Theoretical and numerical study on the cryogenic fracturing in rock
TANG Shibin1，2，LUO Jiang1，2，TANG Chun?an1，2
(1. School of Civil Engineering，Dalian University of Technology，Dalian，Liaoning 116024，China；
2. Institute of Rock Instability and Seismicity Research，Dalian University of Technology，Dalian，Liaoning 116024，China)
Abstract：Thermal cracking of rock induced by cryogenic liquid is widely observed in oil and gas exploitation，geothermal development and liquefied petroleum gas storage etc. To study the cryogenic fracturing，a theoretical solution of the temperature and stress distribution in a plate was derived with the thermo-elastic theory. The heat conduction characteristics and associated thermal stress evolution in the plate was theoretically studied with the derived theoretical formula. The effects of heat transfer coefficient on cooling rate and increasing rate of tensile stress were also analyzed. The results show that when the rock surface contacts with cold liquid，the temperature on the contact surface decreases rapidly at first，then slowly and finally the same as the environment temperature. The tensile stress rises sharply firstly and then decreases，and finally decreases to zero. In addition，the crack initiation，propagation process of cryogenic fracture in rock under thermal shock are numerically simulated. The effect of the heat convection coefficient on the evolution of temperature，stress distribution，the fracture mode and the number of fractures were analyzed. The numerical results indicate that increasing the heat convection coefficient not only raises the tensile stress on the contact surface between liquid and solid which results in rock easier to crack，but also raise the number of cracks which are helpful for enhancing the permeability of low permeability reservoirs.
唐世斌1，2，罗 江1，2，唐春安1，2. 低温诱发岩石破裂的理论与数值模拟研究[J]. 岩石力学与工程学报, 2018, 37(7): 1596-1607.
TANG Shibin1，2，LUO Jiang1，2，TANG Chun?an1，2. Theoretical and numerical study on the cryogenic fracturing in rock. , 2018, 37(7): 1596-1607.
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2018, Vol. 37 
