Producing Pavers with Face-Mix

Face mix product fresh out of a KVM

Paver production in North America is changing drastically right now. Not only are there several new shapes and sizes and even colors, but there are also new ways being utilized to produce pavers that provide a much nicer looking installed paver at a lower cost to the producer of the product. I am, of course talking about utilizing a face-mix on a concrete pavers

Producing face-mix pavers is not all that new. In Europe it has been standard for decades. On the east coast of the U.S. It has been done for many years. However, in many North American markets this product is just emerging. This is a big change as there are many producers of pavers that make product on block machines. Block machines produce very attractive pavers, but it is not specifically what they are designed for. They quality of a block is determined by the dimensions, the quality of a paver is measured by its density. This difference becomes more significant when trying to produce more specialized pavers on a block machine. Face mix pavers fall deeply into this category.

To make a face mix paver you need a system that can lay down at least two layers of concrete in the pavervibration and compaction cycle. First you will place the base of the paver. Then you deliver and compact the face. The two layers must be properly prepare during the mixing and batching process to assure proper adhering between the face and the base.

So what is the difference between the face and the base? The base of the paver an be made of larger aggregate and less cement (as there is less surface area to cover). The base also needs little or no color, as it will never be seen once properly installed. The face of the paver is on the other hand made of fine materials, a greater amount of cement, nod more color. Colors are often even blended to create unique attractive surfaces, but that's another story.

Mixer Systems Plant for 3 color blend face-mix

There is significant material savings to be realized with face mix pavers, and the end product is more attractive and of higher quality. For producers that are currently producing concrete block and are looking for an avenue into this growing market it can be worth investigating a small board paver plant. Small board systems are ideal for meeting the paver needs of small to medium sized markets and can produce the face mix product the market is looking for.

KVM Machine with 2 Hoppers for Face-Mix

Face-mix paver are ideally made on a machine that is designed for the production of pavers, not block, as the process requires two separate feed drawers. The first must be able to precisely deliver the proper amount of base concrete into the form, while still leaving space for the finer face mix to be delivered by the second feed drawer.

There is often a two stage vibration to this process. The first vibration is delivered to get an initial compaction of the base concrete. The second vibration come following the delivery of the face-mix concrete blend. The second vibration is usually longer, stronger, and under pressure to insure that the pavers will meet the rigorous requirements of strength, and to assure that the face and base concrete are well bonded to each other.

The adherence between face and base mix is critical and can be very challenging. when the two layers separate, it is known as delamination. To be sure that this does not happen you need three important things. A good production machine, a good way to accurately batch and mix your concrete, and a good knowledge of what you are doing. Experience and practice make a huge difference.