Masonry Flashcards
How should you take care of your tool while doing masonry work?
- Wet tools before use
2. Rinse all tools with water frequently
What are the dimension (nominal and actual) of a CMU/Cinder block?
8816 (7 5/87 5/815 5/8)
What are the size of a masonry joints?
3/8
What is the weight range of a CMU block?
35-45 LBS
What is the weight range of a cinder block?
25-35 LBS
What is the difference between a cinder block and a CMU block?
CMU blocks are used for load bearing wall while cinder block are used for non-bearing wall
What are the different factors affecting bond strength to take into account in the choice of a mortar?
Type
Quality
Workability
Water retention
What are the desirable properties of a mortar?
Plasticity
Water retention
Strength
Duarbility
What are the two different kind of cement used?
Masonry
Portland
What are the different types of mortar?
M Below grade; contact with Earth 2500 psi
S High resistance to lateral forces 1800 psi
O Above grade non-load bearing 350 psi
N Above grade; high or lateral strength not required 750 psi
K Solely for historic preservation 75 psi
What are the two types of mixing?
Machine
Hand
What is the mixing time for a machine?
3 MIN; 1ST MIN dry
How do we want the sand to be and what are the two categories of sand?
Damp and loose
Manufactured and Natural
What are the steps of first course?
- Locate the corners
- Lay mortar bed
- Lay block on all corners first
- Insure all blocks are leveled and plumb
- Insure all mortar joints are filled
- Laying block between corners (Line block+mason twine)
- Closure block
- Reinforce
- Control joints
What size of a gap should you leave for the closure block?
Leave a 16 1/2 space
What type of wood should you use when in contact with masonry?
Pressure treated
Isolate with moisture barrier to prevent moisture loss
Should you interlock course between load bearing and non-bearing walls?
No
What are the two types of lintel?
Constructed
Precast
What are two type of finishing action?
Tooling/Striking
Patching
How should you be striking?
Vertical then horizontal
What is the rule of thumb for the placement of control joints?
No more than 25 feet between the joints
No thicker than 1/2 inch
What are the two types of finishing joints?
Concave joint
V-joint
How many bricks make a pallet?
525 Bricks
How many CMU blocks make a pallet?
94 CMU Block
What is the difference between hydrated lime and lime putty?
Lime putty is wet hydrate lime (you add some water to it and stir it up)
What are the two types of lime hydrate?
Type S (Special) - Dolomitic limestone 33-50% Mg carbonate Type N (Normal) - High calcium limestone less than 5% Mg carbonate
What type of lime hydrate is the one normally used?
Type S lime hydrate
What are the typical hollow block size?
4’’, 6’’, 8’’, 10’’ and 12’’
Can you use calcium chloride when working with steel reinforced masonry?
No
What should be the distance between anchor bolt?
4 ft
When tie walls together what is thew distance between metal ties?
4 ft vertically
What is the purpose of tooling?
Watertight and looks good
