# Static Strength and Buckling Analysis of an Aircraft Support

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Methods

## 3. Strength Test Fixture

## 4. Strength Analysis

#### 4.1. Numerical Analysis Model of Strength Analysis

#### 4.2. Numerical Results of Strength Analysis

#### 4.3. Strength Test and Comparison

## 5. Buckling Analysis

#### 5.1. Linear Eigenvalue Buckling Analysis

#### 5.2. Nonlinear Buckling Analysis

## 6. Discussion

- (1)
- Strength test specification with 30.151 KN test load is used for strength analysis, and a reasonable strength test fixture is designed and manufactured. Numerical analysis results show that the stress level of the bearing area of the bearing component is about 425.3 Mpa, which is less than the yield strength of the material. Comparing the experimental value of the selected strain sensor S6 position with the numerical analysis results, the error is within 2.5%, indicating the effectiveness of the numerical analysis, and the structural strength of the bearing parts meets the requirements and has certain static strength stability. The stress value of the connection area of the test piece exceeds the yield strength ${\sigma}_{0.2}$, and strain of edge of the test piece is larger than other areas can be the further optimally designed in terms of structure strength.
- (2)
- The linear eigenvalue buckling analysis is used to solve the first six buckling orders of the bearing assembly, and the first-order buckling mode and the corresponding critical load 464.9 KN are obtained, respectively. The critical load value is the load value of nonlinear buckling through reference. The disturbance value is introduced in the nonlinear buckling analysis, and the critical load values of nonlinear buckling without perturbation, 1% initial imperfection, and 10% initial imperfection are 110.6 KN, 108.4 KN, and 106.2 KN, respectively. The three are about 1/4 of the critical load value of linear eigenvalue buckling, but the three critical load values are not much different, indicating that the geometric imperfections of the bearing parts are not obvious for nonlinear buckling and have certain structural stability. When the load exceeds the critical load value of nonlinear buckling, the displacement deformation of the bearing area reaches 21.4 mm, and the structure enters the instability state, indicating the necessity of considering nonlinear buckling analysis.
- (3)
- The strength test load, 30.151 KN, is about 27.3% of the critical load of nonlinear buckling, 110.6 KN. By analyzing the load loading of this large span, the stress range and deformation of the structural strength performance and the instability of the bearing member are summarized, which can provide the reference for the structural strength optimization design of the bearing member by using strength analysis and buckling analysis.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

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**Figure 10.**Buckling analysis curve. A is the linear eigenvalue buckling value, B is the nonlinear buckling value.

Part | Type | Shape | Amount |
---|---|---|---|

Fixture | 3D Stress | Hex | 23,844 |

Pad | 3D Stress | Hex | 1210 |

Support | 3D Stress | Hex and Tet | 13,906 |

38,960 |

Part | E (GPa) | ${\mathit{\sigma}}_{0.2}\left(\mathbf{MPa}\right)$ | ${\mathit{\sigma}}_{\mathit{b}}\left(\mathbf{MPa}\right)$ | µ |
---|---|---|---|---|

Fixture | 200 | 835 | 1080 | 0.3 |

Pad | 70 | 275 | 425 | 0.34 |

Support | 71.7 | 540 | 582 | 0.33 |

Load/% | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 |
---|---|---|---|---|---|---|---|---|

Value/N | 1508 | 3015 | 4523 | 6030 | 7538 | 9045 | 10,553 | 12,060 |

Load/% | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |

Value/N | 13,568 | 15,076 | 16,583 | 18,090 | 19,598 | 21,106 | 22,613 | 24,121 |

Load/% | 85 | 90 | 95 | 100 | ||||

Value/N | 25,628 | 27,136 | 28,643 | 30,151 |

D_{min} (mm) | D_{max} (mm) | D_{mid} (mm) | D_{m} (mm) | |
---|---|---|---|---|

1 | 3.411 | 17.723 | 5.002 | 4.979 |

2 | 3.396 | 17.704 | 5.037 | 5.011 |

3 | 3.421 | 17.733 | 4.994 | 4.882 |

mean value | 3.409 | 17.720 | 5.011 | 4.957 |

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**MDPI and ACS Style**

Zhang, D.; Zhang, G.; Chen, Y. Static Strength and Buckling Analysis of an Aircraft Support. *Appl. Sci.* **2023**, *13*, 4362.
https://doi.org/10.3390/app13074362

**AMA Style**

Zhang D, Zhang G, Chen Y. Static Strength and Buckling Analysis of an Aircraft Support. *Applied Sciences*. 2023; 13(7):4362.
https://doi.org/10.3390/app13074362

**Chicago/Turabian Style**

Zhang, Daqian, Guoxiong Zhang, and Yueyang Chen. 2023. "Static Strength and Buckling Analysis of an Aircraft Support" *Applied Sciences* 13, no. 7: 4362.
https://doi.org/10.3390/app13074362