CN114352358B - Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel - Google Patents
Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel Download PDFInfo
- Publication number
- CN114352358B CN114352358B CN202111628550.4A CN202111628550A CN114352358B CN 114352358 B CN114352358 B CN 114352358B CN 202111628550 A CN202111628550 A CN 202111628550A CN 114352358 B CN114352358 B CN 114352358B
- Authority
- CN
- China
- Prior art keywords
- deformation
- tunnel
- surrounding rock
- relative
- grade
- 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.)
- Active
Links
- 239000011435 rock Substances 0.000 title claims abstract description 101
- 238000000034 method Methods 0.000 title claims abstract description 54
- 230000008093 supporting effect Effects 0.000 claims description 29
- 238000004590 computer program Methods 0.000 claims description 13
- 238000009412 basement excavation Methods 0.000 claims description 12
- 238000010276 construction Methods 0.000 claims description 7
- 230000008569 process Effects 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 5
- 229920006395 saturated elastomer Polymers 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 3
- 229910000831 Steel Inorganic materials 0.000 description 34
- 239000010959 steel Substances 0.000 description 34
- 230000003014 reinforcing effect Effects 0.000 description 11
- 239000004567 concrete Substances 0.000 description 5
- 230000002787 reinforcement Effects 0.000 description 5
- 239000004568 cement Substances 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- 238000005553 drilling Methods 0.000 description 4
- 239000011378 shotcrete Substances 0.000 description 4
- 230000001133 acceleration Effects 0.000 description 3
- 238000004886 process control Methods 0.000 description 3
- 230000001186 cumulative effect Effects 0.000 description 2
- 230000009545 invasion Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000004570 mortar (masonry) Substances 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000005507 spraying Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011440 grout Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
- 238000009966 trimming Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Images
Landscapes
- Lining And Supports For Tunnels (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
Abstract
The invention discloses a dynamic grading control method and a dynamic grading control system for large deformation of a high-ground-stress deep-buried soft rock tunnel, which are used for carrying out grading management and dynamic control on deformation of surrounding rocks, determining control references and control methods at different deformation stages, determining support time of active support measures and passive support measures and conforming to the control concept of 'letting resistance combine, letting first and then resisting' of the high-ground-stress deep-buried soft rock tunnel.
Description
Technical Field
The invention relates to the field of tunnel engineering, in particular to a dynamic grading control method and device for large deformation of a high-ground-stress deep-buried soft rock tunnel.
Background
The deep rock mass has complex structure and high ground stress, and the large deformation of the soft rock caused by the high ground stress belongs to the large deformation with extrudability. The deformation control of the high ground stress deep-buried soft rock tunnel is a project problem which troubles the majority of tunnel builders. The general principle of controlling the large deformation of the soft rock tunnel is to control the deformation of the excavated surrounding rock within an allowable range. For the high ground stress deep-buried soft rock tunnel, the deformation control also follows the control concept of 'letting resist combine, letting resist first and then resist'. Some deformation of the surrounding rock and the supporting structure is allowed in the early stage to sufficiently release the deformation energy accumulated in the surrounding rock. The pressure-yielding measures comprise increasing the reserved deformation and adopting flexible primary support. Common flexible primary support structures include low-stiffness steel arches, retractable steel frames, compressible buffer layers, and the like. In order to ensure the stability of the tunnel and prevent the loosening and damage of the surrounding rocks in the later deformation stage, an active supporting or passive supporting mode is adopted to improve the compression resistance of the surrounding rocks or the supporting structure. The active support refers to actively improving mechanical parameters of tunnel surrounding rock, fully adjusting self-bearing capacity of the surrounding rock, and comprises advanced pre-reinforcement before excavation and section surrounding rock reinforcement after excavation. The advanced pre-reinforcement mainly comprises advanced pre-grouting, an advanced small conduit and an advanced pipe shed. Reinforcing the section surrounding rock, including adding a reinforcing anchor rod, radially grouting the surrounding rock and the like; passive supporting means that the bearing capacity of tunnel support is improved, and the supporting construction provides bigger supporting counter-force to resist the surrounding rock deformation. Common passive support measures include increasing the thickness of concrete, selecting high-rigidity steel arches, reducing the spacing between the steel arches, adding a locking leg pipe shed, multi-layer primary support and the like. Therefore, the large deformation control measures of the high ground stress deep-buried soft rock tunnel are abundant, and the support mechanism, the control capability and the application conditions of different deformation control measures are different.
The deformation of the high ground stress deep-buried soft rock tunnel mainly depends on the surrounding rock strength and the stress environment. The deformation grades of the surrounding rocks are different under different strength stress ratios, and the supporting resistance required by deformation control is also different. In addition, the control concept of 'letting resist combine, letting first then resist' of the high ground stress deep-buried soft rock tunnel emphasizes process control, and staged intervention is carried out according to a deformation development rule in the construction process, so that the tunnel deformation is finally controlled within an allowable range. However, at present, a unified knowledge is not formed aiming at the control measures of the high ground stress deep-buried soft rock tunnel under different deformation levels and different deformation stages, and engineering application is mainly based on experience analogy, so that the supporting measures adopted by actual engineering are either too high in rigidity and not economical, or too low in rigidity and not applicable, the yielding degree of surrounding rocks and the pressure-resistant design of a supporting structure are difficult to grasp, and further the deformation control effect is difficult to guarantee.
Disclosure of Invention
The invention aims to solve the technical problem that the prior art is insufficient, and provides a dynamic grading control method and device for large deformation of a high-ground-stress deep-buried soft rock tunnel, which furthest exert the self-bearing capacity of surrounding rocks and avoid the inapplicability of a supporting structure caused by too early or too late supporting time in actual engineering.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a dynamic grading control method for large deformation of a high-ground-stress deep-buried soft rock tunnel comprises the following steps:
s1, according to the strength-stress ratio R of surrounding rocks c /P 0 Determining the large deformation grade of the tunnel according to the relative deformation epsilon and the relative deformation rate eta of the tunnel, and drawing up the reserved deformation u of the tunnel according to the large deformation grade of the tunnel 1 ；P 0 The ground stress of the tunnel construction face position is obtained; r is c The saturated uniaxial compressive strength of the surrounding rock;
s2, relative deformation rate eta of tunnel>0.8％·d -1 If the time (d represents the unit 'day'), judging that the surrounding rock in front of the tunnel face needs to be actively reinforced by adopting the advance support, and then entering the step S3; when the relative deformation rate eta<0.8％·d -1 If so, directly entering step S3;
s3, judging that the tunnel needs to be excavated step by step, and sealing to form a ring to construct a flexible primary support;
s4, when the accumulated deformation u is larger than a first early warning value and the deformation rate v has no obvious convergence trend (v is not equal to 0), judging that the surrounding rock behind the primary support needs to be reinforced by adopting an active support method; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
when the accumulated deformation u continuously increases to be larger than a second early warning value and the deformation rate v has no obvious convergence trend (v is not equal to 0), judging that the primary support rigidity is improved by adopting a passive support method to control the deformation of the surrounding rock; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
when the accumulated deformation u is still continuously increased to exceedOver-reserved deformation u>u 1 And after the deformation is stable (v = 0), judging that the primary support of the invasion limit needs to be removed and the section of the tunnel needs to be enlarged and excavated, and increasing the reserved deformation to u 2 Applying a reinforced primary support; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
s5, repeating the step S4 until the final accumulated deformation u of the primary support is controlled within the reserved deformation range u i Internal;
wherein the first early warning value is less than the second early warning value and less than u 1 。
The invention carries out graded management on the deformation state of the surrounding rock, thereby defining the reserved deformation amount and the control measure of the surrounding rock with different grades. The grading method provided by the invention considers the relative deformation rate of the surrounding rock, the index represents the maximum acceleration of the deformation of the surrounding rock in a short period after tunnel excavation, the self-stability capability of the surrounding rock on the tunnel face is reflected visually, and the grading method is an important basis for judging whether the tunnel is used for advance support. The invention provides a control method for combining active and passive support, and defines the support time of active support measures and passive support measures. The self-bearing capacity of the surrounding rock can be exerted to the maximum extent, and the economical efficiency of support is improved; and the inadaptability of the supporting structure caused by too early or too late supporting time in the actual engineering can be avoided, and the effectiveness of supporting is ensured. In step S1, the saturated uniaxial compressive strength R of the surrounding rock c The calculation formula of (2) is as follows:
σ 0 for the basic bearing capacity of the tunnel, K represents a reduction coefficient.
The calculation formula of the relative deformation epsilon of the tunnel is as follows:
wherein R is 0 Is the equivalent radius of the tunnel; u. of 0 The maximum deformation of the constructed tunnel segment. The cross sections of different tunnels are designed to have different sizes, and the tunnel with different cross sections is suitable for the tunnel with different cross sections by taking the relative deformation as an indexA horseshoe railway tunnel, the equivalent radius of the tunnel being equal to 1/4 of the sum of the height h and the span b of the tunnel.
In step S1, the calculation formula of the relative deformation rate η is:
wherein v is 0 The maximum deformation rate of the constructed large deformation section tunnel is obtained; r 0 Is the equivalent radius of the tunnel. The cross sections of different tunnels are designed to have different sizes, and the method is suitable for tunnels with different cross sections by taking the relative deformation rate as an index. The invention provides a relative deformation rate index which represents the maximum acceleration of the deformation of the surrounding rock in a short period after the tunnel is excavated, intuitively reflects the self-stability capability of the surrounding rock of the tunnel face and is an important basis for whether the tunnel is applied to advance support.
In step S1, a tunnel reserved deformation u 1 The determination process of (2) includes:
when the stress ratio R of the surrounding rock strength c /P 0 When the relative deformation epsilon and the relative deformation rate eta of the tunnel are respectively 0.25-0.5, 3-5 and 0.3-0.5, determining that the large deformation grade of the tunnel is I grade and the corresponding reserved deformation is 20-30 cm;
when the stress ratio R of the surrounding rock strength c /P 0 When the relative deformation epsilon and the relative deformation rate eta of the tunnel are respectively 0.15-0.25, 5-8 and 0.5-0.8, determining that the large deformation grade of the tunnel is II grade and the corresponding reserved deformation is 40-50 cm;
when the strength-to-stress ratio (R) of the surrounding rock c /P 0 )<0.15, tunnel relative deformation ε>8. Relative rate of deformation η>And when 0.8 hour, determining that the large deformation grade of the tunnel is grade III, and the corresponding reserved deformation is 50-80 cm.
The determination process of the large deformation grade and the reserved deformation comprehensively considers three indexes of the surrounding rock strength-stress ratio, the tunnel relative deformation and the tunnel relative deformation rate. Compared with the existing grading method, the method considers the relative deformation rate of the surrounding rock after the tunnel is excavated, the index can intuitively reflect the self-stability capability of the surrounding rock of the tunnel face, and the method is an important basis for applying the advanced pre-support to the tunnel. And (4) counting the actually measured deformation of the existing high-ground-stress deep-buried soft rock tunnel engineering, and finally determining the reserved deformation of different deformation grades.
The first early warning value is set to 50% 1 (ii) a The second warning value is set to 75% 1 . Setting the early warning value based on the reserved deformation, counting the actual deformation of the tunnel engineering with high ground stress and deep soft rock, and determining by 50% 1 And 75% of u 2 As a first warning value and a second warning value for deformation control.
In the step S2, the advance support measures comprise advance pre-grouting, advance small conduits, advance pipe sheds, horizontal jet grouting and the like. In step S3, the flexible primary support includes a low-rigidity primary support, a retractable steel frame, a compressible buffer layer, and the like. In the step S4, the active reinforcing measures include small guide pipe grouting reinforcement and additional reinforcing anchor rods. The passive supporting measure means that a second layer of steel arch frame is additionally arranged. The reinforced primary support comprises the steps of increasing the thickness of concrete, selecting high-rigidity steel arch frames, reducing the distance between the steel arch frames, adding a locking pin pipe shed and the like.
As an inventive concept, the present invention also provides a computer arrangement comprising a memory, a processor and a computer program stored on the memory; the processor executes the computer program to implement the steps of the method of the present invention.
As an inventive concept, the present invention also provides a computer program product comprising computer programs/instructions; wherein the computer program/instructions, when executed by a processor, performs the steps of the method of the present invention.
A computer readable storage medium having stored thereon a computer program/instructions; which when executed by a processor implement the steps of the method of the present invention.
Compared with the prior art, the invention has the beneficial effects that:
(1) The method of the invention carries out graded management on the deformation state of the surrounding rock, thereby defining the reserved deformation amount and control measures of the surrounding rocks of different grades. Compared with the existing large deformation grading method, the grading method considers the relative deformation rate of the surrounding rock, the index represents the maximum acceleration of the deformation of the surrounding rock in a short period after the tunnel is excavated, the self-stability capability of the surrounding rock on the tunnel face is reflected intuitively, and the grading method is an important basis for whether the tunnel is used for advanced support.
(2) The control method emphasizes the process control, takes the actual measurement deformation of the tunnel as the basis, and takes control measures in stages according to the process control reference so as to finally control the deformation within the allowable range. Compared with the existing large deformation control method, the method provided by the invention is more in line with the control concept of 'letting resistance combination, letting first and then resisting' of the high ground stress deep buried soft rock tunnel. The method mainly comprises the steps of giving priority to 'yielding' in the initial deformation stage, releasing the stress of the surrounding rock by adopting flexible initial support, and fully exerting the self-bearing capacity of the surrounding rock; and (3) mainly taking 'resistance' in the later deformation stage, and controlling the deformation of the surrounding rock by adopting a method of reinforcing the surrounding rock by active support or reinforcing the support by passive support, so as to prevent the deformation of the surrounding rock from exceeding the reserved deformation amount or from being loosened and damaged.
(3) The control method of the invention emphasizes dynamic control and determines control references and control methods of different deformation stages. Compared with the existing large deformation control method, the invention provides a control method combining active and passive support, and defines the support time of active support measures and passive support measures. The self-bearing capacity of the surrounding rock can be exerted to the maximum extent, and the economical efficiency of support is improved; and the inadaptability of the supporting structure caused by too early or too late supporting time in the actual engineering can be avoided, and the effectiveness of supporting is ensured.
Drawings
Fig. 1 is a high ground stress deep-buried soft rock tunnel grading dynamic control schematic diagram in the embodiment of the invention.
Fig. 2 is a supporting time of each control technique of the high-ground-stress deep-buried soft rock tunnel according to the embodiment of the present invention, wherein (1) -advance supporting is performed; (2) constructing a flexible primary branch; (3) -actively reinforcing the surrounding rock; (4) -passive reinforcement support; (5) and removing the primary support of the limit intrusion, enlarging and excavating the section of the tunnel, enlarging the reserved deformation and reinforcing the primary support.
Detailed Description
The embodiment of the invention provides a dynamic grading control method for large deformation of a high ground stress deep-buried soft rock tunnel, which is specifically described by combining the attached drawings of the specification and comprises the following steps:
According to the actual measurement on site, the maximum deformation u of the constructed large deformation section 0 And maximum deformation rate v 0 72cm and 78mm/d, respectively, and the relative deformation ε and the relative deformation rate η of the tunnel were calculated to be 11.52% and 1.25%. D, respectively, based on the equations (2) and (3) -1 . From the strength-to-stress ratio R of the surrounding rock c /P 0 Determining the large deformation level of the railway tunnel to be III level according to the table 1, and drawing up the reserved deformation u of the tunnel 1 ＝80cm。
TABLE 1 Large deformation grade and reserved deformation of high ground stress deep-buried soft rock tunnel
And step 2, judging the self-stability capability of the tunnel face surrounding rock by taking the relative deformation rate eta of the tunnel as a basis, and determining whether to implement advanced support. Relative deformation rate eta of tunnel>0.8％·d -1 Adopting advanced support to actively reinforce the surrounding rock in front of the tunnel face at the support opportunity (1); when the relative deformation rate eta<0.8％·d -1 Go directly to step 3. The advanced pre-reinforcing measures comprise advanced pre-grouting, advanced small guide pipes, advanced pipe sheds, horizontal rotary spraying grouting and the like.
The relative deformation rate eta = 1.25%. D calculated by the embodiment -1 >0.8％·d -1 And the railway tunnel is pre-reinforced with surrounding rocks by adopting an advanced pipe shed on site. The parameters of the pipe shed are phi 76, the wall thickness s =5mm and the length of a single hot-rolled seamless steel pipe is 6m. During specific construction, a hydraulic pipe shed drilling machine is used for drilling a row of holes into a stratum in a fan shape along the arch part of a tunnel excavation working surface, the diameter of each hole is 20-30 cm larger than the diameter of a steel pipe, the external insertion angle of each hole is about 1-2 degrees, and the distance between every two holes is 40cm. And then, inserting a steel pipe into the drilled hole to form a pipe shed, wherein the overlapping length of the front row of pipe sheds and the rear row of pipe sheds is 3.6m. The steel pipe wall is provided with quincunx grouting holes, cement slurry is injected into the stratum through the grouting holes in the pipe wall to reinforce the steel pipe and the stratum, and the grouting pressure is controlled to be 0.5-1.0 MPa until the cement slurry is returned from the orifice or the pump pressure reaches the design requirement.
And 3, excavating the tunnel step by step after the advance support is completely constructed, and sealing the tunnel in time after the excavation to construct a flexible primary support (support opportunity (2)). The railway tunnel of the embodiment adopts a primary support scheme of a system anchor rod, sprayed concrete and a steel arch frame. The strength of the sprayed concrete is C25, and the thickness is 27cm; the system anchor rod of the arch part is 3.5m long
Combining hollow anchor rods; the side wall is 3.5m long
A mortar anchor rod; the inverted arch is 5m long
Mortar anchor rods, wherein the distance between the anchor rods of the system is 1.2m multiplied by 1.0m; the section steel arch frame adopts I20b section steel, and the distance between the arch frames is 0.6m. The flexible primary support is used after the tunnel is excavated, so that the surrounding rock is allowed to release certain deformation in a high ground stress environment, the deformation energy accumulated in the surrounding rock can be fully released, and the control concept of 'first yielding' is met. The flexible primary support types comprise low-rigidity primary support, a retractable steel frame, a compressible buffer layer and the like.
In step 4, when the deformation u is accumulated>50％u 1 When the deformation rate v has no obvious convergence trend (v is not equal to 0), reinforcing surrounding rocks behind the primary support by adopting an active support method in the support opportunity (3); when the cumulative deformation u is 50% 1 If the range is stable, the process goes directly to step 8. In the embodiment, after the tunnel deformation u reaches 40cm, the surrounding rock is actively reinforced by adopting a small-conduit radial grouting method. The small grouting guide pipes are seamless steel pipes with the diameter of 42mm, the wall thickness of 3.5mm and the length of 4.0m, and are arranged in a quincunx shape with the distance of 1.2m multiplied by 1.2m. During specific construction, site lofting of hole sites is performed, a rock drill is used for drilling, after drilling is completed, the holes are cleaned, hammering is performed, a small grouting guide pipe is driven, grouting materials are cement paste with a water cement ratio of 0.8. And grouting the vault surrounding rock from the side walls on the two sides in sequence and finally grouting the vault surrounding rock. When the grouting pressure reaches the design pressure, the grouting amount reaches the design value, and the grouting can be stopped when the grouting amount is not fed or is small.
Step 5, when the accumulated deformation u continuously increases to u>75％u 1 When the deformation rate v has no obvious convergence trend (v is not equal to 0), improving the primary support rigidity by adopting a passive support method at the support time (4) to control the deformation of the surrounding rock; when the cumulative deformation u is 75% 1 If the range is stable, the process goes directly to step 8. In the embodiment, after the tunnel deformation u reaches 60cm, the deformation of the surrounding rock is controlled by adopting a method of additionally arranging a second layer of steel arch. The second layer of steel arch frames are made of I22b type steel, and the distance between the arch frames is 0.6m. During specific construction, the arch frame is arranged on the inverted arch with the strength meeting the requirement, and the steel arch frames are arranged between the steel arch framesPhi 22 steel bars are connected into a whole, and the circumferential distance between the steel bars is 0.6-0.8 m. 4-6 foot-locking anchor pipes with phi 42 and L =4.5m are respectively arranged on the arch foot of each arch frame, the front end of each anchor pipe is provided with a grout overflow hole, and the anchor pipes and the peripheral rock strata are consolidated by grouting into the foot-locking anchor pipes so as to ensure that the arch frames do not sink and slide. The gap between the arch frame and the primary support surface is tightly wedged by wood wedges or other objects to ensure that the arch protection is completely stressed.
Step 6, when the accumulated deformation u is still continuously increased to exceed the reserved deformation u>u 1 After the deformation is stable (v = 0), removing the limit-invasion primary support and expanding and excavating the section of the tunnel at the time (5), and increasing the reserved deformation amount to u 2 Applying a reinforced primary support; when the accumulated deformation u is in the reserved deformation range u 1 If the stability is reached, the process proceeds to step 8. The deformation of the surrounding rock of the embodiment is mostly controlled under the supporting action of the second-layer steel arch, but the primary supporting deformation of partial cross section exceeds the reserved deformation. For the section, firstly, the original primary support sprayed concrete is broken and the original primary support steel arch is removed according to the principle of 'removing and changing one by one and stably controlling deformation'. Then, manually expanding and digging to the designed contour line by using tools such as an air pick and the like, trimming the excavated section, and increasing the reserved deformation to u 2 =90cm, the clearance size of the cross section should be checked repeatedly before arch replacement is carried out; after expanding and digging, the concrete is sprayed to close the rock surface, then the reinforced new arch frame is replaced, and the locking anchor pipe is constructed quickly. When the deformation still exceeds the reserved deformation u in the third stage 1 Removing the primary support of the invasion limit, enlarging the tunnel section, and increasing the reserved deformation to u 2 And applying comprehensive control measures for strengthening the primary support. The primary support is reinforced by increasing the thickness of concrete, selecting high-rigidity steel arch frames, reducing the space between the steel arch frames, additionally arranging a locking leg pipe shed and the like.
The reinforcing primary support of the embodiment adopts I22b section steel, the distance between the arches is 0.6m, the steel arches are connected into a whole by phi 22 steel bars, the circumferential distance between the steel bars is 0.6-0.8 m, 4-6 phi 42 locking anchor pipes are adopted, and L =4.5m. And finally, after the erection of the steel arch frame is finished, spraying C25 concrete again to the designed thickness, and thickening the sprayed concrete to 30cm, thereby finishing the dismounting and replacement of the primary support.
7, repeating the step 4 to the step 6 until the final accumulated deformation u of the primary support is controlled within the reserved deformation range;
and 8, constructing a secondary lining of the tunnel, and performing tunnel excavation support of the next cycle.
Claims (5)
1. A dynamic grading control method for large deformation of a high-ground-stress deep-buried soft rock tunnel is characterized by comprising the following steps:
s1, according to the strength-stress ratio of surrounding rockR c /P 0 Relative deformation of tunnelε And relative rate of deformationη Determining the large deformation grade of the tunnel, and drawing up the reserved deformation of the tunnel according to the large deformation grade of the tunnelu 1 ；P 0 The ground stress of the tunnel construction face position is obtained;R c the saturated uniaxial compressive strength of the surrounding rock; relative deformation of tunnelεThe calculation formula of (c) is:
(ii) a Wherein,R 0 is the equivalent radius of the tunnel;u 0 the maximum deformation of the constructed tunnel section is obtained; relative rate of deformationηThe calculation formula of (c) is:
(ii) a Wherein,v 0 the maximum deformation rate of the constructed large deformation section tunnel is obtained;R 0 is the equivalent radius of the tunnel;
s2, relative deformation rate of tunnelη > 0.8%·d -1 When the surrounding rock in front of the tunnel face needs to be actively reinforced by adopting advance support, and the step S3 is carried out; when relative rate of deformationη < 0.8%·d -1 If yes, directly entering step S3; d represents the unit "day";
s3, judging that the tunnel is excavated step by step in a step manner, and sealing the tunnel to form a ring to construct a flexible primary support;
s4, when the deformation is accumulateduGreater than the first warning value and the deformation rate vWhen not equal to 0, judging that surrounding rocks behind the primary support need to be reinforced by adopting an active support method; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
when the deformation is accumulateduContinuously increasing to be larger than a second early warning value, and the deformation ratevWhen not equal to 0, judging that the deformation of the surrounding rock is controlled by improving the primary support rigidity by adopting a passive support method; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
when the deformation is accumulateduContinues to grow to exceed the reserved deformationu 1 Then wait forvAfter =0, the tunnel section needs to be demolished and excavated, and the reserved deformation is increased to the extent thatu 2 Applying a reinforced primary support; otherwise, judging to construct a tunnel secondary lining, and performing tunnel excavation supporting of the next cycle;
s5, repeating the step S4 until the final accumulated deformation of the primary supportuControlled within a reserved deformation rangeu i Internal;
wherein the first early warning value is less than the second early warning valueu 1 ；
Reserved deformation of tunnelu 1 The determination process of (2) includes:
stress ratio of surrounding rock strengthR c /P 0 And relative deformation of tunnelε Relative rate of deformationηWhen the deformation degree is 0.25 to 0.5, 3 to 5 and 0.3 to 0.5 respectively, determining that the large deformation grade of the tunnel is I grade, and the corresponding reserved deformation amount is 20 to 30cm;
stress ratio of surrounding rock strengthR c /P 0 Relative deformation of tunnelε Relative rate of deformationηWhen the deformation degree is 0.15 to 0.25, 5 to 8 and 0.5 to 0.8 respectively, determining that the large deformation grade of the tunnel is II grade, and the corresponding reserved deformation amount is 40 to 50cm;
stress ratio of surrounding rock strength
Relative deformation of tunnelε>8. Relative rate of deformationη>And when 0.8, determining that the large deformation grade of the tunnel is III grade, and the corresponding reserved deformation amount is 50-80 cm.
2. The dynamic grading control method for large deformation of the high-ground-stress deep-buried soft rock tunnel according to claim 1, wherein the first early warning value is set to 50% u 1 (ii) a The second early warning value is set to be 75 percent u 1 。
3. A computer system comprising a memory, a processor, and a computer program stored on the memory; characterized in that the processor executes the computer program to implement the steps of the method of claim 1 or 2.
4. A computer program product comprising a computer program/instructions; characterized in that the computer program/instructions, when executed by a processor, carries out the steps of the method of claim 1 or 2.
5. A computer readable storage medium having stored thereon a computer program/instructions; characterized in that the computer program/instructions, when executed by a processor, implement the steps of the method of claim 1 or 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111628550.4A CN114352358B (en) | 2021-12-28 | 2021-12-28 | Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111628550.4A CN114352358B (en) | 2021-12-28 | 2021-12-28 | Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114352358A CN114352358A (en) | 2022-04-15 |
| CN114352358B true CN114352358B (en) | 2022-12-02 |
Family
ID=81103441
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111628550.4A Active CN114352358B (en) | 2021-12-28 | 2021-12-28 | Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114352358B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115163125B (en) * | 2022-07-29 | 2024-05-14 | 中南大学 | Differential grading control method and system suitable for asymmetric extrusion soft rock tunnel |
| CN116357347B (en) * | 2023-03-31 | 2024-02-02 | 重庆建工集团股份有限公司 | Control method for large deformation surrounding rock of tunnel high-ground-stress soft rock |
| CN116992545B (en) * | 2023-09-04 | 2024-08-02 | 北京交通大学 | Large deformation grading method for ultra-high ground stress ultra-large buried depth soft rock tunnel |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201241712Y (en) * | 2008-08-22 | 2009-05-20 | 中铁第一勘察设计院集团有限公司 | Primary support structure of large deformation formation tunnel |
| JP2011256525A (en) * | 2010-06-04 | 2011-12-22 | Ohbayashi Corp | Tunnel monitoring method |
| CN110847930A (en) * | 2019-12-09 | 2020-02-28 | 中交第一公路勘察设计研究院有限公司 | Multistage yielding-resisting supporting structure of extremely-high ground stress soft rock large-deformation tunnel and construction method |
| JP6804606B1 (en) * | 2019-09-25 | 2020-12-23 | 大成建設株式会社 | Tunnel support building equipment |
| CN112196582A (en) * | 2020-10-15 | 2021-01-08 | 中铁二局第二工程有限公司 | Method for controlling severe deformation of strong-earthquake deep-buried soft rock stratum tunnel |
| WO2021169336A1 (en) * | 2020-02-25 | 2021-09-02 | 山东大学 | Near-field dynamics method and system for simulating sudden inrush water disaster of tunnel rock mass failure |
-
2021
- 2021-12-28 CN CN202111628550.4A patent/CN114352358B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201241712Y (en) * | 2008-08-22 | 2009-05-20 | 中铁第一勘察设计院集团有限公司 | Primary support structure of large deformation formation tunnel |
| JP2011256525A (en) * | 2010-06-04 | 2011-12-22 | Ohbayashi Corp | Tunnel monitoring method |
| JP6804606B1 (en) * | 2019-09-25 | 2020-12-23 | 大成建設株式会社 | Tunnel support building equipment |
| CN110847930A (en) * | 2019-12-09 | 2020-02-28 | 中交第一公路勘察设计研究院有限公司 | Multistage yielding-resisting supporting structure of extremely-high ground stress soft rock large-deformation tunnel and construction method |
| WO2021169336A1 (en) * | 2020-02-25 | 2021-09-02 | 山东大学 | Near-field dynamics method and system for simulating sudden inrush water disaster of tunnel rock mass failure |
| CN112196582A (en) * | 2020-10-15 | 2021-01-08 | 中铁二局第二工程有限公司 | Method for controlling severe deformation of strong-earthquake deep-buried soft rock stratum tunnel |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114352358A (en) | 2022-04-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114352358B (en) | Dynamic grading control method and system for large deformation of high-ground-stress deep-buried soft rock tunnel | |
| CN101614125B (en) | Construction method of V-level surrounding rock tunnel | |
| CN102042019B (en) | Two-stair five-step excavation construction method for shallow-buried large-span soft plastic clay tunnel | |
| CN102134998B (en) | Construction method for wind-blown sand tunnel | |
| CN203547773U (en) | Channel combined support structure suitable for slowly inclined stratified rock mass | |
| CN102926757A (en) | Construction method of two-sidestep and four-step excavation support of weak large-span tunnel of mountain ridge | |
| CN102660955B (en) | Quick construction method for foundation pit slope support | |
| CN104533446A (en) | Construction method and structure of two-layer preliminary support for preventing geological disaster of large-section weak surrounding rock tunnel | |
| CN111502696A (en) | Dense-mesh type advanced support system of underground excavation tunnel and construction method | |
| CN108412519A (en) | The slight large deformation single-track tunnel suspension device of highlands soft rock and construction method | |
| CN104632249A (en) | Tunnel system supporting technology used in loose and soft broken surrounding rock | |
| CN104141500B (en) | One hardens sand and gravel stratum cavern con struction method | |
| CN109695457A (en) | In-situ expansion super-large section tunnel of hard rock and step construction method | |
| CN217419613U (en) | Protection structure for excavating and unloading existing underground structure | |
| CN101215840A (en) | Airplane type foundation reinforcing and prestressing method | |
| CN102002942A (en) | Hollow drilling pile and piling construction process for steel tube-cement soil composite pile | |
| CN116752977A (en) | Advanced pre-supporting method for tunnel construction pipe shed by mine method | |
| CN114622574B (en) | Water-rich throwing filling deep foundation pit water interception excavation supporting method and supporting device | |
| CN107794927B (en) | Deep foundation pit earthwork excavation method with hard rock geology | |
| CN111911169B (en) | Construction method and structure of shallow buried depth tunnel under existing railway line | |
| CN114876469A (en) | High-speed super-large section tunnel excavation construction method | |
| CN210180295U (en) | Blasting construction structure | |
| CN109653193B (en) | Reverse construction method for underground continuous wall | |
| CN100593052C (en) | Open cut foundation pit supporting and protecting method | |
| CN221703742U (en) | Construction supporting structure for preventing primary support from sinking, converging and deforming of weak surrounding rock of tunnel |
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 |