An integrated automated parameter optimization method based on FDEM and Isight for rock mass engineering: A case study of pillar stability design

Authors

• ZHU Defu, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, ChinaFollow
• GAO Bolong, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, ChinaFollow
• XU Jiabo, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
• WANG Deyu, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
• GAO Peng, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
• LI Yalin, Norman B. Keevil Institute of Mining Engineering, The University of British Columbia, Vancouver, British Columbia BC V6T 1Z4, Canada
• HU Wenshuo, Key Laboratory of In-situ Property-improving Mining of Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China

Abstract

Background Conventional rock mass engineering design largely relies on empirical equations or numerical simulation schemes selected from a limited number of comparable cases, making it difficult to effectively balance multiple constraints such as safety, economic viability, and resource recovery. The finite-discrete element method (FDEM) based on the intrinsic cohesive zone model (ICZM) can effectively simulate the evolution of quasi-brittle materials from continuous to discontinuous behavior, rendering it particularly suitable for engineering issues involving highly discontinuous rock masses. Therefore, FDEM has become an important numerical analysis method in rock mass engineering. However, there remains an urgent need for a high-precision, integrated, and automated parameter optimization method that combines rock mass engineering design with the FDEM simulation. Methods To address the technical challenge of selectively inserting zero-thickness cohesive elements along complex geometry interfaces in the Abaqus software, an open-source plugin termed ACE was developed using the Abaqus Python API. The plugin enables the global and local selective insertion of zero-thickness cohesive elements along any specified mesh edges. Accordingly, an Abaqus-FDEM numerical simulation framework incorporating the ICZM was established. To enhance the automatic degree of parameter optimization in rock mass engineering, a multi-platform-integrated FDEM-based parameter optimization method allowing for whole-process automation was proposed. Using the Isight optimization platform, the proposed method integrated multiple modules, including parametric modeling through Rhino-Grasshopper, adaptive meshing using Gmsh, and numerical simulation and automated result extraction using Abaqus. Driven by Python scripts, an integrated, automated optimization workflow was established, covering geometric modeling, mesh generation, cohesive element insertion, FDEM numerical simulation, and macroscopic response extraction. Results Against the engineering background of a certain room-and-pillar stope, single-objective automated optimization was performed using the Nelder-Mead optimization algorithm under a fixed goaf span of 5 m, with the pillar width defined as the sole design variable. The purpose was to determine the minimum pillar width while satisfying the bearing capacity requirements of pillars. The results indicate that under a goaf span of 5 m, the minimum pillar width ensuring adequate bearing capacity was 3.5 m. Conclusions The fully automated parameter optimization method proposed in this study demonstrates strong reliability. As the primary achievement of this study, an open-source, free, and easily accessible tool for inserting cohesive elements is developed based on the Abaqus platform and the FDEM method. Furthermore, the results of this study provide a novel idea for parameter simulation and optimization in rock mass engineering.

Keywords

rock mass engineering, optimization method, cohesive element, finite-discrete element method (FDEM), pillar size, parameter optimization, Isight

DOI

10.12363/issn.1001-1986.26.02.0075

Recommended Citation

ZHU Defu, GAO Bolong, XU Jiabo, et al. (2026) "An integrated automated parameter optimization method based on FDEM and Isight for rock mass engineering: A case study of pillar stability design," Coal Geology & Exploration: Vol. 54: Iss. 8, Article 18.
DOI: 10.12363/issn.1001-1986.26.02.0075
Available at: https://cge.researchcommons.org/journal/vol54/iss8/18

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