The last blog described the universal problem affecting the RCC which is corrosion / rusting and what are the causes of corrosion. In order for a Reinforced structure to have corrosion, the presence of these two components is needed which is moisture and air. Usually, corrosion starts out slowly and results in severe damages which in turn affects the structural integrity of the building.
Thermo Mechanically treated steel bars created the current standard of reinforcement. Their excellent tensile strength and ductility make them ideal and preferred for construction of building structures. Building structures are always susceptible to environmental changes. No building will ever be the same once the environmental changes kick in. Out of all the changes, the most serious and devastating is corrosion.
Steel has been used for many decades by many civilizations for building structural and engineering purposes, they have continued prove very effective in both land and marine environments due their unique combination of mechanical properties which gives them natural protection against natural variables. Where steel stumbles as the ultimate building block is with its corrosion by various environmental actions. When it comes to modern construction, generally, the concrete mix is reinforced by steel bars in the case of the common RCC structures.
It is expected that in construction there will become unexpected surprises and in one of those many unexpected surprises not many of the same long-term effects as the need to bend TMT bars. Bending TMT bar is a tricky skill, there are some obvious downsides such as broken TMT bars. The long-term negative effects come from the breaking of the protective film from the surface of the TMT bars. These films are coats of special paints which does rust or corrosion to happen. This happens as TMT bars have a strong shell and a soft inner core, while outer shell can withstand rust and corrosion for a long long time as they come prepared with a protective coating.
An average homeowner or even more accurately an average person will be shocked to learn that India spends more money on fighting rust than on education. According to Sunil Duggal of Hindustan Zinc Ltd (HZL), “India loses around 4-5 percent of GDP annually on account of corrosion losses.” India currently spends around 3.8% of its GDP on education. Even if a nation can live this situation, an average homeowner doesn’t need to live like this.