Concrete Flashcards
Concrete
Aggregate, Cement, Water, and Admixture
Portland Cement
Lime, Silica, Alumina, Gypsum
How long does Cement take to reach full strength?
28 Days
Isolation (expansion) Joint
Provide for lateral movement between slabs. Extend the full depth of the Concrete
Concrete Qualities
Strength, Durability, Stability, Availability, Adaptability, and Low-cost
Properties of Concrete
Constituents, Skills used in placing
Concrete resistance to freeze/thaw and deicing chemicals
Apply admixtures
Concrete resistance to abrasion and wear
Increased if the concrete mix contains well-graded strong aggregate
Methods of Concrete Placement
Cast in Place, Sprayed, Mixed in Place
Process of Hydration
Cement and Water mixture results in hardening
Types of Aggregate for Concrete
Sand, Gravel, Crushed Stone
Selection of Aggregate for Concrete
Resistance to abrasion, Performance, Resistance to effects of freezing/chemicals, Range of Aggregates
Admixtures
Workability, Reduce Moisture, Increase durability, Resistance to Freezing, Accelerate or retard hardening or setting, Increase Flowability
Water Quality for Concrete
Potable Water (Uncontaminated)
2 Styles of Mixing Concrete
Ready-mix and On-site Mixing
Slump Test
Determines Relative Consistency & Reflects changes in the amount of water in the mix
Air Content Test
Determines the air entertainment at the time of use
Cylinder Test
Determines the compressive strength of cured concrete