No abstract

No abstract

In simple understanding a product manufactured with usual or special composition of aggregates, cementing material, water, with or without reinforcement at a place and used else-where to function, can be termed as precast product. Bricks of different kinds, cement-mesh works, lining works of open ground wells can be thought of primitive/initial precast products. A few decades back, India with its largest network of railway tracks, could replace different types of track-sleepers with PSC (prestressed concrete) sleepers. They are factory produced precast products which are pre-stressed by pre-tensioning. Accomplishing this gigantic task, at very early times in the advancement of precast-construction, India still needs to catch-up the wide applicability of the methodology. This is necessitated because the country's priorities are moving around mass housings, public toilets, community utilities like drainages, roadways, transporting of petroleum products and many more. Having talked to some extent about precast, now it is high time to define it. Precast concrete construction is defined as "a method of execution of a structure, wherein the structure as a whole or its component segments are cast beforehand, off-site, either at nearby available location or a separate and exclusive plant/factory, cured, transported and placed/connected on-site to function". Each process cited in the definition, is a characteristic feature and is again a field of study/practice.

No abstract

Robotics and automation are playing very imperative role in the modern construction practice to meet the challenges and expectation specifically in the infrastructural projects. Automation is a tool for operating or controlling different stages of construction process using mechanized and electronic devices or control systems to reduce the human intervention to a minimum. The design and implementation of these automation technologies has shown progressive outcomes compared to conventional methods. Moreover, considerable improvement in working condition, reduction in accidents and significant increase in production have been evidently observed in the recent construction projects as well as in the earlier research studies. Although several countries have adopted automation in their construction projects, application of these techniques in India is limited to a greater extent due to lack of proper guidelines and specifications. It is important to develop appropriate standards and guidelines for Indian construction sector. This paper reviews different automation techniques that are currently used in many parts of the world and suggestions for their application in the Indian construction scenario are discussed in detail. Moreover, guidelines for efficient design and implementation of automation techniques in India are highlighted in this paper.