Deep-buried roadway surrounding rock non-probability robustness design method considering parameter dynamic change

Abstract

The invention provides a deep-buried roadway surrounding rock non-probability robustness design method considering dynamic parameter changes, and belongs to the technical field of deep-buried roadway construction. According to the method, the convex set nested model is improved, and the specific representation mode of each uncertainty parameter is quantified to adapt to different fluctuation amplitudes presented by each uncertainty parameter in actual engineering; through a deformation analysis control equation of the deeply-buried roadway surrounding rock, obtaining a performance function describing that the deeply-buried roadway surrounding rock keeps a stable state; establishing a robustness function according to a comparison relationship between an output response value of the performance function and a threshold value of the performance function; defining different maximum fluctuation amplitudes capable of allowing dynamic change of each uncertainty parameter before deformation and instability of the deeply-buried roadway surrounding rock as respective corresponding robust reliability indexes; based on the reasonable selection of support design variables, the change rule of the non-probability robustness of the deeply-buried roadway surrounding rock is analyzed, and a quantitative basis is provided for the judgment of the stability and reliability degree of the deeply-buried roadway surrounding rock.

Description

Technical Field

[0001] The invention belongs to the technical field of deep buried roadway construction, and particularly relates to a non-probabilistic robustness design method for surrounding rock of deep buried roadways considering dynamic parameter changes. Background Art

[0002] In view of the large uncertainty in the stratum occurrence environment of deep buried roadways, the corresponding statistical sample data of uncertainty parameters is seriously lacking. Moreover, as the burial depth of the underground roadway engineering structure in mines continues to increase, it becomes increasingly difficult to obtain sufficient data information related to uncertainty parameters, which usually appears in the form of small samples. Therefore, the traditional probability reliability method that highly relies on a large amount of statistical sample data is no longer applicable in the actual engineering of deep buried roadways, and thus the reliability engineering practical problems begin to be analyzed and processed from a non-probabilistic perspective. Currently, the reliability design method mainly represented by the non-probabilistic robustness theory has received more and more attention. However, the main defect of the existing non-probabilistic robustness design method is that it cannot consider the dynamic changes of various uncertainty parameters in the actual engineering of deep buried roadways, that is: only the same fluctuation amplitude is used to describe the change range of different uncertainty parameters, and it cannot reflect the different fluctuation amplitudes that each uncertainty parameter should present in the actual engineering.

[0003] Therefore, on the basis of the existing non-probabilistic robustness design method, it is necessary to construct a more engineering-actual conforming quantitative processing representation method for each uncertainty parameter to adapt to their respective different fluctuation amplitudes, so as to more reasonably provide a quantitative basis for evaluating the stable and reliable degree of the surrounding rock of deep buried roadways and better serve the construction requirements of the underground roadway engineering structure in mines. Summary of the Invention

[0004] The invention provides a non-probabilistic robustness design method for surrounding rock of deep buried roadways considering dynamic parameter changes. The method starts from improving the convex set nesting model, and conducts quantitative processing on the specific representation methods of each uncertainty parameter to adapt to their respective different fluctuation amplitudes in actual engineering; through the deformation analysis control equation of the surrounding rock of deep buried roadways, a function function describing its stable state is obtained; a robustness function is established based on the comparison relationship between the output response value of the function function and its threshold value; the different maximum fluctuation amplitudes that each uncertainty parameter can allow to change dynamically before the deformation and instability of the surrounding rock of deep buried roadways are defined as their respective corresponding robust reliability indexes; around the reasonable selection of support design variables, the change law of the non-probabilistic robustness of the surrounding rock of deep buried roadways is analyzed, providing a quantitative basis for evaluating its stable and reliable degree, and can effectively solve at least one technical problem involved in the background art.

[0005] In order to solve the above technical problems, the invention is realized as follows:

[0006] A non-probabilistic robust design method for surrounding rock of deep-buried roadway considering dynamic parameter changes, comprising the following steps:

[0007] Step S1, based on the existing non-probabilistic robust design method, quantify the representation of uncertain parameters by improving the convex set nesting model to adapt to the fluctuation range of uncertain parameters;

[0008] Step S2, obtain the performance function describing its stable state through the deformation analysis control equation of the surrounding rock of the deep-buried roadway;

[0009] Step S3, establish a robustness function based on the comparison relationship between the output response value of the performance function and its threshold;

[0010] Step S4, based on the established robustness function, define the maximum fluctuation range of allowable deterministic parameter dynamic changes before the surrounding rock of the deep-buried roadway deforms and becomes unstable as the robust reliability index;

[0011] Step S5, around the reasonable selection of support design variables, use the double-layer convex set nesting optimization method to explore the variation law of non-probabilistic robustness and provide a quantitative basis for evaluating the stability and reliability degree of the surrounding rock of the deep-buried roadway;

[0012] Step S6, verify the non-probabilistic robust design method for the surrounding rock of the deep-buried roadway considering dynamic parameter changes by using the calculation model of the surrounding rock deformation of the deep-buried roadway.

[0013] As a preferred improvement, the uncertain parameters include the internal friction angle of the surrounding rock of the deep-buried roadway cohesion K and deformation modulus E.

[0014] As a preferred improvement, Step S1 specifically includes the following process:

[0015] Based on the existing non-probabilistic robust design method, by improving the convex set nesting model, taking the average value of the uncertain parameters as the nominal value under non-probabilistic conditions, represent the fluctuation range of the uncertain parameters as:

[0016]

[0017] In the formula, u represents the vector set of uncertain parameters; α represents the vector representation of a single uncertain parameter, used to characterize the fluctuation range of the uncertain parameter; c and respectively represent the unknown true value and the known nominal value of a single uncertain parameter; where, α = (α1, α2, α3), α1 represents the vector representation of the internal friction angle α2 represents the vector representation of cohesion K, and α3 represents the vector representation of deformation modulus E; c = (c1, c2, c3), Denote the unknown true value of the internal friction angle as $\varphi$, $c_2 = K$ represents the unknown true value of the cohesion, and $c_3 = E$ represents the unknown true value of the deformation modulus; Denote the known nominal value of the internal friction angle as $\varphi_1$, Denote the known nominal value of the cohesion as $K_1$, Denote the known nominal value of the deformation modulus as $E_1$.

[0018] As a preferred improvement, the deformation analysis control equation of the surrounding rock of the deep-buried roadway is expressed by the ratio of the radial plastic displacement $u$ of the surrounding rock ip to the excavation radius $r_0$, as shown in the following formula:

[0019]

[0020] In the formula, $p_0$ represents the in-situ stress; $p$ s represents the support resistance; $\nu$ represents the Poisson's ratio of the surrounding rock; $p$ cr represents the critical stress; $r$ p represents the radius of the plastic zone of the surrounding rock; where:

[0021]

[0022] $p$ cr $=(2p_0 - \sigma$ cm ) / (k + 1);

[0023]

[0024]

[0025] In the formula, $k$ represents a dimensionless parameter related to the internal friction angle $\varphi$ of the surrounding rock, and $\sigma$ cm represents the uniaxial compressive strength of the surrounding rock;

[0026] Substitute the vector set $u$ of the uncertain parameters into the deformation analysis control equation to obtain the performance function $R(q, u)$ describing the stable state of the surrounding rock, expressed as:

[0027]

[0028] In the formula, $q$ represents the design variable, corresponding to the support resistance $p$ s ; $U$ c represents the threshold value of the surrounding rock deformation control, characterizing the maximum acceptable value corresponding to the performance function $R(q, u)$ when the surrounding rock of the deep-buried roadway does not lose stability in deformation.

[0029] As a preferred improvement, when the internal friction angle $\varphi$, the cohesion $K$ and the deformation modulus $E$ reach their respective maximum offsets from their nominal values to different degrees, it can still ensure that the radial plastic displacement $u$ of the surrounding rock ipIf the maximum acceptable value of the ratio to the excavation radius \(r_0\) satisfies the performance function \(R(q, u)\), then the robustness function can be obtained, which is expressed as:

[0030]

[0031] In the formula, is the robust reliability index, which is a function of the vector \(\alpha\) and represents the different maximum fluctuation ranges that the uncertainty parameters can dynamically change before the surrounding rock deformation becomes unstable.

[0032] As a preferred improvement, step S5 specifically includes the following process:

[0033] For the solution of in the robustness function, during the calculation, first assume that \(\alpha_1=\alpha_2=\alpha_3\), and the obtained robust reliability index is used as the anchoring index. Then, determine the value of \(\alpha_2\) based on the degree of the uncertainty parameter data that has been mastered in the actual project, and finally solve the final robust reliability index under the condition of \(\alpha_1 = \alpha_3\).

[0034] As a preferred improvement, the specific solution process of the double-layer convex set nesting optimization method is as follows:

[0035] Inner layer optimization:

[0036] Taking \(\alpha\) as the variable, consider the optimization of the ratio \(r_0\) of the radial plastic displacement \(u\) of the surrounding rock to the excavation radius ip to make it satisfy the following conditions:

[0037]

[0038] Outer layer optimization:

[0039] On the premise of ensuring the stability of the surrounding rock, optimize \(\alpha\) to maximize the uncertainty parameters, that is:

[0040]

[0041] In the formula, \(f(\alpha)\) represents the objective function to be maximized, and the objective function \(f(\alpha)\) is a functional of \(\alpha\).

[0042] As a preferred improvement, in step S6, the verification process specifically includes:

[0043] ​The monotonicity of the relationship curve between the functional function of maintaining the stable state of the surrounding rock and the uncertainty parameter is judged. By fixing the fluctuation amplitude of an uncertainty parameter and observing the fluctuation amplitudes of other uncertainty parameters as the basis for judging whether the surrounding rock deformation maintains a stable state, the stable state design problem when the support resistance changes dynamically is discussed. On this basis, when the support resistance is fixed, the fluctuation amplitude of an uncertainty parameter is changed, and the calculation results of the non-probabilistic robust reliability are obtained. The rationality of the method is verified by comparing the calculation results with the actual engineering situation.

[0044] The beneficial effects of the present invention are:

[0045] (1) In order to consider the dynamic changes of uncertainty parameters in the surrounding rock of deep-buried tunnels, the present invention quantifies the specific representation methods of each uncertainty parameter in the convex set nesting model to characterize the different degrees of change that each uncertainty parameter should present in actual engineering, thereby providing a more reasonable quantitative basis for judging the stability and reliability of the surrounding rock of deep-buried tunnels, and further expanding the engineering application scope of the non-probabilistic robust design method;

[0046] (2) The present invention constructs a robustness function to define the different maximum fluctuation amplitudes of the dynamic changes of each uncertainty parameter that can be allowed before the surrounding rock of the deep tunnel deforms and becomes unstable as the corresponding robust reliability index. This index can quantitatively describe the degree to which the reliability is affected by the different changes of each uncertainty parameter, and the sensitivity of the surrounding rock to the different changes of the uncertainty parameter in maintaining a stable state;

[0047] (3) In the non-probabilistic robust design, the present invention can transform passive coping into active handling by quantitatively controlling the design variables of deep-buried tunnel support, thereby minimizing the potential instability risk caused by different fluctuation amplitudes caused by one or more uncertain parameters, so that the deep-buried tunnel engineering structure has the ability to actively resist the changes of uncertain factors when facing the influence of uncertain factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0049] Figure 1 The cohesion fluctuation amplitude α2 provided by the present invention is different support resistance p when 0.05 s Robust reliability calculation result diagram;

[0050] Figure 2Robust reliability calculation result diagram of different support resistances p when the cohesion fluctuation amplitude α2 = 0.1 provided by the present invention s ;

[0051] Figure 3 Robust reliability calculation result diagram of different support resistances p when the cohesion fluctuation amplitude α2 = 0.15 provided by the present invention s ;

[0052] Figure 4 Robust reliability calculation result diagram of different support resistances p when the cohesion fluctuation amplitude α2 = 0.2 provided by the present invention s ;

[0053] Figure 5 Robust reliability calculation result diagram of different support resistances p when the cohesion fluctuation amplitude α2 = 0.25 provided by the present invention s ;

[0054] Figure 6 Robust reliability calculation result diagram of different support resistances p when the cohesion fluctuation amplitude α2 = 0.3 provided by the present invention s ;

[0055] Figure 7 Monotonicity discrimination diagram of the relationship curve between the function of the surrounding rock maintaining a stable state and the uncertainty parameters provided by the present invention

[0056] Figure 8 Robust reliability calculation result diagram of different cohesion fluctuation amplitudes when the support resistance p s = 0.1 provided by the present invention;

[0057] Figure 9 Robust reliability calculation result diagram of different cohesion fluctuation amplitudes when the support resistance p s = 0.2 provided by the present invention;

[0058] Figure 10 Robust reliability calculation result diagram of different cohesion fluctuation amplitudes when the support resistance p s = 0.3 provided by the present invention;

[0059] Figure 11 Robust reliability calculation result diagram of different cohesion fluctuation amplitudes when the support resistance p s = 0.4 provided by the present invention;

[0060] Figure 12 Robust reliability calculation result diagram of different cohesion fluctuation amplitudes when the support resistance p s = 0.5 provided by the present invention;

[0061] Figure 13The support resistance p provided by the present invention s is the calculation result diagram of the robust reliability with different fluctuation amplitudes of cohesion when p = 0.6. Specific implementation manner

[0062] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0063] This embodiment provides a non - probabilistic robustness design method for surrounding rock of deep - buried roadway considering parameter dynamic changes, including the following steps:

[0064] Step S1, based on the existing non - probabilistic robustness design method, quantify the representation method of uncertain parameters by improving the convex - set nesting model to adapt to the fluctuation amplitude of uncertain parameters.

[0065] The uncertain parameters include the internal friction angle cohesion K and deformation modulus E of the surrounding rock of the deep - buried roadway.

[0066] Based on the existing non - probabilistic robustness design method, by improving the convex - set nesting model, taking the average value of the uncertain parameters as the nominal value under non - probabilistic conditions, the fluctuation amplitude of the uncertain parameters is expressed as:

[0067]

[0068] In the formula, u represents the vector set of uncertain parameters; α represents the vector representation of a single uncertain parameter, used to characterize the fluctuation amplitude of the uncertain parameter; c and respectively represent the unknown true value and the known nominal value of a single uncertain parameter; among them, α=(α1, α2, α3), α1 represents the vector representation of the internal friction angle , α2 represents the vector representation of the cohesion K, α3 represents the vector representation of the deformation modulus E; c=(c1, c2, c3), represents the unknown true value of the internal friction angle, c2 = K, represents the unknown true value of the cohesion K, c3 = E, represents the unknown true value of the deformation modulus; represents the known nominal value of the internal friction angle, represents the known nominal value of the cohesion, represents the known nominal value of the deformation modulus.

[0069] Step S2, through the deformation analysis control equation of the surrounding rock of the deep - buried roadway, obtain the functional function describing its stable state.

[0070] The deformation analysis control equation of the surrounding rock in deep-buried roadways, through the radial plastic displacement u of the surrounding rock ip Expressed by the ratio to the excavation radius r0, as shown in the following formula:

[0071]

[0072] In the formula, p0 represents the in-situ stress; p s Represents the support resistance; v represents the Poisson's ratio of the surrounding rock; p cr Represents the critical stress; r p Represents the radius of the plastic zone of the surrounding rock; where:

[0073]

[0074] p cr =(2p0 - σ cm );

[0075]

[0076]

[0077] In the formula, k represents a dimensionless parameter related to the internal friction angle of the surrounding rock ; σ cm Represents the uniaxial compressive strength of the surrounding rock;

[0078] Substitute the vector set u of uncertain parameters into the deformation analysis control equation to obtain the performance function R(q, u) describing the stable state of the surrounding rock, expressed as:

[0079]

[0080] In the formula, q represents the design variable, corresponding to the support resistance p s ; U c Represents the threshold value of the surrounding rock deformation control, characterizing the maximum acceptable value corresponding to the performance function R(q, u) when the surrounding rock deformation in the deep-buried roadway is stable.

[0081] Step S3, establish a robustness function based on the comparison relationship between the output response value of the performance function and its threshold value.

[0082] When the internal friction angle The cohesion K and the deformation modulus E reach their respective maximum offsets from their nominal values, and still ensure that the maximum acceptable value of the ratio of the radial plastic displacement u of the surrounding rock ip To the excavation radius r0 satisfies the performance function R(q, u), then the robustness function can be obtained, expressed as:

[0083]

[0084] In the formula, is the robust reliability index, which represents a function of the vector α and indicates the different maximum fluctuation amplitudes that the various uncertainty parameters can dynamically change before the surrounding rock deformation becomes unstable.

[0085] Step S4: Based on the established robustness function, define the maximum fluctuation amplitude that the deterministic parameters can dynamically change before the surrounding rock deformation of the deep-buried roadway becomes unstable as the robust reliability index.

[0086] Step S5: Around the reasonable selection of the support design variables, use the double-layer convex set nesting optimization method to explore the variation law of non-probabilistic robustness, providing a quantitative basis for evaluating the stability and reliability degree of the surrounding rock of the deep-buried roadway.

[0087] Around the reasonable selection of the support design variables, analyze the variation law of the non-probabilistic robustness of the surrounding rock of the deep-buried roadway, providing a quantitative basis for evaluating its stability and reliability degree. For this purpose, for the solution of in the robustness function, when calculating, first assume that α1 = α2 = α3, and use the obtained robust reliability index as the anchoring index. Determine the value of α2 in combination with the degree of the uncertainty parameter data already mastered in the engineering practice, and then solve the final robust reliability index under the condition of α1 = α3. By using the double-layer convex set nesting optimization method, its specific solution process is as follows:

[0088] (1) Inner layer optimization:

[0089] Taking α as the variable, consider the optimization of the ratio r0 of the radial plastic displacement u of the surrounding rock to the excavation radius ip by each uncertainty parameter to make it satisfy the following conditions:

[0090]

[0091] (2) Outer layer optimization:

[0092] On the premise of ensuring the stability of the surrounding rock, optimize α to maximize the uncertainty parameter, that is, there is

[0093]

[0094] In the formula, f(α) represents the objective function to be maximized, and the objective function f(α) is a functional of α;

[0095] Note that the acceptable value of the ratio of the radial plastic displacement of the surrounding rock to the excavation radius usually takes different values with the change of the support design requirements in the actual engineering. At the same time, the internal friction angle of the uncertainty parameter The cohesion K and the deformation modulus E also change dynamically. To ensure the stability of the surrounding rock deformation in deep-buried roadways, according to the actual engineering requirements, the fluctuation range of the cohesion K is first determined, and then reasonable support design variables, namely the support resistance p, are selected. s to analyze the variation law of the non-probabilistic robustness of the surrounding rock in deep-buried roadways and provide a quantitative basis for evaluating its stability and reliability.

[0096] Step S6: Use the calculation model of the surrounding rock deformation in deep-buried roadways to verify the non-probabilistic robustness design method of the surrounding rock in deep-buried roadways considering the dynamic change of parameters.

[0097] The specific verification process includes:

[0098] Perform a monotonicity discrimination on the relationship curve between the performance function for the surrounding rock to maintain a stable state and the uncertain parameters. By fixing the fluctuation range of one uncertain parameter and observing the fluctuation range of other uncertain parameters as the discrimination basis for the surrounding rock deformation to maintain a stable state, explore the stable state design problem when the support resistance changes dynamically; on this basis, when the support resistance remains unchanged, change the fluctuation range of one uncertain parameter, and then obtain the calculation results of non-probabilistic robust reliability. By comparing the calculation results with the actual engineering situation, verify the rationality of this method.

[0099] Example 1

[0100] Using the non-probabilistic robustness design method of the surrounding rock in deep-buried roadways considering the dynamic change of parameters provided by the present invention, analyze the robust reliability of different support resistances p when the fluctuation range of the cohesion α2 = 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3. s The obtained results are as Figures 1 - 6 shown. Combining Figures 1 - 6 it can be seen that when α1 = α3 and the fluctuation range α2 of the cohesion K continuously increases, it indicates that when the internal friction angle and the deformation modulus E of the allowable uncertain parameters fluctuate within the same range, to maintain the stability of the surrounding rock deformation, the maximum acceptable value U c must increase to a certain range; on the other hand, if the requirement for maintaining the stability of the surrounding rock deformation is considered to be improved during the design process, that is, when U c decreases to a certain value, since the fluctuation range α2 of the cohesion K is determined by the actual engineering situation, the support resistance p s can be adjusted. Here, according to the change ranges of the internal friction angle and the deformation modulus E of the uncertain parameters, actively control the support design variables according to the stable state requirements that the surrounding rock deformation must reach.

[0101] Figure 7The relationship between the performance function indicating the stable state of the surrounding rock and the uncertain parameters. It can be seen from each curve that as the maximum acceptable value U of the ratio of the radial plastic displacement of the surrounding rock to the excavation radius c gradually increases, the robust reliability index becomes larger, indicating that the allowable internal friction angle cohesion K and deformation modulus E of the stable state that the surrounding rock deformation possesses have a larger fluctuation range, that is, they are less sensitive to the changes of the uncertain parameters. Therefore, in this stage, it can be considered that the robustness of the surrounding rock deformation is better or its reliability degree is higher.

[0102] In addition, in this example, the design problem of the surrounding rock maintaining a stable state when the support resistance p s changes is discussed. As Figures 8 - 13 shown, when the support resistances are respectively given as p s = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, the calculation results of the robustness under the cases where the fluctuation ranges α2 of the cohesion K are 0.05, 0.1, 0.15, 0.2, 0.25, 0.3. It can be clearly seen from the figure that when the support resistance p s is larger, each curve in the figure gradually shifts upward to the vertical coordinate axis as a whole, that is, it allows the internal friction angle and the deformation modulus E to fluctuate within a larger range, which indicates that the robustness of the surrounding rock deformation to maintain a stable state is better or its reliability degree is higher.

[0103] Further, by observing one by one Figures 8 - 13 it can be known that as the support resistance p s increases (such as p s changing from 0.1 to 0.6), each curve in the figure gradually shifts upward to the vertical coordinate axis as a whole, but the upward shift trend of the curve with α1 = α2 = α3 is slower than that of other curves. This indicates that if the fluctuation range of one uncertain parameter is first determined, the sensitivity of other uncertain parameters to the support resistance p s increases. For example, when p s = 0.5, compared with the curve with α1 = α2 = α3, the acceptable value U c of other curves is larger, which obviously meets the requirements of actual engineering.

[0104] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative rather than restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims, and all belong to the protection scope of the present invention.

Claims

1. A non-probabilistic robust design method for surrounding rock of deep buried tunnels considering dynamic changes of parameters, characterized in that: The steps include: Step S1, based on the existing non-probabilistic robustness design method, the representation method of the uncertainty parameter is quantified by improving the convex set nesting model to adapt to the fluctuation range of the uncertainty parameter; Step S2, obtaining a function describing the stability of the surrounding rock of the deep tunnel through a deformation analysis control equation; Step S3, establishing a robustness function according to the comparison relationship between the output response value of the functional function and its threshold value; Step S4, based on the established robustness function, the maximum fluctuation range of the dynamic change of the deterministic parameters allowed before the surrounding rock of the deep tunnel becomes deformed and unstable is defined as a robust reliability index; Step S5, focusing on the reasonable selection of support design variables, using the double-layer convex set nesting optimization method to explore the variation law of non-probabilistic robustness, and provide a quantitative basis for judging the stability and reliability of the surrounding rock of the deep buried tunnel; Step S6, using the calculation model of the deformation of the surrounding rock of the deep buried tunnel to verify the non-probabilistic robust design method of the surrounding rock of the deep buried tunnel considering the dynamic change of parameters.

2. The non-probabilistic robustness design method for surrounding rock of deep buried tunnels considering dynamic parameter changes according to claim 1 is characterized in that: Uncertain parameters include the internal friction angle of the surrounding rock of the deep tunnel Cohesion K and deformation modulus E.

3. The non-probabilistic robust design method for surrounding rock of deep buried tunnel considering dynamic parameter changes according to claim 2 is characterized in that: Step S1 specifically includes the following process: On the basis of the existing non-probabilistic robustness design method, the convex set nesting model is improved, the average value of the uncertainty parameter is used as the nominal value under non-probabilistic conditions, and the uncertainty parameter fluctuation amplitude is expressed as: In the formula, u represents the vector set of uncertainty parameters; α represents the vector representation of a single uncertainty parameter, which is used to characterize the fluctuation amplitude of the uncertainty parameter; c and Represent the unknown true value and known nominal value of a single uncertainty parameter respectively; where α=(α1,α2,α3), α1 represents the internal friction angle α2 represents the vector representation of cohesion K, α3 represents the vector representation of deformation modulus E; c = (c1, c2, c3), represents the unknown true value of the internal friction angle, c2=K, represents the unknown true value of the cohesion, c3=E, represents the unknown true value of the deformation modulus; represents the known nominal value of the internal friction angle, represents the known nominal value of cohesion, Represents a known nominal value for the modulus of deformation.

4. The non-probabilistic robust design method for surrounding rock of deep tunnels considering dynamic parameter changes according to claim 3 is characterized in that: The deformation analysis control equation of the surrounding rock of deep buried tunnel is calculated by the radial plastic displacement u of the surrounding rock. ip The ratio of the excavation radius r0 is shown as follows: Where p0 represents the ground stress; p s represents support resistance; v represents Poisson's ratio of surrounding rock; p cr represents the critical stress; r p represents the radius of the surrounding rock plastic zone; where: p cr =(2p0-σ cm ) / (k+1); Where k represents the internal friction angle with the surrounding rock. The dimensionless parameter, σ cm It represents the uniaxial compressive strength of surrounding rock; Substituting the vector set u of uncertain parameters into the deformation analysis control equation, we can obtain the functional function R(q,u) describing the stability of the surrounding rock, which is expressed as: In the formula, q represents the design variable, corresponding to the support resistance p s ; U c It represents the threshold value of surrounding rock deformation control, and represents the maximum acceptable value of the function R(q,u) when the surrounding rock of the deep buried tunnel deforms without losing stability.

5. The non-probabilistic robust design method for surrounding rock of deep tunnels considering dynamic changes of parameters according to claim 4 is characterized in that: When the internal friction angle When the cohesion K and deformation modulus E are offset from their nominal values ​​to their respective maximums, the radial plastic displacement u of the surrounding rock can still be guaranteed. ip The maximum acceptable value of the ratio to the excavation radius r0 satisfies the functional function R(q,u), and the robustness function can be obtained, which is expressed as: In the formula, It is a robust reliability index, representing a function of the vector α, indicating the maximum fluctuation amplitudes of the dynamic changes of various uncertainty parameters that can be allowed before the surrounding rock deformation becomes unstable.

6. The non-probabilistic robust design method for surrounding rock of deep tunnels considering dynamic parameter changes according to claim 5, characterized in that: Step S5 specifically includes the following process: For the robustness function In order to solve the problem, we first assume that α1=α2=α3 during calculation. The robust reliability index obtained based on this is used as the anchor index. The value of α2 is determined based on the degree of uncertainty parameter data that has been mastered in actual engineering practice. Then, the final robust reliability index is solved under the condition that α1=α3.

7. The non-probabilistic robust design method for surrounding rock of deep tunnels considering dynamic parameter changes according to claim 6, characterized in that: The specific solution process of the double-layer convex set nesting optimization method is as follows: Inner layer optimization: Taking α as the variable, considering the influence of various uncertain parameters on the radial plastic displacement u of the surrounding rock ip Optimization of the ratio r0 to the excavation radius Make it meet the following conditions: Outer layer optimization: Under the premise of keeping the surrounding rock in a stable state, α is optimized to maximize the uncertainty parameter, that is, Where f(α) represents the objective function to be maximized, and the objective function f(α) is a universal function of α.

8. The non-probabilistic robust design method for surrounding rock of deep tunnels considering dynamic parameter changes according to claim 7, characterized in that: In step S6, the verification process specifically includes: The monotonicity of the relationship curve between the functional function of maintaining the stable state of the surrounding rock and the uncertainty parameter is judged. By fixing the fluctuation amplitude of an uncertainty parameter and observing the fluctuation amplitudes of other uncertainty parameters as the basis for judging whether the surrounding rock deformation maintains a stable state, the stable state design problem when the support resistance changes dynamically is discussed. On this basis, when the support resistance is fixed, the fluctuation amplitude of an uncertainty parameter is changed, and the calculation results of the non-probabilistic robust reliability are obtained. The rationality of the method is verified by comparing the calculation results with the actual engineering situation.

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