Meter-scale Experimental And Numerical Study Of The Thermal-Hydrological-Mechanical Coupling In Fractured Rocks

This paper based on the background of the research status for the deep geological disposal project of high level radioactive waste (HLW), research its thermal-hydrological-mechanical (THM) multi-field coupling by indoor meter scale model test and numerical simulation. The major contents and research achievements are as follow:(1) In the background of the China’s first proposed high-level radioactive waste underground repository project, under the guidance of the theory and existing research, develop thermal-hydrological-mechanical multi-field coupling model test program and the corresponding test preparatory work, Including program development、test components、test modeling and debugging. Use32granite test block that collected in Gansu South Mountain to constitute a model of the fractured rock mass. Conduct thermal-hydrological-mechanical (THM) multi-field coupling model test under the conditions of heat on the right side, force on the left side, vertical seepage and surrounding insulation(2) Use the experimental device to test thermal-hydrological-mechanical coupling in fractured rocks. First step, conduct a single field tests of the hydrological field. Second, conduct thermal-hydrological field coupling model test. Last, conduct the thermal-hydrological-mechanical (THM) multi-field coupling model test. An analysis of the variation of three fields and their mutual influence, focus on the impact that mechanic field on thermal and hydrological field.(3) According to the results of model test, use finite difference numerical analysis software FLAC to simulate the model test. On this basis, study three coupling effect of fractured rock mass in numerical simulation. Observe the impact that mechanic field on thermal and hydrological field in numerical simulation.(4) Compare the results of numerical simulation and model test, shows that they coincide a lot, but also have some differences, specifically manifested in the impact that mechanic field on thermal and hydrological field. This phenomenon is more obvious in numerical simulation than in the model test. On this basis, study the near-field fractured rock mass characteristics of high level radioactive waste deep geological storage.