CORROSION TAKES ITS TOLL ON TAY

Seawater chloride attack on the reinforcements of the eighteen year old concrete piers of the Tay Road Bridge is thought to be the most likely cause of deterioration. The decay is worst in the splash zones, but many of the deck expansion joints are leaking, leading to corrosion over the full column in places. Although inspection is difficult because of the failure of the railed gantry system, it appears that the 100 mm concrete cover layer has separated from the expanding reinforcement cage. Case tests show good concrete strengths but the cover is down to 20 mm in places. It is possible that sea water could have entered through early cracking, but data on previous bridge inspections are lacking. The worst spalling is generally above the deeper water and as three severe winters have produced ice flows, impact damage has not been ruled out. Remedial works could prove difficult -trials with epoxy resin patching have failed. More detailed tests are planned when concrete jackets will be built around some columns. It is also hoped to replace the faulty inspection system with one which will include a platform to reach down the entire pier. (TRRL)

Media Info

  • Features: Photos;
  • Pagination: p. 33
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00394569
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: Jul 31 1985 12:00AM