07 Reinforced Concrete Construction Flashcards
(31 cards)
Any concrete which is transported through a hose or pipe by means of pump.
Pumped Concrete (Pumpcrete)
Concrete production system which is delivered to the job site ready for placement.
Ready Mix
The process of providing gentle motion in mixed concrete, just sufficient to prevent segregation of materials and loss of plasticity.
Agitation
Any substance other than cement, water, or aggregate added to a concrete or mortar mix to alter its properties or those of the hardened product, also called additives.
Admixture
An admixture that disperses entrained air to increase workability, and improve resistance to cracking.
Air Entraining Agent
An admixture that hastens the setting and strength development of a concrete, mortar, or plaster mix.
Accelerator
An admixture that slows the setting of concrete, mortar, or plaster mix in order to allow more time for placing and working the mix.
Retarder / Decelerator
An admixture used for reducing tension of the mixing water in a concrete mix thereby facilitating the wetting and penetrating action of water.
Surface-Active Agent
An admixture that reduces the amount of mixing water required for the desired workability. Lowering the water-cement ratio generally results in increased strength.
Water Reducing Agent / Superplasticizer
An admixture of a pigment or dye is added to a concrete mix to alter or control its color.
Coloring Agent
An admixture causing cement particles to separate by imparting like electrostatic charges, it prevents bleeding of water to the surface of the concrete.
Dispersal Agent
An admixture that increases denseness of concrete surfaces which are subjected to rolling live loads and impact.
Concrete Hardener
An admixture that renders concrete more impermeable.
Concrete Wateproof
An admixture that improves bond between two concrete surfaces.
Bonding Agent
An admixture that prevents cement paste from bonding to the surface and inhibits the setting of cement paste.
Set Inhibiting Agent
An admixture that prevents the evaporation of water from concrete and allows it to be retained for hydration.
Surface Sealing Agent
An admixture that causes a slight expansion in plastic concrete or mortar and thus reducing or eliminating voids caused by settlement.
Gas Forming Agent
An admixture of abrasive material is used as topping to prevent slippery surfaces.
Non-skid Surface Agent
An admixture that is sometimes used in structures where it is desirable to avoid high temperature or in structures exposed to seawater or water containing sulfates.
Pozzolanic Admixture
Any of various hard, inert materials such as sand and gravel added to cement to make concrete or mortar.
Aggregate
Consisting of sand having a particle size smaller than 1/4” (6.4 mm) and shall pass through a 3/8” (9.5 mm) sieve.
Fine Aggregate
Consists of crushed stones, gravel, or blast furnace slag having a particle size larger than 1/4” (6.4 m). Specify the portion of aggregate that is retained on a No.4 (4.8 mm) sieve.
Course Aggregate
A joint between adjacent parts of a building that permits their relative movement due to temperature changes.
Expansion Joint / Contraction Joint
A joint where two successive placements of concrete meet.
Construction Joint
