08.35: Compressive behavior of concrete filled double skin sections consisting of corrugated plates and ultra‐high strength steel corner tubes

Abstract

ABSTRACTConcrete filled tubular (CFT) sections and the most recent configuration of these sections, concrete filled double skin tubular (CFDST) sections, are being increasingly utilized in structural constructions due to their high strength and great performance under fire. CFDST sections generally consist of two steel hollow sections where the gap between the steel skins is filled with concrete. In this study, the mechanical performance of a new type of CFDSTs consisting of corrugated steel skins and ultra‐high strength steel (UHSS) or mild‐steel (MS) corner tubes is investigated. The efficiency of corrugated skins and UHSS or MS corner tubes is experimentally examined through conducting monotonic compressive tests. It is shown that employing steel skins with corrugated geometry may significantly increase the post‐peak compressive strength of CFDST sections. In addition, the experimental results are revealed that the non‐ductile compressive behaviour of ordinary CFDST sections can be effectively improved by employing UHSS corner tubes in fabrication of these sections. A finite element modelling framework is also developed to simulate the behaviour of the proposed high strength corrugated CFDST columns. The numerical modelling is first validated against the experimental results. The outcome of the paper indicates the potential of corrugated CFDSTs with UHSS or MS corner tubes to be used in various civil engineering construction.