CN106194185A - Under hydraulic pressure effect, thick aqueous soil layer sand control coal and rock pillar for safety stays equipment, method - Google Patents
Under hydraulic pressure effect, thick aqueous soil layer sand control coal and rock pillar for safety stays equipment, method Download PDFInfo
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- CN106194185A CN106194185A CN201610438364.7A CN201610438364A CN106194185A CN 106194185 A CN106194185 A CN 106194185A CN 201610438364 A CN201610438364 A CN 201610438364A CN 106194185 A CN106194185 A CN 106194185A
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21C—MINING OR QUARRYING
- E21C41/00—Methods of underground or surface mining; Layouts therefor
- E21C41/16—Methods of underground mining; Layouts therefor
- E21C41/18—Methods of underground mining; Layouts therefor for brown or hard coal
Abstract
What the present invention disclosed thick aqueous soil layer sand control coal and rock pillar for safety under a kind of hydraulic pressure effect stays equipment, method, comprising: treat the argillic horizon below working seam overlying thick aqueous soil layer to carry out liquid-limit & plastic-limit test, the bedrock weathering zone rock being pointed to side, water-bearing layer is dried saturated water absorption test and slaking test；The liquid of argillic horizon, plasticity index and the dry saturated water absorption of bedrock weathering zone rock, the disintegrating property parameter obtained according to test, determines whether loose aquifer is positioned in sealing water conservation laminated structure；If being positioned in sealing water conservation laminated structure, it is determined that the thickness H of sand control coal and rock pillar for safety under hydraulic pressure effectsp, and by this thickness the sand control coal and rock pillar for safety treating working seam under thick aqueous soil layer under hydraulic pressure effect stayed and set.Using the inventive method to exploit, can reduce colliery and burst the Probability of sand disaster accident, the inventive method is supplemented and perfect China's coal mining under water bodies sand control coal and rock pillar for safety stays the theory of equipment, method, has the highest practical value.
Description
Technical field
The present invention relates to Mineral Engineering field, particularly relate to the safe coal petrography of thick aqueous soil layer sand control under a kind of hydraulic pressure effect
Post stay equipment, method.
Background technology
In recent years, owing to coal resources are petered out, many mining areas on the ground such as East China, North China, will for improving mining up per limit
Under thick aqueous soil layer, superficial part seam mining is as the vital task of mine, i.e. loose seam's thickness is not less than 100m, and water-bearing layer is former
Beginning hydraulic pressure is not in little 1MPa.Although China has carried out substantial amounts of research in terms of mining under water bodies, have accumulated abundant practice warp
Test, but the factors such as the degree of the degree of water-rich of the difference of different regions hydrogeologic condition, unconsolidated formation and raising mining up per limit,
China being exploited under the special geologic condition such as thick aqueous soil layer, thin bedrock and yet suffers from series of problems, gushing water is burst sand
Accident happens occasionally, and the safety in production in colliery in serious threat.The safe working of thick aqueous soil layer also becomes a tackling key problem difficulty
Topic.
Existing achievement in research focuses mostly at Moderate and Thick Unconsolidated Formation bottom aquifer and basement rock bump contact, and shallow overburden,
In the case of pore water pressure is little, document " coal mining mechanism of water inrush and study on prevention under unconsolidated confined aquifer " (mining and safety
Engineering journal, 2011,28 (3): 333-339) and Ph.D. Dissertation " under high hydraulic pressure loose aquifer, coal mining key stratum is compound broken
Disconnected cause calamity Mechanism Study " use the mechanism of water gush face under the technique study medium watery of thick loose layer of sand of analog simulation
And countermeasure, and the prophylactico-therapeutic measuress such as top board presplit blasting, Water level fall quickly early warning, fltting speed regulation and control are proposed.But this prophylactico-therapeutic measures is also
Thick aqueous soil layer waterproof safety coal petrography post under hydraulic pressure effect is not stayed and set proposition and stay equipment, method, and be not directed to thick loose
Under the layer weak watery of layer of sand, sand control coal and rock pillar for safety stays equipment, method.
According to the experience with mining of conventional thin bedrock, if having thicker clay below aquifer sand layer and forming Di Nian district, then thick
The resistance water isolating of clay makes work surface be capable of safe working；If it is bigger that aquifer sand layer forms area in the bottom of unconsolidated formation
Gravel Fu Cun district, then the exploitation adjacent to work surface can feed through to aquifer sand layer so that the water level of aquifer sand layer is decreased without
Keep higher hydraulic pressure, also can realize safe working.Wherein, thin bedrock refers to that bedrock thickness is more than caving zone height and is less than water guide
Slit band height.Along with Moderate and Thick Unconsolidated Formation bottom aquifer mining areas such as Juye, Shandong, Henan Zhao Gu, Northern Huaihe River Anhui, Jiangsu great Tun
Exploitation, according to " building, water body, railway and main roadway coal column stay and set and mining pressed coal code " (version in 2000) weak watery
Aquifer sand layer stays sand coal and rock pillar for safety of setting up defences, the coal-face in part mining area still to there occurs routed sand accident, and problems
It is on the increase, illustrates that the equipment, method that stays in code the most can not adapt to Moderate and Thick Unconsolidated Formation sand control safety coal completely
Staying of rock pillar sets requirement.
Summary of the invention
The purpose of the present invention is contemplated to solve the problems referred to above, it is provided that thick aqueous soil layer sand control peace under a kind of hydraulic pressure effect
Full coal petrography post stay equipment, method, under hydraulic pressure effect, increase staying of sand control coal and rock pillar for safety set thickness, it is possible to reduce burst sand in colliery
The Probability of disaster accident, and, the method for the present invention is supplementary and perfect, and China's sand control coal and rock pillar for safety stays equipment, method
Theory, has the highest practical value.
For realizing the above-mentioned purpose of the present invention, the present invention provides thick aqueous soil layer sand control safety coal under a kind of hydraulic pressure effect
Rock pillar stay equipment, method, comprising:
For treating the geological conditions of working seam overlying thick aqueous soil layer, it is pointed to the argillic horizon below water-bearing layer and carries out
Liquid-limit & plastic-limit test, in order to obtain the liquid of argillic horizon, plasticity index；
The bedrock weathering zone rock being pointed to side, described water-bearing layer is dried saturated water absorption test and slaking test,
To obtain dry saturated water absorption and the disintegrating property parameter of bedrock weathering zone rock；
According to the liquid of argillic horizon obtained, plasticity index and the dry saturated water absorption of bedrock weathering zone rock, disintegrative
Energy parameter, determines whether thick aqueous soil layer is positioned in sealing water conservation laminated structure；
If thick aqueous soil layer is positioned in sealing water conservation laminated structure, it is determined that the hydraulic pressure corresponding with sealing water conservation laminated structure
The thickness H of the lower sand control coal and rock pillar for safety of effectsp；
According to the thickness H of sand control coal and rock pillar for safety under the hydraulic pressure effect determinedsp, treat the safe coal petrography of sand control of working seam
Post carries out staying setting.
Wherein it is determined that the thickness H of sand control coal and rock pillar for safety under hydraulic pressure effectspBefore, the coal column under hydraulic pressure effect need to be determined
Lesion thickness Hp。
Wherein, the coal petrography post lesion thickness H under described hydraulic pressure effectpDetermination be by bedrock weathering zone rock is carried out
The method of strength test.
Wherein, by described bedrock weathering zone rock is made a strength test so that the coal column determined under hydraulic pressure effect damages
Hinder thickness Hp, comprise the steps:
The described bedrock weathering zone rock of different depth is carried out point load strength test, in order to obtain the base of different depth
The intensity data of rock weathered zone rock；
The intensity data obtained is processed, in order to obtain the standard point load of the bedrock weathering zone rock of different depth
Intensity data；
According to the standard point load intensity data obtained, by described basement rock corresponding when being zero with standard point load intensity
The degree of depth of weathered zone rock is defined as coal column lesion thickness Hp。
Wherein it is determined that the coal petrography post lesion thickness H under hydraulic pressure effectpBefore, also include bedrock weathering zone mud class rock is carried out
Mining induced fissure expanding test under hydraulic pressure effect, in order to determine that the resistance grittiness of weathered zone mud class rock protective layer can be under hydraulic pressure effect
No lose.
Wherein, the thickness H of sand control coal and rock pillar for safety under described hydraulic pressure effectspEqual to caving zone maximum height Hm, protective layer
Thickness HbWith coal column lesion thickness HpSum.
Wherein, if described thick aqueous soil layer is not located at sealing in water conservation laminated structure, it is determined that with non-tight water conservation pressure knot
The thickness H of the sand control coal and rock pillar for safety that structure is correspondings。
Wherein, the thickness H of the described sand control coal and rock pillar for safety corresponding with non-tight water conservation laminated structuresEqual to caving zone
Big height HmWith protective layer thickness HbSum.
Preferably, treat described in that working seam overlying thick aqueous soil layer is wedge structure.
Wherein, according to the liquid of argillic horizon obtained, the dry saturated water absorption of plasticity index and bedrock weathering zone rock, collapse
Solve performance parameter, in determining under hydraulic pressure effect, whether loose aquifer is positioned at sealing water conservation laminated structure, including:
If the plasticity index of described argillic horizon more than 17, liquidity index is less than 0.25, it is determined that described argillic horizon has good
Good water-resisting property and the plasticity of difference；
It is dried the rock that saturated water absorption is more than 15% or slake-durability is poor if described bedrock weathering zone rock exists,
Then determine that described bedrock weathering zone rock has good water-resisting property；
If described argillic horizon and described bedrock weathering zone rock have good water-resisting property, it is determined that described thick loose is aqueous
Layer is positioned in sealing water conservation laminated structure；Otherwise, it is determined that the easy Draining hook of described thick aqueous soil layer.
Compared with prior art, under the hydraulic pressure effect of the present invention thick aqueous soil layer sand control coal and rock pillar for safety stay equipment, method
Have the advantage that
1, in the method for the present invention, be proposed for loose aquifer under hydraulic pressure effect be positioned at sealing pressure-maintaining structure in time, need
Determine the thickness H of sand control coal and rock pillar for safety under the hydraulic pressure effect corresponding with thick aqueous soil layer under hydraulic pressure effectsp, and according to being somebody's turn to do
Thickness is operated the exploitation in face, such that it is able to there is the probability of routed sand accident during exploitation reducig, is beneficial to safety in production；
2, in the method for the present invention, Point Loading Strength Test is utilized to determine the coal column lesion thickness H under hydraulic pressurep, and accordingly
Calculate the thickness H of sand control coal and rock pillar for safety under hydraulic pressure effectsp, supplement and perfect China's coal mining under water bodies sand control coal and rock pillar for safety
Stay the theory of equipment, method, there is the highest practical value.
The present invention is described in detail below in conjunction with the accompanying drawings.
Accompanying drawing explanation
Fig. 1 is that the staying of loose aquifer sand control coal and rock pillar for safety of prior art sets figure；
Fig. 2 be the present invention hydraulic pressure effect under staying of thick aqueous soil layer sand control coal and rock pillar for safety set figure；
Fig. 3 is the wedge-type seal pressure-maintaining structure geological model figure of the thick aqueous soil layer of the method being suitable for the present invention；
Fig. 4 be the present invention hydraulic pressure effect under the flow chart staying equipment, method of thick aqueous soil layer sand control coal and rock pillar for safety；
Fig. 5 is that the rock fracture retention of excessive fluid that the present invention uses is burst the structural representation of sand expanding test device；
Fig. 6 is that weathered zone rock is dried the saturated water absorption Changing Pattern figure with the degree of depth；
Aluminum matter mud stone disintegrate state diagram after 30 minutes when Fig. 7 is disaggregation；
Sandy Silt disintegrate state diagram after 24 hours when Fig. 8 is disaggregation；
Sandstone disintegrate state diagram after 24 hours when Fig. 9 is disaggregation；
Figure 10 is the weathered zone rock point load intensity Changing Pattern figure with the degree of depth；
Water pressure versus time curve figure when Figure 11 is weathered zone rock mining induced fissure expanding test；
Figure 12 is to test forward and backward test specimen state diagram during weathered zone rock mining induced fissure expanding test；
Detailed description of the invention
The thick loose treating working seam overlying wedge shaped sealing structure that the method for the present invention is applicable to as shown in Figure 3 is aqueous
The geological conditions of layer.
Wherein, the geological conditions of the thick aqueous soil layer of overlying wedge shaped sealing structure, refer to work surface overlying thick loose
The upper and lower thick-bedded clay of layer bottom aquifer forms wedge-type seal structure as shown in Figure 3 with bedrock weathering zone.If water-bearing layer
Upper and lower thick-bedded clay is good with the water isolating of bedrock weathering zone rock, then water-bearing layer can keep relatively Gao Shui under air-proof condition
Press, and the exploitation of neighbouring work surface fails to dredge the water level dropping this water-bearing layer.
And in prior art, when the geological conditions of the thick aqueous soil layer having as shown in Figure 3 is exploited, to anti-
The staying to set still to carry out staying according to the method for existing code of sand coal and rock pillar for safety thickness sets (as shown in Figure 1), i.e. sand control safety coal
The thickness H of rock pillarsEqual to caving zone maximum height HmWith protective layer thickness HbSum.
At the thickness H staying the sand control coal and rock pillar for safety set with prior artsGeology to coal seam overlying thick aqueous soil layer
When condition is exploited, still occur in that to burst sand disaster accident in colliery.
And the present inventor just allow for thick aqueous soil layer be in seal water conservation laminated structure state, therefore,
Propose thick aqueous soil layer sand control coal and rock pillar for safety under a kind of new hydraulic pressure effect stays equipment, method.
As shown in Figure 4, for the present invention provide hydraulic pressure effect under thick aqueous soil layer sand control coal and rock pillar for safety stay the side of setting
The flow chart of method, as shown in Figure 4, the method comprise the steps that
S1, for treating the geological conditions of working seam overlying thick aqueous soil layer, be pointed to the argillic horizon below water-bearing layer
Carry out liquid-limit & plastic-limit test, in order to obtain the liquid of this argillic horizon, plasticity index.
For the geological conditions of the thick aqueous soil layer treating the wedge shaped structure of working seam overlying, utilize overburden rock damage
Peephole chooses many parts of soil samples at the different depth of the argillic horizon being positioned at below water-bearing layer, and many parts of soil samples are carried out liquid, plastic limit
Test, in order to obtain the liquid plasticity index of argillic horizon according to result of the test.Wherein, working seam overlying thick aqueous soil layer is treated
Geological conditions refers to that its loose seam's thickness is not less than 100m, the original hydraulic pressure in water-bearing layer not in 1MPa.
S2, for treating the geological conditions of working seam overlying thick aqueous soil layer, be pointed to the basement rock wind of side, water-bearing layer
Change band rock and be dried saturated water absorption test and slaking test, in order to obtain the dry saturated water suction of bedrock weathering zone rock
Rate and disintegrating property parameter.
For the geological conditions of the thick aqueous soil layer treating the wedge shaped structure of working seam overlying, utilize overburden rock damage
The bedrock weathering zone rock of different depth under unconsolidated formation bottom interface is sampled by peephole, and is dried saturated to each rock sample
Water absorption rate and slaking test, in order to obtain dry saturated water absorption and the disintegrating property parameter of bedrock weathering zone rock.
Wherein, utilize following equation to calculate rock and be dried saturated water absorption:
In formula: s rock is dried saturated water absorption, %；
msRock forces saturated quality, g；
mdQuality after rock drying, g.
S3, the liquid of argillic horizon according to obtaining, plasticity index and the dry saturated water absorption of bedrock weathering zone rock, disintegrate
Performance parameter, determines whether thick aqueous soil layer is positioned in wedge-type seal water conservation laminated structure.
First, according to the liquid of argillic horizon obtained, the dry saturated water absorption of plasticity index and bedrock weathering zone rock, collapse
Solve performance parameter, determine the water-resisting property of argillic horizon and bedrock weathering zone rock.
After being pointed to the argillic horizon below water-bearing layer and carrying out liquid-limit & plastic-limit test, if many parts of soil samples of the argillic horizon obtained
Plasticity index be generally higher than 17, liquidity index is respectively less than 0.25, then illustrate that the clay state of argillic horizon is that low liquid limit is semi-consolidated
State, this clay has poor mobility, hence, it can be determined that argillic horizon has good water-resisting property and the plasticity of difference；Instead
It, if the plasticity index respectively less than 17 of many parts of soil samples of argillic horizon obtained, liquidity index are all higher than 0.25, it is determined that argillic horizon
There is relatively poor water-resisting property and of a relatively high plasticity and (it is pointed out that relatively poor water-resisting property and relatively
High plasticity is that the plasticity with above-mentioned good water-resisting property and difference is compared respectively).
After the bedrock weathering zone rock of different depth is dried saturated water absorption test and slaking test, if obtain
Bedrock weathering zone exists and is dried the rock that saturated water absorption is more than 15% or slake-durability is poor, then in explanation bedrock weathering zone
There is the rock stratum that water-resisting property is good, wedge shape water conservation laminated structure can be collectively forming with argillic horizon；Otherwise, it is determined that bedrock weathering zone rock
Stone has poor water-resisting property.
Secondly, according to the water-resisting property of fixed argillic horizon Yu bedrock weathering zone rock, determine loose aquifer whether position
In wedge-type seal water conservation laminated structure.
If it is determined that argillic horizon and bedrock weathering zone rock are respectively provided with good water-resisting property, it is determined that thick aqueous soil layer is positioned at
In wedge-type seal water conservation laminated structure；Otherwise, it is determined that the easy Draining hook of loose aquifer.
If S4 loose aquifer is positioned at non-tight water conservation laminated structure, it is determined that corresponding with non-tight water conservation laminated structure
The thickness H of sand control coal and rock pillar for safetys。
Wherein, the thickness H of corresponding with non-tight water conservation laminated structure sand control coal and rock pillar for safetysHigh equal to caving zone maximum
Degree HmWith protective layer thickness HbSum, i.e. Hs=Hm+Hb。
Wherein, caving zone height series computing formula, by " buildings or structures, water body, railway and main roadway are pressed coal and opened
Adopt code " and " mine geological hazards handbook " be foundation, such as, medium-hard overburden rocks separate zone production caving zone maximum height HmUse existing
The equation below of technology determines:
In formula, M is mining height, and unit is m.
And protective layer thickness HbCan determine according to the mode determined in above-mentioned technological document equally.Such as medium-hard overburden rocks layering
Working seam can be found in table 1 below value, and A is that monolayer adopts thickness, m.
Table 1 sand control safety coal (rock) post protective layer thickness
If S5 loose aquifer is positioned at sealing water conservation laminated structure, it is determined that the hydraulic pressure corresponding with sealing water conservation laminated structure
The thickness H of the lower sand control coal and rock pillar for safety of effectsp。
S51 is if it is determined that loose aquifer is for sealing water conservation laminated structure, and the exploitation of neighbouring work surface fails to make this water-bearing layer
Water level dredges fall, then basement rock air slaking mud class rock is carried out mining induced fissure expanding test, in order to determine weathered zone mud under hydraulic pressure effect
The resistance grittiness of class rock protective layer can have been lost.
Wherein, the present invention carries out mining induced fissure expanding test to rock sample is to use rock fracture retention of excessive fluid as shown in Figure 5 to burst
Sand expanding test device, this device includes: transparent cylinder container 9, and the top of transparent cylinder container 9 is provided with top cover 4, bottom is provided with
Hollow disk 13, transparent cylinder container 9 is connected with water filling pressue device 1 by the opening on top cover 4, and sets on pipeline connecting
Having effusion meter 2, the sidewall of transparent cylinder container 9 connects Pressure gauge 6 and overflow valve 7, and the bottom of transparent cylinder container 9 is provided with collection
Water tank 14.It is respectively equipped with flange, top cover 4 and hollow disk 13 at the top of transparent cylinder container 9 and bottom and passes through screw respectively
It is connected on the flange of transparent cylinder container 9 top and bottom (on screw, being set with rubber sheet gasket 5), the flange of bottom and open circles
Dish 13 is fixed on base.Additionally, also include that (this rock sample 11 is used for being placed in transparent cylinder container 9 for being placed in rock sample 11
In) on rigidity pad 12 and for the overcoat 10 that is wrapped in outside rock sample.
Mud class rock under unconsolidated formation taken from by rock sample during test, the high footpath a size of 50*60mm of rock sample, arranges and split in the middle part of rock sample
Gap, the width in crack uses pad to control, and e.g., making crack gasket width is 10mm, and thickness is 0.2mm.During water filling, pressure sets
It is set to 0.1～0.15MPa, the crack propagation feature of sample during viewing test.
When use the present invention rock fracture retention of excessive fluid burst sand expanding test device realize adopt rock fracture expanding test time,
First, rock sample is put into transparent cylinder container, above rock sample, leave the space for water filling.Owing to rock sample is cylindric knot
Structure, before therefore rock sample being put into transparent cylinder container, cuts the rock sample of cylindrical-shaped structure as initial crack along longitudinal axis,
Rigidity pad is set at the position of the close both sides in the face of incision, and by the width in the initial crack of THICKNESS CONTROL of rigidity pad,
Tightly wrapping with overcoat afterwards, the external diameter making the rock sample after tightly wrapping is suitable with the internal diameter of transparent cylinder container.Then, added by water filling
Pressure device controls hydraulic pressure, nourishment source water filling in transparent cylinder container in simulation water-bearing layer.Afterwards, by applying different water
Pressure observes crack propagation situation of change amount, records the change of water pressure simultaneously, and collects leakage in process of the test by header tank
The muddy water lost.
By the rock fracture retention of excessive fluid of present invention sand expanding test device of bursting, mud class rock is carried out mining induced fissure expanding test,
By laboratory test, the crack propagation rule adopting rock tentatively can be detected, in order to determine that weathered zone mud class rock is protected
The resistance grittiness of layer can have been lost.
The test of the present invention shows that under hydraulic pressure effect, the resistance grittiness of weathered zone mud class rock protective layer can have been lost, now,
If the thickness of sand control coal and rock pillar for safety is still according to the sand control safety coal corresponding with non-tight water conservation laminated structure being determined above
The thickness H of rock pillarsCarry out staying setting, then sand disaster of bursting can occur, therefore, it is necessary to coal petrography safe to the sand control under hydraulic pressure effect again
Post thickness rationally determines.
S52, determine the sand control coal and rock pillar for safety thickness that seals under water conservation laminated structure can not according to non-tight water conservation pressure
The thickness H of the sand control coal and rock pillar for safety that structure is correspondingsAfter carrying out staying and setting, rationally determine the coal column lesion thickness under hydraulic pressure effect
Hp。
Coal column lesion thickness H under hydraulic pressure effectpDetermination by bedrock weathering zone rock is made a strength test
Method.
During test, the bedrock weathering zone rock of the different depth being first pointed to side, water-bearing layer carries out core boring sampling, so
After utilize rock point load instrument that many parts of test specimens are carried out Point Load Tests, it is thus achieved that the point load strength value of each test specimen.
Wherein, the computing formula of point loading strength uses " Standard for test methods of engineering rock masses (GB/T 50266
99) the point load strength computing formula " advised:
In formula: IsUncorrected point load strength, MPa；
Total load head when P test specimen destroys under point loading effect, N；
DeEquivalence core diameter, mm；
Distance between the 2 loading points that D measures on test specimen surface of fracture, mm；
WfLoading point continuous print mean breadth, mm it is perpendicular on test specimen surface of fracture.
After obtaining the point load strength value of each test specimen, each point load strength value must be converted into standard point load intensity value,
Equation below is utilized during conversion:
The computing formula of standard point load intensity is:
Is(50)=F Is (5)
In formula: F-correction factor, when D<during 55mm, correction factor F=0.2717+0.01457D, as D>=55mm, repair
Positive coefficient F=0.754+0.0058D.
Utilize the standard point load intensity value of each test specimen obtained, draw the standard point load intensity of bedrock weathering zone rock
With the Changing Pattern of distance unconsolidated formation bottom interface different depth, and according to Changing Pattern, determine that bedrock weathering zone rock is got the bid
The depth bounds that load intensity is corresponding when being zero on schedule.
Generally, bedrock weathering zone rock (this section of bedrock weathering zone rock in the range of distance Moderate and Thick Unconsolidated Formation certain depth
For mud class rock) standard point load intensity be zero, illustrate that this section of rock decay is serious, between granule, glutinous poly-effect is destroyed, because of
This, depth capacity corresponding when being zero by the standard point load intensity of mud class rock is defined as coal column lesion thickness.
S53, coal column lesion thickness H under being reasonably determined hydraulic pressure effectpAfter, determine corresponding with thick aqueous soil layer
Hydraulic pressure effect under the thickness H of sand control coal and rock pillar for safetysp.Wherein, the thickness H of sand control coal and rock pillar for safety under hydraulic pressure effectsIt is equal to
Caving zone maximum height Hm, protective layer thickness HbWith coal column lesion thickness HpSum, i.e. Hsp=Hm+Hb+Hp。
Wherein, caving zone maximum height HmWith protective layer thickness HbUse and non-tight water conservation laminated structure loose aquifer phase
The thickness H of corresponding sand control coal and rock pillar for safetysIn caving zone maximum height HmWith protective layer thickness HbNumerical value.
S6, stay according to the above-mentioned sand control coal and rock pillar for safety determined and set thickness, treat the sand control safety of exploitation loose aquifer
Coal petrography post carries out staying setting.
Wherein, however, it is determined that loose aquifer is for sealing water conservation laminated structure, then according to anti-under above-mentioned sealing water conservation laminated structure
Sand coal and rock pillar for safety thickness HspThe thickness that computing formula calculates carries out staying setting；If it is determined that loose aquifer is non-tight water conservation pressure
Structure, then according to above-mentioned with sand control coal and rock pillar for safety thickness H under non-tight water conservation laminated structuresThe thickness that calculates of computing formula
Degree carries out staying setting.
As the above analysis, when loose aquifer is for sealing water conservation laminated structure, the sand control safety coal of the present invention is used
Thickness computing formula, increases a coal column lesion thickness than the sand control coal and rock pillar for safety thickness equations of prior art
Hp, during so that it is guaranteed that exploit under similar geological conditions water body, sand accident of bursting will not occur.
Below, as a example by the work surface of Zhao Gu mono-ore deposit 11071 and 11191, the specific implementation method of the present invention is illustrated.
Wherein, Zhao Gu mono-ore deposit 11071 work surface is the geological conditions of thick aqueous soil layer wedge-type seal, loose seam's thickness 380～520m,
Unconsolidated formation bottom aquifer hydraulic pressure is up to 4MPa.Stay according to the regulation of place where troops were originally stationed sand coal and rock pillar for safety and set (that is, sand control coal and rock pillar for safety
Thickness equations be Hs=Hm+Hb), there occurs routed sand disaster；And 11191 work surfaces and the geological conditions of 11071 work surfaces
Similar, according to the method for the present invention, 11191 work surfaces are exploited, it is achieved that safe working.
Below, it is specifically described the method for the present invention being applied to Zhao Gu mono-ore deposit 11191 work surface.
(1) argillic horizon character bottom water-bearing layer.Utilize overburden rock damage peephole different in buried depth 460～520m scope
The degree of depth takes 5 parts of soil samples, and soil sample is carried out liquid-limit & plastic-limit test, and test result is as shown in table 2.
The liquid-limit & plastic-limit test result of table 2 soil sample
As shown in Table 2, the plasticity index of soil sample is both greater than 17, average 17.64 substantially, it is considered that plasticity index is more than 10
There is water-resisting property, have good water-resisting property more than 17；Liquidity index is respectively less than 0.25, and the state of this clay is the semi-consolidated shape of low liquid limit
State, shows that this clay has poor mobility, poor plasticity, and the exploitation of other Adjacent Working Faces can be made without thin fall to burning into sand layer water
Effect, the high hydraulic pressure of retaining clip layer of sand.
(2) saturated water absorption test it is dried.When measuring the dry saturated water absorption of rock, it is generally required to boiling method or vacuum
Rock sample is forced saturated by degassing method.This test uses the GZX-9076MBE number electric drying oven with forced convection rock sample to taking
Being dried, carry out rock sample and force saturated, try to achieve rock and be dried saturated water absorption under boiling conditions, main experimental process is:
Be dried, force saturated, filter weigh, process of the test is same as the prior art, is not described its process at this.
Carry out processing visible to result of the test, mud class rock in rock, the dry saturated water absorption of sandstone are with apart from loose
The increase of the layer bottom interface degree of depth is on the whole in first reducing the rule tended to be steady afterwards.The most as shown in Figure 6: being dried of mud class rock is full
Relatively big with water absorption rate, in the range of unconsolidated formation 0～8m, reach more than 30%, illustrate that air slaking mud class rock has good obstruct aqueous
Energy；And the dry saturated water absorption of sandstone fluctuates in the range of 0.5～2.5%, illustrate that the resistance water isolating of sandstone is poor.
In conjunction with borehole data, the rock section of distance unconsolidated formation 0～10m scope, mud class rock accounts for larger proportion, and mud class rock
In, distance unconsolidated formation 0～5m is based on aluminum matter mud stone, apart from unconsolidated formation 5～10m based on Sandy Silt, therefore this section of mud class
Rock and argillic horizon can be collectively forming wedge shape water conservation laminated structure.
(3) slaking test.Test uses indoor disaggregation test, is put into boring sample in beaker, and note clear water is to flooding
No test specimen, at set intervals observed and recorded test specimen disintegrate state, observing time is 1min, 5min, 10min, 20min,
30min, 1h, 2h, 4h, 8h, 16h, 24h, and according to disaggregation typoiogical classification table, final for test specimen disintegrate form is classified
Record, Fig. 7 Yu Fig. 8 is respectively the aluminum matter mud stone of distance unconsolidated formation bottom interface 2.5m and 10.3m and the disintegrate state of Sandy Silt,
Fig. 9 is sandstone disintegrate state.
It can be seen that sandstone is not easy disintegrating from slaking test, all without substantially during whole rock sample slaking tests
Change, slake-durability is stronger；Mud class rockfall solution feature is obvious, particularly the aluminum matter mud stone of boundary 0～5m scope at the bottom of distance unconsolidated formation,
Entering water and at once start disintegrate, completely (see Fig. 7), final disintegrate form is I type, II type in basic disintegrate in about 30 minutes；Chiltern mud
Rockfall solution relatively aluminum matter mud stone is slow, and after 24 hours, disintegrate becomes detritus sheet (see Fig. 8).Wherein, I type refers to that disintegrate thing form is mud
Shape, its disintegrate feature is to be immersed in the water at once " disintegrating " in pureed；II type refers to that disintegrate thing form is chip mud, fragment mud
Fragment mud, its disintegrate feature be sample in water be cotton-shaped, powder avalanche, short then a few minutes, long then 20～30min, sample
Product i.e. disintegrate is complete, and disintegrate thing is granular, lamellar chip or fragment, but is still mud with hand rubbing.
Test shows, mud class rock is affected relatively big by weathering, and especially aluminum matter mud stone, weathering makes it tend to clay
Changing, resistance water isolating significantly improves, and is conducive to suppression leaking crevice belt to grow, intercepts and let out under loose aquifer water body；And sandstone
Not easy disintegrating, thus leeding water rent is difficult to make up at Sandstone Section, the supply of acceptant overlying aquifer forms aqueous crack.
Being dried saturated water absorption by rock and slaking test illustrates, under water-bearing layer, thick-bedded clay has with weathered zone mud class rock
There is good water-resisting property, wedge shape water conservation laminated structure, 11191 work surfaces and 11071 work surface geological conditions can be formed similar, thus
Determine that 11071 and 11191 work surfaces meet loose aquifer and are positioned at the requirement sealing water conservation laminated structure.
(4) weathered zone mud class rock mining induced fissure expanding test under hydraulic pressure effect.Test rock sample take from unconsolidated formation bottom interface 0～
Weathered zone mud class rock in the range of 10m, high footpath a size of 50mm*60mm, crack (using pad to control) is set in the middle part of rock sample.Make
Crack gasket width is 10mm, and thickness is 0.2mm, and water injection pressure is set to 0.1～0.15MPa, test specimen during viewing test
Crack propagation feature, test uses structure as shown in Figure 5.
During test, water injection pressure is initially set to 0.1MPa, and test specimen crack is in the moment in through water-bearing layer, it was observed that have point
The tiny current of fork flow out, and water pressure diminishes, and current gradually become water droplet and ooze subsequently, and final without dripping, crack is made up, pressure
It is gradually brought to 0.1MPa, tends towards stability.Mineralogical composition after through water-bearing layer, crack is described, in air slaking mud class lithofraction gap tangent plane
Chance water expands, and makes crack gradually make up, makes up the most completely.After 22min, water injection pressure is suddenly increased to 0.15MPa,
Starting bottom assay device subsequently to drip, gradually form crack, tubular conduit at test specimen plane of weakness, water pressure is obviously reduced, finally
Tend towards stability.Illustrating that rock sample plane of weakness there occurs seepage flow under high hydraulic pressure effect, under the effect of current scour, test specimen crack rushes
Brushing expanding, final extension forms the pipeline of an a diameter of 14mm.Water pressure rule over time is as shown in figure 11.
Result of the test shows, under the conditions of being somebody's turn to do, the critical pressure of air slaking mud class cleft extension is 0.15MPa, and hydraulic pressure exceedes
After the critical pressure of crack propagation, crack propagation is pipeline, and resistance grittiness is lost.Test specimen form such as Figure 12 institute before and after test
Show.
Mining induced fissure expanding test result illustrates, although weathered zone mud class rock has good water isolating, but dynamically
High hydraulic pressure flow action under the easy unstability of structure soften.Affected weathered mudstone by damage due to mining and produced crack, at high hydraulic pressure
Under effect, weathered zone mud class rock mining induced fissure extends further to pipeline, therefore, if using the safe coal petrography of sand control of prior art
The staying of post sets formula and carries out staying of coal thickness and set, then the resistance grittiness of sand control coal and rock pillar for safety weathered zone protective layer can be made to lose
Effect, sand control coal and rock pillar for safety unstability, causes routed sand accident, it is necessary to carry out the coal thickness sealed under water conservation laminated structure rationally
Stay and set.
And it practice, the staying to set and i.e. use above-mentioned H of the sand control coal and rock pillar for safety thickness of work surface 11071sFormula calculates
Gained, when exploitation, work surface 11071 there occurs routed sand accident, therefore, it is necessary to thick to the coal petrography post sealed under water conservation laminated structure
Degree rationally stays and sets.
(5) rock point load strength test.Test can use SD-1 type rock point load instrument, this instrument energy acquisition and recording wink
Between pressure, test rock anisotropic index, the moment point load strength of digital-scroll technique rock, error is less.
Crossheading 1 under 11191 work surfaces#Drill site 1 pushes up 2 and Adjacent Working Face 11171 connection roadway 2#Drill site 2 pushes up 3 and 11171
Crossheading west 3 under work surface#Drill site 3 pushes up 3 two, 2 hole1Roof is detected boring and is carried out core boring sampling, and carries out Point Load Tests.
Then, test gained rock point load intensity is converted into standard point load intensity and carries out data analysis.
The weathered zone rock point load intensity Changing Pattern with the degree of depth is drawn (such as Figure 10 according to standard point load intensity data
Shown in middle a, b).The most as shown in Figure 10, the standard point load intensity of mud class rock and sandstone is with the distance unconsolidated formation bottom interface degree of depth
Increase on the whole in first increasing the rule tended to be steady afterwards.In the range of distance unconsolidated formation bottom interface 0～5m, the rheobase of mud class rock
Originally being zero, illustrate that this stage rock decay is serious, between granule, glutinous poly-effect is destroyed, and 5～21.5m scopes are all with the test degree of depth
Increase and increase.The minimum intensity of sandstone is 2MPa, increases with the test increase of the degree of depth on the whole, illustrate weathering with
The test degree of depth gradually weakens.
(6) consideration hydraulic pressure is to mining induced fissure mud class rock protective layer every the adverse effect of grittiness energy, inventors show that, former
Sand control coal and rock pillar for safety stays on the basis of setting thickness, should increase the coal column lesion thickness H under hydraulic pressure effectp, and utilize formula Hsp
=Hm+Hb+HpCalculate staying of sand control coal and rock pillar for safety under hydraulic pressure effect and set thickness Hsp。
Wherein, according to the point load testing of above-mentioned weathered zone mud class rock, under unconsolidated formation, 0～5m mud class rock air slaking are tight
Weight, intensity is zero, easy disintegrating unstability, forms tubular conduit under the effect of hydraulic pressure, and resistance grittiness can easily be lost.Therefore, can be by pine
Dissipate the mud class rock of 5m under layer and be defined as coal column lesion thickness, i.e. Hp=5m.
Owing to this ore deposit 11191 work surface and 11071 work surface conditions are close, therefore, the present inventor is by according to the present invention's
Hsp=Hm+Hb+HpStaying of the sand control coal and rock pillar for safety that formula calculates sets thickness HspIt is applied to 11191 work surfaces, and stays by this
If thickness HspExploit, it is achieved that safe working.
Result shows, stays the thickness set to carry out according to the equipment, method that stays of sand control coal and rock pillar for safety under the hydraulic pressure effect of the present invention
Exploitation is feasible, and, the method for the present invention is supplementary and perfect, and China's coal mining under water bodies sand control coal and rock pillar for safety stays the side of setting
The theory of method, has the highest practical value.
Although the present invention has been described above with particularity, but the invention is not restricted to this, those skilled in the art can
Modifying with the principle according to the present invention, therefore, the various amendments that all principles according to the present invention are carried out all should be understood to
Fall into protection scope of the present invention.
Claims (10)
1. under hydraulic pressure effect thick aqueous soil layer sand control coal and rock pillar for safety stay an equipment, method, including:
For treating the geological conditions of working seam overlying thick aqueous soil layer, be pointed to the argillic horizon below water-bearing layer carry out liquid,
Plastic limit test, in order to obtain the liquid of argillic horizon, plasticity index；
The bedrock weathering zone rock being pointed to side, described water-bearing layer is dried saturated water absorption test and slaking test, in order to
Obtain dry saturated water absorption and the disintegrating property parameter of bedrock weathering zone rock；
According to the liquid of argillic horizon obtained, plasticity index and the dry saturated water absorption of bedrock weathering zone rock, disintegrating property ginseng
Amount, determines whether thick aqueous soil layer is positioned in sealing water conservation laminated structure；
If thick aqueous soil layer is positioned in sealing water conservation laminated structure, it is determined that the hydraulic pressure effect corresponding with sealing water conservation laminated structure
The thickness H of lower sand control coal and rock pillar for safetysp；
According to the thickness H of sand control coal and rock pillar for safety under the hydraulic pressure effect determinedsp, the sand control coal and rock pillar for safety treating working seam enters
Row stays and sets.
Method the most according to claim 1, it is characterised in that determine the thickness H of sand control coal and rock pillar for safety under hydraulic pressure effectsp
Before, the coal column lesion thickness H under hydraulic pressure effect need to be determinedp。
Method the most according to claim 2, it is characterised in that the coal petrography post lesion thickness H under described hydraulic pressure effectpReally
Surely it is the method by bedrock weathering zone rock is made a strength test.
Method the most according to claim 3, it is characterised in that by described bedrock weathering zone rock is carried out intensity examination
Test so that the coal column lesion thickness H determined under hydraulic pressure effectp, comprise the steps:
The described bedrock weathering zone rock of different depth is carried out point load strength test, in order to obtain the basement rock wind of different depth
Change the intensity data of band rock；
The intensity data obtained is processed, in order to obtain the standard point load intensity of the bedrock weathering zone rock of different depth
Data；
According to the standard point load intensity data obtained, by described basement rock air slaking corresponding when being zero with standard point load intensity
The degree of depth with rock is defined as coal column lesion thickness Hp。
Method the most according to claim 4, it is characterised in that determine the coal petrography post lesion thickness H under hydraulic pressure effectpBefore, also
Mining induced fissure expanding test under hydraulic pressure effect is carried out, in order to determine air slaking under hydraulic pressure effect including to bedrock weathering zone mud class rock
Resistance grittiness with mud class rock protective layer can have been lost.
Method the most according to claim 2, it is characterised in that the thickness H of sand control coal and rock pillar for safety under described hydraulic pressure effectsp
Equal to caving zone maximum height Hm, protective layer thickness HbWith coal column lesion thickness HpSum.
Method the most according to claim 1, it is characterised in that if described thick aqueous soil layer is not located at sealing water conservation pressure knot
In structure, it is determined that the thickness H of the sand control coal and rock pillar for safety corresponding with non-tight water conservation laminated structures。
Method the most according to claim 7, it is characterised in that the described sand control peace corresponding with non-tight water conservation laminated structure
The thickness H of full coal petrography postsEqual to caving zone maximum height HmWith protective layer thickness HbSum.
9. according to the method described in any one of claim 1-8, it is characterised in that described in treat that working seam overlying thick loose is aqueous
Layer is wedge structure.
Method the most according to claim 1, it is characterised in that according to the liquid of argillic horizon, plasticity index and the basement rock that obtain
The dry saturated water absorption of weathered zone rock, disintegrating property parameter, determine under hydraulic pressure effect, whether loose aquifer is positioned at sealing
In water conservation laminated structure, including:
If the plasticity index of described argillic horizon more than 17, liquidity index is less than 0.25, it is determined that described argillic horizon has good
Water-resisting property and the plasticity of difference；
It is dried the rock that saturated water absorption is more than 15% or slake-durability is poor, the most really if described bedrock weathering zone rock exists
Fixed described bedrock weathering zone rock has good water-resisting property；
If described argillic horizon and described bedrock weathering zone rock have good water-resisting property, it is determined that described thick aqueous soil layer position
In sealing in water conservation laminated structure；Otherwise, it is determined that the easy Draining hook of described thick aqueous soil layer.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108663724A (en) * | 2018-06-08 | 2018-10-16 | 中国矿业大学 | A kind of coal mine underground reservoir position selecting method based on Water transfer path |
| CN110927000A (en) * | 2019-10-28 | 2020-03-27 | 中国地质大学（北京） | Method for rapidly evaluating weathering degree of stone cultural relics |
| CN112664192A (en) * | 2020-12-11 | 2021-04-16 | 中国矿业大学 | Method for improving coal mining upper limit in thin bedrock area |
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| CN102865078A (en) * | 2012-04-28 | 2013-01-09 | 中国神华能源股份有限公司 | Method of determining water-preserved mining geological conditions under loose water bearing layer |
| CN104453903A (en) * | 2014-12-01 | 2015-03-25 | 中国矿业大学 | Water-preserved mining method of close-distance coal seam group |
| CN104819898A (en) * | 2015-05-14 | 2015-08-05 | 中国矿业大学(北京) | Mining rock crack extension test device and test method |
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| RU2096618C1 (en) * | 1995-08-21 | 1997-11-20 | Воля Васильевич Егошин | Drill-and-drift method for underground mining of coal seams |
| CN102865081A (en) * | 2012-04-28 | 2013-01-09 | 中国神华能源股份有限公司 | Water-preserved mining method |
| CN102865078A (en) * | 2012-04-28 | 2013-01-09 | 中国神华能源股份有限公司 | Method of determining water-preserved mining geological conditions under loose water bearing layer |
| CN104453903A (en) * | 2014-12-01 | 2015-03-25 | 中国矿业大学 | Water-preserved mining method of close-distance coal seam group |
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| CN108663724A (en) * | 2018-06-08 | 2018-10-16 | 中国矿业大学 | A kind of coal mine underground reservoir position selecting method based on Water transfer path |
| CN108663724B (en) * | 2018-06-08 | 2020-09-04 | 中国矿业大学 | Coal mine underground reservoir position selection method based on water resource transfer path |
| CN110927000A (en) * | 2019-10-28 | 2020-03-27 | 中国地质大学（北京） | Method for rapidly evaluating weathering degree of stone cultural relics |
| CN112664192A (en) * | 2020-12-11 | 2021-04-16 | 中国矿业大学 | Method for improving coal mining upper limit in thin bedrock area |
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