Underlying fracture trends on Mode-I crack multiple-branching

An energy-based modelling has been proposed to capture the physical process of multiple cracks initiation from a Mode-I crack tip. The underlying fracture trends and instability on crack tri-branching, symmetric branching and side-branching induced by dominant Mode-I loading are formulized. The solutions of the energy release rate, crack initiation angles and K-based fracture criterion for multiple cracks initiation have been investigated. The upper limit on the number of possible crack initiation is given for a Mode-I crack. The discussions in present article indicate that some underlying fracture configurations for Mode-I crack can be triggered by using impulse loading. Many fracture behaviours for a Mode-I crack can be better explained and understanding based on the present theoretical modelling. The fracture toughness predicted by the present modelling and Griffith's criterion agree well with experimental results.