Roadway forming method by expanding excavating and filling gangue paste in thick coal seam

Abstract

Provided is a method of forming a roadway by filling gangue paste during wide roadway excavation of a thick coal seam belonging to the technical field of mining industry. The method comprises: firstly designing a width of a filing strip and a width of a new excavation roadway according to a geological condition of a coal seam; secondly, determining a length of each filling, i.e. a cyclic filling interval, according to an existing excavation technical condition of a mining shaft; when the new excavation roadway is excavated, performing supporting for a roof, a floor and an inner side of a roadway by using a strong bolt and bolt-mesh-cable; then, after the new excavation roadway is excavated for the cyclic filling interval, starting to perform roadway-expanding excavation along an outer side of the roadway; when roadway-expanding excavation is performed, performing temporary supporting for a filling strip and a junction of the filling strip and the new excavation roadway by using a single hydraulic prop in cooperation with a metal articulated roof beam; finally, after roadway-expanding excavation is completed, removing temporary supports and filling the filling strip; afterwards, the above steps are performed alternately. In this way, coal losses caused by reserving coal pillars can be effectively reduced, the impact of the underground pressure during roadway excavation is relieved and the costs of gangue treatment and roadway excavation are lowered.

Claims

1. A roadway forming method by expanding excavation and filling gangue paste in a thick coal seam, sequentially comprising the steps of: a. designing a width of a filling strip and a width of a new excavation roadway according to a geological condition of the thick coal seam; b. determining a cyclic filling interval as a length of each filling; c. after the new excavation roadway is excavated for the cyclic filling interval, starting to perform the expanding excavation along an outer side of the new excavation roadway to generate the filling strip; when the new excavation roadway is excavated, using a bolt and a bolt-mesh-cable as a support to support a roof, a floor and an inner side of the new excavation roadway; when the expanding excavation is performed, using a single hydraulic prop in cooperation with a metal articulated roof beam as a temporary support to support the filling strip formed and a junction of the filling strip and the new excavation roadway; d. after the expanding excavation is completed, removing the temporary support and constructing an isolation wall with a double-layer plastic woven fabric at a side of the filling strip; after the isolation wall is constructed, filling the filling strip through a filling pipeline, wherein the filling pipeline transports the gangue paste to the filling strip; and e. performing steps a-d repeatedly; wherein the thick coal seam refers to a stable coal seam has a thickness of greater than 3.5 m and less than 10 m when underground mining, an inclination angle of less than 12 degrees, and has no fault.

2. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein a plurality of the metal articulated roof beams are articulated together from front, back, left and right to form a stable one-piece body with a plurality of the single hydraulic prop.

3. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein the single hydraulic prop is provided with a base.

4. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein, at step d, timber pillars are firstly used to support the filling strip before the temporary support is removed.

5. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein in step d, the filling strip filled replaces a coal pillar for protection.

6. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 5, wherein in step d, the filling strip filled replaces the coal pillar between working faces configured to achieve coal-pillar-free excavation.

7. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein in step d, the filling strip is paralleled to the new excavation roadway.

8. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 7, wherein a height of the filling strip is equal to a height of the new excavation roadway.

9. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein in step d, filling the filling strip is through the filling pipeline in the new excavation roadway.

10. The roadway forming method by expanding excavation and filling gangue paste in the thick coal seam according to claim 1, wherein the roadway forming method is performed during first-mining.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present disclosure will be described further below in combination with the accompanying drawings.

(2) FIG. 1 is a principle diagram illustrating a method of performing wide roadway excavation in a thick coal seam according to an example of the present disclosure.

(3) FIG. 2 is an A-A section view (filling is completed) of FIG. 1 of the present disclosure.

(4) FIG. 3 is a B-B section view (roadway-expanding excavation is completed and filling is to be performed) of FIG. 1 of the present disclosure.

(5) FIG. 4 is a C-C section view (excavation of a new excavation roadway) of FIG. 1 of the present disclosure.

(6) In the drawings, 1 refers to a new excavation roadway, 2 refers to a filling strip, 3 refers to a single hydraulic prop, 4 refers to a metal articulated roof beam, 5 refers to a strong bolt, 6 refers to an isolation wall, 7 refers to a filling pipeline, 8 refers to an outer side of a roadway, 9 refers to an inner side of a roadway, 10 refers to a roof, 11 refers to a floor and L refers to a cyclic filling interval.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(7) The present disclosure provides a system of filling gangue paste during wide-roadway excavation of a thick coal seam. To make the advantages and technical combination with specific examples.

(8) Descriptions are made below in combination with FIGS. 1-4.

(9) At step 1, it is determined that a filling strip 2 has a width of 9 m and a new excavation roadway 1 has a width of 4 m according a geological condition of a coal seam.

(10) At step 2, a cyclic filling interval L is determined as 14 m according to an existing excavation technical condition. When the new excavation roadway 1 is excavated in a coal seam, a section size of the roadway is 4 m in width and 3 m in height. To ensure roadway stability, a strong bolt 5 is hammered for supporting while the new excavation roadway 1 is excavated. The bolt supporting refers to that strong bolts and cables are hammered on a roof 10, a floor 11, and an inner side 9 of the roadway and a rhombic wire mesh is hung on the tail of the bolt to reinforce the supporting effect.

(11) When the new excavation roadway 1 is excavated to a length of 14 m, excavation of 14 m is performed along an outer side 8 of the roadway to form the filling strip 2 of 9 m. When a roadway-expanding excavation is performed, it is ensured that a space generated by the roadway-expanding excavation is paralleled to the new excavation roadway 1. After the roadway-expanding excavation is started, the excavation of the new excavation roadway 1 and the roadway-expanding excavation are alternately performed to advance cyclically, that is, the new excavation roadway 1 is excavated firstly for one segment, and then the roadway-expanding excavation is performed, so that a distance of the new excavation roadway 1 and an end of the filling strip 2 is maintained between 13-15 m.

(12) At step 3, when the roadway-expanding excavation is performed, temporary supporting is performed for the formed filling strip 2 and a junction of the filling strip 2 and the new excavation roadway 1 by using the single hydraulic prop 3 in cooperation with a metal articulated roof beam 4. The single hydraulic prop wears shoes. The metal articulated roof beams 4 are articulated together from front, back, left and right to form a stable one-piece body. After the temporary supporting is completed, a filling pipeline 7 is arranged in the new excavation roadway 1.

(13) At step 4, after the roadway-expanding excavation is completed, the temporary supports are removed, dense timber supports are used for supporting at a side of the filling strip 2 and then an isolation wall 6 is constructed with a plastic woven fabric to form a closed filling space. The isolation wall 6 may be constructed based on the following measures: the plastic woven fabric is 20 m long and 4 m wide, a double-layer plastic woven fabric with a straw curtain rolled at an upper part is used and bound tightly with 15# iron wire at a spacing of 140 mm and then fixed on a timber pillar with an allowance of 1 m left at the bottom, and folded inwardly, and the allowance is compacted with woven bags fully loaded with gangues along the woven fabric after float coals on the floor are cleaned. It is guaranteed that the plastic woven fabric and the floor of a region to be filled are tightly attached.

(14) After the filling isolation wall 6 is constructed, the gangue paste prepared by a filling station on the ground is filled into the filling strip 2 through the filling pipeline 7 in the new excavation roadway 1.

(15) Afterwards, the above steps are performed alternately.

(16) The present disclosure solves the problems that severe losses of coals are caused by reserving roadway-protection coal pillars in a traditional thick coal seam, the coal pillars are easily crisped or even crushed due to the impact of underground pressure during a gob or roadway excavation, easily resulting in spontaneous combustion of coal pillars in the gob, and imposing safety threat to the safe production and so on. Also, the combination of the filling mining technology and the gob-side roadway formation technology solves the problems of high costs of treatment for a large quantity of gangues produced during thick coal seam mining and harms caused to the environment and so on while improving the working efficiency and lowering production costs.

(17) A part that is not mentioned in the present disclosure may be implemented by the prior art.

(18) Although terms such as the single hydraulic prop and the metal articulated roof beam are used frequently in the present disclosure, the possibility of using other terms is not precluded. Simple substitutions made by those skilled in the art for these terms according to the teachings of the present disclosure shall all fall within the scope of protection of the present disclosure.