be considered. These loading conditions cover the topic of punching 

 shear failure. Methods that quantify the strain energy absorption of 

 concrete need to be proposed and studies conducted to verify the theories. 



Design for Fatigue . Guides to design for fatigue in an ocean environ- 

 ment need to be developed. Tests should be conducted on reinforced and 

 prestressed concrete members that are saturated with seawater and remain 

 submerged during test. Initial tests should explore differences between 

 on-land and in-seawater fatigue behavior for concrete. 



Construction 



Construction Methods . A comprehensive study should be conducted on 

 construction methods. No other item can result in as significant a cost 

 saving for the structure as improvements in the method of construction. 

 Innovations and developments in this field usually evolve by building 

 many of a certain kind of structure and from competition. Research and 

 development has the potential of by-passing some of this evolution. 



Significant advances in construction methods are possible. For 

 example, the following items are highlighted: 



1. Develop methods to utilize more precast elements in construction. 

 Precast elements can be built by many subcontractors, and with proper 



timing, the elements only have to be assembled at the construction site. 

 The objective is to minimize steel work and cast-in-place concrete at the 

 job site. Innovative techniques might show that precast segments combined 

 with slip-forming methods for the joints will increase the speed of con- 

 struction over that of an entire slip-formed operation. 



2. Develop improved joining methods for precast elements. New types of 

 concretes and synthetic materials open the possibility for joining precast 



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