Impact Study And Control Scheme Of Seam Mining Under Mined-Out Area In High Speed Highway

Along with the great development of western China, coal gob areas are becomingthe barriers to development of highway in western provinces, and theexisting norms cannot fully meet the needs of highway construction under thiscomplicated coal gob geological conditions. Meanwhile, it is difficult to judge what’sgood and bad for multiple-choice governance schemes objectively and scientifically.Therefore, it needs to research on the characteristic of coal gob areas, and systematicallyanalyze the influence factor of ground stability for coal gob areas, and then we cangeneralize respective effect mechanisms so as to provide reference to select the bestscheme for highway construction.Based on plenty of investigations and practical engineering experiences, this papermakes a deepened discussion about the features of surface deformation and moving forcoal gob areas, and researches interaction characteristics between roadbed of highwayand coal gob areas under the highway, and thus develops a new method of subgradestability evaluation when highway passing through the coal gob areas, which is appliedto the engineering instance resulting in the best governance scheme.The main contents of this paper are as follows:Firstly, with the step-by-step analysis of the features of surface deformation andmoving for coal gob areas, this paper studies its reason produced, summarizes variousfactors, such as coal mining, dip angle of coal seam, the ratio of depth and thicknessfor coal mining and topographic and geologic conditions which affect the deformationof surface deformation and moving for coal gob areas.Secondly, based on the research of interaction characteristics between roadbed ofhighway and coal gob areas under the highway, the influence mechanism of surfacedeformation and moving for coal gob areas to highway subgrade is put forward. And wecan get the distribution characteristics of subgrade reaction, according which theinfluence of the additional load of highway to surface stability in coal gob areas.Thirdly, the influence of residual deformations of old coal to the highway isstudied.Fourthly, this paper studies the prediction of surface deformation and moving forcoal gob areas and methods of stability evaluation. And two level fuzzy comprehensivehighway evaluation method of surface stability for coal gob areas is put forward based on interaction characteristics between roadbed of highway and coal gob areas under thehighway.Fifthly, combining with the engineering of Nanwan Highway in Chongqing, thefeasibility of new method of stability evaluation will be tested by practical, and at thesame time, the design plan of highway subgrade and pavement structure which are fit.