基于GTP的地下工程与围岩一体化真三维空间构模

针对地下工程开挖体的基本特征及其真三维建模要求，在广义三棱柱(GTP)模型的基础上进行扩展，提出采用E—GTP模型来构建地下工程开挖体的真三维模型。通过与其围岩地质体的G—GTP模型的耦合，实现了基于GTP的工程开挖体与围岩地质体的一体化建模。该模型将地下三维空间实体抽象为点、线、面、体四类对象，通过结点、TIN边、侧边、TIN面、侧面和GTP体元共6个基本几何元素进行统一表达。该文重点讨论了E—GTP的建模原理与方法，并介绍了基于面向对象思想的一体化空间数据结构。

GTP-based Integral Real-3D Spatial Modeling for Subsurface Engineering and Its Surrounding Geology Bodies

2 . Advanced Research Centre for Spatial Information Technology, LSGI, Polytechnic University of Hong Kong, China ) In consideration of the basic features of subsurface engineering excavation and the demands for real three dimension (3D) spatial modeling, an engineering GTP (E -GTP) model, as a special instance of generalized tri -prism (GTP) model, is presented to model the subsurface engineering excavations in real - 3D. Through the coupling of E - GTP and G - GTP, which is another instance of GTP for modeling geological bodies, the integral real - 3D spatial modeling for engineering and geology is possible. The subsurface spatial objects are abstracted into point - entity, line - entity, face - entity and body - entity, and are represented by six geometrical primitives including node, TIN - edge, side - edge, TIN - face, side - face and GTP components. This paper emphasizes on the modeling principal and method of E - GTP, and the integral object - oriented data structures of the six primitives are also introduced.