elements with less time and complexity than present methods. For example, 

 polymer concrete and sulphur concrete may permit high strength joints to 

 be made in the field in the time period of hours. 



3 # Develop methods to assemble large floating structural components. 

 The completed structure may be assembled from components that were built 

 at different locations. The components, which are major structures them- 

 selves, will be assembled while floating. An advantage to this approach 

 is that the components may be built in relatively shallow water which 

 makes available more construction sites. The assembly technique should 

 be reversible to provide for replacement of modules as discussed in the 

 "Requirements" section. 



Prestressing Systems . Development of a noncorrodible prestressing 

 system would improve the overall reliability of the structure during long-term 

 exposure to the ocean environment. Highly stressed steel of rather small 

 diameter is vulnerable to corrosion and subsequent failure of the steel 

 tendon. Synthetics, such as the new Kevlar fibers, and ceramics should be 

 investigated for prestressing materials for concrete. Of particular in- 

 terest are the failure mode and whether or not such materials undergo creep 

 or progressive failure under long-term sustained loads. The economic and 

 technical feasibility of using noncorroding metals and alloys, such as 

 titanium, should also be studied. 



Out-of-Roundness Measurements . Methods to measure out-of-roundness 

 of full-scale structures need to be developed. The structural capacity of 

 pressure-resistant concrete hulls is dependent on the out-of-roundness 

 deviations from true circular form. Designs are based on a specified 



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