To overcome overly-stiff property existing in the widely used finite element method(FEM)with linear triangular elements
which generally leads much higher natural frequency
the cell-based smoothed point interpolation method(CS-PIM)with condensed shape functions is applied to structural dynamic analysis. Adopting the condensed shape function constructed with the new scheme of virtual nodes arrangement
which increases the accuracy of shape functions
the present method can avoid the temporal instability problems
including the much lower natural frequency and spurious natural mode caused by the overly-soft property in CS-PIM using traditional virtual nodes arrangement. In the present method the simple linear triangular mesh can automatically discretize the domain. This method can provide stable and highly accurate solutions to dynamic analysis of complex engineering structures.
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