Date of Award
Master of Science in Engineering
Mechanical and Aerospace Engineering
Mechanical and Aeronautical Engineering
Dr. Daniel Kujawski
Dr. Judah Ari-Gur
Dr. Philip Guichelaar
Masters Thesis-Open Access
In damage tolerant designs, it is important to know the crack growth behavior of a material, so that sudden failure of a component can be avoided by determining a safe life. There are numerous models available to predict the crack growth rate. Among them the "crack closure model" is most often used for predicting the crack growth rate for different R-ratios and load interaction effects. However recently, the crack closure model has come under criticism by many authors to be flawed and overrated owing to its inherent drawbacks.
Therefore, a mathematical model for the fatigue crack propagation based on damage accumulation process ahead of the crack tip has been developed, which utilizes stress and strain distribution ahead of the crack tip, modeled using Rice and elastic solutions. The methodology is based on the use of both Kmax and ∆K as contributing parameters to the driving force and damage accumulation.
Weight function approach has been adopted to determine the Kres profile. Load interaction and overload effects have been modeled by the effect of Kres on the Kmaxand ∆K. The predictions made by the model have been compared to experimental data and reasonable agreement has been found.
Goswami, "Prediction of Crack Growth Rate and Load Interaction Effects using Damage Accumulation Model" (2004). Master's Theses. 4753.