TY - GEN
T1 - Reliability based design optimization of cantilever beams under fatigue constraint
AU - Honarmandi, Peyman
AU - Zu, Jean W.
AU - Behdinan, Kamran
PY - 2006
Y1 - 2006
N2 - This paper presents a new optimization methodology for reliability design of a prismatic cantilever beam with a point load applied at the tip. In this methodology, the constraints consist of probability failures as well as fatigue failure criteria. The first-order second-moment and first-order reliability methods are adopted to assess the probability failure based on the concept of reliability indices. The corresponding fatigue criterion is defined as the crack initiation phase in both stress and strain models respectively. The elements required for the probabilistic fatigue life calculations are then discussed. In this optimization model, the objective function assumes to be the total beam weight as the quantity of interest However, all geometries, applied loads, and material properties are considered as random variables. The sequential quadratic optimization technique is implemented and a code is developed to solve the nonlinear optimization problem. Results show that using the proposed optimization methodology significantly improves the accuracy of calculation in comparison with using the conventional deterministic analysis. We also conclude that the strain-based fatigue criterion is more realistic than the traditional stress-based analysis. Finally, the Monte Carlo simulation is conducted to validate the results in each case.
AB - This paper presents a new optimization methodology for reliability design of a prismatic cantilever beam with a point load applied at the tip. In this methodology, the constraints consist of probability failures as well as fatigue failure criteria. The first-order second-moment and first-order reliability methods are adopted to assess the probability failure based on the concept of reliability indices. The corresponding fatigue criterion is defined as the crack initiation phase in both stress and strain models respectively. The elements required for the probabilistic fatigue life calculations are then discussed. In this optimization model, the objective function assumes to be the total beam weight as the quantity of interest However, all geometries, applied loads, and material properties are considered as random variables. The sequential quadratic optimization technique is implemented and a code is developed to solve the nonlinear optimization problem. Results show that using the proposed optimization methodology significantly improves the accuracy of calculation in comparison with using the conventional deterministic analysis. We also conclude that the strain-based fatigue criterion is more realistic than the traditional stress-based analysis. Finally, the Monte Carlo simulation is conducted to validate the results in each case.
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M3 - Conference contribution
AN - SCOPUS:34147167131
SN - 1563478080
SN - 9781563478086
T3 - Collection of Technical Papers - AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
SP - 4184
EP - 4196
BT - Collection of Technical Papers - 47th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
T2 - 47th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference
Y2 - 1 May 2006 through 4 May 2006
ER -