(3) Concrete . The cement, sand, and stone required to make 

 concrete are available in all parts of the United States. Some of the 

 smaller Pacific Islands may require the importation of cement. 



(4) Wood. Wood used to be one of the most available construction 

 materials in the United States. It is generally produced within reasonable 

 shipping range of a coastal project. Now, certain types and sizes of 

 hardwoods are becoming more difficult to obtain. In cases where the 

 designer would almost automatically select wood, he now has to compare wood 

 to the relative costs and advantages of other construction materials. 



(5) Asphalt . Asphalt is generally available in the United States 

 but may not be available for project's in other areas due to either lack of 

 the material or lack of handling equipment. 



(6) Synthetics . Synthetics are a manufactured material, and the 

 location of the plants may not be near the construction site. However, 

 they are easily and economically shipped. There may be a timing problem as 

 some lead time, particularly for large orders, may be required for delivery. 



b. Transportability . 



(1) Transport Mode . Most construction materials for coastal 

 projects can be transported by conventional freight haulers, i.e., rail, 

 truck, barge, or ship. Armor stone for breakwaters and jetties may have 

 transport problems due to their large dimensions and extreme weight. The 

 design size of armor stone is frequently from 89 to 267 kilonewtons (10 to 

 30 tons) per stone. Most State highway departments have a load limit of 

 178 to 214 kilonewtons (20 to 24 tons) per truck. This is not a problem 

 with rail or barge haul but most coastal projects require some use of 

 public highways. This load limitation not only limits the design size of 

 the armor rock, but also requires careful load scheduling to maximize the 

 use of either trucks or railway cars. 



(2) Handling Limitations . Coastal projects in isolated locations 

 must be carefully analyzed so that materials selected are capable of being 

 handled by available equipment. This not only involves placement equipment, 

 but transport and processing equipment. 



(a) Stone . The primary problem with stone is the handling of 

 armor stone. Quarry processing and loading equipment usually has greater 

 capability to handle large armor stone than public highways will permit. 

 The placement of armor stone on breakwaters and jetties not only requires a 

 certain tonnage lift capability, but the equipment must be able to reach 

 outward a sufficient distance to accurately place the toe rock. 



(b) Earth . Earth can generally be handled with conventional 

 construction equipment. The availability of compaction equipment may control 

 the method by which an earthfill is compacted. 



(c) Concrete. Many special designs of concrete structures may 

 require highly specialized handling equipment. The costs or availability of 

 such equipment may influence the selection of a concrete structure. Under- 

 water placement, the shaping of concrete armor units such as tribars and 



