02-02-2012, 11:24 AM
Reactive Powder Concrete
[attachment=17033]
What is it?
What does it do?
What is its applicability?
What kind of research is being done on it?
Why should we care?
Where is it headed?
Current High Strength Concrete
High performance concrete can be made to have strengths in excess of 30,000-40,000 psi.
Use either a mix of superplasticizer, silica fume, and extra-hard aggregate (calcined bauxite or granite) or “Macro Defect Free polymer pastes”
Still brittle, low ductility
RPC Composition
RPC is able to obtain its improved properties by using a very dense mix, consisting of fine particles and fibers.
Low w/cm ratio : 0.16 to 0.24 (as low as 0.13)
Type 20M (like type II) Portland cement (no C3A less HoH)
Silica fume (25% by weight)
Water
High dosages of superplasticizer
Fine quartz sand (150-600μm) (SG=2.75)
Steel fibers (2.5-10% by volume) for toughening
No rebar needed!
Cured in steam bath for 48 hrs @ 190ºF (88ºC) after initial set, placed under pressure at the molding stage
RPC Applications
RPC’s properties, especially its high strength characteristic suggests the material might be good for things needing lower structural weight, greater structural spans, and even in seismic regions, it outperforms normal concrete. Below are a few examples of real-world applications, though the future possibilities are endless.
First bridge that used RPC was a pedestrian bridge in Sherbrooke, Quebec, Canada. (33,000 psi ~230MPa) It was used during the early days of RPC production. Has prompted bridge building in North America, Europe, Australia, and Asia.
Portugal has used it for seawall anchors
Austrailia has used it in a vehicular bridge
France has used it in building power plants
Qinghai-Tibet Railway Bridge
Shawnessy Light Rail Transit Station
Basically, structures needing light and thin components, things like roofs for stadiums, long bridge spans, and anything that needs extra safety or security such as blast resistant structures
[attachment=17033]
What is it?
What does it do?
What is its applicability?
What kind of research is being done on it?
Why should we care?
Where is it headed?
Current High Strength Concrete
High performance concrete can be made to have strengths in excess of 30,000-40,000 psi.
Use either a mix of superplasticizer, silica fume, and extra-hard aggregate (calcined bauxite or granite) or “Macro Defect Free polymer pastes”
Still brittle, low ductility
RPC Composition
RPC is able to obtain its improved properties by using a very dense mix, consisting of fine particles and fibers.
Low w/cm ratio : 0.16 to 0.24 (as low as 0.13)
Type 20M (like type II) Portland cement (no C3A less HoH)
Silica fume (25% by weight)
Water
High dosages of superplasticizer
Fine quartz sand (150-600μm) (SG=2.75)
Steel fibers (2.5-10% by volume) for toughening
No rebar needed!
Cured in steam bath for 48 hrs @ 190ºF (88ºC) after initial set, placed under pressure at the molding stage
RPC Applications
RPC’s properties, especially its high strength characteristic suggests the material might be good for things needing lower structural weight, greater structural spans, and even in seismic regions, it outperforms normal concrete. Below are a few examples of real-world applications, though the future possibilities are endless.
First bridge that used RPC was a pedestrian bridge in Sherbrooke, Quebec, Canada. (33,000 psi ~230MPa) It was used during the early days of RPC production. Has prompted bridge building in North America, Europe, Australia, and Asia.
Portugal has used it for seawall anchors
Austrailia has used it in a vehicular bridge
France has used it in building power plants
Qinghai-Tibet Railway Bridge
Shawnessy Light Rail Transit Station
Basically, structures needing light and thin components, things like roofs for stadiums, long bridge spans, and anything that needs extra safety or security such as blast resistant structures
