Engineering Term of the Month CEMENT
Cement is a binding material , often mixed with other materials such as sand , aggregates , and water to create concrete or mortar . Portland cement is a commonly used type of cement . Portland cement is manufactured from raw materials such as limestone , clay , sand , fly ash and mill scale , which are blended and heated to very high temperatures to create a chemical reaction .
There are six basic types of Portland cement , identified as Type I , II , II ( MH ), III , IV and V . Type I is a general-purpose cement . Type II and II ( MH ) are for conditions where sulfate resistance is required , such as for concrete exposed to seawater . Type III is for high early strength . Type IV is used where minimizing the heat of hydration is necessary where thermal cracking is likely , such as massive structures like dams . Type V is used where resistance against severe sulfate attack is required .
Cement is used in many , if not most , civil engineering structures . Key examples include bridges , dams , buildings , roadways , tunnels , and utility pipes .
Sources :
• www . britannica . com
• ACI Education Bulletin E3-13 , Cementitious Materials for Concrete , 2013
• www . civilengineeringforum . me / concrete-mix-design-by-aci /