-
What are the 5 types of building construction?
- 1. Fire resistive
- 2. Noncombustible
- 3. Masonry-ordinary
- 4. Heavy Timber
- 5 Wood Frame
-
Most important part of a buildings design in regards to exposure fires?
Height and width of the building
-
What are the potential sources of failure of a building during a fire?
- Structural integrity
- building systems
- design definciency
-
Accessability-Manual fire alarm stations must not be more than___ft and not less than ___ft above the floor level so they may be reached from a wheelchair
- not higher than 4 1/2ft
- not less than 3 1/2ft
-
What is the fire resistance rating requirement of columns supporting floors in a type 1 building?
3 hrs
-
What is the FRR of walls enclosing exit stairwells?
1 or 2 hr rating
-
Type 1 construction FRR for
1. Bearing walls, columns, and beams?
2. Floor construction?
3. Roof Deck?
- 1.) 2 to 4 hrs
- 2.) 2 to 3 hrs
- 3.) 1 to 2 hrs * some codes omit roof standard when it is located above 20ft from the floor
-
Two most common methods of type 1 construction?
- re-inforced concrete
- protected steel frame
-
Type 2 construction details
- Noncombustibles
- may be protected or unprotected
- unprotected steel most commonly used
-
Type III construction
- Type IIIA= 1hr FRR for interior members
- Type IIIB= has 0 fire resistive rating for interior members
- wood= not uncommon to have 2X10 inch joists for floors
- Fundamental concern is concealed space combustibility
-
Type IV Heavy Timber details
- typically masonry exterior
- beams,columns, floors and roofs made of solid or laminated wood with dimensions greater than type III
- Floors can be 6X10
-
Type V contruction has 2 types?
Many have what FRR?
- Balloon frame and Platform frame
- 1HR FRR typiccally accompplished with two pieces of gypsum board 1 on each side
-
Wind exerts the following 3 basic forces, describe?
- Direct pressure-the impact effect of wind on a surface. force may be reduced by streamlining the surface
- Aerodynamic drag- when wind encounters an object its fluid nature causes it to flow around an object. This exerts drag on an object.
- Negative pressure- a suction effect produced on the down wind side resulting in outward pressure
-
What are winds 3 secondary effects?
- Rocking effects- due to velocity variations
- Vibrations- wind passing over a surface may cause vibration depending on the velocity
- Clean off effect- tendency of wind to dislodge objects from a building
-
2 pressure effects of soil on building?
- Active soil pressure- soil vs. foundation
- Passive soil pressure- foundation vs. soil
-
Describe dead loads and live loads?
- Dead loads- weight of structural components, usually any permanent attached feature
- Live loads- not fixed or permanent; usually applied to occupants, contents and the wight of snow, rain on roof
-
Snow loads maybe as much as___lbs per sq. foot?
60lbs
-
Describe Static and Dynamic loads?
- Static loads- are loads that are steady or applied gradually
- Dynamic loads- loads that involve motion
-
Describe the interior forces or stress? (3)
- Tension- pulls materials apart
- Compression- squeezes materials
- Shear- slide one plane of a material past an adjacent plane
-
Exterior loads are classified according to the manner applied, what are they? (3)
- Axial load-applied to center of cross section of a structural member and perpendicular to that cross section
- Eccentric load- Perpendicular to cross section does not pass through cross section
- Torsional load- offset from the center of the cross section of the structural member and at an angle to or in same plane as cross section
-
Define beams
- carry load perpendicular to its longitudal dimensions
- * tall beams are capable of supporting greater loads than shorter beams
-
Define Columns
- members designed to support axial compression
- tall and thin=buckle failure
- squatty= crush failure
-
3 basic structural systems?
- structural bearing walls- support spanning elements such as beams, trusses, and precast concrete slabs aka bearing walls
- Post and Beam construction- typically 6X8; when supporting roof spacing 24 inches apart unlike studs 12 to 16inches apart
- Slab + column- most frequently in concrete structures
|
|
