Comparison of Indian Standard Specification for Aggregates and Manufactured Sand With International Standards: A Review

Many infrastructure projects are in progress, including highways, metro rail systems, state highway expansions, and airport developments. As these projects advance, new residential areas are being established in metropoli- tan cities, tier-two cities, and near railway metro junctions and airports. The demand for aggregates and sand has increased significantly. Many regions in the country are facing a shortage of natural sand. Manufactured sand is created using waste materials and crushed rocks to counter the issue of lack of natural sand for construction. The IS 383-2016 outlines guidelines regarding the grad- ing and mechanical properties of manufactured sand. This sand experiences hydrothermal and chemical reactions as well as undergoes physical changes when utilized in concrete. Alkali-silica reaction in concrete occurs due to the presence of moisture from surrounding structures, alkalis in cement and silica in aggregates. This reaction can become visible within weeks or even after 10-20 years. Current infrastructure developments including bridges, flyovers and un- derground metro tunnels must be built to last between 50 to 100 years with min- imal maintenance. Using excellent construction materials ensures the durability and longevity of infrastructure. Natural aggregates available near construction sites vary in terms of chemical and physio-mechanical properties. Therefore, revisions are needed in Indian Standards for manufactured sand and aggregates especially for assessment of organic impurities, levels of chloride, alkali-silica reaction and clay content. They should also address the specific requirements of various construction uses. This paper overviews Indian Standards for man- ufactured sand and aggregates in detail. It also compares several other related standards such as Japanese, Chinese and American AASHTO as well as ASTM standards.