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Value added concrete

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After the ready-mixed concrete industry?s successful journey of 20 long years in India, the new era concrete has to perform many applications apart from achieving strength and workability. The article outlines some new developments in the field.

Water plus cement plus aggregates; the formula seems mighty simple, but in reality concrete manufacturing is a far more complex process. As India builds its infrastructure, the ready-mixed concrete industry is steadily gaining pace as the most viable option to speed up construction.

Various properties such as sustainability, easy flow, colourful, lightweight, high early strength, durability, etc., need to be attained to meet the requirements specified by the construction industry. A deft designing of concrete is done to achieve these properties. All such need-based concrete products are often tailor-made and as always, have proved to be value for money.

High volume Fly Ash/High Volume GGBS concrete
Supplementary Cemetitious Materials (SCMs) such as fly ash, GGBS (Ground Granulated Blast Furnace Slag) in concrete are in use for a reasonably long period due to the overall economy in their production as well as their improved performance characteristics in aggressive environments. High Volume GGBS and HVFA concrete is a major breakthrough as compared to conventional concrete due to cement savings, cost savings, environmental and social benefits offered by it. So it?s wide spread usage should be encouraged in extending the lifespan of structures.

Usage of High Volume GGBS and HVFA significantly reduces the risk of damages caused by Alkali-Silica Reaction (ASR), provides higher resistance to chloride ingress by making the concrete more impermeable and reduces the risk of reinforcement corrosion and also provides higher resistance to sulphate attacks and other chemicals. The resulting product has a much lower level of embodied CO2 than if OPC or ordinary cement replacements were used. With the increase of specific surface area and content of GGBS/HVFA, the repulsion between cement particles increases, improving the workability of the HVGGBS and HVFA incorporated concretes. To obtain maximum benefits, the optimum substitute content of HVFA is 50 per cent in standard and high grades; similarly optimum substitute content of GGBS is 70 per cent in standard and high grades of concrete.

Temperature controlled concrete
Cracking in mass concrete structures is undesirable as it affects the water-tightness, durability, appearance, and overall integrity of the structures. Cracking in mass concrete will normally occur when tensile stresses that surpass the tolerance limit of concrete are developed. These tensile stresses may occur due to imposed loads on the structure, but they more often occur because of the restraint against volumetric change. Largest volumetric change in concrete mass arises from change in temperature. The hydration of a concrete mixture is a process that liberates heat and the rate of heat generation is accelerated with the rise in concrete temperature. Concrete is a poor conductor of heat, and the rate of heat evolution due to the hydration process is much greater than the rate of heat dissipation. Development of high concrete temperatures can cause a number of effects that are detrimental to the long-term concrete performance such as:

  • Thermal stresses and thermal cracking
  • The tendency for drying shrinkage cracking
  • Decreased long-term concrete strengths and durability as a result of cracking
  • Loss of structural integrity and monolithic action, and
  • Permeability.

Steel fibre reinforced concrete
Concrete is strong in compression but weak in tension and hence, in structural applications this shortcoming of concrete is overcome by providing steel reinforcing bars to bear the tensile forces once the concrete has cracked. In reinforced concrete, the tensile failure strain of the concrete is significantly lower than the yield strain of the steel reinforcement and the concrete cracks before any significant load is transferred to the steel(1). Short, discrete steel fibres provide discontinuous three-dimensional reinforcement that pick up load and transfer stresses at micro-crack level. This reinforcement provides tensile capability and crack control to the concrete section before the establishment of visible macro cracks, thereby endorsing ductility or toughness.

Steel fibres modify concrete properties as follows:

  • Improve mix rheology or cracking characteristics in the plastic stage
  • Improve the tensile or flexural strength
  • Improve the impact and abrasion resistance
  • Control cracking and the mode of failure by means of post-cracking ductility, and
  • Improve durability.

The functions of steel fibres and conventional concrete reinforcement are clearly different. Steel fibres are added to concrete mainly to influence the way in which concrete cracks as it fails. Micro-cracks form when concrete is loaded. Fibres bridge cracks during loading and hence, influence mechanical performance.

Steel fibres have a tensile strength typically 2-3 times greater than traditional fabric reinforcement and a significantly greater surface area (for a given mass of steel) to develop bond with the concrete matrix(2). The average fibre pull-out length is l/4, which for the longest 60mm fibres, is only 15mm. This length is insufficient to allow efficient use to be made of the high tensile strength of drawn wire unless devices such as bends, crimps or flattened ends are used to improve anchorage efficiency(3).

Factors that influence performance of steel fibres in concrete are:

  • Bond and anchorage mechanisms (e.g., straight or deformed shape, end conditions, cones or hooked ends)
  • Aspect ratio (the fibre length and diameter)
  • Dosage (kg/m3)
  • Fibre count (number of fibres per kg of fibres), which is a function of fibre size and dosage
  • Tensile strength, and
  • Elastic modulus

Depending on the service life and exposure conditions, steel fibres by virtue of their disconnected nature and small diameter eliminate corrosion and associated spalling damage compared to steel rebar and enhance resistance to chloride and carbonation induced corrosion. Unlike synthetic macrofibres, they are not affected by elevated temperatures.

Reference
1.Technical Report No. 63, Guidance for the Design of Steel-Fibre-Reinforced Concrete, 2007, p 1
2.Technical Report No. 63, Guidance for the Design of Steel-Fibre-Reinforced Concrete, 2007, p 4
3. John Newman and Ban Seng Choo Advanced Concrete Technology, Processes, 2003, p 6/9

Technologies from RMC Readymix (India)
Environprotectcrete

In an era of growing environmental consciousness, more and more customers are adopting Green Building Certifications such as LEED? India developed by Indian Green Building Council (IGBC) or Green Rating for Integrated Habitat Assessment (GRIHA) developed by The Energy Resource Institute (TERI). Environprotectcrete? provides desired levels of consistence and the compressive strengths at various ages, depending upon client requirements and enables the customers to earn more points, thus facilitating the process of obtaining certification and enhancing the ratings.

Thermocrete
It is chilled concrete that gives control over the temperature differential between the core and surface of the concrete, thereby mitigating thermal tensile cracks. It also prevents delayed ettringite formation, which may occur in certain concretes of particular chemical makeup exposed to temperatures over about 70?C during curing stage.

FRCcrete
This product incorporates steel fibres, based upon expected loading and sub-base conditions, and completely does away with reinforcement bars in ground supported slabs.

RMC Readymix (India)
The company is a division of Prism Cement Limited, and is one of the largest ready-mixed concrete manufacturers in India. Established in 1996, the company operates 90 ready-mixed concrete plants in 37 cities and towns across the country. The company has always been one of the leaders in setting standards for plant and machinery, production, quality systems and product services in the ready-mixed concrete industry.

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Concrete

India Sets Up First Carbon Capture Testbeds for Cement Industry

Five CCU testbeds launched to decarbonise cement production

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The Department of Science and Technology (DST) recently unveiled a pioneering national initiative: five Carbon Capture and Utilisation (CCU) testbeds in the cement sector, forming a first-of-its-kind research and innovation cluster to combat industrial carbon emissions.
This is a significant step towards India’s Climate Action for fostering National Determined Contributions (NDCs) targets and to achieve net zero decarbonisation pathways for Industry Transition., towards the Government’s goal to achieve a carbon-neutral economy by 2070.
Carbon Capture Utilisation (CCU) holds significant importance in hard-to-abate sectors like Cement, Steel, Power, Oil &Natural Gas, Chemicals & Fertilizers in reducing emissions by capturing carbon dioxide from industrial processes and converting it to value add products such as synthetic fuels, Urea, Soda, Ash, chemicals, food grade CO2 or concrete aggregates. CCU provides a feasible pathway for these tough to decarbonise industries to lower their carbon footprint and move towards achieving Net Zero Goals while continuing their operations efficiently. DST has taken major strides in fostering R&D in the CCUS domain.
Concrete is vital for India’s economy and the Cement industry being one of the main hard-to-abate sectors, is committed to align with the national decarbonisation commitments. New technologies to decarbonise emission intensity of the cement sector would play a key role in achieving of national net zero targets.
Recognizing the critical need for decarbonising the Cement sector, the Energy and Sustainable Technology (CEST) Division of Department launched a unique call for mobilising Academia-Industry Consortia proposals for deployment of Carbon Capture Utilisation (CCU) in Cement Sector. This Special call envisaged to develop and deploy innovative CCU Test bed in Cement Sector with thrust on Developing CO2 capture + CO2 Utilisation integrated unit in an Industrial set up through an innovative Public Private Partnership (PPP) funding model.
As a unique initiative and one of its first kind in India, DST has approved setting up of five CCU testbeds for translational R&D, to be set up in Academia-Industry collaboration under this significant initiative of DST in PPP mode, engaging with premier research laboratories as knowledge partners and top Cement companies as the industry partner.
On the occasion of National Technology Day celebrations, on May 11, 2025 the 5 CCU Cement Test beds were announced and grants had been handed over to the Test bed teams by the Chief Guest, Union Minister of State (Independent Charge) for Science and Technology; Earth Sciences and Minister of State for PMO, Department of Atomic Energy, Department of Space, Personnel, Public Grievances and Pensions, Dr Jitendra Singh in the presence of Secretary DST Prof. Abhay Karandikar.
The five testbeds are not just academic experiments — they are collaborative industrial pilot projects bringing together India’s top research institutions and leading cement manufacturers under a unique Public-Private Partnership (PPP) model. Each testbed addresses a different facet of CCU, from cutting-edge catalysis to vacuum-based gas separation.
The outcomes of this innovative initiative will not only showcase the pathways of decarbonisation towards Net zero goals through CCU route in cement sector, but should also be a critical confidence building measure for potential stakeholders to uptake the deployed CCU technology for further scale up and commercialisation.
It is envisioned that through continuous research and innovation under these test beds in developing innovative catalysts, materials, electrolyser technology, reactors, and electronics, the cost of Green Cement via the deployed CCU technology in Cement Sector may considerably be made more sustainable.
Secretary DBT Dr Rajesh Gokhale, Dr Ajai Choudhary, Co-Founder HCL, Dr. Rajesh Pathak, Secretary, TDB, Dr Anita Gupta Head CEST, DST and Dr Neelima Alam, Associate Head, DST were also present at the programme organized at Dr Ambedkar International Centre, New Delhi.

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Concrete

JK Lakshmi Adopts EVs to Cut Emissions in Logistics

Electric vehicles deployed between JK Puram and Kalol units

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JK Lakshmi Cement, a key player in the Indian cement industry, has announced the deployment of electric vehicles (EVs) in its logistics operations. This move, made in partnership with SwitchLabs Automobiles, will see EVs transporting goods between the JK Puram Plant in Sirohi, Rajasthan, and the Kalol Grinding Unit in Gujarat.
The announcement follows a successful pilot project that showcased measurable reductions in carbon emissions while maintaining efficiency. Building on this, the company is scaling up EV integration to enhance sustainability across its supply chain.
“Sustainability is integral to our vision at JK Lakshmi Cement. Our collaboration with SwitchLabs Automobiles reflects our continued focus on driving innovation in our logistics operations while taking responsibility for our environmental footprint. This initiative positions us as a leader in transforming the cement sector’s logistics landscape,” said Arun Shukla, President & Director, JK Lakshmi Cement.
This deployment marks a significant step in aligning with India’s push for greener transport infrastructure. By embracing clean mobility, JK Lakshmi Cement is setting an example for the industry, demonstrating that environmental responsibility can go hand in hand with operational efficiency.
The company continues to embed sustainability into its operations as part of a broader goal to reduce its carbon footprint. This initiative adds to its vision of building a more sustainable and eco-friendly future.
JK Lakshmi Cement, part of the 135-year-old JK Organisation, began operations in 1982 and has grown to become a recognised name in Indian cement. With a presence across Northern, Western, and Eastern India, the company has a cement capacity of 16.5 MTPA, with a target to reach 30 MT by 2030. Its product range includes ready-mix concrete, gypsum plaster, wall putty, and autoclaved aerated fly ash blocks.

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Concrete

Holcim UK drives sustainable construction

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Holcim UK has released a report titled ‘Making Sustainable Construction a Reality,’ outlining its five-fold commitment to a greener future. The company aims to focus on decarbonisation, circular economy principles, smarter building methods, community engagement, and integrating nature. Based on a survey of 2,000 people, only 41 per cent felt urban spaces in the UK are sustainably built. A significant majority (82 per cent) advocated for more green spaces, 69 per cent called for government leadership in sustainability, and 54 per cent saw businesses as key players. Additionally, 80 per cent of respondents stressed the need for greater transparency from companies regarding their environmental practices.

Image source:holcim

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