A Semi-Analytical Approach for Predicting the Stresses and Failure Modes of Composite Lugs

Lugs are a specific type of joint with a semi-circular geometry around the pinhole utilized in the aerospace field. Its distinct geometry and ability to carry loads in its plane make it a very common choice for design engineers. Although this type of joint is widely used, there are no analytical equations that can predict the stresses around the...

Design of pin connections between steel members

The design of pin connections between steel members has been established for many years in design codes. However, recently, in the scope of the revision of Eurocode 3, Part 1–8 (EN 1993–1-8), questions were raised concerning the safety of the corresponding design verifications. This paper identifies two main aspects that require revision,...

Methodology for Prediction of the Fatigue Life for Lug Joints Subjected to Combined In-Plane and Out-of-Plane Loading

New methods for aircraft movables introduce oblique- and out-of-plane loads on lug joints. With the introduction of these loads on lugs the need arises for a more detailed fatigue life prediction method. <br/><br/>Therefore, the thesis research focused on creating a methodology for predicting the fatigue life for lug joints subjected to combined...

Investigation of the Application of adhesively bonded lifting lugs in ship building

Defects are produced when lifting lugs being welded on ship sections during the building process. The large amount of heat produced in the welding work causes “heat affected zone” in the base metal on sections and destroys painted coatings on the plates; and residual stress decreases the mechanical performance of the steel plates. To eliminate...

Flight simulation fatigue crack propagation in single and double element lugs

Flight simulation fatigue crack propagation tests on single and double element lugs made from 2024-T351 and TOT5-TT351 aluminium alloys and Ti-6AJ.-UV titanium alloy were carried out. Initial damage was a throughthickness notch at one side of each hole in one element. Results showed that crack propagation lives for double element lugs were much...

Lifetime prediction methods for corner cracks at holes

An application of linear elastic fracture mechanics to 3-dimensional crack growth prediction was developed in two phases. In the first phase finite element techniques for accurate stress intensity (S.I.) calculation were evaluated and the Virtual Crack Extension (V.C.E.)-method was selected for further work. In the second phase the process of...

Application of finite element methods to the analysis of cracks: final report

The applicability of finite element methods to the analysis of cracks was studied in three phases. In the first phase the available methods for the calculation of elastic stress intensity data for cracks of arbitrary shape using finite element techniques were evaluated. The indirect energy release method using virtual crack front variation was...