Study on residual strength of concrete filled steel tube after exposure to explosing impact
The residual bearing mechanism of concrete filled steel tubular beams with different casing hoop steel coefficients after exposure to explosing impact were experimentally investigated. The experiments were carried out on the reaction frame for loading, and the pressure and the residual deformation modes were recorded. The results show that the concrete filled steel tubular beams have good anti-explosion ability and the casing hoop steel coefficient is an important factor to the value of residual strength.
Finite element analysis for CFST columns under blast load
The impact of blast load is always taken into consideration in significant building and protective construction.Presently,concrete filled steel tubular(CFST) is widely used in construction because it has the beneficial qualities of both concrete and steel.In order to study the mechanical behavior of the CFST column under blast load the dynamic responses of a square CFST column under surface explosion were simulated by the nonlinear finite element program ANSYS/LS-DYNA.The JHC model was used for concrete material and the MAT-PLASTIC-KINEMATIC model which accounted for the strain rate used for steel.The failure behavior of the CFST column at scale distance equal to 1.0 was analyzed.The results indicate that the inner concrete was seriously damaged,while the deformation of concrete was restricted by the steel tube.It shows that CFST column has excellent ductility and blast resistance.The time-history curve of displacement of key nodes at different scale distance were compared,which indicates that the deformation of the column obviously decreases with the increase of scale distance.
Analysis of impulsively loaded reinforced concrete structural elements. I: Theory
Abstract A computational approach is presented for the analysis of reinforced concrete beams and slabs under the effects of transient uniformly distributed loads. This approach is based on the Timoshenko beam formulation with non-ideal support conditions. In addition, non-linear material properties, strain are effects, load-reversals, and rational structural behavior models have been included. The solution is achieved by implementing an explicit finite difference formulation. The numerical aspects of the problem are treated and the issue of stability and convergence are addressed.