金川深部工程围岩支护时机与参数设计研究

Study on Time and Parameter Design for Engineering Support of Wall Rock at Depth in Jinchuan Mine

为了解决复杂地质环境下的围岩支护时机问题,针对金川三矿1165水平一大跨度硐室围岩进行了一系列理论和数值分析研究。首先,根据现场调查,对围岩进行了初步的工程地质评价,认为该岩体处于不稳定状态;然后,针对金川岩体的流变特征进行了理论研究,建立了非线性流变模型,通过拟合得出了最佳二次支护时机;最后,根据岩体变形特点,提出"适当让压后支护"思想,采用数值计算方法对硐室支护进行了设计研究,并得出了一系列结论。该研究表明适当让压后进行支护有利于提高围岩体的自承能力,有利于工程的长期稳定性。

In order to solve the problem concerning the wall rock support time in complex geological environment, a series of theoretical and numerical analysis were made on a large span cavity at 1165m level in Jinchun No. 3 Mine, First, based on site survey, preliminary engineering geological evaluation on the wall rock was made and it was concluded that the wall＂ rock was in unstable status. Then, theoretical study was carried out on the rheology of Jinchuan rock mass and a nonlinear rheological model was established. The best secondary support time was found by fitting. Finally, in light of the rock mass deformation characteristics, a concept of ＂support after proper stress release＂ was proposed, and study was mad on cavity support by numerical calculation method, resulting in a series of conclusions. The research results indicate that support after proper stress release will facilitate the improvement of the self-carrying capability of wall rock mass and consequently, the long term stability of the support engineering.