Schaffhausen bridge
The Schaffhausen bridge across the river Rhine was completed in 1995. The bridge is required to resist to atmospheric corrosion and de-icing salts. The bridge is expected to last 80 years without loss of structural integrity and without significant maintenance.
Three options were considered for the rebar reinforcement:
- Carbon steel: expensive repairs would have been required every 25 yars and caused heavy traffic disruption
- Epoxy coated carbon steel: less extensive repairs would nevertheless have to be carried out every 25 years with reduced traffic disruption
- Carbon steel with stainless steel in the critical areas: meets the design life requirements
The comparative costs of the three alternatives are shown below.
Proper use of stainless steel leads to an extra cost of only 0.5%, paid back 30 times by the savings achieved over the lifetime of the bridge!
LIFE CYCLE COST SUMMARY OF A RIVER CROSSING HIGHWAY BRIDGE:
|
Description |
Carbon Steel |
Epoxy C.S. |
Stainless Steel |
|
Material costs Fabrication costs Other installation costs |
8,197 0 15,611,354 |
31,420 0 15,611,354 |
88,646 0 15,611,354 |
|
Initial cost (CHF) |
15,619,551 |
15,642,774 |
15,700,000 |
|
Maintenance Replacement Lost production Material related |
0 256,239 2,218,524 0 |
0 76,872 2,218,524 0 |
0 -141 0 0 |
|
Operating costs (CHF) |
2,474,763 |
2,295,396 |
-141 |
|
Total LCC (CHF) |
18,094,314 |
17,938,170 |
15,699,859 |
References:
http://www.concretebookshop.com/tr51-guidance-on-the-use-of-stainless-steel-reinforcement-1821-p.asp
Picture by Wandervogel (Own work) via Wikimedia Commons