Shakedown analysis of 90-degree mitred pipe bends. (English) Zbl 1406.74574
Summary: The behaviours of smooth 90-degree pipe bends under cyclic loading have received substantial attention in recent years where shakedown and ratchetting domains have been determined. However, such data are considerably lacking for mitred pipe bends. In the current research, the lower bound shakedown limit loads of 90-degree mitred pipe bends are determined via a simplified direct non-cyclic numerical technique recently developed by H. F. Abdalla et al. [“A simplified technique for shakedown limit load determination”, Nuclear Eng. Des. 237, No. 12–13, 1231–1240 (2007; doi:10.1016/j.nucengdes.2006.09.033)]. The analysed mitred pipe bends are subjected to the combined effect of steady internal pressures and cyclic in-plane or out-of-plane bending moments. Both in-plane closing and opening bending moment cases are considered. The shakedown boundaries of three mitred pipe bend geometries with one, two, and three welded joints are determined and compared with the shakedown boundary of a smooth 90-degree pipe bend. All analysed bends have diameter to thickness ratio of 25 and bend radius of 1.5 times the pipe mean diameter. The results indicate that the shakedown boundaries of mitred bends have reduced domains compared with the smooth pipe bend of similar geometrical parameters. Shakedown domains of mitred bends increase in size as the number of welded joints increase until it approaches the shakedown boundary of the smooth pipe bend simulating a mitred bend with infinite number of welded joints. The percentage of the area under shakedown domain for the mitred pipe bends to that of the smooth pipe bend ranges from 20% for the single mitred pipe bend to 75% for the 3-weld mitred bend. Results also revealed that reducing the number of mitred welded joints, dominates reversed plasticity response at the expense of ratchetting response. Out-of-plane bending generally showed larger shakedown domain than the in-plane bending shakedown domain. Additionally, the shakedown domains for in-plane closing and opening moments are quite similar.
MSC:
| 74R05 | Brittle damage |
| 74C05 | Small-strain, rate-independent theories of plasticity (including rigid-plastic and elasto-plastic materials) |
Keywords:
mitred pipe bend; shakedown; ratchetting; reversed plasticity; limit load; smooth pipe bendReferences:
| [1] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., Determination of shakedown limit load for 90-degree pipe bend using a simplified technique, ASME Journal of Pressure Vessel and Technology, 128, 618-624, (2006) |
| [2] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., A simplified technique for shakedown limit load determination, Nuclear Engineering and Design, 237, 1231-1240, (2007), Winner of Jaeger Prize SMiRT-18 |
| [3] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., Comparison of pipe bend ratchetting/shakedown test results with the shakedown boundary obtained via a simplified technique, (2009), Proceedings of the ASME - PVP Division Conference, Prague, Czech Republic |
| [4] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., A simplified technique for shakedown limit load determination of a larg square plate with a small central Hall under cyclic biaxial loading, Nuclear Engineering and Design, 3, 657-665, (2011) |
| [5] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., Shakedown limit loads for 90 degree scheduled pipe bends subjected to steady internal pressure and cyclic bending moments, Journal of Pressure Vessel Technology, 133, 031207.1-031207.12, (2011) |
| [6] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., Determination of shakedown limit loads for a cylindrical vessel-nozzle intersection via a simplified technique, ASME - PVP Division Conference, 3, 833-844, (2011) |
| [7] | Abdalla, H. F.; Megahed, M. M.; Younan, M. Y., Shakedown analysis of a cylindrical vessel-nozzle intersection subjected to steady internal pressures and cyclic out-of-plane bending moments, (2012), ASME Transactions, PVP Division Conference, Toronto, Ontario, Canada |
| [8] | Bree, J., Elastic-plastic behaviour of thin tubes subjected to internal pressure and intermittent high heat fluxes with application to fast nuclear reactor fuel elements, Journal of Strain Analysis, 2, 226-238, (1967) |
| [9] | Carter, P., Analysis of cyclic creep and rupture. part 2: calculation of cyclic reference stresses and ratcheting interaction diagrams, International Journal of Pressure Vessels and Piping, 82, 1, 27-33, (2005) |
| [10] | Carter, P., Analysis of cyclic creep and rupture. part 1: bounding theorems and cyclic reference stresses, International Journal of Pressure Vessels and Piping, 82, 1, 15-26, (2005) |
| [11] | Chang-Sik, Oh.; Yun-Jae, K.; Chi-Yong, P., Shakedown limit loads for elbows under internal pressure and cyclic in-plane bending, International Journal of Pressure Vessels and Piping, 85, 6, 394-405, (2008) |
| [12] | Chen, H. F.; Ponter, A. R., Shakedown and limit analyses for 3-D structures using the linear matching method, International Journal of Pressure Vessels and Piping, 78, 6, 443-451, (2001) |
| [13] | Code, ASME Boiler and Pressure Vessel. Nuclear Power Plant Components, (2007), ASME New York, USA |
| [14] | Dhalla, A. K., Simplified procedure to classify stresses for elevated temperature service, Transactions of the ASME - PVP Division, 120, 177-178, (1987) |
| [15] | El-Saadany, M. S.; Younan, M. Y.A.; Abdalla, H. F., Determination of shakedown boundary and fitness-assessment diagrams for cracked pipe bends, (July 2012), ASME Transactions, PVP Division Conference, Toronto, Ontario, Canada |
| [16] | Hafiz, Y. A.; Younan, M. Y.A.; Abdalla, H. F., Limit & shakedown loads determination for locally thinned wall pipe branch connection subjected to pressure and bending moments, (July 2012), ASME Transactions, PVP Division Conference, Toronto, Ontario, Canada |
| [17] | Leckie, F. A.; Penny, R. K., Shakedown pressure for radial nozzles in spherical pressure vessels, International Journal of Solids and Structures, 3, 743-755, (1967) |
| [18] | Mackenzie, D.; Boyle, J., Simple method of estimating shakedown loads for complex structures, Transactions of the ASME - PVP Division, 265, 89-94, (1993) |
| [19] | Marriott, D. L., Evaluation of deformation or load control of stresses under inelastic conditions using elastic finite element stress analysis, Transactions of the ASME - PVP Division, 136, 3-9, (1988) |
| [20] | Melan, E., Theorie statisch unbestimmter systeme aus ideal Plastischean baustoff, Sitzber. Akad. Wiss. Wien IIa, 145, 195-218, (1936) · JFM 62.1547.01 |
| [21] | Parkes, E. W., Structural effects of repeated thermal loading, (Benham; etal., Thermal Stress, (1964), Pitman London) |
| [22] | Seshadri, R., Generalized local stress strain (gloss) analysis. theory and applications, ASME Journal of Pressure Vessel Technology, 113, 2, 219-227, (1991) |
| [23] | Vermaak, N.; Valdevit, L.; Anthony, E.; Frank, Z.; Robert, M., Implementations of shakedown for design of actively cooled thermostructural panels, Mechanics of Materials and Structures, 6, 9-10, (2011) |
| [24] | Vlaicu, D., Shakedown analysis of axisymmetric nozzles under primary and secondary cyclic loads, (2009), ASME Transactions, PVP Division Conference, Prague, July 2009 |
| [25] | Von Kàrmàn, Th, Über die formänderung Dünnwandiger Röhre, insbesondere federnder ausgleichröhre, Zeitshrift des Vereines Deutscher Ingenieure, 55, 1889-1895, (1911) |
| [26] | Wood, J., Stresses in the vicinity of an un-reinforced mitre intersection: an experimental and finite element comparison, Journal of Strain Analysis for Engineering Design, 42, 5, 325-336, (2007) |
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