Masonry basics

Question 1

What type of material is masonry?

Answer 1

Composite - Bricks + Mortar

Question 2

Masonry is a brittle material, but where is the weakness?

Answer 2

Mortar joints

Question 3

How does masonry cope with tension vs compression?

Answer 3

Strong in compression
Weak in tension

Question 4

What do masonry properties depend on?

Answer 4

Masonry is anisotropic
Properties depend on joint orientation
Varies failure modes

Question 5

How strong is masonry and what happens when mortar strength increases?

Answer 5

Between mortar and unit strength
If mortar strength increases, brick strength increases

Question 6

Is masonry elastic or non-linear?

Answer 6

Low stress, masonry is elastic F=kx
If cracks for, highly non-linear and redistribution of load throughout uncracked material

Question 7

What can happen if you restrain masonry?

Answer 7

As brittle material, cracks form

Question 8

What causes vertical cracks?

Answer 8

Flexure and tension

Question 9

What causes horizontal cracks?

Answer 9

Shear and bending

Question 10

What are benefits of masonry?

Answer 10

Versatile
Constructability is high
High performance
Durable
Energy efficient
Acoustic
Qualified labour

Question 11

Describe the brick making process?

Answer 11

1. Crush into powder
2. Mix with water
3. Dry
4. Fire in kiln

Question 12

What are the two types of unit shape?

Answer 12

Solid bricks
Frogged bricks

Question 13

What are units typically constructed of and do they shrink or expand?

Answer 13

Clay or concrete
Clay expands
Concrete shrinks

Question 14

What are the three types of masonry joints?

Answer 14

Question 15

What is a course?

Answer 15

Question 16

What is a stretcher course?

Answer 16

Question 17

What is a header course?

Answer 17

Question 18

What is a soldier course?

Answer 18

Question 19

What is bonding?

Answer 19

Overlapping between courses to distribute load and provide stability

Question 20

What is a stretcher bond?

Answer 20

Question 21

What is a heading bond?

Answer 21

Question 22

What is a flemish bond?

Answer 22

Question 23

What is a stack bond?

Answer 23

Question 24

What is a English bond?

Answer 24

Question 25

What causes variability in masonry units?

Answer 25

Temp bricks are fired: High temp increases strength
Stone inclusions increase strength
Ageing

Question 26

What causes variability of mortar joints?

Answer 26

Composition and quality
Interaction of mortar with adjacent units
Orientation of mortar joints
Ageing

Question 27

How do you cure mortar optimally?

Answer 27

It doesn’t need heat to dry!
Moisture evaporates
Slower this process happens the stronger mortar is

Question 28

What are the joint failure mechanisms?

Answer 28

Question 29

What are unit failure mechanisms?

Answer 29

Question 30

What are the combined failure mechanisms?

Answer 30

Question 31

What are three failure mechanisms of masonry walls?

Answer 31

1. Bed joint sliding
2. Rocking (toe compression failure)
3. Diagonal cracking

Question 32

What is the solution to stresses exerted on walls?

Answer 32

Infill masonry (non-loadbearing wall)

Question 33

What is the solution to vertical and horizontal eccentric loads?

Answer 33

Loadbearing walls thicker

Question 34

What is the solution to buckling?

Answer 34

Thin walls with buttresses

Question 35

What is the solution to uniform pressure of the wind?

Answer 35

Thin walls with ringbeam

Question 36

What is the solution to concentrated pressure of earthquakes?

Answer 36

Reinforced masonry