CN113536445A - Simple determination method for tunnel longitudinal upward floating deformation caused by excavation of upper foundation pit - Google Patents
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Abstract
The invention particularly relates to a simple determination method for tunnel longitudinal upward floating deformation caused by excavation of an upper foundation pit, which comprises the following steps: step 1, determining geometrical information of an upper foundation pit, geometrical information and geological information of an existing tunnel; step 2, calculating the vertical additional load of the existing tunnel caused by excavation of the foundation pit above; when the existing tunnel is not located under the foundation pit and/or the existing tunnel is obliquely crossed with the foundation pit, correcting the vertical additional load of the existing tunnel; step 3, calculating the vertical displacement of the existing tunnel caused by excavation of the foundation pit above; and 4, calculating the longitudinal differential settlement of the existing tunnel and the longitudinal curvature of the existing tunnel caused by excavation of the foundation pit above. The simple method for determining the longitudinal upward floating deformation of the tunnel caused by the excavation of the upper foundation pit can predict the longitudinal deformation distribution of the existing subway tunnel caused by the excavation of the upper foundation pit, so that a guidance suggestion can be provided for the design of the excavation of the upper foundation pit, and the method is simple, practical and convenient to apply and popularize.
Description
Technical Field
The invention relates to the technical field of constructional engineering, in particular to a simple determination method for tunnel longitudinal upward floating deformation caused by excavation of an upper foundation pit.
Background
Along with the continuous development of urban underground space in China, projects for newly building foundation pits above the existing underground rail transit structure are increased gradually. The underground tunnel structure is generally weaker in rigidity in the longitudinal direction, upward floating deformation easily occurs under the unloading action of upper soil body excavation, and when the underground tunnel structure is serious, diseases such as opening of segment joints, platform staggering, water leakage, cracking, block falling and the like can occur, so that the normal operation of the underground track traffic structure is influenced. The requirement of the underground rail transit structure on deformation is strict. Such as the industry standard of the people's republic of China: the technical specification for the safety protection of urban rail transit structures, the standard number CJJ/T202-. The early warning value of the vertical deformation of the tunnel specified in the standard is 10 mm, and the control value is 20 mm. In the prior art, the influence of the Wei class foundation pit excavation on the existing shield tunnel below is actually measured and analyzed, the rock-soil mechanics is analyzed, and in 2013(05), 14 examples of foundation pit excavation above the existing subway tunnel in China are counted, and 9 tunnel vertical displacement exceeds an early warning value.
In the prior art, a research method for predicting the longitudinal floating deformation of the existing subway tunnel caused by excavation of an upper foundation pit is mainly a two-stage theoretical analysis method. And calculating additional stress (or displacement) acting on the existing tunnel in the first stage, and calculating deformation and internal force of the existing tunnel through a tunnel-soil interaction model in the second stage. In the prior art [2] the present invention relates to a method for evaluating the effects of shield excavation on shield tunnel construction, and particularly relates to a method for analyzing the effects of shield excavation on shield tunnel construction, which is based on a Simplified analysis method for analyzing the effects of shield excavation under shear effect, and which is based on a Simplified analysis method for analyzing the shield excavation effects under shield excavation by using a minimum elastic solution. Although the concept of the theoretical analysis method is clear, the solving process is relatively complex, and corresponding calculation programs need to be written aiming at different working conditions, so that the theoretical analysis method is not beneficial to direct adoption by construction and designers.
Therefore, in order to solve the problem of floating deformation of the existing tunnel caused by excavation of the upper foundation pit, a simple method for determining longitudinal floating deformation of the tunnel caused by excavation of the upper foundation pit needs to be provided.
Disclosure of Invention
The invention provides a simple method for determining the longitudinal upward floating deformation of a tunnel caused by the excavation of an upper foundation pit, which can predict the longitudinal deformation distribution of the existing subway tunnel caused by the excavation of the upper foundation pit, thereby providing a guidance suggestion for the design of the excavation of the upper foundation pit. Therefore, the defects of long time consumption of a finite element method and complex calculation process of a theoretical method are overcome.
A simple determination method for tunnel longitudinal upward floating deformation caused by excavation of an upper foundation pit specifically comprises the following steps:
step 1, determining geometrical information of an upper foundation pit, geometrical information and geological information of an existing tunnel;
the geometrical information of the upper foundation pit comprises: excavation length of foundation pitL，Excavation depth of foundation pitH，Width of excavation of foundation pitB；
The existing tunnel geometry information comprises: tunnel axis burial depthhOuter diameter D of shield tunnel, horizontal distance between tunnel axis and center line of foundation pitdThe included angle between the tunnel axis and the excavation length direction of the foundation pitα；
The geological information comprises: the stratum gravity and the vertical bed coefficient of the stratum where the existing tunnel is located;
step 3, calculating the vertical displacement of the existing tunnel caused by excavation of the foundation pit above;
and 4, calculating the longitudinal differential settlement of the existing tunnel and the longitudinal curvature of the existing tunnel caused by excavation of the foundation pit above.
Further, the step 2 comprises:
step 2.1, calculating the load factorFAnd according to the load factorFJudging the distribution form of the vertical additional load of the existing tunnel caused by excavation of the foundation pit above; load factorFThe expression of (a) is:
F=h-kL-1.2H （1）
k=0.065ln(B/H)+0.112 （2）
wherein,hburying depth for the tunnel axis;Lexcavating length for the foundation pit;Hexcavating depth for the foundation pit;Bthe width of the excavation for the foundation pit is wide,kis aboutBAndHthe coefficient of (a).
Further, the step 2 further comprises:
step 2.2, whenFWhen the load is more than or equal to 0, the vertical additional load of the existing tunnel follows Gaussian curve distribution, and the calculation formula is as follows:
wherein q (x) is the vertical additional load of the existing tunnel,xin order to be the longitudinal length of the tunnel,q maxthe maximum value of the vertical additional load of the existing tunnel;
the maximum value of the vertical additional load of the existing tunnel is dimensionless;i q adding a load width parameter for the existing tunnel in the longitudinal direction;
adding a load width parameter for the existing tunnel in a non-dimensionalization mode;β s for the aspect ratio impact coefficient of the foundation pit,β s =1-0.05(L/B-1)；γ s is the formation severity;Dis the outer diameter of the shield tunnel.
Further, the step 2 further comprises:
step 2.3, whenFAnd when the vertical load of the existing tunnel generated by each segmented foundation pit is less than 0, performing segmented calculation in the length direction of the foundation pit excavation, so that the vertical additional load of the existing tunnel caused by each segmented foundation pit excavation follows Gaussian curve distribution, calculating the vertical additional load of the existing tunnel generated by each segmented foundation pit, further calculating the vertical displacement of the existing tunnel generated by each segmented foundation pit, and obtaining the overall vertical displacement of the existing tunnel after superposition.
Further, the step 2 further comprises:
when the existing tunnel is not positioned under the foundation pit and/or the existing tunnel is obliquely crossed with the foundation pit, the horizontal distance between the axis of the tunnel and the central line of the foundation pit is considereddAnd the included angle between the existing tunnel axis and the length direction of the foundation pitαInfluence of (2) on maximum value of vertical additional load of existing tunnelq maxAnd the width parameter of the longitudinal additional load of the existing tunneli q And (4) correcting, and calculating a formula:
q kmax=β d q max （6）
i qk =λ d λ α i q （7）
wherein,q kmaxthe corrected vertical maximum additional load of the existing tunnel;i qk adding a load width parameter for the corrected existing tunnel longitudinally;β d the correction coefficient is the maximum vertical additional load of the existing tunnel under the eccentric condition;λ d the correction coefficient of the additional load width of the existing tunnel under the eccentric condition;λ α and the correction coefficient of the additional load width of the existing tunnel under the condition of skew.
Further, the calculation formula of the vertical displacement of the existing tunnel in the step 3 is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,w(x) In order to make the existing tunnel vertically displace,xis the longitudinal length of the tunnel;i w the vertical displacement width of the existing tunnel;f w the maximum vertical displacement coefficient of the existing tunnel;k v the coefficient of the vertical foundation bed is shown as,q kmaxthe corrected maximum vertical additional load of the existing tunnel.
Further, in the step 4
The calculation formula of the existing tunnel longitudinal differential settlement is as follows:
the calculation formula of the longitudinal curvature of the existing tunnel is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,i w the vertical displacement width of the existing tunnel is wide.
The invention has the following beneficial effects:
1. the method can predict the longitudinal deformation distribution of the existing subway tunnel caused by excavation of the upper foundation pit;
2. the invention provides a simple and convenient calculation method aiming at the problem of floating deformation of the existing tunnel caused by excavation of the foundation pit above, and the method is simple, practical and convenient to apply and popularize.
3. The invention makes up the defects of long time consumption of a finite element method and complex calculation process of a theoretical method.
Drawings
FIG. 1 is a schematic diagram of a position relationship between an existing tunnel and an upper foundation pit in the invention;
FIG. 2 is a side view of the existing tunnel in relation to the foundation pit above in the present invention;
FIG. 3 is a top view of the existing tunnel in relation to the position of the foundation pit above it in accordance with the present invention;
FIG. 4 is a schematic diagram illustrating the calculation of vertical displacement of an existing tunnel by upper foundation pit segments;
fig. 5 is a vertical displacement curve of an existing tunnel in embodiment 2 of the present invention;
FIG. 6 is a differential settlement curve of the existing tunnel in example 2 of the present invention;
fig. 7 is a longitudinal curvature curve of an existing tunnel in example 2 of the present invention.
Detailed Description
It should be apparent that the embodiments described below are some, but not all embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it is to be noted that the terms "mounted," "connected," and "connected" are to be construed broadly unless otherwise specifically indicated and limited.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Example 1
A simple determination method for tunnel longitudinal upward floating deformation caused by excavation of an upper foundation pit specifically comprises the following steps:
step 1, determining geometrical information of an upper foundation pit, geometrical information and geological information of an existing tunnel;
the geometrical information of the upper foundation pit comprises: excavation length of foundation pitL，Excavation depth of foundation pitH，Width of excavation of foundation pitB；
The existing tunnel geometry information comprises: tunnel axis burial depthhOuter diameter D of shield tunnel, horizontal distance between tunnel axis and center line of foundation pitdThe included angle between the tunnel axis and the excavation length direction of the foundation pitα；
The geological information comprises: the stratum gravity and the vertical bed coefficient of the stratum where the existing tunnel is located;
step 3, calculating the vertical displacement of the existing tunnel caused by excavation of the foundation pit above;
and 4, calculating the longitudinal differential settlement of the existing tunnel and the longitudinal curvature of the existing tunnel caused by excavation of the foundation pit above.
The step 2 comprises the following steps:
step 2.1, calculating the load factorFAnd according to the load factorFJudging the distribution form of the vertical additional load of the existing tunnel caused by excavation of the foundation pit above; load factorFThe expression of (a) is:
F=h-kL-1.2H （1）
k=0.065ln(B/H)+0.112 （2）
wherein,hburying depth for the tunnel axis;Lexcavating length for the foundation pit;Hexcavating depth for the foundation pit;Bthe width of the excavation for the foundation pit is wide,kis aboutBAndHthe coefficient of (a).
The step 2 further comprises:
step 2.2, whenFWhen the load is more than or equal to 0, the vertical additional load of the existing tunnel follows Gaussian curve distribution, and the calculation formula is as follows:
wherein q (x) is the vertical additional load of the existing tunnel,xin order to be the longitudinal length of the tunnel,q maxthe maximum value of the vertical additional load of the existing tunnel;
the maximum value of the vertical additional load of the existing tunnel in the dimensionless mode can be determined according to parametersLB/H 2Andh/Hlooking up a table 1 to obtain;i q adding a load width parameter for the existing tunnel in the longitudinal direction;
for dimensionless existing tunnelsLongitudinal additional load width parameter, according to whichL/BAndh/Hlooking up a table 2 to obtain;β s for the aspect ratio impact coefficient of the foundation pit,β s =1-0.05(L/B-1)；γ s is the formation severity;Dis the outer diameter of the shield tunnel.
The step 2 further comprises:
step 2.3, whenFAnd when the vertical load of the existing tunnel generated by each segmented foundation pit is less than 0, performing segmented calculation in the length direction of the foundation pit excavation, so that the vertical additional load of the existing tunnel caused by each segmented foundation pit excavation follows Gaussian curve distribution, calculating the vertical additional load of the existing tunnel generated by each segmented foundation pit, further calculating the vertical displacement of the existing tunnel generated by each segmented foundation pit, and obtaining the overall vertical displacement of the existing tunnel after superposition.
The step 2 further comprises:
when the existing tunnel is not positioned under the foundation pit and/or the existing tunnel is obliquely crossed with the foundation pit, the horizontal distance between the axis of the tunnel and the central line of the foundation pit is considereddAnd the included angle between the existing tunnel axis and the length direction of the foundation pitαInfluence of (2) on maximum value of vertical additional load of existing tunnelq maxAnd the width parameter of the longitudinal additional load of the existing tunneli q And (4) correcting, and calculating a formula:
q kmax=β d q max （6）
i qk =λ d λ α i q （7）
wherein,q kmaxthe corrected vertical maximum additional load of the existing tunnel;i qk adding the load width to the corrected existing tunnel;β d the correction coefficient of the vertical maximum additional load of the existing tunnel under the eccentric condition can be obtained according to the parametersd/BAndh/Hlooking up a table 3 to obtain;λ d the correction coefficient of the additional load width of the existing tunnel under the eccentric condition can be obtained according to the parametersd/BAndh/Hlooking up a table 4 to obtain;λ α the correction coefficient of the additional load width of the existing tunnel under the condition of skew can be obtained according to the parametersL/BAndαthe look-up table 5 is obtained.
The calculation formula of the vertical displacement of the existing tunnel in the step 3 is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,w(x) In order to make the existing tunnel vertically displace,xis the longitudinal length of the tunnel;i w for the existing tunnel vertical displacement width, the vertical displacement width can be changed according to parametersk v Andi qk looking up a table 6-1, a table 6-2 and a table 6-3;f w the maximum vertical displacement coefficient of the existing tunnel can be obtained according to the parametersk v Andi qk table look-up 7-1, table 7-2 and table 7-3;k v the coefficient of the vertical foundation bed is shown as,q kmaxthe corrected maximum vertical additional load of the existing tunnel.
In said step 4
The calculation formula of the existing tunnel longitudinal differential settlement is as follows:
the calculation formula of the longitudinal curvature of the existing tunnel is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,i w the vertical displacement width of the existing tunnel.
TABLE 1 vertical maximum additional load coefficient of existing tunnel caused by excavation of foundation pit above
TABLE 2 vertical additional load width coefficient of existing tunnel caused by excavation of foundation pit above
TABLE 3 correction coefficient of vertical maximum additional load of existing tunnel under eccentric condition
TABLE 4 correction coefficient of vertical additional load width of existing tunnel under eccentric condition
TABLE 5 correction coefficient of additional load width parameter of tunnel structure under skew condition
TABLE 6-1 existing Tunnel vertical Displacement Width first portion
TABLE 6-2 second part of existing Tunnel vertical Displacement Width
TABLE 6-3 vertical Displacement Width third portion of existing Tunnel
TABLE 7-1 maximum vertical Displacement coefficient first part of existing Tunnel
TABLE 7-2 second part of maximum vertical Displacement coefficient of existing Tunnel
TABLE 7-3 maximum vertical Displacement coefficient third portion of existing Tunnel
Example 2
This example provides a specific case using the method mentioned in example 1.
The method comprises the following steps of firstly, determining the geometric information of the foundation pit above, the geometric information of the existing tunnel and the geological information.
The excavation length of the foundation pit selected in this caseL26m, width of excavation of foundation pitB18m, excavation depth of foundation pitHIs 8 m. Outer diameter of shield tunnelD6.2m, tunnel axis buried depthhIs 15 m. Stratum gravity of foundation pit excavationγ s Is 18kN/m3Horizontal distance between tunnel axis and center line of foundation pitdIs 4m, and the included angle between the tunnel axis and the excavation length direction of the foundation pitαIs 15 deg.. The coefficient of the vertical bed of the stratum where the existing tunnel is located is 2 multiplied by 104kN/m2。
And secondly, calculating the vertical additional load of the existing tunnel caused by excavation of the foundation pit above.
According toCalculating to obtain a load factor according to the formulas (1) and (2)F=1.12。FAnd if the load is larger than 0, indicating that the vertical additional load of the existing tunnel caused by excavation of the foundation pit above follows Gaussian distribution. By looking up the table 1, the maximum value of the vertical additional load of the existing tunnel without dimensionalization can be obtained
Is 0.60; by looking up the table 2, the non-dimensionalized longitudinal additional load width parameter of the existing tunnel can be obtained
Is 1.42. Calculating according to a formula (4) to obtain the maximum value of the vertical additional load of the existing tunnelq max523.77 kN/m; calculating to obtain the longitudinal additional load width of the existing tunnel according to the formula (5)i q And was 11.36 m.
And thirdly, correcting the vertical additional load of the existing tunnel by considering the complex position relationship between the upper foundation pit and the existing tunnel.
By looking up the table 3, the correction coefficient of the vertical maximum additional load of the existing tunnel under the eccentric condition can be obtainedβ d Is 0.96; by looking up the table 4, the correction coefficient of the vertical maximum additional load width of the existing tunnel under the eccentric condition can be obtainedλ d Is 1.15; by looking up the table 5, the correction coefficient of the additional load width of the existing tunnel under the condition of skew intersection can be obtainedλ d Is 0.99. Calculating and obtaining the corrected vertical maximum additional load of the existing tunnel according to the formula (6)q kmax502.82 kN/m; calculating and obtaining the corrected vertical maximum additional load of the existing tunnel according to a formula (7)i qk And was 12.93 m.
And fourthly, calculating the vertical displacement of the existing tunnel caused by excavation of the foundation pit above.
The vertical displacement width of the existing tunnel can be obtained by looking up the table 6-1, the table 6-2 and the table 6-3i w Is 15.25 m; the maximum vertical displacement coefficient of the existing tunnel can be obtained by looking up tables 7-1, 7-2 and 7-3f w Is 0.86; according to the formula (9) Calculating to obtain the maximum value of the vertical displacement of the existing tunnelw maxAnd 21.62 mm. And (5) calculating according to a formula (8) to obtain a vertical displacement curve of the existing tunnel, as shown in fig. 5.
And fifthly, calculating the longitudinal differential settlement and curvature of the existing tunnel caused by excavation of the foundation pit above.
And (4) calculating to obtain a longitudinal differential settlement curve of the existing tunnel according to the formula (10), as shown in fig. 6. The existing tunnel longitudinal curvature curve is calculated according to the formula (11), as shown in fig. 7.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (7)
1. A simple method for determining the longitudinal upward floating deformation of a tunnel caused by excavation of an upper foundation pit is characterized by comprising the following steps:
step 1, determining geometrical information of an upper foundation pit, geometrical information and geological information of an existing tunnel;
the geometrical information of the upper foundation pit comprises: excavation length of foundation pitL，Excavation depth of foundation pitH，Width of excavation of foundation pitB；
The existing tunnel geometry information comprises: tunnel axis burial depthhOuter diameter D of shield tunnel, horizontal distance between tunnel axis and center line of foundation pitdThe included angle between the tunnel axis and the excavation length direction of the foundation pitα；
The geological information comprises: the stratum gravity and the vertical bed coefficient of the stratum where the existing tunnel is located;
step 2, calculating the vertical additional load of the existing tunnel caused by excavation of the foundation pit above; when the existing tunnel is not located under the foundation pit and/or the existing tunnel is obliquely crossed with the foundation pit, correcting the vertical additional load of the existing tunnel;
step 3, calculating the vertical displacement of the existing tunnel caused by excavation of the foundation pit above;
and 4, calculating the longitudinal differential settlement of the existing tunnel and the longitudinal curvature of the existing tunnel caused by excavation of the foundation pit above.
2. The method for easily determining the vertical uplift deformation of the tunnel caused by excavation of the foundation pit above according to claim 1, wherein the step 2 comprises the following steps:
step 2.1, calculating the load factorFAnd according to the load factorFJudging the distribution form of the vertical additional load of the existing tunnel caused by excavation of the foundation pit above; load factorFThe expression of (a) is:
F=h-kL-1.2H （1）
k=0.065ln(B/H)+0.112 （2）
wherein,hburying depth for the tunnel axis;Lexcavating length for the foundation pit;Hexcavating depth for the foundation pit;Bthe width of the excavation for the foundation pit is wide,kis aboutBAndHthe coefficient of (a).
3. The method for easily determining the vertical uplift deformation of the tunnel caused by excavation of the foundation pit above according to claim 2, wherein the step 2 further comprises:
step 2.2, whenFWhen the load is more than or equal to 0, the vertical additional load of the existing tunnel follows Gaussian curve distribution, and the calculation formula is as follows:
wherein q (x) is the vertical additional load of the existing tunnel,xin order to be the longitudinal length of the tunnel,q maxthe maximum value of the vertical additional load of the existing tunnel;
the maximum value of the vertical additional load of the existing tunnel is dimensionless;i q adding a load width parameter for the existing tunnel in the longitudinal direction;
adding a load width parameter for the existing tunnel in a non-dimensionalization mode;β s for the aspect ratio impact coefficient of the foundation pit,β s =1-0.05(L/B-1)；γ s is the formation severity;Dis the outer diameter of the shield tunnel.
4. The method for easily determining the vertical uplift deformation of the tunnel caused by excavation of the foundation pit above according to claim 3, wherein the step 2 further comprises:
step 2.3, whenFAnd when the vertical load of the existing tunnel generated by each segmented foundation pit is less than 0, performing segmented calculation in the length direction of the foundation pit excavation, so that the vertical additional load of the existing tunnel caused by each segmented foundation pit excavation follows Gaussian curve distribution, calculating the vertical additional load of the existing tunnel generated by each segmented foundation pit, further calculating the vertical displacement of the existing tunnel generated by each segmented foundation pit, and obtaining the overall vertical displacement of the existing tunnel after superposition.
5. The method for easily determining the vertical uplift deformation of the tunnel caused by excavation of the foundation pit above according to claim 3, wherein the step 2 further comprises:
when the existing tunnel is not positioned under the foundation pit and/or the existing tunnel is obliquely crossed with the foundation pit, the maximum value of the vertical additional load of the existing tunnelq maxAnd the longitudinal additional load width of the existing tunnelDegree parameteri q And (4) correcting, and calculating a formula:
q kmax=β d q max （6）
i qk =λ d λ α i q （7）
wherein,q kmaxthe corrected vertical maximum additional load of the existing tunnel;i qk adding a load width parameter for the corrected existing tunnel longitudinally;β d the correction coefficient is the maximum vertical additional load of the existing tunnel under the eccentric condition;λ d the correction coefficient of the additional load width of the existing tunnel under the eccentric condition;λ α and the correction coefficient of the additional load width of the existing tunnel under the condition of skew.
6. The simple method for determining the vertical upward floating deformation of the tunnel caused by excavation of the upper foundation pit as claimed in claim 5, wherein the calculation formula of the vertical displacement of the existing tunnel in the step 3 is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,w(x) In order to make the existing tunnel vertically displace,xis the longitudinal length of the tunnel;i w the vertical displacement width of the existing tunnel;f w the maximum vertical displacement coefficient of the existing tunnel;k v the coefficient of the vertical foundation bed is shown as,q kmaxthe corrected maximum vertical additional load of the existing tunnel.
7. The method for easily determining the vertical uplift deformation of the tunnel caused by excavation of the foundation pit above according to claim 6, wherein the step 4 is carried out
The calculation formula of the existing tunnel longitudinal differential settlement is as follows:
the calculation formula of the longitudinal curvature of the existing tunnel is as follows:
wherein,w maxis the maximum value of the vertical displacement of the existing tunnel,i w the vertical displacement width of the existing tunnel.
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| CN105220718A (en) * | 2015-10-26 | 2016-01-06 | 青岛理工大学 | Method for pre-determining influence of building construction on adjacent existing tunnel |
| CN106339554A (en) * | 2016-08-29 | 2017-01-18 | 浙江大学城市学院 | Method for caculating displacement of nearby existing subway tunnel due to foundation pit excavation |
| US20190071968A1 (en) * | 2017-09-05 | 2019-03-07 | Chang'an University | Method for Deformation Control of Large-span Tunnel in Chlorite Schist Stratum |
| CN110727985A (en) * | 2019-09-30 | 2020-01-24 | 天津大学 | Method for predicting vertical deformation of existing subway tunnel adjacent to foundation pit engineering |
| CN112329122A (en) * | 2021-01-07 | 2021-02-05 | 湖南大学 | Method for determining transverse deformation and internal force of shield tunnel caused by excavation of side foundation pit |
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2021
- 2021-09-16 CN CN202111084874.6A patent/CN113536445B/en active Active
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105220718A (en) * | 2015-10-26 | 2016-01-06 | 青岛理工大学 | Method for pre-determining influence of building construction on adjacent existing tunnel |
| CN106339554A (en) * | 2016-08-29 | 2017-01-18 | 浙江大学城市学院 | Method for caculating displacement of nearby existing subway tunnel due to foundation pit excavation |
| US20190071968A1 (en) * | 2017-09-05 | 2019-03-07 | Chang'an University | Method for Deformation Control of Large-span Tunnel in Chlorite Schist Stratum |
| CN110727985A (en) * | 2019-09-30 | 2020-01-24 | 天津大学 | Method for predicting vertical deformation of existing subway tunnel adjacent to foundation pit engineering |
| CN112329122A (en) * | 2021-01-07 | 2021-02-05 | 湖南大学 | Method for determining transverse deformation and internal force of shield tunnel caused by excavation of side foundation pit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116108543A (en) * | 2023-03-15 | 2023-05-12 | 湖南大学 | Method for determining additional internal force and deformation of shield tunnel caused by settlement of under-consolidated stratum |
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