基于圆柱体轴向包围盒检测的巷道相交建模

针对岩土工程中三维巷道相交建模复杂、运算时间长的问题,根据巷道的几何特性,提出了一种圆柱体-轴向包围盒的双层包围盒检测方法。该方法能够快速查找出可能相交的三角形单元,结合三维实体布尔运算实现了一种不规则三角形网(TIN)巷道曲面相交的快速构建方法。详细讲述了圆柱体-轴向包围盒(AABB)双层包围盒碰撞检测的基本原理以及实体相交布尔运算中的关键技术,对生成的实体网格提出优化方案。通过工程实例验证,在巷道曲面相交建模中,相比于层次有向包围盒(OBB)算法,圆柱体-AABB双层包围盒在包围盒生成方面效率提高近50%,具有建模简单、检测时间短、顶层检测准确度高等特点。

Tunnel intersection modeling based on cylinder-axis aligned bounding box detection

Aiming at the problems of too long operation time and complex modeling of the three-dimensional roadway intersection modeling in geotechnical engineering, a method about cylinder-Axis Aligned Bounding Box (AABB) two-level bounding box detection was proposed according to the characteristics of tunnel's shape. The proposed method could quickly find out the possible intersected triangular elements and established a new approach to solve the Irregular Triangular Network (TIN) modeling problem of tunnel intersection by combining the three-Dimensional (3D) Boolean operation. The basic principles of the cylinder-AABB double bounding box collision detection and the key technologies about Boolean operation to implement intersection modeling in 3D were described, and an optimization scheme for generated entity mesh was proposed. Through the engineering examples, it is proved that, compared with the Oriented Bounding Box (OBB) hierarchical bounding box method, the modeling method by cylinder-AABB detection increases nearly 50% on the bounding box production efficiency in the roadway surface intersection modeling. The proposed method has the advantages of simple modeling, short detection time, high top detection accuracy, and so on.