Abstract

An efficient algorithm to characterize experimental stress-strain data is preacated. The algorithm segments the curve into regions by locating regions with a maximum correlation coefficient. Thus the algorithm determines the initial region of the curve to be considered in determining the initial slope or, in the case of a stress versus strain curve, the initial modulus. The algorithm is of particular use in analyzing the elastic behavior of composites where nonlinear stress-strain, knees, damage, and other abnormalities may occur. The results of the algorithm are compared to linear regions determined from calculations of correlation coefficients involving all possible regions within a data file. In general, the algorithm provides the same linear regions as are determiend from the complete calulation of correlation coefficients and is at least one order of magnitude faster.

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