Under Into The Side Of The Road To Help The Stability And Design Optimization Of Route Layout

With the increasing excavation depth and the truth of several-level mining, the stability of underhand cut-and-fill drift stoping is always the difficult problem faced by metal mine. As an important method for difficult-to-mine orebody, the underhand cut-and-fill drift stoping has been applied widely. It is necessary to study on engineering geology and rock mechanics problems of underhand cut-and-fill drift. This study has important theoretical and practical significance.This paper relies on the national key technology R&D program in the 11th five year plan of china"Study on the highly effective key technology and furnishment for difficult-to-mine metal orebody". Field geologic surveys and plenty data in existence have been analyzed in detail, a research on the underhand cut-and-fill drift of the northern part of Wushan copper mine is started from geologic setting and the characteristics of the engineering. Then the crustal stress of mining area, the rock mechanics characteristics of the backfill body and surrounding rock mass of underhand cut-and-fill drift, the structures of rock mass, the mechanism of interact of backfill body and surrounding rockmass, the stability of rock mass and so on have been outspreaded in order to evaluate the stability of the stope. Linked with this engineering and some problems or shortages in the study of the stope's stability of underhand cut-and-fill drift, some methods have been put forward to mend and perfect the study on the stope's stability.In the study of this paper, the structure evolution of the mine area was studied depending on the structure analysis method. Based on the data of fault slip and the recent earthquake, the present tectonic stress field and the paleotectonic stress field have been analyzed and compared.The criterions to identify a movable block body, which formed in connect are between the backfill body and underhand cut-and-fill drift was discussed in detail and set up using spatial analytic geometry method. At the same time, a topology relationship between points of intersection, lines of intersection and the plane is discussed, and then a basic method to distinguish the vertexes of block body from those points of intersection is put forward. The parameters such as the areas, volumes, barycenter and so on of the four-faces and the five-face block body are evaluated by the mathematics method. Due to the influence of back-fill body on movable block body, a new method of calculating the stability coefficient of movable block body was put forward by elasticity mechanics method. In order to search the block bodies which maybe occurred between the backfill body and the surrounding rockmass of underhand cut-and-fill drift, a method was put forward using the random process theory and block body theory, and a program is compiled.The influence of the maximum horizontal principal stress on movable block body was discussed by using spatial analytic geometry method and mechanic method, and a method of study the influence on the stability of underhand cut-and-fill drift from crustal stress was put forward. Using fuzzy approach degree, a method of evaluates the stability of different stope and different direction underhand cut-and-fill drift was put forward.In the study of the mechanism of interact of backfill body and surrounding rockmass , 2-D"RFPA"finite element analysis technique is used to simulate the stress field and deform field which is induced by different shape cross-section. The influence law of instability part was obtained by simulating the acoustic emission key point during excavation by steps.Based on those studies above, and according to the results from synthesis analyzing the main control actors of the stability of underhand cut-and-fill drift, a method of layout and mining sequence of underhand drift was put forward, and the material scheme of intersecting the drifts between the upper slice and the lower slice was put forward.