![]() Uses small amount of gypsum C4AF + 2CH + 14H C4(A,F)H13 + (A,F)H3 Ferrite + Calcium Hydroxide + Water Tetracalcium Hydrate + Ferric Aluminum Hydroxide (product #5) (product #6) like monosulfoaluminate amorphous Hardening – Strength gain with time – after final setĢC3S + 11H C3S2H8 + 3CH H = -500 J/g 2C2S + 9H C3S2H8 + CH H = -250 J/g Calcium silicates (C3S or C2S) + water Calcium silicates hydrate (C-S-H) + calcium hydroxide Amount of CH depends on proportion of C3S and C2S CSH - amorphous in nature, is an inexact composition, and is extremely fine (Colloidal).Ĭ3A + H2O reacts very fast C3A + H2O + CSH2 (Gypsum) reacts much slower C3A + 3CSH2 + 26H C6AS3H H = J/g Tricalcium Aluminate + Gypsum + Water Ettringite (product #3) Once CSH2 is depleted: C6AS3H C3A + 4H 3C4ASH12 Ettringite + Tricalcium Aluminate + Water Monosulfoaluminate (product #4)ġ0 Ferrite Phase: C4AF Forms same reaction as C3A but to a lesser degree Concrete phase will focus on early age characteristics, chemical admixtures, and hardened concrete properties.Ĭontinous binder phase: the cementitious matrix Binder effect on PCC behavior Affects permeability Affects strength Dispersed particulate phase: the aggregates Coarse: #4 to 1½” Fine: #100 to #4 Aggregates have a major effect on PCC behavior Serve as a filler Increase concrete modulus of elasticityģ } Cementitious Phase Portland Cement Water Admixtures Liquid MineralĤ Raw materials: limestone: CaCO3 Quartz: SiO2 Clays: Al2O3 and Fe2O3ĥ Cement Manufacture Quarrying – Raw materials Crushing Grinding MixingĬalcinated (1100C) Burned (1450C) Clinker is produced (10 mm size) Inter-ground with 5% gypsum (1-100 m) - most reactive ( 375min. Discussion of cementitious phase will focus on mechanical, chemical, and physical properties. ![]() Aggregates also influence the modulus of elasticity. ![]() Aggregates normally serve as the filler but help to reduce shrinkage (at early ages) and creep (at later ages). The binder phase normally controls the strength of the concrete. Aggregates are typically used in two factions: fines and coarse. 1 PC Cement Hydration PCC consists of binder and aggregates.
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