关键词: 锚杆, 腐蚀, 协同作用, 矿物质

Abstract: The instability of the surrounding rock caused by the failure of anchoring material showed diversity， in which the failure of anchoring material caused by the corrosion at the mine multi-attribute corrosion environment was more and more serious. Rock bolts corrosion cracking occurred frequently in clay-rich areas， which indicated that the synergic influence of mine multi-attribute environments (oxygen content， groundwater and minerals) are the influencing factors. In order to study the law of corrosion under the synergic influence of the mine multi-attribute environments， the rock bolts service environment was simulated in laboratory with the application of “corrosive cell”. The study results showed that the presence of clay indirectly affected the corrosion of rock bolts by increasing the ion concentrations in aqueous solution through the ions exchanges of the minerals. Corrosion is a long-term process， after three months of testing， most of the corrosion products were formed at the end of screw and bolt as well as the part wrapped by clay and coal. The observations indicated that minerals could accelerate the corrosion of rock bolts. Compared with the tensile strength of bolt specimen corroded only by deionized water， the tensile strength of rock bolt specimen corroded by clay or coal decreased. The tensile strength of bolt was the smallest when coal and clay are used as corrosion medium， which indirectly shows that mineral materials can accelerate the corrosion of rock bolt. The study results further show that coal， clay and groundwater in the environment increased the corrosivity of the environment by increasing the total ion concentration of the solution. Therefore， in the area containing minerals and groundwater， the design and maintenance of the support system should be considered in terms of anti- corrosion.

Key words: Rock bolts, Corrosion, Synergic action, Minerals