Homogenised non-linear soft inclusion for simulation of impact damage in composite structures

This paper presents the development of a homogenised non-linear soft inclusion which captures the geometric and material non-linearity of impact damage zone loaded in tension and compression. The homogenised non-linear soft inclusion can present a conservative worst case damage zone or use experimental data to mimic the behaviour of a particular damage zone in a simple and computationally efficient way that can be used as a structural design tool for composite structures subjected to impact. The development of the non-linear soft inclusion, implemented in an ABAQUS/Explicit VUMAT, is presented at element and coupon level. The non-linear soft inclusion is validated against experimental coupon data and produces a conservative worst case estimate in all cases investigated.