masonry 2.04

Question 1

what are the demands of masonry ?

Answer 1

-load transfer
-shell protective function
-thermal and sound insulation
-high fire resistance
-architecture

Question 2

type of fire brick

Answer 2

clay brick

Question 3

type of minerally bound bricks

Answer 3

-lime sand bricks
-light-weight concrete bricks
-concrete bricks
-slag bricks
-aerated concrete bricks

Question 4

brick shapes:

Answer 4

• dunnformat: 240x115x52
  -normalformat: 240x115x71
  -2 dunnformat: 240x115x113
  -12 dunnformat: 240x365x238

Question 5

masonry wall assembly types:

Answer 5

-lauferverband = soga
-blockverband = combinado
-binderverband = tizon
-kreuzverband = combinado

Question 6

influencing factors for compressive strength:

Answer 6

• Compressive and tensile strengths of bricks
• Ratio Young’s modulus of bricks to Young’s modulus of the mortar
• Joint height
• Brick height
• Ratio compressive strength bricks to compressive strength mortar
• Stress direction and eccentricity
• Moisture content of the bricks
• Short- or long-term loading
• Cyclic loading (fatigue failure)
• Quality of workmanship

Question 7

shear load Bond failure

Answer 7

• Low compressive stresses (small on-top load)
• Tensile load in the boundary area by redistribution of stresses

Question 8

shear load Joint failure

Answer 8

Shear stresses exceed the adhesive
shear strength and the friction
resistance in the area of the lower
loaded brick part. Prerequisites:
- low on-top load
- high brick strength.

Question 9

shear load Brick tension failure

Answer 9

• High compressive stress  high friction resistance
• Admission of the shear forces from two layers acting on one brick
• Inclined main tension stresses in the brick
• Cracks in bricks propagating further into butt joints

Question 10

shear load Compression failure of masonry

Answer 10

• very high on-top load
• inclined main tension stresses

Question 11

influencing factors for failure under shear load

Answer 11

• Height of the vertical load
• Bond strength between brick and horizontal joint
• Shear strength between brick and mortar
  (combination of the bond strength and friction resistance)
• Tensile strength of the brick
• Compressive strength of the masonry
• Quality of workmanship
• Kind of masonry assembly