Construction method and device of interface mechanical model, medium and equipment

Abstract

The invention relates to a construction method and device of an interface mechanical model, a medium and equipment, and belongs to the technical field of ocean engineering.The method comprises the following steps that A, a viscoelastic constitutive model of a steel and high polymer material interface is established, comprising an expression of stress and displacement when the interface of the steel and the high polymer material is subjected to normal and tangential loads; b, based on a calculation formula of a cohesion model damage value, establishing a tangential and normal mixed damage model of the steel and high polymer material interface through rigidity, fracture toughness and critical damage initial stress of a spring of the steel and high polymer material interface; c, according to the viscoelastic constitutive model of the interface of the steel and the high polymer material and the tangential and normal mixed damage model of the interface of the steel and the high polymer material, the ultimate bearing characteristics of the marine composite hose at different load loading rates are analyzed.

Description

Technical Field

[0001] The present invention belongs to the field of marine engineering technology, and in particular relates to a method, device, medium and equipment for constructing an interface mechanics model. Background Art

[0002] Composite structures are widely used in aerospace, marine, automotive, construction, and infrastructure due to their high specific strength and stiffness, excellent corrosion resistance and durability, and good design flexibility. In composite structures, the contact area between the different component materials is called the interface. The interface is often the weakest link in a composite structure. This is due to its low interfacial strength. Interfacial bonding typically relies on physical adsorption or chemical bonding. Compared to the strength of the material itself (such as the fiber or matrix), these bonds are generally weak and prone to failure under load or environmental conditions. Furthermore, differences in the properties of the component materials can easily cause the interface to become a starting point for crack initiation. For example, differences in the thermal expansion coefficients of the different component materials can lead to residual stresses at the interface when the temperature changes. When the elastic modulus of the matrix and reinforcement differ significantly, the interface may be subject to higher shear stresses during deformation. The performance of composite materials depends on the interface transferring external loads from the matrix to the reinforcement. Insufficient interfacial bonding can reduce stress transfer efficiency and even cause local debonding, leading to failure of the composite structure.

[0003] Marine composite hoses are typical composite structures in the field of marine engineering and play a vital role in the development of offshore resources. Marine composite hoses can be divided into two types: bonded and non-bonded. Bonded hoses have an interface between steel and rubber, while non-bonded hoses have an interface between steel and epoxy resin adhesive. Existing research shows that many interfaces, such as the interface between steel and rubber and the interface between steel and epoxy adhesive, exhibit viscoelastic mechanical behavior. These interfaces are prone to creep and stress relaxation, and their mechanical response is related to the load loading rate. In harsh marine environments, the failure of marine composite flexible hoses is usually caused by loads with large amplitudes and fast loading rates.

[0004] However, in the study of the ultimate load-bearing capacity of composite flexible hoses, the mechanical behavior of the interface between steel and rubber or steel and epoxy resin adhesive in the hose is mostly simulated using the cohesive force model. The cohesive force model does not consider the influence of the load loading rate on the mechanical behavior of the interface, resulting in the inability to accurately analyze the ultimate load-bearing characteristics of marine composite hoses under different load loading rates. Summary of the Invention

[0005] In view of the above problems, the purpose of the present invention is to provide a method for constructing an interface mechanics model to solve the current problem that the ultimate load-bearing characteristics of marine composite hoses under different load loading rates cannot be accurately analyzed.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention discloses a method for constructing an interface mechanics model, comprising:

[0008] Step A: Establish a viscoelastic constitutive model for the interface between steel and polymer, including the relationship between stress and displacement at a point on the interface between steel and polymer when subjected to normal and tangential loads;

[0009] Step B: Based on the calculation formula of the cohesive force model damage value, the stiffness, fracture toughness and critical damage initiation stress of the interface spring between steel and polymer are used to establish a mixed tangential and normal damage model of the interface between steel and polymer;

[0010] Step C: Analyze the ultimate load-bearing characteristics of the marine composite hose at different loading rates based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material.

[0011] In step A, the relationship between the normal stress and displacement at a certain point on the interface between the steel and the polymer material is:

[0012]

[0013] Where, σ n is the stress in the normal direction at a certain point on the interface between steel and polymer material, where n represents the normal direction;

[0014] δ n is the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0015] is the 0th spring stiffness in the normal direction;

[0016] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0017] t is the time variable;

[0018] P1 is the number of Maxwell elements in the normal direction;

[0019] i is the Maxwell unit in one of the normal directions;

[0020] E i nis the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0021] is the relaxation time of the i-th Maxwell element in the normal direction;

[0022] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t;

[0023] e is a natural constant;

[0024] It represents the stress of all Maxwell elements in the normal direction when they are under load for the total time T and are in tension, or 0 when they are in compression;

[0025] K c is the compression factor.

[0026] In step A, the relationship between the tangential stress and displacement at a certain point on the interface between the steel and the polymer material is:

[0027]

[0028] Where, σ s is the tangential stress at a certain point on the interface between steel and polymer material, where s represents the tangential direction;

[0029] δ s is the tangential displacement of a point on the interface between steel and polymer material;

[0030] is the 0th spring stiffness in the tangential direction;

[0031] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0032] t is the time variable;

[0033] P2 is the number of Maxwell elements in the tangential direction;

[0034] j is the Maxwell unit in one of the tangential directions;

[0035] is the stiffness of the spring of the j-th Maxwell element in the tangential direction;

[0036] is the relaxation time of the i-th Maxwell unit in the tangential direction;

[0037] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t;

[0038] e is a natural constant.

[0039] Preferably, the step B includes the following specific steps:

[0040] Step B1: Determine the calculation formula for the damage value of the cohesive force model, which is expressed as follows:

[0041]

[0042] Where t is the time variable; δ m is the equivalent separation displacement at a certain point on the interface between steel and polymer material;

[0043] D(δ m (t)) is the equivalent interface separation displacement δ at a certain point on the interface between steel and polymer material at time t m The interface damage value caused by

[0044] δ m (t) is the equivalent displacement of a point on the interface between steel and polymer material at time t;

[0045] is the equivalent damage initiation separation displacement of the interface between steel and polymer material;

[0046] is the equivalent failure separation displacement of the interface between steel and polymer material;

[0047] Step B2: Equivalent damage initial separation displacement of the interface between the steel and the polymer material Calculation of

[0048] Step B3: Equivalent failure separation displacement of the interface between the steel and the polymer material Calculation.

[0049] Furthermore, the step B2 includes the following specific steps:

[0050] Step B21: Determine the equivalent damage initial separation displacement of the interface between the steel and the polymer material The expression of the equivalent damage initiation separation displacement of the interface between the steel and the polymer material is established by this expression and the 0th spring stiffness in the normal direction The 0th spring stiffness in the tangential direction and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of

[0051] Among them, the equivalent damage starting separation displacement of the interface between the steel and the polymer material is The expression is:

[0052]

[0053] Where, is the equivalent damage initiation separation displacement of the interface between steel and polymer material;

[0054] β is the displacement composite ratio;

[0055] It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only;

[0056] It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load;

[0057] is the 0th spring stiffness in the tangential direction of the interface between steel and polymer material;

[0058] is the 0th spring stiffness in the normal direction of the interface between steel and polymer material;

[0059] Step B22: Determine the zeroth spring stiffness in the normal direction of the interface between the steel and polymer materials The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression of

[0060] Among them, the zeroth spring stiffness in the normal direction of the interface between the steel and the polymer material is The expression:

[0061]

[0062] Where, is the first fitting parameter of the normal spring stiffness of the interface between steel and polymer material;

[0063] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0064] is the second fitting parameter of the normal spring stiffness of the interface between steel and polymer material.

[0065] The 0th spring stiffness in the tangential direction of the interface between the steel and the polymer material The expression is:

[0066]

[0067] Where, is the first fitting parameter of the tangential spring stiffness of the interface between steel and polymer material;

[0068] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0069] is the second fitting parameter of the tangential spring stiffness at the interface between steel and polymer material.

[0070] The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is:

[0071]

[0072] Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material;

[0073] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0074] It is the second fitting parameter of the normal critical damage initiation stress of the interface between steel and polymer materials.

[0075] The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression:

[0076]

[0077] Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material;

[0078] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0079] It is the first fitting parameter of the critical tangential damage initiation stress at the interface between steel and polymer materials.

[0080] Step B23: Calculate the zeroth spring stiffness in the normal direction of the interface between steel and polymer material. The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent damage initial separation displacement of the interface between the steel and the polymer material

[0081] Preferably, step B3 includes the following specific steps:

[0082] Step B31: Determine the equivalent failure separation displacement of the interface between the steel and the polymer material The equivalent failure separation displacement of the interface between the steel and the polymer material is established by this expression Normal fracture toughness at the interface between steel and polymer materials Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of

[0083] The equivalent failure separation displacement of the interface between the steel and the polymer material The expression is:

[0084]

[0085] Where, is the equivalent failure separation displacement of the interface between steel and polymer material;

[0086] β is the displacement composite ratio;

[0087] λ is the energy recombination ratio;

[0088] κ is the stress composite ratio;

[0089] η is the BK criterion coefficient;

[0090] is the normal fracture toughness of the interface between steel and polymer material;

[0091] is the tangential fracture toughness of the interface between steel and polymer material;

[0092] It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only;

[0093] It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load;

[0094] Step B32: Determine the normal fracture toughness of the steel and polymer interfaces Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression of

[0095] Among them, the normal fracture toughness of the interface between the steel and the polymer material is The expression is:

[0096]

[0097] Where, The first fitting parameter of the normal fracture toughness of the interface between steel and polymer material;

[0098] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0099] It is the second fitting parameter of the normal fracture toughness of the interface between steel and polymer materials.

[0100] The tangential fracture toughness of the interface between the steel and the polymer material The expression is:

[0101]

[0102] Where, It is the first fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials;

[0103] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0104] It is the second fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials.

[0105] The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is:

[0106]

[0107] Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material;

[0108] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0109] It is the second fitting parameter of the normal critical damage initiation stress of the interface between steel and polymer materials.

[0110] The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression:

[0111]

[0112] Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material;

[0113] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0114] It is the first fitting parameter of the critical tangential damage initiation stress at the interface between steel and polymer materials.

[0115] Step B33: Normal fracture toughness of the interface between steel and polymer material Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent failure separation displacement of the interface between the steel and the polymer material

[0116] Preferably, the step C includes the following specific steps:

[0117] Step C1: Based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the mixed tangential and normal damage model of the interface between the steel and the polymer material, expressions for interface stress and displacement taking into account interface damage are obtained;

[0118] Step C2: Discretizing the expressions of interface stress and displacement between the steel and polymer material considering interface damage to obtain discretized expressions of normal stress and displacement and discretized expressions of tangential stress and displacement;

[0119] Step C3: Apply the discretized expressions of normal stress and displacement and the discretized expressions of tangential stress and displacement to analyze the ultimate bearing characteristics of the marine composite hose under different loading rates.

[0120] In a second aspect, the present invention also discloses a device for constructing an interface mechanics model, comprising:

[0121] The first processing unit is used to establish a viscoelastic constitutive model of the interface between steel and polymer materials, including the stress-displacement relationship of a certain point on the interface between steel and polymer materials when subjected to normal and tangential loads;

[0122] The second processing unit is used to establish a mixed tangential and normal damage model of the interface between steel and polymer material based on the calculation formula of the cohesive force model damage value and the stiffness, fracture toughness and critical damage initiation stress of the spring at the interface between steel and polymer material;

[0123] The third processing unit is used to analyze the ultimate bearing characteristics of the marine composite hose under different load loading rates based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material.

[0124] In a third aspect, the present invention further discloses a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the above method when executed by a processor.

[0125] In a fourth aspect, the present invention further discloses a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned method when executing the computer program.

[0126] Compared with the prior art, the present invention has the following beneficial effects:

[0127] The present invention discloses a method for constructing an interface mechanics model, comprising the following steps: Step A: establishing a viscoelastic constitutive model of the interface between steel and polymer materials, including expressions for stress and displacement of the interface between the steel and polymer materials when subjected to normal and tangential loads; Step B: establishing a tangential and normal mixed damage model of the interface between the steel and polymer materials based on a calculation formula for the damage value of a cohesive force model and by using the stiffness, fracture toughness, and critical damage initiation stress of the spring at the interface between the steel and polymer materials; Step C: analyzing the ultimate load-bearing characteristics of a marine composite hose under different load loading rates based on the viscoelastic constitutive model of the interface between the steel and polymer materials and the tangential and normal mixed damage model of the interface between the steel and polymer materials. The present invention discloses a method for constructing an interface mechanics model, which adopts a cohesive force model simulation and considers the influence of the load loading rate on the mechanical behavior of the interface, thereby solving the current problem of being unable to accurately analyze the ultimate load-bearing characteristics of a marine composite hose under different load loading rates. BRIEF DESCRIPTION OF THE DRAWINGS

[0128] Figure 1 It is a flow chart of the method for constructing the interface mechanics model provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0129] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0130] The interface is often the weakest link in a composite structure. Therefore, establishing a model that can accurately describe the mechanical behavior of the interface is of great significance for accurately evaluating the ultimate bearing characteristics of the composite structure. Marine flexible hoses are typical applications of composite structures in the field of marine engineering. In harsh marine environments, the failure of marine composite flexible hoses is usually caused by loads with large amplitudes and fast loading rates. However, most current interface mechanics models do not consider the influence of load loading rate on the mechanical behavior of the interface. The present invention establishes an interface viscoelastic constitutive model based on the generalized Maxwell model, and on the basis of the existing cohesive force model, modifies the interface fracture toughness, interface strength, and interface stiffness of the existing interface mechanics model, and proposes a method for constructing an interface mechanics model in which the interface fracture toughness, interface strength, and interface stiffness change with the load loading rate. The method is suitable for marine composite hoses and other composite structures, and can realize the simulation of interface mechanical behavior within a wide load loading rate range (0.01mm / min-500mm / min). The model used to describe the mechanical behavior of the interface under different load loading rates is of great significance, and can accurately analyze the ultimate bearing characteristics of marine composite hoses under different load loading rates.

[0131] Example 1: A method for constructing an interface mechanics model

[0132] Example 1 of the present invention proposes a method for constructing an interface mechanical model, wherein the interface is the interface between steel and polymer material, the polymer material is rubber or epoxy resin adhesive, and is suitable for marine composite hoses. Figure 1 , the method for constructing the interface mechanical model includes the following steps:

[0133] Step A: Establish a viscoelastic constitutive model of the interface between steel and polymer, including the stress-displacement relationship of a certain point on the interface between steel and polymer when subjected to normal and tangential loads.

[0134] Among them, the relationship between the normal stress and displacement at a certain point on the interface between steel and polymer material is:

[0135]

[0136] Where, σ n is the stress in the normal direction at a certain point on the interface between steel and polymer material, where n represents the normal direction;

[0137] δ n is the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0138] is the 0th spring stiffness in the normal direction;

[0139] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0140] t is the time variable;

[0141] P1 is the number of Maxwell elements in the normal direction;

[0142] i is the Maxwell unit in one of the normal directions;

[0143] E i n is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0144] is the relaxation time of the i-th Maxwell element in the normal direction;

[0145] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t;

[0146] e is a natural constant;

[0147] It represents the stress of all Maxwell elements in the normal direction when they are under load for the total time T and are in tension, or 0 when they are in compression;

[0148] K c is the compression factor, which is the ratio of the interface stiffness during compression to the interface stiffness during tension.

[0149] The relationship between the tangential stress and displacement at a certain point on the interface between steel and polymer material is:

[0150]

[0151] Where, σ s is the tangential stress at a certain point on the interface between steel and polymer material, where s represents the tangential direction;

[0152] δ sis the tangential displacement of a point on the interface between steel and polymer material;

[0153] is the 0th spring stiffness in the tangential direction;

[0154] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0155] t is the time variable;

[0156] P2 is the number of Maxwell elements in the tangential direction;

[0157] j is the Maxwell unit in one of the tangential directions;

[0158] is the stiffness of the spring of the j-th Maxwell element in the tangential direction;

[0159] is the relaxation time of the i-th Maxwell unit in the tangential direction;

[0160] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t;

[0161] e is a natural constant.

[0162] Since the generalized Maxwell model can capture the more complex rheological behavior of viscoelastic materials, the viscoelastic constitutive model of the interface between steel and polymer materials is based on the generalized Maxwell model and is proposed on the basis of the existing cohesion model.

[0163] Taking the case of the interface under normal load as an example, the relationship between interface stress and displacement is derived. The derivation process is as follows:

[0164] According to the generalized Maxwell model, the expression of the interface free energy potential is obtained as follows:

[0165]

[0166] Where, n is the free energy potential at the interface between steel and polymer, where n represents the normal direction;

[0167] is the 0th spring stiffness in the normal direction;

[0168] δ n is the normal displacement of a point on the interface between steel and polymer material, <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n >- Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0169] P1 is the number of Maxwell elements in the normal direction;

[0170] i is the Maxwell unit in one of the normal directions;

[0171] is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0172] is the displacement of the damper of the i-th Maxwell element in the normal direction;

[0173] It is the difference between the normal displacement of a point on the interface in the normal direction when the interface between steel and polymer material is stretched and the displacement of the damper of the i-th Maxwell unit in the normal direction, or 0 when under compression;

[0174] K c is the compression factor, which is the ratio of the interface stiffness during compression to the interface stiffness during tension.

[0175] Assuming that the system is isothermal, the expression of the interface free energy potential is fully differentiated according to the second law of thermodynamics to obtain the expression of the interface free energy potential after full differential treatment:

[0176]

[0177] Where, σ n is the stress in the normal direction at a certain point on the interface between steel and polymer material, where n represents the normal direction;

[0178] δ n is the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0179] is the 0th spring stiffness in the normal direction;

[0180] P1 is the number of Maxwell elements in the normal direction;

[0181] i is the Maxwell unit in one of the normal directions;

[0182] is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0183] is the displacement of the damper of the i-th Maxwell element in the normal direction;

[0184] It is the difference between the normal displacement of a point on the interface in the normal direction when the interface between steel and polymer material is stretched and the displacement of the damper of the i-th Maxwell unit in the normal direction, or 0 when under compression;

[0185] K c is the compression factor.

[0186] It is the first-order differential expression of the displacement of a certain point on the interface between steel and polymer material in the normal direction.

[0187] Among them, the sufficient conditions for the expression of the interface free energy potential after full differential treatment are as follows:

[0188]

[0189] Where σ n is the stress in the normal direction at a certain point on the interface between steel and polymer material, where n represents the normal direction;

[0190] δ n is the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0191] is the 0th spring stiffness in the normal direction;

[0192] P1 is the number of Maxwell elements in the normal direction;

[0193] i is the Maxwell unit in one of the normal directions;

[0194] is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0195] is the displacement of the damper of the i-th Maxwell element in the normal direction;

[0196] It is the difference between the normal displacement of a point on the interface in the normal direction when the interface between steel and polymer material is stretched and the displacement of the damper of the i-th Maxwell unit in the normal direction, or 0 when under compression;

[0197] Kc is the compression factor.

[0198] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction;

[0199] The viscoelastic dissipation of the viscoelastic part can be expressed using the Boltzmann superposition principle, which states that stress relaxation is the linear sum of various relaxation processes throughout the loading history. The stress response expression is:

[0200]

[0201] Where, is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0202] P1 is the number of Maxwell elements in the normal direction;

[0203] i is the Maxwell unit in one of the normal directions;

[0204] δ n is the normal displacement of a point on the interface between steel and polymer material

[0205] is the displacement of the damper of the i-th Maxwell element in the normal direction;

[0206] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0207] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at the time variable τ

[0208] It is the difference between the normal displacement of a point on the interface of steel and polymer material when the interface is stretched in the normal direction and the displacement of the damper of the i-th Maxwell unit in the normal direction, or 0 when under compression;

[0209] J(Tt) is the relaxation modulus of the interface between steel and polymer material at time Tt

[0210] t is the time variable;

[0211] It represents the sum of various relaxation processes in the entire load history when the interface between steel and polymer material is stretched in the normal direction, or 0 when compressed.

[0212] The generalized Maxwell model consists of multiple Maxwell units connected in parallel. The normal stress σ at a certain point on the interface between steel and polymer material is n The expression is:

[0213]

[0214] Where, and represent the stresses of the first, second, i-th and last Maxwell element in the tangential direction, respectively.

[0215] The normal stress σ at a certain point on the interface between steel and polymer material n Take the Laplace transform and simplify it, then take the inverse Laplace transform to get the expression after the inverse Laplace transform:

[0216]

[0217] Where J(t) is the relaxation modulus of the interface between steel and polymer at time τ

[0218] P1 is the number of Maxwell elements in the normal direction;

[0219] i is the Maxwell unit in one of the normal directions;

[0220] is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0221] is the relaxation time of the i-th Maxwell element in the normal direction;

[0222] t is the time variable;

[0223] e is a natural constant.

[0224] According to the stress response expression of the linear sum of various relaxation processes in the entire load history, the stress σ at a certain point on the interface between steel and polymer material in the normal direction n The expression of and the expression after Laplace inverse transformation can be used to obtain the expression of the normal stress at a certain point on the interface between the above-mentioned steel and polymer material.

[0225] Similarly, using the same method described above, the relationship between stress and displacement in the tangential direction at a point on the interface between steel and polymer can be obtained. Interfaces typically exhibit similar mechanical properties in the tangential direction, and this paper assumes that the mechanical behavior of the interface in the tangential direction is the same.

[0226] Step B: Based on the calculation formula of the cohesive force model damage value, and by taking into account the stiffness, fracture toughness, and critical damage initiation stress of the interface spring between steel and polymer, a mixed tangential and normal damage model of the interface between steel and polymer is established, which includes the following steps:

[0227] Step B1: Determine the calculation formula for the damage value of the cohesive force model, which is expressed as follows:

[0228]

[0229] Where t is the time variable; δ m is the equivalent separation displacement at a certain point on the interface between steel and polymer material;

[0230] D(δ m (t)) is the equivalent interface separation displacement δ at a certain point on the interface between steel and polymer material at time t m The interface damage value caused by

[0231] δ m (t) is the equivalent displacement of a point on the interface between steel and polymer material at time t;

[0232] is the equivalent damage initiation separation displacement of the interface between steel and polymer material;

[0233] is the equivalent failure separation displacement of the interface between steel and polymer material.

[0234] Step B2: Equivalent damage initial separation displacement of the interface between the steel and the polymer material The calculation includes the following steps:

[0235] Step B21: Determine the equivalent damage initial separation displacement of the interface between the steel and the polymer material The expression of the equivalent damage initiation separation displacement of the interface between the steel and the polymer material is established by this expression and the 0th spring stiffness in the normal direction The 0th spring stiffness in the tangential direction and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of

[0236] Among them, the equivalent damage starting separation displacement of the interface between the steel and the polymer material is The expression is:

[0237]

[0238] Where, is the equivalent damage initiation separation displacement of the interface between steel and polymer material;

[0239] β is the displacement composite ratio,

[0240] It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only;

[0241] It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load;

[0242] is the 0th spring stiffness in the tangential direction of the interface between steel and polymer material;

[0243] It is the 0th spring stiffness in the normal direction of the interface between steel and polymer material.

[0244] Specifically, the expression of displacement composite ratio β is:

[0245] β=δ s / δ n (Equation 11)

[0246] Among them, δ s is the tangential displacement of a certain point on the interface between steel and polymer material;

[0247] δ n is the normal displacement of a point on the interface between steel and polymer material.

[0248] Commonly used damage initiation criteria include the maximum nominal stress criterion, the maximum nominal strain criterion, the quadratic nominal stress criterion, and the quadratic nominal strain criterion. The maximum nominal stress criterion and the maximum nominal strain criterion do not consider the interaction between stresses or strains in different directions. In addition, the quadratic nominal stress criterion is usually more conservative than the quadratic nominal strain criterion. The present invention uses the quadratic nominal stress criterion as the damage initiation criterion of the modified cohesive force model to calculate the equivalent damage initiation separation displacement of the interface between steel and polymer materials.

[0249] Step B22: Determine the zeroth spring stiffness in the normal direction of the interface between the steel and polymer materials The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression of

[0250] Among them, the zeroth spring stiffness in the normal direction of the interface between the steel and the polymer material is The expression:

[0251]

[0252] Where, is the first fitting parameter of the normal spring stiffness of the interface between steel and polymer material;

[0253] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0254] is the second fitting parameter of the normal spring stiffness of the interface between steel and polymer material.

[0255] The 0th spring stiffness in the tangential direction of the interface between the steel and the polymer material The expression is:

[0256]

[0257] Where, The first fitting parameter of the tangential spring stiffness of the interface between steel and polymer material

[0258] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material

[0259] is the second fitting parameter of the tangential spring stiffness at the interface between steel and polymer material.

[0260] The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is:

[0261]

[0262] Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material;

[0263] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0264] It is the second fitting parameter of the normal critical damage initiation stress of the interface between steel and polymer materials.

[0265] The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression:

[0266]

[0267] Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material;

[0268] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0269] It is the first fitting parameter of the critical tangential damage initiation stress at the interface between steel and polymer materials.

[0270] Step B23: Calculate the zeroth spring stiffness in the normal direction of the interface between steel and polymer material. The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent damage initial separation displacement of the interface between the steel and the polymer material

[0271] Step B3: Equivalent failure separation displacement of the interface between the steel and the polymer material The calculation includes the following steps:

[0272] Step B31: Determine the equivalent failure separation displacement of the interface between the steel and the polymer material The equivalent failure separation displacement of the interface between the steel and the polymer material is established by this expression Normal fracture toughness at the interface between steel and polymer materials Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of

[0273] The equivalent failure separation displacement of the interface between the steel and the polymer material The expression is:

[0274]

[0275] Where, is the equivalent failure separation displacement of the interface between steel and polymer material;

[0276] β is the displacement composite ratio;

[0277] λ is the energy recombination ratio;

[0278] η is the BK criterion coefficient;

[0279] is the normal fracture toughness of the interface between steel and polymer material;

[0280] is the tangential fracture toughness of the interface between steel and polymer material;

[0281] It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only;

[0282] It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load;

[0283] κ is the stress composite ratio.

[0284] Specifically, the expression of displacement composite ratio β is:

[0285] β=δ s / δ n (Equation 17)

[0286] Where, δ s is the tangential displacement of a certain point on the interface between steel and polymer material;

[0287] δ n is the normal displacement of a point on the interface between steel and polymer material.

[0288] Specifically, the expression of the energy recombination ratio λ is:

[0289] λ=G s / G n (Equation 18)

[0290] Where G s is the energy release rate at a certain point on the interface between steel and polymer material;

[0291] G n It is the energy release rate at a certain point on the interface between steel and polymer material.

[0292] Specifically, the expression of stress composite ratio κ is:

[0293] κ=σ s / σ n (Equation 19)

[0294] Where σ s is the tangential stress at a certain point on the interface between steel and polymer material;

[0295] σ n is the normal stress at a certain point on the interface between steel and polymer material.

[0296] The energy-based damage failure criteria mainly include the BK criterion and the power exponent criterion. Since the BK criterion is generally used for interfaces with the same tangential characteristics, this model uses the BK criterion as the damage failure criterion of the improved cohesion model to calculate the equivalent failure separation displacement. This model uses the spring stiffness fracture toughness The square root of the critical damage initiation stress Set to separate the function of the logarithm of the velocity.

[0297] Step B32: Determine the normal fracture toughness of the steel and polymer interfaces Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression of

[0298] Among them, the normal fracture toughness of the interface between the steel and the polymer material is The expression is:

[0299]

[0300] Where, The first fitting parameter of the normal fracture toughness of the interface between steel and polymer material;

[0301] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0302] It is the second fitting parameter of the normal fracture toughness of the interface between steel and polymer materials.

[0303] The tangential fracture toughness of the interface between the steel and the polymer material The expression is:

[0304]

[0305] Where, It is the first fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials;

[0306] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0307] It is the second fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials.

[0308] The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is:

[0309]

[0310] Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material;

[0311] is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material;

[0312] It is the second fitting parameter of the normal critical damage initiation stress of the interface between steel and polymer materials.

[0313] The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression:

[0314]

[0315] Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material;

[0316] is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material;

[0317] It is the first fitting parameter of the critical tangential damage initiation stress at the interface between steel and polymer materials.

[0318] Step B33: Normal fracture toughness of the interface between steel and polymer material Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent failure separation displacement of the interface between the steel and the polymer material

[0319] Step C: Analyzing the ultimate load-bearing characteristics of the marine composite hose at different loading rates based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material, including the following steps:

[0320] Step C1: Based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the mixed tangential and normal damage model of the interface between the steel and the polymer material, the expressions of the normal interface stress and normal displacement of the interface between the steel and the polymer material considering the interface damage are obtained as follows:

[0321]

[0322] Where, σ n is the normal stress at a certain point on the interface between steel and polymer material;

[0323] δ nis the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension;

[0324] D(δ n ) is the interface damage value caused by the normal displacement of the interface between steel and polymer material;

[0325] is the 0th spring stiffness in the normal direction;

[0326] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0327] t is the time variable;

[0328] P1 is the number of Maxwell elements in the normal direction;

[0329] i is the Maxwell unit in one of the normal directions;

[0330] E i n is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0331] is the relaxation time of the i-th Maxwell element in the normal direction;

[0332] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t;

[0333] e is a natural constant;

[0334] It represents the stress of all Maxwell elements in the normal direction when they are under load for the total time T and are in tension, or 0 when they are in compression;

[0335] K c is the compression factor.

[0336] The expressions of tangential interface stress and tangential displacement of the steel and polymer material interface considering interface damage are obtained as follows:

[0337]

[0338] Where, σ s is the tangential stress at a certain point on the interface between steel and polymer material;

[0339] δs is the normal displacement of a point on the interface between steel and polymer material;

[0340] D(δ s ) is the interface damage value caused by the tangential displacement at the interface between steel and polymer material;

[0341] is the 0th spring stiffness in the tangential direction;

[0342] T is the total time that a certain point on the interface between steel and polymer material receives load;

[0343] t is the time variable;

[0344] P2 is the number of Maxwell elements in the normal direction;

[0345] j is the Maxwell unit in one of the tangential directions;

[0346] E i s is the stiffness of the spring of the i-th Maxwell unit in the tangential direction;

[0347] is the relaxation time of the i-th Maxwell element in the normal direction;

[0348] is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the tangential direction at time variable t;

[0349] e is a natural constant.

[0350] Step C2: Discretize the expressions of interface stress and displacement considering interface damage between the steel and polymer material to obtain discretized expressions of normal stress and displacement at the interface between the steel and polymer material and discretized expressions of tangential stress and displacement.

[0351] The discretization method is to discretize the load interval [0, T] into M time increments, that is, t m+1 =t m +Δt m .

[0352] The expressions of normal stress and displacement at the interface between steel and polymer material after discretization are:

[0353]

[0354] Where, σ n (t m+1 ) is a point on the interface between steel and polymer material at t m+1Normal stress at moment;

[0355] D m+1 is the interface damage value caused by the normal displacement of the interface between steel and polymer material at the mth time increment;

[0356] P1 is the number of Maxwell elements in the normal direction;

[0357] i is the Maxwell unit in one of the normal directions;

[0358] is the 0th spring stiffness in the normal direction;

[0359] δ n (t m+1 ) is a point on the interface between steel and polymer material at t m+1 Normal displacement at time δ n (t m ) is a point on the interface between steel and polymer material at t m Normal displacement at time t, Δt m is the displacement increment of the mth time increment;

[0360] is the relaxation time of the i-th Maxwell element in the normal direction;

[0361] E i n is the stiffness of the spring of the i-th Maxwell element in the normal direction;

[0362] e is a natural constant;

[0363] K c is the compression factor, which is the ratio of the interface stiffness during compression to the interface stiffness during tension.

[0364] in, Consider the effect of loading rate on the mechanical behavior of the interface.

[0365] The expressions of tangential stress and displacement at the interface between steel and polymer material after discretization are:

[0366]

[0367] Where σ s (t m+1 ) is a point on the interface between steel and polymer material at t m+1 Normal stress at moment;

[0368] D m+1 is the interface damage value caused by the normal displacement of the interface between steel and polymer material at the mth time increment;

[0369] P2 is the number of Maxwell elements in the tangential direction;

[0370] j is the Maxwell unit in one of the tangential directions;

[0371] is the 0th spring stiffness in the tangential direction;

[0372] δ s (t m+1 ) is a point on the interface between steel and polymer material at t m+1 The tangential displacement at time δ s (t m ) is a point on the interface between steel and polymer material at t m Tangential displacement at time t, Δt m is the displacement increment of the mth time increment;

[0373] is the relaxation time of the i-th Maxwell unit in the tangential direction;

[0374] E i s is the stiffness of the spring of the i-th Maxwell unit in the tangential direction;

[0375] e is a natural constant.

[0376] Step C3: Apply the discretized expressions of normal stress and displacement and the discretized expressions of tangential stress and displacement to analyze the ultimate bearing characteristics of the marine composite hose under different loading rates.

[0377] Based on the discretized expressions for the normal stress and displacement at the steel-polymer interface and the tangential stress and displacement at the steel-polymer interface derived above, a VUMAT or UMAT subroutine is developed. A finite element model of the marine composite hose is constructed using ABAQUS finite element software. The mechanical behavior of the steel-polymer interface is simulated using the VUMAT or UMAT subroutine, allowing analysis of the ultimate load-bearing characteristics of the marine composite hose under different loading rates.

[0378] Example 2: A device for constructing an interface mechanics model

[0379] Embodiment 2 of the present invention provides a device for constructing an interface mechanics model, comprising:

[0380] The first processing unit is used to establish a viscoelastic constitutive model of the interface between steel and polymer materials, including the stress-displacement relationship of a certain point on the interface between steel and polymer materials when subjected to normal and tangential loads;

[0381] The second processing unit is used to establish a mixed tangential and normal damage model of the interface between the steel and polymer material based on the calculation formula of the cohesive force model damage value and the stiffness, fracture toughness and critical damage initiation stress of the interface spring between the steel and polymer material;

[0382] The third processing unit is used to analyze the ultimate bearing characteristics of the marine composite hose under different load loading rates based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material.

[0383] Example 3: A computer-readable storage medium

[0384] Embodiment 3 of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the method described in embodiment 1 are implemented.

[0385] Example 4: A computer device

[0386] Embodiment 4 of the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method described in embodiment 1 when executing the computer program.

[0387] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for constructing an interface mechanics model, characterized in that: include Establish a viscoelastic constitutive model for the interface between steel and polymer materials, including the relationship between stress and displacement at a point on the interface between steel and polymer materials when subjected to normal and tangential loads; Based on the calculation formula of the cohesive force model damage value, the stiffness, fracture toughness and critical damage initiation stress of the interface spring between steel and polymer materials are used to establish a mixed tangential and normal damage model for the interface between steel and polymer materials. According to the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material, the ultimate load-bearing characteristics of the marine composite hose under different load loading rates are analyzed.

2. The method for constructing an interface mechanics model according to claim 1, wherein: The relationship between the normal stress and displacement at a certain point on the interface between the steel and the polymer material is: Where, σ n is the stress in the normal direction at a certain point on the interface between steel and polymer material, where n represents the normal direction; δ n is the normal displacement of a point on the interface between steel and polymer material, where <δ n > + Indicates that the normal displacement of the point is in tension or 0 when under compression, <δ n > - Indicates the normal displacement of the point when it is in compression or 0 when it is in tension; is the 0th spring stiffness in the normal direction; T is the total time that a certain point on the interface between steel and polymer material receives load; t is the time variable; P1 is the number of Maxwell elements in the normal direction; i is the Maxwell unit in one of the normal directions; E i n is the stiffness of the spring of the i-th Maxwell element in the normal direction; is the relaxation time of the i-th Maxwell element in the normal direction; is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t; e is a natural constant; It represents the stress of all Maxwell elements in the normal direction when they are under load for the total time T and are in tension, or 0 when they are in compression; K c is the compression factor.

3. The method for constructing an interface mechanics model according to claim 1, wherein: The relationship between the tangential stress and displacement at a certain point on the interface between the steel and the polymer material is: Where, σ s is the tangential stress at a certain point on the interface between steel and polymer material, where s represents the tangential direction; δ s is the tangential displacement of a point on the interface between steel and polymer material; is the 0th spring stiffness in the tangential direction; T is the total time that a certain point on the interface between steel and polymer material receives load; t is the time variable; P2 is the number of Maxwell elements in the tangential direction; j is the Maxwell unit in one of the tangential directions; is the stiffness of the spring of the j-th Maxwell element in the tangential direction; is the relaxation time of the i-th Maxwell unit in the tangential direction; is the first-order differential expression of the displacement of a point on the interface between steel and polymer material in the normal direction at time variable t; e is a natural constant.

4. The method for constructing an interface mechanics model according to claim 1, wherein: The establishment of a mixed tangential and normal damage model for the interface between steel and polymer material comprises the following specific steps: Step B1: Determine the calculation formula for the damage value of the cohesive force model, which is expressed as follows: Where t is the time variable; δ m is the equivalent separation displacement at a certain point on the interface between steel and polymer material; D(δ m (t)) is the equivalent interface separation displacement δ at a certain point on the interface between steel and polymer material at time t m The interface damage value caused by δ m (t) is the equivalent displacement of a point on the interface between steel and polymer material at time t; is the equivalent damage initiation separation displacement of the interface between steel and polymer material; is the equivalent failure separation displacement of the interface between steel and polymer material; Step B2: Equivalent damage initial separation displacement of the interface between the steel and the polymer material Calculation of Step B3: Equivalent failure separation displacement of the interface between the steel and the polymer material Calculation.

5. The method for constructing an interface mechanics model according to claim 4, wherein: Step B2 includes the following specific steps: Step B21: Determine the equivalent damage initial separation displacement of the interface between the steel and the polymer material The expression of the equivalent damage initiation separation displacement of the interface between the steel and the polymer material is established by this expression and the 0th spring stiffness in the normal direction The 0th spring stiffness in the tangential direction and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of Among them, the equivalent damage starting separation displacement of the interface between the steel and the polymer material is The expression is: Where, is the equivalent damage initiation separation displacement of the interface between steel and polymer material; β is the displacement composite ratio; It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only; It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load; is the 0th spring stiffness in the tangential direction of the interface between steel and polymer material; is the 0th spring stiffness in the normal direction of the interface between steel and polymer material; Step B22: Determine the zeroth spring stiffness in the normal direction of the interface between the steel and polymer materials The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression of Among them, the zeroth spring stiffness in the normal direction of the interface between the steel and the polymer material is The expression: Where, is the first fitting parameter of the normal spring stiffness of the interface between steel and polymer material; is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material; is the second fitting parameter of the normal spring stiffness of the interface between steel and polymer material; The 0th spring stiffness in the tangential direction of the interface between the steel and the polymer material The expression is: Where, is the first fitting parameter of the tangential spring stiffness of the interface between steel and polymer material; is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material; is the second fitting parameter of the tangential spring stiffness of the interface between steel and polymer material; The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is: Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material; is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material; The second fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material; The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression: Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material; is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material; The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material; Step B23: Calculate the zeroth spring stiffness in the normal direction of the interface between steel and polymer material. The 0th spring stiffness in the tangential direction of the interface between steel and polymer material and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent damage initial separation displacement of the interface between the steel and the polymer material 6. The method for constructing an interface mechanics model according to claim 4, wherein: Step B3 includes the following specific steps: Step B31: Determine the equivalent failure separation displacement of the interface between the steel and the polymer material The equivalent failure separation displacement of the interface between the steel and the polymer material is established by this expression Normal fracture toughness at the interface between steel and polymer materials Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The functional relationship of The equivalent failure separation displacement of the interface between the steel and the polymer material The expression is: Where, is the equivalent failure separation displacement of the interface between steel and polymer material; β is the displacement composite ratio; λ is the energy recombination ratio; κ is the stress composite ratio; η is the BK criterion coefficient; is the normal fracture toughness of the interface between steel and polymer material; is the tangential fracture toughness of the interface between steel and polymer material; It is the damage initiation stress when the interface between steel and polymer material is subjected to normal load only; It is the damage initiation stress when the interface between steel and polymer material is subjected to only tangential load; Step B32: Determine the normal fracture toughness of the steel and polymer interfaces Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials The expression, Among them, the normal fracture toughness of the interface between the steel and the polymer material is The expression is: Where, The first fitting parameter of the normal fracture toughness of the interface between steel and polymer material; is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material; The second fitting parameter of the normal fracture toughness of the interface between steel and polymer materials; The tangential fracture toughness of the interface between the steel and the polymer material The expression is: Where, It is the first fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials; is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material; The second fitting parameter of the tangential fracture toughness of the interface between steel and polymer materials; The critical damage initiation stress in the normal direction of the interface between the steel and the polymer material The expression is: Where, The first fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material; is the first-order differential expression of the normal displacement of a point on the interface between steel and polymer material; The second fitting parameter of the normal critical damage initiation stress at the interface between steel and polymer material; The critical damage initiation stress in the tangential direction of the interface between the steel and the polymer material The expression: Where, The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material; is the first-order differential expression of the tangential displacement of a point on the interface between steel and polymer material; The first fitting parameter of the critical damage initiation stress at the interface between steel and polymer material; Step B33: Normal fracture toughness of the interface between steel and polymer material Tangential fracture toughness of the interface between steel and polymer materials and the critical damage initiation stress in the normal direction of the interface between steel and polymer materials Critical damage initiation stress in the tangential direction of the interface between steel and polymer materials Reverse calculation of the equivalent failure separation displacement of the interface between the steel and the polymer material 7. The method for constructing an interface mechanics model according to claim 1, wherein: The analysis of the ultimate load-bearing characteristics of the marine composite hose under different load loading rates includes the following specific steps: Based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the mixed tangential and normal damage model of the interface between the steel and the polymer material, expressions for interface stress and displacement considering interface damage are obtained; Discretizing the expressions of interface stress and displacement between the steel and polymer material considering interface damage to obtain discretized expressions of normal stress and displacement and discretized expressions of tangential stress and displacement; The discretized expressions of normal stress and displacement and the discretized expressions of tangential stress and displacement are used to analyze the ultimate bearing characteristics of marine composite hoses under different loading rates.

8. A device for constructing an interface mechanics model, characterized in that: include The first processing unit is used to establish a viscoelastic constitutive model of the interface between steel and polymer materials, including the stress-displacement relationship of a certain point on the interface between steel and polymer materials when subjected to normal and tangential loads; The second processing unit is used to establish a mixed tangential and normal damage model of the interface between steel and polymer material based on the calculation formula of the cohesive force model damage value and the stiffness, fracture toughness and critical damage initiation stress of the spring at the interface between steel and polymer material; The third processing unit is used to analyze the ultimate bearing characteristics of the marine composite hose under different load loading rates based on the viscoelastic constitutive model of the interface between the steel and the polymer material and the tangential and normal mixed damage model of the interface between the steel and the polymer material.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

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