Impact Compression Test and Numerical Simulation Analysis of Concrete after Thermal Treatment in Complex Stress State.

摘要: To study the dynamic mechanical properties and fracture law of concrete after thermal treatment reveal its mechanism, impact compression test was carried out on different thermal-treated (400-800 °C) specimens using a split Hopkinson pressure bas (SHPB) system. By ANSYS/LS-DYNA, finite element numerical simulation process illustrated. The research showed that under passive confining pressure, more loading rate is increased, obvious effect specimen, as well significant improvement peak stress compared with uniaxial test. On other hand, temperature damage enhanced, increase in material strength at rates reduced. Numerical simulations test, increases, crack initiation time advances, degree increases same time. In case gradually decreases to edge from center, has circumferential diffusion characteristic. restraint limits radial deformation ability certain extent, thereby increasing axial compressive strength. analysis crushing specimens, it found form strong dependence. When low, cleavage-like failure. As changes crush results provide necessary theoretical basis for safety assessment, reinforcement, maintenance structures fire.