Partially Encased Composite Column Response Using Different Types Of Plate Thickness And Transverse Link Under Axial Load

Abstract

There are two types of composite columns, concrete encased section, and concrete-filled steel tube which are commonly used in buildings. Concrete Encased Steel (CES) composite columns have been of interest to many researchers due to their excellent structural performance under both static and seismic loading conditions. Concrete encased steel (CES) composite columns can be divided into two categories: Fully Encased Composite (FEC) column and Partially Encased Composite (PEC) column. This study focused on the PEC column response by using different types of plate thickness and transverse link under axial load. In partially encased composite column, the steel flange is not externally restrained by the concrete so, it may deform outwards. The analysis was performed by the finite element analysis (FEA) software package ABAQUS 6.14. The geometric parameters for the study were the thickness of H-section, and transverse link arrangements. A parametric investigation procedure was done on a series of fourteen (14) samples column. The study considered H section with a thickness of web (from 7.2mm to12.7mm), thickness of flanges (from 11mm to 20.5mm), and link shapes (horizontal, X-shape, and Z-shape). The result from the study shows the capacity of partially encased composite column increase with the decrease of effective width to the thickness of flange (b/T) or effective width to thickness of web (b/t). The peak capacity of C-5 specimen is 38.37 % higher than the peak capacity of C-1 specimen when the b/T ratio decreased from 9.5 to 5.1. As the b/t ratio is reduced from 14.5 to 8.2 the axial load capacity of PEC columns was increased by 32 %. The transverse link increases the axial capacity of the partially encased composite (PEC) column. From three types of link arrangement X-shape link has 38.72 % and 16.75% higher peak load capacity than horizontal and Z-shape link respectively.