CEM-PAVE Roller Compacted Concrete (RCC) was used as a supporting base layer for the installation of large decorative granite paving slabs. This contract formed part of a larger regeneration scheme for North Somerset Council being carried out by Skanska Infrastructure Services.

Due to the nature of the slabs and the need for the paved area to be able to withstand HGV movements, the design of the support layer needed to be rigid. Additionally, North Somerset Council did not want the aesthetics of the granite paving being marred by the reflective construction joints. This created an issue using conventional concrete or flexible asphalt.

The designers then decided to look at a heavy steel fibre concrete with substantial steel reinforcing to enable a larger slab to be cast, thus trying to minimize shrinkage and reflective joints. However, due to the high cost and slower installation time of this design it was not a viable option for the project.

Skanska contacted CEMEX Paving Solutions and within one week of discussions a solution was agreed. The nature of RCC’s aggregate grading and the lower water to cement ratio means that the product is less prone to shrinkage. The aggregate interlock creates high sheer resistance especially at the joints, negating the need for steel reinforcing. This was the ideal solution to minimise reflective construction joints and support any future HGV movements on the paving.

With the delays in finalising the design and with works already underway, there was no loss of time incurred due to the speed of installation compared to conventional wet poured concrete.

CEMEX Paving Solutions were able to complete the installation in three days as opposed to the three to four weeks which is usually required for the wet pour concrete. A curing period of seven days from the first day of paving was agreed to allow any minimal shrinkage to take place. The surface was inspected for any possible issues and then paving of the granite blocks began.

Due to the inexpensive nature of RCC, CEMEX were able to save the client both time and money. Works were able to continue on site within 48 hours of the RCC being installed due to the quicker curing of the material, this allows for light trafficking. With no need for fibres or steel reinforcing, the material costs were lower than the original proposed design.