Adhesively bonded joints as a dissipative energy mechanism under impact loading

Abstract

a b s t r a c tThe use of adhesives as a bonding system in aircraft construction has increased because of its structural efficiency, simplicity and lightness. New aircrafts are designed taking into account, among other criteria, security standards in case of crash or fall. For an aircraft, security techniques in case of collision can be defined as the internal system capability to prevent the passengers from being injured in an impact. A proactive proposal is to mitigate the impact energy absorbed by the passengers, by means of increasing as much as possible the capacity of the aircraft to capture energy. In this work, we suggest taking advantage of the energy that could be dissipated by the structural bonded joints due to their debonding process. We propose to optimise the geometry of the adhesive assembly in order to increase the amount of energy dissipated due to the damage of the adhesive during the crash. The scope is to define the best geometrical configuration of the joint to dissipate the largest amount of energy with safety purposes. To this aim, we study the behaviour of a bonded joint of two composites submitted to impact loading by means of the Finite Element Method.

Cohesive zone models and impact damage predictions for composite structures

“…Fiber failures can also be modeled by cohesive elements. In a series of articles, Bouvet et al [199,[232][233][234] use cohesive elements to High velocity impact [201,275,372,373] Soft impact [202,[254][255][256] Crushing tube [203,326] Crushing plate [349,350] Energy absorbing structures [338,339,374] predict both intraply and interlaminar damage during low velocity impacts. This approach was also used to study the compression after impact behavior of laminates [235].…”

Dynamic properties and plastic dissipative mechanisms of polymeric adhesive under dynamic compression at various strain rates

“…An ideal energy-absorbing adhesive is needed to dissipate the impact energy while keeping the force on it below some limit to maintain the structural integrity. The study of the energy dissipation in polymers during impact was the subject of several publications 3,7,10,16,17 and corresponded to internal heating caused by polymer plasticity and the fracture process. The heat dissipation can cause an increase in temperature since the dynamic deformation occurred over short time scales, thermal conditions being essentially adiabatic.…”

Static and Fatigue Characterization of Adhesive T-Joints Involving Different Adherends

“…Finally, in terms of aeronautic applications, T-joints are very favorable due to their structural efficiency, simplicity, and lightness. In this context, Moreno et al [12] proposed a system to take advantage of the energy that could be dissipated by the structural bonded joints.…”