 7 days and 9 for 28 days, and tested per ASTM C39. At 7 days, the control mix achieved the highest strength at 3584 psi (24.72 MPa), while Mix 2 and Mix 3 showed reduced strengths of 3079 psi (21.23 MPa) and 2650 psi (18.28 MPa), respectively, indicating early hydration challenges due to the additives. However, by 28 days, Mix 2 exhibited a remarkable strength gain, reaching 5198 psi (30.34 MPa)—surpassing the control’s 5120 psi (35.31 MPa)—while Mix 3 remained lower at 3785 psi (26.10 MPa). These findings suggest that while high additive doses (Mix 3) consistently impair strength, a moderate dosage (Mix 2) can enhance long-term performance, likely due to improved hydration and microstructural refinement by nano-CaCO₃. This study provides valuable insights for designing salt-tolerant concrete mixes, offering a practical solution for coastal infrastructure in Bangladesh by balancing early-stage limitations with significant 28-day strength gains. Sat, 19 Apr 2025 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/1706 2025-04-19T00:00:00Z http://suspace.su.edu.bd/handle/123456789/1705 Environmentally Sustainable Utilization Of Recycled Plastic Waste In Bituminous Pavement Tuzzohra, Fatema The disposal of plastic waste has become a critical environmental issue, contributing to pollution and global warming. The Roads and Highways Department of Bangladesh manages over 375,000 kilometers of national, regional, and district roads, with an increasing need for more durable and cost-effective pavement solutions. In response to the environmental challenge posed by plastic waste, a novel approach utilizing recycled plastic in bituminous mixtures for road construction has shown significant promise. The plastic waste, primarily composed of polyethylene, polystyrene, and polypropylene, is shredded, coated over aggregates, and mixed with hot bitumen to create a strong, durable pavement. This not only enhances the properties of bituminous mixtures but also provides a solution to the disposal of plastic waste, reducing environmental pollution. The addition of waste plastic to bitumen improves the stability and strength of the compacted mixtures, as confirmed by Marshal stability tests, which demonstrate better performance compared to conventional mixtures. This technology offers several advantages, including increased resistance to common pavement defects such as potholes, ruts, and cracking, while also enhancing the pavement's durability. Furthermore, the incorporation of titanium dioxide as a smoke-absorbent material helps mitigate vehicular emissions, a significant environmental concern, particularly in Bangladesh’s hot-humid climate. This paper discusses the use of waste plastic in bituminous mixes, focusing on the benefits of the modified binder in enhancing pavement performance, reducing maintenance costs, and promoting sustainable plastic waste management. The study highlights the potential of this innovative technology to revolutionize road construction by addressing both environmental and infrastructural challenges. Keywords: Plastic waste, bituminous pavement, polymer-modified bitumen, waste plastic modified bitumen, environmental sustainability, Marshal stability, pavement durability. Sat, 19 Apr 2025 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/1705 2025-04-19T00:00:00Z http://suspace.su.edu.bd/handle/123456789/1704 Investiegation Of Temperature Impact On Compressive Strength Of Concrete Rashid, Md. Mamunur In this study we are going to discuss about the strength of concrete after heating. Sometime building catches fire. As a result it loses strength. So our aim is to determine the strength of concrete after heat as part of an investigation on the effect of temperature on the crushing strength of concrete, tests have been carried out using 4 in. diameter by 8 in. long specimens made with ordinary Portland cement, Sylhet sand and coarse aggregate, having various mix proportions and water/cement ratios. The crushing strength of concrete at temperatures up to 400°C was independent of the water/cement ratio used but was influenced by the aggregate/cement ratio. Concrete specimens loaded to produce normal design compressive stress during the period of heating showed less reduction in strength than specimens without imposed load. There was a further loss in the compressive strength of the specimens when cooled after heating. Sat, 19 Apr 2025 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/1704 2025-04-19T00:00:00Z http://suspace.su.edu.bd/handle/123456789/1703 Comparative Study of Structural Framing System : Omre , Imre And Smrf In Regular Shape RCC Building Haque, Robiul All structural systems are not treated equally when the response to earthquake-induced forces is of concern. Structural configuration, symmetry, mass distribution, and vertical regularity must be considered. The importance of strength, stiffness, and ductility in relation to acceptable response must also be appreciated. While considering the lateral force resisting systems, we came up with many options to have structural systems like Bearing wall systems, Moment Resisting frames, and Lateral Bracing systems, designing the moment resisting concrete frame structures we have the option to use IMRF, OMRF, or SMRF. The basic step in conceptual design is to find the best suitable framing system and then lateral load-resisting mechanism, while designing structures it is often found to be complicated to make decision of Response Modification Factor (R), which is a measure of ductility and over-strength of the structures. It is used to find the base shear, which is distributed on different stories. SMRF and IMRF are emphasized in the research and a detailed computer simulation of the different RCC structures in Zone-II with different R-values i.e., 5 and 8 given in BNBC-2020 are used. In this study, there are a total of 3 models of different frame systems are developed and several comparisons are made among them, such as drift, displacement, sway, column and beam Size comparison, longitudinal reinforcement requirement comparison, column cost analysis, and base shear comparison. Conclusions are drawn from the study after all the comparison analysis it is found that the SMRF frame system is a better and more effective framing system than the other two framing systems such as IMRF and OMRF. Sat, 19 Apr 2025 00:00:00 GMT http://suspace.su.edu.bd/handle/123456789/1703 2025-04-19T00:00:00Z