CN105257293A - Method for mining pressed coal below shallow buried gas delivery pipelines - Google Patents

Abstract

The invention discloses a method for mining pressed coal below shallow buried gas delivery pipelines. The method includes steps of (1), establishing earth surface subsidence curve equations W and predicting subsidence conditions of earth surfaces along the directions of the pipelines after resources are mined; (2), computing bending moment of the shallow buried gas delivery pipelines and the maximum bending stress of the pipelines; (3), determining required-to-be-protected ranges of the shallow buried gas delivery pipelines; (4), erecting suspension bridges along the directions of the pipelines according to the protected ranges determined at the step 3 and lifting the pipelines in subsidence areas; (5), mining the coal resources below the pipelines in conventional modes, detaching the suspension bridges after the earth surfaces are subsided and then are stable, and repeatedly carrying out the steps before a next working face is mined until all the resources in a mining area are completely mined. The method has the advantages that the shallow buried gas delivery pipelines can be protected by a process for suspending the pipelines by the aid of the suspension bridges according to dynamic deformation influence on the shallow buried gas delivery pipelines when the coal resources are mined, and accordingly the pressed coal resources below the pipelines can be mined in the normal mining modes.

Description

A kind of shallow embedding ground gas transmission line presses down the exploitation method of coal

Technical field

The present invention relates to a kind of exploitation method of pressing coal, specifically a kind of shallow embedding ground gas transmission line presses down the exploitation method of coal, belongs to field of coal mining.

Background technology

The subsidence that coal mining brings out can cause great destruction to ground surface environment and structure.China head's Distance Gas Transmission Pipeline has passed through China's Main Coalfields distributed area, and along with the continuous enlargement of Coal Mining Area area, increasing gas transmission line will be adopted depression to be affected.Pipeline inner high voltage gas is inflammable, explosive, once generation Leakage Gas or line break very easily cause major accident, causes great casualties and property loss, makes social production and national economy suffer serious harm.

Existing gas transmission line major part is shallow embedding ground gas transmission line, and its guard method mainly adopts to stay establishes protection coal pillar.The method is in process of coal mining, according to shallow embedding ground gas transmission line and seam contrast, estimates pipeline protection coal column scope, stays and establish protection coal pillar not exploit, and makes shallow embedding ground gas transmission line not by the impact of Sbusidence Damage.Mainly there is following shortcoming in the method:

(1) layout of shallow embedding ground gas transmission line relative coal mining work plane has randomness, and the pipeline protection coal column in coal mining makes a big impact to the layout of coal mining work plane and colliery, mining area expanding design.

(2) protection coal pillar that shallow embedding ground gas transmission line is along the line is usually wider, and generally the width of protection coal pillar is all at about 1000m, and this will cause the waste of a large amount of coal resources.

(3) holding up of shallow embedding ground gas transmission line coal resources along the line brings tremendous influence by the production in mining area and economic benefit, affects the sustainable development in mining area.

Summary of the invention

The object of the present invention is to provide a kind of shallow embedding ground gas transmission line to press down the exploitation method of coal, the method can either available protecting gas transmission line, can press down coal by high efficiency exploitation pipeline again.

For achieving the above object, a kind of shallow embedding ground gas transmission line presses down the exploitation method of coal, comprises the following steps:

A. according to terrene shift observing data determination shallow embedding ground gas transmission line movements and deformations parameter after other Regional Coal resource recoveries of mining area, adopt probability integration process to set up surface subsidence curvilinear equation W, after prediction resource exploitation, earth's surface is along pipeline direction sinking situation;

B. buried pipeline moment of flexure and maximum stress in bend is calculated according to above-mentioned surface subsidence curvilinear equation

Can obtain buried pipeline calculation of Bending Moment equation according to the bending theory of continuous beam is:

$M\left(l\right)=EI\frac{d^{2}W}{{\mathrm{dl}}^2}$

In formula, E is the tensile modulus of elasticity of pipeline, and I is pipe cross-sectional moment of inertia,

Pipeline maximum stress in bend is:

$\mathrm{\σ}\left(l\right)=\frac{M\left(l\right)d}{I}$

In formula, d is the radius of pipe cross-sectional;

C. determine shallow buried pipeline axial tension stress according to maximum stress in bend, need the scope of protection in conjunction with pipeline allowable tensile stress determination shallow embedding ground gas transmission line

In Subsidence Area, the design formulas of buried pipeline axial tension stress along the line is:

σ _n(l)＝σ _n0+σ(l)

σ in formula _n ⁰for the initial axial tension stress of pipeline, can obtain according to pressure and duty in pipeline, pipeline allowable tensile stress is [σ], works as σ _nl, during ()>=[σ], the axial tension stress of correspondence position pipeline has exceeded allowable tensile stress, determine that buried pipeline needs to take the scope of safeguard measure thus; Work as σ _nl, time () < [σ], the axial tension stress of correspondence position pipeline is less than allowable tensile stress, pipeline does not need to arrange safeguard measure herein;

D. the protection domain determined according to step c along pipeline direction erecting suspension bridge, Subsidence Area pipeline of slinging;

E. exploit pipeline in a usual manner and press down coal resources, until this work plane resource recovery is complete;

F. after above-mentioned work plane subsidence is stable, suspension bridge is removed; Repeat step a to step e, complete the work of next work plane exploitation of coal resources; So cut coal resource continuously, until all working face resource exploitation in this exploiting field is complete.

The present invention can affect the dynamic deformation that shallow embedding gas transmission ground pipeline produces according to during exploitation of coal resources, adopts suspension bridge overhead pipe to protect shallow embedding ground gas transmission line, thus the coal resources held up under adopting conventional mining type can exploit out pipeline.Suspension bridge erection is simple, and critical piece can reuse; After subsidence is stable, suspension bridge removes, because pipeline self has certain tensile properties, there will be no burst distortion, generally without the need to support of banketing, operation is comparatively simple; The expense that erecting suspension bridge increases, less than 1% of whole cost of production, but by the flood tide mining pressed coal under pipeline out, can have high economic benefit.

Accompanying drawing explanation

Fig. 1 is the schematic diagram of specific embodiments of the invention;

Fig. 2 is the schematic diagram of supporting seat in the present invention;

In figure: 1, support pier, 2, suspention cable wire, 3, support pier basis, 4, pipeline, 5, hoist cable, 6, pipeline support seat, 61, collet, 62, upper cover, 63, groove, 64, bolt, 65, hanger.

Detailed description of the invention

Below in conjunction with accompanying drawing, the invention will be further described.

Shallow embedding ground gas transmission line presses down an exploitation method for coal, comprises the following steps:

A. according to terrene shift observing data determination shallow embedding ground gas transmission line movements and deformations parameter after other Regional Coal resource recoveries of mining area, adopt probability integration process to set up surface subsidence curvilinear equation W, after prediction resource exploitation, earth's surface is along pipeline direction sinking situation;

B. buried pipeline moment of flexure and maximum stress in bend is calculated according to above-mentioned surface subsidence curvilinear equation

Can obtain buried pipeline calculation of Bending Moment equation according to the bending theory of continuous beam is:

$M\left(l\right)=EI\frac{d^{2}W}{{\mathrm{dl}}^2}$

In formula, E is the tensile modulus of elasticity of pipeline, and I is pipe cross-sectional moment of inertia,

Pipeline maximum stress in bend is:

$\mathrm{\&sigma;}\left(l\right)=\frac{M\left(l\right)d}{I}$

In formula, d is the radius of pipe cross-sectional;

C. determine shallow buried pipeline axial tension stress according to maximum stress in bend, need the scope of protection in conjunction with pipeline allowable tensile stress determination shallow embedding ground gas transmission line

In Subsidence Area, the design formulas of buried pipeline axial tension stress along the line is:

σ _n(l)＝σ _n0+σ(l)

σ in formula _n0 is the initial axial tension stress of pipeline, and can obtain according to pressure and duty in pipeline, pipeline allowable tensile stress is [σ], works as σ _nl, during ()>=[σ], the axial tension stress of correspondence position pipeline has exceeded allowable tensile stress, determine that buried pipeline needs to take the scope of safeguard measure thus; Work as σ _nl, time () < [σ], the axial tension stress of correspondence position pipeline is less than allowable tensile stress, pipeline does not need to arrange safeguard measure herein;

D. the protection domain determined according to step c along pipeline direction erecting suspension bridge, Subsidence Area pipeline of slinging;

E. exploit pipeline in a usual manner and press down coal resources, until this work plane resource recovery is complete;

F. after above-mentioned work plane subsidence is stable, suspension bridge is removed; Repeat step a to step e, complete the work of next work plane exploitation of coal resources; So cut coal resource continuously, until all working face resource exploitation in this exploiting field is complete.

The present invention can affect the dynamic deformation that shallow embedding gas transmission ground pipeline produces according to during exploitation of coal resources, adopts suspension bridge overhead pipe to protect shallow embedding ground gas transmission line, thus the coal resources held up under adopting conventional mining type can exploit out pipeline.Suspension bridge erection is simple, and critical piece can reuse; After subsidence is stable, suspension bridge removes, because pipeline self has certain tensile properties, there will be no burst distortion, generally without the need to support of banketing, operation is comparatively simple; The expense that erecting suspension bridge increases, less than 1% of whole cost of production, but by the flood tide mining pressed coal under pipeline out, can have high economic benefit.

In described step a, surface movements and deformation preferred parameter comprises: subsidence factor, displacement factor, deviation of inflection point, seam mining affect angle, the modulus of elasticity of rock mass and intensity, and these preferred parameters can reflect Subsidence Area ground shift and deformation situation comprehensively.

The preferred embodiment that Fig. 1 is suspension bridge described in steps d; comprise support pier 1 and suspention cable wire 2; described support pier 1 is arranged on the two ends that gas transmission line 4 needs protection zone; support pier basis 3 is provided with below it; support pier basis 3 is arranged in gas transmission line 4 bilateral symmetry; gas transmission line 4 passes between two support pier bases 3, and suspention cable wire 2 is erected between two support piers 1, and hoist cable 5 is suspended on suspention cable wire 2.Described support pier 1 adopts cement structures, and this suspension bridge cost is low.

Further, gas transmission line 4 is sling by supporting seat 6 by hoist cable 5, and supporting seat 6 can available protecting gas transmission line 4.

Fig. 2 is a preferred version of supporting seat 6, comprises collet 61 and upper cover 62, and described collet 61 and upper cover 62 are arranged respectively the groove 63 for settling pipeline, collet 61 is connected by bolt 64 with upper cover 62, and upper cover 62 arranges hanger 65; Gas transmission line 4 of slinging like this is not only convenient but also firm.Also can without upper cover, base top edge directly arranges some hangers, needs the hoist cable of respective numbers like this.

Claims (5)

1. shallow embedding ground gas transmission line presses down an exploitation method for coal, it is characterized in that, comprises the following steps:

A. according to terrene shift observing data determination shallow embedding ground gas transmission line movements and deformations parameter after other Regional Coal resource recoveries of mining area, adopt probability integration process to set up surface subsidence curvilinear equation W, after prediction resource exploitation, earth's surface is along pipeline direction sinking situation;

B. buried pipeline moment of flexure and maximum stress in bend is calculated according to above-mentioned surface subsidence curvilinear equation

Can obtain buried pipeline calculation of Bending Moment equation according to the bending theory of continuous beam is:

$M\left(l\right)=EI\frac{d^{2}W}{{\mathrm{dl}}^2}$

In formula, E is the tensile modulus of elasticity of pipeline, and I is pipe cross-sectional moment of inertia,

Pipeline maximum stress in bend is:

$\mathrm{\&sigma;}\left(l\right)=\frac{M\left(l\right)d}{I}$

In formula, d is the radius of pipe cross-sectional;

C. determine shallow buried pipeline axial tension stress according to maximum stress in bend, need the scope of protection in conjunction with pipeline allowable tensile stress determination shallow embedding ground gas transmission line

In Subsidence Area, the design formulas of buried pipeline axial tension stress along the line is:

σ _n(l)＝σ _n0+σ(l)

σ in formula _n0for the initial axial tension stress of pipeline, can obtain according to pressure and duty in pipeline, pipeline allowable tensile stress is [σ], works as σ _nl, during ()>=[σ], the axial tension stress of correspondence position pipeline has exceeded allowable tensile stress, determine that buried pipeline needs to take the scope of safeguard measure thus; Work as σ _nl, time () < [σ], the axial tension stress of correspondence position pipeline is less than allowable tensile stress, pipeline does not need to arrange safeguard measure herein;

D. the protection domain determined according to step c along pipeline direction erecting suspension bridge, Subsidence Area pipeline of slinging;

E. the pressure coal under pipeline is exploited in a usual manner, until this work plane resource recovery is complete;

F. after above-mentioned work plane subsidence is stable, suspension bridge is removed; Repeat step a to step e, complete the work of next work plane exploitation of coal resources; So cut coal resource continuously, until all working face resource exploitation in this exploiting field is complete.

2. shallow embedding ground according to claim 1 gas transmission line presses down the exploitation method of coal, it is characterized in that, in described step a, surface movements and deformation preferred parameter is: subsidence factor, displacement factor, deviation of inflection point, seam mining affect angle, the modulus of elasticity of rock mass and intensity.

3. shallow embedding ground according to claim 2 gas transmission line presses down the exploitation method of coal, it is characterized in that, described steps d centre suspension cord bridge comprises support pier (1) and suspention cable wire (2), described support pier (1) is arranged on the two ends, region that gas transmission line (4) needs protection, support pier basis (3) is provided with below it, support pier basis (3) is arranged in gas transmission line (4) bilateral symmetry, and gas transmission line (4) passes between two support pier bases (3); Suspention cable wire (2) is erected between two support piers (1), and pipeline (4) is suspended in suspention cable wire (2) by hoist cable (5).

4. shallow embedding ground according to claim 3 gas transmission line presses down the exploitation method of coal, and it is characterized in that, gas transmission line (4) is sling by supporting seat (6) by hoist cable (5).

5. shallow embedding ground according to claim 4 gas transmission line presses down the exploitation method of coal, it is characterized in that, described pipeline support seat (6) comprises collet (61) and upper cover (62), described collet (61) and upper cover (62) are arranged respectively the groove (63) for settling gas transmission line (4), collet (61) is connected by bolt (64) with upper cover (62), and upper cover (62) arranges hanger (65).