Construction Materials Chapter 4 - TEST 1

In a typical stress-strain diagram of a material, the stress is generally plotted along the vertical axis. A/ True B/ False

A/ True

The primary purpose of longitudinal steel bars in a reinforced concrete beam is to overcome the weakness of concrete in tension. A/ True B/ False

A/ True

The stress-strain diagram of mild steel is nearly a straight line up to the yield point. A/ True B/ False

A/ True

Which gives greater warning before failure? A/ A brittle material B/ A ductile material

B/ A ductile material

In most materials, the safety margin for compressive stress and bending stress is the same. A/ True B/ False

B/ False

In a suspension bridge, which member(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/ Support pylons

In a simple three-member truss consisting of two 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/ Zero

When a cable or rope is compressed by a force, what is the compressive stress in it? A/ Equal to the force applied B/ Force divided by the cross-sectional area of rope C/ Zero D/ Infinite E/ None of the above

C/ Zero

Low-carbon (mild) steel is A/ an elastic material. B/ a plastic material. C/ an elastic-plastic material. D/ none of the above.

C/ an elastic-plastic material.

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/ compressive stregnth

The bending stresses along the neutral axis of a beam are A/ minimum. B/ maximum. C/ zero. D/ none of the above.

C/ zero.

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/ 0.0025

A rectangular column measuring in cross section carries a load of 18 kips. What is the stress in the column? A/ 18 kips B/ 18 ksi C/ 2.25 ksi D/ None of the above E/ 125 psi

D/ None of the above

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/ buckling of studs.

What is the yield stress of grade 60 reinforcing steel? A/ 60 lb B/ 6,000 lb C/ 6,000 psi D/ 60 psi E/ None of the above

E/ None of the above

Concrete is A/ an elastic material. B/ a plastic material. C/ an elastic-plastic material. D/ none of the above.

A/ an elastic material

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/ compression.

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/ greater than the cross-sectional area of the column.

The primary purpose of ties in a reinforced concrete column 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/ prevent the buckling of vertical reinforcement in the column.

Which of the following beam cross sections is structurally more efficient in bending? A/ Rectangular (solid) section B/ I-section

B/ I-section

Which of the following beam cross sections is structurally more efficient in bending? A/ Rectangular (solid) section B/ Tubular section

B/ Tubular section

The allowable stress in a material is generally A/ equal to its ultimate stress. B/ less than its ultimate stress. C/ greater than its ultimate stress. D/ none of the above.

B/ less than its ultimate stress.

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/ stiff a material is.

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.

B/ ultimate tensile stress.

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/ weak in bending.

A material that is weak in tension is A/ strong in shear. B/ weak in shear. C/ no relationship between the shear and tensile strengths of a material.

B/ weak in shear.

The stirrups in a reinforced 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/ increase the strength of the beam in shear.

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/ much lower.

The unit of modulus of elasticity is A/ psi. B/ ksi. C/ Pa. D/ GPa. E/ all of the above.

E/ all of the above.

The test specimen used for determining the compressive strength of concrete in the United States is a A/ cube measuring 12in X 12in X 12in B/ cube measuring 6in X 6in X 6in C/ prism measuring 6in X 6in 12in D/ cylinder measuring 12in. in diameter X 6in. high E/ cylinder measuring 6in. Diameter x 12in High

E/ cylinder measuring