Application of a vertex chain operation algorithm on topological analysis of three-dimensional fractured rock masses

Abstract

Identifying the morphology of rock blocks is vital to accurate modelling of rock mass structures. This paper applies the concepts of directed edges and vertex chain operations which are typical for block tracing approach to block assembling approach to construct the structure of three-dimensional fractured rock masses. Polygon subtraction and union algorithms that rely merely on vertex chain operation are proposed, which allow a fast and convenient construction of complex faces/loops. Apart from its robustness in dealing with finite discontinuities and complex geometries, the advantages of the current methodology in tackling some challenging issues associated with the morphological analysis of rock blocks are addressed. In particular, the identification of complex blocks with interior voids such as cavity, pit and torus can be readily achieved based on the number and the type of loops. The improved morphology visualization approach can benefit the pre-processing stage when analyzing the stability of rock masses subject to various engineering impacts using the block theory and the discrete element method.

Keywords

morphology / block assembling / vertex operation / discontinuities

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Acknowledgement

The research was conducted with funding provided by the National Basic Research Program of China (973 program, No.2014CB046905), the National Science Foundation of China (Grant No. 41672262), the State Key Laboratory for Geo mechanics and Deep Underground Engineering (No.SKLGDUEK1303), and the Department of Communications of Guangdong Province (No.2016).

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