Behavior of Concrete Filled Elliptical Steel Tubular Deep Beam under Bending-Shear

The present study aims to investigate, experimentally, the bending shear characteristics of CFEST deep beams through asymmetric four-point loading test method. The selected testing parameters are diameter-to-thickness ratio and two loading directions, namely the major and the minor axes. The results showed that shear capacity of CFEST members is strongly affected by the diameter-to-thickness ratio. The observed failure modes were cracking of the tube and/or shear failure of the in-filled concrete. A method to predict simple shear capacity of the CFEST deep beam is mainly discussed. Additionally, elasto-plastic principal stress behavior of the steel tube is also mentioned.