Abstract
Studying the reliability of cracked structures under different types of failure modes such as a mixture of Mode I and Mode II loadings has been of great importance in many applications. The purpose of this study is to evaluate the effects of different modes of loading, i.e. pure Mode I, pure Mode II and Mixed mode I/II loadings on the reliability of cracked structures via three typical case studies including 1st: through crack in a very wide plate, 2nd: cracked pressurized fuselage and 3rd: cracked fastener holes under actual geometries and loading conditions using the FORM, the fracture toughness and the equivalent SIF for Mixed mode I/II loading which is extracted by the Energy release rate model 1. The MCS was used to check the accuracy of the FORM. It was found that the failure probability decreases significantly as the loading mode changes from the pure Mode I to pure Mode II. This means that the reliability in the Mixed mode I/II loading is higher than that of pure Mode I and smaller than for pure Mode II. Also, it was concluded that the failure probability decreases with increasing of the angle of crack for the Mixed mode I/II loading conditions. The results indicated that the angle of crack and the applied stress are the two variables which have the most significant influence on the reliability.
Similar content being viewed by others
Abbreviations
- K I , K II :
-
stress intensity factor (SIF) in Mode I and Mode II
- K (I,II) :
-
equivalent SIF in Mixed mode I/II loading
- K IC , K IIC :
-
fracture toughness in Mode 1 and Mode II
- K (I,II)C :
-
fracture toughness in Mixed mode I/II loading
- PF :
-
failure probability
- SI Xi :
-
the sensitivity index of variable X i
- β :
-
safety index or reliability index
- σ Z :
-
standard deviation of variable Z
- μ Z :
-
mean value of variable Z
- S :
-
load normal variable
- R :
-
resistance normal variable
- Z :
-
new variable of limit state function
- Φ:
-
cumulative distribution function for a standard normal variable
- σ :
-
applied stress
- a :
-
crack size
- α :
-
dimensionless geometry correction factor
- Beta :
-
angle between the normal plane to the crack and stress axis
- C.O.V :
-
coefficient of variance
References
Verma, A. K., Srividya, A., and Karanki, D. R., “Structural Reliability,” in: Reliability and Safety Engineering, Verma, A. K., Srividya, A., Karanki, D. R., (Eds.), Springer, pp. 257–292, 2010.
Stephens, R. I., Fatemi, A., Stephens, R. R., and Fuchs, H. O., “Metal Fatigue in Engineering,” John Wiley & Sons, 2nd Ed., pp. 19–92, 122-185, 2000.
Anderson, T. L., “Fracture Mechanics: Fundamentals and Applications,” CRC Press, 3rd Ed., 2005.
John, B. and Stanley, T. R., “Fracture and Fatigue Control in Structures,” Applications of Fracture Mechanics, Butterworth-Heinemann, 3rd Ed., 1999.
Lee, O. S., Kim, D. H., and Choi, S. S., “Reliability of Buried Pipeline using a Theory of Probability of Failure,” Solid State Phenomena, Vol. 110, pp. 221–230, 2006.
Lee, O. S. and Kim, D. H., “The Reliability Estimation of Pipeline using FORM, SORM and Monte Carlo Simulation with FAD,” Journal of Mechanical Science and Technology, Vol. 20, No. 12, pp. 2124–2135, 2006.
Lee, O. S., Kim, D. H., and Park, Y. C., “Reliability of Structures by using Probability and Fatigue Theories,” Journal of Mechanical Science and Technology, Vol. 22, No. 4, pp. 672–682, 2008.
Lee, O. S. and Kim, D. H., “Effects of Crack Geometries on Reliabilities using Probability Theories,” Int. J. Precis. Eng. Manuf., Vol. 10, No. 3, pp. 119–126, 2009.
Peters, R. W. and Kuhn, P., “Bursting Strength of Unstiffened Pressure Cylinders with Slits,” National Advisory Committee for Aeronautics, 1957.
Venkatesha, B. K., Prashanth, K. P., and Deepak Kumar, T., “Investigation of Fatigue Crack Growth Rate in Fuselage of Large Transport Aircraft using FEA Approach,” Global Journal of Research and Engineering-GJRE-A, Vol. 14, No. 1, pp. 13–22, 2014.
Chow, W. T. and Atluri, S. N., “Fracture and Fatigue Analysis of Curved or Kinked Cracks Near Fastener Holes,” Finite Elements in Analysis and Design, Vol. 23, No. 2, pp. 91–100, 1996.
Sasaki, T. and Honda, T., “An Experimental Study on Fatigue Crack Growth in Lap Joints with Multiple Fastener Holes,” WIT Transactions on Engineering Sciences, Vol. 37, DOI No. 10.2495/ DM020221, 2002.
Mahadevan, S. and Haldar, A., “Reliability Assessment using Stochastic Finite Element Analysis,” John Wiley & Sons, 2000.
Mahadevan, S. and Haldar, A., “Probability, Reliability, and Statistical Methods in Engineering Design,” John Wiley & Sons, 2000.
Tanaka, K., “Fatigue Crack Propagation from a Crack Inclined to the Cyclic Tensile Axis,” Engineering Fracture Mechanics, Vol. 6, No. 3, pp. 493–507, 1974.
Xiangqiao, Y., Zeha, Z., and Shanyi, D., “Mixed-Mode Fracture Criteria for the Materials with Different Yield Strengths in Tension and Compression,” Engineering Fracture Mechanics, Vol. 42, No. 1, pp. 109–116, 1992.
Sih, G. C., Nisitani, H., Kyushu, S. D., and Ishihara, T., “Role of Fracture in Modern Technology: Proceedings of the International Conference,” Elsevier Science Ltd., 1987.
Rhee, H. C. and Salama, M. M., “Mixed-Mode Stress Intensity Factor Solutions of a Warped Surface Flaw by Three-Dimensional Finite Element Analysis,” Engineering Fracture Mechanics, Vol. 28, No. 2, pp. 203–209, 1987.
Forth, S. C., Favrow, L. H., Keat, W. D., and Newman, J. A., “Three-Dimensional Mixed-Mode Fatigue Crack Growth in a Functionally Graded Titanium Alloy,” Engineering Fracture Mechanics, Vol. 70, No. 15, pp. 2175–2185, 2003.
Liu, Y. and Mahadevan, S., “Threshold Stress Intensity Factor and Crack Growth Rate Prediction under Mixed-Mode Loading,” Engineering Fracture Mechanics, Vol. 74, No. 3, pp. 332–345, 2007.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Delbariani-Nejad, A., Nazari, S.A. Effects of loading modes on reliability of cracked structures using FORM and MCS. Int. J. Precis. Eng. Manuf. 18, 63–76 (2017). https://doi.org/10.1007/s12541-017-0008-5
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12541-017-0008-5