Modeling of Ultra-high Performance Fiber Reinforced Concrete Filled Steel Tube Columns under Eccentric Loading

Recently, ultra-high performance fiber reinforced concrete (UHPFRC) has been commonly used as a structural material. In this study, finite element (FE) model is constructed to investigate the behavior of filled steel tube columns (UHPFRCFSTs) under axial or eccentric loading. The analysis included three-dimensional FE using solid elements. novelty suggested consideration confinement UHPFRC in-filled Furthermore addition, numerical includes initial local and overall geometric imperfections, well inelastic response both materials. interaction between modelled surface contact. Experimental results from literature are validate model. It proved that can predict ultimate capacities, failure modes, post-cracking accurately for short long UHPFRCFSTs. diagram agreed very with experimental results. Using verified model, parametric study on UHPFRCFSTs carried out. Several parameters, including strength material, yield strength, aspect ratio (column diameter/tube thickness), investigated. Eventually, comparisons conducted obtained simulation existing design codes predicting load-moment found Eurocode 4 predictions in most analyzed cases conservative