Title: Deterioration in a Rehabilitated Prestressed Concrete Bridge

Author(s): Toshitaki Ohta, Koji Sakai, Minoru Obi, and Sadamu Ono

Publication: Materials Journal

Volume: 89

Issue: 4

Appears on pages(s): 328-336

Keywords: bridges (structures); corrosion; cracking (fracturing); deterioration; load tests; nondestructive tests; prestressed concrete; rehabilitation; reinforcing steels; Materials Research

DOI: 10.14359/2551

Date: 7/1/1992

Abstract:
Presents the results of various investigations, nondestructive tests, and loading tests on a rehabilitated prestressed concrete bridge in the thirty-second year since its construction and in the thirteenth year after being rehabilitated. The major causes of deterioration in the bridge may be attributed to the cracks which occurred along the sheaths because of freezing water inside the sheaths, caused by the incomplete filling of grout. The investigation revealed that although the rehabilitation with FRP and steel plate was effective against permeation of salt, the salt absorbed before rehabilitation steadily promoted the progress of corrosion of steel. The estimate of concrete compressive strength by newly developed measuring equipment gave relatively good correlation with the compressive strength test results. The measurement of half-cell potential showed relatively well the state of corrosion of the steel in concrete. The contribution of FRP and steel plate to the load-carrying capacity was small compared with the degree expected immediately after rehabilitation.