2. Prof. Kurtz, Age 7

3. Prof. Kurtz, Age 7

4. Actual Mortar
Prof. Kurtz, Age 7

5. Real Slate
Actual Mortar
Prof. Kurtz, Age 7

6. Lesson 19: Lateral Load Path in Buildings
Real Slate
Lesson 19: Lateral Load Path in Buildings
Actual Mortar
Prof. Kurtz, Age 7

7. Lesson 19: Lateral Load Path in Buildings

8. Tributary Widths
What is Tributary Width of Typical Interior Fill Beam?
Answer: 5-ft
If the applied pressure is 50 psf, what is distributed load w on Typical Interior Fill Beam?
w = (5’)(50psf) = 250 plf
20’, typ.
30’, typ.
Building Plan View 4 3 2 1 A B C D

9. Tributary Widths
What is Tributary Width of Typical Interior Fill Beam?
Answer: 5-ft
If the applied pressure is 50 psf, what is distributed load w on Typical Interior Fill Beam?
w = (5’)(50psf) = 250 plf
20’, typ.
30’, typ.
Building Plan View 4 3 2 1 A B C D

10. Tributary Widths
What is Tributary Width of Typical Interior Fill Beam?
Answer: 5-ft
If the applied pressure is 50 psf, what is distributed load w on Typical Interior Fill Beam?
w = (5’)(50psf) = 250 plf
20’, typ.
30’, typ.
Building Plan View 4 3 2 1 A B C D

11. Tributary Widths
What is Tributary Width of Typical Interior Fill Beam?
Answer: 5-ft
If the applied pressure is 50 psf, what is distributed load w on Typical Interior Fill Beam?
w = (5’)(50psf) = 250 plf
20’, typ.
30’, typ.
Building Plan View 4 3 2 1 A B C D

12. Tributary Widths
What is Tributary Width of Typical Interior Fill Beam?
Answer: 5-ft
If the applied pressure is 50 psf, what is distributed load w on Typical Interior Fill Beam?
w = (5’)(50psf) = 250 plf
30’
20’, typ.
30’, typ.
Building Plan View 4 3 2 1 A B C D
What is the Maximum Moment M?
Answer: M = wl2/8 = (250)(302)/8 =
= 28,125 ft-lb

13. Building Elevation View
Tributary Widths
30’, typ.
20’, typ.
Building Elevation View 4 3 2 1 A B C D

14. Building Elevation View
Tributary Widths
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D

15. Building Elevation View
Tributary Widths
What is Tributary Width of Typical Wall Stud?
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D
Wall Stud

16. Building Elevation View
Tributary Widths
What is Tributary Width of Typical Wall Stud?
Answer: 7.5-ft
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D
Wall Stud

17. Building Elevation View
Tributary Widths
What is Tributary Width of Typical Wall Stud?
Answer: 7.5-ft
If the wind pressure is 20 psf, what is distributed load w on Typical Wall Stud?
30’
w = (7.5’)(20psf) = 150 plf
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D
Wall Stud

18. Building Elevation View
Tributary Widths
What is Tributary Width of Typical Wall Stud?
Answer: 7.5-ft
If the wind pressure is 20 psf, what is distributed load w on Typical Wall Stud?
20’
w = (7.5’)(20psf) = 150 plf
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D
What is the Maximum Moment M?
Wall Stud

19. Building Elevation View
Tributary Widths
What is Tributary Width of Typical Wall Stud?
Answer: 7.5-ft
If the wind pressure is 20 psf, what is distributed load w on Typical Wall Stud?
20’
w = (7.5’)(20psf) = 150 plf
30’, typ.
20’, typ.
Building Elevation View
Roof
3rd Floor
2nd Floor
Foundation A B C D
What is the Maximum Moment M?
Answer: M = wl2/8 = (150)(202)/8 =
= 7,500 ft-lb
Wall Stud

20. What is behind that brick wall?

21. What is behind that brick wall?
(Possibly) Concrete Block
Tie
Void Space

22. What is behind that brick wall?
(Possibly)
Insulation
(newer
Construction)

23. What is behind that brick wall?
Studs
(Possibly)
“Brick on Studs” with Insulation
(New, Cheap Construction)

24. What happens when wind strikes this wall?
Wind Pressure

25. What happens when wind strikes this wall?
Brick is supported by ties
Tie
Tie
Tie
Wind Pressure

26. What happens when wind strikes this wall?
Brick is supported by ties
Ties are supported by
Wall Studs
Stud
Stud
Tie
Stud
Tie
Tie
Wind Pressure

27. What happens when wind strikes this wall?
“Studs” (beams) span between …….

28. What happens when wind strikes this wall?
“Studs” (beams) span between floor diaphragms

29. What happens when wind strikes this wall?
“Studs” (beams) span between floor diaphragms

30. What happens when wind strikes this wall?
“Studs” (beams) span between floor diaphragms

32. The Lateral System
Wind Pressure
Wall Studs

33. The Lateral System
Diaphragm
Wind Pressure
Wall Studs

34. The Lateral System Brace C Diaphragm Wind Pressure Wall Studs Brace B
Brace A

35. The Lateral System 30’, typ Brace C Diaphragm 20’ Wind Pressure
Wall Studs
Brace B
Brace A

36. The Lateral System
30’, typ
20’
Wind Pressure
30’, typ

37. Wind Pressure – Distrib. Load to Diaphragm
30’, typ
20’
Wind Pressure
30’, typ
20psf

38. Wind Pressure – Distrib. Load to Diaphragm
30’, typ
20’
Wind Pressure
30’, typ
20psf

39. Wind Pressure – Distrib. Load to Diaphragm
30’, typ
20’
___plf=(10’)(20psf) =w
Wind Pressure
30’, typ
20psf

40. Wind Pressure – Distrib. Load to Diaphragm
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
30’, typ
20psf

41. Wind Pressure – Distrib. Load to Diaphragm
Wind Pressure – Distrib. Load to Foundation Wall
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
200plf=(10’)(20psf) =w
30’, typ
20psf

42. Wind Pressure – Distrib. Load to Diaphragm
Wind Pressure – Distrib. Load to Foundation Wall
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
200plf=(10’)(20psf) =w
30’, typ
20psf

43. Wind Pressure – Resultant Force to Diaphragm
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
18kips = (90’)(200plf) = R
30’, typ
20psf

44. Wind Pressure – Resultant Force to Diaphragm
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
18kips = (90’)(200plf) = R
30’, typ
20psf

45. Wind Pressure – Resultant Force to Diaphragm
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
18kips = (90’)(200plf) = R
30’, typ
20psf

46. Wind Pressure – Resultant Force to Diaphragm
Wind Pressure – Resultant Force to Foundation
30’, typ
20’
200plf=(10’)(20psf) =w
Wind Pressure
18kips = (90’)(200plf) = R
30’, typ
18kips = (90’)(200plf) = R
20psf

48. 1 Story Building
Wind
Brace B
10.8 kips

49. Multi-Story: Brace Forces Additive
Wind
Brace B
10.8 kips

50. Multi-Story: Brace Forces Additive
18 kips
Brace B
10.8 kips

51. Multi-Story: Brace Forces Additive
18 kips
Brace B
10.8 kips

52. Multi-Story: Brace Forces Additive
18 kips
Brace B
10.8 kips
Brace ?

53. Multi-Story: Brace Forces Additive
18 kips
18 kips?
Brace B
10.8 kips
Brace ?

54. Recall: Tributary Widths
18k

55. Recall: Tributary Widths
18k ??

56. Recall: Tributary Widths
18k
36k

57. Recall: Tributary Widths
18k
36k
18k

58. Multi-Story: Brace Forces Additive
18 kips
36 kips
Brace B
10.8 kips
Brace ?

59. Multi-Story: Brace Forces Higher on Lower Floors
18 kips
36 kips
Brace B
10.8 kips
Brace
32.4 kips