Concrete

Currently, we are not using fly ash in the cement and concrete blend due to regulatory issues

Published

12 years ago

July 31, 2014

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Sudhir Hoshing, CEO-Roads, Reliance Infrastructure Though the regulatory systems are yet to evolve and embrace the new construction material, fly ash has already proved its worth in several large-scale construction projects all over the world. Fly ash has been used in tall building structures like the Petronas Towers in Malaysia. Eurotunnel, the second largest rail tunnel had fly ash mixed in the concrete. In India it has been used in Bhakhra Dam, Rihand Dam, Rajasthan Atomic Power Plant, private builders like Hiranandani Developers, DLF have been using fly ash in residential buildings. ICR interacts with Sudhir Hoshing, CEO-Roads, Reliance Infrastructure, to gauge how the trend is catching up in India.

What are the benefits of blending fly ash in cement?
Fly ash, being a by-product of coal combustion, offers environmental advantages by diverting the material from the waste stream, reducing the energy investment in processing virgin materials, conserving virgin materials, and by allaying pollution.

It also improves the performance and quality of concrete as it:

Affects the plastic properties of concrete by improving workability, reducing water demand, reducing segregation and bleeding, and by lowering heat of hydration.
Fly ash increases strength, reduces permeability, reduces corrosion of reinforcing steel, increases sulphate resistance, and reduces alkali-aggregate reaction.
Fly ash reaches its maximum strength more slowly than concrete made with only Portland cement.
Reduces requirement of cement for same strength of concrete thus making the mix economical.
No special technique is needed to use fly ash blended concrete. It is to be used as per standard established method.

Does blending vary, based on the type of fly ash or application?
Based on the type of coal used, two different types of fly ashes are produced. Anthracite and bituminous coal produces fly ash classified as Class F. Class C fly ash is produced by burning lignite or sub-bituminous coal. For sulfate environments, only Class F fly ash will be permitted and under no circumstances will Class C fly ash be used.

Class F fly ash will typically require an air entraining agent to be added. Class C fly ash will not.

How is the availability of good quality fly ash in the country?
In India fly ash is being used to produce fly ash based PPC. Because in India the power plants basically use lignite and sub-bituminous coal, the Class F fly ash is relatively easy to obtain.

Do you use fly ash in your cement/concrete blends? To what extent?
Currently, we are not using fly ash in cement/concrete blends due to regulatory issues. However, fly ash is permitted for use in embankments, earthwork, etc. Generally, 15 to 28 per cent fly ash is used in such applications.

No special technique is needed to use fly ash blended concrete.

Concrete

Ultra Concrete Age

Prof. A. S. Khanna (Retd., IIT Bombay) on how Ultra-high performance concrete (UHPC) improves strength, durability and lifecycle performance.

Published

1 week ago

April 1, 2026

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The need of present time is stronger buildings, industrial or common utility buildings, such as Malls, Railway stations, hospitals, offices, bridges etc. For this, there is need of long durable, tough and stable concrete, which could stand under normal and seismic conditions. Tough railway bridges are required for bullet trains to pass without any damage. Railway tunnels, sea-links, coastal roads, bridges and multistorey buildings, are the need of the hour. The question comes, is the normal cement called OPC is sufficient to take care of such requirements or better combination of cements and sand mixtures is required?

Introduction

A good stable building structure can be made with a good quality of cement+sand+water system. Its quality can be enhanced by keeping the density of admixture higher (varies from 30 in normal buildings to bridges etc to 80). Further enhancement in the properties of various cements admixtures is made by adding several additives which give additional strength, waterproofing, flexibility etc. These are called construction chemicals…

To read the full story Click Here

Concrete

NCB Signs MoU With Cement Manufacturer To Boost Construction Skills

Partnership to deliver nationwide training and certification

Published

1 week ago

March 31, 2026

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The National Council for Cement and Building Materials (NCB) has signed a memorandum of understanding with a leading cement manufacturer to strengthen skill development and capacity building in the construction sector. The agreement was formalised at NCB premises in Ballabgarh and was signed by the Director General of NCB, Dr L. P. Singh, and the head of technical services at UltraTech Cement Limited, Er Rahul Goel. The collaboration seeks to bring institutional resources and industry expertise into a structured national training effort.

The partnership will deliver structured training and certification programmes across the country aimed at enhancing the capabilities of civil engineers, ready?mix concrete (RMC) professionals, contractors, construction workers and masons. Programme curricula will cover material quality testing, concrete mix proportioning, durability assessment and sustainable construction practices to support improved construction outcomes. Emphasis is to be placed on standardised assessment and certification to raise practice levels across diverse construction roles.

Practical learning elements will include workshops, site demonstrations, technical seminars and exposure visits to plants and RMC facilities to strengthen applied skills and on?site decision making. The Director General indicated confidence that a large number of professionals and workers would be trained over the next three to five years under the initiative. The partnership is designed to complement flagship government schemes such as the Skill India Mission and to align training outputs with national infrastructure priorities.

By combining the council’s technical mandate with industry experience, the initiative aims to develop a more skilled and quality?conscious workforce capable of meeting rising demand in infrastructure and housing. NCB will continue to coordinate programme delivery and quality assurance while industry partners provide practical exposure and technical inputs. The collaboration is expected to support long?term capacity building and more sustainable construction practices nationwide.

Concrete

JSW Cement Commissions Nagaur Plant, Enters North India

New Rajasthan unit boosts capacity to 24.1 MTPA and expands reach

Published

2 weeks ago

March 30, 2026

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JSW Cement has strengthened its national presence by commencing production at its greenfield integrated cement plant in Nagaur, Rajasthan, marking its entry into the north Indian market.

With this commissioning, the company’s installed grinding capacity has increased to 24.1 MTPA, while total clinker capacity, including its joint venture operations, stands at 9.74 MTPA.

The Nagaur facility comprises a 3.30 MTPA clinkerisation unit and a 2.50 MTPA cement grinding unit, with an additional 1.00 MTPA grinding capacity currently under development. Strategically located, the plant is positioned to serve high-growth markets across Rajasthan, Haryana, Punjab and the NCR.

The project has been funded through a mix of equity and long-term debt, with Rs 800 crore allocated from IPO proceeds towards part-financing the unit.

Parth Jindal, Managing Director, JSW Cement, stated that the commissioning marks a key milestone in the company’s ambition to become a pan-India player. He added that the project was completed within 21 months and positions the company to achieve its targeted capacity of 41.85 MTPA by FY29.

Nilesh Narwekar, CEO, JSW Cement, highlighted that the expansion aligns with the company’s strategy to tap into rapidly growing northern markets driven by infrastructure development. He noted that the company remains focused on delivering high-quality, eco-friendly cement solutions while progressing towards its long-term capacity goal of 60 MTPA.

The Nagaur plant has been designed with sustainability features, including co-processing of alternative fuels and a 7 km overland belt conveyor for limestone transport to reduce road emissions. The facility will also incorporate a 16 MW Waste Heat Recovery System to improve energy efficiency and lower its carbon footprint.

JSW Cement, part of the JSW Group, operates across the building materials value chain and currently has eight plants across India, along with a clinker unit in the UAE through its joint venture.