A method and device for calculating the deflection of a circular offshore inflatable beam, and an electronic device

Abstract

The application discloses a kind of offshore circular inflatable beam deflection calculation method, device and electronic equipment, the method comprises: establishing offshore circular inflatable beam model, the offshore circular inflatable beam model includes circular inflatable beam body model and sea surface foundation model;With spring model instead of sea surface foundation model to establish offshore circular inflatable beam stress state model;According to the stress parameter of offshore circular inflatable beam stress state model and the measurement parameter of circular inflatable beam body model, establish deflection theoretical calculation model;Based on the deflection theoretical calculation model, the deflection of offshore circular inflatable beam to be measured is calculated.The present application establishes simple, efficient deflection theoretical calculation model by introducing winkel hypothesis, to realize for the load deformation of offshore circular inflatable beam of floating inflatable membrane structure composition, promote the purpose of inflatable beam development.

Description

Technical Field

[0001] This invention relates to the field of inflatable beam deformation calculation, specifically to a method, apparatus, and electronic device for calculating the deflection of a marine circular inflatable beam. Background Technology

[0002] Inflatable membrane structures, as a novel material, are widely used in various fields due to their light weight, rapid deployment, and low cost. In marine engineering, particularly in maritime military transportation and disaster relief, temporary structures that are lightweight, require minimal storage and transportation space, and can be rapidly deployed and retracted are needed to meet operational or emergency requirements. Circular inflatable beams composed of inflatable membrane structures can effectively meet these requirements. However, although the prediction of membrane material properties and structural bending is now quite mature, effective analytical methods and calculation tools are lacking for the load-bearing deformation of circular inflatable beams composed of floating inflatable membrane structures in actual maritime applications, thus hindering the development of inflatable beams. Summary of the Invention

[0003] In view of this, it is necessary to propose a method, device, and electronic equipment for calculating the deflection of a circular inflatable beam at sea, so as to solve the technical problem that restricts the development of inflatable beams by the lack of effective analytical means for the load-bearing deformation capacity of circular inflatable beams composed of floating inflatable membrane structures.

[0004] To address the aforementioned problems, this invention provides a method for calculating the deflection of a circular inflatable beam at sea, comprising:

[0005] A model of a circular inflatable beam at sea is established, which includes a model of the circular inflatable beam body and a sea surface foundation model.

[0006] A spring model is used to replace the sea surface foundation model, and a stress state model of the circular inflatable beam at sea is established based on the circular inflatable beam body model and the spring model.

[0007] A deflection theoretical calculation model is established based on the force parameters of the stress state model of the circular inflatable beam at sea and the measurement parameters of the circular inflatable beam body model.

[0008] The deflection of the under-test circular inflatable beam at sea is calculated based on the aforementioned deflection theory calculation model. Further, a stress state model of the circular inflatable beam at sea is established by replacing the sea surface foundation model with a spring model, based on the circular inflatable beam body model and the spring model, including:

[0009] By introducing the Winkel assumption, the reaction force of seawater on the circular inflatable beam in the marine circular inflatable beam model is simplified to the elastic force of a uniformly distributed spring, and the equation of the proportional relationship between the reaction force and the deflection is obtained, thus obtaining the spring model.

[0010] Establish the elastic relationship equation and force relationship between the elastic coefficient of the spring model and the bending stiffness of the marine circular inflatable beam body model to obtain the force state model of the marine circular inflatable beam.

[0011] The parameters of the stress state model of the marine circular inflatable beam include seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force.

[0012] Furthermore, the measurement parameters of the circular inflatable beam model include:

[0013] The radius of the circular inflatable beam section, the length of the test position from the beam origin, the beam origin deflection, the initial rotation angle, and the beam bending stiffness.

[0014] Furthermore, the establishment of a deflection theoretical calculation model based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model includes:

[0015] Based on the stress state model of the marine circular inflatable beam, a stress balance equation is established, which consists of shear force, bending moment, reaction force, and uniformly distributed load.

[0016] Establish the transformation equations for rotation angle, bending moment, and shear force, and substitute these equations into the force equilibrium equation to obtain the differential equation of beam deflection.

[0017] Based on the aforementioned differential equation of beam deflection, proportional relationship equation, and elastic relationship equation, theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained.

[0018] The expression for the sinking area is obtained by calculating the deflection and the cross-sectional radius. The expression for the reaction force is then obtained by calculating the expression for the sinking area. The expression for the elastic coefficient is obtained by substituting the equation for the proportional relationship between the reaction force and the deflection into the expression for the reaction force.

[0019] The theoretical calculation model for deflection is obtained by combining the expression for the elastic coefficient with the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force.

[0020] Furthermore, the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force, derived from the beam deflection differential equation, proportionality equation, and elasticity equation, include:

[0021] Substituting the proportional relationship equation and the elasticity relationship equation into the beam deflection differential equation, we obtain the non-homogeneous differential equation of beam deflection.

[0022] By setting the uniformly distributed load to zero, the non-homogeneous differential equation of beam deflection is transformed into a homogeneous differential equation of beam deflection, and the general solution of the homogeneous differential equation of beam deflection is calculated.

[0023] By introducing hyperbolic functions and establishing integration constants to simplify the general solution of the homogeneous differential equation of the beam deflection, and defining the integration constants with initial parameters, the initial parameter expression equation of the deflection is obtained.

[0024] The theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained by using the initial parameter expression equation of the deflection and differential calculation.

[0025] Further, the process of calculating the expression for the sinking area based on the deflection and the cross-sectional radius, calculating the expression for the reaction force based on the expression for the sinking area, and substituting the expression for the reaction force into the equation relating the reaction force and the deflection to calculate the expression for the elastic coefficient includes:

[0026] The central angle and chord length of the circular inflatable beam section are calculated based on the radius and deflection of the circular inflatable beam section.

[0027] The expression for the sunken area is calculated based on the central angle, chord length, radius, and deflection of the circular inflatable beam section.

[0028] Based on the basic model of the sea surface, the reaction force is obtained as the product of the sinking area, the liquid density, and the gravity. The expression for the reaction force is then calculated.

[0029] Substituting the reaction force expression into the equation relating reaction force and deflection, we obtain the elastic coefficient expression.

[0030] Furthermore, the establishment of the deflection theory calculation model also includes:

[0031] By introducing Euler's beam theory, a relationship between deflection and bending stiffness is established.

[0032] The displacement of the marine circular inflatable beam under bending load is measured, and the bending stiffness is solved.

[0033] Furthermore, the calculation of the deflection of the tested circular inflatable beam at sea based on the deflection theory calculation model includes:

[0034] Obtain the measurement parameters of the circular inflatable beam under test, the density of seawater, and the acceleration due to gravity.

[0035] The measurement parameters of the circular inflatable beam to be tested, the seawater density, and the gravitational acceleration are input into the deflection theoretical calculation model;

[0036] The deflection of the circular inflatable beam under test was calculated based on the deflection theory calculation model.

[0037] On the other hand, the present invention also provides a device for calculating the deflection of a marine circular inflatable beam, comprising:

[0038] The model building unit is used to build a marine circular inflatable beam model, which includes a circular inflatable beam body model and a sea surface foundation model.

[0039] The model replacement unit replaces the sea surface foundation model with a spring model, and establishes a stress state model of the circular inflatable beam at sea based on the circular inflatable beam body model and the spring model.

[0040] The theoretical calculation unit is used to establish a deflection theoretical calculation model based on the force parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model.

[0041] The deflection calculation unit is used to calculate the deflection of the circular inflatable beam under test at sea based on the deflection theory calculation model.

[0042] On the other hand, the present invention also provides an electronic device, including a memory and a processor, wherein,

[0043] The memory is used to store programs;

[0044] The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps in the above-described method for calculating the deflection of a marine circular inflatable beam.

[0045] Compared with existing technologies, the beneficial effects of this invention include: First, a marine circular inflatable beam model is established, comprising a circular inflatable beam body model and a sea surface foundation model. Then, a spring model replaces the sea surface foundation model, and a stress state model of the marine circular inflatable beam is established based on the circular inflatable beam body model and the spring model. This stress state model includes seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force. A deflection theoretical calculation model is established based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model. Finally, the deflection of the marine circular inflatable beam under test is calculated based on the deflection theoretical calculation model. This invention introduces the Winkel assumption to establish a simple and efficient deflection theoretical calculation model, and calculates the deflection, rotation angle, bending moment, and shear force of the marine circular inflatable beam based on this model. This achieves effective analysis of the load-bearing deformation of marine circular inflatable beams composed of floating inflatable membrane structures, thus promoting the development of inflatable beams. Attached Figure Description

[0046] Figure 1 A flowchart illustrating an embodiment of the method for calculating the deflection of a circular inflatable beam at sea provided by the present invention;

[0047] Figure 2 For the present invention Figure 1A flowchart illustrating an embodiment of S102;

[0048] Figure 3 This is a schematic diagram of the stress state model of a marine circular inflatable beam according to an embodiment of the present invention;

[0049] Figure 4 This is a differential analysis diagram of a marine circular inflatable beam according to an embodiment of the present invention;

[0050] Figure 5 This is a cross-sectional schematic diagram of a marine circular inflatable beam according to an embodiment of the present invention;

[0051] Figure 6 This is a schematic diagram of the forces acting on a freely floating circular inflatable beam at sea under two symmetrical concentrated loads, according to an embodiment of the present invention.

[0052] Figure 7 This is a simplified diagram of the forces acting on a four-point bending beam according to an embodiment of the present invention;

[0053] Figure 8 A schematic diagram of the marine circular inflatable beam deflection calculation device provided by the present invention;

[0054] Figure 9 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0055] 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 a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0056] This invention provides a method, apparatus, and electronic device for calculating the deflection of a circular inflatable beam at sea, which will be described below.

[0057] Figure 1 The method for calculating the deflection of a circular inflatable beam at sea provided by this invention, such as Figure 1 As shown, the method for calculating the deflection of a circular inflatable beam at sea includes:

[0058] S101. Establish a marine circular inflatable beam model, which includes a circular inflatable beam body model and a sea surface foundation model.

[0059] S102. Replace the sea surface foundation model with a spring model, and establish a stress state model of the circular inflatable beam at sea based on the circular inflatable beam body model and the spring model.

[0060] S103. Establish a deflection theoretical calculation model based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model.

[0061] S104. Calculate the deflection of the circular inflatable beam under test at sea based on the deflection theory calculation model.

[0062] It should be noted that deflection refers to the linear displacement of the axis of a member in a direction perpendicular to the axis, or the linear displacement of the mid-surface of a plate or shell in a direction perpendicular to the mid-surface, under stress or non-uniform temperature changes. In the embodiments of this invention, deflection specifically refers to the degree of deformation of a circular inflatable beam under load, thereby enabling quantitative analysis of the load-bearing deformation of a marine circular inflatable beam.

[0063] Compared with existing technologies, this invention first establishes a marine circular inflatable beam model, which includes a circular inflatable beam body model and a sea surface foundation model. Then, a spring model replaces the sea surface foundation model, and a stress state model of the marine circular inflatable beam is established based on the circular inflatable beam body model and the spring model. This stress state model includes seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force. A deflection theoretical calculation model is established based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model. Finally, the deflection of the marine circular inflatable beam under test is calculated based on the deflection theoretical calculation model. This invention introduces the Winkler assumption to establish a simple and efficient deflection theoretical calculation model, and calculates the deflection, rotation angle, bending moment, and shear force of the marine circular inflatable beam based on this model. This achieves effective analysis of the load-bearing deformation of marine circular inflatable beams composed of floating inflatable membrane structures, thus promoting the development of inflatable beams.

[0064] In a specific embodiment of the present invention, a spring model is used instead of the sea surface foundation model. A stress state model of the circular inflatable beam at sea is established based on the circular inflatable beam body model and the spring model, including:

[0065] By introducing the Winkel assumption, the reaction force of seawater on the circular inflatable beam in the marine circular inflatable beam model is simplified to the elastic force of a uniformly distributed spring, and the equation of the proportional relationship between the reaction force and the deflection is obtained, thus obtaining the spring model.

[0066] Establish the elastic relationship equation and force relationship between the elastic coefficient of the spring model and the bending stiffness of the marine circular inflatable beam body model to obtain the force state model of the marine circular inflatable beam.

[0067] The parameters of the stress state model of the marine circular inflatable beam include seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force.

[0068] It should be noted that the Winkel assumption assumes that the pressure on any point on the foundation is proportional to the foundation settlement deformation at that point. In the context of marine environments, this theory simplifies seawater into a series of independent springs.

[0069] Specifically, in establishing the stress state model of a circular inflatable beam at sea, to simplify the model, the Winkler assumption is introduced. The reaction force of seawater on the circular inflatable beam is simplified to a spring model composed of a series of uniformly distributed springs. The reaction force at each point is proportional to the beam's deflection, with the proportionality constant being the spring constant k. The deformation of the spring is the deflection ω(x) of the circular inflatable beam, thus obtaining the equation for the proportional relationship between the reaction force p(x) and the deflection:

[0070] p(x)=kω(x)

[0071] Meanwhile, to represent the relationship between the elastic coefficient of the spring model and the stiffness of the inflatable beam in the marine liquid foundation model, and to simplify the calculation process, an elastic relationship equation is established between the elastic coefficient k and the bending stiffness EI of the inflatable beam:

[0072]

[0073] Where α is the proportionality coefficient, and in the bending stiffness EI of the inflatable beam, E is the elastic modulus of the inflatable beam, and I is the moment of inertia of the section.

[0074] Based on the simplified representation of the spring model and the main body model of the marine circular inflatable beam, and by analyzing the force relationships within them, a force state model of the marine circular inflatable beam is derived.

[0075] In a specific embodiment of the present invention, the measurement parameters of the circular inflatable beam body model include:

[0076] The radius of the circular inflatable beam section, the length of the test position from the beam origin, the beam origin deflection, the initial rotation angle, and the beam bending stiffness.

[0077] Specifically, in the process of calculating the deflection of a circular inflatable beam at sea, the following parameters of the circular inflatable beam need to be measured: the radius of the circular inflatable beam section, the length of the measured position from the beam origin, the deflection at the beam origin, the initial rotation angle, and the beam's bending stiffness. These measured parameters are then substituted into the deflection theoretical calculation model to calculate and solve for the deflection of the circular inflatable beam at sea.

[0078] In specific embodiments of the present invention, such as Figure 2 As shown, a deflection theoretical calculation model is established based on the force parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model, including:

[0079] S201. Based on the stress state model of the marine circular inflatable beam, establish a stress balance equation, which consists of shear force, bending moment, reaction force and uniformly distributed load.

[0080] S202. Establish the transformation equations for rotation angle, bending moment, and shear force, and substitute these equations into the force equilibrium equation to obtain the differential equation of beam deflection.

[0081] S203. Based on the aforementioned beam deflection differential equation, proportional relationship equation, and elastic relationship equation, the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained.

[0082] S204. The expression for the sinking area is obtained by calculating the deflection and the cross-sectional radius. The expression for the reaction force is obtained by calculating the expression for the sinking area. The expression for the elastic coefficient is obtained by substituting the equation for the proportional relationship between the reaction force and the deflection into the expression for the reaction force.

[0083] S205. The expression for the elastic coefficient and the theoretical calculation formulas for deflection, rotation angle, bending moment and shear force are combined to obtain the theoretical calculation model for deflection.

[0084] Specifically, Figure 3 This is a schematic diagram of the stress state model of a marine circular inflatable beam according to an embodiment of the present invention, as shown below. Figure 3 As shown, Q is the shear force that causes the inflatable beam to deform, q(x) represents the uniformly distributed load acting on the inflatable beam, ω is the deflection of the inflatable beam, k is the elastic deformation of the spring, and x is the length of the position of the inflatable beam where the deflection to be calculated is from the origin of the beam.

[0085] Figure 4 This is a differential analysis diagram of a marine circular inflatable beam according to an embodiment of the present invention, as shown below. Figure 4 As shown, M is the bending moment and d represents the deformation proportionality coefficient. It is a corner.

[0086] according to Figure 3 Given the force state, establish the force equilibrium equation:

[0087]

[0088] Establish the equations for the transformation of rotation angle, bending moment, and shear force:

[0089]

[0090]

[0091]

[0092] Substituting the conversion equations of rotation angle, bending moment, and shear force into the force equilibrium equation, we obtain the beam deflection differential equation relating the length of the measured point from the beam origin to the deflection:

[0093]

[0094] Based on the differential equation of beam deflection, the proportionality equation, and the elasticity equation, the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained by calculation and solution:

[0095]

[0096]

[0097]

[0098]

[0099] Where, ω0, These are the deflection and rotation angle at the beam origin, respectively. x B x C x D x The notation introduced is obtained according to the following equation:

[0100] A(α,x)=chαxcosαx=A x

[0101]

[0102]

[0103]

[0104] At this point, to solve the theoretical calculation formula, it is necessary to establish the relationship between the parameters to be solved (deflection, rotation angle, bending moment, and shear force) and the elastic coefficient k. According to Winkler's assumption, the reaction force at each point is proportional to the deflection of the beam, and the proportionality constant is the elastic coefficient k of the spring. Therefore, the relationship between deflection and elastic coefficient can be obtained through the reaction force as a medium.

[0105] The expression for the subsidence area is obtained by calculating the deflection and the cross-sectional radius:

[0106]

[0107] Where r is the radius of the cross section.

[0108] The expression for the reaction force is derived from the expression for the subsidence area:

[0109]

[0110] Where ρ is the density at sea and g is the gravitational acceleration.

[0111] Substituting the equation relating reaction force to deflection into the expression for reaction force, we obtain the expression for the elastic coefficient:

[0112]

[0113] At this point, by combining the expression for the elastic coefficient with the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force, a theoretical calculation model for deflection can be obtained.

[0114] In a specific embodiment of the present invention, theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained based on the beam deflection differential equation, proportionality equation, and elasticity equation, including:

[0115] Substituting the proportional relationship equation and the elasticity relationship equation into the beam deflection differential equation, we obtain the non-homogeneous differential equation of beam deflection.

[0116] By setting the uniformly distributed load to zero, the non-homogeneous differential equation of beam deflection is transformed into a homogeneous differential equation of beam deflection, and the general solution of the homogeneous differential equation of beam deflection is calculated.

[0117] By introducing hyperbolic functions and establishing integration constants to simplify the general solution of the homogeneous differential equation of the beam deflection, and defining the integration constants with initial parameters, the initial parameter expression equation of the deflection is obtained.

[0118] The theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained by using the initial parameter expression equation of the deflection and differential calculation.

[0119] Specifically, in obtaining the theoretical calculation formula, the proportional relationship equation and the elastic relationship equation are first substituted into the differential equation of the deflection beam, resulting in:

[0120]

[0121] To solve the equation, we replace x with αx, resulting in a fourth-order nonhomogeneous differential equation:

[0122]

[0123] The solution to a fourth-order nonhomogeneous differential equation is the sum of the general solution and the particular solution.

[0124] Setting the uniformly distributed load q(x) to 0, we obtain the homogeneous differential equation:

[0125]

[0126] And the general solution of the homogeneous differential equation is obtained:

[0127] ω(x)=e αx(A1cosαx+A2sinαx)+e -αx (A3cosαx+A4sinαx)

[0128] Introducing hyperbolic functions:

[0129] e αx =chαx+shαx,e -αx chαx-shαx

[0130] And let:

[0131]

[0132]

[0133] Where A1, A2, A3, A4 and B1, B2, B3, B4 are defined integration constants, and the general solution of the homogeneous differential equation is transformed into:

[0134] ω(x)=B1chαxcosαx+B2chαxsinαx+B3shαxcosαx

[0135] +B4shαxsinαx

[0136] By defining the integration constant in the equation using initial parameters, and substituting x = 0 into the general solution of the homogeneous differential equation, we obtain:

[0137] ω(x)| x＝0 =ω0=B1

[0138]

[0139]

[0140]

[0141] Where, ω0, M0 and Q0 are the deflection, rotation, bending moment, and shear force at the origin of the beam, respectively. The initial parameter representation of the integration constant is obtained by solving for these parameters.

[0142] B1=ω0

[0143]

[0144]

[0145]

[0146] Furthermore, substituting into the general solution of the homogeneous differential equation, we obtain the initial parameter representation of the deflection:

[0147]

[0148] Introduction notation A x B x C x D x At the same time, based on the elasticity equation, using Instead of EI, the initial parameter representation of deflection is simplified to:

[0149]

[0150] Furthermore, the theoretical formulas for calculating deflection, rotation angle, bending moment, and shear force are obtained through differential calculations:

[0151]

[0152]

[0153]

[0154]

[0155] In a specific embodiment of the present invention, the expression for the sinking area is calculated based on the deflection and the cross-sectional radius; the expression for the reaction force is calculated based on the expression for the sinking area; and the expression for the reaction force is substituted into the equation relating the reaction force and the deflection to calculate the expression for the elastic coefficient, including:

[0156] The central angle and chord length of the circular inflatable beam section are calculated based on the radius and deflection of the circular inflatable beam section.

[0157] The expression for the sunken area is calculated based on the central angle, chord length, radius, and deflection of the circular inflatable beam section.

[0158] Based on the basic model of the sea surface, the reaction force is obtained as the product of the sinking area, the liquid density, and the gravity. The expression for the reaction force is then calculated.

[0159] Substituting the reaction force expression into the equation relating reaction force and deflection, we obtain the elastic coefficient expression.

[0160] Specifically, Figure 5 A schematic diagram of the cross-section of a circular inflatable beam at sea, as shown below. Figure 5 As shown, r is the radius of the cross section, b is the chord length of the sunken area, θ is half of the central angle, and ω(x) is the deflection of the inflatable beam at that location.

[0161] The subsidence area can be expressed as:

[0162]

[0163] Furthermore, the central angle θ and chord length b can be expressed in terms of radius r and deflection ω(x), yielding the sunken area as follows:

[0164]

[0165] Based on the sea surface model, the reaction force is actually the buoyancy of the sea on the circular inflatable beam. Therefore, the reaction force at each point of the inflatable beam is the product of the submerged area, the liquid density, and the weight.

[0166]

[0167] Substituting these values ​​into the equation relating reaction force and deflection, we obtain the expression for the elastic coefficient:

[0168]

[0169] In a specific embodiment of the present invention, establishing a deflection theoretical calculation model further includes:

[0170] By introducing Euler's beam theory, a relationship between deflection and bending stiffness is established.

[0171] The displacement of the marine circular inflatable beam under bending load is measured, and the bending stiffness is solved.

[0172] Specifically, in order to more effectively solve the relationship between the elastic coefficient k and the proportional coefficient α, it is also necessary to solve the bending stiffness EI of the beam.

[0173] Specifically, in the embodiments of the present invention, to solve the bending stiffness EI of the beam, the relationship between the mid-span deflection and the bending stiffness of the beam is first established by introducing Euler's beam theory. Then, the displacement of the beam under external load is measured by a four-point bending experiment, and the bending stiffness is then solved.

[0174] It should be noted that Euler's beam theory is an important equation in engineering mechanics and classical beam mechanics. Simplified linear elasticity theory is used to calculate the stress and deformation characteristics of beams. The four-point bending test is a test method for measuring the bending properties of materials. The strip specimen to be tested is placed flat in the bending test fixture to form a simply supported beam. The distance between the two lower support points supporting the specimen is adjustable according to the specimen length. There are two symmetrical loading points on the top of the specimen.

[0175] In a specific embodiment of the present invention, the deflection of the tested circular inflatable beam at sea is calculated based on the deflection theory calculation model, including:

[0176] Obtain the measurement parameters of the circular inflatable beam under test, the density of seawater, and the acceleration due to gravity.

[0177] The measurement parameters of the circular inflatable beam to be tested, the seawater density, and the gravitational acceleration are input into the deflection theoretical calculation model;

[0178] The deflection of the circular inflatable beam under test was calculated based on the deflection theory calculation model.

[0179] Specifically, taking a freely floating circular inflatable beam at sea subjected to two symmetrical concentrated loads as an example, such as... Figure 6 As shown, solve for the deflection at mid-span.

[0180] Obtain the measurement parameters of the circular inflatable beam to be tested, including: the bending stiffness EI of the beam, the cross-sectional radius r, the length l from the test position to the origin of the beam, the density of seawater ρ, and the gravitational acceleration g.

[0181] Substituting x = l into the theoretical calculation model, we get:

[0182]

[0183] For the initial displacement parameter ω0 and the initial rotation angle Because the load on the inflatable beam is symmetrical about the mid-span, the mid-span rotation angle... and shear force Q l Find:

[0184]

[0185]

[0186] The initial displacement parameter ω0 and the initial rotation angle can be obtained by simplification. for:

[0187]

[0188]

[0189] Substituting the initial displacement parameters and initial rotation angle, the deflection can be obtained as follows:

[0190]

[0191] at the same time, Figure 7 A simplified diagram of the forces acting on a beam undergoing bending at four points, as shown below. Figure 7 As shown, l α l b l s Let F be the length of the beam, F be the external load, and ω be the deflection of the beam. According to Euler's beam theory, we can obtain:

[0192]

[0193] The displacement of the beam under bending load was measured by a four-point bending test, and the bending stiffness was solved.

[0194] By combining the expressions for bending stiffness and elastic coefficient, the mid-span deflection ω of a freely floating circular inflatable beam at sea subjected to two symmetrical concentrated loads can be calculated.l .

[0195] To better implement the deflection calculation method for a circular inflatable beam at sea in this embodiment of the invention, correspondingly, this embodiment of the invention also provides a deflection calculation device for a circular inflatable beam at sea, such as... Figure 8 As shown, the marine circular inflatable beam deflection calculation device 800 includes:

[0196] Model building unit 801 is used to build a marine circular inflatable beam model, which includes a circular inflatable beam body model and a sea surface foundation model.

[0197] Model replacement unit 802 replaces the sea surface foundation model with a spring model and establishes a stress state model of the circular inflatable beam at sea based on the circular inflatable beam body model and the spring model.

[0198] The theoretical calculation unit 803 is used to establish a deflection theoretical calculation model based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model.

[0199] The deflection calculation unit 804 is used to calculate the deflection of the circular inflatable beam under test at sea based on the deflection theory calculation model.

[0200] The marine circular inflatable beam deflection calculation device 800 described in the above embodiments can realize the technical solutions described in the above embodiments of the marine circular inflatable beam deflection calculation method. The specific implementation principles of each module or unit can be found in the corresponding content of the above embodiments of the marine circular inflatable beam deflection calculation method, and will not be repeated here.

[0201] Based on the method for calculating the deflection of a circular inflatable beam at sea, this invention also provides an electronic device, such as... Figure 9 As shown, Figure 9 This is a schematic diagram of an embodiment of the electronic device provided by the present invention. The electronic device 900 includes a processor 901, a memory 902, and a computer program stored in the memory 902 and executable on the processor 901. When the processor 901 executes the program, it implements the deflection calculation method for a circular inflatable beam at sea as described above.

[0202] In a preferred embodiment, the electronic device 900 may further include a display 903 for displaying the processor 901 performing the optimal shifting calculation method for the roll-on / roll-off ship terminal as described above.

[0203] The processor 901 may be an integrated circuit chip with signal processing capabilities. The processor 901 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it can also be a Digital Signal Processor (DSP) or an Application Specific Integrated Circuit (ASIC). It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor can also be a microprocessor or any conventional processor.

[0204] The memory 902 can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Secure Digital (SD card), Flash Card, etc. The memory 902 stores programs, and the processor 901 executes these programs upon receiving execution instructions. The process definition methods disclosed in any of the foregoing embodiments of the present invention can be applied to the processor 901, or implemented by the processor 901.

[0205] The display 903 can be an LED display, an LCD display, or a touch screen display, etc. The display 903 is used to display various information from the electronic device 900.

[0206] Understandable, Figure 9 The structure shown is only a schematic diagram of one possible structure of electronic device 900. Electronic device 900 may also include more than one of the following: Figure 9 Show more or fewer components. Figure 9 The components shown can be implemented using hardware, software, or a combination thereof.

[0207] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for calculating the deflection of a circular inflatable beam at sea, characterized in that, include: A model of a circular inflatable beam at sea is established, which includes a model of the circular inflatable beam body and a sea surface foundation model. A spring model is used to replace the sea surface foundation model. Based on the circular inflatable beam body model and the spring model, a stress state model of the circular inflatable beam at sea is established. This includes: introducing the Winkler assumption to simplify the reaction force of seawater on the circular inflatable beam in the model to the elastic force of a uniformly distributed spring, obtaining the equation of proportional relationship between reaction force and deflection, thus obtaining the spring model; establishing the elastic relationship equation and the force relationship between the elastic coefficient of the spring model and the bending stiffness of the inflatable beam in the model of the circular inflatable beam at sea, thus obtaining the stress state model of the circular inflatable beam at sea; wherein, the parameters of the stress state model of the circular inflatable beam at sea include seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force; A deflection theoretical calculation model is established based on the force parameters of the stress state model of the circular inflatable beam at sea and the measurement parameters of the circular inflatable beam body model. The deflection of the circular inflatable beam under test at sea is calculated based on the aforementioned deflection theory calculation model.

2. The method for calculating the deflection of a marine circular inflatable beam according to claim 1, characterized in that, The measurement parameters of the circular inflatable beam model include: The radius of the circular inflatable beam section, the length of the test position from the beam origin, the beam origin deflection, the initial rotation angle, and the beam bending stiffness.

3. The method for calculating the deflection of a marine circular inflatable beam according to claim 2, characterized in that, The deflection theoretical calculation model is established based on the stress parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model, including: Based on the stress state model of the marine circular inflatable beam, a stress balance equation is established, which consists of shear force, bending moment, reaction force, and uniformly distributed load. Establish the transformation equations for rotation angle, bending moment, and shear force, and substitute these equations into the force equilibrium equation to obtain the differential equation of beam deflection. Based on the aforementioned differential equation of beam deflection, proportional relationship equation, and elastic relationship equation, theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained. The expression for the sinking area is obtained by calculating the deflection and the cross-sectional radius. The expression for the reaction force is then obtained by calculating the expression for the sinking area. The expression for the elastic coefficient is obtained by substituting the equation for the proportional relationship between the reaction force and the deflection into the expression for the reaction force. The theoretical calculation model for deflection is obtained by combining the expression for the elastic coefficient with the theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force.

4. The method for calculating the deflection of a marine circular inflatable beam according to claim 3, characterized in that, The theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force, derived from the beam deflection differential equation, proportionality equation, and elasticity equation, include: Substituting the proportional relationship equation and the elasticity relationship equation into the beam deflection differential equation, we obtain the non-homogeneous differential equation of beam deflection. By setting the uniformly distributed load to zero, the non-homogeneous differential equation of beam deflection is transformed into a homogeneous differential equation of beam deflection, and the general solution of the homogeneous differential equation of beam deflection is calculated. By introducing hyperbolic functions and establishing integration constants to simplify the general solution of the homogeneous differential equation of the beam deflection, and defining the integration constants with initial parameters, the initial parameter expression equation of the deflection is obtained. The theoretical calculation formulas for deflection, rotation angle, bending moment, and shear force are obtained by using the initial parameter expression equation of the deflection and differential calculation.

5. The method for calculating the deflection of a marine circular inflatable beam according to claim 3, characterized in that, The process involves calculating the expression for the sinking area based on the deflection and the cross-sectional radius, calculating the expression for the reaction force based on the expression for the sinking area, and substituting the expression for the reaction force into the equation relating the reaction force and the deflection to calculate the expression for the elastic coefficient, including: The central angle and chord length of the circular inflatable beam section are calculated based on the radius and deflection of the circular inflatable beam section. The expression for the sunken area is calculated based on the central angle, chord length, radius, and deflection of the circular inflatable beam section. Based on the basic model of the sea surface, the reaction force is obtained as the product of the sinking area, the liquid density, and the gravity. The expression for the reaction force is then calculated. Substituting the reaction force expression into the equation relating reaction force and deflection, we obtain the elastic coefficient expression.

6. The method for calculating the deflection of a marine circular inflatable beam according to claim 1, characterized in that, The establishment of the deflection theory calculation model also includes: By introducing Euler's beam theory, a relationship between deflection and bending stiffness is established. The displacement of the marine circular inflatable beam under bending load is measured, and the bending stiffness is solved.

7. The method for calculating the deflection of a marine circular inflatable beam according to claim 1, characterized in that, The calculation of the deflection of the circular inflatable beam under test at sea based on the deflection theory calculation model includes: Obtain the measurement parameters of the circular inflatable beam under test, the density of seawater, and the acceleration due to gravity. The measurement parameters of the circular inflatable beam to be tested, the seawater density, and the gravitational acceleration are input into the deflection theoretical calculation model; The deflection of the circular inflatable beam under test was calculated based on the deflection theory calculation model.

8. A device for calculating the deflection of a circular inflatable beam at sea, characterized in that, include: The model building unit is used to build a marine circular inflatable beam model, which includes a circular inflatable beam body model and a sea surface foundation model. The model replacement unit replaces the sea surface foundation model with a spring model. Based on the circular inflatable beam body model and the spring model, a stress state model of the circular inflatable beam at sea is established. This includes: introducing the Winkler assumption to simplify the reaction force of seawater on the circular inflatable beam in the model to the elastic force of a uniformly distributed spring, obtaining the equation relating the reaction force to the deflection, thus obtaining the spring model; establishing the elastic coefficient of the spring model and the bending stiffness of the inflatable beam in the model, as well as the stress relationship, to obtain the stress state model of the circular inflatable beam at sea; wherein the parameters of the stress state model of the circular inflatable beam at sea include seawater density, gravitational acceleration, uniformly distributed load, reaction force, and shear force. The theoretical calculation unit is used to establish a deflection theoretical calculation model based on the force parameters of the marine circular inflatable beam stress state model and the measurement parameters of the circular inflatable beam body model. The deflection calculation unit is used to calculate the deflection of the circular inflatable beam under test at sea based on the deflection theory calculation model.

9. An electronic device, characterized in that, Including memory and processor, among which, The memory is used to store programs; The processor, coupled to the memory, is used to execute the program stored in the memory to implement the steps in the offshore circular inflatable beam deflection calculation method according to any one of claims 1 to 7.

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