CVEN 444 (Conceptual Q's)

An under reinforced section is one in which…

1. The steel reinforcement yields after the concrete has reached its maximum usable strain

2. The steel reinforcement yields at the same time concrete reaches its maximum usable strain

3. The steel reinforcement yields before the concrete reaches its maximum usable strain

3

A minimum steel reinforcement requirement is imposed in beam design to…

1. Prevent a brittle type failure from occurring

2. prevent the steel reinforcement from yielding

3. prevent the concrete from cracking

1

Time dependent volume changes due to shrinkage in concrete start immediately after the concrete is set. Most of these changes occur….

1. Within one year

2. After one year

3. when concrete is more than 5 years old

1

We need safety factors in RC design because….

1. all design variable are deterministic in nature

2. all design variables are random in nature

3. material properties are well known but loads are not

2

Concrete is a material stronger in ___ than it is in ____

compression; tension

an over-reinforced section is….

1. The steel reinforcement yields after the concrete has reached its maximum usable strain

2. The steel reinforcement yields at the same time concrete reaches its maximum usable strain

3. The steel reinforcement yields before the concrete reaches its maximum usable strain

1

The stress-strain behavior of concrete in compression is linear at stress levels..

1. up to f’c

2. up to about f’/2

3. between f’c/2 and f’c

2

Load combinations are used in design because there’s…..

1. a high probability of all maximums occurring at the same time

2. a low probability of all maximums occurring at the same time

3. certainty about the maximum expected loads

The bending stresses in a reinforced concrete element BEFORE yielding…

1. using whitney’s block

2. poission’s coeeficient

3. using hook’s law

3

a balanced condition occurs when the tension steel yields..

1. before the concrete reaches its maximum usable strain

2. at the same time the concrete reaches its maximum usable strain

3. after the concrete has reached its maximum usable strain

2

Compression reinforcement helps increase….

1. the deflections in an RC beam

2. The shear capacity of an RC beam

3. the ductility of an RC beam

3

Concrete cover is important because…
1. it protects the reinforcement from corrosion and overheating

2. Helps resist tension stresses

3. increases the shear capacity

1

The presence of large shearing stresses in a beam is characterized by..

1. diagonal cracks

2. vertical cracks

3. horizontal cracks

Shear failures are of the..

1. ductile type

2. brittle type

3. slow type

2

The transfer of force from a straight line to the concrete is achieved mainly via…

1. normal stresses

2. shearing stresses

3. 3. bonding stresses

3

The development length is the shortest length of bar in which the bar stress…

1. can increase from zero to the yield strength

2. remain at a constant value

3. go from the ultimate stress to the breaking point

1

The development length, ld, of a smaller diameter bar is…

1. longer than ld of a bigger diameter bar

2. the same as “ “

3. shorter than “ “

3

in a compression member (column), the presence of a bending moment…

1. increases the axial capacity of the member

2. decreases “ “

3. does not modify the axial capacity of a member

2

The distinction between a ‘short’ column and a slender column is based on..

1. The likelihood of failing in compression

2. the likelihood of failing in tension

3. the likelihood of experiencing lateral buckling

3

The continent where we live is named America after…

1. a native warrior who fought against the European colonists

2. an Italian cartographer and explorer

3. an army general and military strategist who fought against the British army

2

Lateral compression (confinement) in an RC member..

1. increases the deformation capacity (ductility) but not the strength

2. increases the strength but not the deformation capacity

3. increases both the strength and the deformation capacity

3

The moment vs curvature diagram shown corresponds to..

1. a section that fails in a brittle manner

2. an over reinforced section

3. an under reinforced section

3

In a one way slab system, the loads are carried by the slab in..

1. both directions

2. the long direction

3. the short direction

3

A one way slab system is typically used in the presence of…

1. rectangular panels

2. square panels

3. irregular non rectangular panel

1

The minimum shear reinforcement requirement is intended to….

1. avoid a compression controlled failure

2. ensure that no shear cracks occur

3. prevent a sudden shear failure

3

Which of the following requires a shorter development length..

1. a straight bar

2. a hooked bar

3. a headed bar

3

In tall buildings, f’c for the columns is typically..

1. the same as for the flooring system

2. smaller than for the flooring system

3. larger than for the flooring system

3