Strain gage data processing for estimating stress distributions around pipe cross sections.

摘要

This thesis presents a method for estimating the distribution ofstress components around the outer circumference of a cross section ofa pipe, from the readings of strain gage elements arbitrarily positionedand oriented around this circumference. A least-squares procedure isused to obtain best estimates of the coefficients of Fourier expansionsdescribing such distributions. A digital computer program was developedfor applying the method. Data for testing the method and program weregenerated by a computer program using the best available theory of stressanalysis in pipes. Methods for adding random errors to the data wereadapted and used for closer simulation of actual situations. A second problem treated in this thesis is that of inferring theloading acting through the cross section of a straight pipe of concentricbore from known stresses at points on the external surface of thecross section which is presumed to be distant from stress concentrations.It is shown that this inference can be made from stresses atonly three points of the cross section. A digital computer program wasdeveloped to do this.