Gob-side roadway composite supporting structure and gob-side roadway composite supporting method

Abstract

The invention provides a gob-side roadway composite supporting structure and a gob-side roadway composite supporting method, and relates to the technical field of gob-side roadway supporting, the gob-side roadway composite supporting structure comprises a side wall supporting body and a grouting space, the side wall supporting body comprises at least one layer of side wall body, and the side wall body is provided with a plurality of prefabricated modules which are spliced with one another; the side wall supporting body can be supported between a top plate and a bottom plate of a roadway. The grouting space is used for being filled with grouting bodies, and the grouting bodies can seal gaps between the prefabricated modules. Along with advancing of the free face, the prefabricated modules are spliced to form the side wall supporting body on the side, close to the goaf, of the roadway behind the free face, the side, close to the goaf, of the roadway can be preliminarily sealed within a shorter time so that formation of an air leakage channel difficult to control can be reduced, and then the grouting space is filled with grouting bodies; and the grouting body can further block gaps between the prefabricated modules, sealing is further conducted, and therefore the safety of the goaf is improved.

Description

Technical Field

[0001] This invention relates to the field of roadway support technology, and in particular to a composite support structure and method for roadways along the goaf. Background Technology

[0002] In coal mining, the technique of leaving roadways along the goaf is commonly used. This can improve the coal recovery rate, reduce the amount of roadway excavation, and alleviate the tension of mining succession. After the roadway is excavated, a support structure is usually installed along the length of the roadway on the side adjacent to the goaf to ensure the structural stability of the roadway. Existing technologies often use flexible formwork support, which involves first erecting two parallel flexible forms made of high-strength woven fabric or composite membrane along the length of the roadway using supports. A closed filling space is formed between the two flexible forms. Then... High-flowability filling material is pumped into the filling space. After the material solidifies quickly, it forms a flexible mold wall with a certain strength and toughness. Although this method uses a fast-solidifying material, it still takes a certain amount of time to set up the support, install the flexible mold, pump the filling material, and for the filling material to solidify and reach the preset strength. Sometimes the roof between the roadway and the goaf will collapse first, forming irregular voids. Subsequent support is not enough to completely fill the voids, resulting in uncontrollable air leakage channels between the roadway and the goaf, which can cause spontaneous combustion and fire in the goaf, creating safety hazards. Summary of the Invention

[0003] The purpose of this invention is to provide a composite support structure and method for goaf-side roadways to solve the technical problems existing in the prior art and improve the safety of goaf areas.

[0004] To achieve the above objectives, the present invention provides the following solution: This invention provides a composite support structure for a goaf-side roadway, comprising: a sidewall support body, wherein the sidewall support body is disposed on the side of the roadway near the goaf and extends along the length of the roadway, the sidewall support body on the side of the roadway near the goaf includes at least one layer of sidewall, each layer of the sidewall includes multiple prefabricated modules spliced ​​together, the sidewall support body can support between the top and bottom slabs of the roadway; and a grouting space, wherein a grouting template is erected on the side of the sidewall support body near the goaf, the grouting template extends along the length of the roadway, the grouting template, the side of the sidewall support body near the goaf, and the bottom slab of the goaf enclose the grouting space, the grouting space is used to fill the grouting body, the grouting body can seal the gaps between the prefabricated modules.

[0005] In some embodiments, the grouting template comprises an inclined baffle and a side baffle, the inclined baffle is inclined from the top end to the bottom end of the sidewall support body towards a direction away from the sidewall support body, the side baffle is used to block the two ends of the grouting space along the length direction of the roadway, the top end of the sidewall support body is provided with a grouting hole, the grouting hole penetrates through the side of the sidewall support body close to the roadway and the side of the sidewall support body close to the goaf, and the grouting hole is used for the grouting pipe to pass through to grout in the grouting space.

[0006] In some embodiments, each of the prefabricated modules is provided with a splicing column or a splicing hole, the splicing column on the prefabricated module can be inserted into the splicing hole of the adjacent prefabricated module to splice the prefabricated modules.

[0007] In some embodiments, the thickness of the sidewall support body perpendicular to the length direction of the roadway is calculated by the following formula: (1) In formula (1): q (MPa) is the support body load, which can be read by a hydraulic support sensor; h (mm) is the effective mining height of the goaf, which can be directly measured; x (mm) is the thickness of the sidewall support body perpendicular to the length direction of the roadway; b B (mm) is the width of the roadway; b C (mm) is the width of the hanging roof on the side of the sidewall support body close to the goaf; is the shear angle of the coal seam of the goaf, (N / mm 3 ) is the specific gravity of the coal seam of the goaf, is the dip angle of the coal seam of the goaf.

[0008] In some embodiments, the sidewall support body comprises a sidewall body on the side of the roadway close to the goaf.

[0009] In some embodiments, the prefabricated module is made of coal gangue, water and cement.

[0010] In some embodiments, the bottom end of the inclined baffle is connected and fixed with the floor of the goaf by a fastener, and the top end of the inclined baffle is connected and fixed with the top end of the sidewall support body by a fastener.

[0011] In some embodiments, the inclined baffle and the side baffle are both spliced by a plurality of baffle units.

[0012] In some embodiments, the quick-setting paste material is made from a mixture of coal gangue, cement, and fly ash.

[0013] The present invention also provides a method for composite support of roadways using the composite support structure for roadways along the goaf described in any of the above claims, comprising the following steps: On the side of the roadway behind the free face that is close to the goaf, the prefabricated modules are spliced ​​together to form the sidewall support, which provides timely support for the roadway roof and initially seals the side of the roadway that is close to the goaf. The grouting body is filled into the grouting space on the side of the sidewall support near the goaf, further sealing the gaps between the prefabricated modules and providing lateral support from the side of the sidewall support near the goaf. As the coal body is mined, the length of the sidewall support and the grouting body is gradually increased.

[0014] The present invention achieves the following technical effects compared to the prior art: This invention provides a composite support structure and method for goaf-side roadways. As the goaf face advances, prefabricated modules are assembled to form a sidewall on the side of the roadway near the goaf behind the goaf face, thus forming a sidewall support. This process, using prefabricated modules for easy transport within the roadway, only requires assembling the modules to support the roadway roof. Compared to flexible formwork support methods, this method can achieve initial sealing of the side of the roadway near the goaf in a shorter time, reducing the risk of damage to the roadway and the goaf. The irregular voids formed by the collapse of the roof between the zones reduce the formation of uncontrollable air leakage channels. Then, a grouting template is erected on the side of the sidewall support near the goaf. The grouting template, the side of the sidewall support near the goaf, and the bottom plate of the goaf enclose the grouting space. Grout is filled into the grouting space. The grout can further seal the gaps between the prefabricated modules, further sealing them to reduce the formation of tiny air leakage channels, reduce the risk of spontaneous combustion and fire in the goaf, and improve the safety of the goaf. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a composite support structure for a roadway along the tunnel in one embodiment of this invention; Figure 2 This is a schematic diagram of the sidewall support structure in one embodiment of this invention; Figure 3 Figure is a schematic diagram of a prefabricated module structure in one embodiment of the present embodiment; Figure 4 Figure is a schematic diagram of a sidewall support structure in another embodiment of the present embodiment; Figure 5 Figure is a schematic diagram of a composite support method along the gob in one embodiment of the present embodiment.

[0017] In the figure: 1 - sidewall support; 11 - prefabricated module; 12 - spliced column; 13 - spliced hole; 14 - grouting hole; 15 - grouting pipeline; 16 - elastic body; 161 - upper roof; 162 - lower roof; 163 - spring; 17 - anchor rod hole; 2 - grouting template; 21 - grouting body; 22 - inclined baffle; 23 - side baffle; 3 - roadway; 5 - bottom module: 51 - first corner block away from the side of the gob; 52 - first intermediate block; 53 - first corner block close to the side of the gob; 6 - middle module: 61 - second corner block away from the side of the gob; 62 - second intermediate block; 63 - second corner block close to the side of the gob; 7 - top module: 71 - third corner block away from the side of the gob; 72 - third intermediate block; 73 - third corner block close to the side of the gob. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0019] The purpose of the present application is to provide a composite support structure along the gob and a composite support method along the gob to solve the technical problems existing in the prior art and improve the safety of the gob.

[0020] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0021] Embodiment one The present embodiment provides a composite support structure along the gob, such as Figures 1-3As shown, the side wall support body 1 is arranged on one side of the roadway 3 close to the goaf and extends along the length direction of the roadway 3, the side wall support body 1 comprises at least one layer of side wall body on the side of the roadway 3 close to the goaf, each layer of side wall body comprises a plurality of prefabricated modules 11 spliced with each other, and the side wall support body 1 can be supported between the roof and the floor of the roadway 3; the grouting formwork 2 is arranged on the side of the side wall support body 1 close to the goaf, the grouting formwork 2 extends along the length direction of the roadway 3, and the grouting formwork 2, the side of the side wall support body 1 close to the goaf and the floor of the goaf enclose the grouting space, the grouting space is used for filling the grouting body 21, and the grouting body 21 can seal the gaps between the prefabricated modules 11; as the working face advances, the prefabricated modules 11 are spliced to form the side wall body on the side of the roadway 3 close to the goaf behind the working face, and then the side wall support body 1 is formed, and in the premise of using the prefabricated modules 11 for facilitating transportation in the roadway 3, the support of the roof of the roadway 3 can be completed only by splicing the prefabricated modules 11, compared with the flexible formwork support method, the side of the roadway 3 close to the goaf can be preliminarily sealed in a shorter time, so as to reduce the irregular cavities formed by the roof collapse between the roadway 3 and the goaf, and then the formation of the uncontrollable air leakage channel is reduced, then the grouting formwork 2 is arranged on the side of the side wall support body 1 close to the goaf, the grouting formwork 2, the side of the side wall support body 1 close to the goaf and the floor of the goaf enclose the grouting space, and the grouting space is filled with the grouting body 21, the grouting body 21 can further seal the gaps between the prefabricated modules 11, further sealing is performed to reduce the formation of the fine air leakage channel, reduce the spontaneous combustion and fire hazards of the goaf, and improve the safety of the goaf.

[0022] In some embodiments of the present embodiment, as shown in Figure 1 As shown, the grouting formwork 2 comprises an inclined baffle 22 and a side baffle 23, the inclined baffle 22 is inclined from the top end to the bottom end of the side wall support body 1 to the direction away from the side wall support body 1, and the side baffle 23 is used for sealing the two ends of the grouting space along the length direction of the roadway 3, the top end of the side wall support body 1 is provided with a grouting hole 14, the grouting hole 14 penetrates through the side of the side wall support body 1 close to the roadway 3 and the side of the side wall support body 1 close to the goaf, and the grouting hole 14 is used for the grouting pipe 15 to pass through to grout in the grouting space, by using the inclined baffle 22 and the side baffle 23, the grouting space is formed between the side wall support body 1 and the floor of the goaf, and the inclined baffle 22 is inclined from the top end to the bottom end of the side wall support body 1 to the direction away from the side wall support body 1, the grouting body 21 with a triangular cross section is provided, the grouting body 21 is more stable, the damage of the grouting body 21 caused by the impact of the coal gangue falling from the roof of the goaf in the later period is reduced, and then the influence of the damage of the grouting body 21 on the sealing effect of the gaps between the prefabricated modules 11 is reduced.

[0023] In some embodiments of the present embodiment, the side wall support body 1 is provided with only one layer of side wall bodies on one side of the roadway 3 close to the goaf, so as to improve the speed of splicing of the prefabricated modules 11 and shorten the forming time of the side wall support body 1. In another embodiment of the present embodiment, the prefabricated modules 11 perpendicular to the length direction of the roadway 3 are arranged in two rows, and the horizontal gaps and the vertical gaps of the two rows of prefabricated modules 11 are staggered with each other, so as to avoid forming a continuous air leakage channel.

[0024] In some embodiments of the present embodiment, the prefabricated modules 11 are provided with splicing columns 12 or splicing holes 13, the splicing columns 12 on the prefabricated modules 11 can be inserted into the splicing holes 13 of the adjacent prefabricated modules 11 to splice the prefabricated modules 11, thereby enhancing the stability of the side wall support body 1.

[0025] Specifically, as shown in Figure 3 the prefabricated modules 11 are provided with splicing columns 12 and splicing holes 13, the sizes of the splicing columns 12 and the splicing holes 13 are the same, the shapes of the splicing columns 12 and the splicing holes 13 can be matched, and each row of prefabricated modules 11 includes a bottom layer module 5, a top layer module 7 and an intermediate layer module 6. In the bottom layer module 5, the bottom layer module 5 includes a first corner block 51 away from the goaf side, a first intermediate block 52 and a first corner block 53 close to the goaf side, the intermediate layer module 6 includes a second corner block 61 away from the goaf side, a second intermediate block 62 and a second corner block 63 close to the goaf side, and the top layer module 7 includes a third corner block 71 away from the goaf side, a third intermediate block 72 and a third corner block 73 close to the goaf side. The top surface of the first corner block 51 away from the goaf side and the side close to the goaf side are provided with splicing columns, the top surfaces of all the first intermediate blocks 52 are provided with splicing columns, the sides away from the goaf side are provided with splicing holes, and the sides close to the goaf side are provided with splicing columns. The top surface of the first corner block 53 close to the goaf side is provided with a splicing column, and the side away from the goaf side is provided with a splicing hole. In the intermediate layer module 6, the top surface of the second corner block 61 away from the goaf side and the side close to the goaf side are provided with splicing columns, and the bottom surface is provided with a splicing hole. The top surfaces of all the second intermediate blocks 62 are provided with splicing columns, the sides away from the goaf side are provided with splicing holes, the sides close to the goaf side are provided with splicing columns, and the bottom surface is provided with a splicing hole. The top surface of the second corner block 63 close to the goaf side is provided with a splicing column, and the bottom surface and the side away from the goaf side are provided with splicing holes. In the top layer module 7, the bottom surface of the third corner block 71 away from the goaf side is provided with a splicing hole, and the side close to the goaf side is provided with a splicing column. The bottom surfaces and the sides away from the goaf side of all the third intermediate blocks 72 are provided with splicing holes, and the sides close to the goaf side are provided with corresponding splicing columns. The bottom surface and the side away from the goaf side of the third corner block 73 close to the goaf side are provided with splicing holes.

[0026] In some embodiments of the present embodiment, the thickness of the side wall support body perpendicular to the length direction of the roadway is calculated by the following formula: (1) In formula (1): q (MPa) is the support structure load, which can be read by a hydraulic support sensor; h (mm) is the effective mining height of the goaf, which can be directly measured; x (mm) is the thickness of the side wall support body 1 perpendicular to the length direction of the roadway 3; b B (mm) is the width of the roadway, which can be directly measured; b C (mm) is the width of the suspended roof on the side of the side wall support body 1 close to the goaf, which can be directly measured; is the shear angle of the goaf coal seam, (N / mm 3 ) is the specific gravity of the goaf coal seam, is the inclination angle of the goaf, wherein the shear angle , the specific gravity (N / mm 3 ) of the goaf coal seam, and the inclination angle of the goaf can be obtained from a geotechnical engineering survey report.

[0027] In some embodiments of the present embodiment, the prefabricated module 11 is made of coal gangue, water and cement, wherein the coal gangue is a byproduct of waste gangue in the coal mining process, without the need to transport building materials from the surface, with lower cost investment, and can complete the solid waste disposal of waste gangue.

[0028] In some embodiments of the present embodiment, as shown in Figure 4 , the side wall support body 1 further comprises a plurality of elastic bodies 16 arranged on the top of the side wall body, the elastic body 16 comprising an upper roof 161, a lower bottom plate 162 and a circumferential side wall soft sleeve, the upper roof 161 and the lower bottom plate 162 being connected by a spring 163, the plurality of elastic bodies being arranged along the extension direction of the side wall body, a predetermined height being reserved between the top of the side wall body and the roadway roof when the side wall body is erected, the predetermined height being less than the height of the elastic body 16, and the elastic body 16 being arranged between the top of the side wall body and the roadway roof, so that the side wall support body better adapts to the uneven deformation of the roadway roof after the advancement of the free face.

[0029] In some embodiments of the present embodiment, the bottom end of the inclined baffle 22 is fixedly connected with the floor of the goaf by fasteners, the top end of the inclined baffle 22 is fixedly connected with the top end of the sidewall support body 1 by fasteners, and the side baffle 23 is also fixedly connected with the sidewall support body 1, the inclined baffle 22 and the floor of the goaf by fasteners respectively, so as to form a stable grouting body. Since the grouting body 21 adopts a paste material with high consistency, even if the gap between the inclined baffle 22, the side baffle 23, the sidewall support body 1 and the goaf is not sealed, the paste material will not leak out of the gap to form the grouting body 21.

[0030] In some embodiments of the present embodiment, the inclined baffle 22 and the side baffle 23 are both composed of a plurality of baffle units, and the edges of adjacent baffle units can be provided with matching stepped surfaces to realize mutual splicing. By using the spliced baffle units, transportation in the roadway 3 is facilitated.

[0031] In some embodiments of the present embodiment, as shown in Figure 4 , the sidewall support body 1 is also provided with an anchor rod hole, the anchor rod hole penetrates through the side of the sidewall support body 1 close to the roadway 3 and the side of the sidewall support body 1 close to the goaf, and the through anchor rod is sequentially inserted through the inclined baffle 22 and the sidewall support body 1, so as to improve the stability of the inclined baffle 22.

[0032] In some embodiments of the present embodiment, the grouting body 21 is made of a rapid-setting paste material, which is mixed by coal gangue, cement, fly ash and a rapid-setting agent. The rapid-setting paste material can complete initial setting in 5-10 minutes, so as to seal the gap between the prefabricated modules 11.

[0033] Embodiment Two The present embodiment provides a method for using the composite support structure along the gob roadway in the embodiment one, as shown in Figure 5 , comprising the following steps: Reading the support body load by the hydraulic support q (MPa), measuring the effective mining height of the goaf h (mm), the width of the roadway b B (mm) and the width of the hanging roof on the side of the sidewall support body close to the goaf b C (mm), according to the geotechnical engineering investigation report, obtaining the shear angle of the coal seam of the goaf , the specific gravity of the coal seam of the goaf (N / mm 3 ), the inclination of the coal seam of the goaf , substituting into formula (1) to obtain the thickness of the sidewall support body perpendicular to the length direction of the roadway x (mm); The layers of the side wall body near the goaf side of the roadway are selected to prefabricate the prefabricated module 11; with the advancement of the free face, the prefabricated module 11 is spliced to form the side wall body on the side of the roadway 3 near the goaf behind the free face; A preset height is reserved between the side wall body top and the roadway roof, and the elastic body 16 is arranged between the side wall body top and the roadway roof, and a plurality of elastic bodies are arranged along the extension direction of the side wall body; On the side of the side wall support body 1 near the goaf, the inclined baffle 22 and the side baffle 23 are spliced through the baffle unit, and the inclined baffle 22, the side baffle 23, the side wall support body 1 and the floor of the goaf are enclosed to form a grouting space, wherein the inclined baffle 22 is inclined from the top end to the bottom end of the side wall support body 1 to the direction away from the side wall support body 1, and the side baffle 23 is used to block the two ends of the grouting space along the length direction of the roadway 3; The through anchor rod is sequentially passed through the inclined baffle 22 and the side wall support body 1; The grouting body 21 is injected into the grouting space on the side of the side wall support body 1 near the goaf to form a grouting body 21, further block the gap between the prefabricated modules 11, and provide lateral support from the side of the side wall support body 1 near the goaf; With the mining of the coal body, the free face gradually advances forward, and the length of the side wall support body 1 and the grouting body is gradually increased, and when the length of the side wall support body 1 is increased, the prefabricated module 11 is directly spliced on the end of the existing side wall support body 1 near the free face; When the length of the grouting body is increased, the inclined baffle 22 does not need to be removed, only the side baffle 23 at the end of the existing grouting space near the free face needs to be removed, and the inclined baffle 22, the side baffle 23, the side wall support body 1 and the floor of the goaf are continued to be enclosed to increase the length of the grouting space; specifically, the free face advances 3m, the side wall support body 1 and the grouting body of 3m are increased at the end near the free face, so as to reduce the irregular cavity formed by the roof collapse between the roadway 3 and the goaf.

[0034] The specific examples are applied in the application to illustrate the principles and implementation modes of the application; the above examples are only used to help understand the method and core idea of the application; meanwhile, for those skilled in the art, according to the idea of the application, the specific implementation mode and application range will be changed. In conclusion, the content of the specification should not be understood as a limitation of the application.

Claims

1. A composite support structure for a gob-side entry, characterized by, Comprise: A side wall support body is arranged at one side of the roadway close to the goaf and extends along the length direction of the roadway, the side wall support body comprises at least one layer of side wall body at one side of the roadway close to the goaf, each layer of side wall body comprises a plurality of prefabricated modules spliced with each other, and the side wall support body can be supported between the roof and floor of the roadway; A grouting space is arranged on one side of the side wall support body close to the goaf, the grouting template extends along the length direction of the roadway, the grouting template and one side of the side wall support body close to the goaf and the floor of the goaf enclose a grouting space, the grouting space is used for filling a grouting body, and the grouting body can seal the gaps between the prefabricated modules.

2. The gob-side entry composite support structure according to claim 1, wherein The grouting template comprises an inclined baffle and a side baffle, the inclined baffle is inclined from the top end to the bottom end of the side wall support body to the direction away from the side wall support body, the side baffle is used for blocking the two ends of the grouting space along the length direction of the roadway, the top end of the side wall support body is provided with a grouting hole, the grouting hole penetrates one side of the side wall support body close to the roadway and one side of the side wall support body close to the goaf, and the grouting hole is used for the grouting pipe to pass through to grout the grouting space.

3. The gob-side entry composite support structure according to claim 1, wherein Each prefabricated module is provided with a splicing column or a splicing hole, the splicing column on the prefabricated module can be inserted into the splicing hole of the adjacent prefabricated module to splice each prefabricated module.

4. The gob-side entry composite support structure according to claim 1, wherein The thickness of the side wall support body perpendicular to the length direction of the roadway is calculated by the following formula: （1） In formula (1): q (MPa) is the support body load, which can be read by a hydraulic support sensor; h (mm) is the effective mining height of the goaf, which can be directly measured; x (mm) is the thickness of the sidewall support body perpendicular to the length direction of the roadway; b B (mm) is the width of the roadway; b C W (mm) is the width of the hanging roof near the side of the gob of the side wall support body; is the shear angle of the coal seam of the gob, (N / mm 3 ) is the specific gravity of the coal seam of the gob, is the dip angle of the coal seam of the gob.

5. The gob-side entry composite support structure according to claim 1, wherein The side wall support body comprises one layer of side wall body at one side of the roadway close to the goaf.

6. The gob-side entry composite support structure according to claim 1, wherein The prefabricated module is made of coal gangue, water and cement.

7. The gob-side entry composite support structure according to claim 2, wherein The bottom end of the inclined baffle is connected and fixed with the floor of the goaf through a fastener, and the top end of the inclined baffle is connected and fixed with the top end of the side wall support body through a fastener.

8. The gob-side entry composite support structure according to claim 7, wherein The inclined baffle and the side baffle are spliced by a plurality of baffle units.

9. The gob-side entry composite support structure according to claim 1, wherein The grouting body is made of a quick-setting paste material, and the quick-setting paste material is made of coal gangue, cement and fly ash.

10. A method of gob-side entry composite support using the gob-side entry composite support structure according to any one of claims 1 to 9, characterized by, Comprise the following steps: The prefabricated modules are spliced to form the side wall support body at one side of the roadway close to the goaf behind the empty surface, the roof of the roadway is timely supported, and one side of the roadway close to the goaf is preliminarily sealed; The grouting space on one side of the side wall support body close to the goaf is filled with the grouting body, the gaps between the prefabricated modules are further blocked, and lateral support can be provided from one side of the side wall support body close to the goaf; With the mining of the coal body, the length of the side wall support body and the grouting body is gradually increased.

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