Meso-structure based numerical simulations of deformation and failure of granite.. Thermal-mechanical coupling
Abstract：Scanning electron microscopy (SEM) was used to obtain non-homogeneous digital images of rocks. The corresponding element mass centroid method has been presented to estab- lish three-dimensional finite element model of rock based on SEM images in this paper. This method considers existing defects and approximates a truly non-homogeneous micro-structure characteristic of geo materials. Simulation of thermal-mechanical coupling on thermal cracking and failure in Beishan granite has been done. Thermal cracking in the granite is theoretically estimated to occur at 82 ~C, in good agreement with our recent experimental estimate of 68 to 88 ~C. Inter-granular thermal cracking is the main cracking mechanism at low temperatures. In this case cracks propagate along mineral grain boundaries. At high temperatures the cracking mechanism is a trans-granular coupled with an inter-granular mechanism. Deformation changes from brittle, at low temperatures, to ductile at high temperatures. Crack distributions at final failure change from that typical of low temperature, a load failure, to those typical of high tem- perature, namely thermal failure. Numerical predictions are higher than the experimental load at failure when working at low temperatures. However, the numerical predictions and experi- mental results are in good agreement at higher temperatures.
Keywords：element mass centroid corresponding methodthermal-mechanical coupling effectsBeishan granitemeso-structurenumerical simulation
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：8( 878-884,922 )