| Through rock creep experiment, theoretical analysis, numerical simulation and field observation, the influence characteristics of rock rheology on gob-side entry retaining of Jiaoxue coal mine was studied, and the Ⅲ shape and parameters of roadway support in gob-side entry was analysed.(1) Based on uniaxial creep experiment, the rheological characteristics of roof and floor rocks of 15031 working face was described by Burgers rheology model.(2) Based on rheological theory, the viscoelastic deformation and stress of the main roof was calculated.(3) Through mechanical analysis, the rise-span ratio of circular beam was optimized.(4) The influence of rheology on the deformation of surrounding rocks in gob-side entry retaining was simulated through FLAC3 D. When the working face advanced slowly, the deformation speed of surrounding rock decreased, however, the total deformation increased due to rheological behavior. So, increasing the advancing speed can reduce the rheology time, which is beneficial to control the roadway deformation.(5) The observation shows that the deformation process was divided into three periods: ‘rapid deformation’, ‘slow deformation’, ‘basic stability’, which were behind working face 0~35m, 35~120m, >103m respectively.The conclusions are beneficial to improving the control effects of gob-side entry retaining surrounding rocks, and provide theoretical basis for the application of gob-side entry retaining. |
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