Download - High Performance Concrete
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*HIGH PERFORMANCE CONCRETE
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*SALIENT FEATURES OF HIGH PERFORMANCE CONCRETE
HIGH WORKABILITY
HIGH COMPRESSIVE STRENGTH
SEVERE ENVIRONMENT
COST
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*DEFINITION
A CONCRETE WHICH MEETS SPECIAL PERFORMANCE AND UNIFORMITY REQUIREMENTS THAT CANNOT ALWAYS BE ACHIEVED ROUTINELY BY USING ONLY CONVENTIONAL MATERIALS AND NORMAL MIXING,PLACING AND CURING PRACTICES
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SELECTION OF MATERIALS
SELECTION OF SUITABLE INGREDIENTS
DETERMINATION OF QUANTITIES
CAREFUL QUALITY CONTROL
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*CEMENT
LITTLE AMOUNT OF C3A
FINELY GROUND
FAIR AMOUNT OF C3S
FINE AGGREGATES
RIVER SAND AND CRUSHED STONES
COARSER SAND
MINIMUM VOID RATIO
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* COARSE AGGREGATE STRONGEST COMPONENT
SIZE NOT EXCEEDING 20MPa
CUBIC IN SHAPE
NOT FLAKY OR ELONGATED
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IMPORTANT INGERDIENT
BINDING AGENT
EXCESS WATER IS UNDESIRABLE
WATER
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*CHEMICAL ADMIXTURES
IMPROVE WORKABILITY
DECREASE IN WATER REQUIREMENT
TYPES OF CHEMICAL ADMIXTURES:
PLASTICIZERS SUPER PLASTICIZERS RETARDERS AIR ENTRAINING AGENTS
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MINERAL ADMIXTURESCEMENT MATRIX-DENSER AND STRONGERTYPES OF MINERAL ADMIXTURES FLY ASH SILICA FUME CARBON BLACK POWDER ANHYDROUS GYPSUM BASED MINERAL ADMIXTURES
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BEHAVIOUR OF FRESH HPC
WORKABILITY
VERY GOOD
PUMPED VERY WELL
WITHOUT SEGREGATION AND VOIDS
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*SETTING TIME
DEPENDS ON APPLICATION
WATER REDUCING ADMIXTURES
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*BEHAVIOUR OF HARDENED HPC
SHORT TERM PROPERTIES:
COMPRESSIVE STRENGTHTENSILE STRENGTH
LONG TERM PROPERTIES:
DURABILITY(POROSITY,PERMEABILITY,FREEZE-THAW RESISTANCE AND ABARASION RESISTANCE)CREEP AND SHRINKAGE
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*STRENGTH
CONSTITUENT MATERIALS
METHOD OF TESTING
RATE OF LOADING
CURING TECHNIQUES
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*COMPRESSIVE STRENGTH
28 DAYS STRENGTH UPTO 80 Mpa90 DAYS STRENGTH UPTO 130 MpaFUTURE-140MPa
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*TENSILE STRENGTH
GOVERNS THE CRACKING BEHAVIOUR
DIRECT TENSILE TEST
SPLIT TENSILE TEST
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DURABILITY CHARACTERISTICS
LOW PERMEABILITY
STEEL PROTECTED
ABRASION RESISTANCE
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WHEN TO USE HPC
SEVERE EXPOSURE CONDITIONS
INCREASE DURABILITY
PREVENT DETERIORATION OF CONCRETE
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*APPLICATIONS
BRIDGES
HIGH RISE BUILDINGS
TUNNELS
PAVEMENTS
NUCLEAR STRUCTURES
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*CASE STUDY:JOIGNY BRIDGE
BUILT ACROSS RIVER YONNE
THREE SPAN BRIDGE
HEIGHT OF 220m
WIDTH OF 15.8m
FRENCH CODES
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*REDUCTION IN CONCRETE VOLUME
28 DAYS STRENGTH OF 70MPa
PUMPING
SUFFICIENT SETTING TIME
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*CONCRETE STRENGTH-91.7MPa AND 65.5MPaTENSILE STRENGTH-5.1MPaFIRST BRIDGE WITH 60MPaCOMPLETED IN 1989
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*ADVANTAGESREDUCTION IN SIZE OF STRUCTURAL MEMBERSSPEED OF CONSTRUCTIONWORKABILITY AND PUMPABILITYECONOMICAL MATERIAL IN TERMS OF TIME AND MONEY
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*HIGHER SEISMIC RESISTANCE
IMPROVED DURABILITY
ABRASION RESISTANCE
HIGH TENSILE STRENGTH
REDUCED MAINTENANCE COSTADVANTAGES(CONT..)
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*LIMITATIONAN EXTENDED QUALITY CONTROL
COST SPECIAL CONSTITUENTS
MANUFACTURED AND PLACED CAREFULLY
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*CONCLUSIONS
DURABILITY CONSIDERATIONS
INITIAL COST IS HIGH
REDUCED SIZE OF STRUCTURAL MEMBERS
PRECAST PRODUCTS
EFFECTIVE UTILIZATION OF INDUSTRIAL WASTES
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