OPTIMIZATION OF RE-PROFILING ROUND PIPES INTO RECTANGULAR ONES FOR BEAM STRUCTURES

Abstract

The article presents a new method of converting round pipes into rectangular ones where the width to the height is 1:3 along the median line of the design section. It maximizes their bending bearing capacity. The calculation of optimal parameters of thin-walled rectangular cross sections is given according to the approximate method, the correctness of which is confirmed by testing the used standard profiles. The entire diagram of changes in the design parameters of rectangular pipes during the transformation of their cross sections from vertical to horizontal configurations, including the transition through the outline of a square shape, is shown. A comparative analysis of optimized cross-sections of oval, plane-oval, semi-plane oval and rectangular pipes, taking into account their elastic deformations, is performed. It is once again noted that in order to achieve the greatest bearing capacity for bending oval profiles, as well as all others, it is not permissible to re-profile round pipes with an increase in the length of the middle lines of their cross-sections. The choice in favor of rectangular profile pipes is justified due to their simpler shape, including only plane faces (vertical and horizontal), relatively low cost, lower height, greater compactness, increased moment of resistance.