Rubber tires are used to make floating breakwaters capable of attenuating 

 short-period waves. Salvaged ships and barges should not be used as break- 

 waters in the ocean or large lakes and have limited use as a type of caisson 

 in that they are generally located at a remote station and towed to the site 

 where they are sunk and perhaps filled with sand or rock to serve as break- 

 waters or reefs. 



(2) Reefs . In addition to barges, automobile and railroad car 

 bodies, broken concrete and rubber tires can be formed to trap sand for 

 beach contouring and to encourage the growth of marine biota. Broken 

 asphaltic cement, concrete blocks and bricks can all be used to create 

 rubble-mound reefs. Below the wave and breaker zone such materials are more 

 durable and more likely to serve successfully. 



c. Shore-Connected Structures . 



(1) Breakwaters, Jetties, and Groins . Salvaged concrete, broken 

 asphalt cement, concrete blocks, bricks, salvaged ships and barges, salvaged 

 railroad car bodies, and automobiles can be used as discussed for offshore 

 structures but they all have severe limitations. 



(2) Seawalls and Bulkheads . Toe protection and backfill materials, 

 where rock would normally be used, can be of salvaged concrete, asphaltic 

 cement, concrete blocks or brick. These materials could also serve as 

 aggregate for preplaced aggregate concrete. 



(3) Revetments . All the materials discussed in this section 

 except the ships, barges and car bodies can be used to stabilize revetments. 

 The finer particles of crushed materials would be suitable for filter 

 blankets, the rest as rubble or cover material. 



(4) Piers and Wharves . Salvaged rubber tires make good bumpers 

 and fenders for small craft using the piers and wharves. Tires are also 

 good buffers between independent floats or structures that might otherwise 

 bump or scuff each other in moving with tides, waves or currents. 



Broken concrete, asphaltic concrete and broken concrete blocks or 

 bricks can be used as revetment to protect the shoreside embankment of 

 piers or wharves. 



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