Title: Study of Reinforced Concrete Beams Exposed to Marine Environment

Author(s): Edward F. O'Neil

Publication: Symposium Paper

Volume: 65

Issue:

Appears on pages(s): 113-132

Keywords: beams (supports); bond (concrete to reinforcement); chlorides; concrete durability; corrosion; cracking (fracturing); crack width and spacing; deterioration; exposure; flexural strength; freeze-thaw durability; marine atmospheres; reinforced concrete.

DOI: 10.14359/6350

Date: 8/1/1980

Abstract:
A study was begun in 1950 to determine the effects of severe natural weathering to stressed, reinforced concrete beams of various compositions and degrees of stress. The objectives of the study were to obtain information on the long-term weathering of air-entrained and non-air-entrained concrete beams containing steels of different compositions, types of deformation, and different levels of stress. The beams were placed on the beach at the natural weathering exposure station on the south side of Treat Island, Cobscock Bay, Eastport, and Lubec in Maine. The beams were subjected to twice daily tidal cycles and, during the winter months, to cycles of freezing and thawing. The beams were inspected annually during the exposure period and evaluated by a team of inspectors rating the degree of deterioration. Maximum crack widths were measured each year from 1956 to 1975 when the exposure period was concluded. Thirteen of the 82 beams that were originally placed remained in 1975 and 11 were returned to the laboratory for testing. The results of the exposure study, the laboratory investigation, and other findings are discussed in this paper.