Another function of coffee grounds road construction materials

So Arulrajah and his team decided to collect coffee grounds from the university campus perimeter and oven dry them for five days. They then filter out the lumps of coffee grounds and mix them with steel slag. After adding an alkaline solution to both mixtures, they are compressed into cylindrical blocks. Tests by the researchers showed that the cylinders were strong enough to be used as subgrade material.

Researchers from Swinburne University of Technology said: "We collect an average of about 150kg of coffee grounds per week. We estimate that the coffee grounds collected from all the cafes in Melbourne each year could be used to build up to five kilometres of roads. This will reduce landfill and the need for quarry materials, says Arul Arulrajah: "When I see baristas throwing away coffee grounds, my thought is why not use this as an engineering material? Professor Arul Arulrajah and other researchers at the Centre for Sustainable Infrastructure at Swinburne University of Technology in Australia have focused on how materials such as broken bricks, glass and concrete can be efficiently reused in road construction. Recently, they tried to recycle coffee grounds near campus and use them as sustainable road construction materials.