Question 1

Explain what load factor is in structural design.

Accepted Answer

Load factor is one of the two safety factors used in the design of structures. We design structures for a greater load than they are expected to carry. In other words, we multiply the expected loads with a factor
> 1.0. This factor is called the load factor. The load factor takes into account the uncertainty in determining the loads on the structure.

Question 2

Explain the concept of buckling. Explain whether buckling would occur if a member is subjected to bending. What measures do we adopt to prevent the buckling failure of building components?

Accepted Answer

Buckling is a structural failure mode that occurs when a member, such as a column or beam, is subjected to compressive loads. It is characterized by sudden, catastrophic failure due to the member's inability to support the applied load, leading to a sudden lateral deflection or collapse.

When a member is subjected to bending, buckling can occur if the compressive stress exceeds the critical buckling stress for the material and geometry of the member. In bending, the top of the member is in compression while the bottom is in tension. If the compressive stress exceeds the critical buckling stress, the member will buckle and fail.

To prevent buckling failure of building components, several measures can be adopted. These include using proper design and material selection to ensure that the member can withstand the expected compressive loads without buckling. Additionally, reinforcing the member with bracing or stiffeners can help prevent buckling by increasing its resistance to lateral deflection. Regular inspection and maintenance of building components can also help identify and address any potential issues that could lead to buckling failure. Overall, a combination of proper design, material selection, reinforcement, and maintenance is essential to prevent buckling failure in building components.

Question 3

The test specimen used for determining the compressive strength of concrete in the United States is a

Accepted Answer

A) cube measuring 6 in. × 6 in. × 6 in. 
B) cylinder measuring 12 in. in diameter × 6 in. high. 
C) cylinder measuring 6 in. in diameter × 12 in. high. 
D) prism measuring 6 in. × 6 in. × 12 in. 
E) cube measuring 12 in. × 12 in. × 12 in. 
A) cube measuring 6 in. × 6 in. × 6 in. 
B) cylinder measuring 12 in. in diameter × 6 in. high. 
C) cylinder measuring 6 in. in diameter × 12 in. high. 
D) prism measuring 6 in. × 6 in. × 12 in. 
E) cube measuring 12 in. × 12 in. × 12 in. C

Question 4

What is the unit of measure for strain?

Accepted Answer

Because strain is the ratio of

Question 5

Explain with the help of a sketch why a brittle material is weak in shear.

Accepted Answer

A brittle material is weak in shear beca

Question 6

The saw blades used for cutting masonry, concrete and stone are made of diamond- tipped steel. Why is that so?

Accepted Answer

The modulus of elasticity of diamond is

Question 7

If a concrete test cylinder measuring 6 in. × 12 in. breaks when the load on it reaches 169.5 k, what is the compressive strength of concrete? Express the strength in psi.

Accepted Answer

Load, P = 169.5 k
Area on whic

Question 8

What are the units of stress in the U.S. system of units and the SI system of units?

Accepted Answer

In the U.S. customary system of units, w

Question 9

In a steel column that rests on a concrete footing, the area of the bearing plate used is generally

Accepted Answer

A) smaller than the cross- sectional area of the column. 
B) equal to the cross- sectional area of the column. 
C) greater than the cross- sectional area of the column. 
A) smaller than the cross- sectional area of the column. 
B) equal to the cross- sectional area of the column. 
C) greater than the cross- sectional area of the column.

Question 10

When a cable or rope is compressed by a force, what is the compressive stress in it?

Accepted Answer

A) Zero 
B) Infinite 
C) Equal to the force applied 
D) Force divided by the cross- sectional area of rope 
E) None of the above 
A) Zero 
B) Infinite 
C) Equal to the force applied 
D) Force divided by the cross- sectional area of rope 
E) None of the above

Question 11

In a typical stress- strain diagram of a material, the stress is generally plotted along the vertical axis.

Accepted Answer

A) True 
 B)False

Question 12

The unit of modulus of elasticity is

Accepted Answer

A) GPa. 
B) Pa. 
C) psi. 
D) ksi. 
E) all of the above. 
A) GPa. 
B) Pa. 
C) psi. 
D) ksi. 
E) all of the above.

Question 13

What is the relationship between a material's brittleness and its tensile strength?

Accepted Answer

A brittle material i

Question 14

A material that is weak in tension is

Accepted Answer

A) weak in bending. 
B) strong in bending. 
C) no relationship between the tensile and bending strengths of a material. 
A) weak in bending. 
B) strong in bending. 
C) no relationship between the tensile and bending strengths of a material.

Question 15

The stirrups in a reinforced concrete beam are used to

Accepted Answer

A) reduce the deflection of the beam. 
B) increase the strength of the beam in shear. 
C) increase the durability of the beam. 
D) increase the strength of the beam in bending. 
E) none of the above. 
A) reduce the deflection of the beam. 
B) increase the strength of the beam in shear. 
C) increase the durability of the beam. 
D) increase the strength of the beam in bending. 
E) none of the above.

Question 16

What is the shape and dimensions of the specimen typically used for determining the compressive strength of concrete?

Accepted Answer

A cylinder measuring

Question 17

Why do we use the term "bearing strength of soil" and not "compressive strength of soil" when, in reality, the soil is under compression from the load of the structure being supported?

Accepted Answer

The soil is under co

Question 18

A 20- ft- high column shortens by 0.6 in. under a load. What is the resulting strain in the column?

Accepted Answer

A) 0.0025 in. 
B) 0.0025 
C) 0.0020 
D) 0.0020 in. 
E) None of the above 
A) 0.0025 in. 
B) 0.0025 
C) 0.0020 
D) 0.0020 in. 
E) None of the above

Question 19

Explain the concept of safety margin in the design of structures.

Accepted Answer

Safety margin implies that the actual st

Question 20

Is low- carbon steel an elastic or a plastic material?

Accepted Answer

Low- carbon steel is elastic u

Exam 4: Load Resistance the Structural Properties of Materials

Explain what load factor is in structural design.

Explain the concept of buckling. Explain whether buckling would occur if a member is subjected to bending. What measures do we adopt to prevent the buckling failure of building components?

The test specimen used for determining the compressive strength of concrete in the United States is a

What is the unit of measure for strain?

Explain with the help of a sketch why a brittle material is weak in shear.

The saw blades used for cutting masonry, concrete and stone are made of diamond- tipped steel. Why is that so?

If a concrete test cylinder measuring 6 in. × 12 in. breaks when the load on it reaches 169.5 k, what is the compressive strength of concrete? Express the strength in psi.

What are the units of stress in the U.S. system of units and the SI system of units?

In a steel column that rests on a concrete footing, the area of the bearing plate used is generally

When a cable or rope is compressed by a force, what is the compressive stress in it?

In a typical stress- strain diagram of a material, the stress is generally plotted along the vertical axis.

The unit of modulus of elasticity is

What is the relationship between a material's brittleness and its tensile strength?

A material that is weak in tension is

The stirrups in a reinforced concrete beam are used to

What is the shape and dimensions of the specimen typically used for determining the compressive strength of concrete?

Why do we use the term "bearing strength of soil" and not "compressive strength of soil" when, in reality, the soil is under compression from the load of the structure being supported?

A 20- ft- high column shortens by 0.6 in. under a load. What is the resulting strain in the column?

Explain the concept of safety margin in the design of structures.

Is low- carbon steel an elastic or a plastic material?

An Overview of the Building Delivery Process How Buildings Come Into Being

Design and Constructions Regulations

Loads on Buildings

Properties of the Envelope-I Thermal Properties

Properties of the Envelope-II Air and Water Vapor Control

Fire and Smoke-Related Properties

Acoustical Properties of Materials

Principles of Joints and Sealants Expansion and Contraction Control

Principles of Sustainable Construction

Soils and Excavations

Below-Grade Construction Foundation Systems and Basements

Materials for Wood Construction-I Lumber

Materials for Wood Construction-Ii Engineered Wood Products, Fasteners, and Connectors

Wood Light-Frame Construction-I

Wood Light-Frame Construction-II

Structural Insulated Panel Construction

Material Steel and Steel Components

Structural Steel Construction

Cold-Formed Steel Construction

Lime, Portland Cement, and Concrete

Concrete Construction-I Formwork, Reinforcement, and Slabs-On-Ground

Concrete Construction-II Site-Cast and Precast Concrete Framing Systems

Masonry Materials-I Mortar and Brick

Masonry Materials-II Concrete Masonry Units, Natural Stone, and Glass Masonry Units

Masonry and Concrete Bearing Wall Construction

Exterior Wall Cladding-I Principles of Rainwater Infiltration Control

Exterior Wall Cladding-II Masonry, Precast Concrete, and Gfrc

Exterior Wall Cladding-III Stucco, Adhered Veneer, Eifs, Natural Stone, and Insulated Metal Panels

Glass, Glazing, and Light-Transmitting Plastics

Windows and Doors

Exterior Wall Cladding-Iv Wall System in Glass

Roofing-I Low-Slope Roofs

Roofing-I Steep Roofs

Stairs

Floor Coverings

Ceilings

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