参照CECS160(《建筑工程抗震性态设计通则》)和ASCE41(《American Society of Civil Engineers/SEI 41—06》),研究确定拟建的上海中心超高层建筑结构的性能化抗震设计目标,提出了直接用于该结构的基于材料本构关系的性能化抗震设计方法...参照CECS160(《建筑工程抗震性态设计通则》)和ASCE41(《American Society of Civil Engineers/SEI 41—06》),研究确定拟建的上海中心超高层建筑结构的性能化抗震设计目标,提出了直接用于该结构的基于材料本构关系的性能化抗震设计方法,以及基于位移的性能化抗震设计控制指标,选取合适的结构单元模型与合适的非线性动力分析技术相结合的方法,对上海中心超高层结构进行整体抗震性能评估.为该结构设计提供了有益的建议,并为基于位移的性能化抗震设计方法积累了资料.展开更多
We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and me-chanical fields.Based on the basic nonlinear electro-magneto-elastic motion equations for a rectangula...We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and me-chanical fields.Based on the basic nonlinear electro-magneto-elastic motion equations for a rectangular thin plate and the ex-pressions of electromagnetic forces,the vibration equations are derived for the mechanical loading in a steady transverse magnetic field.Using the Melnikov function method,the criteria are obtained for chaos motion to exist as demonstrated by the Smale horseshoe mapping.The vibration equations are solved numerically by a fourth-order Runge-Kutta method.Its bifurcation dia-gram,Lyapunov exponent diagram,displacement wave diagram,phase diagram and Poincare section diagram are obtained.展开更多
This paper presents an efficient time-integration method for obtaining reliable solutions to the second-order nonlinear dynamic problems in structural engineering. This method employs both the backward-acceleration di...This paper presents an efficient time-integration method for obtaining reliable solutions to the second-order nonlinear dynamic problems in structural engineering. This method employs both the backward-acceleration differentiation formula and the trapezoidal rule, resulting in a self-starting, single step, second-order accurate algorithm. With the same computational effort as the trapezoidal rule, the proposed method remains stable in large deformation and long time range solutions even when the trapezoidal rule fails. Meanwhile, the proposed method has the following characteristics: (1) it is applicable to linear as well as general nonlinear analyses; (2) it does not involve additional variables (e.g. Lagrange multipliers) and artificial parameters; (3) it is a single-solver algorithm at the discrete time points with symmetric effective stiffness matrix and effective load vectors; and (4) it is easy to implement in an existing computational software. Some numerical results indicate that the proposed method is a powerful tool with some notable features for practical nonlinear dynamic analyses.展开更多
文摘参照CECS160(《建筑工程抗震性态设计通则》)和ASCE41(《American Society of Civil Engineers/SEI 41—06》),研究确定拟建的上海中心超高层建筑结构的性能化抗震设计目标,提出了直接用于该结构的基于材料本构关系的性能化抗震设计方法,以及基于位移的性能化抗震设计控制指标,选取合适的结构单元模型与合适的非线性动力分析技术相结合的方法,对上海中心超高层结构进行整体抗震性能评估.为该结构设计提供了有益的建议,并为基于位移的性能化抗震设计方法积累了资料.
基金Project(No. A2006000190)supported by the Natural Science Foundation of Hebei Province,China
文摘We studied the problem of bifurcation and chaos in a 4-side fixed rectangular thin plate in electromagnetic and me-chanical fields.Based on the basic nonlinear electro-magneto-elastic motion equations for a rectangular thin plate and the ex-pressions of electromagnetic forces,the vibration equations are derived for the mechanical loading in a steady transverse magnetic field.Using the Melnikov function method,the criteria are obtained for chaos motion to exist as demonstrated by the Smale horseshoe mapping.The vibration equations are solved numerically by a fourth-order Runge-Kutta method.Its bifurcation dia-gram,Lyapunov exponent diagram,displacement wave diagram,phase diagram and Poincare section diagram are obtained.
基金sponsored by the Scientific Foundation for Returned Oversea Scholars of China (Grant No.20101020044)the State Key Laboratory of Hydro–Science and Engineering (Grant Nos. 2008Z6 and 2009-TC-2)
文摘This paper presents an efficient time-integration method for obtaining reliable solutions to the second-order nonlinear dynamic problems in structural engineering. This method employs both the backward-acceleration differentiation formula and the trapezoidal rule, resulting in a self-starting, single step, second-order accurate algorithm. With the same computational effort as the trapezoidal rule, the proposed method remains stable in large deformation and long time range solutions even when the trapezoidal rule fails. Meanwhile, the proposed method has the following characteristics: (1) it is applicable to linear as well as general nonlinear analyses; (2) it does not involve additional variables (e.g. Lagrange multipliers) and artificial parameters; (3) it is a single-solver algorithm at the discrete time points with symmetric effective stiffness matrix and effective load vectors; and (4) it is easy to implement in an existing computational software. Some numerical results indicate that the proposed method is a powerful tool with some notable features for practical nonlinear dynamic analyses.