Chapter 3: Loads & Buildings
Dead Loads
Always present; Load does not vary over time. Computed by multiplying the volume by the density of the material.
Floor live load
Depends on the occupancy and the use of the building. Also called the occupancy load.
Basic wind speed
Design wind speed is also referred to as
kilopound (kip)
Equal to 1000 lb
False
For wind blowing along one of the two major axes of a rectangular building, the leeward wall is subjected to positive (toward-the-wall) pressure.
True
For wind blowing along one of the two major axes of a rectangular building, the windward wall is subjected to positive (toward-the-wall) pressure.
False
For wind blowing along one of the two major axes of rectangular building, the side walls are subjected to positive (toward-the-wall) pressure.
10psf
Generally assumed dead load of a floor with the typical wood frame residential building
40psf
Generally assumed measurement of a floor live load in a residential occupancy
Tornadoes
Highest wind speeds are usually obtained in
Gravity Loads (vertical loads)
Load caused by the gravitational pull of the earth & act in the vertical direction. Further classified as dead loads and live loads
Lateral Loads
Load in which the two primary sources on buildings are wind and earthquakes
Dead Loads
Load that can be estimated with greatest certainty.
Live load
Load whose magnitude and placement change with time. Further divided to floor live load and roof live load
Ductile materials
Materials that can sustain permanent deformation prior to failure
Pounds per square foot (psf)
Measurement in which the load is distributed over a surface such as a floor or a roof.
ft^2
Measurement used for tributary area
Library stack rooms
Occupancy with the highest floor live load
Several thousand
The amount of mild earthquakes occurring on the earth
3-s gust speed
The design wind speed for a location is the peak of
115 mph
The design wind speed for an average risk building in the United States.
lb/ft
The loads on a beam are generally expressed in
lb
The loads on a column are generally expressed in
lb/ft^2
The loads on a floor are generally expressed in
Western United States
The region of the United States that is relatively more earthquake prone.
Less
The roof live load is generally less, greater, or same as a floor live load
Tectonic plates
The several segments which compose the earths surface
50 psf
The total approximate gravity load on a floor in a typical wood frame residential building
Gravity Loads & Lateral Loads
The two main classifications of loads
False
True or false. Roof live load is a function in the buildings occupancy.
Roof live load
Type of live load generally given as 20 psf acting on the horizontal projected area on the roof.
Leeward wall
Type of wall with wind pressure that is almost constant with height above ground.
Pounds (lbs)
Unit for measuring building loads
(lb/ft)
Unit used to measure the load on a beam
Roof with a parapet
What kind of roof will you consider the effect of rain load?
Exposures B,C,D
With respect to wind pressure, a building site is classified in these exposures