Unlike hole coaxiality or other drilling defects, misalignment has never been a major concern in aeronautical structures as perfect bolt-hole alignment was ensured through the global assembly process. However, new industrial philosophy called hole-to-hole, which aims to decrease cost and time an unavoidable effect. A number of numerical studies have investigated load distribution among fastener...

An experimental study into the structural behaviour of Directed Energy Deposition-arc or wire arc additively manufactured (DED-arc AM and WAAM, respectively) steel double-lap shear bolted connections is presented. The mechanical properties material, which had a nominal yield stress 420 MPa, were first determined by means tensile coupon tests. Sixty connection specimens two different thicknesses...

Bolted joints are prevalent in most assembled structures; however, predictive models for their behavior do not exist. Calibrated models, such as the Iwan model, are able to predict the response of a jointed structure over a range of excitations once calibrated at a nominal load. The Iwan model, though, is not widely adopted due to the high computational expense of implementation. To address thi...

During maintenance operations, technicians have to work as quickly as possible. But they are often stopped during disassembly by blocked bolts or studs. This paper examines causes of blockage and suggests new method for disassembling bolted joint in this case. Several methods are analyzed and tested with finite element simulations. An experimental protocol to test a new disassembling method is ...

Bolted joints are generally used to connect two or more mechanical structures due their ease of assembly and disassembly for maintenance. However, the problem vibration is one main challenges when tightness bolted insufficient, causing failures such as looseness resulting in disconnection. Looseness most common cause dynamically loaded joint structure failure. This study tested a simple bolt ob...

This paper presents both experimental and numerical studies on bolted glass fiber reinforced polymer (GFRP) joints subjected to uniaxial tension different thermal conditions (?20 ?, 20 ? 60 ?). Laboratory tests are conducted obtain strength, elastic modulus deformation of the joints. The model is developed using discrete element method (DEM) that can predict not only above properties joints, bu...

AMPTIAC Directory ... 15 The beginning In late 1993, the Mechanics and Surface Interactions Branch of the Air Force Research Laboratory’s Materials Directorate (AFRL/MLBM) was tasked to investigate the accuracy of the analysis methods used to predict the strength of bolted composite joints used on high-performance fighter aircraft such as the F-22 Raptor. The strength of bolted joints is essent...