Corporate|Sitemap|Contact
Partial List of Publications

1. "The Additional Deflection of a Cantilever Due to the Elasticity of the Support," by W. J. O'Donnell, Journal of Applied Mechanics, Vol. 27, p. 461, September 1960.
A beam is cantilevered from a semi-infinite solid with neutral axis normal to its bounding plane (Two-dimensional problem). Deformation of the supporting solid allows the beam to rotate about the built-in end, producing a deflection in addition to that caused by bending and shear in the beam itself. Results of tests designed to measure this additional deflection are presented and compared with various theoretical values. Calculated deflections, based on classical bending and shear-deflection theory, are also compared with measured deflections. An experimentally verified expression for the additional deflection of a cantilever due to the elasticity of the support is given.

2. "An Analysis of Average Stress Intensities in Steam Generator Tube Sheet Ligaments," by W. J. O'Donnell, Bettis Technical Review, No. 21, p. 79, November 1960.
An analysis of stress intensities (shear stresses) is the minimum ligament sections of steam generator tube sheets is presented. This analysis can be used to evaluate the ligament stress intensities based on stresses averaged across the minimum ligament sections and averaged through the depth of the tube sheet. Both of these values are limited by the "Design Basis". The analysis is quite general and can be used for any biaxiality condition of the stress field in the equivalent solid plate and for any ligament orientation in the stress field; the analytical results are simplified and presented in a form suitable for design calulations.

3. "The Effect of the Tubes on Stresses and Deflections in U-Tube Steam Generator Tube Sheets," by W. J. O'Donnell, Bettis Technical Review, No. 21, p. 89, November 1960.
The results of tests run on an actual steam generator tube sheet are used to evaluate the effect of rolled-in tubes on stresses and deflections in the perforated portion of the tube sheet. Measured ligament strains are compared with theoretical values calculated for two cases: (1) assuming that the rolled-in tubes contribute no support to the tube sheet, and (2) assuming that the entire thickness of the rolled-in tubes is effective in stiffening the tube sheet and reducing ligament strains. Strain values calculated for Case No. 1 are found to average more than 75% higher than measured strains, and strain values are calculated for Case No. 2 are found to agree with average measured values within about 5%. It is concluded that the tubes contribute substantial support to tube sheets, and this support should be included in design calculations by taking the ID of the as-rolled tubes as the diameter of the perforations.

4. "Effective Elastic Constants for Steam Generator Tube Sheets," by W. J. O'Donnell, Bettis Technical Review, No. 22, p. 1, March 1961.
For purposes of analysis, perforated materials such as steam generator tube sheets are treated as solid materials having appropriate effective elastic constants (poisson ratio and elastic modulus). The values of these effective elastic constants differ for plane stress (in-plane) and bending loads, are dependent on the direction of the load with respect to the hole pattern as well as the ligament efficiency of the tube sheet. The significance of these variations and their effect on calculated pressure and thermal stresses in the tube sheet and shell of a steam generator are examined. A single set of effective elastic constants applicable to both plane stress and bending loads on the tube sheet is presented. These constants can be used in the entire range of practical steam generator tube sheet dimensions and depend only on the ligament efficiency of the tube sheet.

5. "Analysis of Perforated Plates," by W. J. O'Donnell, Doctoral Thesis, University of Pittsburgh (1962).

6. "Design of Perforated Plates," by W. J. O'Donnell and B. F. Langer, Journal of Engineering for Industry, Transactions ASME, Vol. 84, p. 307, August 1962.
This paper describes a method for calculating stresses and deflections in perforated plates with a triangular penetration pattern. This method is based partly on theory and partly on experiment. Average ligament stresses are obtained from purely theoretical considerations but effective elastic constants and peak stresses are derived from strain measurements and photoelastic tests. Acceptable limits for pressure stresses and thermal stresses in heat exchanger tube sheets are also proposed.

7. "Stresses and Deflections in Built-in Beams," by W. J. O'Donnell, Series B, Transactions ASME, Vol. 85, p. 265, August 1963..

8. "The Fatigue Strength of Members Containing Cracks," by W. J. O'Donnell, ASME Transactions, Journal of Engineering for Industry, Vol. 86, No. 2, May 1964.
The significant loss of fatigue life due to the presence of a crack, crack-like defect, or sharp notch is predicted herein from theoretical considerations. Strength reduction factors are given as a function of the crack depth, section width and type of loading. These values are applicable where defects of a particular depth are known to exist or where defects of a limited depth could exist without being detected. Although these values apply specifically to 100,000 psi tensile strength steels, they are conservatively high for lower strength steels, aluminum, and other materials which are less sensitive to notches. The results of this paper indicate that cracks in finite width members may produce a greater loss of fatigue life than previous theoretical work for members of infinite width had indicated.

9. "Fatigue Design Basis for Zircaloy Components," by W. J. O'Donnell, B. F. Langer, Nuclear Science & Engineering, Vol. 20, 1964
General methods have recently been developed for low cycle fatigue design. The required basic strain-controlled data for both non-irradiated and irradiated Zircaloy-2, -3, -4 were obtained for temperature between 70 F and 600 F. Data include both rolled and base-annealed material, and as-welded material tested in various directions. The cyclic stress-strain properties of these materials were also obtained and were found to differ quite significantly from the conventional properties. Using the cyclic properties in a Modified Goodman Diagram, fatigue-failure curves were developed which included the deleterious effect of the maximum possible mean stress that can exist in the material as it is cycled. Limited available test data confirm the validity of this test method. Using the resulting curves, one need only consider the cyclic stress loads. The worst possible effects of residual stresses due to welding and other fabrication methods, and mean stresses due to differential thermal expansion are included in the curves. The phenomenon of fuel growth introduces a monotonically increasing strain which accompanies the cyclic strain. The effects of such a gradually accumulating increment of strain were investigated and were found to be adequately covered by the adjustment for maximum mean stress. Design curves were constructed from the mean failure curves by applying approximate factors to cover the effects of size, environment, surface finish, and scatter of data. The results of fatigue tests on notched irradiated Zircaloy indicate that this material is somewhat less notch sensitive than 100,000 psi tensile strength steel. Non-irradiated Zircaloy is even less notch sensitive. However, fatigue tests on notched weld metal indicate considerably greater notch sensitivity.

10. "Fatigue Properties of Irradiated Pressure Vessel Steels," by W. G. Gibbons, A. E. Mikoleit, and W. J. O'Donnell, ASTM publication STP-426, Effects of Irradiation on Structural Metals, November 1967.
The effects of neutron irradiation on the unnotched strain-cycled fatigue properties of pressure vessel steels were evaluated. Two heats of A302B low alloy steel and one heat of A212B carbon silicon steel were investigated. Results from room temperature tests on non-irradiated material were compared with those from irradiated material. The fatigue notch sensitivities of these materials were also investigated using V-notch specimens with two and ten mil root radii. Results were compared with theoretical predictions based on the stress theory of fatigue notch sensitivity.

11. "Upper Bounds for Accumulated Strains Due to Creep Ratcheting," by W. J. O'Donnell and J. S. Porowski, Transactions ASME, Journal of Pressure Vessel Technology, Vol. 97, No. 3, August 1975.
A rigorous method of bounding both the total accumulated strain and the strain ranges due to cyclic operation in the creep regime is presented. These limits can be obtained from the results of purely elastic stresses analyses. The basic problem of a cylindrical vessel under internal pressure subjected to cyclic thermal stresses is solved in detail. The results are presented in graphical form suitable for design purposes.

12. "Fatigue Design Criteria for Pressure Vessel Alloys," by C. E. Jaske and W. J. O'Donnell, Transactions ASME, Journal of Pressure Vessel Technology, Vol. 99, No, 4, November 1977.
Fatigue design criteria for pressure vessel steels are developed herein based on analysis of available material data between room temperature and 487C (800 F). Strain controlled low-cycle and high-cycle fatigue data for austenitic steels, Alloy 800, Alloy 600, and Alloy 718 were evaluated. The effect of mean stresses were considered and design curves were proposed for use in Sections III and VIII of the ASME Boiler and Pressure Vessel Code.

13. "Theory of Free Coiled Pressure Vessels," by J. S. Porowski, W. J. O'Donnell, and A.S. Roberts, presented at the ASME/CSME Pressure Vessels and Piping Conference, Montreal, Canada, June 1978. 39. "Plastic Design of Ligaments," by W. J. O'Donnell and J. S. Porowski, ASME Pressure VesselsPiping Conference, San Francisco, California, ASME 79:PVP Vol. 37, June 1979.

14. "Creep Tensile Instability," by W. J. O'Donnell and J. S. Porowski, presented at the Fourth International Conference on Pressure Vessel Technology, London, England, Proceedings, May 1980.
Creep tensile instability solutions are obtained herein for most cases encountered in design applications. These include: (1) membrane load stresses of arbitrary biaxiality (2) pressurized spherical vessels, and (3) pressurized cylindrical vessels and piping with combined axial loads. Solutions are obtained for both the effective (Mises) strains and the maximum tensile strains at instability. The results show that neither Triaxiality Factors nor factors based on plastic tensile instability solutions can be used to convert creep rupture ductility to safe allowable design values for components operating in the creep regime. The present solutions can be used to obtain allowable strains for design applications using available uniaxial creep rupture ductility data.

15. "More Efficient Creep Ratcheting Bounds," by J. S. Porowski and W. J. O'Donnell, ORNL Report 7322/1, October 1978.
The O'Donnell-Porowski upper bound solutions for creep ratcheting are extended to include material hardening effects and temperature- dependent yield properties. Energy methods are introduced in order to obtain more efficient bounds for loading histograms involving a limited number of severe cycles in the plastic ratcheting regime, interspersed with cycling of lesser magnitude.

16. "Development of Inelastic Design Criteria and Codes," by W. J. O'Donnell and J. S. Porowski, invited lecture, Fifth International Conference on Structural Mechanics in Reactor Technology, Berlin, Germany, SMIRT Transactions, Vol. L 6/1, August 1979.

17. "Creep Ratcheting Bounds for Cycling Primary and Seismic Loading," by J. S. Porowski and W. J. O'Donnell, presented at ASME Pressure Vessels and Piping Conference, San Francisco, California, June 1979.

18. "Simplified Inelastic Methods for Bounding of Fatigue and Creep Rupture Damage," by W. J. O'Donnell, J. S. Porowski, and M. L. Badlani, presented at ASME Century II Conference, San Francisco, California, August 1980. Transactions ASME, Journal of Pressure Vessel Technology, Vol. 102, p. 394, November 1980.
Bounds on inelastic strain ranges and maximum residual stresses introduced by transient operating conditions are obtained. These strain ranges and maximum residual stresses can be used to determine fatigue damage and creep rupture damage. Methods for integrating creep rupture damage during relaxation of surface stresses are also included. The solutions are based on uniaxial models.

19. "A Simplified Design Procedure for Life Prediction of Rocket Thrust Chambers," by J. S. Porowski, W. J. O'Donnell, M. L. Badlani, B. Kasraie, and H. J. Kasper, presented at AIAA/ASME/SAE Joint Propulsion Conference, Cleveland, Ohio, AIAA Paper 82-1251, June 21-23, 1982.
An analytical procedure for predicting thrust chamber life is developed. The hot-gas-wall ligaments separating the coolant and combustion gas are subjected to pressure loading and severe thermal cycling. The resulting stresses interact during plastic straining causing incremental bulging of the ligaments during each firing cycle. This mechanism of plastic ratcheting is analyzed and a method using a yield surface for combined bending and membrane loading developed for determining the incremental permanent deflection and progressive thinning near the center of the ligaments. Fatigue and tensile instability are analyzed as possible failure modes. Results of the simplified analyses compare favorably with available experimental data and finite element analysis results for OFHC (Oxygen Free High Conductivity) copper. They are also in reasonably good agreement with experimental data for Naraloy Z, a copper-zirconium-silver alloy developed by the Rocketdyne Division of Rockwell International.

20. "Vessels for Elevated Temperature Service," by W. J. O'Donnell and J. S. Porowski, Chapter One, Developments in Pressure Vessel Technolgy:4, Book published by Applied Science Publishers Ltd., England, Edited by R. W. Nichols, 1983.

21. "Development of a Simplified Procedure for Rocket Engine Thrust Chamber Life Prediction with Creep," by M. L. Badlani, B. Kasraie, J. S. Porowski, W. J. O'Donnell, and D. B. Peterson, NASA Report CR-165585, October, 1981.

22. "Potential Development of Improved Fatigue Design Methods," by G. H. Weidenhamer and W. J. O'Donnell, presented at ASME Winter Annual Meeting, New Orleans, Louisiana, December 10-14, 1984, ASME Paper 84-WA/PVP-6.

23. "Fatigue and Creep Rupture Damage of Perforated Plates Subjected to Cyclic Plastic Straining in Creep Regime," by M. L. Badlani, T. Tanaka, J. S. Porowski, and W. J. O'Donnell, Welding Research Council Bulletin No, 307, August 1985.

24. "On Design of Discontinuities in Structures for Elevated Temperature Service," by G. Baylac, B. Kasraie, J. S. Porowski, W. J. O'Donnell, and M. L. Badlani, Eighth International Conference on Structural Mechanics in Reactor Technology, SMIRT Transactions, Vol. L, August 19:23, 1985.

25. "Low Cycle Thermal Fatigue and Fracture of Reinforced Piping," by W. J. O'Donnell, J. M. Watson, W. B. Mallin, and J. R. Kenrick. International Conference and Exposition on Fatigue, Corrosion Cracking, Fracture Mechanics and Failure Analysis, December 2 - 6, 1985, Salt Lake City, Utah, Proceedings published by ASM "Analyzing Failures: The Problems and the Solutions," (ASM 8517-007).
A large diameter steel pipe reinforced by stiffening rings with saddle supports was subjected to thermal cycling as the system was started up, operated and shut down. The pipe sustained local buckling and cracking, then fractured during the first five month operation. Failure was due to low cycle fatigue and fast fracture caused by differential thermal expansion stresses. Thermal lag between the stiffening rings welded to the outside welded to the outside of the pipe and the pipe wall itself resulted in large radial and axial thermal stresses at the welds. Redundant tied down saddle supports in each segment of pipe between expansion joints restrained pipe arching due to circumferential temperature variations, producing large axial thermal bending stresses. Thermal cycling of of the system initiated fatigue cracks at the stiffener rings. When the critical crack size was reached, fast fracture ocurred. The system was redesigned by eliminating the redundant restraints which prevented axial bowing, and by modifying the stiffener rings to permit free radial thermal breathing of the pipe. Expert testimony was also provided in litigation resulting in a court decision requiring the designers of the original system to pay damages to the furnace owner.

26. "Improved Fatigue Life Evaluation Methods for LWR Components," by W. J. O'Donnell, D. P. Jones, J. S. Abel, J. S. Porowski, E. J. Hampton, and M. L. Badlani, report prepared for Division of Engineering Technology, Office of Nuclear Regulatory Research, March 1987.

27. "Mechanical Methods of Improving Resistance to Stress Corrosion Cracking in BWR Piping Systems," J. Abel, J. Titrington, R. Jordan, J. S. Porowski, W. J. O'Donnell, M. L. Badlani, and E. Hampton, SMIRT Post Conference, Lausanne, Switzerland, August, 1987.

28. "Synthesis of S-N and da/dn Life Evaluation Technologies," by W. J. O'Donnell, presented at the American Society of Mechanical Engineers, Pressure Vessels and Piping Conference, Pittsburgh, Pa., PVP Vol. 10, 1988.
The S-N technology used in the ASME Code and similar design criteria includes both the crack initiation and crack propagation phases of fatigue failure. Crack growth rate technology has successfully quantified various environmental (corrosion) cyclic rate, and (to a lesser extent) on the threshold crack growth values. The relationship between safe life evaluations based on these technologies is analyzed herein, and a general method of quantifying known crack growth rate effects in S-N curves is developed. Fatigue tests on polished specimens are characterized by the nomimal stress amplitudes over yield, where linear elastic fracture mechanics methods, such as those used in the ASME Code, are not valid. The small plastic zone corrections used in the Code do not account for the plastic driving energies encountered in low-cycle fatigue testing. J-integral solutions, equivalent to COD solutions are adapted herein to evaluate the growth of cracks in these specimens. This approach is shown to correlate the growth of cracks over the entire range of loading from elastic to grossly plastic conditions, in specimens of widely different geometries and sizes, including the growth of very short cracks for materials of major interest in pressure vessels and piping. The analytical approach developed herein can be used to correct S-N fatigue life evaluation curves for known differences in crack growth rates whether they are due to corrosion-assisted fatigue or other variables. As an illustration, the crack growth rates given in Section XI of the ASME Code are used to include reactor water environmental effects on A533 reactor pressure vessel steel in the fatigue design curves of Section III.

29. "Advanced Methods of Improving Resistance to Stress Corrosion Cracking in BWR Piping Systems," by J. S. Abel, J. Titrington, R. Jordan, J. S. Porowski, W. J. O'Donnell, M. L. Badlani, and E. J. Hampton, presented at the American Society of Mechanical Engineers Pressure Vessels and Piping Conference, June 19 - 23, 1988, PVP Vol. 13, 1988.
Pipelocks and the Mechanical Stess Improvement Process (MSIP) have been applied in BWR plants. Pipelocks restore the integrity of the weldments with identified cracks. MSIP removes the residual tensile stresses from weldments, thus preventing initiation of cracks or retarding growth of pre-existing flaws in piping systems. MSIP was applied for various geometries of weldments including nozzle-to-safe-end joints. Extensive verification has been completed by the United States Nuclear Regulatory Commission, EPRI and Argonne National Laboratory. Basic concepts and practical application of MSIP and Pipelocks are presented.

30. "Aging and Reactor Water Effects on Fatigue Life," by W. J. O'Donnell, J. S. Porowski, E. J. Hampton, M. L. Badlani, G. H. Weidenhamer, D. P. Jones, J. S. Abel, and B. Tomkins, presented at International Nuclear Power Plant Aging Symposium, Washington, D. C., August 30, 1988, Proceedings published by USNRC March 1989, NUREG/CP-0100.
Methods of including aging effects and reactor water enhanced crack propagation rates in Codified S-N fatigue life assessment curves are presented and illustrated. Such methods are essential because it is not feasible to produce experimentally based S-N life evaluation curves for all of the relevant cyclic rate and environmental conditions of interest within available finite research funding. Reactor water environmental effects are known to accelerate fatigue crack growth rates in reactor pressure vessel and piping materials. Recently developed advanced elastic-plastic fracture mechanics technology (Ref. 1) is used herein as a means of correcting S-N fatigue life evaluation curves for measuring enviromental cracck growth rates effects. As an important illustration, ASME Code Section XI reactor water crack growth rate curves are used to generate revised new Section III and VIII fatigue design curves for A106 reactor piping. Reactor water effects on the fatigue life are found to be quite significant, and their inclusion in the S-N curves greatly improves the technical basis for assessing the residual component life which meets ASME Code safety margins for cumulative fatigue.

31. "Proposed New ASME Code Rules for Elastic Creep-Fatigue Evaluations," by W. J. O'Donnell, IMechE Seminar on Recent Advances in Design Procedures for High Temperature Plant, United Kingdom, November 1988.

32. "Reactor Water Effects on Fatigue Life," by W. J. O'Donnell, J. S. Porowski, E. J. Hampton, M. L. Badlani, G. H. Weidenhamer, D. P. Jones, J. S. Abel and B. Tomkins. Fatigue Initiation, Propagation, and Analysis for Code Construction, MPC-Vol. 29, ASME Winter Annual Meeting, Chicago, Illinois, November 27 - December 2, 1988.
Elastic-plastic methods of including known environmentally-assisted fatigue crack growth rate effects in the S-N fatigue life evaluation curves were recently developed (Ref. (1)). These methods are based on J-integral solutions for cracks in strain-controlled unnotched low-cycle fatigue specimens. They are used herein to include Section XI reactor water crack growth rates in the ASME Code fatigue design curves for A106 piping material. Reactor water effects on the fatigue life are found to be quite significant.

33. "A New Role for Engineers in a Competitive World Economy," by W. J. O'Donnell, Plenary Lecture, presented at the 1988 ASME Pressure Vessels and Piping Conference, Pittsburgh, Pa., June 1988.

34. "Development of Fatigue Criteria for Remaining Life Assessment of Shell Structures," by J. S. Porowski, W. J. O'Donnell, M. L. Badlani, S. Chattopadhyay, and S. S. Palusamy, MPC-Vol. 29, pp. 115-123, December 1988.

35. "Bounds on Creep Ratcheting in ASME Code," J. S. Porowski, M. L. Badlani, and W. J. O'Donnell, 1989 PVP Conference, Honolulu, Hawaii, July 23-27, 1989.
For more than a decade, simplified methods for bounding creep ratcheting strains have been used in the ASME Code to design components for elevated temperature service. The background and a brief history of the development of the rules is given. Current simplified methods in Code Case N-47 are applicable for complex cycling load histories including severe cycles which may result in plastic strain increments.

36. "ASME Code Program to Develop Improved Fatigue Design Criteria," by W. J. O'Donnell, J.S. Porowski, M. L. Badlani, E. J. Hampton (SMC O'Donnell),G.H. Weidenhamer (U.S. Nuclear Regulatory Commission). Post-SMIRT Conference, Seminar No. 15, Construction Codes & Engineering Mechanics, Anaheim, California, August 22, 1989.

37. "Use of Mechanical Stress Improvement Process to Mitigate Stress Corrosion Cracking in BWR Piping Systems," by J. S. Porowski, W. J. O'Donnell, M. L. Badlani, and E. J. Hampton. Nuclear Engineering and Design 124, pp. 91-100, Elsevier Science Publishers, February 1990.
The Mechanical Stress Improvement Process (MSIP) has been extensively applied to prevent stress corrosion cracking in BWR plants. MSIP removes residual tensile stresses from weldments, thus preventing the initiation of cracks and retarding the growth of pre-existing flaws in piping systems. The process involves a slight permanent contraction of the pipe on one side of the weldment. The resulting plastic flow redistributes the residual as-welded stresses and generates beneficial compressive stresses at the inner pipe surface in the region of the weldment including the weld metal and heat affected zones. MSIP imposes only monotonic compressive plastic strains and does not require severe temperature gradients. Hence, use of MSIP is particularly advisable for weldments which have geometrical or material discontinuities such as nozzle-to-safe-end welds. Moreover, the process can be applied to the piping system either filled with water or empty. MSIP is accepted by NUREG 0313 as a Stress Improvement (SI) process for mitigation of IGSCC in BWR plants. To date, it has been applied to 532 welds in 12 BWR plants in the United States and abroad. MSIP has been used to improve 157 nozzle weldments ranging from 4" to 28" diameter. The process has also been applied to weldments with pre-existing cracks. The basic concept, results of analyses and tests, and application of MSIP are described herein.

38. "Emerging Technology for Component Life Assessment," by W. J. O'Donnell and J. S. Porowski, presented at ASME Pressure Vessel and Piping Conference, San Diego, California, June 24, 1991. International Journal Pressure Vessel & Piping, No. 50 (1992) pp. 37-61.

39. "Use of Mechanical Stress Improvement for Weldments with Cracks," by J. S. Porowski, W. J. O'Donnell, M. L. Badlani, and E. J. Hampton, Proceedings, SMIRT Post Conference Seminar No. 2, "Assuring Structural Integrity of Steel Reactor Pressure Boundary Components," Taipei, R. O. C., August 26-28, 1991.

40. "New Mechanical and Thermal Processes for Mitigating Stress-Corrosion and Corrosion-Accelerated Fatigue," by J. S. Porowski, W. J. O'Donnell, M. L. Badlani, E. J. Hampton, and B. Kasraie, presented at ASME Pressure Vessel and Piping Conference, San Diego, California, June 24, 1991, International Journal Pressure Vessel & Piping, No. 50 (1992) pp. 63-79.

41. "Methods for Evaluating the Cyclic Life of Nuclear Components Including Reactor Water Environmental Effects," by W. J. O'Donnell, J. S. Porowski, N. Irvine, B. Tomkins, D. Jones, and T. O'Donnell, Presented at ASME Pressure Vessel and Piping Conference, New Orleans, Louisiana, June 21-21, 1992, PVP Vol. 238, ASME 1992.

42. "Primary Stress Evaluations for Redundant Structures," by W. J. O'Donnell, J. S. Porowski, B. Kasraie, G. Bielawski, and M. L. Badlani, presented at the ASME Pressure Vessel and Piping Conference, Denver, Colorado, July 25-29, 1993, ASME PVP Vol. 265, Design Analysis, Robust Methods and Stress Classification.

43. "Crack Growth and Fatigue in Reactor Water," by W. J. O'Donnell, presented at ASME Pressure Vessel & Piping Conference, Honolulu, Hawaii, July 23-27, 1995, International Journal of Pressure Vessels & Piping Codes & Standards, PVP-Vol. 313-1, p. 189.

44. "Operating Nuclear Plant Feedback to ASME and French Codes," by J. Journet and William J. O'Donnell, presented at the ASME Pressure Vessel and Piping Conference, Montreal, Canada, July 21-28, 1996, Pressure Vessel and Piping Codes and Standards, PVP Vol. 339-2, pp. 3-12.

45. "Weight-Saving Plastic Design of Pressure Vessels," by J.S. Porowski, William J. O'Donnell and R.H. Reid, ASME Transactions, Journal of Pressure Vessel Technology, Vol. 119, Feb. 1997.
Within the last two decades, the use of elastic finite element analyses to demonstrate design compliance with the rules of the ASME Code has become a generally accepted engineering practice. Linearized stresses from these analyses are commonly used to evaluate Primary stresses. For redundant structures or complex structural details, the use of such analyses, instead of simple equlibrium models, often results in significant overconservatism. Direct use of finite elemnt analyses is often preferred because solutions are not unique, and effective equlibrium models are not easily constructed for complex three-dimensional structures. However, finite element analyses include Secondary stresses even for pressure, mechanical and shock loading. The use of finite element inelastic analysis to partition mechanically induced stresses into the Primary and Secondary categories was introduced in Ref. (1). The authors have since used this approach to design more efficient structures. The practical application of this method to reduce the weight of complex redundant structures designed to meet Primary stress limits is described herein. Plastic design utilizes the ability of actual materials to find the most efficient load distribution. A heat exchanger subjected to pressure, accelerations, and nozzle external loads is evaluated as a practical example. The results of elastic analyses are compared with those obtained by inelastic analyses. It is shown that inelastic analyses can be used to reduce the weight of structures using only PC's for the engineering computations.

45. "Proposed New Fatigue Design Curves for Carbon and Low Alloy Steels in High Temperature Water," by William J. O'Donnell, William John O'Donnell and Thomas P. O'Donnell, Proceedings of ASME PVP Conference, Technologies for Safe & Efficient Energy Conversion, July 17-21, 2005, Denver, CO.