Since most current seismic capacity evaluations of reinforced concrete （RC） frame structures are implemented by either static pushover analysis （PA） or dynamic time history analysis, with diverse settings of the p...Since most current seismic capacity evaluations of reinforced concrete （RC） frame structures are implemented by either static pushover analysis （PA） or dynamic time history analysis, with diverse settings of the plastic hinges （PHs） on such main structural components as columns, beams and walls, the complex behavior of shear failure at beam-column joints （BCJs） during major earthquakes is commonly neglected. This study proposes new nonlinear PA procedures that consider shear failure at BCJs and seek to assess the actual damage to RC structures. Based on the specifications of FEMA-356, a simplified joint model composed of two nonlinear cross struts placed diagonally over the location of the plastic hinge is established, allowing a sophisticated PA to be performed. To verify the validity of this method, the analytical results for the capacity curves and the failure mechanism derived from three different full-size RC frames are compared with the experimental measurements. By considering shear failure at BCJs, the proposed nonlinear analytical procedures can be used to estimate the structural behavior of RC frames, including seismic capacity and the progressive failure sequence of joints, in a precise and effective manner.展开更多
The non-uniqueness of the transition from nonobjective constitutive relations to objective ones with the use of the principle of material frame-indifference(PMFI)is shown.To eliminate it,the concept of finite strain w...The non-uniqueness of the transition from nonobjective constitutive relations to objective ones with the use of the principle of material frame-indifference(PMFI)is shown.To eliminate it,the concept of finite strain without rotations(FSWR)for a given material type and each strain component(elastic,plastic) is introduced.In FSWR the rotation is excluded with respect to the natural preferred configuration for a given material.Considered are a simple solid,a liquid,a mouocrystal,a polycrystal and a composite.The procedure is proposed lbr consistent generalization of known infinitesimal relations for finite strains and rota- tions.The structure of constitutive relations is derived for anisotropic elasto-plastic mono-and polycrystalline materials.展开更多
文摘Since most current seismic capacity evaluations of reinforced concrete （RC） frame structures are implemented by either static pushover analysis （PA） or dynamic time history analysis, with diverse settings of the plastic hinges （PHs） on such main structural components as columns, beams and walls, the complex behavior of shear failure at beam-column joints （BCJs） during major earthquakes is commonly neglected. This study proposes new nonlinear PA procedures that consider shear failure at BCJs and seek to assess the actual damage to RC structures. Based on the specifications of FEMA-356, a simplified joint model composed of two nonlinear cross struts placed diagonally over the location of the plastic hinge is established, allowing a sophisticated PA to be performed. To verify the validity of this method, the analytical results for the capacity curves and the failure mechanism derived from three different full-size RC frames are compared with the experimental measurements. By considering shear failure at BCJs, the proposed nonlinear analytical procedures can be used to estimate the structural behavior of RC frames, including seismic capacity and the progressive failure sequence of joints, in a precise and effective manner.
文摘The non-uniqueness of the transition from nonobjective constitutive relations to objective ones with the use of the principle of material frame-indifference(PMFI)is shown.To eliminate it,the concept of finite strain without rotations(FSWR)for a given material type and each strain component(elastic,plastic) is introduced.In FSWR the rotation is excluded with respect to the natural preferred configuration for a given material.Considered are a simple solid,a liquid,a mouocrystal,a polycrystal and a composite.The procedure is proposed lbr consistent generalization of known infinitesimal relations for finite strains and rota- tions.The structure of constitutive relations is derived for anisotropic elasto-plastic mono-and polycrystalline materials.
