Study On Deformation And Failure Regularity And Anchorage Technology In Large Section Coal Roadway

China is a big country of coal reserves, and coal production country. With the urgent demand of the development of coal production, the solution of the problem of mine ventilation and the use of large-scale modern comprehensive mechanical equipment continues to increase, the more and more coal mine use large section roadway. At present, the width of many large-scale mine roadway has reached5-6m, sectional area has reached15-20m2, the span of open-off cut has exceeded10m, sectional area up to40m2, and some are even greater. Enlargement of roadway cross-section brought many unpredictable problems what can not be ignored for the roadway support. The common problems such as: large deformation of surrounding rock, roof, two side to collapse, anchor stress increases, and even pulled off, cut. The root causes of these troublesome problems recurring is physical, mechanical properties of coal roadway surrounding rock have no correct understanding, mine pressure of large section roadway characteristic hasn’t really grasped, large section roadway instability and surrounding rock and supporting interaction mechanism have not thoroughly been revealed.Arounding the stability of the large section roadway control, taking Shanxi coal transportation and marketing group Yangcheng Xihe Coal Co., NO.1mining area transportation roadway as engineering background, on the basis of the existing control of surrounding rock, support theory and technology research, this article systematically from five aspects of the mechanical characteristics of large section roadway, the different sections of the mine pressure manifestation, the rheology of rock and the bulking deformation, large section coal seam roadway failure mechanism, anchoring mechanism of large section roadway to summarize a more complete and thorough in large section coal roadway surrounding rock degeneration law. In a word, the main work of this paper and some useful conclusions obtained as follows:(1) Take circular and rectangular roadway as model to research mine pressure behavior after roadway section increased. Increasing of roadway section will not cause changes in mine pressure obviously, distribution of the stress are basically the same, plastic zone and roadway surface displacement increase somewhat.(2) Build15different size roadway numerical model, generally grasp mine pressure behavior law,such as, the stress distribution of surrounding rock, deformation, plastic zone service, rock separation, damage range of strata.(3) It is pointed out that the determination method in existence of large section coal roadway without consider the two important aspects of the effect of roadway stability-rock major omission and rock strength. According to the relationship of the supporting structure of the ultimate bearing capacity and the deformation of surrouriding" rock pressure is a pair of "contradiction",’puf forward a view that in the same geological conditions, definition of large section coal roadway should correspond with a particular supporting, in other words, in the precondition that the supporting pattern and the premise of stiffness, density, strength are determined, it is large section coal roadway size when roadway supporting is completely failure.(4) Lateral creep displacement of rock mass is always the main harmful deformation of roadway, but also support to control the deformation. Put forward the part of the surrounding rock creep deformation. It is difficult to control coal roadway surrounding rock (especially for a two) creep deformation that coal rock is easy to rheological and difficult to stop being accelerated creep from the stress.(5) By the graphic method, reveals the objective fact of rock sliding, overturning after rock mass failure, and at the same time accompanied by broken rock mass inside the hollow and the volume expansion. In addition, detailed state broken rock periodically stable-instability-stable cycle process, in the meantime, the overall volume continues to increase, bearing capacity of the rock mass structure fluctuate reduce, rock continuous crushing smaller.(6) Summarize failure characteristics, types, influence factors of the large section roadway surrounding rock. From two aspects of surrounding rock unloading failure and roadway roof beam structure stability, analysis failure mechanism of coal roadway with large section (7)Based on mine pressure behavior feature of large section coal roadway, put forward seven supporting principle. Give a new state of compression reinforcement theory, Suspension theory, reducing span theory and other classical anchoring theory in large section coal roadway. From three aspects: support strength provided by the anchor, the discontinuous surface reinforcement, constraints on rock fragmentation, discuss on anchorage mechanism of large section roadway(8) Through Xihe Coal Co., NO.1mining area transportation roadway anchor parameters design, supporting scheme determine and field coal pressure observation, observation data show that anchorage support scheme of determined by this paper can effectively control the deformation of surrounding rock. Anchor supporting control surrounding rock deformation within an acceptable range, the anchoring structure force is moderate.Roof peep image display roof lithology condition is good, does not appear large range damage loosening.There are45figures,7tables and73referrnces.