NEW STRENGTH-BASED MODEL FOR THE DEBONDING OF DISCONTINUOUS FIBERS IN AN ELASTIC MATRIX

The mechanical properties of fibre composites are strongly influenced by the debonding of fibres. When an embedded fibre is loaded from one end, debonding can occur at both the loaded end and the embedded end. Existing theories neglect the possibility of debonding from the embedded end and are thus limited in applications to cases with low fibre volume fraction, low fibre modulus or short fibre length. A new two-way debonding theory for fibre debonding, which can extend the validity of one-way debonding theory to all general cases, is therefore proposed. Based on the new theory, different scenarios of debonding are identified. Comparison is made between results predicted by the new two-way theory and a one-way debonding theory. The relative merits and dismerits of strength-based debonding theories compared to fracture-based debonding theories are briefly discussed.