Reviewer 6 Flashcards
(127 cards)
What materials have adhesive and cohesive properties necessary to bond inert aggregates into a solid mass o adequate strength and durability
Admixtures Adhering Materials Inorganic Materials Cementitious Materials None of the Above
Cementitious Materials
What is generated when compounds in cement react with water to acquire stable low energy states?
Heat of Hydration
What compound reduce the interparticle forces that exist between cement grains in the fresh paste; thereby increasing the paste fluidity
Plasticizers
In mixes exposed to water, what is the term used to refer to the separation of aggregate from the bitumen due to the faster absorption of water on the aggregate surface?
Slippage
A parameter used for estimating strength of concrete
Water cement ratio
It is the property of fresh concrete which is the ability to flow under momentum transfer or under mechanical stress
Mobility
Placeability
True or False. As water to cement ratio increases, there is progressive weakening due to increase in porosity.
True
It is a temporary dam-like structure constructed around an excavation to exclude water
Cofferdam
Which of the following is not a property of hardened hydraulic cement concrete
Workability
Which of the following properties of aggregates has the least influence tp the quality of concrete?
Color, texture, and shape of its aggregates
Which of the following will minimize the cracking of pavement due to thermal expansion?
Compaction of subgrade
Provide Expansion Joints and sectional pouring of concrete
Consistency of concrete mixed
Provide expansion joints and sectional pouring of concrete
What is the mode of failure for short columns at which the concrete reaches its limits strain Eu at precisely the same instant that the tensile steel on the far side of the column reaches yield strain Ey
Balanced Condition
Given:
Es = 29, 000 ksi
Econcrete = 6, 000 ksi
What is the modular ratio?
4.83
just divide Es / Econcrete
What is the max Vs (shear carried by the stirrups)
2/3 sqrt( f’c)
What is the distance from the extreme fiver in compression to the centroid of the tension steel area
Effective Depth
The maximum usable strain at the extreme concrete compression fiver shall be assumed to be equal to ___
0.003
A burried plate, wall, or block attached at some distance from and forming an anchorage for retaining wall
anchor plate
It is a beam especially provided over an opening for a door, window, etch. to carry the wall over the opening
Lintel beam
What will happen to the concrete strength if the water to cement ratio decreases?
Concrete strength increases, porosity decreases, solid-to-space ratio increases
What is the property of concrete by which it continuous to deform with time under sustained loads at unit stresses within acceptable elastic range?
Creep
Honeycomb structures exhibit
small arches with chain particles
has a void ratio of 0.91 for a simple cubic packing
has a void ratio of 0.35 for pyramidal packing
Negative relative densities
What is the condition where the tension steel strain reaches the yielding strain simultaneously with the concrete reaching the crushing strain which is usually 0.003?
Balanced strain
What is a material that has adhesive and cohesive properties enabling it to bound mineral fragments into a solid mass in the presence of water?
Hydraulic cement
The ability of the soil to allow water to flow through it
Permeability
