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 [...]
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 [...]
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 [...]
The manufacture of cement requires strict control on its quality. Therefore the following tests and specifications have been laid as per I.S.I. 269-1967 and 1976: 1. Chemical composition 2. Fineness 3. Soundness 4. Consistency test 5. Setting time 6. Compressive strength 7. Tensile strength 8. Heat of Hydration. 1. Chemical Composition: The ordinary and rapid hardening Portland cements can be [...]
The below mentioned article will guide you about how to determine the fineness of cement. Determination of Fineness of Cement by Specific Surface by Blaine Air Permeability Method (as per IS 4031-1958): The determination of specific surface of cement is a recent development. It is a very accurate method of determining the firmness of cement, which affects the hydration and [...]
Cement concrete is an important construction material. Its importance is increasing every day. It is a composite material consisting of a binding material, which is essentially cement, inert mineral Filler, known as aggregates and water. Thus cement concrete can be prepared by mixing above ingredients in a fixed proportion. Green concrete is a plastic mass, which can be moulded into [...]
In this article we will discuss about:- 1. Introduction to High Alumina Cement 2. Manufacture of High Alumina Cement 3. Hydration 4. Effect of Conversion 5. Effect of Curing Temperature 6. Physical Properties 7. Refractory Properties. Introduction to High Alumina Cement: This cement is quite different from ordinary Portland cement in its composition and also in some properties. Hence its [...]