Prestressing technology

Significant advances have been made in the technology of CP of prestressed concrete components through extensive fundamental research and evaluation of CP systems that have been installed. Concerns about a loss of bond between... 

B. E. Eakin, W. G. Bair, J. J. Closner, and R. Maroti, Below Ground Storage of Liquefied Natural Gas in Prestressed Concrete Tanks, Report No. 8 Institute of Gas Technology, American Gas Association, Chicago, Illinois (1963). 

The use of prestressed concrete vessels for gas-cooled reactors was initiated in Europe. A summary of reactor vessel designs using prestressed concrete technology is shown in Fig. 7. As indicated, vessels having... 

Development work for prestressed concrete reactor structures has been proceeding in the United States for the past several years. A wide background was already in existence in this country on prestressed concrete technology related to large tanks and beam structures. Two scale models of such reactor pressure vessels have been tested at General Atomic as part of a USAEC program for High-Temperature Gas-Cooled Reactors. 

Therefore the designer must allow for the various techniques for accomplishing the compressive prestress while allowing the flexibility of the supplier to apply their specialized technology. 

YuJ. Tokarev, 04. Sokolov, S.A. Skvortsov, A.M. Sidorov and L.V. Krause, A Boiling Water Reactor in a Prestressed Reinforced Concrete Vessel for an Atomic Central Heating-and-Power Plant, Nuclear Technology, Vol. 38, 1978 mid-April, pp. 221-224. 

The BWR 90 design is characterized by the use of internal recirculation pumps, fine motion control rod drives, a prestressed concrete containment, and extensive redundancy and separation of safety-related systems in the same way as the BWR 75 design that was developed in the 1970s. The modifications are mostly moderate and they have been made to adapt to updating technologies, new safety requirements and to achieve cost savings. 

Quantrill, R. J. and Hollaway, L. C. (1998), The flexural rehabilitation of reinforced concrete beams by the use of prestressed advanced composite plates . Composites Science and Technology, Vol. 58, pp. 1259-1275. 

The problems of interface in concrete elements, with classic reinforcement in the form of steel bars and prestressing tendons, are not considered here because they exceed the scope of this book and are widely examined in the manuals on concrete technology and concrete structures. 

Bangash, M.Y.H. The Automated three-dimensional cracking analysis of prestressed concrete vessels, Proc. 6 Int. Conf. Struct. Mech. Reactor Technology. Paper H3/2 Paris 1981... 

CEC and BAM Proceedings of the First International Conference on Structural Mechanics in Reactor Technology, 20-24, Berlin, Vol. 4, Reactor Pressure Vessels Part H Prestressed Concrete Pressure Vessels . Papers H3/4-H5/8, 1971. 

Bender M. A status report on prestressed concrete reactor vessels, pressure vessel technology. Nuclear structural engineering. Vols. 1, 2, 1965, pp. 83-90, pp. 206-223. 

CEC and Transactions of the Third International Conference on Structural Mechanics in Reactor Technology, 1-5, London, Vol. 3, Reactor VesselsPart H. Structural Analysis of Prestressed Concrete Reactor Pressure Vessels, 1975. 

The technology of cathodic protection of reinforced concrete is to elaborate its own protection criteria, other than for steel structures corroding in different environments than concrete. They are still mainly potential criteria, used carefully so as not to lead to overprotection and as a consequence liberation of hydrogen and weakening of the adhesion of concrete to steel. In prestressed structures, the presence of hydrogen can lead to embrittlement. John and Messham (1989) exhaustively describe the following protection criteria of reinforced concrete ... 

The birth of very high compressive strength concrete with low brittleness from appropriate simple technology would open the new era of constructional engineering, in which the prestressed concrete structure may be completitive with steel structure in strength/weight ratio. 

As of now, AWWA is nearing publication of a standard on CFRP Renewal and Strengthening of Prestressed Concrete Cylinder Pipe (PCCP) (now designated as ANSFAWWA CFRP). This standard has been in development since late 2009 and is intended to provide a consensus document that refleets the state of technology for material selection, design, installation, and QA/QC of the CFRP renewal and strengthening of PCCP. 

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