An analytical model for the prediction of through-thickness stiffness in tension-loaded composite bolted joints

Based on the acoustoelasticity theory, a certain relationship exists between ultrasonic velocity and stress. By combining shear and longitudinal waves, this paper provides a nondestructive method of evaluating axial stress in a tightened bolt. For measuring the bolt axial stress in different situations, such as under low or high loads, this paper provides guidelines for calculating the stress for a given load factor. Experimental and calculated results were compared for three bolt test samples: an austenitic stainless steel bolt (A2-70) and low-carbon steel 4.8 and 8.8 bolts. On average, the experimental results were in good agreement with those obtained through calculations, thus providing a nondestructive method for bolt stress measurements.

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Characteristic Evaluation on Bolt Stress by Ultrasonic Nondestructive Methods

Analysis of elastic interaction stiffness and its effect on bolt preloading

Traction-based multi-scale nonlinear dynamic modeling of bolted joints: Formulation, application, and trends in micro-scale interface evolution

Dynamic investigation of aeroengine high pressure rotor system considering assembly characteristics of bolted joints

An improved stiffness model is proposed for bolted joints made of similar and dissimilar plates. A novel approach is used to obtain an expression for the effective area used for determining the joint stiffness. More accurate estimate of the joint stiffness provides a more reliable prediction of the joint behavior both during its initial assembly, as well as under subsequently applied tensile loads in service. The effect of the grip length-to-diameter ratio, joint sizes, underhead contact radii ratio, hole clearance, and plate material/thickness ratio are investigated. Experimental data are used for determining the envelope angle a in the proposed analytical model. Finite element modeling is used for evaluating the accuracy of the proposed stiffness model.

Antoine Abboud

Papers

An Improved Stiffness Model for Bolted Joints

Viscoelastic Strain Hardening Model for Gasket Creep Relaxation