一种空间全匹配型无限映射单元

根据有限元与无限元的耦合方法，提出了能与空间20节点有限单元相互匹配的三维单向、双向及三向映射无限元坐标函数．无需改变单元形状，采用规则单元划分即可解决三维空间无限域问题，概念上易于接受．对半无限弹性地基问题的沉降计算表明，本文无限元法结果与解析结果有一致的逼近，同等精度要求下较纯有限元法有更高的计算效率；在静态有限元分析中应用该法能以较小的计算区域单元数目满足较高的精度，故具有一定的理论分析和实用价值．

A Mapping Infinite Element with Spatial Whole Matched Type

A mapping function of 3-D single-directional, dual-directional and three-directional infinite elements which can effectively match spatial 20-node finite elements is developed based on the coupling theory of finite and infinite domain. Through the application of regular shape mesh to computational field, the problem about infinite domain will be resolved and the conception can be also accepted easily. With the computational example for a settlement problem of half-space soil, it is indicated that the result obtained by the presented method agree with that by analytical method closely and the coupled infinite-element method have the advantage of the calculating consume than pure finite-element method. Because of more reliable calculation accuracy with less work time by the model, it is of some value in theoretic analysis and practical engineering.