Correction response surface approximations for stress intensity factors of a composite stiffened plate

Roberto Vitali, Raphael Haftka, Bhavani Sankar
1998 39th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference and Exhibit   unpublished
A comparison between two methods of employing response surface techniques to predict stress intensity factors (SIF) in cracked composite panels is presented. The first method uses the values of SIF obtained from a highfidelity method of analysis to estimate the SIF at other points of the design space. The second method fits a quadratic response surface to the ratio of SIF obtained from the high-fidelity method and a lower-fidelity method. The value of SIF at other design points is then found
more » ... ts is then found multiplying the ratio by the SIF given by the low-fidelity method. This second method proves to be more accurate especially when the value sought lays outside the design space. Moreover a method to calculate the SIF in the zero-deg plies of a laminate from the equivalent orthotropic laminae is presented.
doi:10.2514/6.1998-2047 fatcat:rhehj5vd4jez7hnzqrpopoo6mu