Concrete

Durable concrete for tunnelling application

Published

14 years ago

July 31, 2012

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In this first part of the two-part series, EugenKleen of Mc-Bauchemie Mueller GmbH and Co.KG spells out the properties required in concrete and the types of concrete used in tunnelling application.Over the decade the use of concrete admixtures, especially plasticizers and superplasticizers, is showing upward trend in India. The advent of concrete pumps and transit mixers has also contributed to this, as the use of superplasticizers enables trouble-free pumping operations and minimizes pipe blockages. With the advent of major metro projects across India, durability of concrete used especially for tunnelling segments is of prime importance. The earlier attitude of taking recourse to the use of admixtures only after facing problems is changing fast, and now, in most tunnelling projects, high performing admixtures are already included in the specifications and the mix is designed to achieve the necessary properties.The concrete for tunnel segments necessitates the concrete to have the following properties:??Compressive strength??Workability??Surface finish??DurabilityAs part of the durability requirements, concrete is or should be generally tested for the following properties:??Chloride migration??Sulfate resistance??Water absorption??Acid resistance??Porosity??Freeze thaw resistanceThis can be achieved using the latest technologies available for concrete. Concrete is now no longer a material consisting of cement, aggregates, water and admixtures but it is an engineered material with several new constituents like PFA, GGBSF, Microsilica, Metakaolin, Colloidal Sillica and several other binders, fillers and pozzolanic materials. The concrete today can take care of any specific requirements under most exposure conditions.The mix designs are getting relatively complex on account of interaction of several materials and mix design calls for expertise in concrete technology and materials. High performance concretes will have to be adapted for tunnelling segments, considering special properties as well as low cost maintenance strategies.What type of concrete do we use?Concrete used in tunnelling applications need the following outstanding properties viz. Compressive strength, high workability, enhanced resistances to chemical or mechanical stresses, lower permeability, durability etc. this will necessitate the use of high performance concrete. Some HPC types which will hold the key for tunnelling applications can be classified into:??Self compacting concrete / high workability concrete??Concretes resistant against aggressive mediaSelf-Compacting Concrete (SCC)Self-Compacting or Consolidating Concrete (SCC), as the name signifies should be able to compact itself by its self-weight under gravity without any additional vibrations or compaction. Self compacting concrete should be able to assume any complicated formwork shapes without cavities and entrapment of air. The reinforcement should be effectively covered and the aggregated should be fully soaked in the concrete matrix. In addition, the concrete should be self-levelling type and self-defoaming without any external compaction.The formulation of self compacting concrete has the latest concrete technology and it requires in-depth knowledge of materials and meticulous testing procedures before the concrete is designated as SCC. Self compacting concrete has the following special advantages.??Saving of cost on machinery, energy and personnel for vibrating the concrete??Considerable improvements to exposed surfaces (Fair Faced Concrete), less efflorescence??Marked improvements in durability on account of better compaction??Extremely suitable for slim and complicated moulds??Covers reinforcement effectively??Better adhesive between cement binder and aggregates??Reduction in de-moulding time??Advantage with respect to sound pollutionTherefore while calculating the costing and economics of self compacting concrete all the above mentioned advantages should be converted to cost parameters. This kind of concrete can give advantage of good compressive strength, workability and finish to the tunnel segments and may prove suitable.Durable concrete resistant against aggressive mediaOne major application of HPC is to increase the durability of concrete where aggressive underground conditions are anticipated. This can be achieved physically by resorting to very dense aggregate packing.Practically possible by selecting a very smooth sieve line from largest aggregate to the smallest grain of mineral additives like microsilica or new generation aluminosilicate slurries. Chemically, cement by itself is not acid resistant. The acid resistant binder is formed by combination of cement, microsilica / aluminosilicate and flyash. To control permeability very low water cement ratio has to be adopted. So as to provide the essential concrete properties a high-performance PCE (polycarboxylate ether) needs to be incorporated in the mix. By adjusting the particle size distribution on the micro scale the permeability of the concrete is reduced which minimizes the penetration of aggressive substances. Depending on the degree of dispersion these material particles more or less completely fill the spaces between the cement particles. During hydration the pozzolanic silica reacts with the free calcium hydroxide to form calcium silicate hydrates. This gives a denser concrete structure.(Source: Paper presented by the author at the Construction Chemicals International Conference 2012 held in Mumbai)

Concrete

Cement Makers Reaffirm Commitment to Sustainable Growth

Published

6 days ago

June 5, 2026

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World Environment Day spotlight on innovation and circularity

On World Environment Day, the Indian cement industry reiterated its commitment to supporting India’s climate ambitions through sustainable manufacturing, resource efficiency and the adoption of cleaner technologies.

The Cement Manufacturers’ Association (CMA) said the sector remains aligned with the Government of India’s Net Zero commitments and is accelerating efforts to reduce its environmental footprint while supporting the country’s infrastructure and development agenda.

Parth Jindal, President, CMA and Managing Director, JSW Cement, said the industry is increasingly adopting cleaner technologies, improving energy efficiency and expanding the use of alternative fuels and raw materials. He also highlighted the growing importance of circular economy practices, where industrial by-products and waste streams from one sector are utilised as resources in another.

“The Indian Cement Industry is aligned to the Government’s commitments on carbon mitigation and is accelerating the adoption of cleaner technologies, resource efficiency and circular economy practices while actively exploring the potential of Carbon Capture, Utilisation and Storage (CCUS) as a critical pathway for deep decarbonisation,” said Jindal.

He added that coprocessing industrial waste and by-products helps conserve natural resources, reduce disposal requirements and lower the environmental footprint across multiple sectors.

According to Jindal, sustainability is no longer limited to manufacturing processes but is increasingly influencing investment decisions, innovation strategies and long-term growth plans within the industry.

Echoing similar views, Dr Raghavpat Singhania, Vice President, CMA and Managing Director, JK Cement, said sustainable development extends beyond emissions reduction and must also focus on responsible resource utilisation and waste minimisation.

“Sustainability in the built environment cannot be measured by emissions alone. It is equally about how efficiently we use resources, how effectively we minimise waste and how responsibly we create the infrastructure that will serve future generations,” said Singhania.

He noted that the cement industry is advancing its sustainability agenda through greater resource efficiency, increased circularity, technological innovation and continuous improvements in manufacturing practices. As a key contributor to India’s infrastructure development, the sector has a critical role to play in balancing economic growth with environmental responsibility.

On the occasion of World Environment Day, industry leaders reaffirmed their commitment to supporting India’s climate goals while delivering the materials required for resilient, durable and sustainable infrastructure.

Concrete

Building a Greener Future Together

Published

7 days ago

June 4, 2026

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Environmental sustainability requires immediate action, not just long-term commitments and discussions. Recycling, circular economy practices, and technology-driven waste management can help industries reduce environmental impact while supporting sustainable growth.

Author: Jignesh Kundaria, Director and CEO, Fornnax Technology

World Environment Day serves as an important reminder that environmental sustainability can no longer remain confined to discussions, reports, or long-term commitments. The environmental challenges facing the world today demand immediate, measurable, and collective action. Across industries and communities, waste generation continues to outpace our ability to process it responsibly, placing increasing pressure on ecosystems, natural resources, public health, and the well-being of future generations.

One of the most significant shifts required today is a change in how society perceives waste. Rather than being viewed as a material to be discarded, waste must be recognised as a valuable resource that can contribute to both economic growth and environmental protection when managed through the right technologies and systems. This mindset forms the foundation of the circular economy model that countries across the world are increasingly adopting to reduce landfill dependence, recover valuable materials, and create more sustainable industrial ecosystems.

India has made meaningful progress in strengthening awareness around sustainability, recycling, and environmental responsibility over the past decade. Significant efforts are being made to formalise the recycling sector through improved infrastructure, technology adoption, policy implementation, and broader stakeholder participation. These developments are creating a stronger foundation for responsible waste management and resource recovery across the country.

However, achieving long-term environmental impact requires collaboration from all stakeholders. Industries, policymakers, technology providers, and communities must work together with greater accountability to strengthen recycling ecosystems, encourage responsible waste management practices, and create sustainable outcomes through consistent execution rather than temporary interventions.

As someone closely associated with the recycling industry, I firmly believe that technology will play a decisive role in addressing future environmental challenges. Advanced recycling systems have the potential to recover valuable resources, reduce pollution, minimise landfill burdens, and conserve energy, creating a more sustainable future for generations to come. This belief is deeply reflected in Fornnax’s motto, “Committed to Create a Green Future,” which embodies our commitment to building long-term environmental value through innovation and responsible action.

At the same time, technology alone cannot deliver meaningful change. Real progress requires intent, awareness, participation, and a shared sense of responsibility. Sustainable development can only be achieved when innovation is supported by collective action and a genuine commitment to environmental stewardship.

On this World Environment Day, let us move beyond conversations and take meaningful steps towards creating a cleaner, greener, and more sustainable planet. By embracing innovation, strengthening recycling ecosystems, and acting responsibly today, we can create lasting environmental impact and secure a better future for generations to come.

Concrete

JK Lakshmi Advances LC3 Cement Expansion

Company highlights commercial production and research partnerships

Published

1 week ago

June 1, 2026

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The meeting reviewed progress in limestone calcined clay cement (LC3) technology and its commercial adoption in India’s cement sector, focusing on low-carbon alternatives to conventional binders. JK Lakshmi Cement noted that limestone calcined clay cement can reduce carbon dioxide emissions by up to 40 per cent compared with conventional cement and said this reduction supports industry decarbonisation. The company highlighted that it was among the first two cement manufacturers in India to move LC3 into commercial production after the Bureau of Indian Standards approved the technology as a cement standard.

Vinita Singhania said the transition of LC3 from research to commercial production reflected collaboration between industry, academia and international institutions. Maya Tissafi acknowledged JK Lakshmi Cement’s role in advancing LC3 adoption in India and its contribution in taking the technology from laboratory trials to commercial implementation. Both representatives underlined the growing relevance of sustainable construction materials as India expands infrastructure and urban development.

The meeting explored continued collaboration with Swiss research institutions such as EPFL, EMPA and ETH Zurich alongside Indian academic partners and development organisations. JK Lakshmi Cement has been associated with the LC3 initiative since 2014 and worked with EPFL, IIT Delhi, IIT Madras, Development Alternatives and Technology and Action for Rural Advancement. The company conducted one of the earliest industrial trials of LC3 and recently announced commercial production of Green Pro LC3 cement from its Jaykaypuram plant in Rajasthan.

India remains the world’s second-largest cement producer and expansion of infrastructure, urbanisation and housing demand continue to support long-term sector growth, increasing interest in low-carbon technologies. The company reported an annual turnover of more than Rupees (Rs) 60 bn and current cement capacity of about 18 million (mn) tonnes (t) per annum, with a target of reaching 30 million (mn) tonnes (t) by 2030. Apart from grey cement, the company also makes ready-mix concrete, gypsum plaster, wall putty, primers, adhesives and fly ash blocks, and both sides concluded on the need for continued collaboration to develop sustainable construction solutions.