An Engineering Approach to Analyze Damage Initiation Modes in Tapered Composite Structures

In this work an engineering approach is demonstrated for analyzing damage
initiation modes in tapered composite structures. The analysis methodology includes
simulation of the non-linear static response of tapered composite structures under
static tension loads to predict the location of interfacial delamination initiation.
Furthermore, the developed methodology provides a strength-based criterion to assess
whether damage initiation will occur in the inter-laminar delamination or intra-laminar
matrix cracking mode. Based on the results of the analysis, a tapered composite
structure is fabricated and tested under displacement-controlled quasi-static tension
loading. The damage initiation location captured experimentally is compared with the
analysis towards achieving preliminary qualitative validation. The linear stiffness of
the tapered composite structure is predicted within 15% of the experimental average
thereby achieving preliminary quantitative validation.