The Research of the Arbitrary Excavating Algorithm for the Stratum Structure Model

According the research of the arbitrary excavation method for the three dimensional geologic stratum model, we can be used to analyze the inner structure feature effectively in the geological work. This algorithm is based on the three dimensional geological objects represented by TIN structure. And it extracts the two key operating: ldquothe generation of the cross sectionrdquo and ldquothe partition of geological bodies which is being cutrdquo after the geologic stratum model being cut, and realizes the propose of purpose of the closure and segmentation. Compared with the classical, algorithm, this algorithm brings some obvious improvements. It converts the complex cutting problems to a serial of simple operations: collision detection, intersection between a line segment and a triangle, triangle mesh reconstruction, the position test between point and curve, surface or polyhedron, etc. And it expounds the excavating algorithm for the stratum model cut by the arbitrary geometric body. By cutting test with some underground geological model of Guangzhou China build with borehole data and crossing section map data, the algorithm successfully solves the problem of three dimensional geological models analysis such as arbitrary cutting, generating fence diagram, foundation ditch digging, pit excavation, tunnel digging and virtual drilling by means of three-dimensional method.