Roller compacted concrete (RCC) pavements offer a competitive and long-term choice for developers. The benefits the material offers are seeing its increasing use for roads, industrial pavements, heavy-duty parking and storage areas, according to Andrew Minson, executive director of MPA The Concrete Centre.
First developed in the 1970s, when the Canadian logging industry needed strong pavements that could withstand huge loads and specialised equipment, RCC is now widely used for ports, industrial and heavy-duty parking areas. It is increasingly being considered as an economic, long-term road surfacing material.
Strength and performance
RCC uses the same basic ingredients as conventional concrete - cement, water and aggregates. However, by using a drier mix that is rigid enough to be compacted by vibratory rollers, RCC is constructed without joints, contains no dowels or steel reinforcement and needs no finishing. It combines the strength, long-term performance and minimal maintenance of conventional concrete with the economy and simplicity of construction that is associated with asphalt laying.
For roads RCC offers further advantages that include the ability to span localised soft subgrades, resistance to deformation under heavy loads, and it will not soften under high temperatures.
How RCC works
Large mixers blend the RCC that is transported to site and discharged into an asphalt paver. This places the materials in layers up to 250 mm thick and 13 m wide. Compaction starts immediately after placement and continues until the pavement meets density requirements. Curing ensures a strong and durable pavement.
In the UK, RCC is increasingly being considered for truck lanes and motorway widening projects, and as an economic alternative to fully flexible pavements.
Cheaper and faster to construct
The benefits of RCC have been underlined by research carried out at Sheffield University. Researchers have developed a RCC with recycled steel fibres from waste tyres that is 12% cheaper than conventional road construction and 15% faster to construct. Additionally, over the lifetime of the RCC pavement there is a 40% reduction in energy consumption.
RCC has significant potential for the UK road network. It is economic and fast to lay, has long-term performance with minimum maintenance and can use waste materials for its construction. Moreover, at the end of its life span, it can be crushed and recycled for a new pavement.
Read the article online at: https://www.worldcement.com/europe-cis/15102013/roller_compacted_concrete_is_top_choice_for_pavements_292/