The construction industry relies on many raw materials and minerals for its operations – stone, soil, steel and sand are among the most consumed natural elements in the industry. A growing global population means that more buildings need to be constructed, so some contractors have started to look for sustainable alternatives to these materials.
Sand is a natural material that may seem abundant, but it is being depleted quicker than it is formed by the environment. Leading engineering firms and contractors are exploring sand alternatives for use as aggregates in concrete. These efforts are minimising sand depletion and enabling existing sand to be recycled for other construction projects.
The world uses around 44-billion tonnes of sand every year for construction, land reclamation, roadways and to produce concrete. Not all of it is suitable for construction – desert sand is too fine and beach sand can contain unwanted contaminants such as seashells and plastic pollution. Rivers and quarries are the primary sources of sand used in the building industry.
Sustainable alternatives to sand
Some contractors have started to use plastic waste as an alternative. Non-recyclable bits of plastic waste are ground up into small pellets which are then used as the fine aggregate in a concrete mixture. This process has started to gather momentum in India and the United Kingdom.
While the long-term effects of using plastic in concrete are not fully known, researchers have studied its durability, thermal properties and fire resistance. Plastic is a good alternative to sand and also allows contractors to use up non-recyclable plastic waste in the process.
Contractors are also exploring the use of other sand-like aggregates, including crushed glass and quarry dust. Glass bottles can be recycled but small fractions of broken glass cannot. These bits of broken windows, mirrors, tubes and bottles can be crushed into a sand-like texture. Quarry dust from rock blasting and granite excavation also has similar properties to sand and crushed glass.
Where alternatives to sand cannot be found, contractors have started to recycle sand from old construction projects and sites. Recycling old building materials such as sand, concrete and rubble is starting to gain traction around the world. By embarking on sustainable campaigns, engineers, architects and construction practitioners can minimise their impact on the environment and reduce consumption of natural materials.
LafargeHolcim is a leading building materials and solutions company that has been operating in international markets for decades. We produce cement and aggregates for construction projects, ranging from small affordable housing developments to large-scale infrastructure projects such as high-rise buildings, dams and bridges.
LafargeHolcim Tanzania has been supplying the country and neighbouring countries with our world-class Tembo cement brand for over 30 years. Our head office and fully-integrated plant are located in Mbeya, Southwest Tanzania.
At LafargeHolcim Tanzania, we believe customers come first. We listen to your specific requirements to supply and develop the best solutions for your needs. As the new leader in building materials, you can also rely on our cutting-edge research and development capabilities that have resulted in the finest materials for your construction projects, whether large or small.