Utilization of Unused Old Cement in Construction Materials

India is the second biggest producer and consumer of cement with the generation of 380–390 million tons in the FY 2023, it is expected to add 80 million tons of cement by the year 2024 due to expected demand in housing and infrastructure development. According to IBEF past five years data, it was estimated, approximately every year 2–3 million tons of cement produced is unused. The production of cement is highly carbon intensive, if such a huge amount of cement remains unused and disposed unscientifically may lead to environmental issues such as hindrance to ground water recharge, nondegradable landfills, obstructing surface run-off, etc. Several construction materials, viz, pavers, low strength and nonstructural concrete, nonload bearing masonry, etc., need not need more strength for construction. Thus, an attempt is made to utilize and evaluate the effect of unused old cement in construction materials like paver blocks and mud concrete blocks. Cement samples were characterized for its basic physical properties and the developed construction materials were subjected to microstructure analysis viz scanning electron microscopy technique. The compressive strength of developed Box-shaped paver blocks was evaluated. Initial rate of absorption, water absorption, density of blocks and strength parameters were assessed for mud concrete blocks. Results indicated a reduction in strength of concrete by more than 30% and 50% for 1-year and 2-year-old cement, respectively. Also, loss of ignition value was observed in cement due to ageing. Application of paver blocks was found to be feasible in light and nontraffic roads.