Title: In-situ Assessment of Durability of Concrete Motorway Bridges

Author(s): P. A. Muhammed Basheer, F. R. Montgomery and A. E.Long

Publication: Symposium Paper

Volume: 131

Issue:

Appears on pages(s): 305-320

Keywords: absorption; bridges (structures); concretes; corrosion; deterioration; durability; in situ test methods; permeability; strength; test; Materials Research

DOI: 10.14359/1215

Date: 3/1/1992

Abstract:
Assessment of durability of concrete motorway bridges in Northern Ireland is part of a program of collaborative research of the Civil Engineering Department with the Roads Services of the Department of Environment (Northern Ireland). This involves testing bridges on site to develop methods that can be used to investigate the condition of approximately 1300 reinforced concrete bridges in the province so that a planned maintenance scheme can be proposed. Describes results of comprehensive tests that were carried out on a severely delaminated motorway bridge both prior to and after repair. Five other motorway bridges that represent the general population in terms of age, construction form, and past maintenance were also tested and the results compared. It has been observed that concrete strength is not a reliable index of proneness to deterioration, but permeability results allied to the knowledge of exposure to salt are more likely to provide a useful guide to durability. The in situ tests for sorptivity indicated that, with the two silane-treated bridges, one keeps the moisture out, whereas the other fails to do so. High-permeability concrete combined with leaking expansion joints have been found to be the main cause of absorption of chloride and the corrosion of steel.