The recycling of concrete
What is concrete? concrete is an artificial material made of pebbles, gravel and sand, merged together by means of a generally hydraulic binder.
Is Concrete Recycling possible?
Yes, reusing recycled concrete to make concrete again is possible. Concrete manufacturing requires cement, water, sand and gravel. These last two constituents can come from concrete waste and replace natural materials. Nevertheless, recycled concrete does not have quite the same properties as conventional concrete. There is a lowering of elasticity (less elastic modulus), and a greater shrinkage (increased withdrawals, before and after setting). But this does not provide an increase in the risk of cracking.
From a technical point of view, the experimental sites have made it possible to adapt the formulas, to prove the ease of drawing air into the concrete, to demonstrate that the manufacturing, the transport and the implementation did not generate any problems. They also allowed raising questions of logistics.
For reusing recycled concrete, it is necessary to be able to store the materials on the spot, because the volumes of aggregates available are more random since they depend on the sites of demolition. To counter this difficulty, the project partners are considering the idea of mixing recycled materials / natural materials directly into quarries. The idea is to provide a more fluid supply to construction sites while proposing different rates of incorporation of recycled materials depending on the types of concrete requested.
How is recycled concrete produced, and what are the obstacles to its development?
The first step is to put selective deconstruction techniques in place to sort concrete waste among other materials. The concrete blocks resulting from the demolition are then crushed, before going to the iron removal and the screening. Complementary steps, such as detection and separation of unwanted particles, can be implemented to purify the deconstructed materials.
The use of recycled aggregates for filling road platforms is already widespread: 80% of demolition concrete is used in the road. But this remains very limited in the building. To go further, we must work to recycle concrete in concrete. The main issue is to show that more recycled concrete can be used without modifying its implementation compared to traditional concrete.
Today, all mature industries are recycling their materials at the end of their life, and it will soon be the same for the concrete sector. It will soon be possible to produce recycled concrete with the same level of strength and durability as conventional concrete.
For more information about recycling concrete or concrete products, Danterr is here to answer all your questions. Please visit our website or give us a call on: 1800 262 383.