It is hot and difficult point that research on thermo-hydro-mechanical (THM) coupling for fractured rock mass at present. Firstly

the research status of mechanism

models

numerical simulation methods and contents for multifield coupling of fractured rock mass are summarized. Meanwhile

the significant effect on THM coupling of fractures is analyzed. As a result

the critical problem considering the fracture network propagation and its simulation during the THM coupling is proposed. Furthermore

3 critical points are pointed out: (1) building the THM coupling model which can consider the fracture network propagation; (2) selecting numerical simulation method of simulating fracture propagation; (3) proposing the simulation algorithm for THM coupling and the whole process of rock mass from deformation to collapse. Then

the numerical methods for simulating coupling and fracture propagation are classified and compared; therefore

the various numerical methods

including finite element method

element-free method

partition of unity method

discrete element method

rock fracture process analysis method and numerical manifold method

are discussed thoroughly and particularly

from the advantages and disadvantages. Following

the numerical manifold method (NMM) is recommended for solving the critical problem. Finally

some ways and difficulties of the work are discussed preliminarily.