Bricks, hollow concrete blocks, and cinder blocks have been used as 

 temporary repair materials; however, they generally break down during han- 

 dling and are not of much long-term value. Also they have no value as an 

 underlayer or armor layer. 



Salvaged ships and barges have been used as temporary breakwaters by 

 manuevering them into a selected location, sinking them and then filling them 

 with rock or gravel to provide stability. Removing these devices when a 

 permanent structure is desired or upon their disintegration, is usually a 

 difficult problem. Other salvaged materials such as railroad cars and auto- 

 mobile bodies have been used in bank or shore protection, however, they are 

 not satisfactory and are usually unsightly and hazardous if located where 

 people may visit. Used rubber tires have a variety of uses such as fenders 

 on barges, work boats and docks. They have also been successful as floating 

 breakwaters to protect basins against short-period waves. Several different 

 arrangements have been model tested. Flotation has been created by filling 

 tires with urethane foam. If anchored in place or on the bottom, tires have 

 served as a revetment and to slow the bed movement of littoral drift. 



i . Protective Systems . 



(1] General. Protective systems are applicable to steel and alloys; 

 wood, and concrete, usually for esthetic reasons or, in some few cases, to 

 decrease water penetration into relatively porous concrete. Protective 

 systems are classified in two categories; coating and cathodic protection. 

 Each of these systems may be used separately, but in many instances cathodic 

 protection can be successfully used to supplement coating systems. 



(2) Coatings. Protective coatings range from mere decorative 

 paints to complex and multicoat systems requiring careful surface prepara- 

 tion, proper coating application techniques, and the careful selection of 

 coating systems. In the consideration of a coating requirement, the first 

 step is to consider the type and kind of surface to be protected, i.e., 

 wood, concrete, steel or other metals and alloys. Next consider the environ- 

 ment the structure surface is exposed to, such as a marine atmosphere, a tide 

 or splash zone or a submerged zone in either fresh or salt water. With this 

 information and other specific data as set forth in Section XI, the coastal 

 engineer may then consider the generic category as well as the specific type 

 of coating within a category that is best suited for the protection of a 

 given structure. 



The types of coatings and their generic classifications are discussed in 

 Section XI. To adequately evaluate a coating's protection performance it is 

 necessary to consider the properties of the coating material, the surface 

 preparation requirements, and the application procedure as well as the 

 drying or curing processes. To aid evaluation, Section XI discusses the 

 surface preparation processes including resulting metal surface anchor 

 patterns, the number of coats and thickness, and the drying or curing pro- 

 cesses necessary to obtain a good coating system that can be expected to 

 properly protect a structure. Coatings are applied by brush, roller, spray 

 (both air and airless), and dipping. 



Coating repair is a common procedure; however, there are precautions that 

 must be taken to ensure successful repair. Coating compatibility is a must 



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