concrete design
- True or false: ACI only permits tension-controlled failure modes in columns.
- What is the φ factor for a spiral column?
- Name the 4 principles used to calculate the strength of a column.
- How do the equilibrium equations for a column have to be adjusted compared to the equilibrium equations for a beam?
- In addition to axial load and the primary bending moments from the applied loads, what other effect must long (slender) columns be designed for?
- How does ACI classify a column as long or short?
- In a short column, what factors control the maximum load supported?
- Describe what causes the secondary P-Δ moment in a long column.
- Name three types of columns.
- Describe a composite column.
- True or false: ties increase the strength of a column.
- Are tied or spiral columns better for earthquake-prone areas?
- Why is the failure mode of a spiral column more ductile than the failure mode of a tied column?
- What is the equation for axial load capacity of a reinforced column?
- Why is the capacity reduction factor φ smaller for a column than for a beam?
- Why does the ACI Code limit the design capacity of an axially loaded column to 80 or 85 percent of its actual strength?
- What are the maximum and minimum percentages of steel that ACI permits a column to be reinforced with?
- From a practical standpoint, what is the minimum possible column dimension?
- What is the smallest size tie permitted by the ACI Code for the column shown? What would be the required spacing of those ties?
- True or false: the confining effect of spiral reinforcement causes the concrete compressive strength to increase.
- Define plastic centroid.
- When is the column capacity reached (i.e. when does failure occur)?
- True or false: Columns with axial load plus bending moment can have one side of the column cross section in tension and one side in compression.
- True or false: Columns with axial load plus bending moment can have all of the column cross section in compression.
- What is an interaction diagram?
