CM 225 MASONRY FINAL EXAM 2023 QUESTIONS
AND ANSWERS
Concrete masonry units are manufactured using high slump concrete
False
____, ____, and ____ describe the relative smoothness or graininess of the
masonry unit texture
Fine, medium, coarse
What is the typical size of concrete block, also called concrete masonry units
(CMU)?
8x8x16
In the US, concrete masonry units are manufactured to conform to requirements
of the
American Society for Testing and Materials
Using locally available sands, cements, and coarse aggregates to produce
concrete block of desired color is recommended because
It will result in a more easily duplicated color in the event of future additions to the
structure
The hollow core of masonry units are often flared on the face of the web to
Provide a broader base for mortar bedding
Provide better gripping for the masons
Modular masonry units are based on a module size and are reduced by the
thickness of a standard mortar joint which is:
3/8%
Hollow and solid load-bearing block with ASTM designation C90 have a minimum
comprehensive strength in psi of a single unit of:
1700 PSI
Block dimensions are commonly referred to in this order.
WxHxL
Normal weight and light weight masonry units derive their name from the density
of the
Aggregates
Grout in masonry construction
Acts compositely with reinforcement to resist implied loads
The most important quality of a masonry mortar is
Workability
Grouting of brick or block serves the following purposes
It bonds the wythes together in multi wythe wall construction
It transfers stresses from the masonry to the reinforcing steel when a wall is subjected
to lateral forces
It increases the cross-sectional area of the wall and aids in resisting vertical loads and
lateral shear loads
Mortar in masonry construction
Creates a tight seal between units against the entry of air and moisture
Bonds with joint reinforcement metal ties, and anchor bolts
, Compensates for slight size variations in the units
Provides an architectural quality to exposed masonry structures
It is acceptable to retemper mortar by adding water and further mixing
True
After all materials for the mortar have been batched, they should be mixed for
3-5 minutes
Efflorescence is caused by
Soluble salts that have emerged from below the surface
Mortar and grout can be used interchangeably
False
Mortar should be used within ___ hours after mixing
2.5
The recommended type of mortar for exterior elements that are at or below grade
is
Type S
A 10 inch cavity wall consisting of concrete brick, 4" hollow concrete block and
5/8" plaster has a total R value of
4.05
An 8" thick fully grouted masonry wall can support how many feet in depth of
unbalanced backfill?
7'
The structural beam above a window or door opening in a masonry wall that
carries the wall load above is a:
Lintel
Allowable concentric axial load on an unreinforced laterally supported concrete
masonry wall depends on which three features
Wall height
Wall thickness
Masonry Compressive Strength
A 10" cavity wall consisting of 4" brick, 4" lightweight hollow units and plastered
with ½" gypsum plaster has a sound transmission loss of
57
Modern concrete masonry wall construction is of what two general types?
plain
Reinforced
The two methods used to determine masonry strength for a particular mortar type
and masonry unit are:
Unit Strength Method
Prism Test Method
Lighter weight aggregate masonry units have a greater fire endurance than one
constructed of normal weight aggregate
True
An 8" thick, unreinforced, hollow unit concrete masonry wall subjected to a 20 psf
wind load and a 4.00 kip/ft concentric axial load has a maximum wall height in
feet of:
20.35
AND ANSWERS
Concrete masonry units are manufactured using high slump concrete
False
____, ____, and ____ describe the relative smoothness or graininess of the
masonry unit texture
Fine, medium, coarse
What is the typical size of concrete block, also called concrete masonry units
(CMU)?
8x8x16
In the US, concrete masonry units are manufactured to conform to requirements
of the
American Society for Testing and Materials
Using locally available sands, cements, and coarse aggregates to produce
concrete block of desired color is recommended because
It will result in a more easily duplicated color in the event of future additions to the
structure
The hollow core of masonry units are often flared on the face of the web to
Provide a broader base for mortar bedding
Provide better gripping for the masons
Modular masonry units are based on a module size and are reduced by the
thickness of a standard mortar joint which is:
3/8%
Hollow and solid load-bearing block with ASTM designation C90 have a minimum
comprehensive strength in psi of a single unit of:
1700 PSI
Block dimensions are commonly referred to in this order.
WxHxL
Normal weight and light weight masonry units derive their name from the density
of the
Aggregates
Grout in masonry construction
Acts compositely with reinforcement to resist implied loads
The most important quality of a masonry mortar is
Workability
Grouting of brick or block serves the following purposes
It bonds the wythes together in multi wythe wall construction
It transfers stresses from the masonry to the reinforcing steel when a wall is subjected
to lateral forces
It increases the cross-sectional area of the wall and aids in resisting vertical loads and
lateral shear loads
Mortar in masonry construction
Creates a tight seal between units against the entry of air and moisture
Bonds with joint reinforcement metal ties, and anchor bolts
, Compensates for slight size variations in the units
Provides an architectural quality to exposed masonry structures
It is acceptable to retemper mortar by adding water and further mixing
True
After all materials for the mortar have been batched, they should be mixed for
3-5 minutes
Efflorescence is caused by
Soluble salts that have emerged from below the surface
Mortar and grout can be used interchangeably
False
Mortar should be used within ___ hours after mixing
2.5
The recommended type of mortar for exterior elements that are at or below grade
is
Type S
A 10 inch cavity wall consisting of concrete brick, 4" hollow concrete block and
5/8" plaster has a total R value of
4.05
An 8" thick fully grouted masonry wall can support how many feet in depth of
unbalanced backfill?
7'
The structural beam above a window or door opening in a masonry wall that
carries the wall load above is a:
Lintel
Allowable concentric axial load on an unreinforced laterally supported concrete
masonry wall depends on which three features
Wall height
Wall thickness
Masonry Compressive Strength
A 10" cavity wall consisting of 4" brick, 4" lightweight hollow units and plastered
with ½" gypsum plaster has a sound transmission loss of
57
Modern concrete masonry wall construction is of what two general types?
plain
Reinforced
The two methods used to determine masonry strength for a particular mortar type
and masonry unit are:
Unit Strength Method
Prism Test Method
Lighter weight aggregate masonry units have a greater fire endurance than one
constructed of normal weight aggregate
True
An 8" thick, unreinforced, hollow unit concrete masonry wall subjected to a 20 psf
wind load and a 4.00 kip/ft concentric axial load has a maximum wall height in
feet of:
20.35
