Speaking of the manufacture of concrete, we shall look into the raw materials that form concrete first. The basic materials of concrete are cement, fine aggregate, coarse aggregate and water. In fact, a wide range of materials are used to manufacture concrete as the types and proportions of constituent materials are varied in order to achieve the strength and flexibility required in a particular setting. Structural concrete used in building construction normally consists of one part cement to two parts fine mineral aggregate to four parts coarse mineral aggregate (1 cement: 2 sand: 4 gravels).
Components of concrete: water, cement, fine mineral aggregate, coarse mineral aggregate
The process to manufacture concrete is fairly simple. Firstly, all ingredients—cement (usually Portland cement), aggregates (such as sand or gravel), admixtures (chemical additives), any necessary fibers, and water—are to be prepared. As thorough mixing produce uniform, high quality concrete, equipment and methods used should be capable of effectively mixing concrete materials. The mixing of cement and water into a paste goes first before combining these materials with aggregates. The next step is mixing the paste with aggregates so that the paste will bind the aggregates into a rocklike mass as the paste hardens due to the chemical reaction of the cement and water. Within this process lies the key to a remarkable trait of concrete: it's plastic and malleable when newly mixed, strong and durable when hardened.
The procedure of making concrete is important as it determines the quality as well as the properties of concrete made. The properties of concrete are categorized into fresh concrete properties and harden concrete properties. The properties of fresh concrete are as below:
1. Setting
2. Workability
3. Bleeding and Segregation
a. Bleeding
b. Segregation
4. Hydration
5. Air Entrainment
Following are the properties of hardened concrete:
1. Strength of concrete
2. Concrete Creep
3. Shrinkage
4. Modulus Of Elasticity
5. Water tightness (impermeability)
6. Rate of Strength gain of Concrete
The above properties of concrete shall be further discussed afterwards. Now, please use your two minutes to watch the video below. The clear and brief demonstration of making concrete in the video will give you an better idea on this topic. Enjoy! =)
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