Revolutionising Construction
The use of concrete in construction has come a long way and, with it, the choice of equipment.

“Switching from the use of volumetric batching concrete to weigh batching concrete, from M15 grade concrete to M25 and then to M60 and finally today to the M80 grade of concrete, and also from site-mix concrete to ready-mix concrete (RMC) to self-compacting concrete, has impacted the choice of construction equipment,” observes Suneet Gupta, Concrete Technologist.

For instance, he points out: “Concrete used to be transported manually; now it is transported mechanically. Compaction used to be hand-driven; now, it is vibrator-driven. Hand tools used to help finish a job but now finishing is done mechanically. And where self-compacting concrete is used, the role of labour has all but been eliminated with enhancement to the quality of the outcome and speed of work. Taller buildings are necessitating boom pumps and, in turn, these are reducing the role of labour.”

Impact of higher grades

Recent revisions to the construction regulatory code, that emphasises durability and quality, and improved access to micro-silica and the newest superplasticisers have popularised M60 and higher grades of concrete [in India], says Mohit Jajoo, CEO, Shubhashish Homes. “To meet these requirements, the demand for machinery producing precise, consistent mixes has increased. In response, producers of concrete equipment have created cutting-edge batching and mixing systems that guarantee the highest level of quality assurance.”

Now that high-grade concrete is being manufactured in most metro cities, Anil K Banchhor, Managing Director & CEO, RDC Concrete, points out, “The regular pan-type mixer doesn’t work effectively. High-grade concrete contains a lot of ultrafine materials, mineral admixtures like fly ash and ground granulated blast-furnace slag, necessitating a higher cement weigher capacity in batching plants. Twin-shaft mixers as well as high-capacity planetary mixers are required with bigger cementitious material weighers. So far, only Simem India, Sicoma and Ajax are making planetary mixers of 1 cu m. We need more players to enter this space with higher capacity – 2 and 3 cu m – batch size planetary mixers.”

Also, he continues, “The distribution of cementitious materials and the admixture should be at two points instead of only one for better mixing and a shorter mixing time. At present, mixers have only one dispersal point for cement and water. But for faster dispersion, the cementitious materials and water should each get discharged through two points.”

Another issue is that concrete tends to stick in the discharge hopper, according to Banchhor. “Concrete discharge hoppers should be made of abrasion-resistant material like hardox so that they don’t abrade quickly and last longer. Also, batching plant manufacturers should provide Teflon sheet liners inside cement weighers, aggregate waiting hoppers and in the sand bin to reduce the abrasion and for better flow.”

Operational gaps

We still grapple with the frequent breakdown of essential concreting equipment, particularly pumps and batching plants, rues Anil Reddy, MD, Concorde. “Unfortunately, the challenge is intensified by the unavailability of spare parts locally, necessitating their sourcing from other states, primarily Maharashtra. The absence of local service engineers adds to delays and disruptions. Also, the cost of boom placers is notably high and the acquisition process is cumbersome. Streamlining the material flow process is also essential, as concrete can sometimes be rigid and manual intervention should be minimal.”

To address these issues, he proposes transitioning from manually operated batching plants to fully automated ones. “Producing only 36 cu m per hour is insufficient to effectively meet the needs of the market. An automated machine would do better.”

To achieve long-term, irreversible improvements in operations, Reddy advocates the introduction of better equipment with enhanced features such as a live monitoring system, GPS in transmit mixers and sensors to ensure the right ratio of ingredients goes into the mix. “Implementing live monitoring of the mixing process is crucial for safety and quality. Establishing routine quality control checks by a trained team would also help. Batching plant operations should prioritise safety, with frequent visits from local licensed authorities to ensure compliance. Incorporating hydro-cyclone sand washers and increasing pump capacity are steps towards efficiency. The frequent calibration of equipment for accuracy and the manufacturing of robust machines is key for efficient production. Additionally, lowering operation and maintenance costs would significantly help.”

Printed concrete

Of late, 3-D printing of concrete has entered the industry, says Gupta. “L&T made the first such building (a post office) in Bengaluru and is now building five buildings with the technology in Chandigarh. 3-D printing reduces the human resource need to just five or six persons while the building is completed in a matter of days.

Of course, specialised printers are needed.”

“3-D printing concrete technology is the latest trend in construction technology,” agrees Reddy. He feels this innovative approach is particularly well-suited to affordable housing communities as it delivers cost and time savings compared to traditional construction methods and minimises waste, thereby reducing the environmental footprint of construction projects. Such advancements bode well for the construction industry.

Bridging the gaps: The concrete industry’s wishlist

What is the concrete equipment segment lacking with a view adequately expand to support the construction industry?
Regulatory framework:
“High taxes narrowing profit margins and complex regulations are discouraging potential investors from the concrete industry,” says Mohit Jajoo, CEO, Shubhashish Homes. “Decision-makers and industry stakeholders must work together to promote more benevolent tax and regulatory frameworks and encourage investment and growth to close this gap.”

R&D: Fierce competition from Chinese equipment producers and domestic imitations, as well as cost-related difficulties and infrastructure delays, are some other obstacles, continues Jajoo. “Encouraging innovation and R&D across the entire industry would help introduce cutting-edge equipment that can compete on both the price and quality fronts.”

Quality control: Another issue is the use of subpar concrete blocks and unreliable concrete block machines, he adds. “Such actions jeopardise the durability and safety of construction projects and damage the reputation of the industry. Stringent regulatory standards and rigorous quality-control protocols must be enforced to ensure the exclusive use of top-tier tools and materials.”

Skill development: “Labour shortages are another concern, especially considering the demanding and tedious nature of equipment handling,” says Anil Reddy, MD, Concorde. “Establishing training institutions for professionals would help ensure that the workforce is well-equipped to effectively operate and maintain these advanced machines.”

Concreting in small-town India

“The onsite mixing of concrete is still common in tier 2 and 3 towns”, says Aditya Ostwal, Managing Director, Dhanshree Ready Mix Concrete. “Initially, users didn’t trust RMC because they had no product awareness or knowledge. We have conducted many seminars for contractors, engineers and architects to create awareness. It takes time to make inroads in those areas but the outlook has changed in the past three years. Users are beginning to trust RMC. We used to supply about 200-300 cu m per month in 2020; now, we supply 5,000 cu m per month.”

As for the demand for concrete pumps. Ostwal points out, “Moli (mobile + line) concrete pumps, wherein the pump is assembled in the van, make it easier to transport the pump. At present, the concrete pump must be attached to a towing vehicle, typically a tochan tractor with the pipeline loaded in the tow vehicle. Prior to moving, the towing vehicle and the pump must be welded, which can pose a traffic safety risk. In future, Moli concrete pumps will definitely become the preferred option.”