Geomechanical Simulations Related to UCG Activities
This paper presents results from a recent investigation into a range of geomechanical processes induced by UCG activities. The mechanical response of the coal and host rock mass plays a role in every stage of UCG operations. For example, cavity collapse during the burn has significant effect upon the rate of the burn itself. In the vicinity of the cavity, collapse and fracturing may result in enhanced hydraulic conductivity of the rock matrix above the burn chamber. Even far from the cavity, stresses due to subsidence may be sufficient to induce new fractures linking previously isolated aquifers. These mechanical processes are very important in understanding the risk of unacceptable subsidence and the potential for groundwater contamination. The mechanical processes are inherently non-linear, involving significant inelastic response, especially in the region closest to the cavity. in addition, the response of the rock mass involves both continuum and discrete mechanical behavior. To better understand these effects, they have applied a suite of highly non-linear computational tools in both two and three dimensions to a series of UCG scenarios. The calculations include combinations of continuum and discrete mechanical responses by employing fully coupled finite element and discrete element capabilities.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 953295
- Report Number(s):
- LLNL-CONF-405392; TRN: US200915%%165
- Resource Relation:
- Conference: Presented at: Geomechanical Simulations Related to UCG Activities, Pittsburgh, PA, United States, Sep 29 - Oct 02, 2008
- Country of Publication:
- United States
- Language:
- English
Similar Records
Progress on a New Integrated 3-D UCG Simulator and its Initial Application
Geomechanics-Based Stochastic Analysis of Injection- Induced Seismicity