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According to the recent report, Global Construction 2020, India will be the third largest construction market by 2020 and is forecast to see a double-digit growth in the construction market. The 13th Five Year Plan projects an investment of 10 per cent of the national GDP into infrastructure which equates to a staggering Rs 60 trillion.

With the construction industry booming in India, the demand for building materials is on the rise. Sand is one of the key materials for construction industry, for which the demand is expected to reach 1,430 million tonne by 2020.

Scarcity of natural sand is the biggest concern for the construction industry in India and the local authorities imposing ban on the dredging of river sand further aggravates the problem. It is forecast that the naturally available sand will not be able to meet the required demand. One solution to this problem can be alternative sourcing of manufactured sand.

Natural sand

Natural sand is the weathered and worn out particles of rocks with various grades or size depending on the accounting of wearing. The natural and cheapest resource of sand is river.

Issues with natural sand:

• The river sand available today is deteriorated because of continuous dredging. It contains very high silt fine particles (as in case of filter sand).
• Presence of impurities such as coal, shells, bones, iron, silt and mica etc, makes it inferior for the use in cement concrete. The decay of these impurities, due to weathering effect reduces the life of the concrete.
• Removing sand from river bed impact the environment, as water table goes deeper and ultimately gets dry.
• Government has imposed ban on lifting sand from river bed because of the environmental issues

What is M-sand?

M-sand is basically crushed and graded form of aggregates obtained from hard stones like granite and subjecting them to further process.

The M-sand which is artificially produced from rock by using a vertical shaft impactor is a fine grinder subjecting rock to operations like impact and cleavage attrition and typically results in consistently good quality products having uniform gradation and shape.

IS Code requirements of M-sand:

• The surface texture of the particles should be smooth
• The edges of the particles should be grounded
• The ratio of fines below 600 micron in sand should not be less than 30 per cent
• There should not be any organic impurities
• Silt in sand should not be more than two per cent for crushed sand
• In manufactured sand, the permissible limit of fines below 75 micron shall not exceed 15 per cent.

Factors impacting the cost of natural sands

Sand is an expensive commodity for the construction industry. The price of sand varies from state to state depending on the demand and the availability. The average cost of natural sand in North India varies between Rs 3,000 to 4,500 per tonne whereas in the western and the Southern India, the cost varies between Rs 4,500 to 6,800 per tonne.

The cost of the sand is volatile and majorly impacted by four factors:

Ban on sand mining: The temporary ban on sand mining because of the rampant illegal mining and environmental issues leading to depletion of rivers is making the cost of sand volatile. This has led to the price rise from 25 to 400 per cent across different parts of the country. A truck load of sand (600 cu ft) today costs approximately Rs 15,000 in Haryana which was available for Rs 3,500 three years ago when mining was not banned in the state. In West Bengal, the cost of sand varies between Rs 1,600 and Rs 2,000 per truck. But in cities such as Bengaluru the cost of sand may go up to Rs 40,000 for a truckload depending on the quality of sand. The construction industry is facing huge financial losses as the state governments are delaying in issuing the orders to resume sand mining.

Illegal mining and sand mafia

The huge gap between supply and demand of natural sand has seen an increase in the illegal sand business in different states across India. Sand is difficult and heavy to transport, so construction companies prefer to source it from nearby areas, even from zones where it is not allowed. The sand mafia exploits the supply demand situation in different region by varying the prices of sand. Sand is a good source of revenue for state governments as it earns royalty from sand mining which are paid by the licensed miners. Illegal dredging is causing large-scale revenue losses to the state exchequer. This has led to complete ban on the sand mining by the most state governments.

Quality of sand

Presence of high amount of impurities in the sand makes it difficult to be used directly for concrete work. For getting the required fineness module, the sand must be sieved. In routine average wastage of sieving are about 35 per cent and extra labour cost involved. This increases the overall cost of the sand, making it costly for construction market.

Transportation of sand

Because of continuous dredging of sand from river bed, the resources are exhausting rapidly and good sand is not readily available, hence have to be transported from long distance. Continuous hikes in the diesel prices coupled with increase in the distance of transportation of sand from the mines to the construction site have increased the logistics cost of the sand.

Advantages of M-Sand:

• M-Sand has no impurities like silt, clay and pebbles and hence has no wastage, no additional labour cost for sieving and saves 15 to 20 per cent on overall cost.
• M-Sand possesses less curing time.
• M-Sand saves 2 to 8 per cent of cement consumption by using proper mixing ratio and saves 10 to 20 per cent on cost.
• M-Sand provides 30 per cent more durable and stronger product compared to other sands.
• M-Sand can be supplied in all measurements like tonnage, cubic feet and unit in sale bill.
• M-Sand is available throughout the year even during monsoon.
• M-Sand can be used as substitute for natural sand for producing eco-friendly pavers, blocks, and fly ash bricks.

Conclusion

Future trends: Currently, there is a shortage in the availability of natural sand either due to a ban on river sand mining or a shortage of natural sand within a particular area due to its geology. The M-sand offers the construction industry with a proven mechanism to increase the efficiency of its operations while at the same time maintaining the highest levels of product quality.

Availability of M-sand: The feedstock for the M-sand such as andesite, basalt, granite, limestone, sandstone and slags can be used to produce the M-sand. India possesses a wide spectrum of rocks spread throughout the country. Thus, the availability of manufactured sand will not be hampered as compared to natural sands.

Cost reduction: M-sand reduces the cost of construction as it is cheaper, contains no impurities and hence no wastage and provides higher durability and strength compared to natural sand.

Government regulation and policy: The Local Authorities/PWD/Government should make it mandatory to use M-sand in public construction work which would in turn create awareness and encourage the private players in the construction industry to go for M-sand as a substitute for natural sand.

The Government should come out with policy on sand that encourages the industry to set up more number of sand crushing units across all districts and states to meet the sand requirements of the construction industry.

CASE STUDY

Construction firm: MAAD Construction and Real Estate Developers.
MAAD Group of Company is one of the leading real estate developers in Vasai (near Mumbai), engaged in the construction of residential and commercial buildings.
M-Sand manufacturers: MAAD Mines and Minerals
Location: Mumbai

Issues

• A large proportion of the sand used in construction throughout Mumbai and the surrounding area was mined from river beds.
• Mumbai has recently seen the government introducing a ban on the mining of natural sand from rivers in order to protect the natural environment.
• The shortage of alternative natural sand reserves in the Mumbai area led to a requirement for this material to be imported from neighbouring states that do not face the same shortages. This has led to increased logistics costs of sands which ultimately causing cost escalation for concrete, mortar and plastering in building construction.

A substitute for natural sand

Faced by this challenging situation, MAAD decided to set up a manufactured sand production plant at Kanchad village in Thane district which is approximately 54 km from Vasai. This ensures MAAD is able to respond quickly to demands for material both internally and from its customers in and around Mumbai. This plant is a dual sand production plant that produces both concrete sand and plaster sand as per the requirement of IS 383.

The author is Senior Research Analyst with Beroe Inc, a global provider of customised procurement services to Fortune 500 organisations.