South African company Poynting has developed and patented a tough concrete called HeliCrete, which is suitable to protect valuable assets from criminals.
The concrete was developed as part of Poynting’s MagiCube secure concrete container project. The containers are used to fight the scourge of battery theft and base station vandalism in South Africa.
The MagiCube design considers cable access, weather protection, heat dissipation, and protection against theft and vandalism.
Poynting’s HeliCrete makes it near impossible for criminals to break and access an enclosure.
Andre Fourie, Chairman at Poynting Group, provided a summary of the tests they did on three different types of concrete to demonstrate their strength.
The concrete tests were:
- 100 MPa with 19 mm rebar spaced 75 mm apart – it took 8 hits with a sledgehammer to destroy the concrete block.
- 100 MPa with 19 mm rebar spaced 300 mm apart with helices/springs – it took 50 hits with a sledgehammer to destroy the concrete block.
- 100 MPa geopolymer concrete with metal shavings (HeliCrete solution) – It took 200 hits with a sledgehammer to damage the concrete block.
The geopolymer cement costs the same as normal cement, but sets much faster and is much harder.
It proved more resilient than normal concrete, and when combined with the HeliCrete process proved to be up to 20-times more difficult to break.
The HeliCrete test block was still intact after 200 blows – and it would take much longer to get into when used as part of an enclosure.
“HeliCrete allows us to make an enclosure with much-reduced dimensions and weight while retaining or improving on its strength,” said Fourie.
Making the HeliCrete solution stronger
Fourie said they used spirals of mild steel metal shavings rather than “springs” (high tensile steel helices) in their HeliCrete tests, and that springs are even better.
However, Poynting has not tested springs with the geopolymer cement in block form yet.
He said Poynting is already using spring-based 100MPa HeliCrete in their “next generation” products, with excellent results.
The images below show samples of HeliCrete using spiral shavings, before casting and after battering.