In the area of bridge and tunnel construction, there are numerous examples of precast concrete construction in india. Some of the reasons for such extensive usage are obviating the difficulties of working in water and in urban areas with traffic congestion speed of construction better quality of construction, etc. For bridge/tunnel sectors the precasting is mostly done in a creative manner for each site with specific products. This is mainly because the design scheme and construction method are often tightly interlinked. In USA, AASHTO has developed standard beam design for various load and geometrical condition and standard concrete beams are available for various spans and load conditions for ready usage. Unfortunately, this is not the situation India because there are no standard size available in India codes – even for road over bridges crossing railway where a good amount of standardization can be done. It is highly recommended that Indian infrastructure sector moves towards using standard designs and then precast manufacturers can make them available as and when needed avoiding delay in road/bridge constructions.
In the field of buildings, Precast concrete element were more popular for long span roofs or for roofs at a large height, where erecting scaffolding would have posed difficulties. Precasting of repetitive architectural elements was also popular, where this section were involved and surface finish and aesthetics were important. Many industrial structures with complex forms designed or constructed by expert consultants or architects were also good opportunities for using precast construction. Recently, for tall structure some of the larger construction agencies have started using custom-precast elements for faster and economical construction. The ITPL building in Bangalore, where precast hollow core blocks were used on a large scale was one of the pioneering applications in this country. many industries prefabricated building system (or, modular system) has been tried out in India apart from traditional precast construction with panel system or framed system, such as GFRG, panel building system with sandwich panels, 3-S system, Expanded polystyrene system, Pre-Engineering building system,etc.Some of these systems, as for instance the GFRG system, have been designed and also tested for resisting seimic condition even for multi-storey construction, whereby the technical efficiency has been well established. Apparently, there is no macro level consensus yet on “the appropriate method” for Indian low cast, mass construction schemes. With collaborations from some international precast element manufacturing agencies, a few plants have been set up to manufacture standard precast concrete elements, particularly hollow core slabs. Today, that there are about 50 precast plants in the country, many of them for captives use only. However, most of these have not been able to thrive as expected so far due to a variety of reasons. Fortunately, the acceptance of precast concrete elements has been showing an increasing trend in recent times in both public and private sector. However, to meet the goal of the “Housing For All” scheme, it is necessary to significantly increase the acceptance and usage of precast concrete technology wherever possible. The Government can play a significant role in many ways.
Regarding the governing standards and specifications, the National Building Code (NBC) has a section on prefabrication and there are some thirty-add BIS standards on precast elements.The Indian Concrete Institute (ICI) is just releasing a Handbook on Precast Concrete Construction, as a result of a major initiative started by the Late Dr A. Ramakrishna, a Doyen of precast construction. However, overaching, comprehensive documents such as the PCI Handbook of USA, fib Bullettin 74, or a major standardization document such as Beton Kalender of Germany are not yet developed by Indian agencies to guide the precasting industry as well as users.