A chlorinated rubber coating over a red-lead primer was applied 

 to steel piling and the test specimens exposed in the surf of the outer 

 harbor at Port Hueneme, California. At the end of six months, the 

 coating rated relatively low as shown in Table III. 



A recent report (Alumbaugh and Brouillette, 1966) on tests including 

 16 synthetic rubber coating systems shows that 9 systems were considered 

 to have failed or to be on the brink of failure by the end of four years 

 exposure in seawater. Figure lib shows that System No. 11 which consisted 

 of a T7-mil thickness of flame-sprayed rubber powder gave steel the 

 longest protection of the synthetic rubber coatings. This system did 

 not fail until after approximately 11 years of exposure in seawater. A 

 17.5-iiiil coating system, consisting of a synthetic rubber primer and a 

 neoprene finish coat plus accelerator, gave the second best performance 

 of this generic group by protecting the steel for approximately 8 years. 



(k) Phenolics . A phenolic mastic coating was tested on steel 

 piling for 2 1/2 years (Alumbaugh, I962) and according to test results 

 as shown in Tables Ila and lib performed quite well with the exception of 

 Zone "B" which was in the lower part of the tide zone. Due to the depth 

 of the water. Zone B was also in the sand-abrasion zone. 



Phenolic mastic coatings were tested on mooring buoys for 5 years. 

 The ratings of the coating at the end of 2 years was good-fair (Drisko, 

 1965). See Table VIII. The coating rating was also good-fair after 5 

 years (Drisko, I968). 



A phenolic resin mastic coating applied to sheet and H piling driven 

 in the surf along the coast of the Marianas was reported to have per- 

 formed adequately in protecting the piling for k years (Bureau of Yards 

 and Docks, 1963). See Table VII. 



In other tests at Port Hueneme, California, phenolic coatings 

 performed better as a group than any other generic type (Alumbaugh and 

 Brouillette, I966). One phenolic mastic coating (System No. 72), given 

 in Figure lib, gave complete protection to steel for approximately 9 

 years. It was reported to be performing very well after 9 1/2 years 

 of exposure. The same coating was also reported to have given the best 

 performance on steel specimens subjected to the abrasive action of sand 

 in the surf at Port Hueneme (Alumbaugh and Brouillette, I966). 



(5) Saran . After 2 1/2 years of testing on steel piling, 

 a saran coating system rated quite good except in the sand-abrasion zone 

 (Alumbaugh, I962). Since saran was lower in cost than the other coating 

 systems tested for 2 1/2 years, it was recommended as the most economical 

 of the group to protect steel piling where sand abrasion does not exist. 

 See Tables Ila and lib. 



Saran was tested on mooring buoys by the U. S. Naval Civil Engineer- 

 ing Laboratory (Drisko, 1965 ) • Ratings at the end of approximately 2 years 



31 



