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Item A Review on Mechanical and Microstructure Properties of Reinforced Concrete Exposed to High Temperatures(Springer, 2021) Goudar, S.K.; Santhosh, S.K.; Das, B.B.This paper presents the recent research progress on the response of concrete exposed to fire or high temperatures. The main highlight of this review paper is a compilation of previously reported data regarding the variations in mechanical properties and microstructure properties of concrete when exposed to high temperatures. The concrete structures get deteriorated at the macro- and microscopic levels due to high-temperature exposure. The macro-level damages can be measured with degradation in mechanical properties such as the reduction in compressive strength, weight loss, changes in elastic properties, reduction of bond strength in reinforced concrete, etc. The macro-cracks on the surface of concrete causes spalling which can be observed after exposing the concrete samples to more than 300 ℃. The compressive strength of the concrete reduces slightly till 400 ℃, and when the temperature increased to 600 ℃, there was an exponential reduction in the compressive strength of concrete. Another important parameter is bond strength degradation, which plays a crucial role in durability issues. To understand the deterioration phenomenon and changes in mechanical properties, the changes at the level of the microstructure of concrete need to be understood. Dehydration of products causes deterioration of mechanical properties and weight loss of concrete when exposed to high temperatures. At different temperatures, the microstructure changes and the response of hydration products such as calcium hydroxide (CH), CSH gel, unhydrated cement and capillary water reported by previous researchers are compiled and discussed. © 2021, Springer Nature Singapore Pte Ltd.Item Processing techniques of recycled aggregates(Elsevier, 2025) Trivedi, S.S.; Das, B.B.; Barbhuiya, S.Three essential components of every modern-day growth are preservation of natural aggregate resources, green construction, and the safeguarding of the environment. One such endeavor is the incorporation of recycled aggregate (RA) in concrete. Because of the issues with its strength and durability, the use of RA is typically limited to inferior load constructions. With appropriate management and effective processing methods, the application can be expanded to high-strength concrete. In the present manuscript, the current C&D waste management practices adopted by various nations are highlighted alongside different in-action legislations are thoroughly reviewed for developing an understanding about the basic elements involved in the debris management. In addition, some of the latest and novel recycling approaches are investigated such as autogenous cleaning method, air and hydraulic jigging technologies, and advanced dry recovery system. To investigate the nature of RA processed from aforementioned technologies, the inherent properties of aggregates such as specific gravity, water absorption, density, and abrasion values alongside microstructure performance through scanning electron microscopy (SEM) are comprehensively reviewed and presented. Based on the extensive investigation, it is recognized that effective C&D waste management can be accomplished using certain techniques such as circular procurement and green construction. Furthermore, there is a requirement for specified processing methods that enhances the physio-chemical properties. Also, the surface morphology can be improved using combined crushing and ball milling approaches. Overall, it is recommended to implement vertical shaft crushing and ball milling for the development of fine RA whereas for the coarse RA fractions, multistage jaw crushing and advanced dry recovery (ADR) system are some of the finest processing approaches. © 2025 Elsevier Ltd. All rights reserved.