The Deformation Failure Mechanism And Supporting Research Of The Water-rich Soft Rock Roadway

In the construction and production process of the coal mine, the deformation control of the soft rock roadway has always been a problem, especially when the roadway is in the water-rich poor state address, the deformation and stability mechanism of the water-rich soft rock roadway is much more complex than the average roadway. The large deformation of the water-rich soft rock roadway does not only increase the cost of roadway repair, but also brings the great safety hidden trouble. In this paper, we take the water-rich soft rock roadway in the Ⅳ1 pump room of Yuanzhuang Coal Mine as the research object. Through on-site survey, laboratory test, and in-situ test, we deeply analyze the deformation failure mechanism and stability control principle of the water-rich soft rock roadway to get an efficient and convenient supporting method, providing conditions for the mine safety production.This paper based on analysising the deformation failure reason of the Ⅳpump room water-rich soft rock roadway shows that the main mechanism of deformation and failure:after the roadway is excavated, the stress state of the surrounding rock mass is broken forming a surrounding rock loose circle around the roadway which is very unstable; the phenomenon of softening and argillitization happens when the surrounding rock is in water immersion state, so the compressive strength of the rock is only 8% of dry compressive strength losing bearing capacity; the stability of the roadway is further weaken under the "Water-rock interaction"; the unstable rheological properties of the rock which is in water immersion state accelerates. According to the analysis of the deformation failure mechanism, we dig deeper into the essence of the control deformation mechanics principle. Based on the mechanisms, we obtaine "the Anchor Mesh strong shell Supporting Principle applying laneway’s side" and "the anchor rope (rod) arch bearing weaken system applying the roof-floor-laneway’s side", and we deeply analyze the loose circle of grouting reinforcement mechanism. Based on the above principle, this paper proposes an efficient composite support method which is applied into supporting roadway in water immersion state, namely the "double steel fabric shotcrete layer+grouting anchor rope(rod) composite support". Modeling of numerical simulation software ABAQUS is used to calculate the feasibility of the supporting schemes. At the same time through the field industrial test, we demonstrate that the support scheme achieve good effect in support of the water-rich soft rock roadway. From what has been discussed above, The results of this paper provides valuable experience to the similar roadway support.