In a candid chat with Indian Cement Review, J.K.Dasgupta, CEO & MD, JPM Engineers Pvt Ltd speaks about the tremendous progress achieved by structural engineering over the years with prevalence in the use of RMC over site mix concrete and emergence of admixtures in concrete setting.Please comment on the evolution in utilization of concrete over the yearsWhile working on projects today, nobody uses site mix concrete. Everyone has gradually shifted to the utilization of Ready Mix Concrete (RMC) over the years. Previously, when site mix concrete was used, there used to be a lot of wastage. Greater vigilance was required in order to ensure that the quality of the material was maintained and wastage was kept under control.Please comment on length on the advantages of using RMC over site Mix Concrete.There is no requirement of storage for basic materials at site. The wastage of materials is avoided to the barest minimum. There is a more streamlined organisation of the production process. There is no need for procurement or hiring of plant and machinery. There is an elimination of labour associated with the production of concrete. Pollution issues are effectively addressed with a reduction in noise and dust. Time required for production is also greatly reduced, leading to economization of operations.What is the role of chemical admixtures in concrete setting?Admixtures are primarily used by producers for modifying the properties of hardened concrete and ensuring that concrete quality is maintained during mixing, transportation, placing and curing. They are added to the mix immediately before or during mixing, either at the plant or onsite. The effective use of admixtures is largely determined by the use of suitable methods of batching and concreting. While most admixtures are used in a ready to use liquid form, certain admixtures like pigments, expansive agents and pumping aids are utilized in very small quantities and batched by hands from premeasured containers.What are the different kinds of admixtures?The classification of admixtures can be done on the basis of functions they perform. The five distinct classes of admixtures comprise of air-entraining, water-reducing, retarding, accelerating, and plasticizers (superplasticizers). There are other varieties of admixtures which broadly fall into the specialty category and are utilized for corrosion inhibition, shrinkage reduction, alkali-silica reactivity reduction, workability enhancement, bonding, damp proofing, and coloring. Air-entraining admixtures are used specifically for placing microscopic air bubbles into the concrete.Please elaborate on the kinds of software used in this fieldNowadays for structural design, 3-D analysis by taking all actual dimensions of the structure into consideration - is widely used for determining accurate forces on the structure, thus ensuring the strength and durability of a structure. Analysis is carried in a simulated manner wherein the earthquake analysis, wind analysis and the effect of other natural and artificial factors on the structure is carried out which is modeled on 3-D effect. The utilization of 3-D analysis has resulted in material cost savings (particularly reinforcement steel) on a structure to the tune of 10-15 percent, depending upon loading and complexity of the structure. Our company has invested an amount to the tune of Rs. 20 lakh (approx) over the years, to have all required latest state-of-the-art softwares, and keep ourselves updated.Please comment on the use of fly ash in RMCFly ash is used in RMC in order to infuse a comprehensive strength. It is used to increase pumpability of the concrete mix, reduce the quantity of fine sand in the mix. Fly ash also has certain inherent cementing properties. However, poor quality fly ash can have negative effect on the concrete. Using fly ash requires adequate knowledge of its use.What are the different kind of tests undertaken in order to test the strength and durability of the concrete?Several tests like cube test and slump test are undertaken during concreting in order to ensure the strength and durability of the concrete being used in the project. Destructive tests usually takes 28 days to ascertain strength of the concrete. Tests known as non destructive test are also undertaken to ascertain concrete strength at a later stage – if required.