New research into ultra-high performance concrete (UHPC) could transform the way buildings, bridges and other high-stress projects are constructed.
UHPC, like normal concrete, contains cement, sand and chemical additives, but is made with different proportions that produce a denser-packed concrete that requires no steel reinforcements.
The Precast/Prestressed Concrete Institute (PCI) is supporting research into new forms of UHPC that are more cost-effective and can use materials found in local areas near construction projects. The PCI has developed guidelines for UHPC mixtures and how they are produced.
A project team has tested prototype designs built with UHPC. They have found that initial costs of producing UHPC are high, but because structures such as concrete flooring require no steel, the overall cost is competitive with steel-reinforced concrete.
A UHPC design concept used a cross-section 60 ft span, 22-inch deep precast and prestressed floor panel that required no steel apart from prestressing strands. In the shape of a pi (π) symbol, this long-span panel could be used in multi-storey car parks and is strong enough to need no supporting columns. The narrow height can incorporate the plumbing and electrical systems, making efficient use of space.
UHPC could benefit construction projects where long spans and durable concrete flooring are required. They can be installed at competitive costs to concrete and steel alternatives. As well as floors, UHPC is suitable for other high-stress applications such as bridges and walkways.
UHPC promises the benefits of more efficient use of materials, better space utilisation and long-term performance enhancement.