Reactive Powder Concrete

PRESENTED BY Ambudhi Goel (M.Tech)

INTRODUCTION

MATERIALS OF RPC

MECHANICAL PERFORMANCE AND DURABILITY OF RPC

COMARISION OF RPC AND HPC

APPLICATIONS OF RPC

BENEFITS

LIMITATIONS OF RPC

CONCLUSION

• Cement • Sand • Silica fume• Steel fibers• Super plasticizer

Elimination of coarser aggregates to enhance homogeneity

Utilization of the pozzolanic properties of silica fume

The optimal usage of super plasticizer to reduce w/c and improve workability

Application of pressure (before and during setting) to improve compaction

Addition of small-sized steel fibers to improve ductility

Silica fumes- These are also called as micro silica, it is a dark gray

cementitious material composed of at least 85% of ultra fine amorphous non crystalline particles, more finer then the average Portland cement particles.(0.1-0.3um).with minimum specific surface area of 15000m2/kg

Because of its extremely fine particles size it gives the properties of good pozzalona.

We know as fineness increases there is increase in the strength of the concrete.

Because of finer particles pores are also reduced, there by decreasing the penetrability.

Steel fibers

To improve the tensile strength of the concrete & to minimize the Micro-cracks these steel fibers are added.

If the fibers are uniformly closed and dispersed in matrix increases the dynamic property & arrest the crack.

Round steel fibers of diameter 0.25mm-15mm are generally used.

Use of steel fibers makes significant improvements in flextural, impact& fatigue strength of concrete.

Super plasticizers are the admixtures which are added to the concrete mix to increase the workability keeping w/c ratio constant.

Using polycrylate based increasing workability upto 25%.

As a consequence of increased strength, with lower w/c ratio it also permits in the reduction of cement content, which seems to be economical.

RPC 200RPC 200 RPC 800RPC 800

Compressive strength(using Quartz sand ) Compressive strength(using Quartz sand ) MPaMPa

170-230170-230 490-680490-680

Compressive strength(using Steel Compressive strength(using Steel aggregate ) MPaaggregate ) MPa

-------------- 650-810650-810

Flexural strength MPaFlexural strength MPa 30-6030-60 45-14145-141

The RPC family includes two types of concrete• RPC 200 • RPC 800 Comparison of RPC 200 and RPC 800

RPC

50mm cubes for Compressive strength ( IS 516) 40x40x160 mm prisms for flexural strength (IS

516 ) 150 mm cubes for Water absorption (BS 1881:122-

1983) 150mm cubes for Non destructive water

permeability test Resistance to chloride ions penetration test on

100mm dia discs

HPC 100mm cubes for Compressive strength ( IS 516) 100x100x500 cm beams for flexural strength (IS

516) 150 mm cubes for Water absorption ( BS

1881:122-1983) 150mm cubes for Non destructive water

permeability test Resistance to chloride ions penetration test on

50mm dia discs

Compressive strength of RPC and HPC

Water absorption of RPC and HPC

Surface water permeability of RPC and HPC

HPCHPC RPCRPC

Compressive strength MPaCompressive strength MPa 8080 200200

Flexural strength MPaFlexural strength MPa 77 4040

Modulus of elasticity GPaModulus of elasticity GPa 40 40 6060

Fracture toughness J/mFracture toughness J/m22 <10<1033 30x1030x1033

Abrasive wearAbrasive wear 2.5 times lower2.5 times lower

Water absorptionWater absorption 7 times lower7 times lower

Rate of corrosionRate of corrosion 8 times lower8 times lower

Chloride ions diffusionChloride ions diffusion 25 times lower25 times lower

Sherbrooke FootbridgeLocation:sherbrooke,Quebec,CANADA

Completed in:1997

Structural type:Truss bridge

Fuction/usage:pedestrian bridge.

Construction of the sherbrooke bridge

SHERBROOKE BRIDGE

Project Location: Sherbrooke, Quebec, CanadaDuctal Volume: 42 m3

this pedestrian bridge spans 60 m (190 ft) with a deck thickness of just 3 cm (1¼").

RPC is a better alternative to High Performance Concrete

It has the potential to structurally compete with steel.

Its superior strength combined with higher shear capacity results in significant dead load reduction and limitless structural member shape.

With its ductile tension failure mechanism, RPC can be used to resist all but direct primary tensile stresses. This eliminates the need for supplemental shear and other auxiliary reinforcing steel.

RPC provides improve seismic performance reduces inertia loads with lighter members reduces the cross sections of members provides higher energy absorption.

Low and non-interconnected porosity diminishes mass transfer making penetration of liquid/gas or radioactive elements nearly non-existent.

The least costly components of conventional concrete are basically eliminated or replaced by more expensive elements.

The fine sand used in RPC becomes equivalent to the coarse aggregate of conventional concrete

The Portland cement plays the role of the fine aggregate and the silica fume that of the cement of conventional concrete.

The mineral component optimization alone results in a substantial increase in cost over and above that of conventional concrete (5 to 10 times higher than HPC)

RPC should be used in areas where weight savings can be realized

Since RPC is in its infancy, the long-term properties are not yet known.

A maximum compressive strength of 198 MPa was obtained. This is in the RPC 200 range (175 MPa -225 Mpa)

The maximum flexural strength of RPC obtained was 22 MPa, lower than the values quoted 40 MPa. A possible reason for this could be the higher length and the diameter of fibre used in this study.

A comparison of the measurements of the physical, mechanical and durability properties of RPC and HPC shows that RPC has better strength (both compressive and flexural) and lower permeability compared to HPC

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