Materials Flashcards
Name three things that can help create a strong concrete beam
- install rebar or fiber reinforcement
- Include fly ash as an admixture along with cement, fine and coarse aggregates
- Using high strength cement
When compared to a low water-to-cement ratio concrete, a high water-to-cement ratio concrete is?
weaker, as water to cement ratio increases, strength decreases
what is RQD
percentage of toatl core run length consisting of pieces greater than 4 inches,
what type of cement should be specified for the batch mix-design for a project that has a high sulfate resistance
type V type 5
what test methods can be used to identify potential internal defects
Impact-echo, ultrasonic echo and Impulse response
how does increasing water - cement ratio affect slump?
increased slump, when wc increases the workability(slump).
not all water is consumed during the cemener hydration, the final concrete product will have a high porosity
how does increasing water - cement ratio affect porosity of concrete product?
not all water is consumed during the cemener hydration, the final concrete product will have a high porosity
how does concrete porosity affect the strength of the concrete
more porosity produces less strong concrete
what impact does water-cement ratio have on air content?
No impact
what is the swell factor?
loose unit weight divided by the bank unit weight
How does water - to cement ratio affect permability?
High water to cement ratio is more permeable
How does high water to cement ratio affect shrinkage?
more water more shrinkage
For a Concrete mix problem about yeild of concrete in ft^3, how many pounds do you account for Air
Zero, do not add weight for air
With Casgrande’s cup method, how is liquid limit defined
it is defined as the water content as which the grove cut into the soil will close over a distance of 12.5 mm following 25 blows
what soil has the greatest volume, loose soil , compacted or bank soil?
loose soil l has the greatest volume
what soil has the smallest volume, loose soil , compacted or bank soil?
Compacted
what is the equation for Compacted Cubic yard or CCY?
CCY = BCY(bank cubic yard) X shrinkage factor
Deformation of soil are a function of?
Effective stress, total stresses, pore water pressure
Based on the principal of effective stress, effective stress equals total stress minus pore water pressure. IT is the ,post important principal in soil mechanics
What is swell factor?
is the loose unit weight divided by the bank unit weight
Name two geosynthetics used for soil stabilization?
Geotextiles and GEogrids
Name two geosynthetics used for soil stabilization?
Geotextiles and Geogrids
what are Geonets used for?
drainage purposes
what are Geomembranes used for?
as a liner or a barrier to control fluid penetration
What should a concrete mix consist of if it needs to be 3,500 psi, completed duting and 8 -hour window at night, where temperated are average 50 Degrees F
an early strength concrete, Type III cement and chemical accelerators
what is type I Cement
what is type II Cement
what is type III cement?
what is type IV cement?
what is type V cement?
sulfate-resistant
Fatigue in steel can be the result of ?
a reduction in strength due to cyclical loads
what is Sheet erosion
What is Rill Erosion
What is Gully erosion
summarize the 5 types of cement
ordinary (Type I),
modified (Type II),
high-early-strength (Type III),
low-heat (Type IV), and
sulfate-resistant (Type V)
what is type 2 cement and when should it be used
this is the modified version of type1 when is between 1 and the sulfate resistance type V
- where soil contains only moderate amounts of sulfade
- roadways and transportation
what is type 3 cement and when should it be used
this is the early strength concrete
perfect for cold weather ( that affects how quickly concrete cures) also when quick turn a around is needed
what is type 4 cement and when should it be used
Type IV cement generates less heat during hydration and curing than ordinary Type I portland cement.
When conducting mass pours or casting large-volume concrete products, Type IV cement is often used to lessen the amount of heat generated and reduce the risk of flash setting or thermal shock.
Type IV cement’s ability to generate less heat during hydration is also beneficial in hot weather concreting applications where fresh concrete may cure at an expedited rate due to high ambient temperatures.
what is type 5 cement and when should it be used
Type V cement is used in concrete products where extreme sulfate resistance is necessary. Coastal structures, piers, underwater tunnels, submerged structures, foundations, roadways and transportation products are all common applications for Type V cement.
