چکیده مقاله
The stress intensity factor SIF is one of the crucial parameters in evaluating the fatigue reliability of offshore tubular joints based on the fracture mechanics FM approach The value of SIF is a function of the crack size, nominal stress, and two modifying coefficients known as the crack shape factor Yc and geometric factor Yg These coefficients exhibit considerable scatter which calls for greater emphasis in accurate determination of their governing probability distributions As far as the authors are aware, no comprehensive research has been carried out on the probability distribution of geometric and crack shape factors in tubular joints What has been used so far as the probability distribution of these factors in the FMbased reliability analysis of offshore structures is mainly based on assumptions and limited observations, especially in terms of distribution parameters In the present paper, results of parametric equations available for the computation of Yc and Yg have been used to propose probability distribution models for these factors in tubular K joints under balanced axial loads Based on a parametric study, two samples were prepared for Yc and Yg; and the density histograms were generated for these samples using Freedman Diaconis method Ten different probability density functions PDFs were fitted to these histograms The maximum likelihood ML method was used to determine the parameters of fitted distributions In each case, Kolmogorov Smirnov test was used to evaluate the goodness of fit It was concluded that Birnbaum Saunders and Gamma distributions are the best probability models for the geometric and crack shape factors in tubular K joints under balanced axial loads, respectively
کلیدواژهها
نویسندگان
حمید احمدی
Faculty of Civil Engineering, University of Tabriz, Tabriz ۵۱۶۶۶۱۶۴۷۱, Iran
Amirreza Ghaffari
Faculty of Civil Engineering, University of Tabriz, Tabriz ۵۱۶۶۶۱۶۴۷۱, Iran
شیوه ارجاع
Ahmadi, Hamid and Ghaffari, Amirreza,1394,Probability distribution models for geometric and crack shape factors of SIFs in tubular K-joints under balanced axial loads,10th International Congress on Civil Engineering,Tabriz
ارائهشده در
مجموعه مقالات دهمین کنگره بین المللی مهندسی عمران15 اردیبهشت 1394 · تبریز