Transient delamination growth in GFRP laminates with fibre bridging under variable amplitude loading in G-control

To predict fatigue-driven delamination growth in real structures, it is inevitable to understand under load spectra, also known as in-service loads, which most commonly are variable amplitude patterns. In this work, glass fibre-reinforced polymer laminates subjected two-level block loading investigated using a pure moment loaded DCB test configuration for G-controlled cyclic testing. The patterns consist of single- and periodic repeated changes. method utilises digital image-based technique that allows precise tracking fronts translucent materials. work characterises transient crack phenomena following changes with emphasis on the actual fatigue rate. may increase rate by factors 5–6 comparison constant base-line tests. Periodic particularly growth. For example, after just 10 low- high-load blocks, has extended more than factor 2 times extension predicted from non-interaction model based data. effect frequency investigated. Frequent proven significantly because responses