Disclosure of Invention
In order to solve the problems of roadway maintenance and coal pillar region stress concentration in the coal pillar-free mining, realize the coal pillar-free mining, reduce the loss of coal pillars in sections, reduce the tunneling rate and the construction cost of a roadway and improve the coal recovery rate of a mine, the invention provides a large-section roadway prefabricated wall coal pillar-free mining method based on intelligent mining, and the specific technical scheme is as follows.
A large-section roadway prefabricated wall body coal pillar-free mining method based on intelligent mining comprises the following steps:
A. excavating a stoping roadway, arranging filling walls in sections behind an excavation head in the excavation stage of the stoping roadway, reserving connecting roadways among sections of the filling walls, and enabling the distance between the filling walls and the working surface of the upper section to be smaller than the distance between the filling walls and the working surface of the lower section;
B. stoping the working face of the upper section, sequentially plugging the connecting roadways between the sections completed in front of the stoping working face of the upper section along with the stoping of the working face of the upper section, and simultaneously performing pre-splitting joint cutting in front of the stoping working face of the upper section;
C. stoping the working face of the lower section, completing stoping of the working face of the upper section and plugging of the connecting roadway, completing tunneling of the stoping roadway of the lower section, completing preparation of the working face of the lower section, and performing stoping of the working face of the lower section;
and (5) repeatedly performing excavation of the stoping roadway and stoping on the working face to finish the pillar-free mining of the mining area.
Preferably, the filled roadway space between the wall and the lower block face serves the upper block face and the lower block face for the full period.
Preferably, the width of the connecting roadway and the length of the filling wall body section are determined according to the height of the mining roadway, the supporting condition of the mining roadway, the thickness of the coal seam and the pressure step distance of the working face.
It is further preferred that the distance of the pre-splitting cut in front of the working face of the upper section is determined by the direct roof thickness, roof lithology and cyclic pressure.
It is further preferred that the bottom of the filling wall body is fixed with the roadway bottom plate, and the top of the filling wall body is fixed with the roadway top plate.
Preferably, the pre-splitting joint-cutting inclination angle in front of the upper-section stoping working face is specifically that the top plate of the upper-section working face is slotted along the upper edge of the filling wall body, and the slotted angle is larger than 60 degrees; the depth of the pre-splitting joint seam in front of the stope face of the upper section is from a stope roadway to a basic roof.
Preferably, the mining roadway driving, the wall body filling construction, the upper section working face mining, the pre-splitting joint cutting, the connection roadway blocking and the lower section working face mining construction in the steps A to C are automatically controlled, and the steps A to C are applied to intelligent mine mining.
A pillar-free mining method for a pre-built filling wall in a large-section roadway close to a coal seam is characterized in that mining of an upper coal seam is carried out and then mining of a lower coal seam is carried out by the intelligent mining-based pillar-free mining method for the pre-built wall in the large-section roadway.
It is still further preferred that the infilled wall is constructed using a paste infill, a gangue infill or a masonry wall.
Still further preferably, the pillar-free mining method using a pre-built filling wall in a large-section roadway is used in gas mine, rock burst dangerous mine or coal seam group mining.
The intelligent mining-based large-section roadway pre-built wall coal pillar-free mining method provided by the invention has the beneficial effects that:
(1) the method for coal pillar-free mining can more effectively develop coal resources, improves the recovery rate, realizes coal pillar-free mining by pre-building a filling wall body in a large-section roadway, does not need to arrange sectional coal pillars any more, greatly saves the coal resources and prolongs the service life of a mine.
(2) The filling wall body is built in the large-section roadway in a segmented mode, so that part of roadway space can serve the working face of the upper section and the working face of the lower section, the service efficiency of the roadway is improved, the mining succession contradiction is relieved, the mining cost is greatly reduced, and the economic benefit of a mine is improved.
(3) The construction mode of the filling wall body in the method is more flexible, the maintenance of the roadway is facilitated, the stoping roadway is influenced by the mining of the working face, so that the stress on surrounding rocks is larger, larger deformation can be generated, the maintenance of the roadway is difficult, the maintenance amount of the roadway is reduced by pre-building the filling wall body in the roadway, the roadway can be fully utilized by reasonably dividing the width of the roadway on two sides of the filling body, and the deformation amount of the roadway can also be reduced.
(4) The coal pillar-free mining method for pre-building the filling wall body in the large-section roadway is applied to mining of coal beds close to upper and lower layers, so that rock burst disasters caused by coal pillar stress concentration can be avoided, full pressure relief of the coal beds is realized, the air permeability of the coal beds is improved, gas flow of the close coal beds is facilitated under the coal bed group mining condition, and the danger of coal rock dynamic load is reduced.
In addition, the method has important significance for improving the safety of the working face and ensuring high-efficiency mining.
Detailed Description
With reference to fig. 1 to 8, a specific embodiment of the intelligent mining-based large-section roadway prefabricated wall pillar-free mining method provided by the invention is described.
In the description of the present application, it should be noted that the orientations or positional relationships indicated by "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like used in technical terms are based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be configured in a specific orientation, and operate, and thus, cannot be construed as limiting the present application.
Fig. 1 to 3 show the space and position relationship of the excavation of the stoping roadway, specifically including the position relationship between the excavation head 1, the connection roadway 2, the filling wall 3, the stoping roadway 4, the upper section working faces 5, and the lower section working faces 6, wherein the distance between the filling wall 3 and the excavation head 1 is a, the distance is specifically determined according to the actual construction conditions and the roadway conditions, the filling wall 3 lags behind the excavation head construction, the distance between the filling wall 3 and the excavation head 1 needs to be arranged with an excavator, a distance convenient for supporting operation is reserved, and a proper distance for conveying coal rocks is reserved. In addition, the width of the filling wall 3 is B, the width of the connecting roadway is C, the width of the stoping roadway is D, the distance E between the working surface of the lower section and the filling wall is E, the distance F between the working surface of the upper section and the filling wall is F, and the filling wall is arranged in sections along with the advancing of the tunneling head.
Fig. 4 to 7 show the spatial positional relationship in the stoping process of the working faces of the upper section and the lower section, including the positional relationship among the connecting roadway 2, the filling wall 3, the stoping roadway 4, the working face 5 of the upper section, the working face 6 of the lower section, the gob 7 of the working face of the upper section, and the pre-splitting cut 9. And pre-splitting cutting seams are carried out along the filling wall body in the stoping roadway along with the stoping of the working face 5 of the upper section, the angle and the height of the pre-splitting cutting seams 9 can be designed according to the technical conditions of field construction, and the pre-splitting cutting seams 9 are constructed on the advanced section of the working face of the upper section. And (3) along with the stoping of the working face 5 of the upper section, constantly forming a goaf of the working face of the upper section along the pre-splitting joint seam, and along with the stoping of the working face of the upper section, filling a connecting roadway between the wall body sections behind the working face 5 of the upper section for plugging.
A method for mining a large-section roadway pre-built wall without coal pillars based on intelligent mining can more effectively develop coal resources and improve the recovery rate, the large-section roadway is pre-built with a filling wall to realize coal pillar-free mining, and section coal pillars do not need to be arranged, so that the coal resources are greatly saved, and the service life of a mine is prolonged. The method comprises the following specific steps:
A. and (3) excavating a stoping roadway, arranging filling walls in sections behind the excavation head in the excavation stage of the stoping roadway, reserving connecting roadways among the sections of the filling walls, and enabling the distance between the filling walls and the working surface of the upper section to be smaller than the distance between the filling walls and the working surface of the lower section.
And in the tunneling stage, a stoping roadway is positioned between the upper section working face and the lower section working face and is continuously pushed forward along a tunneling head of a mining design, the width of the stoping roadway is D, the end face of the roadway is large, a filling wall body is constructed after the tunneling head, the distance between the lower section working face and the filling wall body is E, and the distance between the upper section working face and the filling wall body is F. The construction of the filling wall lags behind the tunneling head, the distance between the filling wall and the tunneling head is A, the width of the filling wall section is B, and a section of connecting roadway is reserved at intervals of the filling wall, and the width of the connecting roadway is C.
The full-period roadway space between the filled wall and the lower section working surface serves the upper section working surface and the lower section working surface; particularly, the tunnel spaces on two sides of the filling wall body can be used for ventilation, transportation and the like in the process of tunneling and stoping of the upper section, and the tunnel space between the filling wall body and the working surface of the lower section is continuously used for ventilation when the stoping of the upper section is started. The width of the connection roadway and the length of the filling wall body section are specifically determined according to the height of the mining roadway, the supporting condition of the mining roadway, the thickness of the coal bed and the pressure step distance of a working face, wherein the larger the width of the mining roadway is, the larger the width of the connection roadway is, the longer the length of each section of the wall body is, the supporting condition of the mining roadway comprises parameters such as the row distance between anchor rods, and the like, the larger the thickness of the coal bed is, the larger the length of the filling wall body section is, and the smaller the width of the connection roadway is; the length of the infill wall may also be determined based on the step size of the work surface being substantially equal to the length of the infill wall. The bottom of the filling wall body is fixed with the roadway bottom plate, and the top of the filling wall body is fixed with the roadway top plate; the fixing can be realized by arranging groove parts on a top plate and a bottom plate of a roadway and constructing the filling wall body in the groove parts, so that the filling wall body is ensured to be more stable, and the supporting function is better exerted.
The filling wall body is built in the large-section roadway in a segmented mode, so that part of roadway space can serve the working face of the upper section and the working face of the lower section, the service efficiency of the roadway is improved, the mining succession contradiction is relieved, the mining cost is greatly reduced, and the economic benefit of a mine is improved. The construction mode of the filling wall body in the method is more flexible, the maintenance of the roadway is facilitated, the stoping roadway is influenced by the mining of the working face, so that the stress on surrounding rocks is larger, larger deformation can be generated, the maintenance of the roadway is difficult, the maintenance amount of the roadway is reduced by pre-building the filling wall body in the roadway, the roadway can be fully utilized by reasonably dividing the width of the roadway on two sides of the filling body, and the deformation amount of the roadway can also be reduced.
B. And (3) stoping the working face of the upper section, sequentially plugging the connection lanes between the sections completed in front of the stoping working face of the upper section along with the stoping of the working face of the upper section, and simultaneously performing pre-splitting joint cutting in front of the stoping working face of the upper section.
Specifically, after the excavation of the stoping roadway is completed, the stoping of the working face of the upper section is carried out. And in the upper section working face stoping stage, an upper section working face goaf is continuously formed behind the working face along with the propulsion of the upper section working face. And along with the working face of the upper section is stoped, the connection roadway can be plugged at the working face or in a section of connection roadway in front of the working face, so that the connection roadway is plugged on the filling wall body before the goaf of the working face of the upper section is formed, the effect of stopping waste rocks is achieved, the filling wall body is connected into a whole, and the waste rocks in the goaf of the working face of the upper section cannot overflow along the connection roadway. In addition, with the advance of the stope face of the upper section, the continuous pre-splitting cutting seam is carried out along the advance section of the working face of the upper section, and when the working face of the upper section advances forwards in coal mining, the position of the pre-splitting cutting seam is continuously pushed towards the front end along the advancing direction, so that the advance pre-splitting cutting seam and the stope face are always kept at a certain distance.
Wherein the distance of the pre-splitting cutting seam in front of the working surface of the upper section is determined according to the thickness of the immediate roof, the lithology of the roof and the period pressure. The dip angle of the pre-splitting joint seam in front of the stoping working face of the upper section is specifically to cut a seam along the upper edge of the filling wall body to the top plate of the working face of the upper section, wherein the cutting seam angle is more than 60 degrees, and the pre-splitting joint seam inclines from the lateral side of the stoping roadway to the upper side of the working face; the lower edge of the presplitting cutting seam is positioned at the filling wall body, so that a top plate above the roadway can be guaranteed to be timely collapsed, and the bearing above the filling wall body is reduced. In addition, the depth of the pre-splitting joint seam in front of the stope face of the upper section is from the stope roadway to the basic roof.
The direct roof is hard in the upper section working face goaf, so a suspended roof can be formed after the initial collapse, and the hard direct roof can be periodically fractured and collapsed in the propelling process of the upper section working face. The hard roof directly propped against the roof in the range of the stoping roadway is supported by the filling wall, so that a longer hanging roof which is not easy to collapse is formed in the goaf of the working surface of the upper section. The suspended roof can cause certain influence on a filling wall in a stoping roadway, and the specific influence is as follows: firstly, the contact stress between a hard direct roof and an old roof covered on a stoping roadway is obviously reduced along with the appearance of a suspended roof, when the deformation of the roadway is not coordinated, the contact layer surface is easy to generate interlayer slippage, and the shear damage of the contact layer surface can be caused by the condition; secondly, due to the appearance of the overhanging roof, the subsidence of the stoping roadway roof is increased on one side close to the goaf of the working face of the upper section, so that the separation layer between the immediate roof and the old roof is promoted to appear.
The rotary deformation of the overlying suspended top beam on the stoping roadway and the overlying pressure of the suspended rock stratum increase the load during supporting, so the method reasonably controls the ratio of the roadway width of the working surface at one side of the upper section to the roadway width of the working surface at one side of the lower section, and reduces the roadway width of the working surface at one side of the upper section as much as possible, so that the top plate at one side of the upper section is easier to collapse. However, the length and the thickness of the cantilever beam are reduced by matching with a presplitting slot method under the condition of a hard top plate, so that the load transfer proportion from an overlying rock layer of a working face goaf of an upper section to a working face of a lower section is reduced, the mining load added value of the roadway protection wall body can be reduced, and the surrounding rock of a stoping roadway space between the filling wall body and the working face of the lower section is kept stable and cannot deform greatly.
C. And (3) stoping the working face of the lower section, completing stoping of the working face of the upper section and plugging of the connecting roadway, completing tunneling of the stoping roadway of the lower section, completing preparation of the working face of the lower section, and performing stoping of the working face of the lower section.
And in the stoping stage of the working face of the lower section, along with the completion of stoping of the working face of the upper section, the connection roadway is completely plugged, and the filling wall is connected to form a whole. And forming a lower section working face goaf along with the continuous propulsion of the lower section stoping working face until the stoping of the lower section working face is finished. And filling a stoping roadway in the range of the wall body and the lower section working face to serve the lower section working face.
And (5) repeatedly performing excavation of a stoping roadway and stoping of a working face to finish non-pillar mining of a mining area. Wherein, common stoping tunnels and large-section tunnels with pre-built filling walls are respectively arranged on two sides of the first stoping face, and the large-section tunnels with the pre-built filling walls are used for the stoping tunnels of the subsequent working faces until the stoping tunnels of the last adjacent working faces of the mining area are arranged with common tunnels.
In the steps A to C, the excavation of a stoping roadway, the construction of a filling wall body, the stoping of an upper section working face, the presplitting cutting seam, the plugging of a connecting roadway and the stoping construction of a lower section working face are automatically controlled, and the steps A to C are applied to the intelligent mine mining. The construction parameters of all the construction steps are gathered to an intelligent mining system of the mine in combination with the construction of an intelligent mine, particularly, the tunneling of a roadway is automatically constructed by adopting a comprehensive tunneling machine, the construction of a filling wall body is automatically filled by adopting a mine filling system, the stoping of the working face of an upper section uses intelligent mining equipment of the working face, the mining parameters are transmitted to an intelligent control system, a presplitting joint cutter determines the construction according to the comprehensive judgment of the intelligent system, and the plugging of a connecting roadway is completed by using the mine filling system; the steps A to C are applied to intelligent mine mining, so that rock burst disasters can be effectively avoided, and the intelligent mining under special mining conditions is facilitated.
A pillar-free mining method for a pre-built filling wall in a large-section roadway close to a coal seam is characterized in that mining of an upper coal seam is carried out by the pillar-free mining method for the pre-built filling wall in the large-section roadway, and then mining of a lower coal seam is carried out.
The mining in the upper coal seam is specifically as follows: A. excavating a stoping roadway, arranging filling walls in sections behind an excavation head in the excavation stage of the stoping roadway, reserving connecting roadways among sections of the filling walls, and enabling the distance between the filling walls and the working surface of the upper section to be smaller than the distance between the filling walls and the working surface of the lower section; B. stoping the working face of the upper section, sequentially plugging the connecting roadways between the sections completed in front of the stoping working face of the upper section along with the stoping of the working face of the upper section, and simultaneously performing pre-splitting joint cutting in front of the stoping working face of the upper section; C. stoping the working face of the lower section, completing stoping of the working face of the upper section and plugging of the connecting roadway, completing tunneling of the stoping roadway of the lower section, completing preparation of the working face of the lower section, and performing stoping of the working face of the lower section; and (5) repeatedly performing excavation of the stoping roadway and stoping on the working face to finish the pillar-free mining of the mining area.
After the upper coal seam is mined, the formed goaf has no residual coal pillars, and particularly, the stress transmission of the upper coal seam is damaged by the non-pillar mining, so that the complete pressure relief can be realized, the problem of the stress concentration of the coal pillars cannot be caused in the lower coal seam during mining, and the damage of the coal pillar type rock burst can be fundamentally avoided. In addition, the coal seam is fully decompressed by the mining of the upper layer, and the danger of coal rock dynamic disasters is reduced.
The filling wall body is constructed by paste filling, waste filling or masonry wall body, and filling parameters can be selected according to mine practice. The method for mining the coal pillars free of the pre-built filling wall in the large-section roadway is used in the mining of gas mines, rock burst dangerous mines or coal seam groups, so that the mining is finished under the condition of not generating the coal pillars, the loss of the coal pillars in sections is reduced, the tunneling rate and the construction cost of the roadway are reduced, and the coal mining rate of the mines is improved.
The coal pillar-free mining method for pre-building the filling wall body in the large-section roadway is applied to mining of coal beds close to upper and lower layers, so that rock burst disasters caused by coal pillar stress concentration can be avoided, full pressure relief of the coal beds is realized, the air permeability of the coal beds is improved, gas flow of the close coal beds is facilitated under the coal bed group mining condition, and the danger of coal rock dynamic load is reduced. In addition, the method has important significance for improving the safety of the working face and ensuring high-efficiency mining.
It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.