Assignment #2r
contact | homepage | spring 2008 index for ARCH 264/564 | current index for ARCH 264/564 | homework index | textIssued Mar. 4, 2008.
Due: Mar. 6, 2008 (not collected or graded)
1. Reinforced concrete columns: analysis
What is the maximum design (factored) load, Pu, that can be supported on the following reinforced concrete columns? Use f'c = 5 ksi; and fy = 60 ksi. Check reinforcement ratio and bar fit:
a) 16" x 20" tied column with 4 No. 18 bars.
b) 20"-diameter spiral column with 10 No. 10 bars.
2. Reinforced concrete columns: design
Select steel bars for a 16" x 16" first-floor tied column. Assume that the dead load consists only of 8"-thick floor and roof slabs (weighing 150 pcf); and that the live load (with no live load reduction needed) is 100 psf on all floors, but not the roof. Use f'c = 4 ksi; and fy = 60 ksi. Check reinforcement ratio and bar fit.
3. Reinforced concrete columns: design
Assuming a reinforcement ratio of about 0.04 (i.e., 4%), how big would a round spiral column be that must support a design (factored) load, Pu = 1000 kips*. Round diameter to the closest even inch. Use f'c = 4 ksi; and fy = 60 ksi. Do not find steel area or select bars.
* Note that "design" or "factored" loads, Pu, already include the load factors. That is, they already are in the form: 1.2D + 1.6L.
© 2008 Jonathan Ochshorn. First posted 3 March 2008. Last updated: 03 March 2008