Pile_Foundation Flashcards
A branch line feeds a fire hose 45’ from the riser, what’s its size?
1.25”
According to the code, steam pipe which must be buried by tunneling, the trench may be no longer than _________ when the trench is 14’ deep.
7
According to code, plates or sills shall be anchored to concrete foundation walls with bolts spaced not more than how far apart?
72”
According to code, what is the minimum thickness permitted for a concrete slab that is supported directly on the ground?
3 1/2”
A slab has just been placed and finished. It is normal concrete. According to code, unless accelerated curing methods are used, the slab must be cured in a moist condition for at least:
7 days
After one season, a concrete slab shows crazing and dusting and spalling. These defects were caused by:
Working the surface while bleed water was present
What should be done when the excavation for a footing is dug too deep in some places?
The excavation should be dug out so that the bottom is level and a thicker footing poured
Steel embedded in concrete almost always becomes:
Cathode
Horizontal members on the outside of prefabricated forms used to straighten and align forms are called
Walers
Piles are specified for a bridge. What action drives a single acting pile driver?
They fall by gravity
A contractor cannot place backfill material against a concrete structure wall until the concrete has developed a compressive strength of _____ PSI
3000
What is a Jackshore?
A single all metal adjustable post
Concrete consistency is determined by
Slump
Segregation in concrete walls is caused by:
Excessive water to cement ratio
According to design and control of concrete mixtures, water tightness in concrete is best achieved by which of the following
Low cement to water ratio
What is the main purpose for installing a sub-surface dewatering system
Lower water table
In what soil will a well-point dewatering system be most effective?
Sand
When is sheet piling installed in areas with a high water table
Before excavation
Concrete used in public works flood control and drainage systems must be air-entrained within what percentage range?
4%-7%
If the subgrade is damp prior to placing a concrete slab during hot dry weather, it will
Prevent the subgrade from drawing too much water from the concrete
Difference between piers and pilasters used in masonry construction?
Piers are isolated and freestanding whereas pilasters are built into a wall thickening a small wall section
When joints to control cracking in concrete slabs are cut, they should be cut to a depth of:
1/4 the slab thickness
What are all the tests that may be required in the project specs for concrete quality control?
Strength, slump, air
When super plasticizers are used in a concrete mix:
Less water will be needed for the same workability
Which factor does not affect the lateral pressure of plastic concrete form wall?
Use of air-entrained mixture
A failed concrete slab contains a construction joint. What is used to continue a construction joint through a concrete patch repair?
Permanent bond breaker
Concrete curing procedures for a new slab should begin immediately after:
Finishing is complete
After one season, a concrete slab shows crazing and dusting and spalling. These defects were caused during finishing by:
Overworking the concrete surface
A concrete slab is to be poured during hot dry weather. What is the result when the subgrade is moistened with water just before pouring the slab?
There will be an increase in the water to cement ratio, which reduces concrete strength
If concrete weighs 150 pounds per cubic foot, it will place a load on the forms of _______ pounds per square foot for each inch of slab thickness
10
To what depth are concrete control joints raked?
1/2”
Material that must be removed from reinforcing steel before placement
Dry mortar
Concrete blocks piers are being used to support a manufactured home. The cells must be reenforced with concrete and steel if the height of the piers exceeds a minimum of
48”
What are the minimum acceptable dimensions for a wood cap on a pier that is 42” high?
2x8x16
What is the minimum acceptable thickness for a masonry pier cap?
4”
Piers shall be spaced a maximum of how many feet on center?
8’
What is the minimum length of time that a concrete slab, beam, or footing (other than high early), must cure to achieve 70% of its design strength?
7 days
Purpose of bull floating a freshly placed slab is to
Embed large aggregates and level the surface
Troweling of a fresh concrete is performed following the _______ of the slab
Floating
Air entrainment of concrete is to
Improve the freeze thaw resistance
How many layers of concrete are in a slump test?
3
What type of pile has the most friction
Wood
What is a pile driven on an angle called?
Battered
A _________ is used to perform a slump test
Cone
Reinforcing steel in a slab is used for ________ strength
Tensile (flexural)
Under ASTM standards, an engineered design mix for freshly batch concrete, (other than type III cement) would require _________ days for full field curing time.
28
What do you use to increase compression strength in concrete?
Vibration
A ____ is used for a test to measure compression strength in concrete
Cylinder
A reinforcing bar is protruding from a slab with the #5 stamped on it. This means that the diameter of the bar is ______ inches
.625
What is the time for a moisture cure on a slab
7 days
Duplex nails are used for
Forming
As concrete sets, it releases hear known as:
Heat of hydration
What is not a factor when working with concrete?
Resistance
How far does a control joint enter the slab?
1/4 the depth
A part of a concrete wall that gives lateral support is called
Buttress
Not a standard deformed rebar size?
15
Concrete has been placed and will not be subject to accelerated curing. What is the minimum temperature the concrete must be maintained at during curing?
50°
In multi story slab form work, where should shores be located relative to those on the level below?
Directly above
At the absence of the engineered specified strength, what is a guideline for the removal of wall and column forms?
48 hours
Which of the following types of pan is used to form a two-way waffle slab?
Dome
Anchor bolts are to be used to connect a plat to a concrete slab. The minimum spacing of the bolts will be _______
24”
What is the minimum compaction that is required for soil under a concrete slab?
90%
Specs for readymixed concrete conforming to ASTM C94 standards require that the discharge of concrete be completed within 1 1/2 hours or ______ drum revolutions
300
Concrete is to pumped into place using a concrete pump. How must the concrete pumping operation occur?
It should be continuous
How far apart should control joints be spaced in a 6” slab?
15’
Which of the following is used to measure the consistency and workability of concrete?
Slump
All concrete that will be exposed to freeze/thaw conditions should:
Be air entrained
Which of the following types of Portland cement is used in massive concrete structures where low heat of hydration is required
IV
Structural concrete slabs, columns, and other members should be protected to ________ percent of their design strength
70%
In comparing normal concrete to high early concrete (Type III), how much do you reduce the curing time for high early?
4 days
What type of hammer drives piles the fastest?
Vibratory
A pile that is driven into the ground and leaves the shell or casing in is called what?
Shell
What powers a single action pile driver?
Gravity
Aggregate particles used for concrete should be shaped like?
Cubes
The purpose of adding wire mesh to concrete is to
Increase the flexural strength
When pouring concrete on a hot day, what would you not do?
Make sure the forms are dry
Under a slab, what would be the best soil?
Undisturbed or existing soil
If you saw cut a slab, what type of joint will you create?
Control
Compared to wood poles, concrete poles have the advantage of _________
Availability
Concrete curing procedures and curing compounds should be applied:
After final finishing, as soon as the concrete surface is dry
In slip firm construction, to insure proper placement of the concrete:
Low slump concrete is required
What type of foundation covers an entire site and consists of heavily reinforced concrete that is 3 feet to 8 feet in thickness
Mat
When compacting a base for concrete or other soil materials which require compacting, compaction by a vibratory roller is most effective on materials that are primarily
Sand or gravel
Lateral rebar placed in a one way concrete slab to allow for movement due to changes in temperature is called
Temperature steel
The placing of concrete on frozen soil is
Never acceptable
The volume of one 94 pound bag of Portland cement is _______ cubic foot/feet
1
If the specs call for a 40 bar diameter lap on rebar, the length of lap or splice on a #4 bar is
1’ 8”
According to code, reinforcing steel which is cast against and permanently exposed to earth must have a minimum cover of at least ______ inches
3
For the same workability, for air entrained concrete you should
Decrease the water
What would be used to seal out or cancel water from penetrating through a concrete joint?
Water stop
Manually controlled powered concrete trowels shall be equipped with a
Hand release shut off or kill switch
A number 6 reinforcing bar that is not exposed to the soil or weather must have a minimum concrete cover of at least
3/4”
How much should you decrease the water if you have air entrained concrete with 1-1/2” aggregate and a 2” slump
20%
How many tests for strength of concrete should be performed for a pour of 750 cubic yards
5
What causes cracks in concrete during hot weather?
Rapid drying of top
Defined as a groove (formed or saw-cut) in the concrete placed where the shrinkage of the concrete would cause a crack.
Control joint
In the normal concrete finishing process, __________ is performed prior to bull floating.
Screeding
Super-plasticizers used in concrete will cause:
A decrease in the amount of water needed to provide workability
Concrete application with forms, wire cages, and plastic is called
Inpinged
Concrete strength depends on a correct water/cement ratio. Water used for concrete mixing must be metered and discharged within all acceptable tolerance limits of _____ %
5
Portland cement concrete pavement must achieve a minimum compressive strength of 3850 psi within how many days of placement?
28
What is the minimum finish grade slope for the land around a foundation?
The finish grade must slope sufficiently to drain water away from the foundation
What is the most likely result of rapid moisture loss from a concrete slab after the concrete is placed?
Dusting
When using wire mesh in a concrete slab placed directly on the earth, place the mesh in minimum of ______ inches down from the surface
1 1/2
The main purpose of using an isolation joint in concrete slabs is to:
Separate between concrete pours
A common admixture that causes concrete to set up faster is ________
Calcium chloride
Regarding a masonry pier, as a general rule of thumb, the maximum height of the pier is ______ times the least dimensional width of its base
10
What is the reccomend type of Portland cement to be used in concrete which is exposed to severe sulfate conditions?
V
In a slab, the maximum size of the aggregate shall not exceed ________ the thickness of the slab
1/3
The depth of a foundation footing is determined by
Frost depth
Adding water to concrete that is already workable will decrease the concretes
Strength
What type of pile is enlarged on the ends in order to provide a larger bearing area?
Bell pile
A wall that is poured as part of the foundation is what?
Monolith
What is the minimum temperature of concrete when the ambient temperature is 35 F?
40
