recommended to avoid sharp corners by making rounded contours and the 

 use of fillets. 



Maintenance . Scheduled (preventive) maintenance will include such 

 items as removal of fouling and replacement of coatings, if used. Un- 

 scheduled (corrective) maintenance will be due to unanticipated loadings 

 or material behavior. 



Repair . Two types of repair are envisioned. One type is repairing 

 sections of concrete having corrosion of steel reinforcement and the 

 other type is repairing damaged sections of the structure caused by im- 

 pact or overload. Both types of repair are not well-developed; however, 

 approaches to the problem are available. Remedial measures for corrosion 

 include (1) cathodic protection, (2) repair of spalled and laminated con- 

 crete, and (3) isolation from the environment by coatings on the steel or 

 by coating the exterior surface of the concrete. L^J The recommended ap- 

 proach is to remove all concrete covering the first layer of reinforcement 

 and replace this concrete after appropriate cleaning and preparation. L? J 

 A new approach with much promise is polymer impregnation of existing 

 concrete. Corrosion can be terminated at whatever stage of damage it has 

 caused by using polymer-strengthened concrete technology. Polymer im- 

 pregnation of deteriorated concrete has been applied to bridge decks as 

 an experimental method. The same techniques could be applied to concrete 

 in marine structures. The result would be a stronger concrete than the 

 original material and an impervious concrete that would prevent oxygen 

 and chloride ions from reaching the steel. This same technique could be 

 used as a preventive system; however, the cost of polymer-strengthened 



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