Coal mine goaf site construction method

Abstract

The embodiment of the invention provides a coal mine goaf site construction method. The coal mine goaf site construction method comprises the steps that according to the influence degree of a goaf on engineering construction and the influence degree of the engineering construction on the goaf, the suitability of the goaf site is divided into three grades of suitability, basic suitability and poor suitability; the first area corresponding to the suitable level is used for constructing at least one of industrial buildings, commercial buildings, public facilities, high-rise residences and infrastructures, and the second area corresponding to the basic suitable level is used as at least one of agricultural land, forestry land and ecological tourism land. The third area corresponding to the poor suitability level is used for implementing at least one of ecological buffering, vegetation restoration, ecological protection and ecological restoration. According to the coal mine goaf site construction method, treatment, land utilization and ecological restoration of the coal mine goaf site are achieved.

Description

Technical Field

[0001] The invention relates to the field of coal mine goaf treatment, and in particular to a coal mine goaf site construction method. Background Art

[0002] Goafs are formed by the mining of coal resources, leaving a large area of ​​empty space underground, which has a significant impact on engineering construction. In related technologies, the suitability of engineering construction in coal goaf sites is evaluated based on the stability of coal goafs, the impact of coal goafs on engineering construction, and the impact of engineering construction on coal goafs. However, the suitability evaluation results of coal goaf sites and how to construct areas with different suitability evaluation results are still unclear. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention proposes a method for constructing a coal mine goaf area site.

[0005] The method for constructing a coal mine goaf area in an embodiment of the present invention includes:

[0006] According to the influence of goaf on engineering construction and the influence of engineering construction on goaf, the suitability of goaf site is divided into three levels: suitable, basically suitable and poor suitability. Among them, the suitable level includes the influence of goaf on engineering construction is small and the influence of engineering construction on goaf is small. The basically suitable level includes the influence of goaf on engineering construction is medium and the influence of engineering construction on goaf is medium. The poor suitability level includes the influence of goaf on engineering construction is large and the influence of engineering construction on goaf is large.

[0007] The first area of ​​the goaf site corresponding to the appropriate level is used for constructing at least one of industrial buildings, commercial buildings, public facilities, high-rise residential buildings, and infrastructure;

[0008] The second area of ​​the goaf site corresponding to the basic suitability level is used as at least one of agricultural land, forestry land, and eco-tourism land;

[0009] The third area of ​​the goaf site corresponding to the poor suitability level is used to implement at least one of ecological buffering, vegetation restoration, ecological protection, and ecological restoration.

[0010] The coal mine goaf site construction method of the embodiment of the present invention divides the suitability of the goaf site into three levels: suitable, basically suitable and poor suitability, and divides the goaf site into areas with different construction types according to the three levels of suitability. Construction personnel carry out construction in the area according to the corresponding construction types to complete the site construction of the coal mine goaf, thereby realizing the management, land utilization and ecological restoration of the coal mine goaf site.

[0011] In some embodiments, the coal mine goaf site construction method further includes:

[0012] The goaf of the sub-area in the first area for constructing industrial buildings and commercial buildings is filled by at least one of high-pressure grouting, penetration grouting, segmented grouting, layered grouting and intermittent grouting;

[0013] The goaf of the sub-area in the first area for the construction of public facilities and high-rise residential buildings is filled with fine grouting;

[0014] The goaf of the sub-area in the first area for infrastructure construction is filled by high pressure grouting or infiltration grouting.

[0015] In some embodiments, the coal mine goaf site construction method further includes:

[0016] In the sub-area of ​​the first area for constructing industrial buildings and commercial buildings, at least one of pile foundation, raft foundation and underground continuous wall is provided for the corresponding buildings;

[0017] At least one of a settlement joint, a sliding bearing, a seismic isolation device, a protective wall, an isolation belt, a prestressed anchor rod, and an underground continuous wall is provided in the sub-area for building public facilities and high-rise residential buildings in the first area;

[0018] In the first area, a sub-area corresponding to a building for constructing infrastructure is provided with detection equipment to detect the grouting area.

[0019] In some embodiments, the coal mine goaf site construction method further includes:

[0020] In the sub-area of ​​the second area used as agricultural land and forestry land, grouting is performed on the mined-out area, and soil reinforcement and / or ground compaction are performed on the surface;

[0021] In the sub-area of ​​the second area used as eco-tourism land, grouting filling is performed on the goaf, and pile foundation treatment and / or foundation reinforcement is implemented on the surface subsidence area.

[0022] In some embodiments, the coal mine goaf site construction method further includes:

[0023] In the sub-area of ​​the second area used as agricultural land and forestry land, at least one of organic matter, trace elements and soil conditioners is applied to the soil, and at least one of drought-tolerant crops, nitrogen-fixing plants and pioneer tree species is planted;

[0024] In the sub-area of ​​the second area used as ecotourism land, wetlands are constructed in the surface subsidence area with water bodies, and aquatic plants and / or microorganisms are released into the water bodies in the surface subsidence area.

[0025] In some embodiments, the coal mine goaf site construction method further includes:

[0026] In the sub-area of ​​the third area for implementing ecological buffer, at least one of reinforced soil, soil solidification, ecological bags, ecological slope protection, artificial water replenishment, and artificial fertilization is implemented on the surface, and protective forests and / or meadows are planted;

[0027] In the sub-area of ​​the third area for implementing vegetation restoration, grouting is performed on the goaf, soil reinforcement is performed on the surface, and organic fertilizers and / or microbial agents are applied to the soil;

[0028] In the sub-area of ​​the third area used for implementing ecological protection and ecological restoration, reinforced soil is implemented on the surface, micro-disturbance foundation treatment is performed on the corresponding buildings, and vegetation restoration and / or wetland restoration is implemented.

[0029] In some embodiments, the coal mine goaf site construction method further includes: setting physical monitoring sensors and ecological monitoring sensors in the first area, the second area and the third area.

[0030] In some embodiments, the coal mine goaf site construction method further includes:

[0031] According to the load critical influence depth H D The impact of construction on the goaf is divided into three levels: large, medium and small. D The impact of engineering construction on the goaf is great. D ≤H≤1.5H D The impact of engineering construction on the goaf is moderate, and when H>1.5H D The impact of construction on the goaf is small; and / or

[0032] According to the additional stress influence depth H a and the depth of the collapsed water-conducting fracture zone H lf The impact of engineering construction on the goaf is divided into three levels: large, medium and small. lf <H a The impact of engineering construction on the goaf is great. a≤H lf <2.0H a The impact of engineering construction on the goaf is moderate. lf ≥2.0H a The impact of engineering construction on the goaf is small.

[0033] In some embodiments, the coal mine goaf site construction method further includes:

[0034] The influence of goaf on engineering construction is divided into three levels: large, medium and small according to the residual deformation value of the surface of the goaf. The residual deformation value of the surface includes the residual subsidence value W, the residual inclination value i, the residual horizontal deformation value ε and the residual curvature value K. When W>200mm, i>10mm / m, ε>6mm / m and K>0.6×10 -3 / m, the impact of the goaf on engineering construction is great. When 100mm≤W≤200mm, 3mm / m≤i≤10mm / m, 2mm / m≤ε≤6mm / m and 0.2×10 -3 / m≤ε≤0.6×10 -3 / m, the influence of goaf on engineering construction is moderate. When W < 100 mm, i < 3 mm / m, ε < 2 mm / m and K < 0.2 × 10 -3 / m When the goaf has little impact on engineering construction;

[0035] According to the goaf depth H and goaf thickness M, the impact of the goaf on engineering construction is divided into three levels: large, medium and small. When H < 50m or H / M < 30, the impact of the goaf on engineering construction is large; when 50m ≤ H ≤ 200m or 30 ≤ H / M ≤ 80, the impact of the goaf on engineering construction is medium; when H > 200m or H / M > 80, the impact of the goaf on engineering construction is small; and

[0036] The influence of goaf on engineering construction is divided into three levels: large, medium and small according to the stability of goaf site and the deformation requirements of engineering buildings. The deformation requirements of engineering buildings include the absolute value of horizontal deformation value |ε|, the absolute value of inclination value |i| and the absolute value of curvature value |K|.

[0037] When the stability of the goaf is stable, under the conditions of |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / mWhen at least one of the above conditions is met, the impact of the goaf on engineering construction is small.

[0038] When the stability of the goaf is basically stable, the stability of the goaf is basically stable when |ε|>6mm / m, |i|>10mm / m and |K|>0.6×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m<|K|≤0.6×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / mWhen at least one of the above conditions is met, the impact of the goaf on engineering construction is small.

[0039] When the stability of the goaf is unstable, the stability of the goaf is unstable when |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m, when at least one of the above is true, the impact of the goaf on the engineering construction is moderate;

[0040] At least one of .

[0041] In some embodiments, the coal mine goaf site construction method further includes:

[0042] According to the final mining time t of the goaf, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. When t>1.2T and t>730d, the stability of the goaf site is stable; when 0.8T≤t≤1.2T and t>365d, the stability of the goaf site is basically stable; when t<0.8T or t≤365d, the stability of the goaf site is unstable, where T is the duration of surface movement, which is an integer number of days;

[0043] According to the surface deformation characteristics, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. The goaf site stability is stable when the surface is continuously deformed, located in the middle area of ​​the basin, without ground fissures, steps and collapse pits. The goaf site stability is basically stable when the surface is continuously deformed, located in the edge of the basin, with ground tilt and / or ground fissures. The goaf site stability is unstable when the surface is discontinuously deformed, of the pumping or cutting type, with collapse pits or steps on the ground.

[0044] According to the residual deformation value of the surface, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. -3 / m and W<100mm, the stability of the goaf is stable; when 3mm / m≤i≤6mm / m, 2mm / m≤ε≤4mm / m, 0.2×10 -3 / m≤ε≤0.4×10 -3 / m and 100mm≤W≤300mm, the stability of the goaf is basically stable. -3 / m and W>300mm, at least one of them is considered unstable; and

[0045] According to the overburden type and goaf depth ratio H / M, the goaf site stability is divided into three levels: stable, basically stable and unstable.

[0046] When the overburden type is weak rock, the stability of the goaf is stable when H / M>120, the stability of the goaf is basically stable when 120≤H / M≤100, and the stability of the goaf is unstable when H / M<100.

[0047] When the overburden type is medium hard rock, the stability of the goaf is stable when H / M>100, the stability of the goaf is basically stable when 100≤H / M≤80, and the stability of the goaf is unstable when H / M<80.

[0048] When the overburden type is hard rock, the stability of the goaf is stable when H / M>80, basically stable when 80≤H / M≤60, and unstable when H / M<60;

[0049] At least one of . DETAILED DESCRIPTION

[0050] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0051] The following describes a method for constructing a coal mine goaf site according to an embodiment of the present invention.

[0052] The method for constructing a coal mine goaf site in an embodiment of the present invention includes: dividing the suitability of the goaf site into three levels: suitable, basically suitable and poor suitability according to the degree of influence of the goaf on engineering construction and the degree of influence of engineering construction on the goaf, wherein the suitable level includes the small degree of influence of the goaf on engineering construction and the small degree of influence of engineering construction on the goaf, the basically suitable level includes the medium degree of influence of the goaf on engineering construction and the medium degree of influence of engineering construction on the goaf, and the poor suitability level includes the large degree of influence of the goaf on engineering construction and the large degree of influence of engineering construction on the goaf.

[0053] The first area of ​​the goaf site corresponding to the suitability level is used to build at least one of industrial buildings, commercial buildings, public facilities, high-rise residential buildings, and infrastructure. The second area of ​​the goaf site corresponding to the basic suitability level is used as at least one of agricultural land, forestry land, and ecotourism land. The third area of ​​the goaf site corresponding to the poor suitability level is used to implement at least one of ecological buffering, vegetation restoration, ecological protection, and ecological restoration.

[0054] In other words, the goaf site is divided into at least one of the first area, the second area and the third area according to the level of suitability. The first area corresponds to the suitability level, the second area corresponds to the basic suitability level, and the third area corresponds to the poor suitability level. The first area is used to build at least one of industrial buildings, commercial buildings, public facilities, high-rise residential buildings, and infrastructure. The second area is used as at least one of agricultural land, forestry land, and ecotourism land. The third area is used to implement at least one of ecological buffering, vegetation restoration, ecological protection, and ecological restoration. Therefore, the suitability of the first area, the second area, and the third area decreases, and the construction intensity decreases.

[0055] The coal mine goaf site construction method of the embodiment of the present invention divides the suitability of the goaf site into three levels: suitable, basically suitable and poor suitability, and divides the goaf site into areas with different construction types according to the three levels of suitability. Construction personnel carry out construction in the area according to the corresponding construction types to complete the site construction of the coal mine goaf, thereby realizing the management, land utilization and ecological restoration of the coal mine goaf site.

[0056] In some embodiments, the method for construction of coal mine goaf area in the embodiment of the present invention also includes that the goaf area of ​​the sub-area in the first area used for the construction of industrial buildings such as factories, warehouses and commercial buildings such as shopping malls is filled with at least one of high-pressure grouting, penetration grouting, segmented grouting, layered grouting and intermittent grouting, and the grouting material includes at least one of cement slurry, fly ash slurry, polymer slurry and at least one of water reducer, quick setting agent and expansion agent. The goaf area of ​​the sub-area in the first area used for the construction of public facilities such as schools, hospitals, parks and high-rise residential buildings is filled with fine grouting, and the fine grouting includes at least one of low-pressure penetration grouting and micro-grouting. The goaf area of ​​the sub-area in the first area used for the construction of infrastructure such as roads, bridges, water supply and drainage systems is filled with high-pressure grouting or penetration grouting, and the grouting material can be the same as or different from the grouting material of the sub-area used for the construction of industrial buildings and commercial buildings.

[0057] The first area is further divided into sub-areas according to the type of building, and each sub-area implements a corresponding grouting process according to the type of building to be built to ensure that the bearing capacity and stability of the foundation can support the corresponding type of building while having high economic efficiency.

[0058] In some embodiments, the method for construction of coal mine goaf area in the embodiment of the present invention further includes setting at least one of pile foundation, raft foundation and underground continuous wall in the sub-area corresponding to the building for the construction of industrial buildings and commercial buildings in the first area. Setting at least one of settlement joint, sliding bearing, seismic isolation device, protective wall, isolation belt, prestressed anchor rod and underground continuous wall in the sub-area corresponding to the building for the construction of public facilities and high-rise residential buildings in the first area. Setting detection equipment to detect grouting area in the sub-area corresponding to the building for the construction of infrastructure in the first area.

[0059] The first area is further divided into sub-areas according to the types of buildings, and each sub-area implements corresponding foundation reinforcement measures according to the type of building to be built to ensure that the bearing capacity and stability of the foundation can support the corresponding type of building while having high economic efficiency.

[0060] In some embodiments, the method for constructing a coal mine goaf area in an embodiment of the present invention further includes grouting and filling the goaf in a sub-area in the second area used as agricultural land and forestry land, and implementing reinforced soil and / or ground compaction on the surface. In a sub-area in the second area used as ecotourism land, grouting and filling the goaf, and implementing pile foundation treatment and / or foundation reinforcement on the surface subsidence area.

[0061] The second area is further divided into sub-areas according to the construction purpose. All sub-areas need to be grouting-filled to ensure that the bearing capacity and stability of the foundation can support the buildings and crops of corresponding purposes. At the same time, each sub-area implements corresponding foundation reinforcement measures according to the construction purpose to further ensure the bearing capacity and stability of the foundation while having high economic efficiency.

[0062] In some embodiments, the method for constructing a coal mine goaf area in an embodiment of the present invention also includes applying at least one of organic matter, trace elements and soil conditioners to the soil in a sub-area in the second area used as agricultural land and forestry land to improve the soil, planting at least one of drought-tolerant crops, nitrogen-fixing plants and pioneer tree species, preferably using a variety of planting methods such as mixed forests, crop rotation, and intercropping to improve the stability and biodiversity of the ecosystem, reduce soil erosion, and promote the natural recovery of soil structure. In the sub-area in the second area used as ecotourism land, wetlands are constructed in surface subsidence areas with water bodies, and aquatic plants and / or microorganisms are placed in the water bodies in the surface subsidence areas to purify the water quality of the water bodies and restore the ecological functions of the water bodies.

[0063] The second area is further divided into sub-areas according to the construction purpose. The surface soil and water of each sub-area are treated accordingly according to the construction purpose, and the corresponding plant organisms are planted or released. The soil and water treatment ensures that the corresponding plant organisms can survive and grow, and a stable ecosystem is formed through a variety of plant organisms to achieve ecological restoration, while having high economic efficiency.

[0064] In some embodiments, the method for site construction of coal mine goaf areas of the embodiments of the present invention also includes a sub-area for implementing ecological buffering in the third area, implementing at least one of reinforced soil, soil solidification, ecological bags, ecological slope protection, artificial water replenishment, and artificial fertilization on the surface, planting shelterbelts and / or meadows to enhance the stability and resilience of the ecosystem, reduce soil erosion, and gradually improve soil structure and fertility. In the sub-area for implementing vegetation restoration in the third area, grouting is performed on the goaf, reinforced soil is implemented on the surface, and organic fertilizers and / or microbial agents are applied to the soil to improve soil stability and fertility, gradually restore the ecological functions of the subsidence area, and improve the ecological restoration effect. In the sub-area for implementing ecological protection and ecological restoration in the third area, reinforced soil is implemented on the surface, and micro-disturbance foundation treatment is performed on the corresponding buildings. The micro-disturbance foundation treatment includes shallow grouting and micro-piles, and vegetation restoration and / or wetland restoration are implemented to gradually restore the functions and structures of the damaged ecosystem and improve the stability and resilience of the ecosystem.

[0065] Furthermore, the sub-area for implementing ecological buffering is far away from the center of the subsidence area relative to the sub-area for implementing vegetation restoration. For example, the sub-area for implementing ecological buffering is located at the edge of the subsidence area or in the transition zone, and the sub-area for implementing vegetation restoration is located in an area where subsidence is severe but has tended to stabilize.

[0066] The third area is further divided into sub-areas according to ecological functions. Each sub-area implements corresponding treatment on the surface according to the ecological function to ensure the smooth implementation of the corresponding ecological function while having higher economic efficiency.

[0067] In some embodiments, the specific steps of implementing reinforced soil on the ground surface include removing debris from the ground surface and leveling the ground surface, the debris includes construction waste, stones, trees, grass roots, etc., the depth of debris removal is greater than or equal to 30 cm, and then rolling and compacting the ground surface. In the area with collapse and / or deformation cracks on the ground surface, a pit with a depth of 1.8m to 2.2m, preferably 2m, and a lateral size of at least 0.8m to 1.2m, preferably 1m is excavated, and then clay is used for layered compaction and backfilling to form a base with the ground surface, and the dry density of the base is greater than or equal to 1.4t / m 3. Multiple layers of clay are laid on the substrate to form a support layer, and each layer of clay is rolled and compacted after being laid, with a compaction degree greater than or equal to 0.96, a thickness of each layer of clay of 200 mm to 300 mm, and a moisture content of the clay of the optimal moisture content of this type of clay of ±2%. Medium-coarse sand is laid on the support layer to form a cushion layer, and the thickness of the cushion layer is 8 cm to 12 cm, preferably 10 cm. A bidirectional glass fiber geogrid is laid on the cushion layer, and the edge of the bidirectional glass fiber geogrid is located on the inner side of the edge of the support layer, and the distance between the edge of the bidirectional glass fiber geogrid and the edge of the support layer is greater than or equal to 2 m. Concrete is poured on the outer peripheral edge of the bidirectional glass fiber geogrid, and the length of the bidirectional glass fiber geogrid embedded in the concrete is 75 cm to 85 cm, preferably 80 cm. Clay is rammed on the bidirectional glass fiber geogrid to form a protective layer, and the thickness of the protective layer is 35 cm to 45 cm, preferably 40 cm.

[0068] The implementation of reinforced soil can significantly improve the strength and stability of the foundation and effectively prevent foundation settlement and deformation.

[0069] In some embodiments, the coal mine goaf site construction method of the embodiment of the present invention also includes setting physical monitoring sensors such as surface subsidence monitors, crack monitors, groundwater level monitors, etc. in the first area, the second area and the third area, as well as ecological monitoring sensors such as soil moisture sensors, soil nutrient sensors, biomass monitors, etc.

[0070] The first area, the second area and the third area after construction are monitored by physical monitoring sensors and ecological monitoring sensors.

[0071] In some embodiments, the method for constructing a coal mine goaf area in an embodiment of the present invention further includes: D The impact of construction on the goaf is divided into three levels: large, medium and small. D The impact of engineering construction on the goaf is great. D ≤H≤1.5H D The impact of engineering construction on the goaf is moderate, and when H>1.5H D The impact of engineering construction on the goaf is small. And / or according to the additional stress impact depth H a and the depth of the collapsed water-conducting fracture zone H lf The impact of engineering construction on the goaf is divided into three levels: large, medium and small. lf <H a The impact of engineering construction on the goaf is great. a ≤H lf <2.0H a The impact of engineering construction on the goaf is moderate. lf≥2.0H a The impact of engineering construction on the goaf is small.

[0072] According to the load critical influence depth H D and the depth of the goaf H, and the depth H affected by the additional stress a and the depth of the collapsed water-conducting fracture zone H lf By combining one or both of the above, the impact of engineering construction on goaf areas can be divided into three levels: large, medium and small, so as to classify the suitability of goaf areas according to the impact of engineering construction on goaf areas.

[0073] In some embodiments, the method for construction of a coal mine goaf area in an embodiment of the present invention further includes dividing the influence of the goaf area on the engineering construction into three levels: large, medium, and small according to the residual deformation value of the surface of the goaf area, wherein the residual deformation value of the surface includes a residual subsidence value W, a residual inclination value i, a residual horizontal deformation value ε, and a residual curvature value K. When W>200mm, i>10mm / m, ε>6mm / m, and K>0.6×10 -3 / m, the impact of the goaf on engineering construction is great. When 100mm≤W≤200mm, 3mm / m≤i≤10mm / m, 2mm / m≤ε≤6mm / m and 0.2×10 -3 / m≤ε≤0.6×10 -3 / m, the influence of goaf on engineering construction is moderate. When W < 100 mm, i < 3 mm / m, ε < 2 mm / m and K < 0.2 × 10 -3 / m, the impact of the goaf on the engineering construction is small. According to the goaf depth H and the goaf thickness M, the impact of the goaf on the engineering construction is divided into three levels: large, medium and small. When H < 50m or H / M < 30, the impact of the goaf on the engineering construction is large, when 50m≤H≤200m or 30≤H / M≤80, the impact of the goaf on the engineering construction is medium, and when H>200m or H / M>80, the impact of the goaf on the engineering construction is small; and according to the goaf site stability and engineering building deformation requirements, the impact of the goaf on the engineering construction is divided into three levels: large, medium and small. The engineering building deformation requirements include the absolute value of the horizontal deformation value |ε|, the absolute value of the inclination value |i| and the absolute value of the curvature value |K|. When the goaf site stability is stable, under the conditions of |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / m, the impact of the goaf on engineering construction is small. When the stability of the goaf is basically stable, the goaf will have a small impact on engineering construction if |ε|>6mm / m, |i|>10mm / m and |K|>0.6×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m<|K|≤0.6×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / m, the impact of the goaf on engineering construction is small. When the stability of the goaf is unstable, the goaf is unstable when |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m, the impact of the goaf on engineering construction is medium.

[0074] Among them, the surface residual deformation value of the goaf can be predicted based on the experience of construction personnel, can be replaced by the roughly similar surface residual deformation value of the goaf in the construction history, can also be predicted based on rock movement prediction systems such as MSPS, and a three-dimensional spatial model of the goaf can be established, combined with INSAR analysis and surface observation data to fit the surface collapse deformation for prediction.

[0075] According to the residual deformation value of the surface of the goaf, the depth H and thickness M of the goaf, the stability of the goaf site and the deformation requirements of the engineering building, or a combination of two or all three, the impact of the goaf on the engineering construction is divided into three levels: large, medium and small, and the suitability of the goaf site is divided according to the impact of the goaf on the engineering construction.

[0076] It can be understood that there is no restriction on the order of the step of classifying the impact of engineering construction on goaf into three levels: large, medium and small, and the step of classifying the impact of goaf on engineering construction into three levels: large, medium and small.

[0077] In other embodiments, the impact of the goaf on the engineering construction can be divided into three levels: large, medium and small according to the stability of the goaf site and the importance of the engineering buildings.

[0078] In some embodiments, the method for constructing a coal mine goaf area in an embodiment of the present invention further includes dividing the stability of the goaf area into three levels: stable, basically stable, and unstable according to the final mining time t of the goaf, and the stability of the goaf area is stable when t>1.2T and t>730d, and the stability of the goaf area is basically stable when 0.8T≤t≤1.2T and t>365d, and the stability of the goaf area is unstable when t<0.8T or t≤365d, where T is the duration of the surface movement, an integer number of days. According to the surface deformation characteristics, the stability of the goaf area is divided into three levels: stable, basically stable, and unstable, and the stability of the goaf area is stable when the surface is continuously deformed, in the middle area of ​​the basin, there are no ground cracks, no steps, and no collapse pits on the ground. The stability of the goaf area is basically stable when the surface is continuously deformed, in the edge area of ​​the basin, the ground is inclined and / or there are ground cracks, and the stability of the goaf area is unstable when the surface is discontinuously deformed, is a pumping type or a cutting type, and there are collapse pits or steps on the ground. According to the residual deformation value of the surface, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. -3 / m and W<100mm, the stability of the goaf is stable; when 3mm / m≤i≤6mm / m, 2mm / m≤ε≤4mm / m, 0.2×10 -3 / m≤ε≤0.4×10 -3 / m and 100mm≤W≤300mm, the stability of the goaf is basically stable. -3 / m and W>300mm, at least one of which is greater than 300mm; and according to the overburden type and the goaf depth ratio H / M, the goaf site stability is divided into three levels: stable, basically stable and unstable. When the overburden type is soft rock, the goaf site stability is stable when H / M>120, and is basically stable when 120≤H / M≤100, and is unstable when H / M<100. When the overburden type is medium-hard rock, the goaf site stability is stable when H / M>100, and is basically stable when 100≤H / M≤80, and is unstable when H / M<80. When the overburden type is hard rock, the goaf site stability is stable when H / M>80, and is basically stable when 80≤H / M≤60, and is unstable when H / M<60. At least one of .

[0079] Before the influence of goaf on engineering construction is divided into three levels: large, medium and small according to the stability of goaf site and deformation requirements of engineering buildings, it is necessary to obtain the stability level of goaf site. According to one or at least two of the four factors of goaf final mining time t, surface deformation characteristics, surface residual deformation value, overburden type and goaf depth ratio H / M, the stability of goaf site is divided into three levels: stable, basically stable and unstable. Therefore, the influence of goaf on engineering construction can be divided into three levels: large, medium and small according to the stability of goaf site and deformation requirements of engineering buildings.

[0080] It is understandable that in the process of classifying the impact of goaf on engineering construction into three levels: large, medium and small, if the goaf site stability is not applied, there is no need to implement the step of classifying the goaf site stability.

[0081] In some embodiments, the method for construction of coal mine goaf area in the embodiment of the present invention further includes, before the influence degree of engineering construction on the goaf area is divided into three levels: large, medium and small, the influence degree of the goaf area on the engineering construction is divided into three levels: large, medium and small, and the influence degree of the goaf area on the engineering construction is divided into three levels: large, medium and small, and the influence degree of the goaf area on the engineering construction is divided into three levels: large, medium and small, D , goaf depth H, additional stress influence depth H a , Depth of collapsed water-conducting fracture zone H lf , surface residual deformation value, goaf thickness M, goaf final mining time t and surface deformation characteristics.

[0082] Specifically, the survey methods include remote sensing interpretation, transient electromagnetic method, controlled source audio magnetotelluric method, high-density resistivity method, geophysical well logging method, in-hole videography, indoor rock and soil testing, etc., and then draw the plane distribution map of goaf collapse and geological profile map, establish a three-dimensional surface model, and establish a three-dimensional BIM geological model of geological drilling to construct the rock and soil body and goaf area distribution for analysis and simulation.

[0083] In the description of the present invention, it should be understood that the terms "first" and "second" are only used for distinction, and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0084] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0085] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for construction of a coal mine goaf area, characterized in that: include: According to the influence of goaf on engineering construction and the influence of engineering construction on goaf, the suitability of goaf site is divided into three levels: suitable, basically suitable and poor suitability. Among them, the suitable level includes the influence of goaf on engineering construction is small and the influence of engineering construction on goaf is small. The basically suitable level includes the influence of goaf on engineering construction is medium and the influence of engineering construction on goaf is medium. The poor suitability level includes the influence of goaf on engineering construction is large and the influence of engineering construction on goaf is large. The first area of ​​the goaf site corresponding to the suitability level is used for constructing at least one of industrial buildings, commercial buildings, public facilities, high-rise residential buildings, and infrastructure; The second area of ​​the goaf site corresponding to the basic suitability level is used as at least one of agricultural land, forestry land, and eco-tourism land; The third area of ​​the goaf site corresponding to the poor suitability level is used to implement at least one of ecological buffering, vegetation restoration, ecological protection, and ecological restoration.

2. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: The goaf of the sub-area in the first area for constructing industrial buildings and commercial buildings is filled by at least one of high-pressure grouting, penetration grouting, segmented grouting, layered grouting and intermittent grouting; The goaf of the sub-area in the first area for the construction of public facilities and high-rise residential buildings is filled with fine grouting; The goaf of the sub-area in the first area for infrastructure construction is filled by high pressure grouting or infiltration grouting.

3. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: In the sub-area of ​​the first area for constructing industrial buildings and commercial buildings, at least one of pile foundation, raft foundation and underground continuous wall is provided for the corresponding buildings; In the sub-area of ​​the first area for constructing public facilities and high-rise residential buildings, at least one of a settlement joint, a sliding bearing, a seismic isolation device, a protective wall, an isolation belt, a prestressed anchor rod, and an underground continuous wall is provided corresponding to the building; In the first area, a sub-area corresponding to a building for constructing infrastructure is provided with detection equipment to detect the grouting area.

4. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: In the sub-area of ​​the second area used as agricultural land and forestry land, grouting is performed on the mined-out area, and soil reinforcement and / or ground compaction are performed on the surface; In the sub-area of ​​the second area used as eco-tourism land, grouting filling is performed on the goaf, and pile foundation treatment and / or foundation reinforcement is implemented on the surface subsidence area.

5. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: In the sub-area of ​​the second area used as agricultural land and forestry land, at least one of organic matter, trace elements and soil conditioners is applied to the soil, and at least one of drought-tolerant crops, nitrogen-fixing plants and pioneer tree species is planted; In the sub-area of ​​the second area used as ecotourism land, wetlands are constructed in the surface subsidence area with water bodies, and aquatic plants and / or microorganisms are released into the water bodies in the surface subsidence area.

6. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: In the sub-area of ​​the third area for implementing ecological buffer, at least one of reinforced soil, soil solidification, ecological bags, ecological slope protection, artificial water replenishment, and artificial fertilization is implemented on the surface, and protective forests and / or meadows are planted; In the sub-area of ​​the third area for implementing vegetation restoration, grouting is performed on the goaf, soil reinforcement is performed on the surface, and organic fertilizers and / or microbial agents are applied to the soil; In the sub-area of ​​the third area used for implementing ecological protection and ecological restoration, reinforced soil is implemented on the surface, micro-disturbance foundation treatment is performed on the corresponding buildings, and vegetation restoration and / or wetland restoration is implemented.

7. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: Physical monitoring sensors and ecological monitoring sensors are set in the first area, the second area and the third area.

8. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: According to the load critical influence depth H D The impact of construction on the goaf is divided into three levels: large, medium and small. D The impact of engineering construction on the goaf is great. D ≤H≤1.5H D The impact of engineering construction on the goaf is moderate, and when H>1.5H D The impact of construction on the goaf is small; and / or According to the additional stress influence depth H a and the depth of the collapsed water-conducting fracture zone H lf The impact of engineering construction on the goaf is divided into three levels: large, medium and small. lf <H a The impact of engineering construction on the goaf is great. a ≤H lf <2.0H a The impact of engineering construction on the goaf is moderate. lf ≥2.0H a The impact of engineering construction on the goaf is small.

9. The method for construction of coal mine goaf area according to claim 1, characterized in that: Also includes: The influence of goaf on engineering construction is divided into three levels: large, medium and small according to the residual deformation value of the surface of the goaf. The residual deformation value of the surface includes the residual subsidence value W, the residual inclination value i, the residual horizontal deformation value ε and the residual curvature value K. When W>200mm, i>10mm / m, ε>6mm / m and K>0.6×10 -3 / m, the impact of the goaf on engineering construction is great. When 100mm≤W≤200mm, 3mm / m≤i≤10mm / m, 2mm / m≤ε≤6mm / m and 0.2×10 -3 / m≤ε≤0.6×10 -3 / m, the influence of goaf on engineering construction is moderate. When W < 100 mm, i < 3 mm / m, ε < 2 mm / m and K < 0.2 × 10 -3 / m When the goaf has little impact on engineering construction; According to the goaf depth H and goaf thickness M, the impact of the goaf on engineering construction is divided into three levels: large, medium and small. When H < 50m or H / M < 30, the impact of the goaf on engineering construction is large; when 50m ≤ H ≤ 200m or 30 ≤ H / M ≤ 80, the impact of the goaf on engineering construction is medium; when H > 200m or H / M > 80, the impact of the goaf on engineering construction is small; and The influence of goaf on engineering construction is divided into three levels: large, medium and small according to the stability of goaf site and the deformation requirements of engineering buildings. The deformation requirements of engineering buildings include the absolute value of horizontal deformation value |ε|, the absolute value of inclination value |i| and the absolute value of curvature value |K|. When the stability of the goaf is stable, under the conditions of |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / mWhen at least one of the above conditions is met, the impact of the goaf on engineering construction is small. When the stability of the goaf is basically stable, the stability of the goaf is basically stable when |ε|>6mm / m, |i|>10mm / m and |K|>0.6×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m<|K|≤0.6×10 -3 / m, the impact of the goaf on engineering construction is moderate. -3 / mWhen at least one of the above conditions is met, the impact of the goaf on engineering construction is small. When the stability of the goaf is unstable, the stability of the goaf is unstable when |ε|>4mm / m, |i|>6mm / m and |K|>0.4×10 -3 / m, the goaf has a great impact on engineering construction. -3 / m, when at least one of the above is true, the impact of the goaf on the engineering construction is moderate; At least one of .

10. The method for construction of coal mine goaf area according to claim 9, characterized in that: Also includes: According to the final mining time t of the goaf, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. When t>1.2T and t>730d, the stability of the goaf site is stable; when 0.8T≤t≤1.2T and t>365d, the stability of the goaf site is basically stable; when t<0.8T or t≤365d, the stability of the goaf site is unstable, where T is the duration of surface movement, which is an integer number of days; According to the surface deformation characteristics, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. The goaf site stability is stable when the surface is continuously deformed, located in the middle area of ​​the basin, without ground fissures, steps and collapse pits. The goaf site stability is basically stable when the surface is continuously deformed, located in the edge of the basin, with ground tilt and / or ground fissures. The goaf site stability is unstable when the surface is discontinuously deformed, of the pumping or cutting type, with collapse pits or steps on the ground. According to the residual deformation value of the surface, the stability of the goaf site is divided into three levels: stable, basically stable and unstable. -3 / m and W<100mm, the stability of the goaf is stable; when 3mm / m≤i≤6mm / m, 2mm / m≤ε≤4mm / m, 0.2×10 -3 / m≤ε≤0.4×10 -3 / m and 100mm≤W≤300mm, the stability of the goaf is basically stable. -3 / m and W>300mm, at least one of them is considered unstable; and According to the overburden type and goaf depth ratio H / M, the goaf site stability is divided into three levels: stable, basically stable and unstable. When the overburden type is weak rock, the stability of the goaf is stable when H / M>120, the stability of the goaf is basically stable when 120≤H / M≤100, and the stability of the goaf is unstable when H / M<100. When the overburden type is medium hard rock, the stability of the goaf is stable when H / M>100, the stability of the goaf is basically stable when 100≤H / M≤80, and the stability of the goaf is unstable when H / M<80. When the overburden type is hard rock, the stability of the goaf is stable when H / M>80, basically stable when 80≤H / M≤60, and unstable when H / M<60; At least one of .