Fracture evolution of overlying strata over combustion cavity under thermal- mechanical interaction during underground coal gasification
Abstract：The thermo-physical properties and uniaxial compression experiments of mudstone and sandstone under high temperature were conducted to obtain the basic physical and mechanical parameters at varying temperatures. The gov- erning equations of thermal-mechanical coupling incorporating the evolution of rock damage were established based on the thermodynamics and elastic mechanics. With the background of an underground coal gasification field, the combus- tion cavity growth under the thermal-mechanical interaction was modeled and the characteristics of temperature and fracture distribution of overlying strata were analyzed. Finally, the bore hole survey method was employed to test the height of fractured zones of overlying strata. The field test results agree with the numerical simulation results, which verify the rationality of the numerical model.
Keywords：underground coal gasificationthermal-mechanical couplingcombustion cavityoverlying stratatempera- ture fieldfracture field
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 1292-1298 )