Structure:	3 pier caps & 14 columns of Iowa 192 viaduct
Location:	Council Bluffs, Iowa, USA
Project Date:	August 1998
Client:	Iowa Department of Transportation
Area Treated:	4973 ft2 (462 m2)
Contract Duration:	3 months
Contractor:	Vector Construction Inc.

Project Description:

Leaking construction joints at every third set of piers on the Iowa Department of Transportation's structure 7801.1S192 of Iowa 192 viaduct, became the source of chlorides that led to the contamination of 3 sets of piers including the pier caps and columns. As a result of this contamination, the Iowa DOT chose this substructure to be the first structure in the state to be treated with the NorcureŽ Chloride Removal System and to verify its viability as a more cost-effective alternative to conventional rehabilitation practices.

Project Solution:

The piers were repaired in the conventional way to eliminate the delaminated areas and spalling. Vector Construction Inc. performed the concrete repair work and the installation of the ECE system over a period of approximately 3 weeks. The substructure was then treated for a minimum time of 60 days. Tests were performed following the Electrochemical Chloride Extraction (ECE) process and the test results showed that on average in the 0-1" (0-25mm) range 79.3% of the chlorides were removed, in the 1-2" (25-50mm) range 65.2% were removed and in the 2-3" (50-75mm) range 48% were removed.

"The Concrete Restoration Specialists"The Iowa Department of Transportation was very satisfied with the test results and plan to use ECE treatment on the remainder of the substructure in the summer of 2000.