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
http://www.worldstainless.org/Files/issf/non-image-files/PDF/Life_Cycle_Costing_Report_from_Sorbonne_University.pdf (Page 39)

Picture by Wandervogel (Own work) via Wikimedia Commons