Deck 3: Loads on Buildings

Question 1

An average tornado strikes a larger area on the ground than a hurricane.

Answer 1

False

Question 2

Which of the following loads can be estimated with greatest certainty?

A)Earthquake loads
B)Wind loads
C)Snow loads
D)Dead loads
E)Live loads

Answer 2

D

Question 3

Highest wind speeds are usually obtained in

A)tornadoes.
B)wind storms.
C)thunderstorms.
D)hurricanes.

Answer 3

A

Question 4

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.

Question 5

On a leeward wall, the wind pressure

A)increases with height above the ground.
B)is almost constant with height above the ground.
C)decreases with height above the ground.

Question 6

The loads on a beam are generally expressed in

A)lb/ft2.
B)lb/ft.
C)lb.
D)lb/ft3.
E)none of the above.

Question 7

The loads on a column are generally expressed in

A)lb/ft2.
B)lb/ft.
C)lb.
D)lb/ft3.
E)none of the above.

Question 8

The two main categories under which all building loads may be classified are

A)terrestrial loads and celestial loads.
B)dead loads and live loads.
C)gravity loads and lateral loads.
D)first- class and second- class loads.

Question 9

In which of the following roofs will you consider the effect of rain load?

A)Roof with a parapet
B)Roof without a parapet

Question 10

The design wind speed for a location is the peak

A)10- s gust speed.
B)1- s gust speed.
C)5- s gust speed.
D)60- s gust speed.
E)3- s gust speed.

Question 11

The design wind speed for an average- risk building at a location has a probability of occurrence of

A)once in 200 years.
B)once in 100 years.
C)once in 300 years.
D)once in 50 years.
E)none of the above.

Question 12

The roof live load in a building is generally

A)the same as the floor live load.
B)less than the floor live load.
C)greater than the floor live load.

Question 13

Roof live load is a function of the building's occupancy.

Question 14

For most of the United States, the design wind speed for an average- risk building is

A)125 mph.
B)150 mph.
C)95 mph.
D)105 mph.
E)115 mph.

Question 15

The floor live load in a residential occupancy is generally assumed to be

A)20 psf.
B)10 psf.
C)40 psf.
D)5 psf.
E)none of the above.

Question 16

The design wind speed is also referred to as the

A)standard wind speed.
B)basic wind speed.
C)uniform wind speed.
D)official wind speed.
E)straight- line wind speed.

Question 17

Which of the following occupancies has the highest floor live load?

A)Library stack rooms
B)Offices
C)Hotel guest rooms
D)Classrooms
E)Library reading rooms

Question 18

For wind blowing along one of the two major axes of a rectangular building, the side walls are subjected to positive (toward- the- wall)pressure.

Question 19

The loads on a floor are generally expressed in

A)lb/ft2.
B)lb/ft.
C)lb.
D)lb/ft3.
E)none of the above.

Question 20

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.

Question 21

Is the weight of a structural element such as a beam, floor, or roof dead load or live load?

Question 22

Everything else being the same, a building constructed of heavyweight materials is subjected to a greater earthquake load than a building constructed of lightweight materials.

Question 23

A reinforced concrete beam measures 12 in. × 24 in. in cross section. If the density of reinforced concrete is 1 50 lb/ft3, the weight of the beam is

A)350 lb/ft.
B)450 lb/ft.
C)300 lb/ft3.
D)300 lb/ft.
E)300 lb.

Question 24

The total approximate dead load of a floor in a typical wood frame residential building is

A)5 psf.
B)30 psf.
C)10 psf.
D)50 psf.
E)none of the above.

Question 25

According to the geologists, the earth's surface is composed of several segments that are called

A)segmental plates.
B)tectonic plates.
C)earth segments.
D)geological segments.
E)surface plates.

Question 26

The live loads on a building are classified under two types. Name them.

Question 27

In a building whose structural system consists of columns, beams, and floor and roof slabs, the columns are spaced at 40 ft on center in one direction and 25 ft on center in the other direction. What is the tributary area for a corner column?

A)500 ft2
B)1,000 ft2
C)250 ft2
D)1,000 ft
E)None of the above

Question 28

Check all the following loads that are gravity loads. Snow load
Wind load Rain load
Earthquake load Blast load
Dead load Live load

Question 29

The total approximate gravity load on a floor in a typical wood frame residential building is

A)50 psf.
B)30 psf.
C)5 psf.
D)10 psf.
E)none of the above.

Question 30

What is the unit of measurement for loads on a linear building element, such as a beam, in the U.S. System of units?

Question 31

An earthquake measuring 7.0 on the Richter scale is

A)twice as strong as a 6.0 earthquake.
B)10 times stronger than a 6.0 earthquake.
C)100 times stronger than a 6.0 earthquake.
D)500 times stronger than a 6.0 earthquake.
E)none of the above.

Question 32

Which is a smaller unit of measurement pound or Newton? Give the approximate relationship between them.

Question 33

What is the difference between floor live load and occupancy load?

Question 34

What is the unit of measurement for loads on a surface element, such as a floor or roof in the U.S. System of units?

Question 35

The region of the United States that is relatively more earthquake prone is the

A)eastern United States.
B)western United States.
C)northern United States.
D)southern United States.
E)none of the above.

Question 36

In a building whose structural system consists of columns, beams, and floor and roof slabs, the columns are spaced at 40 ft on center in one direction and 25 ft on center in the other direction. What is the tributary area for an interior column?

A)1,000 ft
B)1,000 ft2
C)500 ft2
D)250 ft2
E)None of the above

Question 37

The design snow load on a roof is a function of

A)roof slope.
B)wind exposure classification of the site.
C)ground snow load of the location.
D)all of the above.
E)both A and B.

Question 38

The number of mild (minor to very minor)earthquakes occurring on the earth is almost

A)1 or 2 per year.
B)10 to 20 per year.
C)100 per year.
D)1,000 per year.
E)several thousand per year.

Question 39

With respect to wind pressure, a building site is classified in terms of

A)Exposures B, C, and D.
B)Exposures A, B, and C.
C)Exposures X, Y, and Z.
D)Exposures P, Q, R, and S.
E)Exposures A, B, C, and D.

Question 40

The unit of measurement for load on a column in the U.S. System of units is pound (#)or kip. What is the corresponding unit in the SI System of units?

Question 41

What is the minimum roof live load?

Question 42

In determining wind pressures on a building, the most important factor is the design wind speed for the location. What is the corresponding factor for determining the roof snow load?

Question 43

Although the highest wind speeds occur in tornadoes, the building code ignores tornado wind speeds in specifying the design wind speed for a location. Why?

Question 44

The design wind speed for a location has a return period of 700 years for a normal- risk building. What is the return period for a (i)a low- risk building and (ii)a high- risk building?

Question 45

What is the role of tectonic plates with earthquakes?

Question 46

What is the minimum slope required of a roof?

Question 47

What is the difference between primary roof drains and secondary roof drains?

Question 48

A rectangular building with a near- flat roof is acted upon by wind at right angle to one of the walls. Which of the following envelope surfaces will be acted upon by positive (toward- the- surface)pressure and which envelo surfaces will be subjected to suction (negative pressure)?
Windward wall Leeward wall Side walls
Roof

Question 49

For which of the following building types must the rain load on the roof be determined: (i)a building with steep roof and (ii)a building with a parapeted flat roof?

Question 50

Does the roof live load vary with occupancy, similar to floor live load?

Question 51

While tornado wind speeds are ignored in specifying the design wind speed for a location, the hurricane and thunder storm wind speeds are not. Why?

Question 52

In terms of snow load, what is a cool roof and what is a warm roof?

Question 53

In which situation(s), is the secondary roof drainage system required and in which situation(s)is it not required?

Question 54

Check the occupancy, among those given below, for which the design floor live load is the largest. Single family residence
Office building Library reading room Library stack room Parking garage floor

Question 55

How does wind pressure vary with height above ground on a building with a rectangular footprint?

Question 56

What is the relationship between wind speed, V, and the resulting wind pressure, P, on a building surface?

Question 57

Name the most important factor that affects the wind pressures on building surfaces.

Question 58

What are tectonic plates and how are they related to crustal plates?

Question 59

What does the exposure classification of a building imply with respect to wind?

Question 60

How does the wind exposure classification affect the roof snow load on a building?

Question 61

Name two most important properties of the building structure that affect its response to an earthquake.

Question 62

Using sketches and notes, explain how roof slope affects wind pressure on a roof.

Question 63

What is the range over which the Richter scale extends? What is the approximate maximum Richter magnitude earthquake recorded so far?

Question 64

Explain why lightweight building materials are preferred in earthquake- prone locations.

Question 65

What is the Richter scale and what does it measure? What is the difference between the amounts of energy released by two earthquakes that are 8.0 and 6.0 on the Richter scale? Show calculations.

Question 66

Explain the differences between Wind Exposure Categories B, C, and D.

Question 67

Using sketches and notes, explain the types of wind pressure that occur on a rectangular building.

Question 68

How many earthquakes occur on earth every year?

Question 69

What is the approximate wind speed in a tornado? Explain why tornado wind speeds are not considered in determining the design wind speed for a location.

Question 70

List three important factors and the manner in which they affect the number of fatalities caused by building collapses in an earthquake (EQ).

Question 71

Explain the major differences between designing buildings for earthquake resistance and for wind resistance.

Question 72

What is the design wind speed for average- risk building: (a)for most locations in the United States and (b)for coastal areas of the western United States?

Question 73

What is the commonly used scale to measure earthquake intensity and who is credited for devising the scale?

Question 74

Using sketches and notes, explain the ballooning effect in buildings.

Question 75

What is the weight of 1 sq ft of 1- 1/8 in.- thick OSB sheathing? Density of OSB = 36 #/ft3.

Question 76

What types of construction are (a)suitable and (b)unsuitable in an earthquake- prone region? Explain your answer, giving reasons.

Question 77

What is the difference between: (a)dead load and live load, (b)floor live load and roof live load, and (c)roof live load and rain load? Explain with the help of examples.