Research On Combination Of Numerical Integral Method For Substructure Pseudodynamic Testing

The key parts of the structure as experimental substructure are tested large proportionor even full-scale test with explicit numerical integration method, the rest part as numericalsimulation substructure are simulated calculation implicit numerical integration method insubstructure pseudodynamic test. On the one hand,which not only reduces the cost of test,but also the large proportion or even full-scale test can be more reflect the structure of theseismic performance; on the other hand, whose algorithm will be combined the advantagesof not iteration explicit numerical integration method and the advantages of unconditionalstability implicit numerical integration method, which is named combination of numericalintegration method. At present, CD-Newmark Method、PC-Newmark Method and α-OSMethod belong to the combination of numerical integration method, but for others not aredeveloped.The CD-Newmark method is adopted theory of the combination of numericalintegration method, but M. Nakashima found the CD-Newmark method existence problembe strict with time step. In order to solve the problem this paper will firstly be modified theparameters of implicit Newmark-β method of CD-Newmark method, formed the modifiedCD-Newmark method; then, combinated the explicit central difference method (CDM) andimplicit Wilson-θ method and proposed CD-Wilson θ method. The main work and resultsare as follows:(1) The CD-Newmark method is modified and formed the modified CD-Newmarkmethod whose stability and precision is analyzed. The better range of parameter values areobtained by calculation and derivation the stability and precision which can be solve theproblem of CD-Newmark that is strict with time step.(2) In order to find more stable combination of numerical integration method, thepaper will be combinated the explicit central difference method (CDM) and implicitWilson-θ method and proposed the CD-Wilson θ method. In the process of CD-Wilson θmethod research, the Wilson-θ method is modified for getting more stable CD-Wilson θmethod. The result show that the CD-Wilson θ method of stability is better than themodified CD-Newmark method.(3) Some examples are validated more stability the modified CD-Newmark methodand CD-Wilson θ method that are compared to the CD-Newmark method by MATLABprogramming. Verification results show that the modified CD-Newmark method and CD-Wilson θ method of the time step requirement is no longer so strict, the stability rangeof CD-Wilson θ method is bigger than modified CD-Newmark method,...