Residual Strength Evaluation for Aerospace Composite Structures with Large Notch Damage in MSC.Nastran SOL 700 Advanced Composite based on Alphastar GENOA Software

Large notch damage usually consists of failed or completely severed stiffeners or spars, or chord with failed or completely severed attached skin or web. Large notch damage results from unknown damage sources so the damage event is immediately obvious to the flight crew. The airplane must be capable of successfully completing a flight with such damage. The determinate accidental damage event is to ensure a balanced design approach in which the damage size in linked to the structural configuration. The criterion that is generally used, called the “two bay crack criterion,” states that the damage tolerant composite structure should sustain the regulatory loads with damage in skin like sharp slit or notch which extends two adjacent bays with severed center stiffener. For this damage state, any structural design must demonstrate the residual strength load capability not less than as defined in the regulations. In order to reduce costs and product lead-time, Virtual Testing (VT) can be used to reduce the scale of physical testing necessary for structures development and certification. Virtual Testing involves an accurate simulation of physical tests using multi-scale Progressive Failure Analysis. In this paper residual strength evaluation for composite structures with large notch damage using MSC.Nastran SOL 700 advanced composite based on AlphaSTAR GENOA Software has been investigated. Accurate prediction of failure of all structural aerospace component is crucial in order to achieve the goal of weight minimization, material savings and improved performances. MSC software provides a very convenient solution to perform complex analyses of the aerospace structure as well as for nonlinear analysis including materials and large deformations and strains. Using this tool we are able to optimize configuration and complete the design in less time than have been required using traditional design methods. In this paper an example will be shown, comparing a virtual and real testing of an aerospace composite stiffened reinforced panel.