CORROSION OF ALUMINUM CONDUIT IN CONCRETE

CRACKS HAVE DEVELOPED IN THE REINFORCED CONCRETE OF SEVERAL BUILDINGS DUE TO CORROSION OF ALUMINUM CONDUIT, AND, IN EVERY CASE INVESTIGATED, IT WAS FOUND THAT CALCIUM CHLORIDE HAD BEEN USED IN THE CONCRETE MIX. STUDIES DEMONSTRATE THAT RELATIVELY LARGE GALVANIC CURRENTS ARE GENERATED IF ALUMINUM AND STEEL ARE IN ELECTRICAL CONTACT WHEN EMBEDDED IN CONCRETE CONTAINING CALCIUM CHLORIDE. THESE CURRENTS MAY LEAD TO SUFFICIENT CORROSION OF THE ALUMINUM TO CAUSE COLLAPSE OF THE CONDUIT OR CRACKING OF THE SURROUNDING CONCRETE. LABORATORY TESTS HAVE INDICATED THAT SOME COATINGS ARE EFFECTIVE IN PROTECTING THE ALUMINUM CONDUIT UNDER SUCH CONDITIONS. THE EMBEDMENT OF UNCOATED ALUMINUM CONDUIT IN REINFORCED CONCRETE CONTAINING APPRECIABLE AMOUNTS OF CALCIUM CHLORIDE OR SODIUM CHLORIDE SHOULD BE AVOIDED. /PCA/

• Authors:
  • Monfore, G E
  • Ost, B
• Publication Date: 0

Media Info

• Serial:
  • Portland Cement Assoc R & D Lab Bull
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Aluminum; Calcium chloride; Concrete; Conduits; Corrosion; Cracking; Galvanic corrosion; Protective coatings; Reinforced concrete
• Uncontrolled Terms: Concrete cracking
• Subject Areas: Highways; Materials;

Filing Info

• Accession Number: 00213611
• Record Type: Publication
• Source Agency: Portland Cement Association
• Report/Paper Numbers: No 173
• Files: TRIS
• Created Date: Jun 1 1970 12:00AM