CM113 Exam 1

The floor live load in a residential occupancy is generally assumed to be: A. 40 psf B. 10 psf C. 20 psf D. 5 psf E. none of the above

A

The loads on a beam are generally expressed in: A. lb/ft^2 B. lb/ft C. lb D. lb/ft^3 E. none of the above

B

The units of modulus of elasticity are a. psi b. ksi c. Pa d. GPa e. all of the above

E

What is generally suppose to happen to the upper portion if the lower portion of a building moves?

The upper portion should stay still

If there is 1000 lbs of compression and 1000 lbs of tension, what is the load neutral axis?

0

What is the moisture percentage for dry lumber?

19% or less

What is the PSF for roof loads?

20 pounds per square foot

What is the force on the building if the wind speed doubles?

4 times the force

Concrete is a. an elastic material b. a plastic material c. an elastic plastic material d. none of the above

A

Hydrated lime is available in two types, which are referred to as ______. a. Types N and S lime b. Types I and II lime c. Types X and Y lime d. Types A and B lime e. Types 1 and 2 lime

A

A material that is weak in tension a. strong in shear b. weak in shear c. no relationship between the shear and tensile strengths of a material

B

A material that is weak in tension is a. strong in bending b. weak in bending c. no relationship between the tensile and bending strengths of a material

B

The compressive strength of concrete is generally measured _____. a) when the concrete is fresh b) 28 days after casting the concrete in a test specimen c) 14 days after casting the concrete in a test specimen d) 7 days after casting the concrete in a test specimen e) 1 day after casting the concrete in a test specimen

B

The test specimen used for determining the compressive strength of concrete in the United States is a _____. a. 6-in. diameter, 6 in.-high cylinder b. 6-in. diameter, 12 in.-high cylinder c. 6-in. diameter, 18 in.-high cylinder d. 6-in. diameter, 12 in.-high cone

B

What two main categories under which all building loads may be classified are: A. dead loads and live loads B. gravity loads and lateral loads C. terrestrial loads and celestial loads D. first-class and second-class loads

B

Which gives greater warning before failure? a. A brittle material b. A ductile material

B

On a leeward wall, the wind pressure A. Increases with height above the ground B. Decreases with height above the ground C. Is almost constant with height above the ground

C

The bearing strength of a material is closely related to its a. bending strength b. tensile strength c. compressive strength d. modulus of elasticity e. none of the above

C

The bending stresses along the neutral axis of a beam are a. minimum b. maximum c. zero d. none of the above

C

The loads on a column are generally expressed in: A. lb/ft^2 B. lb/ft C. lb D. lb/ft^3 E. none of the above

C

The design snow load on a roof is a function of A. Ground snow load of the location B. Roof slope C. Wind exposure classification of the site D. All of the Above E. Both A and B

D

The design wind speed for a location is the peak A. 60-s gust speed B. 10-s gust speed C. 5-s gust speed D. 3-s gust speed E 1-s gust speed

D

The horizontal blocking in wood studs helps prevent a. compressive failure of studs b. shear failure of studs c. tensile failure of studs d. buckling of studs

D

The most commonly specified type of portland cement is ____. a. Type C b. Type III c. Type PC1 d. Type I/II e. Type II/III

D

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

E

In a high-rise building, the concrete may be brought from the ground to the location of placement by _____. a. chutes b. buckets c. pumping d. (a) or (b) e. (b) or (c)

E

The design wind speed for an average-risk building at a location has a probability of occurrence of A. Once in 300 years B. Once in 200 years C. Once in 100 years D. Once in 50 years E. None of the above

E

The design wind speeds is also referred to as the: A. Standard wind speed B. Official wind speed C. Uniform wind speed D. Straight-line wind speed E. Basic wind speed

E

A well-graded coarse aggregate is one in which the size of all aggregate particles is approximately the same. (T/F)

False

After concrete has been placed in the form, it should be compacted as much as is economically practical. (T/F)

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 (T/F)

False

For wind blowing along one of the two major axes of a rectangular building, the sidewall is subjected to positive (toward the wall) pressure (T/F)

False

In most materials, the safety margin for compressive stress and bending stress is the same (T/F)

False

Quicklime is most commonly used in building constructions. (T/F)

False

Roof live load is a function of the building's occupancy. (T/F)

False

White portland cement is generally weaker than normal (gray-colored) portland cement. (T/F)

False

an average tornado strikes a larger area on the ground than a hurricane (T/F)

False

What's stronger parallel or perpendicular to the grain slope?

Parallel

What module of elasticity is elasticity of?

Stiffness, how something deforms and reverts during and after load use and removal

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

True

Everything else being the same, a concrete with a larger coarse aggregate requires less portland cement and water paste to give the same concrete strength. (T/F)

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. (T/F)

True

In a typical stress strain diagram of a material, the stress is generally plotted along the vertical axis? (T/F)

True

Lightweight structural concrete is heavier than insulating concrete. (T/F)

True

Quicklime reacts readily with water (T/F)

True

Stress Equation

force/area or P/A

What is the moisture percentage for green lumber?

more than 19%

Modulus of Elasticity

stress/strain

In which of the following roofs will you consider the effect of rain load? A. Roof with a parapet B. Roof without a parapet

A

Lime is made by a. heating crushed limestone and then pulverizing it. b. mixing crushed limestone with water and then pulverizing the mixture. c. mixing crushed limestone with sulfuric acid and then pulverizing the mixture. d. mixing crushed limestone with nitric acid and then pulverizing the mixture

A

The finishing operations of a concrete surface usually involve striking, floating, and troweling. The sequence in which these three operations are generally performed is _____. a. striking, floating, and troweling b. floating, striking, and troweling c. striking, troweling, and floating d. troweling, floating, and striking

A

The loads on the floor are generally expressed in: A. lb/ft^2 B. lb/ft C. lb D. lb/ft^3 E. none of the above

A

The material in an arch is primarily in A. compression B. tension C. both tension and compression D. Shear E. none of the above

A

The primary purpose of ties in a reinforced concrete columns is to a. prevent the buckling of vertical reinforcement in the column b. prevent the crushing of concrete c. increase the shear resistance of the column d. none of the above

A

Modulus of elasticity refers to how a. strong a material is b. stiff a material is c. elastic a material is d. serviceable a material is e none of the above

B

One of the important cementitious ingredients in making Roman concrete was ______. a. clay b. volcanic ash c. sand d. Portland cement e. none of the above

B

The total approximate dead load of a floor in a typical wood frame residential building is a. 50 psf b. 30 psf c. 10 psf d. 5 psf e. none of the above

C

When a cable or rope is compressed by a force, what is the the compressive stress in it? a. equal to the force applied b. force divided by the cross sectional area of the rope c. Zero d. Infinite e. None of the abve

C

Which of the following materials is a pozzolana? a. Portland cement b. Lime c. Fly ash d. Sand e. Concrete

C

Which of the following occupancies has the highest floor live load? A. Classrooms B. Hotel guest rooms C. Library stack rooms D. Library reading rooms E. Offices

C

A 20 ft high column shortens by 0.6 in under a load. What is the resulting strain in the column? a. 0.0020 b. 0.0020 in c. 0.0025 in d. 0.0025 e. None of the above

D

A rectangular column measuring 12in x 12 in in cross section carries a load of 18kips. What is the stress in the column? a. 18 kips b. 18 ksi c. 2.25 ksi d. 125 psi e. None of the above

D

Highest wind speeds are usually obtained in A. Hurricanes B. Wind Storms C. Thunderstorms D. Tornadoes

D

The aggregate for concrete is generally subdivided into coarse aggregate and fine aggregate. The distinction between the two types of aggregate is based on the _____. a. aggregate's strength b. aggregate's surface texture c. aggregate's density d. aggregate's particle size e. aggregate's parent rock

D

The region of the United States that is relatively more earthquake prone is the a. Northern United States b. Southern United States c. Eastern United States d. Western United States e. None of the above

D

The slump concrete is a measure of the ____. a. compressive strength of concrete b. tensile strength of concrete c. modulus of elasticity of concrete d. workability of concrete

D

The stirrups in a reinforce concrete beam are used to a. increase the strength of the beam in bending b. reduce the deflection of the beam c. increase the durability of the beam d. increase the strength of the beam in shear e. none of the above

D

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

E

The test specimen used for determining the compressive strength of concrete in the United States is a a. cube measuring 12x2x12 b. cube measuring 6x6x6 c. prism measuring 6x6x12 d. cylinder measuring 12 in diameter and 6 high e. cylinder measuring 6 in diameter and 12 high

E

What is the yield stress of grade 60 reinforcing steel? a. 60 lb b. 6,000 psi c. 6,000 lb d. 60 psi e. None of the above

E

With respect to wind pressure, a building site is classified in terms of A. Exposures A, 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 B, C, and D

E

The primary purpose of the longitudinal steel bars in a reinforced concrete beam is to overcome the weakness of concrete in tension (T/F)

True

The stress strain diagram of mild steel is nearly a straight line up to the yield point? (T/F)

True

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^2 b. 1,000 ft c. 500 ft d. 250 ft^2 e. None of the above

A

In a steel column that rests on a concrete footing, the area of the bearing plate used is generally a. greater than the cross sectional area of the column b. equal to the cross sectional area of the column c. smaller than the cross sectional area of the column

A

The roof live load in a building is generally A. Less than the floor live load B. Greater than the floor live load C. The same as the floor live load

A

The slump of concrete is measured ____. a. when the concrete is fresh b. 28 days after casting the concrete in a test specimen c. 14 days after casting the concrete in a test specimen d. 7 days after casting the concrete in a test specimen e. 1 day after casting the concrete in a test specimen

A

The total approximate gravity load on a floor in a typical wood frame residential building is a. 50 psf b. 30 psf c. 10 psf d. 5 psf e. none of the above

A

When we determine the strength of concrete using the test specimens, we determine the concrete's a. ultimate compressive stress b. ultimate tensile stress c. ultimate shear stress d. modulus of elasticity e. all of the above

A

Which of the following loads can be estimated with the greatest certainty? A. Dead loads B. Live Loads C. Wind Loads D. Earthquake Loads E. Snow Loads

A

A pozzolanic material must be composed mainly of ______. a. microscopic silica b. microscopic and amorphous silica c. microscopic and crystalline silica d. silica and alumina e. amorphous silica and alumina

B

ASTM specifications classify portland cement into five basic types, referred to as _____/ a. Types A, B, C, D, and E b. Types I, II, III, IV, and V c. Types PC1, PC2, PC3, PC4, and PC5 d. Types X, Y, Z, P, and Q e. none of the above

B

Hydrated lime is obtained by treating ______. a. slaked lime with water b. quicklime with water c. limestone with water d. slaked lime with portland cement e. quicklime with portland cement

B

In a No. 4 sieve, the dimensions of voids are approximately ____. a. 4 in. x 4 in. b. 1/4 in. x 1/4 in. c. 2 in. x 2 in., giving an area of approximately 4.0 in^2 d. 1 in. x 4 in. e. none of the above

B

The allowable stress in a material is generally a. equal to ts ultimate stress b. less than its ultimate stress c. greater than its ultimate stress d. none of the above

B

Which of he following beam cross section is structurally more efficient in bending? a. Rectangular (solid) section b. I section

B

Which of the following beam cross sections is structurally more efficient in bending? a. Rectangular (solid) section b. Tubular section

B

Which type of portland cement is commonly used in making precast concrete members? a. Type C b. Type III c. Type PC1 d. Type I/II e. Type II/III

B

Why do we use wood for construction?

Because its a renewable material, it regrows, relatively low-cost, and easy to work with

A reinforced concrete beam measures 12 in. X24 in. in cross section. If the density of reinforced concrete is 150 lb/ft^3, the weight of the beam is a. 450 lb/ft b. 350 lb/ft c. 300 lb/ft d. 300 lb e. 300 lb/ft^3

C

According to the geologists, the earth's surface is composed of several segments that are called a. Earth segments b. Surface plates c. Tectonic plates d. Geological segments e. Segmental plates

C

For most of the United States, the design wind speed for an average-risk building is A. 95 mph B. 105 mph C. 115 mph D. 125 mph E. 150 mph

C

Hydrated lime-water paste sets and hardens due to ______. a. chemical reaction of water with lime. b. chemical reaction of the oxygen in the air with lime. c. chemical reaction of the carbon dioxide in the air with lime. d. chemical reaction of the nitrogen in air with time. e. chemical reaction of the water in lime with the carbon dioxide in air.

C

In a simple 3 member truss consisting of 2 rafters and a tie, each member is in: a. compression b. tension c. either tension or compression d. shear e. both tension and compression

C

In a suspension bridge, which members(s) is (are) in compression? a. Suspension cable b. Hanger cables c. Support pylons d. both suspension cable and hanger cables e. None of the above

C

Low carbon (mild) steel is a. an elastic material b. a plastic material c. an elastic-plastic material d. none of the above

C

The consolidation and compaction of concrete on a construction site are generally done ______. a. manually using a 2-in.-diameter, 3-ft-long steel rod b. manually using a 1-in.-diameter, 3-ft-long steel rod c. using a power-driven rod vibrator d. using a power-driven plate vibrator

C

The main ingredient used in the manufacture of portland cement is ____. a. marble b. granite c. limestone d. sand e. iron ore

C

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. 1,000 ft^2 b. 1,000 ft c. 500 ft d. 250 ft^2 e. None of the above

D

In relation to its compressive strength, the tensile strength of concrete is a. much higher b. slightly higher c. nearly the same d. much lower e slightly lower

D