DOI QR코드

DOI QR Code

Experimental and numerical analysis of fatigue behaviour for tubular K-joints

  • Received : 2004.04.05
  • Accepted : 2004.12.29
  • Published : 2005.04.20

Abstract

In this paper, a full-scale K-joint specimen was tested to failure under cyclic combined axial and in-plane bending loads. In the fatigue test, the crack developments were monitored step by step using the alternating current potential drop (ACPD) technique. Using Paris' law, stress intensity factor, which is a fracture parameter to be frequently used by many designers to predict the integrity and residual life of tubular joints, can be obtained from experimental test results of the crack growth rate. Furthermore, a scheme of automatic mesh generation for a cracked K-joint is introduced, and numerical analysis of stress intensity factor for the K-joint specimen has then been carried out. In the finite element analysis, J-integral method is used to estimate the stress intensity factors along the crack front. The numerical stress intensity factor results have been validated through comparing them with the experimental results. The comparison shows that the proposed numerical model can produce reasonably accurate stress intensity factor values. The effects of different crack shapes on the stress intensity factors have also been investigated, and it has been found that semi-ellipse is suitable and accurate to be adopted in numerical analysis for the stress intensity factor. Therefore, the proposed model in this paper is reliable to be used for estimating the stress intensity factor values of cracked tubular K-joints for design purposes.

Keywords

References

  1. American Petroleum Institute (1993), Recommended Practice for Planning, Designing and Constructing Fixed Offshore Platforms. American Petroleum Institute, Washington, DC, API
  2. American Welding Society (1996), ANSI/AWS D1.1-96 Structural Welding Code-Steel. Miami, USA
  3. Bowness, D. and Lee, M.M.K. (1995), 'The development of an accurate model for the fatigue assessment of doubly curved cracks in tubular joints', Int. J. Fracture, 73, 129-147 https://doi.org/10.1007/BF00055725
  4. Bowness, D. and Lee, M.M.K. (1996), 'Stress intensity factor solutions for semi-elliptical weld-toe cracks in T-butt geometries', Fatigue Fract. Engng Mater. Struct., 19(6), 787-797 https://doi.org/10.1111/j.1460-2695.1996.tb01323.x
  5. Cao, J.J., Yang, G.J. and Packer, J.A. (1997), 'FE mesh generation for circular tubular joints with or without cracks', Proc. 7th Int. Offshore and Polar Eng. Conf., Honolulu, 6, 98-105
  6. Chong Rhee, H., Han, S. and Gipson, G.S. (1991), 'Reliability of solution method and empirical formulas of stress intensity factors for weld toe cracks of tubular joints', Proc. 10th Offshore Mechanics and Arctic Eng. Conf., ASME, 3(B), 441-452
  7. Department of Energy (DEn), (1993), 'Background to new fatigue design guidance for steel joints in offshore structures', Internal Report, London, UK
  8. Huang, Z.W. (2002), 'Stress intensity factor of cracked steel tubular T and Y-joints under complex loads', PhD Thesis, Nanyang Technological University, Singapore
  9. Shih, C.F. and Asaro, R.J. (1988), 'Elastic-plastic analysis of cracks on bimaterial interfaces: Part I - Small scale yielding', J. Appl. Mech., 299-316
  10. Technical Software Consultant Ltd. (TSC) (1991), ACFM Crack Microgauge - Model U10, Milton Keynes, UK
  11. Zhao, X.L., Herion, S., Packer, J.A., Puthli, R., Sedlacek, G., Wardenier, J., Weynand, K., van Wingerde, A. and Yeomans, N. (2001), Design Guide for Circular and Rectangular Hollow Section Joints under Fatigue Loading. CIDECT, TUV

Cited by

  1. Stress-intensity factors for circular hollow section V-joints with a rack-plate chord vol.32, pp.1, 2009, https://doi.org/10.1111/j.1460-2695.2008.01321.x
  2. Hysteretic performance of circular hollow section tubular joints with collar-plate reinforcement vol.67, pp.12, 2011, https://doi.org/10.1016/j.jcsr.2011.06.010
  3. Hysteretic behaviour of SHS brace-H-shaped chord T-joints with transverse stiffeners vol.122, 2018, https://doi.org/10.1016/j.tws.2017.10.023
  4. Fatigue and residual strength of concrete-filled tubular X-joints with full capacity welds vol.100, 2014, https://doi.org/10.1016/j.jcsr.2014.04.021
  5. The Influence of Crack Propagation Angle on the Stress Intensity Factors (SIFs) of Cracked Tubular T-Joints vol.18, pp.2, 2018, https://doi.org/10.1007/s13296-018-0006-1
  6. Static test on failure process of tubular T-joints with initial fatigue crack vol.24, pp.5, 2005, https://doi.org/10.12989/scs.2017.24.5.615
  7. Fatigue behaviour of non-integral Y-joint of concrete-filled rectangular hollow section continuous chord stiffened with perfobond ribs vol.191, pp.None, 2019, https://doi.org/10.1016/j.engstruct.2019.04.089