FUTURE OF CONCRETE OFFSHORE STRUCTURES.

For structures which are to be permanently moored or grounded on the seabed, the attractions of concrete, particularly prestressed concrete, are well-known. For all types of device it has been found that the capital investment is immense, considerably more so than for fossil fuel or nuclear options, and that the major part of the cost relates to the civil works. It is natural, therefore, that the design life of such structures should be extensive, with sights set on 100 years rather than the 30-year design life of conventional generating stations. The following factors are of prime importance in such plans: 1. Long-term durability based upon proven materials technology. 2. Good seakeeping qualities in the expected environment. 3. Proven foundation performance for seabed based structures. 4. Proven techniques for towing, installation and mooring. 5. Ease of regular maintenance and ability to repair if damaged.