CN109026056A - The horizontal layered rock tunnel critical span calculation method of anchoring beam structure - Google Patents

The horizontal layered rock tunnel critical span calculation method of anchoring beam structure Download PDF

Info

Publication number
CN109026056A
CN109026056A CN201810916146.9A CN201810916146A CN109026056A CN 109026056 A CN109026056 A CN 109026056A CN 201810916146 A CN201810916146 A CN 201810916146A CN 109026056 A CN109026056 A CN 109026056A
Authority
CN
China
Prior art keywords
rock
anchoring
tunnel
lower layer
horizontal layered
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN201810916146.9A
Other languages
Chinese (zh)
Other versions
CN109026056B (en
Inventor
陈建勋
王利宝
巩海筱
刘立明
薛金红
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Changan University
Original Assignee
Changan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Changan University filed Critical Changan University
Priority to CN201810916146.9A priority Critical patent/CN109026056B/en
Publication of CN109026056A publication Critical patent/CN109026056A/en
Application granted granted Critical
Publication of CN109026056B publication Critical patent/CN109026056B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21DSHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
    • E21D9/00Tunnels or galleries, with or without linings; Methods or apparatus for making thereof; Layout of tunnels or galleries
    • E21D9/14Layout of tunnels or galleries; Constructional features of tunnels or galleries, not otherwise provided for, e.g. portals, day-light attenuation at tunnel openings
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10Complex mathematical operations
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00Computer-aided design [CAD]
    • G06F30/30Circuit design
    • G06F30/36Circuit design at the analogue level
    • G06F30/367Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • Theoretical Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Mining & Mineral Resources (AREA)
  • Mathematical Physics (AREA)
  • Data Mining & Analysis (AREA)
  • General Engineering & Computer Science (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Computational Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geometry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Algebra (AREA)
  • Environmental & Geological Engineering (AREA)
  • Evolutionary Computation (AREA)
  • Mathematical Analysis (AREA)
  • Mathematical Optimization (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Pure & Applied Mathematics (AREA)
  • Databases & Information Systems (AREA)
  • Software Systems (AREA)
  • Excavating Of Shafts Or Tunnels (AREA)

Abstract

The invention discloses a kind of horizontal layered rock tunnel critical span calculation methods of anchoring beam structure, tunnel roof mechanics model is equivalent to excavate the anchoring beam model of initial stage, while proposing the computation model of horizontal layered rock interlayer cohesive strength and the specific formula for calculation of cohesive strength;By the theoretical model for being implanted into horizontal layered rock interlayer cohesive strength in traditional excavation width model, the horizontal layered rock tunnel roof critical span consistent with practice of construction has been obtained, has been had great importance for the design and construction of Guidance Levels stratiform surrounding rock tunnel.

Description

The horizontal layered rock tunnel critical span calculation method of anchoring beam structure
Technical field
The invention belongs to technical field of tunnel construction in civil engineering, and in particular to a kind of level for considering interlayer cohesive strength The horizontal layered rock tunnel of stratiform surrounding rock tunnel roof safety excavation span calculation method, especially anchoring beam structure is critical to be opened Dig span calculation method.
Background technique
Beded rock mass is a kind of sedimentary rock with bedded structure.Whole world beded rock mass distributed pole is wide, and it is total to account for about land The 66% of area.Beded rock mass distribution in China's is wider, reaches the 77% of national territorial area, is concentrated mainly on southwest, Central China and northern Shensi Equal areas.Beded rock mass since with typical layer structure, not only deformation and intensity property have apparent anisotropy, and And rock mass damage mechanism and mode are also significantly different from other rock mass.The deformation and failure characteristics of beded rock mass are mainly by rock stratum group It closes and structural plane control often becomes extremely complex engineering problem under construction disturbance.Especially horizontal layer rock mass, by It is in parallelly distribute in structural plane, causes it with apparent transverse isotropy, during constructing tunnel, arch easily occurs The engineering problems such as chip off-falling falling rocks, absciss layer, bending or even partial collapse, out break.Arch chip off-falling falling rocks is horizontal layered rock tunnel Common fault in road construction, seriously threatens construction safety, leads to casualties, increased costs, construction delay.
With the rapid development of China's communication, there is a large amount of Tunnel Engineering, inevitably encounter level Stratiform surrounding rock tunnel, such as the Xishan Tunnel of romote antiquity high speed, the windburn mountain tunnel of often the sparrow small stream tunnel of lucky high speed, the sharp railway that changes Deng.By many years tackling of key scientific and technical problems and engineering practice, some experiences are had accumulated, achieve some scientific achievements, but horizontal layer encloses Engineering problem in rock constructing tunnel is not still solved effectively.To find out its cause, mainly to horizontal layered rock tunnel top Plate mechanical characteristic lacks further investigation, does not establish reasonable horizontal layered rock tunnel mechanics computation model.With common rocks Tunnel is compared, and the vault stability in horizontal layered rock tunnel is most important, and horizontal layered rock has apparent level Layer structure and layered combinations thereof feature, Mechanical Characters of Composite Ground difference between each rock stratum considerably beyond their difference in terms of thickness, and Single layer structure is compared, and interlayer cohesive strength is stronger.Therefore, reasonable tunnel roof mechanics model is established, can be horizontal layer Surrounding rock tunnel stability analysis provides basis, and solves the key of engineering problem in horizontal layered rock constructing tunnel.
Currently, domestic and foreign scholars have carried out a large amount of research to horizontal layered rock tunnel mechanics computation model.It is overall next It sees, mainly uses Slab, beam model, stratified half-space model and mole-coulomb criterion and Hoek-Brown criterion Tunnel roof mechanical behavior is analyzed.Although having obtained some achievements, it generally ignores top in detail design Slate body interlayer cohesive strength, the model for different phase of constructing and the practical goodness of fit be not high so that in constructing tunnel critical across Degree parameter calculating differs greatly with practice of construction scene, affects construction cost and progress.
Summary of the invention
The invention proposes a kind of horizontal layered rock tunnel critical span calculation method of anchoring beam structure, designs The interlayer cohesive strength of tunnel roof mechanics model and horizontal layered rock is fully considered in calculating, and its to excavation span Influence so that calculated result more meets Practical Project, the design and construction to horizontal layered rock tunnel have important guidance Meaning, and construction cost is effectively reduced, improve tunnelling progress.
The specific technical solution of the present invention is as follows:
The horizontal layered rock tunnel critical span calculation method of anchoring beam structure, comprising the following steps:
[1] anchoring beam model is established:
Horizontal layered rock tunnel roof rock mass is reduced to anchoring beam model;
[2] anchoring beam structure interlayer cohesive strength calculates:
[2.1] horizontal layered rock is taken to excavate two layers of rock mass sample of region roof supporting or more, measurement obtains respectively The elasticity modulus of layer rock mass is E1Elasticity modulus with lower layer rock mass is E2, in E2<E1In the case where, according to step [2.2] and step Suddenly [2.3] calculate interlayer cohesive strength g_ anchoring
[2.2] upper layer rock mass and lower layer's rock mass are equivalent to the upper layer beam and lower layer's beam of anchoring beam structure support respectively, and The load q of upper layer beam is calculated separately according to actual parameterOn, lower layer's beam load qUnder, upper layer beam amount of deflection ωOnWith scratching for lower layer's beam Spend ωUnder
Wherein qOn=q11h1+g_ anchoring
qUnder=q11h12h2-g_ anchoring
q1For the vertical active force of country rock, upper layer depth of stratum is h1, bulk density γ1, lower layer's depth of stratum is h2, bulk density is γ2, g_ anchoringFor the interlayer cohesive strength of anchor structure;
[2.3] under the conditions of cooperative transformation, the amount of deflection ω of upper layer beamOnWith the amount of deflection ω of lower layer beamUnderIt is identical, layer is calculated Between cohesive strength
Wherein b1For the longitudinal length of upper layer beam, b2For the longitudinal length of lower layer's beam;
[3] anchoring beam structure critical span calculates:
Critical span is calculated according to lower layer's beam critical load formula of anchor structure
Wherein [σt] be lower layer's beam body ultimate tensile strength, q3For horizontal adjoining rock pressure.
The horizontal layered rock tunnel critical span calculation method of above-mentioned anchoring beam structure, in step [2]
q1=γ H
H=0.45 × 2s-1ω
Wherein H is the height equivlent of tunnel load, and γ is the severe (kN/m of country rock3), s is Grades of Surrounding Rock, and ω is width Influence coefficient, ω=1+i (B-5);The pressure from surrounding rock increment rate that i is that B is every when increasing 1m, B is tunnel width, when B < 5m, takes i =0.2;When B > 5m, i=0.1 is taken.
The horizontal layered rock tunnel critical span calculation method of above-mentioned anchoring beam structure, in step [3]
q3=λ q1
λ is lateral pressure coefficient in formula;Angle of friction (°) is calculated for country rock.
The horizontal layered rock tunnel critical span calculation method of above-mentioned anchoring beam structure, in step [2]
Wherein, beam the moment of inertia in upper layer is I1, lower layer's beam the moment of inertia is I2, b1For the longitudinal length of upper layer beam, b2For lower layer's beam Longitudinal length, a is that roof rock mass excavates span, the x-axis coordinate value in the local coordinate system that x is established by top plate beam section.
The advantageous effects that the present invention has are as follows:
(1) present invention combines the detailed process of conventional tunnel construction, by the tunnel roof mechanics meter of different construction stages It calculates model to be equivalent to excavate the freely-supported beam model after the anchoring beam model of initial stage and excavation disturbance, so that model is more in line with The practice of construction process in tunnel.
(2) present invention calculates theoretical model for excavation width in current constructing tunnel and practice of construction difference is biggish asks Topic analyzes the problem of existing excavation width calculates theoretical model, and it is viscous innovatively to propose horizontal layered rock interlayer The computation model of poly- power and the specific formula for calculation of cohesive strength;It is enclosed by being implanted into horizontal layer in traditional excavation width model The theoretical model of cohesive strength between rock stratum, obtained the horizontal layered rock tunnel roof critical consistent with practice of construction across Degree, has great importance for the design and construction of Guidance Levels stratiform surrounding rock tunnel.
(3) interlayer cohesive strength model of the invention is easily understood, and the tunnel roof critical span formula derived And alphabetical meaning in pilot process formula is clear, relevant parameter is easily obtained, there is stronger operability, and by with The deformation and compared analysis by force parameter that Practical Project (crossbeam loess hills tunnel) monitors, demonstrate the correctness of model.
Detailed description of the invention
Fig. 1 is the present invention in tunnel excavation initial stage country rock diagrammatic cross-section;
Fig. 2 is the present invention in tunnelling intermediate stage country rock diagrammatic cross-section;
Fig. 3 is the present invention in tunnelling later stage country rock diagrammatic cross-section;
Fig. 4 is that tunnel surrounding of the present invention anchors beam model beam body stress sketch;
Fig. 5 is that tunnel surrounding of the present invention anchors beam model beam body shear diagram;
Fig. 6 is that tunnel surrounding of the present invention anchors beam model beam body bending moment diagram;
Fig. 7 is tunnel surrounding beam body model representative section coordinate system axis figure of the present invention;
Fig. 8 is tunnel surrounding simply supported beam model beam body stress sketch of the present invention;
Fig. 9 is tunnel surrounding simply supported beam model beam body shear diagram of the present invention;
Figure 10 is tunnel surrounding simply supported beam model beam body bending moment diagram of the present invention.
Appended drawing reference are as follows: 3-cracks;4-tunnel contours;5-upper layer rock mass;6-lower layer's rock mass.
Specific embodiment
In order to which objects and advantages of the present invention are more clearly understood, below in conjunction with attached drawing and case history, to the present invention It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to Limit the present invention.
Fig. 1-3 gives tunnel excavation initial stage, intermediate stage and later stage country rock diagrammatic cross-section, 5 and 6 in figure Upper layer rock mass and lower layer's rock mass are respectively indicated, 3 excavate the crack in intermediate stage and the formation of later stage rock mass, and 4 indicate tunnel Profile.
In Fig. 1, the hair wide open digging initial stage in tunnel, the disturbance that country rock is subject to is smaller, the support of tunnel roof rock mass both ends Position rock mass still has preferable integrality, and more than top plate two layers of rock mass is constrained by upper and lower rock stratum at this time, is neither able to rotate, also not It can move up and down, therefore tunnel roof rock mass can be reduced to anchoring beam model as shown in Figure 1.Further, due to anchor Gu Liang bears biggish tensile stress on anchored end top, in addition the interference of tunnel ensuing blast construction, so that anchoring beam upper end reaches To the ultimate tensile of rock mass, so that the cracking starts perforation from top to down carries out (as shown in Figure 2), two layers of rock of final top plate The end of body is cracked perforation (as indicated at 3), and two layers of beam body can be rotated along respective end at this time, then tunnel top at this time Plate it is visual be freely-supported beam model.
It should be noted that excavating the functional relation that span a and tunnel width B is not determined in figure, tunnel width B is only Width at tunnel maximum excavation line, for calculating country rock vertical pressure, and excavates span a and refers to tunnel tunnel roof rock mass Face sky span, is that simulation is simplified to tunnel roof rock mass.
In the anchoring beam model of Fig. 1, design parameter assumes as follows: tunnel excavation span is B, and it is a that span is excavated on top; First layer depth of stratum is h from top to bottom at the top of tunnel excavation1, rock stratum elasticity modulus is E1, Poisson's ratio μ1, cohesive force c1, Bulk density is γ1, internal friction angle isSecond layer depth of stratum is h2, rock stratum elasticity modulus is E2, Poisson's ratio μ2, cohesive force is c2, bulk density γ2, internal friction angle is
In traditional tunnel excavation design and simulation calculate, influence of the structure of rock stratum to parameter is not considered generally, So that notional result and the practical biggish difference of generation.It is viscous that the present invention innovatively proposes horizontal layered rock interlayer in calculating The computation model of poly- power and the specific formula for calculation of cohesive strength.It needs to make explanations: if E1>E2, i.e., first layer rock stratum is rigid Degree is greater than second layer rock stratum, then there are cohesive strengths between two layers of rock stratum, and first layer rock mass is by downward cohesive strength, second layer rock Body is by upward cohesive strength.If E1<E2, i.e., first layer rock stratum rigidity is less than second layer rock mass layer rock stratum, then first layer rock stratum meeting Downward additional force is generated to second layer rock stratum, cohesive strength is not present at this time, therefore this example is only to E1>E2The case where account for.
The stress condition of upper layer rock stratum is analyzed first.Excavation initial stage country rock is in lesser state of disturbance, therefore will at this time Tunnel roof model simplification is anchoring beam model, and stress sketch are as shown in Figure 4.It acts in equivalent beam body and is vertically evenly distributed with lotus Carry q (kN/m2) it is vertical active force q by country rock1(kN/m2), rock stratum weight stress q2(kN/m2) and interlayer cohesive strength be g (kN/m2) be formed by stacking.Active force in horizontal direction is then the horizontal adjoining rock pressure q of country rock3(kN/m2).Vertical uniform load The shearing of generation is acted in equivalent beam body by q as shown in figure 5, moment of flexure is as shown in Figure 6.
Further, to q1、q2、q3Specifically solved:
To q1Solve as follows:
q1=γ H
H=0.45 × 2s-1ω
In formula: H is the height equivlent of tunnel load, and γ is the severe (kN/m of country rock3);S is Grades of Surrounding Rock;ω is width Influence coefficient, ω=1+i (B-5);The pressure from surrounding rock increment rate that i is that B is every when increasing 1m, B is tunnel width, when B < 5m, takes i =0.2;When B > 5m, i=0.1 is taken.
To q2Solve as follows:
q21h1
q3=λ q1
In formula: λ is lateral pressure coefficient;Angle of friction (°) is calculated for country rock.
Then act on the vertical uniform load q in equivalent beam body are as follows:
Q=q1+q2+g
The internal force for further analyzing Equivalent Beam, at the spaning middle section (1-1) of the Equivalent Beam of Fig. 4
In formula: M1-1For the moment of flexure (kNm) at spaning middle section (1-1);IzFor the moment of inertia of spaning middle section (1-1);σ1-1 For the direct stress at spaning middle section (1-1);F1sFor shearing suffered by the section (kN);Other symbols are the same.Y is in representative section Coordinate system axis, referring to Fig. 7.
When y is maximized, i.e. ymax=h1When/2, the direct stress that moment of flexure generates is also maximum value, then at section (1-1) Upper limb and lower edge direct stress are as follows:
σ in formula1-1 pressureFor section upper limb compression, σ1-1 is drawnFor section lower edge tensile stress.
Act on the maximum (normal) stress of Equivalent Beam spaning middle section (1-1) upper limb
σOn 1-11-1 pressure+q3
Act on the maximum (normal) stress σ of Equivalent Beam spaning middle section (1-1) lower edgeUnder 1-1Are as follows:
σUnder 1-11-1 is drawn-q3
And in Fig. 4 at the end cross-sectional (2-2) of Equivalent Beam
In formula: M2-2For the moment of flexure (kNm) at end cross-sectional (2-2);IzFor the moment of inertia of end cross-sectional (2-2);σ2-2 For the direct stress at end cross-sectional (2-2);F2sFor shearing suffered by the section (kN);Other symbols are the same.
When y is maximized, i.e. ymax=h1/ 2, the direct stress that moment of flexure generates also should be maximum value, then cut in equivalent beam end The upper limb and lower edge direct stress in face (2-2) are as follows:
σ in formula2-2 is drawnFor section upper limb tensile stress, σ2-2 pressureFor section lower edge compression.
Act on the maximum (normal) stress σ of Equivalent Beam end cross-sectional (2-2) upper limbOn 2-2Are as follows:
σOn 2-22-2 is drawn-q3
Act on the maximum (normal) stress σ of Equivalent Beam end cross-sectional (2-2) lower edgeUnder 2-2Are as follows:
σUnder 2-22-2 pressure+q3
Shear stress at Equivalent Beam end cross-sectional (2-2) are as follows:
F in formula2sFor shear stress suffered by Equivalent Beam end cross-sectional (2-2),Equivalent Beam end cross-sectional (2-2) is to neutral axis Static moment, other symbols are the same.
Maximum shear stress is at the center end cross-sectional (2-2) when i.e. y=0, shear stress are as follows:
It is calculated above as can be seen that calculating the active force for knowing to be subject at anchoring most by the actual loading for anchoring beam Greatly.Moreover, because the tensile strength of rock mass is much smaller than compression strength, so influenced excavating the later period by blast working, compared with The rock mass on the anchored end top of big tensile stress reaches tensile failure at first, cracking as shown in Figures 2 and 3 is generated, to make tunnel Road top plate mechanical model is converted to simply supported beam.
The stress sketch of freely-supported beam model as shown in figure 8, shear diagram as shown in figure 9, bending moment diagram is as shown in Figure 10.
In freely-supported beam model, force analysis process is identical as anchoring beam.Anchor beam model and freely-supported beam model difference portion The stress value of position see the table below listed:
Further, the interlayer cohesive strength of two kinds of beam models is calculated.
It is assumed that two layers of beam is cooperative transformation state, i.e. its amount of deflection is identical.According to structural mechanics theory, beam deflection formula is anchored Are as follows:
Wherein a is that roof rock mass excavates span, the x-axis coordinate value in the local coordinate system that x is established by top plate beam section.
The load q that upper layer beam is subject toOnFor vertical strata pressure q1, weight stress γ1h1With the resultant force of cohesive strength g are as follows:
qOn=q11h1+g
The load q that lower layer's beam is subject toUnderFor vertical strata pressure q11h1, weight stress γ2h2With the resultant force of cohesive strength g Are as follows:
qUnder=q11h12h2-g
Upper layer beam deflection are as follows:
Lower layer's beam deflection are as follows:
According to compatible deformation condition (upper and lower level beam deflection is identical), cohesive strength g is obtained_ anchoringAre as follows:
By upper layer beam the moment of inertia and lower layer's beam the moment of inertiaAbove formula is substituted into respectively, can obtain cohesive strength g_ anchoringAre as follows:
Simply supported beam deflection formula are as follows:
The amount of deflection of upper layer beam are as follows:
The amount of deflection of lower layer's beam are as follows:
Similarly with anchoring beam model, according to compatible deformation condition (upper and lower level beam deflection is identical), cohesive strength g is obtained_ freely-supportedAre as follows:
It is analyzed according to above in relation to constructing tunnel stage different beam model Force Calculation, in anchoring beam anchoring end section Top margin, simply supported beam spaning middle section bottom edge suffered by tensile stress it is maximum, with the gradually application of load, corresponding site reaches at first The ultimate tensile intensity of rock mass, that is, reach destruction at first.Critical span in its destruction, it can by corresponding critical State computation.
According to structural mechanics theory, anchoring back plate critical load is
Anchoring the critical span of back plate is
Simply supported beam span centre bottom edge critical load is
The critical span of simply supported beam top plate is
Finally, incorporation engineering actually verifies the critical span formula proposed.
Country rock relevant parameter is as follows:
It should be noted that fully consider excavation initial stage in the calculating of tunnel critical span and excavate later period rank Requirement under section anchoring two kinds of model cases of beam and simply supported beam, it is to be ensured that excavate the calculated value of span, two can be met simultaneously The requirement of kind model structure.Under normal conditions, critical span takes the minimum value of the theoretical calculation in two kinds of models.
Specific verifying example is given below:
Crossbeam loess hills tunnel is separate tunnel, and corresponding country rock is IV grades;According to field geology sketch situation, top plate upper layer is taken Rock mass sandstone h1=0.5m, lower layer rock mass mud stone h2The longitudinal width b of=0.05~0.1m, beam take unit length 1m;Lower layer's rock mass Ultimate tensile strength [σt]=0.7MPa.E1=10Gpa, E2=5Gpa.The critical span of two kinds of beam models is calculated, as a result It see the table below listed.
Calculated result shows: when considering interlayer cohesive strength, anchoring beam model critical span is 3.36~4.75m, letter Branch beam model critical span is 2.74~3.88m;The minimum critical span in the tunnel is 2.74m under two kinds of models.Without Consider interlayer cohesive strength when, anchoring beam model top plate critical span be 0.14~0.30m, freely-supported beam model critical across Degree is 0.12~0.24m.And in practice of construction, when excavating 3~6m of span, there is flat-top phenomenon in vault in crossbeam loess hills tunnel, produces Raw absciss layer and chip off-falling etc. are more than the situation that critical span just has, and illustrate that the present invention considers the top plate Mechanics Calculation mould of interlayer cohesive strength Type more meets engineering practice, and the minimum critical span 2.74m being calculated matches with actual critical span. And traditional computation model when not considering interlayer cohesive strength is then larger with Practical Project gap, therefore calculation method pair of the invention Have great importance in the design and construction of Guidance Levels stratiform surrounding rock tunnel.

Claims (4)

1. the horizontal layered rock tunnel critical span calculation method of anchoring beam structure, which is characterized in that including following step It is rapid:
[1] anchoring beam model is established:
Horizontal layered rock tunnel roof rock mass is reduced to anchoring beam model;
[2] anchoring beam structure interlayer cohesive strength calculates:
[2.1] horizontal layered rock is taken to excavate two layers of rock mass sample of region roof supporting or more, measurement obtains upper layer rock respectively The elasticity modulus of body is E1Elasticity modulus with lower layer rock mass is E2, in E2<E1In the case where, according to step [2.2] and step [2.3] interlayer cohesive strength g is calculated_ anchoring
[2.2] by upper layer rock mass and lower layer's rock mass be equivalent to respectively anchoring beam structure support upper layer beam and lower layer's beam, and according to Actual parameter calculates separately the load q of upper layer beamOn, lower layer's beam load qUnder, upper layer beam amount of deflection ωOnWith the amount of deflection of lower layer beam ωUnder
Wherein qOn=q11h1+g_ anchoring
qUnder=q11h12h2-g_ anchoring
q1For the vertical active force of country rock, upper layer depth of stratum is h1, bulk density γ1, lower layer's depth of stratum is h2, bulk density γ2, g_ anchoringFor the interlayer cohesive strength of anchor structure;
[2.3] under the conditions of cooperative transformation, the amount of deflection ω of upper layer beamOnWith the amount of deflection ω of lower layer beamUnderIt is identical, it is viscous that interlayer is calculated Poly- power
Wherein b1For the longitudinal length of upper layer beam, b2For the longitudinal length of lower layer's beam;
[3] anchoring beam structure critical span calculates:
Critical span is calculated according to lower layer's beam critical load formula of anchor structure
Wherein [σt] be lower layer's beam body ultimate tensile strength, q3For horizontal adjoining rock pressure.
2. the horizontal layered rock tunnel critical span calculation method of anchoring beam structure according to claim 1, It is characterized in that, in step [2]
q1=γ H
H=0.45 × 2s-1ω
Wherein H is the height equivlent of tunnel load, and γ is the severe (kN/m of country rock3), s is Grades of Surrounding Rock, and ω is widths affect system Number, ω=1+i (B-5);The pressure from surrounding rock increment rate that i is that B is every when increasing 1m, B is tunnel width, when B < 5m, takes i=0.2;B When > 5m, i=0.1 is taken.
3. the horizontal layered rock tunnel critical span calculation method of anchoring beam structure according to claim 1, It is characterized in that, in step [3]
q3=λ q1
λ is lateral pressure coefficient in formula;Angle of friction (°) is calculated for country rock.
4. the horizontal layered rock tunnel critical span calculation method of anchoring beam structure according to claim 1, It is characterized in that, in step [2]
Wherein, beam the moment of inertia in upper layer is I1, lower layer's beam the moment of inertia is I2, a is that roof rock mass excavates span, and x is top plate beam section institute X-axis coordinate value in the local coordinate system of foundation.
CN201810916146.9A 2018-08-13 2018-08-13 The horizontal layered rock tunnel critical span calculation method of anchoring beam structure Active CN109026056B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810916146.9A CN109026056B (en) 2018-08-13 2018-08-13 The horizontal layered rock tunnel critical span calculation method of anchoring beam structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810916146.9A CN109026056B (en) 2018-08-13 2018-08-13 The horizontal layered rock tunnel critical span calculation method of anchoring beam structure

Publications (2)

Publication Number Publication Date
CN109026056A true CN109026056A (en) 2018-12-18
CN109026056B CN109026056B (en) 2019-11-26

Family

ID=64633021

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810916146.9A Active CN109026056B (en) 2018-08-13 2018-08-13 The horizontal layered rock tunnel critical span calculation method of anchoring beam structure

Country Status (1)

Country Link
CN (1) CN109026056B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109900564A (en) * 2019-03-25 2019-06-18 中国电建集团华东勘测设计研究院有限公司 Inter-laminar dislocation band of growing up friction angle measuring method
CN113405908A (en) * 2021-07-26 2021-09-17 中国建筑第五工程局有限公司 Shallow shield tunnel roof stability judgment method

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1209885A1 (en) * 1984-08-10 1986-02-07 Днепропетровский Государственный Ордена Трудового Красного Знамени Проектный Институт "Днепрогипрошахт" Roof support for mine workings
US4618283A (en) * 1984-09-06 1986-10-21 Hilfiker Pipe Co. Archway construction utilizing alternating reinforcing mats and fill layers
CN105138767A (en) * 2015-08-23 2015-12-09 北京工业大学 Deep-buried asymmetric closely spaced tunnel surrounding rock pressure calculation method
CN106066920A (en) * 2016-06-13 2016-11-02 暨南大学 The overlapping tunnel shield-tunneling construction numerical analysis method to underpining Influence of Pile Foundation up and down
CN106529150A (en) * 2016-11-03 2017-03-22 上海隧道工程有限公司 Compound stratum shield tunnel vault load calculation method
CN107194038A (en) * 2017-04-25 2017-09-22 中铁四局集团有限公司 Smooth surface CUMULATIVE BLASTING determination method for parameter in a kind of beded rock mass tunnel
CN107590357A (en) * 2017-10-31 2018-01-16 石家庄铁道大学 A kind of different construction stage Tunnel Stabilities sentence method for distinguishing

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1209885A1 (en) * 1984-08-10 1986-02-07 Днепропетровский Государственный Ордена Трудового Красного Знамени Проектный Институт "Днепрогипрошахт" Roof support for mine workings
US4618283A (en) * 1984-09-06 1986-10-21 Hilfiker Pipe Co. Archway construction utilizing alternating reinforcing mats and fill layers
CN105138767A (en) * 2015-08-23 2015-12-09 北京工业大学 Deep-buried asymmetric closely spaced tunnel surrounding rock pressure calculation method
CN106066920A (en) * 2016-06-13 2016-11-02 暨南大学 The overlapping tunnel shield-tunneling construction numerical analysis method to underpining Influence of Pile Foundation up and down
CN106529150A (en) * 2016-11-03 2017-03-22 上海隧道工程有限公司 Compound stratum shield tunnel vault load calculation method
CN107194038A (en) * 2017-04-25 2017-09-22 中铁四局集团有限公司 Smooth surface CUMULATIVE BLASTING determination method for parameter in a kind of beded rock mass tunnel
CN107590357A (en) * 2017-10-31 2018-01-16 石家庄铁道大学 A kind of different construction stage Tunnel Stabilities sentence method for distinguishing

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
周应麟: "层状岩层围岩隧道稳定性的探讨", 《地下空间与工程学报》 *
徐慎刚: "公路隧道开挖参数解析", 《科技情报开发与经济》 *
罗彦斌等: "考虑层间黏聚力的水平层状围岩", 《中国公路学报》 *
邓祥辉: "水平层状围岩隧道爆破控制技术", 《长安大学学报(自然科学版)》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109900564A (en) * 2019-03-25 2019-06-18 中国电建集团华东勘测设计研究院有限公司 Inter-laminar dislocation band of growing up friction angle measuring method
CN109900564B (en) * 2019-03-25 2021-09-28 中国电建集团华东勘测设计研究院有限公司 Method for measuring friction angle of large interlaminar dislocation belt
CN113405908A (en) * 2021-07-26 2021-09-17 中国建筑第五工程局有限公司 Shallow shield tunnel roof stability judgment method

Also Published As

Publication number Publication date
CN109026056B (en) 2019-11-26

Similar Documents

Publication Publication Date Title
Song et al. Measures for controlling large deformations of underground caverns under high in-situ stress condition–a case study of Jinping I hydropower station
CN107609241A (en) Weak rheology surrounding rock tunnel secondary liner structure rigidity and its decision design method for applying opportunity
CN109026056B (en) The horizontal layered rock tunnel critical span calculation method of anchoring beam structure
CN109083655A (en) A kind of high-ground stress environment stratiform surrounding rock tunnel orientation support reinforcement method
CN108867376A (en) Face anchor system and its construction method after mating type forever
CN113094778A (en) High-ground-stress interbed soft rock tunnel failure mechanism and construction control research method
Chen et al. Failure analysis of a highway cut slope with anti-slide piles
Uge et al. CFG pile composite foundation: its engineering applications and research advances
CN111814234A (en) Construction treatment method for broken rock mass flood discharge tunnel
CN109281686B (en) A kind of horizontal layered rock tunnel critical span calculation method
Sun et al. Analysis of deep foundation pit pile-anchor supporting system based on FLAC3D
CN108119147B (en) A kind of Soft Rock Tunnel Excavation and preliminary bracing method
CN109881683A (en) A kind of more sublevel retaining structures and its construction method for combining artificial earth fill&#39;s grouting reinforcement technique
Zhou et al. Landslide distribution and sliding mode control along the Anninghe fault zone at the eastern edge of the Tibetan Plateau
CN109214064A (en) The horizontal layered rock tunnel critical span calculation method of simple beam structure
CN109255154A (en) The horizontal layered rock interlayer cohesive strength calculation method of anchoring beam structure
CN109359316A (en) The horizontal layered rock interlayer cohesive strength calculation method of simple beam structure
Cheng et al. Stability analysis regarding underground cavern group of Songyang pumped storage power station
Lu et al. Roadway failure and support in a coal seam underlying a previously mined coal seam
Corns et al. Gravity dam design and analysis
Zhu et al. Study on the effect of rock stratum structure on the stability of weakly cemented layered floor and the floor control measures: A case study of Meihuajing Mine
Li et al. Analysis of technical measures for controlling instability of surrounding rock in jointed rock masses
CN110145363A (en) A kind of Roof Control method realized fully mechanized coal face and be caving filling mining transition
Liu et al. Theoretical analysis on soil pressure acting on end-suspended pile supporting structure to foundation pit in soil-rock mixed stratum
Wang et al. Numerical simulation analysis of excavation response of counter-tilt rock slope

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant