Papers by Keyword: Damage Pattern

Abstract: Through accelerated method using external current and 5% Nacl solution, different corrosion results of rebars in columns were attained to study damage patterns of columns under large eccentric loading. Results indicated that columns with different corrosion degree due to different corrosion time developed defferent damage modes. Firstly, results show typically large eccentric damage for columns with different corrosion degree. Secondly, with the increase of corrosion degree, different damage patterns appear under lower loading including reduction of compressive damage scope, expansion of crack zone and earlier crack. These results can be considered as reference to guarantee safety of structures with eccentric loading under corrosion environment.

Abstract: In this paper, the damage patterns of the hexagonal aluminum honeycomb sandwich plate subjected to normal and oblique impact by spherical, cylindrical and cubic fragments at different velocities are simulated using LS-DYNA code. The damage patterns of the sandwich plate and the energy loss ratio of fragment are acquired. In normal and oblique impact for different shapes of the fragment, the damage patterns of the sandwich plate include the plastic deformation, the fracture and the perforation of the face sheet and the tearing of the core or the combination of them. The curve of energy loss ratio waves with the velocity of fragment. And the peak point at the curve of energy loss ratio versus the velocity of fragment denotes the limit velocity of fragment. Furthermore, the energy loss ratios of fragments in oblique impact at the velocity of 500 m•s-1 with the angle of impact of 5°, 10°, 15° and 20° are obtained. The results denote that a fragment with large ratio of length to diameter is easy to perforate the sandwich plate both in normal and oblique impact.

Abstract: The external wall insulation system exposed to the building surface, in summer temperature of outside surface can reach 50 °C -70 °C, this article designs a new external wall insulation system shear strength test of test equipment to study at different temperatures decorative panels sandwich insulation fiber reinforced concrete shear performance, the results show that: with increasing temperature, fiber reinforced concrete decorative panels sandwich insulation ultimate shear capacity has reduced to varying degrees, damage patterns cut from the extruded plate destruction into the adhesive surface of shear failure.

Abstract: A series of formulas about two-parameter parabolic Mohr strength criterion(2-PP Mohr criterion) are derived. Based on the results of uniaxial tension and uniaxial compression tests, the parameters involved in the criterion can be easily determined, then the criterion in terms of the major principal stress and the minor principal stress is derived, and the damage pattern is also discussed. At last, the formulas about the rupture angle and the friction angle are presented, and their relationship is also given. 2-PP Mohr criterion can describe not only shear but also tensile failure. In this criterion the ratio of the uniaxial compression strength and the uniaxial tension strength is not confined as in Griffith criterion. The formula about the rupture angle provides steady theoretical foundation for determining the direction of crack faces and damage patterns in the computation of macro crack propagation. In fact, Griffith criterion is only a special case of the two-parameter parabolic Mohr strength criterion proposed in this present paper.