Unclassified 



SECURITY CLASSIFIC* 



20. Continued 



retrieved from tfie ocean for laboratory testing. Data on concrete compressive strength 

 gain, short-term implosion strength of the three retrieved spheres, and permeability and 

 durability of the concrete were obtained. This report summarizes the findings from the 

 laboratory and ocean tests. 



Library Card 



Civil Engineering Laboratory 



LONG-TERM, DEEP-OCEAN TEST OF CONCRETE 



SPHERICAL STRUCTURES - Results After 6 Years, by 



Harvey H, Haynes and Roy S. Highberg 



TR-869 51ppillus January 1979 Unclassified 



1 . Undersea concrete structures 2. Concrete spheres L 3.1610-1 



In 1971 , a long-term, deep-ocean test was started on eighteen concrete spheres, 66 inches 

 (1,676 mm) in outside diameter by 4.12 inches (105 mm) in wall thickness. The spheres were 

 placed in the ocean at depths from 1,840 to 5,075 feet (560 to 1,547 m). Over a 6.4-year period, 

 yearly inspections of the spheres by submersibles have provided data on time-dependent failure 

 and permeability. After 5.3 years, three of the spheres were retrieved from the ocean for 

 laboratory testing. Data on concrete compressive strength gain, short-term implosion strength 

 of the three retrieved spheres, and permeability and durability of the concrete were obtained. 

 This report summarizes the findings from the laboratory and ocean tests. 



Unclassified 



