Title: Field Exposure of Concrete to Severe Natural Weathering

Author(s): Joseph F. Lamond and M. K. Lee

Publication: Symposium Paper

Volume: 122

Issue:

Appears on pages(s): 201-216

Keywords: air-entrained concretes; concrete durability; deterioration; exposure; field tests; freeze-thaw durability; marine atmospheres; sea water; weathering; General

DOI: 10.14359/3739

Date: 6/1/1990

Abstract:
The ultimate test of concrete durability to natural weathering is how it performs in the environment in which it is to serve. Laboratory testing yields valuable indications of service life and durability. However, the potential disrupting influences in nature are so numerous and variable that actual field exposures are highly desirable to assess the durability of concrete exposed to natural weathering The U.S. Army Corps of Engineers, through the Waterways Experiment Station, Structures Laboratory, maintains a natural weathering exposure station. It is located on Treat Island in Cobscook Bay near Eastport, Maine. This station has been in use since 1936 and is an ideal location for exposure tests, providing twice-daily tide reversals and severe winters. The average tidal range is about 18 ft (5.4 m) with a maximum of 28 ft (8.5 m) and a minimum of 13 ft (4 m). In the winter, the combined effect of air and water temperatures creates a condition at meantide where specimens are repeatedly thawed and frozen. There have been 23 completed investigations and many of these have been previously reported. There are currently 40 active investigations. Four of these investigations are briefly discussed in this paper.