Abstract：In view of different requirements of 3-D model building, appearing various kinds of 3-D model-building software, the paper presented a TIN-pieces processing-based structural model-building technique that uses 3-D CAD design idea, and a variety of 3-D interactive tools to edit TIN-pieces and construct the layers and fault planes, finally build up a structural model conforming to the demands. This is an incremental flexible dynamic model-building approach, in which the user can make real-time modification in any stage of model building and utilize variable algorithms and 3-D interactive visualization tools in maximum. The key of approach is on strengthening the TIN-pieces processing and highlighting the advantage of 3-D interactive tool combining with algorithm, which makes the description of complex structures become easier, which other algorithms are difficult to describe.
