What is cement? Cement is a binding element of silica hydrates in both mortar and concrete, it is made up of limestone, silica and sand. It sets and hardens when combined with water. Storage of cement Cement should be kept away from moisture and dampness since it’s extremely moisture sensitive, and exposure to water results with hardening and formation of clumps. Keep covered sheets or tarpaulin in a dry enclosed structure away from rain and moisture. Cement bags should not be placed directly on concrete or wooden floors but 150mm200 above. In the storage building there should be as few windows as possible. Stack bags close together to reduce air circulation. Cement of various types must be stacked and stored separately. Put labels of the date of the cement and stack in a way that would make it easy to use by first come, first use. Bulk cement It’s cement that is transported and delivered in large quantities. It’s benefits include :automatic cement unloading via the bulker truck’s blower. Unloading cement does not necessitate the use of labor, as it does with baggage cement. For Cement stored in silos, old stock is automatically used first. The packing cost is reduced and chances of cement Hydration are reduced. The system is clean. Hydration of Cement The chemical reaction that occurs when cement and water come into contact. Hydration is divided into five stages :Initial reaction, Dormancy, strength acceleration, speed reduction and steady development. White cement High alumina cement Despite its origins as a chemically resistant cement, high alumina cement (HAC) found early application due to its rapid strength development. Because of its high early strength, it was widely used in the 1960s in the production of precast prestressed beams or joists. Its use allowed the manufacturer to complete the mold in less than 24 hours. In 1973–74, three buildings that used such beams failed, and there was immediate concern about the many buildings that used these beams or joists.(BushnellWatson and Sharp, 1990) Calcium Aluminate Cement Cement Extenders A chemical additive or inert material added to a cement slurry to reduce density or increase yield. Slag Ground granulated blastfurnace slag (GGBS) GGBS is a byproduct of the iron-producing blast furnace process. Blast furnace slag is primarily composed of silica and alumina derived from iron ore, as well as lime or dolomitic limestone. As a fluxing agent, lime was added. It is cooled slowly so that it can be able to function as an extender. (Owens and Fulton, 2009) Fly ash Extracted from the flue gases of pulverized coal-fired furnaces using electrostatic precipitators or bag filters Fly Ash is separated into fine and coarse fractions after extraction. About 10% of the fine fraction is used as a cement extender. (Owens and Fulton, 2009) Reference 1.The Spruce. 2021. Cement, Concrete, and Mortar: Understanding the Differences. [online] Available at: https://www.thespruce.com/difference-between-cement-concreteand-mortar-2130884 [Accessed 24 October 2021]. 2.CivilBlog.Org. 2021. HOW TO STORE CEMENT ON SITE? – CivilBlog.Org. [online] Available at: https://civilblog.org/2014/11/13/how-to-store-cement-on-site/ [, B. and Transportation, B., 2021. Bulk Cement – Storage and Transportation. [online] Mastercivilengineer. Available at: https://mastercivilengineer.com/bulk-cement-storageand-transportation/ [Accessed 22 October 2021]. 4.The Screed Scientist®. 2021. Storage and Handling of Cement and Aggregates – The Screed Scientist®. [online] Available at: https://www.screedscientist.com/floor-screeding/storage-and-handling-ofcement-and-aggregates/ [Accessed 22 October 2021]. 5.Maturix. 2021. What is Cement Hydration? – Maturix Concrete Monitoring. [online] Available at: https://maturix.com/knowledge-center/what-is-cementhydration/#:~:text=When%20cement%2C%20water%2C%20aggregate%2C,and%20water%20(called%20 hydration). [Accessed 24 October 2021]. 7.Bushnell-Watson, S. and Sharp, J., 1990. On the cause of the anomalous setting behavior with respect to temperature of calcium aluminate cements. Cement and Concrete Research, 20(5), pp.677-686 8.Owens, G. and Fulton, F., 2009. Fulton’s concrete technology. 9th ed. Midrand: Cement & Concrete Institute, p.9.
