Equalizing Octagonal PEC Columns with Steel Columns: Experimental and Theoretical Study

Abstract

Today, the use of composite sections of concrete and steel is increasing. In this study, the behavior of two partially encased composite (PEC) columns is studied experimentally under pure compressive and bending loads. Then a simple analytical method is suggested for PEC columns by introducing all-steel columns, which are composed of four stiffener plates on the four flanges of the steel section. The sizes of the stiffener plates are found by equalizing the compressing strength as well as bending stiffness of the two sections. The accuracy and efficiency of the suggested method was assessed using the FEM in a software program by calculating and comparing the internal forces resulting from analyzing an irregular building. The results indicated high accuracy of the suggested linear static analysis method and meet the need to use finite-element simulations for the users and designers.