Analysis of Mechanical Properties of Expansive Concrete Filled Steel Tube with Nonlinear Finite Element Qi Su Zhang Jiru Wang Jiayang Lect.,School of Engineering,China University of Geology,Wuhan 430074,China.The calculating model of expansive concrete filled steel tube is founded by using the principle fundamentals of mechanician. Taking the method of expansive concrete filled steel tube analyzed with nonlinear finite element. It is proved by example that the nonlinear finite element analyzed the mechanical properties of expansive concrete filled steel tube.expansive concrete filled steel tube; concrete; mechanical properte; nonlinear analysis; finite element