Method and device for safety evaluation of coiled tubing crossing a strike-slip fault, storage medium

Abstract

The application discloses a kind of safety evaluation method and device of crossing oblique slip fault continuous pipeline, storage medium, comprising: according to the mechanical boundary of pipeline and soil interaction and the limit resistance difference of the soil on both sides of oblique slip fault and fault spatial characteristics, the plastic hinge characteristic length and the rotation angle increment when pipeline deformation are determined;According to the plastic hinge characteristic length and the rotation angle increment, the deformation parameter when the system reaches stable equilibrium state is analytically calculated;According to the deformation parameter, the axial strain and bending strain of the pipeline are calculated, and the maximum tensile strain and maximum compressive strain when the continuous pipeline crosses oblique slip fault are obtained by linear superposition;According to the maximum tensile strain and the maximum compressive strain, respectively compared with the preset allowable tensile strain threshold and allowable compressive strain threshold, to determine the safety state of pipeline under the action of oblique slip fault dislocation.The application can realize the evaluation of the service performance of crossing oblique slip fault continuous pipeline.

Description

Technical Field

[0001] This invention belongs to the field of pipeline engineering technology, specifically relating to a safety assessment method and device for continuous pipelines crossing inclined slip faults, and a storage medium. Background Technology

[0002] Buried pipelines, as vital lifeline engineering projects, are highly susceptible to tensile fracture or local buckling when crossing active faults. Existing technologies mostly focus on the mechanical response of single strike-slip or dip-slip faults, but in real earthquakes, the vast majority of faults are oblique-slip faults with coupled strike-slip and dip-slip faults.

[0003] Faced with complex inclined-slip fault conditions, existing analytical models suffer from two main limitations: First, traditional two-dimensional models cannot overcome dimensional constraints. Using simple linear superposition to handle composite displacements destroys the physical reality of the pipe-soil interaction, leading to severe distortion in deformation calculations. Second, they often employ fixed empirical parameters, neglecting the impact of the inclined-slip composite displacement mechanism on the true extension range of the pipeline's plastic zone, resulting in significant errors in extreme strain assessment. Therefore, a novel safety assessment method for continuous pipelines traversing inclined-slip faults is urgently needed to address the limitations of existing technologies in terms of assessment dimensions and the rigidity of empirical parameters. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a safety assessment method, apparatus, and storage medium for continuous pipelines traversing inclined slip faults, enabling the assessment of the service performance of such pipelines.

[0005] To achieve the above objectives, the present invention provides the following solution: A safety assessment method for continuous pipelines traversing an oblique-slip fault includes: S1. Obtain the pipe geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. S2. Based on the mechanical boundary of the interaction between the pipeline and the soil, the difference in ultimate resistance of the soil on both sides of the inclined slip fault, and the spatial characteristics of the fault, determine the characteristic length of the plastic hinge and the increase in the rotation angle during pipeline deformation. S3. Based on the characteristic length of the plastic hinge and the increase in the rotation angle, and based on the actual soil displacement profile, calculate the total dissipated energy caused by the multi-directional interaction between the pipe and soil space and the deformation of the pipe. By solving for the minimum value of the total dissipated energy, analyze the deformation parameters when the system reaches a stable equilibrium state. S4. Based on the deformation parameters calculated in step S3, calculate the axial strain and bending strain of the pipeline, and obtain the maximum tensile strain and maximum compressive strain when the continuous pipeline crosses the oblique slip fault by linear superposition. S5. Based on the maximum tensile strain and maximum compressive strain calculated in step S4, compare them with the preset allowable tensile strain threshold and allowable compressive strain threshold respectively to determine the safety status of the pipeline under the action of the inclined slip fault.

[0006] Preferably, the obtained pipe geometry parameters include: outer diameter D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength The obtained soil parameters include: soil weight. c , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is .

[0007] Preferably, in step S1, the specific process of establishing the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system is as follows: establishing a three-dimensional local coordinate system with the pipe axis as the reference, and based on the obtained heave angle... α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z Determine the spatial boundary conditions for the interaction between the pipe and the soil.

[0008] Preferably, in step S5, the specific determination rule for determining the safety status of the pipeline under the action of the inclined slip fault is as follows: when the maximum tensile strain is greater than the preset allowable tensile strain threshold, the current continuous pipeline is determined to have suffered tensile fracture failure; when the absolute value of the maximum compressive strain is greater than the preset allowable compressive strain threshold, the current continuous pipeline is determined to have suffered local buckling failure.

[0009] The present invention also provides a safety assessment device for continuous pipelines traversing oblique slip faults, comprising: The first processing module is used to acquire the pipe's geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and to establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. The second processing module is used to determine the characteristic length of the plastic hinge and the amount of rotation angle increase during pipeline deformation based on the mechanical boundary of the interaction between the pipeline and the soil, the difference in ultimate resistance of the soil on both sides of the inclined slip fault, and the spatial characteristics of the fault. The third processing module is used to calculate the total dissipated energy caused by the multi-directional interaction between the pipe and soil space and the deformation of the pipe based on the characteristic length of the plastic hinge and the increase of the rotation angle, and to analyze and calculate the deformation parameters when the system reaches a stable equilibrium state by solving for the minimum value of the total dissipated energy. The fourth processing module is used to calculate the axial strain and bending strain of the pipeline based on the deformation parameters, and to obtain the maximum tensile strain and maximum compressive strain of the continuous pipeline when it crosses the oblique slip fault through linear superposition. The fifth processing module is used to compare the maximum tensile strain and maximum compressive strain with preset allowable tensile strain thresholds and allowable compressive strain thresholds, respectively, to determine the safety status of the pipeline under the action of the inclined slip fault.

[0010] Preferably, the obtained pipe geometry parameters include: outer diameter D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength The obtained soil parameters include: soil weight. c , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is .

[0011] Preferably, the first processing module is used to establish a three-dimensional local coordinate system based on the pipe axis, and to process the obtained undulation angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z Determine the spatial boundary conditions for the interaction between the pipe and the soil.

[0012] Preferably, the fifth processing module is used to determine that the current continuous pipeline has experienced tensile fracture failure when the maximum tensile strain is greater than a preset allowable tensile strain threshold; and to determine that the current continuous pipeline has experienced local buckling failure when the absolute value of the maximum compressive strain is greater than a preset allowable compressive strain threshold.

[0013] The present invention also provides a safety assessment system for continuous pipelines crossing oblique-slip faults, comprising: a memory and a processor, wherein the memory stores a computer program executed by the processor, and the computer program, when executed by the processor, performs a safety assessment method for continuous pipelines crossing oblique-slip faults.

[0014] The present invention also provides a storage medium storing a computer program that, when running, executes a safety assessment method for continuous pipelines traversing a slip-fault.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention fully considers the spatial bending ratio of continuous pipelines under the fault action of inclined slip faults, introduces the spatial equivalent angle, breaks through the dimensional limitations of traditional mechanical models, and can truly and completely reflect the three-dimensional spatial motion mechanism under the "strike-slip-dip-slip" coupling effect in inclined slip faults, thereby accurately predicting the spatial deformation trend of continuous pipelines when crossing inclined slip faults, and providing a scientific basis for subsequent pipeline safety status assessment.

[0016] 2. To address the fault characteristics under different geological environments, this invention refines the characterization of the dip angle. α Fault dip angle β The angle between the pipeline axis and the fault direction ψ This allows the assessment model to move beyond a single, specific fault movement pattern, enabling it to flexibly adapt to and cover various spatial characteristics of oblique-slip faults. It possesses strong versatility and engineering applicability, effectively meeting the actual assessment needs under different geological conditions and engineering environments.

[0017] 3. This invention, through precise strain calculation and threshold comparison mechanism, can achieve early warning of potential failure risks in continuous pipelines, providing a scientific basis for seismic safety performance assessment and disaster prevention design of pipelines crossing active faults; at the same time, it provides clear quantitative indicators for engineering operation and maintenance personnel, helping them to formulate targeted maintenance strategies and take proactive reinforcement measures, effectively reducing the probability of pipeline damage accidents; in addition, the assessment results can further assist engineering managers in optimizing pipeline route selection and layout strategies, and improving the overall level of project risk management. Attached Figure Description

[0018] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments are briefly introduced below. 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 effort.

[0019] Figure 1 This is a flowchart of the safety assessment method for continuous pipelines traversing a slip fault according to an embodiment of the present invention; Figure 2 A schematic diagram of a buried pipeline affected by a slip fault; Figure 3 (a) is a schematic diagram of the deformation mode of the curved pipe length; (b) is a schematic diagram of the pipe deformation and (c) is a schematic diagram of the spatial bending ratio under the action of the oblique slip fault. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1 like Figure 1 As shown, the present invention provides a safety assessment method for continuous pipelines traversing oblique slip faults, comprising: S1. Obtain the pipe geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. S2. Determine the characteristic length of the plastic hinge during pipeline deformation based on the difference in soil resistance on both sides of the inclined slip fault and the spatial characteristics of the fault. and the increase in rotation angle ; S3. Based on the actual soil displacement profile, calculate the total energy dissipation caused by the multi-directional interaction between the pipe and the soil space and the pipe deformation. By solving for the minimum total dissipated energy, the deformation parameters of the system when it reaches a stable equilibrium state are analytically calculated. S4. Based on the deformation parameters calculated in step S3, calculate the axial strain and bending strain of the pipeline, and obtain the maximum tensile strain and maximum compressive strain when the continuous pipeline crosses the oblique slip fault by linear superposition. S5. Based on the maximum tensile strain and maximum compressive strain calculated in step S4, compare them with the preset allowable tensile strain threshold and allowable compressive strain threshold respectively to determine the safety status of the pipeline under the action of the inclined slip fault.

[0023] In step S1, the obtained pipe geometry parameters include: outer diameter D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength s y The obtained soil parameters include: soil weight. c , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is f .

[0024] Specifically, in step S1, the process of establishing the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system is as follows: Figure 2 As shown, a three-dimensional local coordinate system is established with the pipeline axis as the reference, and the obtained undulation angle is used as the reference. α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z The calculation formula is as follows: ; Based on the direction vector in the three-dimensional local coordinate system, the spatial boundary conditions for the interaction between the pipe and the soil are determined.

[0025] This invention refines the characterization of the tilt angle. α Fault dip angle β The angle between the pipeline axis and the fault direction ψ This allows the assessment model to move beyond a single, specific fault movement pattern, enabling it to flexibly adapt to and cover various spatial characteristics of oblique-slip faults. It possesses strong versatility and engineering applicability, effectively meeting the actual assessment needs under different geological conditions and engineering environments.

[0026] Based on the obtained pipeline geometric parameters, pipe material mechanical parameters, and soil parameters, calculate the ultimate resistance of the soil surrounding the pipeline.

[0027] ; ; ; ; In the formula, t u This is the ultimate resistance of the axial soil spring, in N / m. p u It is the ultimate resistance of the lateral soil spring, in N / m. q uu It is the ultimate resistance of the vertical uplift spring, in N / m. q ud It is the ultimate resistance of the vertically bearing soil spring, in N / m; 'a' is the cohesion coefficient. K 0 is the coefficient of earth pressure at rest. f It is a coefficient related to the pipe coating. N ch and N qh It is the lateral bearing capacity factor. N cv and N qv It is the vertical pull-out coefficient. N c , N q and N γ It is the vertical bearing capacity coefficient.

[0028] like Figure 3 As shown, due to the difference in soil resistance on both sides of the fault, the bending length of the pipeline differs on both sides of the inclined slip fault. Based on the difference in the coupling of the transverse and vertical soil springs on both sides of the fault, the bending ratio of the continuous pipeline under the action of the inclined slip fault is calculated. l ratio The calculation formula is as follows: ; In the formula, K eff Equivalent spring stiffness, unit N / m 2 It can be calculated using the following formula: ; In the formula, k u Lateral soil spring stiffness, unit N / m 2 , k vdVertical uplift spring stiffness, unit N / m 2 .

[0029] Specifically, under the spatial boundary conditions of the three-dimensional local coordinate system and the interaction between the soil and the pipe, the spatial equivalent angle is calculated. β eq The calculation formula is as follows: .

[0030] This invention, by introducing a spatial equivalent angle, breaks through the dimensional limitations of traditional mechanical models and can realistically and completely reflect the three-dimensional spatial motion mechanism under the coupling effect of "strike-slip" and "dip-slip" in oblique-slip faults. This allows for accurate prediction of the spatial deformation trend of continuous pipelines crossing oblique-slip faults, providing a scientific basis for subsequent pipeline safety status assessment.

[0031] The length of the plastic hinge when the pipeline deforms under fault conditions is calculated based on the spatial equivalent angle. L p and rotation angle increment ; Characteristic length of plastic hinge during pipe deformation L p It can be calculated using the following formula: ; in, i 0 represents the pipe rotation angle; Increase in rotation angle during pipe deformation It can be calculated using the following formula: ; In the formula, This represents the minimum displacement increment of the oblique slip fault.

[0032] Specifically, in step S3, the total dissipated energy Calculated by the following formula: ; In the formula, the P rr The energy term caused by the rotation of the pipe at the plastic hinge can be calculated by the following formula: ; The P re The energy term caused by the plastic elongation of the pipe can be calculated using the following formula: ; The P rt The energy term caused by the axial displacement of the soil spring can be calculated by the following formula: ; The P rp The energy term caused by the lateral displacement of the soil spring can be calculated by the following formula: ; In the formula, y u This represents the lateral soil spring yield displacement. The P rq The energy term caused by the vertical displacement of the soil spring can be calculated by the following formula: ; In the formula, z uu This represents the yield displacement of the vertical pull-out spring. z ud This represents the yield displacement of the vertically bearing soil spring.

[0033] Specifically, in step S4, the axial strain of the pipe and bending strain It can be calculated using the following formula: ; ; In the formula, L ph This is the equivalent plastic hinge length. i The pipe rotation angle is the angle at which the total energy dissipation of the system is minimized.

[0034] Specifically, the maximum tensile strain and the maximum compressive strain can be calculated by the following formula: ; .

[0035] Specifically, the equivalent plastic hinge length L ph The calculation formula is: in, N These are empirical coefficients determined based on the characteristics of oblique-slip faults, and N The value range is 3 to 5.

[0036] It should be noted that the deformable plastic hinge feature length used in this invention... L p The extent of the overall macroscopic deformation zone of the pipeline is used to characterize the local curvature feature length used in strain assessment; L phBoth are used to capture abrupt changes in curvature of local cross sections, and together they ensure the accuracy of multi-scale mechanical response calculations.

[0037] Specifically, in step S5, the determination of the safety status of the pipeline under the action of the inclined slip fault is based on the following rule: when the maximum tensile strain... e tensile If the tensile strain exceeds the preset allowable threshold, the current continuous pipeline is determined to have experienced tensile fracture failure; when the maximum compressive strain... e buckling When the absolute value of the strain exceeds the preset allowable compressive strain threshold, the current continuous pipeline is determined to have experienced local buckling failure.

[0038] Table 1

[0039] As can be seen from the data in Table 1, the trend of the maximum tensile strain of the pipeline calculated by the method of this invention is in high agreement with the test results of the physical model as the displacement of the inclined slip fault continues to increase. Under various displacement conditions, the relative error is strictly controlled within 5%, verifying the practicality and superiority of the method.

[0040] Example 2 The present invention also provides a safety assessment device for continuous pipelines traversing oblique slip faults, comprising: The first processing module is used to acquire the pipe's geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and to establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. The second processing module is used to determine the characteristic length of the plastic hinge and the amount of rotation angle increase during pipeline deformation based on the mechanical boundary of the interaction between the pipeline and the soil, the difference in ultimate resistance of the soil on both sides of the inclined slip fault, and the spatial characteristics of the fault. The third processing module is used to calculate the total dissipated energy caused by the multi-directional interaction between the pipe and soil space and the deformation of the pipe based on the characteristic length of the plastic hinge and the increase of the rotation angle, and to analyze and calculate the deformation parameters when the system reaches a stable equilibrium state by solving for the minimum value of the total dissipated energy. The fourth processing module is used to calculate the axial strain and bending strain of the pipeline based on the deformation parameters, and to obtain the maximum tensile strain and maximum compressive strain of the continuous pipeline when it crosses the oblique slip fault through linear superposition. The fifth processing module is used to compare the maximum tensile strain and maximum compressive strain with preset allowable tensile strain thresholds and allowable compressive strain thresholds, respectively, to determine the safety status of the pipeline under the action of the inclined slip fault.

[0041] As one embodiment of the present invention, the obtained pipe geometric parameters include: outer diameter.D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength The obtained soil parameters include: soil weight. c , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is .

[0042] In one embodiment of the present invention, the first processing module is used to establish a three-dimensional local coordinate system based on the pipeline axis, and to process the obtained undulation angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z Determine the spatial boundary conditions for the interaction between the pipe and the soil.

[0043] As one embodiment of the present invention, the fifth processing module is used to determine that the current continuous pipeline has experienced tensile fracture failure when the maximum tensile strain is greater than a preset allowable tensile strain threshold; and to determine that the current continuous pipeline has experienced local buckling failure when the absolute value of the maximum compressive strain is greater than the preset allowable compressive strain threshold.

[0044] Example 3 The present invention also provides a storage medium storing a computer program that, when running, executes a safety assessment method for continuous pipelines traversing a slip-fault.

[0045] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for safety assessment of a coiled tubing crossing a listric fault, characterized in that, include: S1. Obtain the pipe geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. S2. Based on the mechanical boundary of the interaction between the pipeline and the soil, the difference in ultimate resistance of the soil on both sides of the inclined slip fault, and the spatial characteristics of the fault, determine the characteristic length of the plastic hinge and the increase in the rotation angle during pipeline deformation. S3. Based on the characteristic length of the plastic hinge and the increase in the rotation angle, and based on the actual soil displacement profile, calculate the total dissipated energy caused by the multi-directional interaction between the pipe and soil space and the deformation of the pipe. By solving for the minimum value of the total dissipated energy, analyze the deformation parameters when the system reaches a stable equilibrium state. S4. Based on the deformation parameters calculated in step S3, calculate the axial strain and bending strain of the pipeline, and obtain the maximum tensile strain and maximum compressive strain when the continuous pipeline crosses the oblique slip fault by linear superposition. S5. Based on the maximum tensile strain and maximum compressive strain calculated in step S4, compare them with the preset allowable tensile strain threshold and allowable compressive strain threshold respectively to determine the safety status of the pipeline under the action of the inclined slip fault.

2. The safety assessment method for continuous pipelines crossing oblique-slip faults as described in claim 1, characterized in that, The obtained pipe geometry parameters include: outer diameter D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength The obtained soil parameters include: soil weight. γ , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is .

3. The safety assessment method for continuous pipelines traversing oblique-slip faults as described in claim 2, characterized in that, In step S1, the specific process of establishing the mechanical boundary of the interaction between the pipeline and the soil in a three-dimensional spatial coordinate system is as follows: establishing a three-dimensional local coordinate system with the pipeline axis as the reference, and based on the obtained heave angle... α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z Determine the spatial boundary conditions for the interaction between the pipe and the soil.

4. The safety assessment method for continuous pipelines crossing oblique-slip faults as described in claim 3, characterized in that, In step S5, the specific determination rule for determining the safety status of the pipeline under the action of the inclined slip fault is as follows: when the maximum tensile strain is greater than the preset allowable tensile strain threshold, the current continuous pipeline is determined to have experienced tensile fracture failure; when the absolute value of the maximum compressive strain is greater than the preset allowable compressive strain threshold, the current continuous pipeline is determined to have experienced local buckling failure.

5. A safety assessment device for a continuous pipeline traversing an oblique slip fault, characterized in that, include: The first processing module is used to acquire the pipe's geometric parameters, pipe material mechanical parameters, soil parameters, inclined slip fault spatial geometric parameters and displacement, and to establish the mechanical boundary of the interaction between the pipe and the soil in a three-dimensional spatial coordinate system. The second processing module is used to determine the characteristic length of the plastic hinge and the amount of rotation angle increase during pipeline deformation based on the mechanical boundary of the interaction between the pipeline and the soil, the difference in ultimate resistance of the soil on both sides of the inclined slip fault, and the spatial characteristics of the fault. The third processing module is used to calculate the total dissipated energy caused by the multi-directional interaction between the pipe and soil space and the deformation of the pipe based on the characteristic length of the plastic hinge and the increase of the rotation angle, and to analyze and calculate the deformation parameters when the system reaches a stable equilibrium state by solving for the minimum value of the total dissipated energy. The fourth processing module is used to calculate the axial strain and bending strain of the pipeline based on the deformation parameters, and to obtain the maximum tensile strain and maximum compressive strain of the continuous pipeline when it crosses the oblique slip fault through linear superposition. The fifth processing module is used to compare the maximum tensile strain and maximum compressive strain with preset allowable tensile strain thresholds and allowable compressive strain thresholds, respectively, to determine the safety status of the pipeline under the action of the inclined slip fault.

6. The safety assessment device for continuous pipelines traversing inclined slip faults as described in claim 5, characterized in that, The obtained pipe geometry parameters include: outer diameter D Wall thickness t burial depth H The obtained mechanical parameters of the pipe include: elastic modulus. E Yield strength The obtained soil parameters include: soil weight. γ , soil internal friction angle Cohesion c The obtained spatial geometric parameters of the oblique slip fault include the dip angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ The obtained displacement of the oblique slip fault is .

7. The safety assessment device for continuous pipelines traversing inclined slip faults as described in claim 6, characterized in that, The first processing module is used to establish a three-dimensional local coordinate system based on the pipe axis, and to process the obtained undulation angle. α ,inclination β and the angle between the pipeline axis and the fault direction ψ Calculate the direction vector of the slip displacement of the oblique slip fault in the three-dimensional local coordinate system. n x , n y and n z Determine the spatial boundary conditions for the interaction between the pipe and the soil.

8. The safety assessment device for continuous pipelines traversing inclined slip faults as described in claim 7, characterized in that, The fifth processing module is used to determine that the current continuous pipeline has experienced tensile fracture failure when the maximum tensile strain is greater than a preset allowable tensile strain threshold; and to determine that the current continuous pipeline has experienced local buckling failure when the absolute value of the maximum compressive strain is greater than a preset allowable compressive strain threshold.

9. A storage medium, characterized in that, The storage medium stores a computer program that, when executed, performs the safety assessment method for continuous pipelines traversing an oblique slip fault as described in any one of claims 1-4.

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