Numerical analysis of a new mixed mode I/III fracture test specimen

• A new test sample called the ENDB specimen was suggested for mixed mode I/III fracture studies.
• Fracture parameters of the ENDB specimen were obtained numerically for various geometries and loading conditions.
• The ENDB specimen can introduce full combinations of mode mixities including pure modes I and III.
• At the mid-section of specimen KII is zero but KI and KIII attain their maximum values.

A new test configuration called the edge notched disc bend specimen is suggested for investigating mixed mode I/III fracture behavior. The proposed specimen is a circular disc containing an inclined edge crack thorough the diameter and is subjected to three point bend loading. Extensive three dimensional finite element analyses were performed for different geometrical parameters and loading conditions to obtain the stress intensity factors and the T-stress in the proposed disc bend specimen. The finite element results showed that the suggested specimen is able to introduce full combinations of mixed mode I/III ranging from pure mode I to pure mode III.