Concrete Beam Economics. Bob Lawrence Alan Schuetz James Giancaspro Mark McDonnell. Agenda. Problem Statement Concrete Assumptions Example of Spreadsheet Program Economics of a Concrete Beam Alternative Solutions Concrete Steel Economic Assumptions for Concrete and Steel
Water, Sand, Aggregate and Steel will have constant unit prices.
The price of water came from the Seattle Public Works.
The prices for Sand, Steel and Aggregate were taken from Engineering News Report.
The unit prices for Sand, Aggregate and Steel are calculated through a 20 city average.Economic Assumptions Concrete
Concrete Beams have a life span of 50 years
Labor cost will be the same for all 3 types
Concrete beams require negligible maintenance
At the end of 50 years the beam has no salvage value and is recycledConcrete Economic Assumptions Cont.
Installation cost for steel and concrete beams are the same
When disassembled neither will have an effect on the environment so that will not be considered.
Assume 3 Masons can construct a concrete beam in 1 hour (pre-molded)Assumptions for Concrete/Steel Comparison
We will terminate our economic comparison at 49 years so the study times will be equal
The spreadsheet program assumes all steel is 60 ksi.
The price of steel is a national average.
The current recycling value of steel is $90.00/tonAssumptions Cont.
W36 - 848
W36 - 798