Masonry Flashcards
formula for estimating masonry block
linear feet x height x 1.125 =Total # of blocks
formula estimating masonry cement…
(number of blocks ÷ 100) x 3 = bags of cement
formula estimating for masonry sand
1 ton of sand per 8 bags of masonry cement
-or-
bags of cement ÷ 8 = tons of sand
formula estimating for water
8 gallons of water per bag of cement
-or-
bags of cement x8 =gallons of water
how many CMU blocks come on a pallet?
94
formula for concrete Project Volume
PV= L ×W ×H × #of pads
formula calculating concrete Loss Factor
LF = PV x 1.1 (if under 5400 cubic ft/200cu yd)
LF = PV x1.05 (if over 5400cu ft/200cu yd
formula calculating concrete Loss Volume?
LV= LF x1.5
what are the most common types of mortar mixes?
N M S O
formula calculating cement, sand, and gravel for concrete
1/6 x LV =bags of cement
2/6 x LV = cubic feet of sand
3/6 x LV = cubic feet of gravel
How much concrete can delivery trucks hold?
10 cubic yards
formula converting cubic feet into cubic yards
(length x width x height) ÷ 27 = cubic yards
how much time do you have to pour concrete, once water is mixed in?
3 hours
What are the benefits of a lower psi mortar?
better adhesive and sealing powers
What is the most common cement used by the military?
Portland Cement
what type of mortar is general purpose?
Type N
What is Type N mortar used for?
above grade work, interior and exterior load bearing
What type of mortar has the highest compressive strength and is used for below grade load bearing?
Type M
What is Type S mortar used for?
below grade, sewers, brick patio/driveway
What type of mortar is used for above grade, non-load bearing situations?
Type O
What type of mortar is used for historic preservation?
Type K
Formula for Volume of a cylinder
V= pi x Radius squared x height
When hand mixing what order should you mix?
dry goods mixed, then add water
What components go into concrete?
Portland cement, water, aggregates
what affect does water have in mixing concrete?
less water makes a stronger mix
Concrete should be mixed with 60-80% of what?
Aggregates
What is used primarily to gain economy, in concrete mixtures?
Aggregates
what are the types of Aggregates in a concrete mix?
Course- gravel, rock
Fine- sand
What are the types of Portland Cement?
Type 1 Normal, Type 2 modified, Type 3 high early, Type 4 low heat Type 5 sulfate resistant
what types of Portland Cement are “air entrained”?
Types 1,2,3
What are the types of concrete?
Reinforced, pre-stressed, Precast, lightweight
Which type of concrete is easier to ship and fire resistant?
lightweight
Describe pre-stressed concrete
reinforced rebar or welded wires are stretched with tension before concrete is poured over it
what type of concrete has steel rods running through it?
Reinforced
What are the disadvantages of concrete?
Weak tinsel strength, expansion and contraction, shrinks while drying, weight
what advantages does concrete have over other materials?
durability, castable, economical, compressive strength
What type of joint controls cracking?
control joint
where would an expansion joint be located? What would it consist of?
between two slabs of concrete, such as sidewalk and building, or driveway and sidewalk.
a resilient material, rubber, wood etc no more than 1/4in thick
what must concrete forms be?
tight rigid strong
what must be <4ft per hour, vertically?
rate of filling concrete
When should you never pour concrete?
freezing Temps
when should you use accelerators?
When pouring in Temps over 90 degrees
when should you not use accelerators? why?
in reinforced concrete. they are oxidize and will weaken the metal
What is it called when you add more water to concrete mix?
retempering
what is Modular Construction?
when the dimensions of the construction are made around the size of block being used
Name the parts of a wall
corner/end, field, expansion/control Joint, intersection
what do you put in a block wall, every 4ft?
rebar reinforcement
What are the 3 essential things the foundation must be?
plumb, level, square
what does plumb mean?
perpendicular, straight up and down, on 2 axis’
what does it mean to be even on a horizontal plane?
level
what does square mean?
equal distances and angles
what are some considerations of a job site?
drainage, slope, soil stability, tactical employment, commanders desire
what size should footing be?
2x wall thickness
