Concrete Short Columns - Design Practices
A short concrete column used in freeway design
Short Column Criteria:
To check if a short column is present then the following conditions must be met. Otherwise check to see if you fit under the Concrete Long Column Design type procedure. Ideally, solving for a short column will be easier than a long column.
If the structure is part of a braced system then:
{kl_u\over{r}}\le 34-12{M_1\over{M_2}}\le 40
If the structure is part of a unbraced system then:
{kl_u\over{r}}\le 22
where:
k = the effective length factor (can be conservatively taken as 1.0 [1])
lu = clear height of the column
M1 = the smaller absolute value of the two end moments acting on the column
M2 = the larger absolute value of the two end moments acting on the column
r = radius of gyration
lu = clear height of the column
M1 = the smaller absolute value of the two end moments acting on the column
M2 = the larger absolute value of the two end moments acting on the column
r = radius of gyration
Concrete Short Column Analysis
Several methods for concrete short column design have been provided below including:
- Concrete Tied Columns
- Concrete Spiral Columns
- Concrete Column Design for Small Eccentricity
- Concrete Column Design for Large Eccentricity
- Concrete Column Interaction Diagrams
References:
- American Concrete Institute, "Building Code Requirements for Structural Concrete (ACI 318-05) and Commentary (ACI 318R-05)", 2005
- From Section 10.12.2