关键词: 冻融循环, 化学腐蚀, 岩石损伤, 蠕变特性, 试验研究

Abstract: To study the combined influence of chemical corrosion and the freeze-thaw on the damage and creep characteristics of rock, the quartzite and quartz sandstone of Dadongshan tunnel are adopted to be the test specimens. After being soaked in different chemical solutions and subjected to freeze-thaw cycles with different cycle times, the rock specimens are scanned by the electron microscope to analyze themicroscopic characteristics of rock surface. The triaxial creep tests are carried out to analyze the combined influence of chemical corrosion and freeze-thaw on the parameters of instantaneous strain, creep strain, creep rate and long-term strength of rock. The results show that the rock is damaged under combined influence of chemical corrosion and freeze-thaw cycle, the degree of damage increases with the increase of freeze-thaw cycle time, and the influence of chemical solutions increases by the following orders, HCl solution, NaOH solution and NaCl solution. The creep mechanical parameters of rocks change obviously with the change of freeze-thaw times and solution environment. With the intensification of chemical corrosion and the freeze-thaw cycle, the fracture morphology of rock has a tendency to change from brittleness to ductility. It can be indicated that, in the damage process of rock specimens, the freeze-thaw cycle and chemical corrosion promote each other mutually, since the combined influence of two-factor on rock damage and creep characteristics are greater than the influence of single factor.

Key words: freeze-thaw cycle, chemical corrosion, rock damage, creep property, experimental research