Masonry Flashcards
How many ways are there to mix mortar and what are they
Portland cement, masonry cement
What are the ingredients of mortar
Portland cement, lime, sand, water
What is a different set of ingredients of mortar
Masonry cement, sand, water
How many types of mortar are there and what are they
M, S, N, O
How many ways can you physically mix mortar
Machine mixing, hand mixing
What is the minimum machine mixing time for mortar
3 minutes
How long do you allow dry ingredients to mix in mixer before adding water
One minute
What are the three types of sand
Manufactured, natural, stand
What are the desirable properties of mortar
Plasticity, water retention, strength and durability
What are the three kinds of levels
Plum, Level, Square
What does it mean to be “plum”
Vertical on two planes
What does it mean to be level
Horizontally straight
What does it mean to be square
90 degrees on all corners
True or False: A foundation must be Square AND Level AND Plum
True
True/False: A Cinder block may be load bearing
False
True/False: A Concrete block (or a Concrete Masonry Unit (CMU)) may be load bearing
True
What are the 5 parts of a wall
Corner/end Field Control/expansion joints Wall intersections Rough opening (doors/windows)
What is the definition of masonry construction
To build a structure from any building materials that consist of units held together with mortar; concrete block, brick, stones, clay tile and sometimes even glass block .
What factors effect the bond strength of mortar
Type and quality of mortar M,S,N,O • Workability or plasticity • Water retentivity • Surface texture of the mortar bed • Quality of workmanship in laying the units.
What are the two ways to mix mortar
Portland Cement
Masonry Cement
Type M motar
Used for below-grade masonry that contacts earth (i.e. foundations, retaining walls, walkways)
1 part portland cement
1/4 part hydrated lime or lime putty 3 parts sand
OR
1 part portland cement
1 part Type II masonry cement 6 parts sand
Type S Mortar
Used where high resistance to lateral forces are required.
1 part portland cement
1/2 part hydrated lime or lime putty 4 1/2 parts sand
OR
1/2 part portland cement
1 part hydrated lime or lime putty 4 1/2 parts sand
Type N mortar
Used in above-grade and exposed masonry where high compressive and/or lateral strengths are not require.
1 part portland cement
1 part hydrated lime or lime putty 6 parts sand
OR
1 part Type II masonry cement
3 parts sand
Type O
Used for load-bearing, solid-unit walls when the
compressive stresses do not
exceed 100 psi, and the subject to freezing and thawing in the
masonry is not
presence of a lot of water.
1 part portland cement
2 parts hydrated lime or lime putty 9 parts sand
OR
1 part Type I or Type II masonry cement 3 parts sand
Calcium chloride cannot be more than what percent by weight of your mortar (when used as accelerant)
2%
When should Calcium chloride not be used
For steel- reinforced masonry (i.e. reinforced concrete)
What two mortar materials should be covered to prevent moisture loss
Sand and Lime
How wide does the footing have to be
2x wall thickness
How do you lay the first course
Locate the corners. Lay mortar bed. Lay blocks on corners first, then work inward toward the middle. Ensure all block is level and plumb. Ensure all mortar joints are filled and tooled.
Describe laying corners
Build up the corners 4 or 5 courses high.
Step each course back one-half block.
Mortar for horizontal joints is applied to the
top of the course previously laid.
Apply mortar for the vertical joints to either the block being laid or to the block previously laid.
When do you tool the joints
Once the mortar becomes
“Thumbprint” hard.
In what order do you strike the joint
Vertical first, then horizontal
What are the two types of lintels
- Precast from concrete.
* Constructed from lintel block,steel reinforcement bar, and concrete.
Equation: Estimate number of masonry blocks
Linear Feet x Height x 1.125 = Total number block
Equation: Estimate masonry cement in block build
Total Block / 100 x 3 = Bags of masonry cement
Equation: Estimate sand in masonry build
1 Ton of sand per every 8 bags of masonry cement; Therefore, divide number of bags by 8
Equation: Number of gallons of water per bag of masonry cement
Water = 8 gl per bag
Equation: Number of bricks in masonry build
Linear Foot x Height x 6.75 = number of Bricks
Equation: Estimate masonry cement in brick build
Total Bricks / 1000 x 8 = Masonry bags
Equation: Estimate sand in masonry brick build
1 Ton of sand per 1,000 bricks; Therefore, divide number of bricks by 1,000
What is the max length a wall can be without an expansion joint
25 feet
