Concrete 1 Flashcards
(13 cards)
what elements does concrete contain?
cement, water, aggregates (coarse/fine) admixtures, additives
what is Portland cement made up of?
calcium oxide + silicon dioxide + aluminium oxide
limestone, sands and clay
what are the stages of the manufacturing Portland cement?
1) blending and grinding of clay and limestone
2) pre heat
3) kiln
4) cooling and grinding
what is the reaction of cement and water called?
hydration reaction
what is artificial stone and how is it made?
when cement reacts with water and bind aggregate into hard, strong material (artificial stone)
what is dissolution?
when cement dissolves in the water making a porous solution
how are aggregates classified?
weight, source, shape and size
what are admixtures?
small components that are added to cement to change or more properties (added in water)
what are the different types of admixtures?
plasticisers (reduce water), super plasticisers, retarder (contort large pours), accelerators (increasing strength), air retraining agents (creating bubbles)
what is the function of additives?
they replace cement content while modifying the properties
what are the 2 type of additives?
type1 (inert additions), type 2 (active additions/ pozzolans)
what is are inert additions?
additions that improve the consistency and cohesiveness of the concrete (only use with self compacting concrete)
what are the different types of pozzolans?
PFA- burned coal from power plants
GGBS- rapid cooling of slag
CSF- particle of silicon condense from the fumes of production of silicon alloys
Metakaolins- burnt kaolin
