Building Collapse (Ch 2)

Question 1

3 basic methods of wood-framed residential blds

Answer 1

• Balloon Construction (ext walls have studs that run continuously from foundation sill to top plate)
• Braced-frame Construction (post-and-girt), mortise-and-tenon joints, walls often fail in inward/outward collapse
• Platform Construction

Question 2

Beams: 3 methods of support

Answer 2

• Cantilever Beam Support: ornamental stone cornice, marquee, canopy, fire escape, sign 90^o to wall
• Continuous Beam Support: supported at both ends and at the center (most stability during a fire)
• Single Supported Beam: supported at both ends.

Question 3

Buttress

Answer 3

• Wall reinforcement or brace built on outside of building (wall column). Inside of wall called pilaster.

Question 4

Hierarchy of Building elements

Answer 4

• Less-to-more in collapse seriousness
  
  • Decks
  • Beams/Floor and Roof
  • Girders
  • Columns
  • Bearing Walls

Question 5

Loads: types

Answer 5

• Axial Load (passes through the center)
• Concentrated Load
• Dead Load (static, permanent, part of structure and permanent equipment)
• Eccentric Load
• Impact Load
• Lateral Load (wind, tips of ladders, explosion shock waves, hose streams)
• Live Load
• Static Load
• Torsional Load
• Wind Load

Question 6

Primary Structural Member

Answer 6

Structure that supports another structural member in the same building (bearing wall, column, girder).

Question 7

Ridgepole

Answer 7

Horizontal timber that frames highest point of a peak roof (rafters fastened to it).

Question 8

Stress: definition and types

Answer 8

A force exerted upon a structural member that strains or deforms its shape.

• Compression
• Sheer
• Tension

Question 9

Walls: types

Answer 9

• Area
• Bearing
• Fire
• Free-Standing (exposed to the elements on both sides)
• Parapet
• Party (bearing wall that supports floors and roofs of two buildings)
• Spandrel (portion of interior wall between the top of one window opening and the bottom of another)
• Veneer

Question 10

Wall hierarchy

Answer 10

Less-to-more stable

• Free-standing
• Non-bearing
• Bearing