Damage Development in Bolted Composites with Clearance Subjected to Preload

Abstract

In this study, a damage development process of glass-epoxy laminated composite bolted-joints with bolt/hole clearance under preload moments was investigated. To observe the effects of joint geometry and stacking sequence on the bearing strength and damage mode, parametric studies were performed experimentally. Two different geometrical parameters that were the edge distance-to-hole diameter ratio (E/D) and plate width-tohole diameter ratio (W/D) were considered. Hence, E/D and W/D ratios were selected from 1 to 5 and 2 to 5, respectively. In the meantime, the preload moments on the specimens were also applied as 0, 3 and 6 Nm. Due to observing material parameters effect on damage development, composite laminated plates were stacked three different orientations as [0o/0o/60o/-60o]s, [0o/0o/60o/60o]s and [0o/0o/30o/-30o]s. In addition, the experiments were performed under a clearance for the diameters of the bolt and the circular hole for 5 and 6 mm, respectively. Experimental results point out that failure mode and bearing strength related to damage development are strictly influenced from both material parameters and geometrical parameters. Furthermore, if the preload moments are applied to bolted-joints, the damage mechanism is completely affected from its increasing values

Keywords

• Bolted composites, failure analysis, damage development, fiber reinforced composites

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