Cement testing as per Indian standards IS: 4031, i.e., primarily determination of Normal Consistency of cements and subsequently gauging of cement mortar is  carried out manually and requires skill and experience for better accuracy, precision and reproducibility. In the changing times with less skilled manpower the manual methods result in issues of reliability and reproducibility  At the authors’ lab, substantial test data were generated, so as to have comparison of cement mortar tests’ results for OPC, PPC & PSC gauged with manual and mechanical mixing (using Hobart mixer) &am ..read more

In a concrete environment the steel reinforcement is chemically passivated by the alkalinity of the concrete cover, the rate of corrosion under ideal conditions is negligible, however due to the  changes in the conditions around the steel reinforcement, the rates of corrosion can reach alarming proportions .  Steel reinforcements is often used in severe environments where soluble chlorides are present . Ingress  of chloride in the concrete surrounding the reinforcements ( coastal environment or in regions where deicing salts are used ) disrupts the passive protective oxide layer ..read more

The availability of limestone deposits containing lower MgO content (< 2 %) is slowly depleting and many cement plants are forced to accept limestone having higher MgO (> 3.0 %) for cement manufacture. Unsoundness problems in cement associated with high MgO content (Periclase formation) are well known and there is a need to study and understand the undesirable effects of high MgO content on the clinker quality. Extensive studies of raw mix design and optimisation have been carried out at author’s laboratory with raw materials from different plants with higher MgO contents. These studies ..read more

A presentation was made at the Webinar   : Sustainable Cement of the Future: With Fly Ash and Bauxite Residue, Organised By : Ms  Vedanta Ltd ,16th July 2021, om the Use of Red Mud (Bauxite residues ) for improved quality of Porland clinker /for increased Fly ash in PPC along with conservation of Natural Materials. The ppt discusses various properties of Red Mud and discusses the advantages of its use as corrective material especially with use of suulphur rics coals and petcoke . It also includes other reported applications of Red Mud being studied by different researchers and m ..read more

Abstract: There is an increasing realisation in the building industry that we can no longer ignore the issues of environmental degradation and its effects on the delicate Eco-balance of our plant. It is well known that approximately 1.5 tons of limestone is consumed for every ton of cement.  As the manufacture of cement requires high temperature pyro-processing at       ~ 1450ºC, large amounts of fossil fuels and electrical energy are used.  Each ton of cement that is produced is accompanied by approx. 1 ton of carbon dioxide, which is one of the gases p ..read more

SUMMARY                              In the tropical climatic conditions that prevail in the Indian subcontinent, blended cements are reported to be an appropriate option for durable structures. The market acceptability of these cements is also on the increase.                             The USP’s of the blended cements ar ..read more

Abstract: The Author has had extensive experience in the field of quality upgradation and productivity enhancement of cement plants and have carried out number of assignments for its own cement plants and for its clients in India and abroad. The raw material based diagnostics approach practiced at the authors laboratory helps in identifying deficiency areas for the plant under study. The laboratory simulations studies help in optimising raw mix / clinker parameters, correctives / mineralisers to over come the quality problems and to achieve enhanced productivity of the plant. The authors have ..read more

It is known in the literature that Calcium Carbonate content has influence on the mechanical & thermal properties of PP / HDPE bags, used for packing cement at our works. It is observed that the tensile strength, elongation of HDPE bags, printability of the bags and other properties depends on the additions of CaCO3. In order to analyze and monitor the CaCO3 contents of the Bags used at Works from different suppliers, a procedure developed in labs for analysis of Calcium carbonate content in the PP / HDPE bags which can be carried out at works is detailed enclosed file . Chemical-procedure ..read more

The SO3 determined in the cement is the sum of SO3 of the different constituents: • Clinker • Mineral components (Fly ash ,Slag etc) • Calcium sulfate added for finish grinding . The SO3 from the different constituents does not react in the same manner. This reaction can considerably influence the cement properties in terms of the following : • Setting Time (Initial & Final ) • Rheology of the cement paste • Kinetics of hardening • Dimensional variations • Admixture Compatibility in the fresh concrete In case of clinker the SO3 is integrated in the crystal lattice. The contribution of sulf ..read more

Usage of  Fly ash based cement and concrete has become increasingly popular with the recognition that in addition to strength, other properties such as impermeability ,elastic modulus and resistance to corrosion are critical parameters for long term durability and low life cycle cost. The abundant availability of fly ash as a byproduct from coal fired thermal power plants has led researchers to focus on the factors responsible for the pozzolanacity of the fly ash as also the means for enhancing its reactivity . The comparative reactivity of Class-C and    Class – F fly ashe ..read more