The manufacture of Portland cement was started in England around 1825. Belgium and Germany started the same in 1855. America started the same in 1872 and India started the same in 1904. The first cement factory was installed in Tamil Nadu in 1904 by South India Industry Limited and then onwards a number of factories manufacturing cement were started. Our [...]
In this article we will discuss about:- 1. Characteristics of Cement 2. Properties of Cement 3. Composition 4. Functions of Ingredients 5. Harmful Constituents 6. Setting Action 7. Site for Factory 8. Packing 9. Ball Mills and Tube Mills 10. Field Tests 11. Storage 12. Uses. Characteristics of Cement: Following are the characteristics of cement: (i) The colour of cement [...]
The entire manufacturing process in a modern plant is now controlled through a microprocessor based programmable logic control system to maintain a consistently uniform quality of cement and a high rate of production. The entire operation of the plant is controlled centrally in a single control room and the plant employs minimum of manpower as compared to previous plants constructed [...]
The following types of cement are used in Construction. 1. Acid-Resistant Cement: Acid-resistant cement is composed of the following: (i) Acid-resistant aggregates such as quartz, quartzites, etc. (ii) Additive such as sodium fluosilicate Na2 SiF6; and (iii) Aqueous solution of sodium silicate or soluble glass. The addition of additive sodium fluosilicate accelerates the hardening process of soluble glass and it [...]
The exhaustive tests are carried out in laboratory to decide precisely the quality of cement. The extreme care should be taken to collect the sample of cement from site. In order to make a representative sample, it is desirable to collect in nearly equal portions as follows: (1) When Cement is Loose: It should be taken from at least 12 [...]
Following four materials are required for making R.C.C.: 1. Cement 2. Aggregates 3. Steel 4. Water. 1. Cement: Before the introduction of ordinary Portland cement, the lime was used as a cementing material. Most of the cement concrete work in building construction is done with ordinary Portland cement at present. But other special varieties of cement such as rapid hardening [...]
Following tests are carried out in laboratory on the samples of aggregates to ascertain their some of the properties: The quality of aggregates plays a great role in the performance and long-term economy of the structure. The aggregates also bear the main stresses occurring in the R.C.C items like slab, beam, columns, etc. and resists wear from surface abrasion. The [...]
In this article we will discuss about:- 1. Advantages of Portland Pozzolana Cement (PPC) 2. Disadvantages of Portland Pozzolana Cement (PPC) 3. Use. Advantages of Portland Pozzolana Cement (PPC): If the right quality fly ash is used in optimum percentage, the following advantages of Portland pozzolana cement (PPC) have been observed over ordinary Portland cement. They are: 1. It is [...]
Cement paste consists of hydrates of various cement compounds as C3S, C2S, C3A, C4AF and Ca (OH)2 and the gross volume available for these products of hydration is the sum of absolute volume of dry cement and the volume of the mix water. Thus the cement paste consists of gel of hydrates of cement compounds, Ca(OH)2 and gel pores either [...]
Portland cement can be manufactured by intimately mixing together calcareous and argillaceous stones containing silica, alumina, and iron oxide etc. and burning it in large rotary kilns at a temperature of approximately 1400°C to 1500°C. At his temperature the materials partially fuse, forming clinker. This clinker is cooled and ground to fine power. Usually it is gray or brownish in [...]