Studying on Support Technology of Broken Seam Roadway with High Stress and Large Section
|School||Shandong University of Science and Technology|
|Keywords||high stress large section fractured surrounding rock seam roadway UDEC lag grouting parameters optimization|
With the development of full-mechanized mining technology with high production and high efficiency of modern mine, mining intensity and scale of mine increased greatly, mine mining gradually developing in depth, the geological conditions becoming more and more complicated and the in-situ stress increasingly high, all the above cause the phenomena of big construction difficulties, supporting structure deformation and cracking, short service life and highly repair rate universal existence. Meanwhile, in order to meet the need of ventilation, coal transportation, equipment installation and so on, roadway section also becomes larger and larger. The support difficulties significantly increased with deep burial and big section of the tunnel. Large section roadway supporting questions especially prominent, in the condition of it’s surrounding rocks weak and friable, which brings great trouble to the maintenance of roadway and seriously affected the safety and high effective product of coal mines. The supporting technology of broken seam roadway with high stress and large section has become an imperative problem to be solved.The paper uses the support questions of beiqu belt conveyer transportation tunnel of Longgu Mine as its background. On the basis of fully understand of its engineering characteristics, the paper firstly studied the surroundings’deformation and failure mechanism of broken seam roadway with high stress and large section, detailed analysis are made to describe the distortion and failure features, influence factors and failure mechanism of broken seam roadway, moreover, a deep analysis was made for the surroundings’deformation mechanism from the mechanical point of view. On the basis of detailed analysis of roadway supporting ideas and the selection of supporting form, the paper puts forward a supporting principle of broken seam roadway with high stress and large section. Also, the of reinforcing sides and roof grouting support technology, mainly reinforce the roof, two sides and bottom angle, was proposed according to the practical project. The supporting effect of bolt-net-cable-belt-shotcrete-grouting combined support was simulated and analyzed by UDEC distinct element analysis software, which closely connect with theory analysis and actual project, further verified the reasonability of lag grouting reinforcement technology. Finally, the grouting parameters were determined through the analysis of lag grouting reinforcement characteristics, and the method of numerical simulation was used to optimize the parameters of anchor space, anchor length, grouting pressure and grouting depth.Through the above analysis and research, the paper established a more complete theoretical system and support measures, which has higher reference and application value for similar engineering.