• Lakhminarayanan S
• mohana prasath D
• Nitthyasri K S
• Praveen Kumar P
• Ramya Devi M

Thermo-Mechanically Treated (TMT) steel bars play a vital role as reinforcement materials in concrete structures due to their superior strength, ductility, and durability. These bars undergo a special thermomechanical treatment process that creates a hard outer martensitic layer and a softer inner core, resulting in an ideal balance between strength and flexibility. Such properties make TMT bars highly suitable for various construction environments, including harsh and aggressive conditions. However, exposure to corrosive environments, especially water containing elevated levels of Total Dissolved Solids (TDS), poses a considerable threat to the mechanical performance and longevity of TMT bars. High TDS levels often indicate the presence of salts such as chlorides, sulphates, and other minerals, which accelerate corrosion processes. Corrosion not only weakens the steel by reducing its crosssectional area through rusting but also adversely affects the bond between steel and concrete, leading to compromised structural integrity and eventual failures. This research comprehensively investigates the tensile performance of TMT bars of different diameters (6mm, 10mm, 12mm, 16mm, and 20mm) made by three leading brands in India, exposed to varying water TDS levels of 60 ppm (low), 700 ppm (moderate), and 4000 ppm (high). The study employs tensile testing using a Universal Testing Machine (UTM) to measure key mechanical properties such as Ultimate Tensile Strength (UTS) and elongation at break, which reflects ductility and deformation characteristics under stress. To validate and understand the underlying mechanical behaviour, microstructural examinations are conducted, revealing changes such as pitting, formation of corrosion products, and alterations in the martensitic and ferrite-pearlite phases of the steel. These microstructural changes correlate with the observed tensile properties, explaining the degradation trends due to corrosion. The study’s findings provide valuable data enabling engineers and construction professionals to make informed decisions when selecting reinforcement materials, especially in environments prone to high TDS exposure such as coastal areas, groundwater with high mineral content, or industrial sites. By understanding the impact of water quality on TMT bar durability and performance, it is possible to optimize construction design for enhanced safety and cost efficiency, ultimately extending the service life of reinforced concrete structures.

Steel corrosion resistance, Microstructural examination, Ultimate tensile strength, Tensile properties, Total Dissolved Solids

"COMPARITIVE STUDY OF TENSILE PROPERTIES OF TMT BARS IMMERSED IN WATER WITH VARYING TDS LEVELS: BRAND ANALYSIS AND COST ASSESSMENT", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 11, page no.f126-f136, November-2025, Available :http://www.jetir.org/papers/JETIR2511539.pdf

"COMPARITIVE STUDY OF TENSILE PROPERTIES OF TMT BARS IMMERSED IN WATER WITH VARYING TDS LEVELS: BRAND ANALYSIS AND COST ASSESSMENT", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 11, page no. ppf126-f136, November-2025, Available at : http://www.jetir.org/papers/JETIR2511539.pdf