摘要
该文采用最简单的Galerkin型线性单元,对运动方程构建了简捷高效的单步法递推公式;进而基于EEP超收敛计算技术,开发了单元步长自动优化和结点位移精度修正两项关键技术,可在整个时域上得到误差分布均匀且逐点满足给定的误差限的解答——堪称数值解析解。该文给出了单自由度和多自由度的数值算例以验证本法的有效性。
This paper uses the simplest linear finite elements of the Galerkin type and gives a compact and efficient recurrence solution formula for equations of motion. Further, based on the EEP(Element Energy Projection) super-convergence technique, two critical techniques, i.e. adaptive time-step size and recovery of nodal displacement accuracy, have been developed, enabling a linear finite element solution with errors uniformly distributed and satisfying the pre-specified error tolerance at any moment in the whole time domain. Numerical examples of both single and multiple degreed systems are given to verify the validity of the proposed method.
引文
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该文在第26届结构工程学术会议(2017长沙)应邀作特邀报告