ResearchofRockBurstRiskInducedbyMiningandField ...downloads.hindawi.com/journals/ace/2018/2632549.pdfhorizontal stress, and the mining stress ﬁelds are super-imposed on each other

Research ArticleResearch of Rock Burst Risk Induced by Mining and FieldCase in Anticlinal Control Area

Shitan Gu12 Zhimin Xiao 34 Bangyou Jiang 12 Ruifeng Huang5 and Peng Shan34

1State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province andthe Ministry of Science and Technology Shandong University of Science and Technology Qingdao Shandong 266590 China2College of Mining and Safety Engineering Shandong University of Science and Technology Qingdao Shandong 266590 China3College of Civil and Transportation Engineering Hohai University Nanjing 210098 China4Institute of Engineering Safety and Disaster Prevention Hohai University Nanjing 210098 China5Inner Mongolia Urban Planning and Municipal Engineering Design Research Institute Hohhot 010070 China

Correspondence should be addressed to ZhiminXiao sdustxiaozhimin163comandBangyou Jiang jiangbangyou123163com

Received 26 February 2018 Revised 30 August 2018 Accepted 27 September 2018 Published 22 October 2018

Academic Editor Ottavia Corbi

Copyright copy 2018 Shitan Gu et al is is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Stress concentration caused by tectonic stress and mining disturbance in coal mines induces a unique type of rock burst No 3201working face controlled by an anticline structure in the Shandong mining area is used as the research background e formationmechanism for anticlines is analyzed eoretical research shows that the bigger the tectonic couple is the smaller the foundationstiffness and the greater the bending degree and elastic strain energy of the coal will be e distribution characteristics ofabutment pressure and maximum principle stress in anticlinal control areas are analyzed using UDEC numerical software eresults show that rock bursts result from interactions between abutment pressure and residual tectonic stress e ldquoconnection-overlay-separationrdquo phenomenon of abutment pressure presents with working face advancement Furthermore the energycriterion for rock burst initiation is established based on the energy principle Residual energy ldquoE0 ECrdquo and rock burst dangercharacteristics during mining are discussed Based on the simulation results microseismic monitoring data for No 3201 workingface are analyzed and the law of microseismic energy is consistent with the variation law for the residual energy ldquoE0 ECrdquo at thepeak of the simulated abutment pressure e microseismic energy and frequency are higher during mining increasing the risk ofrock burst events It can provide scientific basis for prevention and control of rock burst

1 Introduction

Rock bursts are common dynamic disasters in coal mininge elastic energy of coal and rock is released in the form ofa sudden sharp and violent burst with instantaneous de-struction and rock expulsion e intensity of a rock burstand the resulting damage are more prominent in abnormalstress areas of anticline structures Since the first report ofa British rock burst in 1738 the disaster has spread all overthe world and presents a serious threat to safe mining [1ndash4]Coal and rock geological history in anticline structureshighlights the transformation and presents the geologicalstructure characteristics of rock burst events Complextectonic stress fields and mining stress fields overlap in these

structures which increases the complexity of rock bursts andthe difficulty of controlling them erefore research on themechanism of rock burst prevention has become one of thekey scientific and technical problems in the field of rockmechanics [5 6]

Many scholars at home and abroad have carried outthorough research on themechanism and prevention of rockbursts with remarkable results A series of theories such asenergy theory stiffness theory strength theory and impacttendency theory have been proposed [7ndash10] At presentresearch on the theory of rock burst events is mainly focusedon the crack propagation law energy damage and thestability of the local area on the basis of fracture mechanicsdamage theory and catastrophe theory Dyskin et al [11 12]

HindawiAdvances in Civil EngineeringVolume 2018 Article ID 2632549 10 pageshttpsdoiorg10115520182632549

reported that roadways surrounding rock are affected by theconcentrated compressive stress which leads to the furthergrowth and coalescence of cracks finally causing the crackedsurface to separate and inducing rock burst by the bucklingfailure induces the impact Based on the Griffith energytheory and the associated criterion crack propagation iscoupled with material damage and the critical stress R valueof a rock burst can be determined [13] Some scholars[14ndash17] established a catastrophe structure instability modelfor coal and rock masses and analyzed the stress and stiffnessof the surrounding rock as well as the expansion energy ofcoal and rock masses

e fold rock burst is a special type of rock burst thatoccurs in coal and rock masses Because of the special en-vironment of coal and rock masses and the stress environ-ment the cause of rock bursts in this area is complexWrinkles are usually the result of slow deformation of rockstrata under the influence of horizontal pressure in the regionthat is a fold is formed under longitudinal bending [18] Nearthe fold structure the tectonic stress field is dominated byhorizontal stress and the mining stress fields are super-imposed on each other is produces more intense stressdifferentiation resulting in high energy accumulation andleading to crack propagation coalescence and an irreversibleprocess of nonlinear dynamics Mining in the fold area caneasily cause the release of stress-induced rock bursts whichoften occurs in the axis of the fold [19ndash21] According to thestatistics released by the Tianchi Coal Mine and MentougouMine rock bursts occurred 78 times in the geologicalstructure area and 31 times in the anticlinal belt accountingfor 40 of rock burst events e research indicates that theaxis of the anticline which has a wing angle greater than 45degrees and the turning position form tectonic stress con-centration and accumulate a great deal of elastic energy erock burst induced by mining occurs in these areas [22ndash24]To address the problems such as the lack of early warningmethods and prevention technology for rock bursts manyscholars have conducted thorough research As a result rockbursts can be effectively controlled to a certain extent [25ndash29]

At present the mechanism of fault rock bursts has re-ceived the most attention However there are few studies onevolution laws for tectonic stress mining stress and energyevolution and the control mechanism for tectonic rockbursts No 3201 working face controlled by an anticlinestructure is used as the research background in this papere mechanical model for the anticline is constructed anda theoretical solution for deflection and the elastic strainenergy of the rock beam are deduced e internal factorsthat affect the formation of the anticline and its impact arethen discussed A numerical model of the anticline is alsoestablished using UDEC software and abutment pressureand the maximum principal stress distribution character-istics of the anticline under working faces with differentmining distances are simulated and analyzeden based onthe energy principle the criterion for rock burst initiation isestablished and rock burst danger before the working face inthe anticline-controlled area is studied In addition a mi-croseismic monitoring system is used to monitor the mi-croseismic events during the mining process of No 3201

working face as well as when the working face is close to andfar from the axis of the anticline e characteristics ofmicroseismic events and the rock burst risk are discussed

2 FormationMechanism of Anticline Structure

21 2eoretical Solution for Anticline Formation In a deepstratum environment tectonic stress is the maximumprincipal stress and the direction is generally at a certainangle to the horizontal with the tendency of the coal seamFold formation is closely related to tectonic stress Refer-ences [30ndash32] studied the causes of the Yanshan structure inthe Hubei province in China the Wuxu mine field in theGuangxi province in China and the Taiyuan tilting structurein the Shanxi province in China e results show thattectonic coupling is the source of fold formation ereforethe coal seam is equivalent to theWinker elastic support andthe uniform load of infinite beams and tectonic coupling issimplified to a single couple e fold mechanical model isshown in Figure 1 e left side of the w-axis can formsa syncline structure and the right side can form an anticlinestructure e arbitrary microsection dx in the anticlinalmodel is intercepted and the width of the microsection is 1so that we can analyze the model stress as shown in Figure 2

Based on the force balance of the microsection dx

1113944 Fw 0rArrFs + dFs minusFs + kw dxminus ch dx 0

1113944 M 0rArrMminusMminusdM + Fs + dFs( 1113857 dx

+ kwdx2

2minus ch

dx2

2 0

⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨

⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩

(1)

where Fs is the shear force c is the rock density h is thedepth of the rock stratum M is the rock moment of thecouple k is the foundation stiffness and w is the deflection

Simplification of Formula (1)dFs

dx chminus kw

dM

dx Fs

⎧⎪⎪⎪⎪⎪⎨

⎪⎪⎪⎪⎪⎩

(2)

From the mechanics of materials we obtain

EId2w

dx2 M (3)

where E is the modulus of elasticity and I is the moment ofinertia

By means of Formulas (2) and (3) a deflection equationfor dx supported by the Winker elastic foundation isobtained

EId4w

dx4 + kw ch (4)

From natural boundary conditions and continuousconditions for the beam the solution for Formula (4) and dx

strain energy can be expressed as

2 Advances in Civil Engineering

w M0

k4EI

radic

keminus

k

4EI4

radicx sin

k

4EI

4

1113970

x +ch

k (5)

dVε M2(x) dx

2EI (6)

where dVε is the strain energy of the rock beam macro-section dx

By means of Formulas (3) (5) and (6) anticlinal strainenergy can be defined as follows

V 1113946x

0dVε 1113946

x

0

M20eminus2αtcos2αt

8EI1113888 1113889 dt

M2

064EIα

3minus eminus2αx minus e

minus2αx cos 2αx1113872 1113873

(7)

where α is the characteristic coefficient α k4EI

4radic

and t

only represents integral variable in the articleIn summary the deflection of rock and the strain energy

of microsection dx are closely related to the bending mo-ment and location If the tectonic force is greater and thebending stiffness is smaller the rock beam deflection and

strain energy will increase When mining disturbance occursat the location a great deal of energy stored in the coal androck will be released instantaneously which will easily in-duce rock burst

22 Variation of Anticlinal Elastic Strain Energy under Dif-ferent Factors According to the geological data for No 3coal seam and No 3201 working face in Shandong MineChina themining area is affected by anticline structureserelevant parameters for the calculation are as follows eaverage depth of coal is h 800memean thickness of thecoal seam is 6m e elastic modulus E 28GPa of coal ismeasured using the TAW-2000 electrohydraulic servotesting machine and flexural rigidity is EI 504 times

1010Nmiddotm2 e volumetric weight is c 25 kNm3 For thefoundation stiffness k 10GPa 15GPa and 20GPa areused Based on the measured results for in situ stress usingthe stress-relieving method the ratio of the maximumhorizontal stress to the vertical stress is 13ndash32 e tectonicstress concentration factor is taken as 1 2 and 4 while thecorresponding structural couple isM0 20 times 109Nmiddotm 40 times

109Nmiddotm and 8 times 109Nmiddotm In order to facilitate the analysisusing the control variable method anticline formation andenergy accumulation are researched with variations intectonic stress and foundation stiffness

221 Different Tectonic Couple

(1) Analysis of anticlinal deflection When the foundationstiffness is k 10GPa the tectonic couple is taken as M0

20 times 109Nmiddotm 40 times 109Nmiddotm and 80 times 109Nmiddotm e cor-responding anticlinal deflection curve is shown as Figure 3

It can be seen from Figure 3 that the uplift degree of theanticline is increased with the increase of tectonic couplingwhen foundation stiffness is constant e deflection peak islocated 2m from the center of the w-axis As the distancefrom the center of the w-axis increases the deflection valueof anticlinal with different couple decreases and graduallybecomes consistent However a certain deflection valueremainse greater the anticline uplift is the greater the dipangle of the working face will be

(2) Analysis of anticlinal elastic strain energy When thefoundation stiffness is k 10GPa the tectonic couple istaken as M0 20 times 109Nmiddotm 40 times 109Nmiddotm and 80 times

109Nmiddotm e corresponding anticlinal elastic strain energycurve is shown in Figure 4

It can be seem from Figure 4 that the anticlinal elasticstrain energy increases with the increase of the tectoniccoupling when the foundation stiffness is constant With theincrease of distance from the center of the w-axis elasticstrain energy presents a ldquologarithmic curverdquo change trendthat is it appears to increase first and then gradually be-comes gentle Since there is still a certain amount of upliftdeformation away from the center of the w-axis a largeamount of elastic energy is stored When mining activityoccurs at the anticline control area the superimposition ofthe deformation energy caused by mining stress and the

w

x

M0

Elastic foundationCoal

q = γh

Figure 1 Mechanical model of a fold

q = γh

M

Fs

M + dM

Fs + dFs

p = kw

dx

Figure 2 Stress analysis diagram of the anticlinal microsection dx

Advances in Civil Engineering 3

residual elastic energy increases A small amount of energy isreleased in the form of surface energy and the rest of theenergy is the source of energy for the occurrence of a rockburst At this time if the released energy is greater than theenergy consumed by the damage it will easily lead to shockunder mining disturbance (such as roof fracture movementcoal blasting and mechanical vibrations)

222 Different Foundation Stiffness

(1) Analysis of anticlinal deflection When the tectonic coupleisM0 40 times 109Nmiddotm the foundation stiffness is taken as k

10GPa 15GPa and 20GPa e corresponding anticlinaldeflection curve is shown in Figure 5

It can be seen from Figure 5 that the anticline deflectiondecreases with increased foundation stiffness when thetectonic couple is constant e deflection peak is located2m from the center of the w-axis As the distance from thecenter of the w-axis increases the deflection value decreasesIf key stratum exists in the coal strata and the stiffness of thekey layer is greater the anticline structure is more difficult toform However the greater the stiffness of the key layerstored a large amount of energy the greater the possibility ofrock burst becomes

(2) Analysis of anticlinal elastic strain energy When thetectonic couple is M0 40 times 109Nmiddotm the foundationstiffness is taken as k 10GPa 15GPa and 20GPa ecorresponding anticlinal elastic strain energy curve is shownin Figure 6

It can be seem from Figure 6 that the anticlinal elasticstrain energy decreases with the increase of foundationstiffness when the tectonic coupling is constant A largeamount of elastic strain energy is stored in the anticlinalwing When the mining face is pushed into the area sur-rounding rock stress increases significantly with the influ-ence of mining and the stored elastic strain energy is likelyto be released suddenly increasing risk of rock burst

3 Stress Evolution Law of AnticlineAxis with Mining

31 Establishment of Numerical Model Based on the char-acteristics of anticline structures and rock bursts themechanical response of an anticline structure is simulatedusing UDEC numerical software Considering the largescope of anticline geological structures the numericalmodel is not based on the actual site modeling e modelonly studies the response laws for mining coal stress underthe influence of anticline tectonic structures e design

0 2 4 6 8 10 12 14 16 18 2005

101520253035404550556065

Def

lect

ion

(mm

)

Distance frow W axis (m)

M0 = 2 times 109NmiddotmM0 = 4 times 109NmiddotmM0 = 8 times 109Nmiddotm

Figure 3 Distribution curves of anticlinal deflection with differenttectonic couple

0 2 4 6 8 10 12 14 16 18 200

20000

40000

60000

80000

100000

120000

140000

Elas

tic st

rain

ener

gy (k

J)

Distance from W axis (m)


Figure 4 Distribution curves of anticlinal elastic strain energy withdifferent tectonic couple

0 2 4 6 8 10 12 14 16 18 200

5

10

15

20

25

30

35

Def

lect

ion

(mm

)


k = 10GPak = 15GPak = 20GPa

Figure 5 Distribution curves of anticlinal deflection with differentfoundation stiffness


size of the model is 300m times 180m in the horizontal andvertical directions Coal seam thickness is 6m Horizontalconstraints are applied to the left and right boundaries ofthe model e vertical constraint is applied to the bottomboundary e vertical equivalent load p (p cH) is ap-plied to the top of the model for simulating the over-burdened stratum Volumetric weight c is taken 25 kNm3Buried depth of coal seam H is taken 800m So the verticalequivalent load p cH 25 kNm3 times 800m 20MPa emaximum horizontal principal stress is 3ndash5 times greaterthan the vertical stress [3] erefore an initial horizontalstress of 60MPa is applied to simulate the concentratedstructure stress in the anticlinal axis e MohrndashCoulombmodel is used to calculate the numerical model esimplified model is shown in Figure 7

32 Evolution Law of Abutment Pressure e numericalmodel is explored step by step in the UDEC numericalsoftware monitoring the abutment pressure at the range of60m in front of the coal wall With continuous advancementof the working face the evolution law of abutment pressurein front of the coal wall is obtained as shown in Figure 8 inwhich negative distance between working face and anticlinalaxis indicates that the working face has advanced throughthe anticlinal axis

e following can be seen from Figure 8 (1) In Fig-ures 8(a)ndash(c) with the advancing of working face theabutment pressure increases significantly by the influenceof tectonic stress (2) When the distance is 4m between theworking face and anticlinal axis in Figure 8(c) the max-imum value of the abutment pressure is 60MPa (3) Whenthe working face advances through the anticlinal axis inFigure 8(d) the influence range of the abutment pressuredecreases

rough numerical simulation the ldquoconnection-over-lay-separationrdquo phenomenon of the abutment pressure ispresented between the abutment pressure and the hightectonic stress It is noted that the abutment pressure in front

of the coal wall and high tectonic stress begins to intersect inFigure 8(b)e two overlay each other in Figures 8(b)ndash8(d)and gradually separate in Figure 8(d)

33 Evolution Law of Maximum Principal Stress with MiningInfluence A vertical monitoring line is set up in the anti-clinal axis of the numerical model In the model 7 moni-toring points are established 3 points are located on the roof(above the coal seam 06m 78m and 185m) 3 points arelocated in the floor strata (below the coal seam 053m768m and 1842m) and 1 point is located in the coal seam(above the floor 31m) Using the UDEC numerical softwareto simulate the process of working face advancement theevolution curves for the maximum principal stress in theanticlinal axis are shown in Figure 9

e following can be seen from Figure 9 (1) When themining face is greater than 40m from the anticline axis thecoal seam and floor tectonic stress are not affected by theworking face advancement (2) When the mining face is20ndash40m away from the anticline axis the stress from thecoal seam roof and floor increases as the working facecontinues to advance Additionally the closer the floor rockis to the coal the faster the maximum principal stress valueincreases (3) Tectonic stress in the anticlinal axis increasesrapidly when the distance between the working face and theanticlinal axis is less than 20m When the distance betweenthe working face and anticlinal axis is 4m the maximumvalue for the abutment pressure is reached (4) e roof andfloor have some residual stress when the working face ad-vances through the anticlinal axis

4 Energy Analysis of Rock Burst Risk

41 Energy Criterion of Rock Burst According to the mini-mum energy principle of rock dynamic failure [33] the failurecondition is when the stress exceeds the uniaxial compressivestrength that is σ gt σc Meanwhile the corresponding energyconsumption criterion can be expressed as follows

Ec σ2c2E

(8)

Research on many rock burst cases has shown that rockbursts often occur in brittle coal and rock Under the


0 2 4 6 8 10 12 14 16 18 205000

10000

15000

20000

25000

30000

35000

Elas

tic st

rain

ener

gy (k

J)


Figure 6 Distribution curves of anticlinal elastic strain energy withdifferent foundation stiffness

Coal

Siltstone

Fine sandstone

Medium sandstone

Fine sandstone

Gritstone SandstoneGritstone

Siltstone

Fine sandstone

Sandstone

Fine sandstone

Figure 7 Simplified graphic numerical model


influence of mining disturbance this energy can easily bereleased suddenly accompanied by the occurrence of shockBased on the generalizedHookrsquos law the elastic strain energyof coal in a three-dimensional stress state is calculated asfollows

E0 σ21 + σ22 + σ23 minus 2μ σ1σ2 + σ1σ3 + σ3σ2( 1113857

2E (9)

where E is the elastic modulus μ is Poissonrsquos ratio and σ1σ2 and σ3 stand for the first second and third principlestresses

According to the energy theory [34 35] when the energyreleased from an unstable coal rock system is greater thanthe energy consumed a rock burst will be inducederefore the energy criterion for a rock burst can beestablished as follows

E0 minusEc gt 0 (10)

For specific coal E and u could be assumed to beconstants to a certain extent in order to theoretically analyze

the law of coal seam energy erefore Equations (8) (9)and (10) show that the elastic strain energy depends on theprincipal stress When ldquoE0 gtECrdquo a rock burst may be in-duced in front of the coal wall

42 EnergyAnalysis ofRockBurstDanger e increased areaof abutment pressure in front of a coal wall is a serious riskarea erefore the numerical calculation mainly studies theimpact risk at the peak of abutment pressure According to thetest results for No 3 coal mechanics the coal compressivestrength is σc 188MPa the elastic modulus is E 28GPaPoissonrsquos ratio is μ 032 and Equation (8) can be solved as EC 6311 kJm3 e stress state of the abutment pressure peakfrom numerical simulation is shown in Table 1 in whichnegative distance between working face and anticlinal axisindicates that the working face has advanced through theanticlinal axis and the corresponding curve ldquoE0 minusECrdquo isshown in Figure 10

e following can be seen from Figure 10 (1) When themining face is greater than 40m from the anticline axis the

0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)

The distance between monitoring point and face (m)

Working face advanced 16m80m away from anticlinal axis

(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)

Working face advanced 110m-10m away from anticlinal axis

0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)

Figure 8 e distribution curves of abutment pressure in front of the coal wall with different advancing distances (a) (b) (c) and (d)


residual energy ldquoE0 minusECrdquo at the peak of the abutment pressureincreases slowly and the risk of a rock burst is low (2) In therange of 4ndash40m the residual energy increases rapidly withmining and the risk of a rock burst begins to increase signif-icantly (3) When the distance between the working face and

anticlinal axis is 4m the residual energy ldquoE0 minusECrdquo reachesa maximum value of 306617 kJm3 and the risk of a rockburst is at a maximum (4)When the working face advancesthrough the anticlinal axis the value of ldquoE0 minusECrdquo decreasesso the risk of a rock burst begins to weaken

50 40 30 20 10 0 ndash10 ndash20 ndash30 ndash40

0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)

The distance between face and anticlinal axis (m)

From floor above 31m (coal)

Mining direction

(a)

60 50 40 30 20 10 0 ndash10 ndash20 ndash30 ndash40

0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)


From coal seam below 053mFrom coal seam below 768mFrom coal seam below 1842m

Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)

Figure 9 Distribution curves of maximum principal stress of anticlinal axis (a) (b) and (c)

Table 1 Value of ldquoE0 minusECrdquo at the peak of abutment pressure with dierent advancement steps

Distance between face and anticlinalaxis (m)

Maximum principal stressσ1 (MPa)

Intermediate principal stressσ2 (MPa)

Minimum principal stressσ3 (MPa)

60 4075 1555 105140 4193 1651 144220 5123 1889 14294 1426 1469 39080 4076 2364 1478minus2 4400 1630 1168minus14 3819 1426 9581minus30 3262 1270 8809


5 Field Case

e No 3201 working face microseismic system detector isarranged as shown in Figure 11 e system monitors mi-croseismic events during the mining period for the workingface in an anticlinal structure control areae microseismicmonitoring results are selected during the period from Julyto September 2016 During this period the working faceadvances near the anticlinal axis pushes to the axis andeventually pushes through the axis e events are analyzedstatistically as shown in Figure 12

e following can be seen from Figure 12 (1) When thedistance between the working face and the anticlinal axisexceeds 168m the coal in front of the working face is lessaected by the anticlinial structure Microseismic events andfrequency are mainly aected by the mining factor (2)When the distance between the face and axis is 104ndash168mthe microseismic energy and frequency increase graduallywith continuous advancement of the working face to the

60 50 40 30 20 10 0 ndash10 ndash20 ndash30 ndash40ndash500

0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )

The distance between working face and anticlinal axis (m)

Residual energy PrimeE0ndashECPrime

Mining direction

Figure 10 e ldquoE0 minusECrdquo distribution curve of the abutment pressure peak

ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point

NorthMining area entry

Figure 11 e arrangement diagram of No 3201 working face microseismic system detector

201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m

Microseismic energyFrequencyAnticlinal axis

Figure 12 Statistical analysis of No 3201 working face micro-seismic events


axis (3) When the distance between the face and the axis isless than 104m the superposition of high tectonic stress andmining stress causes the abutment pressure to increasesignificantly resulting in higher microseismic energy andfrequency (4)When the face advances through the anticlinalaxis reaching 60m from the axis the control of the anticlinestructure is weakened and the microseismic energy andfrequency are also reduced From this analysis it can be seenthat the variation law for microseismic energy with thedistance between the working face and the axis is consistentwith the variation law for the residual energy ldquoE0 minusECrdquo at thepeak of the simulated abutment pressure

6 Conclusions

(1) Based on the Winker elastic foundation theory amechanical model for an anticline structure isconstructed and theoretical solutions for the de-flection and elastic strain energy of a rock beam arededuced e distribution features of rock beamdeflection and elastic strain energy with the changeof foundation stiffness and structural coupling arealso evaluated using a control variable method forexploring internal factors of anticline formation andthe associated rock burst

(2) Affected by high tectonic stress from an anticlinalstructure the ldquoconnection-overlay-separationrdquophenomenon of abutment pressure is presentedbetween the abutment pressure and high tectonicstress with working face advancement Moreoverthe connection area and the overlay area are atserious risk of a rock burst

(3) While the working face remains close to the anticlineaxis the stress from the roof and floor and theremaining energy value ldquoE0 minusECrdquo of the abutmentpressure peak increases continuously When theworking face advances through the anticlinal axisthe principal stress and residual energy begin todecrease However there are still residual stresseswhich follow certain law distributions with mining

(4) e field example shows that the microseismic en-ergy and frequency are affected by high tectonicstress and mining stress and they increase signifi-cantly which are associated with the possibility ofrock bursts

Data Availability

e data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

e authors declare that they have no conflicts of interest

Acknowledgments

is work was supported by the State Key ResearchDevelopment Program of China (No 2016YFC0801403)

the Shandong Provincial Natural Science FoundationChina (ZR2018MEE009) and Open project fund for StateKey Laboratory of Mining Disaster Prevention and ControlCofounded by Shandong Province and the Ministry ofScience and Technology (MDPC2017ZR04)ese financialaids are gratefully acknowledged

References

[1] B H G Brady and E T Brown Rock Mechanics For Un-derground Mining Springer Dordrecht Holland Nether-lands 3rd edition 2004

[2] S T Gu B Y Jiang Y Pan and Z Li ldquoBending momentcharacteristics of hard roof before first breaking of roof beamconsidering coal seam hardeningrdquo Shock and Vibrationvol 2018 Article ID 7082951 22 pages 2018

[3] Q X Qi and L M Dou2eory and Technology of Rock BurstChina University of Mining and Technology Press XuzhouChina 2008

[4] R Patynska ldquoe consequences of rock burst hazard forSilesian companies in Polandrdquo Acta Geodynamica Et Geo-materialia vol 10 no 2 pp 227ndash235 2013

[5] T B Zhao W Y Guo Y L Tan C P Lu and C W WangldquoCase histories of rock bursts under complicated geologicalconditionsrdquo Bulletin of Engineering Geology and the Envi-ronment pp 1ndash17 2017

[6] G F Wang S Y Gong Z L Li L M Dou W Cai andY Mao ldquoEvolution of stress concentration and energy releasebefore rock bursts two case studies from Xingan Coal mineHegang Chinardquo Rock Mechanics and Rock Engineeringvol 49 no 8 pp 3393ndash3401 2016

[7] Y L Tan F H Yu J G Ning and T B Zhao ldquoDesign andconstruction of entry retaining wall along a gob side underhard roof stratumrdquo International Journal of Rock Mechanicsand Mining Sciences vol 77 pp 115ndash121 2015

[8] N GW Cook E Hoek J P G Pretorius W D Ortlepp andM D G Salamon ldquoRock mechanics applied to the study ofrock burstsrdquo Journal of the South African Institute of Miningand Metallurgy vol 65 pp 437ndash446 1965

[9] A Z Hua and M Q You ldquoRock failure due to energy releaseduring unloading and application to underground rock burstcontrolrdquo Tunnelling and Underground Space Technologyvol 16 no 3 pp 241ndash246 2001

[10] B Jiang L Wang Y Lu C Wang and D Ma ldquoCombinedearly warning method for rockburst in a Deep Island fullymechanized caving facerdquo Arabian Journal of Geosciencesvol 9 no 20 p 743 2016

[11] A V Dyskin and L N Germanovich ldquoModel of rockburstcaused by cracks growing near free surfacerdquo in Rockbursts andSeismicity in Mines R P Young Ed pp 169ndash174 RotterdamBalkema 1993

[12] X C Zhang A H Lu and J Q Wang ldquoNumerical simulationof layer-crack structure of surrounding rock and rock burst inroadway under dynamic disturbancerdquoChinese Journal of RockMechanics and Engineering vol 25 no S1 pp 3110ndash31142006

[13] Q X Huang and S N Gao ldquoe damage and fracture me-chanics model of roadway rock burstrdquo Journal of China CoalSociety vol 26 no 2 pp 156ndash159 2001

[14] Y Pan Y Liu and S F Gu ldquoFold catastrophe model ofmining fault rock burstrdquo Chinese Journal of Rock Mechanicsand Engineering vol 20 no 1 pp 43ndash48 2001

[15] X S Liu Y L Tan J G Ning Y W Lu and Q H GuldquoMechanical properties and damage constitutive model of


coal in coal-rock combined bodyrdquo International Journal ofRock Mechanics and Mining Sciences vol 110 pp 140ndash1502018

[16] A M Linkov ldquoEquilibrium and stability of rock massesrdquoEighth International Congress on Rock Mechanics vol 3pp 1049ndash1054 1997

[17] W Y Guo Y L Tan F H Yu et al ldquoMechanical behavior ofrock-coal-rock specimens with different coal thicknessesrdquoGeomechanics and Engineering vol 15 no 4 pp 1017ndash10272018

[18] Z C Zhu B Z Wei and S Zhang Structural Geology ChinaUniversity of Geosciences Press Beijing China 1999

[19] Aweil Rock Burst China Coal Industry Publishing HomeBeijing China 1959

[20] S M Lee B S Park and S W Lee ldquoAnalysis of rock burststhat have occurred in a waterway tunnel in Koreardquo In-ternational Journal of Rock Mechanics and Mining Sciencesvol 3 no 41 pp 1ndash6 2004

[21] T B Zhao W Y Guo Y L Tan Y C Yin L S Cai andJ F Pan ldquoCase studies of rock bursts under complicatedgeological conditions during multi-seam mining at a depth of800mrdquo Rock Mechanics and Rock Engineering vol 51 no 5pp 1539ndash1564 2018

[22] L Chen P Li G Liu W Cheng and Z Liu ldquoDevelopment ofcement dust suppression technology during shotcrete in mineof China-A reviewrdquo Journal of Loss Prevention in the ProcessIndustries vol 55 pp 232ndash242 2018

[23] Y L Tan F H Yu and L Chen ldquoA new approach forpredicting bedding separation of roof strata in undergroundcoalminesrdquo International Journal of Rock Mechanics andMining Sciences vol 61 pp 183ndash188 2013

[24] S T Gu Z M Xiao and R F Huang ldquoDanger mechanism ofrock burst induced by mining in synclinal influence areardquoElectronic Journal of Geotechnical Engineering vol 20 no 12pp 5103ndash5114 2015

[25] V Frid ldquoCalculation of electromagnetic radiation criterionfor rock burst hazard forecast in coal minesrdquo Pure and Ap-plied Geophysics vol 158 no 5 pp 931ndash944 2001

[26] G C Zhang S J Liang Y L Tan F X Xie S J Chen andH G Jia ldquoNumerical modeling for longwall pillar designa case study from a typical longwall panel in Chinardquo Journalof Geophysics and Engineering vol 15 no 1 pp 121ndash1342018

[27] S K Sharan ldquoA finite element perturbation method for theprediction of rock burstrdquo Computers and Structures vol 85no 17 pp 1304ndash1309 2007

[28] P K Kaiser and M Cai ldquoDesign of rock support systemunder rock burst conditionrdquo Journal of Rock Mechanicsand Geotechnical Engineering vol 4 no 3 pp 215ndash2272012

[29] A C Adoko G Gokceoglu L Wu and Q J ZuoldquoKnowledge-based and data-driven fuzzy modelingfor rock burst predictionrdquo International Journal of RockMechanics and Mining Sciences vol 61 no 7 pp 86ndash952013

[30] G S Zhang ldquoStructural characteristics of Yanshan period ofSoutheastern Hubei and itrsquos rock control and ore controlrdquoHubei Geology vol 6 no 2 pp 16ndash29 1992

[31] C Zhang ldquoStudy on the stages and force sources of tectonicstress field in Wuxu ore area Hechi City Guangxirdquo GuangxiGeology vol 13 no 2 pp 7ndash10 2000

[32] Q L Wang M C Yun and H S Wang ldquoCharacteristics andits formation analysis of Taiyuan tilting structurerdquo NorthWestern Geology vol 43 no 3 pp 41ndash46 2010

[33] Y S Zhao Z C Feng and Z J Wan ldquoLeast energy principleof dynamical failure of rock massrdquo Chinese Journal of RockMechanics and Engineering vol 22 no 11 pp 1781ndash17832003

[34] H P Xie Y Ju and L Y Li ldquoCriteria for strength andstructural failure of rocks based on energy dissipation andenergy release principlesrdquo Chinese Journal of Rock Mechanicsand Engineering vol 24 pp 3003ndash3010 2005

[35] N G W Cook ldquoA note on rockburst considered as a problemof stabilityrdquo Journal of South African Institute of Mining andMetallurgy vol 65 pp 437ndash446 1965


International Journal of

AerospaceEngineeringHindawiwwwhindawicom Volume 2018

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Hindawiwwwhindawicom Volume 2018


Active and Passive Electronic Components

VLSI Design



Shock and Vibration


Civil EngineeringAdvances in

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Journal of

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Hindawiwwwhindawicom

Volume 2018

Hindawi Publishing Corporation httpwwwhindawicom Volume 2013Hindawiwwwhindawicom

The Scientific World Journal

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Control Scienceand Engineering

Journal of



Journal ofEngineeringVolume 2018

SensorsJournal of



RotatingMachinery


Modelling ampSimulationin EngineeringHindawiwwwhindawicom Volume 2018


Chemical EngineeringInternational Journal of Antennas and

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Navigation and Observation


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wwwhindawicom Volume 2018

Advances in

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Submit your manuscripts atwwwhindawicom

reported that roadways surrounding rock are affected by theconcentrated compressive stress which leads to the furthergrowth and coalescence of cracks finally causing the crackedsurface to separate and inducing rock burst by the bucklingfailure induces the impact Based on the Griffith energytheory and the associated criterion crack propagation iscoupled with material damage and the critical stress R valueof a rock burst can be determined [13] Some scholars[14ndash17] established a catastrophe structure instability modelfor coal and rock masses and analyzed the stress and stiffnessof the surrounding rock as well as the expansion energy ofcoal and rock masses

e fold rock burst is a special type of rock burst thatoccurs in coal and rock masses Because of the special en-vironment of coal and rock masses and the stress environ-ment the cause of rock bursts in this area is complexWrinkles are usually the result of slow deformation of rockstrata under the influence of horizontal pressure in the regionthat is a fold is formed under longitudinal bending [18] Nearthe fold structure the tectonic stress field is dominated byhorizontal stress and the mining stress fields are super-imposed on each other is produces more intense stressdifferentiation resulting in high energy accumulation andleading to crack propagation coalescence and an irreversibleprocess of nonlinear dynamics Mining in the fold area caneasily cause the release of stress-induced rock bursts whichoften occurs in the axis of the fold [19ndash21] According to thestatistics released by the Tianchi Coal Mine and MentougouMine rock bursts occurred 78 times in the geologicalstructure area and 31 times in the anticlinal belt accountingfor 40 of rock burst events e research indicates that theaxis of the anticline which has a wing angle greater than 45degrees and the turning position form tectonic stress con-centration and accumulate a great deal of elastic energy erock burst induced by mining occurs in these areas [22ndash24]To address the problems such as the lack of early warningmethods and prevention technology for rock bursts manyscholars have conducted thorough research As a result rockbursts can be effectively controlled to a certain extent [25ndash29]

At present the mechanism of fault rock bursts has re-ceived the most attention However there are few studies onevolution laws for tectonic stress mining stress and energyevolution and the control mechanism for tectonic rockbursts No 3201 working face controlled by an anticlinestructure is used as the research background in this papere mechanical model for the anticline is constructed anda theoretical solution for deflection and the elastic strainenergy of the rock beam are deduced e internal factorsthat affect the formation of the anticline and its impact arethen discussed A numerical model of the anticline is alsoestablished using UDEC software and abutment pressureand the maximum principal stress distribution character-istics of the anticline under working faces with differentmining distances are simulated and analyzeden based onthe energy principle the criterion for rock burst initiation isestablished and rock burst danger before the working face inthe anticline-controlled area is studied In addition a mi-croseismic monitoring system is used to monitor the mi-croseismic events during the mining process of No 3201

working face as well as when the working face is close to andfar from the axis of the anticline e characteristics ofmicroseismic events and the rock burst risk are discussed

2 FormationMechanism of Anticline Structure

21 2eoretical Solution for Anticline Formation In a deepstratum environment tectonic stress is the maximumprincipal stress and the direction is generally at a certainangle to the horizontal with the tendency of the coal seamFold formation is closely related to tectonic stress Refer-ences [30ndash32] studied the causes of the Yanshan structure inthe Hubei province in China the Wuxu mine field in theGuangxi province in China and the Taiyuan tilting structurein the Shanxi province in China e results show thattectonic coupling is the source of fold formation ereforethe coal seam is equivalent to theWinker elastic support andthe uniform load of infinite beams and tectonic coupling issimplified to a single couple e fold mechanical model isshown in Figure 1 e left side of the w-axis can formsa syncline structure and the right side can form an anticlinestructure e arbitrary microsection dx in the anticlinalmodel is intercepted and the width of the microsection is 1so that we can analyze the model stress as shown in Figure 2

Based on the force balance of the microsection dx

1113944 Fw 0rArrFs + dFs minusFs + kw dxminus ch dx 0

1113944 M 0rArrMminusMminusdM + Fs + dFs( 1113857 dx

+ kwdx2

2minus ch

dx2

2 0

⎧⎪⎪⎪⎪⎪⎪⎪⎪⎪⎨

⎪⎪⎪⎪⎪⎪⎪⎪⎪⎩

(1)

where Fs is the shear force c is the rock density h is thedepth of the rock stratum M is the rock moment of thecouple k is the foundation stiffness and w is the deflection

Simplification of Formula (1)dFs

dx chminus kw

dM

dx Fs

⎧⎪⎪⎪⎪⎪⎨

⎪⎪⎪⎪⎪⎩

(2)

From the mechanics of materials we obtain

EId2w

dx2 M (3)

where E is the modulus of elasticity and I is the moment ofinertia

By means of Formulas (2) and (3) a deflection equationfor dx supported by the Winker elastic foundation isobtained

EId4w

dx4 + kw ch (4)

From natural boundary conditions and continuousconditions for the beam the solution for Formula (4) and dx

strain energy can be expressed as


w M0

k4EI

radic

keminus

k

4EI4

radicx sin

k

4EI

4

1113970

x +ch

k (5)

dVε M2(x) dx

2EI (6)



V 1113946x

0dVε 1113946

x

0


8EI1113888 1113889 dt

M2

064EIα


minus2αx cos 2αx1113872 1113873

(7)


4radic

and t














w

x

M0


q = γh


q = γh

M

Fs

M + dM

Fs + dFs

p = kw

dx












0 2 4 6 8 10 12 14 16 18 2005

101520253035404550556065

Def

lect

ion

(mm

)




0 2 4 6 8 10 12 14 16 18 200

20000

40000

60000

80000

100000

120000

140000

Elas

tic st

rain

ener

gy (k

J)




0 2 4 6 8 10 12 14 16 18 200

5

10

15

20

25

30

35

Def

lect

ion

(mm

)














Ec σ2c2E

(8)



0 2 4 6 8 10 12 14 16 18 205000

10000

15000

20000

25000

30000

35000

Elas

tic st

rain

ener

gy (k

J)



Coal

Siltstone

Fine sandstone

Medium sandstone

Fine sandstone


Siltstone

Fine sandstone

Sandstone

Fine sandstone





2E (9)








0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)



(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)


0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)






0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia


w M0

k4EI

radic

keminus

k

4EI4

radicx sin

k

4EI

4

1113970

x +ch

k (5)

dVε M2(x) dx

2EI (6)



V 1113946x

0dVε 1113946

x

0


8EI1113888 1113889 dt

M2

064EIα


minus2αx cos 2αx1113872 1113873

(7)


4radic

and t














w

x

M0


q = γh


q = γh

M

Fs

M + dM

Fs + dFs

p = kw

dx












0 2 4 6 8 10 12 14 16 18 2005

101520253035404550556065

Def

lect

ion

(mm

)




0 2 4 6 8 10 12 14 16 18 200

20000

40000

60000

80000

100000

120000

140000

Elas

tic st

rain

ener

gy (k

J)




0 2 4 6 8 10 12 14 16 18 200

5

10

15

20

25

30

35

Def

lect

ion

(mm

)














Ec σ2c2E

(8)



0 2 4 6 8 10 12 14 16 18 205000

10000

15000

20000

25000

30000

35000

Elas

tic st

rain

ener

gy (k

J)



Coal

Siltstone

Fine sandstone

Medium sandstone

Fine sandstone


Siltstone

Fine sandstone

Sandstone

Fine sandstone





2E (9)








0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)



(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)


0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)






0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia











0 2 4 6 8 10 12 14 16 18 2005

101520253035404550556065

Def

lect

ion

(mm

)




0 2 4 6 8 10 12 14 16 18 200

20000

40000

60000

80000

100000

120000

140000

Elas

tic st

rain

ener

gy (k

J)




0 2 4 6 8 10 12 14 16 18 200

5

10

15

20

25

30

35

Def

lect

ion

(mm

)














Ec σ2c2E

(8)



0 2 4 6 8 10 12 14 16 18 205000

10000

15000

20000

25000

30000

35000

Elas

tic st

rain

ener

gy (k

J)



Coal

Siltstone

Fine sandstone

Medium sandstone

Fine sandstone


Siltstone

Fine sandstone

Sandstone

Fine sandstone





2E (9)








0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)



(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)


0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)






0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia











Ec σ2c2E

(8)



0 2 4 6 8 10 12 14 16 18 205000

10000

15000

20000

25000

30000

35000

Elas

tic st

rain

ener

gy (k

J)



Coal

Siltstone

Fine sandstone

Medium sandstone

Fine sandstone


Siltstone

Fine sandstone

Sandstone

Fine sandstone





2E (9)








0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)



(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)


0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)






0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia




2E (9)








0 10 20 30 40 50 600

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)



(a)


0 10 20 30 40 50 600

10

20

30

40

50

60

Abu

tmen

t pre

ssur

e (M

Pa)


(b)


0 10 20 30 40 50 60 70

0

10

20

30

40

50

60

70

Abu

tmen

t pre

ssur

e (M

Pa)


(c)


0 5 10 15 20 25 30 35 40 45 50 55 60 650

5

10

15

20

25

30

35

40

Abu

tmen

t pre

ssur

e (M

Pa)


(d)






0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia





0

10

20

30

40

50M

axim

um p

rinci

pal s

tres

s (M

Pa)



Mining direction

(a)


0

10

20

30

40

50

Max

imum

prin

cipa

l str

ess (

MPa

)



Mining direction

(b)



10

20

30

40

50

60

70

Max

imum

prin

cipa

l str

ess (

MPa

)


Mining direction

(c)









5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia


5 Field Case




0

500

1000

1500

2000

2500

3000

3500

Resid

ual e

nerg

y Prime

E 0ndashE

cPrime(k

Jm3 )



Mining direction


ndash760

ndash740

ndash700

ndash740

ndash780

ndash720

ndash720

ndash700ndash680

3201 Working face

Mining area entry

1 Monitoring point

2 Monitoring point



201642 2016416 2016430 2016514 2016528 20166110

50100150200250300350400450500550

Date

Dai

ly m

icro

seism

ic to

tal e

nerg

y (k

Jd)

0

5

10

15

20

25

30

35

40

Fre

quen

cy (t

imes

d)

168m

104m60m





6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia



6 Conclusions





Data Availability




Acknowledgments



References









































RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia


























RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia




RoboticsJournal of




VLSI Design



Shock and Vibration







Journal of



Volume 2018



Volume 2018


Journal of




SensorsJournal of



RotatingMachinery





Propagation






Hindawi


Advances in

Multimedia


Documents

ResearchofRockBurstRiskInducedbyMiningandField ...downloads.hindawi.com/journals/ace/2018/2632549.pdfhorizontal stress, and the mining stress ﬁelds are super-imposed on each other