裂纹扩展过程红外热像实验及数值模拟研究

摘要

An experimental research of the infrared thermal image in the process of rock fracture was carried out.The study used the granite with the double crack objection analyze the crack initiation,propagation,coalescence,interaction,and the change of macro-strength leaded by them.I did the infrared thermal image examination and numerical simulation for 7 granite sample with double crack to view the regularity of rock failure.The results evince that the AE prognostic of rock＇s brittleness fracture is not obviously.There will be small scale AE phenomenon before the rock＇s main fracture,and they release a little energy.When the rock happens the main failure,it will bring out lots of AE,especially in rock burst.The event of experiment confirmed that there are infrared abnormal phenomenon during the rock facture process,and the high temperature realm or stripe at the fracture field.The experiment results indicated that the infrared characteristic of porphyritic texture granite before failure represents the high temperature prognostic.%采用花岗岩材料通过红外热像和数值实验的方法,对两预制裂纹导致的岩石中新裂纹孕育、繁衍、萌生、扩展和贯通机制,以及由此引起的试样宏观强度变化等进行分析.通过红外热像遥感观测方法以及数值模拟对7块预制双裂纹的试样进行了实验研究.结果表明,裂纹扩展过程中,脆性破裂的声发射前兆不明显,在主破裂发生之前有小规模声发射现象,但释放的能量不多,只有在主破裂发生时产生大量声发射,特别是岩爆类型的破坏.试样破裂过程中有红外异常现象,在破裂处会出现明显的高温区和高温条带,并指出斑状花岗岩在破裂前主要表现为高温前兆.