08-02-2010, 07:01 AM
REACTIVE POWDER CONCRETE
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INTRODUCTION
A composite material & ultra high strength with mechanical properties.
Mixture of fiber reinforced, super plasticized, silica fume, cement & quartz sand
with very low water cement ratio.
Quartz sand used instead of ordinary aggregate. Therefore increases compressive
strength.
COMPOSITION
It is composed of similar modulus of elasticity and size increasing homogeneity
reducing differential tensile strain.
The material having the largest particle size in RPC is the sand.
The higher the density, the greater the strength & lower the permeability.
Water cement ratio used in RPC ranges from 0.15 to 0.25
Strength more than 200MPa achieved , cured at 90 degree celsious.
Components with functions parameters
Components
Sand
Cement
Quartz powder
Silica fume
Steel fibers
Superplasticiser
Function parameters
Give strength to aggregate
Binding material
Maximum reactivity during heat-treating
Filling the voids
Improve ductility
Reduce water binding
PROPERTIES OF RPC
1. COMPRESSIVE STRENGTH
Higher compressive strength than HPC
It is a factor linked with durability of material.
Maximum compressive strength of RPC is approximately 200MPa.
2. FLEXTURAL STRENGTH
Plane RPC possess high flextural strength than HPC
By introducing steel fibers, RPC can achieve high flextural strength.
5. RESISTANCE TO CHLORIDE ION PENETRATION
Increases when heat curing is done in concrete
Heat cured RPC show higher value than normal cured RPC.
6. HOMOGENITY
Improved by eliminating all coarse aggregates.
Dry components for use in RPC is less than 600 micro meter.
7. COMPACTNESS:
Application of pressure before and during concrete setting period.
8. MICROSTRUCTURE:
Microstructure of the cement hydrate can be changed by applying heat treatment
during curing.
9. MATERIAL DUCTILITY:
Material ductility can be improved through the addition of short steel
fibres.
2. CONTAINMENT OF NUCLEAR WASTE
Used for isolation and containment of
nuclear wastes.
It has been used for blocking &
stabilization of containment waste.
BENEFITS
It has the potential to structurally compete with
steel.
Superior strength combined with higher shear
capacity result in significant dead load reduction.
RPC can be used to resist all but direct primary
tensile stress.
Improved seismic performance by reducing
inertia load with lighter member .
Low &non-interconnected porosity diminishes
mass transfer, making penetration of liquid/gas non-existent.
CONCLUSION
It has immense potential in construction due to its superior, mechanical &durability
properties.
RPC has ultra dense micro structure , giving advantageous water proofing &durability
characteristics.