Large-span stiff skeleton arch rib temperature field analysis method, system, equipment and medium

Abstract

The invention belongs to the technical field of bridge engineering simulation, and relates to an actually measured data-based ultra-large-span stiff skeleton arch rib temperature field refined analysis method, system, equipment and medium. The method specifically comprises the steps of obtaining arch rib structure surface wind speed according to a canyon wind speed correction coefficient, a structure surface wind speed correction coefficient and a bridge site observation station actually measured wind speed; obtaining a convective heat transfer coefficient of the arch rib structure at the bridge site according to the surface wind speed of the arch rib structure; acquiring a cosine value of an included angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographic angle, and analyzing the direct sunlight action on the surface of the arch rib structure, so as to acquire direct radiation intensity, scattered radiation intensity, reflected radiation intensity and solar radiation heat flux density in a direct sunlight action area; based on the convective heat transfer coefficient and the solar radiation flow density, temperature field simulation is conducted on the large-span stiff framework arch rib temperature field, and arch rib temperature distribution is obtained. According to the method, the temperature distribution rule of the arch rib structure can be truly reflected.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering simulation, and specifically to a method, system, device, and medium for analyzing the temperature field of a long-span stiffening skeleton arch rib. Background Art

[0002] In recent years, long-span concrete-filled steel tube arch bridges and concrete arch bridges with them as stiffening skeletons have been widely used in the railway construction of "V"-shaped and "U"-shaped canyon terrains in mountainous areas of China due to their excellent mechanical properties and construction advantages. The structural displacement of long-span concrete-filled steel tube arch bridges is significantly correlated with the change of bridge temperature. During the construction process of the stiffening skeleton concrete arch rib, the uneven change of the structural temperature field in the time and space scales will be caused due to the changes of environmental factors such as solar radiation, temperature, and wind speed, and then significant temperature effects will be generated. The diseases caused thereby, such as the hollowing of the concrete inside the steel tube, the cracks in the outer concrete, and the bond slip, cannot be ignored for the influence on the construction stability of the bridge.

[0003] The structure of the super-long-span stiffening skeleton arch rib is complex, and its spatial position distribution along the line mileage and vertical elevation is relatively wide. The thermal boundary conditions at different positions of the arch axis are strongly correlated with factors such as environmental temperature and the solar trajectory. The existing bridge temperature fields are mainly studied by methods such as model tests, theoretical derivations, finite element numerical simulations, and on-site measurements. The model test method has the advantage of high accuracy, but the test period is relatively long. In the face of the differences in climate characteristics of different bridge site areas, the application of traditional temperature and solar radiation theoretical models in the numerical simulation of the temperature field often has a large difference from the actual structural temperature distribution. In addition, although on-site measurements can obtain the real temperature at the structural measurement point positions, due to the limitation of the number of measurement points arranged, the test results are often difficult to comprehensively reflect the temperature distribution characteristics of the overall structure, and problems such as instrument failures and data missing will inevitably occur during the test period, making it difficult to capture the temperature field at the most unfavorable moment. Summary of the Invention

[0004] The purpose of the present invention is to provide a method, system, device, and medium for analyzing the temperature field of a long-span stiffening skeleton arch rib, so as to solve the problem that it is difficult to accurately characterize the temperature field distribution of a proposed railway arch bridge in alpine canyon areas.

[0005] The present invention is achieved through the following technical solutions:

[0006] In a first aspect, a method for analyzing the temperature field of a long-span stiffening skeleton arch rib is proposed, including the following steps: obtaining a canyon wind speed correction coefficient and a structural surface wind speed correction coefficient; obtaining the measured wind speed at the bridge site observation station; obtaining the wind speed on the surface of the arch rib structure according to the canyon wind speed correction coefficient, the structural surface wind speed correction coefficient, and the measured wind speed at the bridge site observation station; obtaining the convective heat transfer coefficient of the arch rib structure at the bridge site according to the wind speed on the surface of the arch rib structure; obtaining the geographical angles required for solar radiation; obtaining the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographical angles; analyzing the direct solar radiation effect on the surface of the arch rib structure according to the cosine value to obtain the area of the arch rib structure affected by direct solar radiation; obtaining the direct radiation intensity, diffuse radiation intensity, and reflected radiation intensity within the area affected by direct solar radiation; obtaining the solar radiation heat flux density within the area affected by direct solar radiation according to the direct radiation intensity, the diffuse radiation intensity, and the reflected radiation intensity; performing temperature field simulation on the temperature field of the long-span stiffening skeleton arch rib based on the convective heat transfer coefficient and the solar radiation flux density to obtain the arch rib temperature distribution.

[0007] In a second aspect, a system for analyzing the temperature field of a long-span stiffening skeleton arch rib is proposed, including: a correction coefficient acquisition module for obtaining a canyon wind speed correction coefficient and a structural surface wind speed correction coefficient; a measured data acquisition module for obtaining the measured wind speed at the bridge site observation station; a wind field numerical simulation module for obtaining the wind speed on the surface of the arch rib structure according to the canyon wind speed correction coefficient, the structural surface wind speed correction coefficient, and the measured wind speed at the bridge site observation station; a heat transfer coefficient acquisition module for obtaining the convective heat transfer coefficient of the arch rib structure at the bridge site according to the wind speed on the surface of the arch rib structure; a geographical angle acquisition module for obtaining the geographical angles required for solar radiation; a trigonometric function calculation module for obtaining the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographical angles; a direct solar radiation analysis module for analyzing the direct solar radiation effect on the surface of the arch rib structure according to the cosine value to obtain the area of the arch rib structure affected by direct solar radiation; a radiation intensity acquisition module for obtaining the direct radiation intensity, diffuse radiation intensity, and reflected radiation intensity within the area affected by direct solar radiation; a heat flux density acquisition module for obtaining the solar radiation heat flux density within the area affected by direct solar radiation according to the direct radiation intensity, the diffuse radiation intensity, and the reflected radiation intensity; a temperature field simulation module for performing temperature field simulation on the temperature field of the long-span stiffening skeleton arch rib based on the convective heat transfer coefficient and the solar radiation flux density to obtain the arch rib temperature distribution.

[0008] In a third aspect, a computer device is provided, which includes a memory, a processor, and a transceiver that are communicatively connected in sequence. Among them, the memory is used to store computer programs, the transceiver is used to transmit and receive data, and the processor is used to read the computer programs and execute a method for analyzing the temperature field of a long-span stiffening frame arch rib as described in the first aspect.

[0009] In a fourth aspect, a computer-readable storage medium is provided. Instructions are stored on the computer-readable storage medium. When the instructions are run on a computer, a method for analyzing the temperature field of a long-span stiffening frame arch rib as described in the first aspect is executed.

[0010] In a fifth aspect, a computer program product including instructions is proposed. When the instructions are run on a computer, the computer is made to execute a method for analyzing the temperature field of a long-span stiffening frame arch rib as described in the first aspect; the computer includes: a general-purpose computer, a special-purpose computer, or a programmable device.

[0011] Compared with the prior art, the present invention has the following advantages and beneficial effects: The uneven distribution of the convective heat transfer coefficient and the shading effect of solar radiation are considered, and accurate analysis of the temperature field of a long-span stiffening frame arch bridge is achieved through simulation. Specifically, on the one hand, based on the measured environmental temperature, wind speed, and spatial position information, the convective heat transfer coefficient of the arch rib structure is corrected, and a correction model for the convective heat transfer coefficient of the structural cross-section under the influence of different wind speeds is proposed; on the other hand, the total solar radiation intensity on the surface of the structure is corrected through a shading algorithm; on this basis, a refined finite element model of the temperature field of a long-span stiffening frame arch bridge under the combined influence of various environmental factors is established, and the temperature distribution law of the arch rib structure is realistically reflected through simulation. Description of the Drawings

[0012] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, form a part of this application, and do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0013] Figure 1 It is a schematic flow chart of a method for analyzing the temperature field of a long-span stiffening frame arch rib provided by an embodiment of the present invention;

[0014] Figure 2 It is a schematic diagram of the generation principle of the three-dimensional terrain surface at the bridge site provided by an embodiment of the present invention;

[0015] Figure 3 It is a schematic diagram of the exponential wind profile at the inlet of the computational domain provided by an embodiment of the present invention;

[0016] Figure 4 It is a schematic diagram of the cross-section structure of the main arch ring and the correction area of the convective heat transfer coefficient provided by an embodiment of the present invention;

[0017] Figure 5 Schematic diagram of the geographical angular spatial position required for solar radiation calculation provided by an embodiment of the present invention;

[0018] Figure 6 Schematic diagram of the principle of the shadow occlusion algorithm provided by an embodiment of the present invention;

[0019] Figure 7 Schematic diagram of the temperature field boundary conditions of a super-long-span stiffening skeleton arch bridge provided by an embodiment of the present invention. Detailed implementation manners

[0020] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with embodiments. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and do not limit the present invention. The following described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0021] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is obvious to those of ordinary skill in the art that the present invention does not have to adopt these specific details. In other embodiments, well-known structures, materials or methods are not specifically described in order to avoid obscuring the present invention. The materials, instruments and reagents used in the following embodiments can be obtained from commercial sources unless otherwise specified. The technical means used in the embodiments are conventional means well-known to those skilled in the art unless otherwise specified.

[0022] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more unless otherwise specifically defined.

[0023] Embodiment:

[0024] In a first aspect, a method for analyzing the temperature field of a large-span stiffening skeleton arch rib is proposed, including Figure 1 The following steps shown:

[0025] Step 1: Obtain the elevation data of the terrain at the bridge site and generate a three-dimensional terrain surface according to the elevation data.

[0026] Specifically, elevation data of the terrain at the bridge site is collected through an open-source digital elevation model dataset. The collected elevation data is input into map processing software and 3D software to generate a 3D terrain surface that can be used for computational fluid dynamics analysis. The principle of Step 1 can be referred to Figure 2 . The elevation data collected through the ASTER GDEM V003 dataset can be presented in the form of a numerical elevation topographic map. The elevation data is input into Global Mapper and CATIA for coordinate system conversion and image segmentation to generate a topographic map of the bridge site area (such as a topographic map of a 5-km range near the bridge site), and then the corresponding 3D terrain surface is reversely generated from the topographic map of the bridge site area through point cloud data processing.

[0027] Step 2: Set the computational domain, import the computational domain into computational fluid dynamics software for mesh generation, and discretize the flow field of the computational domain using the finite volume method.

[0028] Step 3: Set the boundary conditions of the computational fluid dynamics model.

[0029] For example, the set boundary conditions may include the following: inlet boundary conditions (specifying the velocity distribution at the inlet, given the static pressure and total pressure at the inlet, and prescribing the mass flow rate at the inlet); outlet boundary conditions (setting the static pressure at the outlet, applicable to the case where the flow is fully developed at the outlet, and prescribing the mass flow rate at the outlet); wall boundary conditions (the fluid velocity at the wall is zero, the fluid velocity at the wall is not zero, applicable to ideal fluids, and specifying the wall temperature or heat flux); symmetric boundary conditions, periodic boundary conditions, far-field boundary conditions, initial conditions, etc.

[0030] It should be noted that when setting the inlet wind speed in the inlet boundary conditions, the following operating steps can be adopted:

[0031] Based on the measured wind speed data of the meteorological station at the bridge site, combined with Figure 3 the exponential inlet wind profile characteristics shown, the inlet wind speed at a specified vertical distance from the lowest point of the air inlet is calculated using the inlet wind speed calculation model. Among them, the expression of the inlet wind speed calculation model is: In Equation (1), U h represents the inlet wind speed, U b represents the wind speed at the elevation position of the observation station, z h represents the height of the air inlet location, z b represents the vertical distance from the observation station to the lowest point of the air inlet, and α represents the ground roughness coefficient. According to Equation (1), the inlet wind speed U h at a vertical distance of z h from the lowest point of the inlet can be calculated.

[0032] Step 4: Perform computational fluid dynamics analysis using the set boundary conditions to obtain the first wind speed distribution simulation result.

[0033] Step 5: Obtain the average wind speed in the bridge site canyon area according to the first wind speed distribution simulation result.

[0034] The average wind speed in the bridge site canyon area can be calculated using the steady-state solver simpleFoam in the computational fluid dynamics software OpenFOAM.

[0035] Step 6: Obtain the canyon wind speed correction coefficient and the structural surface wind speed correction coefficient.

[0036] 1. Obtain the canyon wind speed correction coefficient, including the following steps:

[0037] Step 6.1.1: Use the first wind speed distribution simulation result to perform equally spaced sampling on the wind speed data within the elevation range from the arch foot to the arch top to obtain a wind speed observation sample. The wind speed observation sample contains sampling information at multiple sampling points, and the sampling information includes the wind direction and wind speed.

[0038] Step 6.1.2: Use the first correction model to correct the wind speed observation sample to obtain a canyon wind speed correction coefficient observation sample.

[0039] The canyon wind speed correction coefficient observation sample contains canyon wind speed correction coefficient observation data at multiple observation points within the canyon cross-section. Among them, the observation points correspond one-to-one with the sampling points. Specifically, the expression of the first correction model is: In Equation (2), k 1 represents the canyon wind speed correction coefficient observation data, b represents the lateral distance between the midpoint of the main beam and the observation point within the canyon cross-section, h represents the vertical distance between the lowest point of the entrance and the observation point within the canyon cross-section, and U v (b, h) represents the wind speed at the observation point within the canyon cross-section.

[0040] Step 6.1.3: Based on the multiple polynomial regression method, use the canyon wind speed correction coefficient observation sample and the coordinate data set for least squares fitting to obtain the canyon wind speed correction coefficient model at different positions of the canyon cross-section where the bridge site is located.

[0041] Among them, the coordinate data set contains the coordinate data of multiple observation points. Further, the expression of the canyon wind speed correction coefficient model is: p + q ≤ 3 (3); in Equation (3), is the fitting value representing the canyon wind speed correction coefficient, p represents the fitting order of parameter b, q represents the fitting order of parameter h, and ω pq is the joint term fitting parameter representing parameters b and h.

[0042] Step 6.1.4: Calculate the canyon wind speed correction coefficient by using the canyon wind speed correction coefficient model.

[0043] 2. Obtain the structural surface wind speed correction coefficient, including the following steps:

[0044] Step 6.2.1: Conduct two-dimensional numerical simulation of the average wind speed according to the shape of the cross-section of the stiffening frame arch rib and the average wind speed to obtain the second wind speed distribution simulation result at the cross-section of the stiffening frame arch rib.

[0045] Step 6.2.2: Obtain the near-wall wind speed value of the cross-section of the stiffening frame arch rib according to the second wind speed distribution simulation result.

[0046] Among them, the near-wall wind speed value includes: the first near-wall surface wind speed value, the second near-wall surface wind speed value, and the third near-wall surface wind speed value. Further, the first near-wall surface wind speed value is the near-wall wind speed value of the windward surface, the second near-wall surface wind speed value is the near-wall wind speed value of the side wind surface, and the third near-wall surface wind speed value is the near-wall wind speed value of the leeward surface. The positions of the windward surface, the side wind surface, and the leeward surface in the main arch ring cross-section structure are as Figure 4 shown.

[0047] Step 6.2.3: Use the second correction model to correct the near-wall wind speed value of the cross-section of the stiffening frame arch rib to obtain the structural surface wind speed correction coefficient.

[0048] The expression of the second correction model is: In formula (4), k 2 is the structural surface wind speed correction coefficient, U s represents the near-wall wind speed value, U s includes the near-wall wind speed values of the windward surface, the side wind surface, and the leeward surface, and U si is the inlet wind speed of the calculation domain.

[0049] Step 7: Obtain the measured wind speed at the bridge site observation station, and obtain the wind speed on the surface of the arch rib according to the canyon wind speed correction coefficient, the structural surface wind speed correction coefficient, and the measured wind speed at the bridge site observation station.

[0050] Specifically, use the arch rib structural surface wind speed calculation model, the canyon wind speed correction coefficient, the structural surface wind speed correction coefficient, and the measured wind speed at the bridge site observation station to calculate the wind speed on the surface of the arch rib. Among them, the expression of the arch rib structural surface wind speed calculation model is: In formula (5), U 0 represents the measured wind speed at the bridge site observation station.

[0051] Step 8: Obtain the convective heat transfer coefficient of the arch rib structure at the bridge site according to the wind speed on the surface of the arch rib.

[0052] including the following steps:

[0053] Step 8.1: Collect the temperature difference between the ambient temperature and the bridge surface temperature.

[0054] Step 8.2: Calculate the convective heat transfer coefficient by using the convective heat transfer coefficient calculation model, the temperature difference, and the surface wind speed of the arch rib structure.

[0055] Among them, the expression of the convective heat transfer coefficient calculation model is: In Equation (6), h c represents the convective heat transfer coefficient, and ΔT represents the temperature difference between the ambient temperature and the bridge surface temperature.

[0056] Step 9: Obtain the geographical angles required for solar radiation.

[0057] Regarding the structural geographical angle parameters, combined with Figure 5 Calculate the geographical angles required for solar radiation through the following formulas:

[0058]

[0059] sinβ = coslcoshcosδ + sinlsinδ (8);

[0060]

[0061] In Equations (7) to (9), δ represents the solar declination angle, N represents the date serial number in a year, β represents the solar altitude angle, l represents the geographical latitude, μ represents the solar hour angle, represents the solar azimuth angle, and σ represents the angle of direct sunlight.

[0062] Step 10: Obtain the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the arch rib structure surface according to the geographical angles.

[0063] The calculation expression of the cosine value is:

[0064] In Equation (10), d y = sinβ, d x , d y and d z together represent the reverse vector of direct sunlight (d x , d y , d z ), fx represents the component of the normal vector in the x-axis direction, fy represents the component of the normal vector in the y-axis direction, f z represents the component of the normal vector in the z-axis direction, f x , f y and f zCollectively represent the unit normal vector of the surface of the arch rib structure (f x , f y , f z ).

[0065] Step 11: Analyze the direct solar radiation on the surface of the arch rib structure based on the cosine value to obtain the area of the arch rib structure affected by direct solar radiation.

[0066] Specifically, it includes the following steps:

[0067] Step 11.1: If cosθ ≤ 0, output "The surface of the arch rib structure is not affected by direct solar radiation"; if cosθ > 0, proceed to Step 11.2 for mutual occlusion judgment.

[0068] If cosθ > 0, it indicates that the surface is affected by direct solar radiation under the condition that there is no occlusion by other surfaces at this time, and further mutual occlusion judgment is required; conversely, if cosθ ≤ 0, it means that the surface is not affected by direct solar radiation at this time, and no mutual occlusion judgment is needed. The method principle of mutual occlusion judgment refers to Figure 6 .

[0069] Step 11.2: Mark all the surfaces that externally occlude other surfaces on the arch rib structure surface as the first surface, and mark all the surfaces that are externally occluded on the arch rib structure surface as the second surface.

[0070] In the mutual occlusion judgment, mark the surfaces that may occlude other surfaces outside the arch rib structure as the first surface s 1 , and classify the first surface into the set S z ; mark the surfaces that may be occluded externally as the second surface s 2 , and classify the second surface into the set S d .

[0071] Step 11.3: Execute Step 11.3.1 for each second surface to complete the mutual occlusion judgment and obtain all the points affected by direct solar radiation.

[0072] Step 11.3.1: For each point in the second surface, judge whether the ray formed by the coordinates of the point and the reverse vector of direct sunlight intersects with the plane where the first surface is located. The specific implementation steps are as follows:

[0073] Let the plane equation of the first surface be Ax + By + Cz + D = 0 (11), and a certain point O s2 in the second surface has coordinates (x 0 , y 0 , z 0 ), and a certain point O s2 in the plane has coordinates and the reverse vector of direct sunlight (d x , d y , d z)The ray equation formed is: (12). In equation (12), t is a variable used to determine any point of the light ray in space.

[0074] Based on the above plane equation and ray equation, the execution steps for determining whether the ray intersects the first surface are as follows:

[0075] S1: Extract the intersection point of the ray formed by the point and the reverse vector of direct sunlight with the first surface.

[0076] The specific method is: Substitute the ray equation into the plane equation of the first surface, and we can get: (13). If Ad x + Bd y + Cd z = 0, it means the ray is parallel to the plane, and this point can be directly irradiated by the sun at this time; if Ad x + Bd y + Cd z ≠ 0 and t ≤ 0, it means the ray does not intersect the plane, and this point can be directly irradiated by the sun at this time; if Ad x + Bd y + Cd z ≠ 0 and t > 0, it means the ray intersects the plane, and it is necessary to further determine whether the intersection point of the ray and the plane is within the boundary range of the first surface.

[0077] S2: Use the cross product operation of vectors to determine whether the intersection point falls within the corresponding first surface; if it falls within the first surface, add a first mark to the first surface; if it does not fall within the first surface, add a second mark to the first surface.

[0078] Let the corner points of the first surface of the convex polygon be arranged in clockwise order as {P 1 , P 2 , …, P i , … P n}, the intersection point of the ray and the plane where the first surface is located is O 1 , and the space vector between the point O 1 and the corner point P i is The cross product expression of adjacent vectors is:

[0079] If for any i = 1, 2, … n, there is a dot product it means the point O 1 is inside the first surface, and the point O s2 inside the second surface is blocked by the first surface at this time and is not directly irradiated by the sun; conversely, if there exists it means the point O 1 is outside the first surface, and the point O s2It is not blocked by the first surface at this time.

[0080] S3: Determine whether each first surface has a first mark; if it has a first mark, it is determined that the points within the second surface are blocked; if it does not have a first mark, it is determined that the points within the second surface are not blocked, and the unblocked points are output.

[0081] Step 12: Obtain the direct radiation intensity, scattered radiation intensity, and reflected radiation intensity within the area affected by direct solar radiation.

[0082] Step 13: Obtain the solar radiation heat flux density within the area affected by direct solar radiation based on the direct radiation intensity, scattered radiation intensity, and reflected radiation intensity.

[0083] The calculation model expression for the direct radiation intensity is: I dh = I dh0 cosθ(16);

[0084] The calculation model expression for the scattered radiation intensity is:

[0085] The calculation model expression for the reflected radiation intensity is:

[0086] The calculation model expression for the solar radiation heat flux density is: q s = αI = α(I dh + I sh + I gr )(19);

[0087] In equations (16) to (19), I dh represents the direct radiation intensity on the surface of the arch rib structure, I dh0 represents the direct solar radiation on the horizontal plane of the ground surface, I sh represents the scattered radiation intensity on the surface of the arch rib structure, I sh0 represents the atmospheric scattered radiation on the horizontal plane of the ground surface, I gr represents the reflected radiation intensity on the surface of the arch rib structure, K e represents the surface radiation reflectivity, γ represents the angle between the tangential direction of the structural surface and the horizontal plane, q s represents the solar radiation heat flux density received on the surface of the arch rib structure under sunlight conditions, α represents the short-wave absorptivity of the surface of the arch rib structure to solar radiation, and I represents the total solar radiation intensity on the surface of the arch rib structure;

[0088] In equation (20), K t represents the clear sky index, K d represents the scattering rate, I G represents the average solar radiation above the atmosphere, I 0Represents the sum of all sky solar radiation on the ground surface horizontal plane.

[0089] Step 14: Based on the convective heat transfer coefficient and solar radiation flux density, perform temperature field simulation on the temperature field of the long-span stiffening steel truss arch rib to obtain the temperature distribution of the arch rib.

[0090] It includes the following steps:

[0091] Step 14.1: Set the thermal parameters of the material in the ABAQUS finite element analysis software, establish a numerical model of the temperature field of the long-span stiffening steel truss arch bridge, and input the measured data such as the ambient temperature and solar radiation value related to the thermal boundary conditions. The thermal boundary conditions are as Figure 7 shown.

[0092] Step 14.2: Extract the spatial position coordinate information and the external normal direction information of the model elements through a python script, realize the real-time update of various input information during the transient heat transfer process of ABAQUS through the UEXTERNALDB subroutine, and use the DFLUX and FILM subroutines to refine the shadow occlusion area and the convective heat transfer distribution, and then solve the temperature field of the arch rib structure.

[0093] In summary, a method for analyzing the temperature field of a long-span stiffening steel truss arch rib proposed in the first aspect of this embodiment fully combines the measured environmental data in the bridge site area, considers the influence of the solar radiation shadow occlusion effect, and uses the numerical simulation method to realize the simulation of the temperature field of the ultra-long-span stiffening steel truss arch rib, which can effectively solve the problem that it is difficult to accurately describe the temperature field distribution characteristics of the proposed railway arch bridge in alpine and canyon areas. This method first corrects the convective heat transfer coefficient of the structure based on the measured ambient temperature, wind speed and spatial position information; then combines the solar radiation related parameters obtained by satellite inversion, and corrects the total solar radiation intensity on the surface of the structure through the shadow occlusion algorithm; on this basis, a refined finite element model of the temperature field of the ultra-long-span stiffening steel truss arch bridge under the combined influence of various environmental factors is established. The present invention considers the uneven distribution of the convective heat transfer coefficient and the solar radiation shadow occlusion effect, and establishes a finite element model of the temperature field of the long-span stiffening steel truss arch rib that reflects the real-time update and refined distribution of the thermal boundary conditions, and can truly reflect the temperature distribution law of the arch rib structure.

[0094] Corresponding to the method proposed in the first aspect above, a temperature field analysis system for a long-span stiffening steel truss arch rib is proposed in the second aspect of this embodiment, including:

[0095] A correction coefficient acquisition module, used to acquire the canyon wind speed correction coefficient and the structural surface wind speed correction coefficient;

[0096] A measured data acquisition module, used to acquire the measured wind speed of the bridge site observation station;

[0097] The wind field numerical simulation module is used to obtain the wind speed on the surface of the arch rib structure according to the canyon wind speed correction coefficient, the surface wind speed correction coefficient of the structure, and the measured wind speed at the bridge site observation station;

[0098] The heat transfer coefficient acquisition module is used to obtain the convective heat transfer coefficient of the arch rib structure at the bridge site according to the wind speed on the surface of the arch rib structure;

[0099] The geographical angle acquisition module is used to obtain the geographical angles required for solar radiation;

[0100] The trigonometric function calculation module is used to obtain the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographical angles;

[0101] The direct solar radiation analysis module is used to analyze the direct solar radiation effect on the surface of the arch rib structure according to the cosine value, and obtain the area of the arch rib structure affected by direct solar radiation;

[0102] The radiation intensity acquisition module is used to obtain the direct radiation intensity, scattered radiation intensity, and reflected radiation intensity within the area affected by direct solar radiation;

[0103] The heat flux density acquisition module is used to obtain the solar radiation heat flux density within the area affected by direct solar radiation according to the direct radiation intensity, the scattered radiation intensity, and the reflected radiation intensity;

[0104] The temperature field simulation module is used to perform temperature field simulation on the temperature field of the long-span stiffening skeleton arch rib based on the convective heat transfer coefficient and the solar radiation flux density, and obtain the arch rib temperature distribution.

[0105] Furthermore, the system further includes:

[0106] The inlet wind speed acquisition module is used to obtain the inlet wind speed at a specified vertical distance from the lowest point of the air inlet according to the inlet wind speed calculation model; the expression of the inlet wind speed calculation model is: In Equation (1), U h represents the inlet wind speed, U b represents the wind speed at the elevation position of the observation station, z h represents the height of the location where the air inlet is located, z b represents the vertical distance from the observation station to the lowest point of the air inlet, and α represents the ground roughness coefficient;

[0107] The boundary condition setting module is used to set the boundary conditions of the computational fluid dynamics model according to the inlet wind speed;

[0108] The dynamics analysis module is used to perform computational fluid dynamics analysis using the set boundary conditions to obtain the first wind speed distribution simulation result;

[0109] An average wind speed acquisition module, configured to obtain the average wind speed of the bridge site canyon area according to the first wind speed distribution simulation result.

[0110] Further, the correction coefficient acquisition module includes:

[0111] A wind speed data sampling unit, configured to equally space sample the wind speed data within the elevation range from the arch springing to the arch crown by using the first wind speed distribution simulation result, so as to obtain a wind speed observation sample; the wind speed observation sample contains sampling information of multiple sampling points; the sampling information includes the wind direction and the wind speed;

[0112] A first sample correction unit, configured to correct the wind speed observation sample by using a first correction model to obtain a canyon wind speed correction coefficient observation sample; the canyon wind speed correction coefficient observation sample contains canyon wind speed correction coefficient observation data of multiple observation points within the canyon cross-section, and the observation points correspond to the sampling points one by one; the expression of the first correction model is: In formula (2), k 1 represents the canyon wind speed correction coefficient observation data, b represents the lateral distance between the midpoint of the main girder and the observation point within the canyon cross-section, h represents the vertical distance between the lowest point of the entrance and the observation point within the canyon cross-section, U v (b, h) represents the wind speed of the observation point within the canyon cross-section;

[0113] A least squares fitting unit, configured to perform least squares fitting on the canyon wind speed correction coefficient observation sample and a coordinate data set to obtain a canyon wind speed correction coefficient model; the coordinate data set contains coordinate data of multiple observation points, and the expression of the canyon wind speed correction coefficient model is: In formula (3), is the fitting value representing the canyon wind speed correction coefficient, p represents the fitting order of parameter b, q represents the fitting order of parameter h, ω pq is the joint term fitting parameter representing parameter b and parameter h;

[0114] A correction coefficient calculation unit, configured to calculate the canyon wind speed correction coefficient by using the canyon wind speed correction coefficient model;

[0115] A wind speed numerical simulation unit, configured to perform two-dimensional average wind speed numerical simulation according to the shape of the cross-section of the stiffening frame arch rib and the average wind speed to obtain a second wind speed distribution simulation result at the cross-section of the stiffening frame arch rib;

[0116] The near-wall wind speed acquisition unit is used to obtain the near-wall wind speed values of the cross-section of the stiffening skeleton arch rib according to the second wind speed distribution simulation result; the near-wall wind speed values include: the first near-wall surface wind speed value, the second near-wall surface wind speed value, and the third near-wall surface wind speed value; the first near-wall surface wind speed value is the near-wall wind speed value of the windward surface, the second near-wall surface wind speed value is the near-wall wind speed value of the side wind surface, and the third near-wall surface wind speed value is the near-wall wind speed value of the leeward surface;

[0117] The near-wall wind speed correction unit is used to correct the near-wall wind speed values of the cross-section of the stiffening skeleton arch rib by using the second correction model to obtain the structural surface wind speed correction coefficient; the expression of the second correction model is: In formula (4), k 2 Structural surface wind speed correction coefficient, U s Represents the near-wall wind speed value, U s Includes the near-wall wind speed values of the windward surface, the side wind surface, and the leeward surface, U si Represents the inlet wind speed of the computational domain.

[0118] Furthermore, the wind field data simulation module includes: a wind speed data calculation unit, which is used to calculate the wind speed on the surface of the arch rib by using the wind speed calculation model on the surface of the arch rib structure, the canyon wind speed correction coefficient, the structural surface wind speed correction coefficient, and the measured wind speed at the bridge site observation station; the expression of the wind speed calculation model on the surface of the arch rib structure is: In formula (5), U 0 Represents the measured wind speed at the bridge site observation station.

[0119] Furthermore, the heat transfer coefficient acquisition module includes:

[0120] A temperature difference data acquisition unit, which is used to collect the temperature difference between the ambient temperature and the surface temperature of the bridge;

[0121] A heat transfer coefficient calculation unit, which is used to calculate the convective heat transfer coefficient by using the convective heat transfer coefficient calculation model, the temperature difference, and the wind speed on the surface of the arch rib structure; the expression of the convective heat transfer coefficient calculation model is: In formula (6), h c Represents the convective heat transfer coefficient, and ΔT represents the temperature difference between the ambient temperature and the surface temperature of the bridge.

[0122] Furthermore, the geographical angle acquisition module includes:

[0123] A first model retrieval unit, which is used to retrieve the calculation expression of the geographical angle; the calculation expression of the geographical angle includes:

[0124]

[0125] sinβ = coslcoshcosδ + sinlsinδ (8);

[0126]

[0127] In formulas (7) to (9), δ represents the solar declination angle, N represents the serial number of the date in a year, β represents the solar altitude angle, l represents the geographical latitude, μ represents the solar hour angle, represents the solar azimuth angle, and σ represents the angle of direct sunlight;

[0128] The calculation expression of the cosine value is:

[0129] A geographical angle calculation unit for calculating the geographical angles required for solar radiation according to the calculation expression of the geographical angles.

[0130] Furthermore, the direct sunlight analysis model includes:

[0131] A numerical analysis unit for performing numerical analysis on the cosine value; if the cosine value ≤ 0, output "the surface of the arch rib structure is not directly irradiated by the sun"; if the cosine value > 0, drive the object marking unit to work;

[0132] A first marking unit for marking all the surfaces that block other surfaces outside the arch rib structure surface as the first surface, and marking all the surfaces blocked outside the arch rib structure surface as the second surface;

[0133] A first control unit for traversing each second surface, and driving the second control unit to work each time a second surface is accessed, and outputting all the points directly irradiated by the sun;

[0134] A second control unit for traversing each point within the second surface, and driving the intersection point extraction unit to work each time a point is accessed;

[0135] An intersection point extraction unit for extracting the intersection points of the ray formed by the point and the reverse vector of the direct sunlight with the first surface;

[0136] A cross product operation unit for determining whether the intersection point falls within the corresponding first surface by using the cross product operation of vectors;

[0137] A second marking unit for adding a first mark to the first surface when the intersection point falls within the first surface; and adding a second mark to the first surface when the intersection point does not fall within the first surface;

[0138] An occlusion determination unit for determining whether each of the first surfaces has the first mark; if it has the first mark, it is determined that the point in the second surface is occluded; if it does not have the first mark, it is determined that the point in the second surface is not occluded, and the unoccluded points are output.

[0139] Further, the radiation intensity acquisition module includes:

[0140] A second model retrieval unit for retrieving the calculation model of the direct radiation intensity, the calculation model of the scattered radiation intensity, and the calculation model of the reflected radiation intensity;

[0141] A radiation intensity calculation unit for calculating the direct radiation intensity in the area affected by direct solar radiation according to the calculation model of the direct radiation intensity, calculating the direct radiation intensity, scattered radiation intensity, and reflected radiation intensity in the area affected by direct solar radiation according to the calculation model of the scattered radiation intensity, and calculating the reflected radiation intensity in the area affected by direct solar radiation according to the calculation model of the reflected radiation intensity;

[0142] The expression of the calculation model of the direct radiation intensity is: I dh = I dh0 cosθ(11);

[0143] The expression of the calculation model of the scattered radiation intensity is:

[0144] The expression of the calculation model of the reflected radiation intensity is:

[0145] The expression of the calculation model of the solar radiation heat flux density is: q s = αI = α(I dh + I sh + I gr )(14);

[0146] In equations (11) to (14), I dh represents the direct radiation intensity on the surface of the arch rib structure, I dh0 represents the direct solar radiation on the horizontal surface of the ground, Ish represents the scattered radiation intensity on the surface of the arch rib structure, I sh0 represents the atmospheric scattered radiation on the horizontal surface of the ground, I gr represents the reflected radiation intensity on the surface of the arch rib structure, K e represents the surface radiation reflectivity, γ represents the angle between the tangential direction of the structure surface and the horizontal plane, q s represents the solar radiation heat flux density received on the surface of the arch rib structure under sunlight conditions, α represents the short-wave absorption rate of the surface of the arch rib structure to solar radiation, and I represents the total solar radiation intensity on the surface of the arch rib structure;

[0147] In Equation (15), K t represents the clear sky index, and K d represents the scattering rate, and I G is the average value of solar radiation at the top of the atmosphere, and I 0 represents the sum of all sky sunshine radiation on the ground horizontal plane.

[0148] Based on the method provided in the first aspect and the system provided in the second aspect above, in the third aspect of this embodiment, a computer device for executing the method described in the first aspect or any method that may be involved in the method described in the first aspect is provided, including a memory, a processor, and a transceiver that are communicatively connected in sequence. Among them, the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the method described in the first aspect or any method that may be involved in the method described in the first aspect. Specifically, for example, the memory may include, but is not limited to, random access memory (RAM), read-only memory (ROM), flash memory, first input first output (FIFO), and / or first input last output (FILO), etc.; the processor may be, but is not limited to, a microprocessor of the STM32F105 series. In addition, the computer device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0149] For the working process, working details, and technical effects of the computer device provided in the third aspect of this embodiment, reference may be made to the method described in the first aspect or any method that may be involved in the method described in the first aspect, and details will not be elaborated here.

[0150] In the fourth aspect of this embodiment, a computer-readable storage medium storing the method described in the first aspect or any method that may be involved in the method described in the first aspect is provided, that is, instructions are stored on the computer-readable storage medium, and when the instructions run on a computer, the method described in the first aspect or any method that may be involved in the method described in the first aspect is executed. Among them, the computer-readable storage medium refers to a carrier for storing data, and may include, but is not limited to, floppy disks, optical discs, hard disks, flash memories, USB flash drives, and / or memory sticks, etc. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0151] For the working process, working details and technical effects of the foregoing computer-readable storage medium provided in the fourth aspect of this embodiment, reference may be made to the method described in the first aspect or any method that may be related to the method described in the first aspect, and details are not elaborated herein.

[0152] In the fifth aspect of this embodiment, a computer program product including instructions is provided. When the instructions run on a computer, the computer is caused to execute the method described in the first aspect or any method that may be related to the method described in the first aspect. Among them, the computer may be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices.

[0153] It should be understood that the "system", "device", "unit" and / or "module" used in this specification are a way to distinguish different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the said words can be replaced by other expressions.

[0154] As shown in this specification and the claims, unless the context clearly indicates an exception, words such as "a", "an", "one" and / or "the" are not specifically singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0155] The specific embodiments described above further elaborate on the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0156] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the limited conditions under which the present invention can be implemented. Therefore, they do not have technical substance significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and the like cited in this specification are only for the convenience of clear narration and are not used to limit the scope that the present invention can be implemented. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope that the present invention can be implemented.

Claims

1. A temperature field analysis method for a large-span rigid skeleton arch rib, characterized in that: The following steps are involved: Obtain canyon wind speed correction factor and structure surface wind speed correction factor; Obtain the measured wind speed at the bridge site observation station; Obtaining the surface wind speed of the arch rib structure according to the canyon wind speed correction coefficient, the structure surface wind speed correction coefficient and the measured wind speed at the bridge site observation station; Obtaining the convective heat transfer coefficient of the arch rib structure at the bridge site according to the surface wind speed of the arch rib structure; Obtaining the geographical angle required for solar radiation; obtaining the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographical angle; Analyze the direct sunlight effect on the surface of the arch rib structure according to the cosine value to obtain the area of ​​the arch rib structure affected by direct sunlight; Obtaining the direct radiation intensity, scattered radiation intensity and reflected radiation intensity in the area directly affected by the sun; obtaining the solar radiation heat flux density in the area directly affected by the sun according to the direct radiation intensity, the scattered radiation intensity and the reflected radiation intensity; Based on the convective heat transfer coefficient and the solar radiation flux density, a temperature field simulation is performed on the temperature field of the large-span rigid skeleton arch rib to obtain the arch rib temperature distribution.

2. The method for analyzing temperature field of a large-span rigid skeleton arch rib according to claim 1, characterized in that: Before obtaining the canyon wind speed correction coefficient and the structure surface wind speed correction coefficient, the following steps are also included: The inlet wind speed calculation model is used to obtain the inlet wind speed at a specified vertical distance from the lowest point of the air inlet. The expression of the inlet wind speed calculation model is: In formula (1), U h Indicates the inlet wind speed, U b represents the wind speed at the observation station elevation, z h Indicates the height of the air inlet, z b represents the vertical distance between the observation station and the lowest point of the air inlet, and α represents the ground roughness coefficient; setting boundary conditions of a computational fluid dynamics model according to the inlet wind speed; The set boundary conditions are used to perform computational fluid dynamics analysis to obtain a first wind speed distribution simulation result; The average wind speed in the canyon area at the bridge site is obtained based on the first wind speed distribution simulation result.

3. The method for analyzing temperature field of a large-span rigid skeleton arch rib according to claim 2, characterized in that: Obtaining the canyon wind speed correction factor includes the following steps: Using the first wind speed distribution simulation result, equally spaced sampling is performed on wind speed data within the range from the arch foot to the arch top elevation to obtain wind speed observation samples; the wind speed observation samples contain sampling information of multiple sampling points; the sampling information contains wind direction and wind speed; The wind speed observation samples are corrected using the first correction model to obtain canyon wind speed correction coefficient observation samples; the canyon wind speed correction coefficient observation samples include canyon wind speed correction coefficient observation data of multiple observation points in the canyon section, and the observation points correspond to the sampling points one by one; the expression of the first correction model is: In formula (2), k1 represents the observation data of the canyon wind speed correction coefficient, b represents the horizontal distance between the middle point of the main beam and the observation point in the canyon section, h represents the vertical distance between the lowest point of the entrance and the observation point in the canyon section, and U v (b,h) represent the wind speed at the observation point in the canyon section; The canyon wind speed correction coefficient model is obtained by performing least square fitting on the canyon wind speed correction coefficient observation sample and the coordinate data set; the coordinate data set contains the coordinate data of multiple observation points, and the expression of the canyon wind speed correction coefficient model is: In formula (3), is the fitting value of the canyon wind speed correction coefficient, p is the fitting order of parameter b, q is the fitting order of parameter h, ω pq is the joint fitting parameter representing parameter b and parameter h; The canyon wind speed correction coefficient is calculated using the canyon wind speed correction coefficient model.

4. The method for analyzing temperature field of a large-span rigid skeleton arch rib according to claim 3 is characterized in that: Obtaining the wind speed correction factor on the structure surface includes the following steps: Performing a two-dimensional average wind speed numerical simulation according to the shape of the cross section of the rigid skeleton arch rib and the average wind speed, and obtaining a second wind speed distribution simulation result at the cross section of the rigid skeleton arch rib; Obtain the near-wall wind speed value of the cross section of the rigid skeleton arch rib according to the second wind speed distribution simulation result; the near-wall wind speed value includes: a first near-wall wind speed value, a second near-wall wind speed value and a third near-wall wind speed value; the first near-wall wind speed value is the near-wall wind speed value of the windward side, the second near-wall wind speed value is the near-wall wind speed value of the lateral side, and the third near-wall wind speed value is the near-wall wind speed value of the leeward side; The near-wall wind speed value of the cross section of the rigid skeleton arch rib is corrected by using the second correction model to obtain the wind speed correction coefficient of the structure surface; the expression of the second correction model is: In formula (4), k2 is the wind speed correction coefficient on the structure surface, U s To represent the wind speed near the wall, U s Including the wind speed near the wall on the windward side, the wind speed near the wall on the sidewind side, and the wind speed near the wall on the leeward side, U si is the inlet wind speed of the computational domain.

5. A temperature field analysis method for a large-span rigid skeleton arch rib according to claim 4, characterized in that: The method for obtaining the surface wind speed of the arch rib structure is: using the surface wind speed calculation model of the arch rib structure, the canyon wind speed correction coefficient, the structure surface wind speed correction coefficient and the measured wind speed of the bridge site observation station to calculate the surface wind speed of the arch rib structure; The expression of the wind speed calculation model on the arch rib structure surface is: In formula (5), U0 represents the wind speed measured at the bridge site observation station.

6. A temperature field analysis method for a large-span rigid skeleton arch rib according to claim 5, characterized in that: Obtaining the convective heat transfer coefficient of the arch rib structure at the bridge site includes the following steps: Collect the temperature difference between the ambient temperature and the bridge surface temperature; The convective heat transfer coefficient is calculated using the convective heat transfer coefficient calculation model, the temperature difference and the wind speed on the surface of the arch rib structure; the expression of the convective heat transfer coefficient calculation model is: In formula (6), h c represents the convective heat transfer coefficient, and ΔT represents the temperature difference between the ambient temperature and the bridge surface temperature.

7. A temperature field analysis method for a large-span rigid skeleton arch rib according to any one of claims 1 to 6, characterized in that: The calculation expression of the geographical angle includes: In equations (7) to (9), δ represents the solar declination angle, N represents the date number in a year, β represents the solar altitude angle, l represents the geographic latitude, and μ represents the solar hour angle. represents the solar azimuth, σ represents the angle of direct sunlight; The calculation expression of the cosine value is: In formula (10), d y = sinβ, d x ,d y and d z Together they represent the reverse direction of direct sunlight (d x ,d y ,d z ), fx represents the component of the normal vector in the x-axis direction, fy represents the component of the normal vector in the y-axis direction, and f z represents the component of the normal vector in the z-axis direction, f x 、f y and f z Together they represent the normal unit vector of the arch rib structure surface (f x ,f y ,f z ).

8. A temperature field analysis method for a large-span rigid skeleton arch rib according to claim 7, characterized in that: The analysis of direct solar radiation on the surface of the arch rib structure includes the following steps: S1: If cosθ≤0, output "the surface of the arch rib structure is not affected by direct sunlight"; if cosθ>0, execute S2; S2: mark all surfaces outside the arch rib structure surface that block other surfaces as first surfaces, and mark all surfaces outside the arch rib structure surface that are blocked as second surfaces; S3: executing S31 for each of the second surfaces to obtain all points directly exposed to sunlight; S31: For each point in the second surface, execute S31.1 to S31.3; S31.1: extracting the intersection of the ray formed by the point and the reverse vector of the direct sunlight and the first surface; S31.2: using a vector cross product operation to determine whether the intersection point falls within the corresponding first surface; if it falls within the first surface, adding a first mark to the first surface; if it does not fall within the first surface, adding a second mark to the first surface; S31.3: Determine whether each of the first surfaces has the first mark; if it has the first mark, determine that the point in the second surface is blocked; if it does not have the first mark, determine that the point in the second surface is not blocked, and output the unblocked point.

9. A temperature field analysis method for a large-span rigid skeleton arch rib according to claim 7, characterized in that: The calculation model expression of the direct radiation intensity is: dh =I dh0 cosθ(11); The calculation model expression of the scattered radiation intensity is: The calculation model expression of the reflected radiation intensity is: The calculation model expression of the solar radiation heat flux density is: s =αI=α(I dh +I sh +I gr )(14); In formula (11) to formula (14), I dh Represents the direct radiation intensity of the arch rib structure surface, I dh0 Represents the direct solar radiation on the horizontal surface of the earth, I sh represents the scattered radiation intensity on the surface of the arch rib structure, I sh0 represents the atmospheric scattered radiation at the surface level, I gr represents the reflected radiation intensity of the arch rib structure surface, K e represents the surface radiation reflectivity, γ represents the angle between the tangent direction of the structure surface and the horizontal plane, q s It represents the solar radiation heat flux density received by the arch rib structure surface under sunshine conditions, α represents the short-wave absorption rate of the arch rib structure surface to solar radiation, and I represents the total solar radiation intensity on the arch rib structure surface; In formula (15), K t represents the clear sky index, K d represents the scattering rate, I G To represent the average solar radiation at the upper boundary of the atmosphere, I0 represents the sum of all sky solar radiation at the horizontal surface of the earth.

10. A temperature field analysis system for large-span rigid skeleton arch ribs, characterized in that: include: A correction coefficient acquisition module is used to obtain a canyon wind speed correction coefficient and a structure surface wind speed correction coefficient; The measured data acquisition module is used to obtain the measured wind speed at the bridge site observation station; A wind field numerical simulation module, used for obtaining the surface wind speed of the arch rib structure according to the canyon wind speed correction coefficient, the structure surface wind speed correction coefficient and the measured wind speed of the bridge site observation station; A heat transfer coefficient acquisition module, used to acquire the convective heat transfer coefficient of the arch rib structure at the bridge site according to the wind speed on the surface of the arch rib structure; A geographic angle acquisition module is used to acquire the geographic angle required for solar radiation; A trigonometric function calculation module, used for obtaining the cosine value of the angle between the reverse direction of direct sunlight and the outer normal of the surface of the arch rib structure according to the geographical angle; A solar direct radiation analysis module is used to analyze the solar direct radiation effect on the surface of the arch rib structure according to the cosine value to obtain the area of ​​the arch rib structure affected by the solar direct radiation; A radiation intensity acquisition module, used to acquire the direct radiation intensity, scattered radiation intensity and reflected radiation intensity in the area directly affected by the sun; A heat flux density acquisition module, used for acquiring the solar radiation heat flux density in the area directly affected by the sun according to the direct radiation intensity, the scattered radiation intensity and the reflected radiation intensity; The temperature field simulation module is used to perform temperature field simulation on the temperature field of the large-span rigid skeleton arch rib based on the convection heat transfer coefficient and the solar radiation flux density to obtain the arch rib temperature distribution.

11. A temperature field analysis system for large-span rigid skeleton arch ribs according to claim 10, characterized in that: Also includes: An inlet wind speed acquisition module is used to obtain the inlet wind speed at a specified vertical distance from the lowest point of the air inlet according to an inlet wind speed calculation model; The expression of the inlet wind speed calculation model is: In formula (1), U h Indicates the inlet wind speed, U b represents the wind speed at the observation station elevation, z h Indicates the height of the air inlet, z b represents the vertical distance between the observation station and the lowest point of the air inlet, and α represents the ground roughness coefficient; A boundary condition setting module, used for setting the boundary conditions of the computational fluid dynamics model according to the inlet wind speed; A dynamic analysis module, used to perform computational fluid dynamics analysis using the set boundary conditions to obtain a first wind speed distribution simulation result; The average wind speed acquisition module is used to obtain the average wind speed in the canyon area of ​​the bridge site according to the first wind speed distribution simulation result.

12. A temperature field analysis system for large-span rigid skeleton arch ribs according to claim 11, characterized in that: The correction coefficient acquisition module includes: A wind speed data sampling unit, configured to perform equally spaced sampling of wind speed data within the range from the arch foot to the arch top elevation using the first wind speed distribution simulation result, to obtain wind speed observation samples; the wind speed observation samples contain sampling information of multiple sampling points; the sampling information contains wind direction and wind speed; The first sample correction unit is used to correct the wind speed observation sample using the first correction model to obtain a canyon wind speed correction coefficient observation sample; the canyon wind speed correction coefficient observation sample includes canyon wind speed correction coefficient observation data of multiple observation points in the canyon section, and the observation points correspond to the sampling points one by one; the expression of the first correction model is: In formula (2), k1 represents the observation data of the canyon wind speed correction coefficient, b represents the horizontal distance between the middle point of the main beam and the observation point in the canyon section, h represents the vertical distance between the lowest point of the entrance and the observation point in the canyon section, and U v (b,h) represent the wind speed at the observation point in the canyon section; The least squares fitting unit is used to perform least squares fitting on the canyon wind speed correction coefficient observation sample and the coordinate data set to obtain a canyon wind speed correction coefficient model; the coordinate data set includes coordinate data of multiple observation points, and the expression of the canyon wind speed correction coefficient model is: In formula (3), is the fitting value of the canyon wind speed correction coefficient, p is the fitting order of parameter b, q is the fitting order of parameter h, ω pq is the joint fitting parameter representing parameter b and parameter h; A correction coefficient calculation unit, used to calculate the canyon wind speed correction coefficient using the canyon wind speed correction coefficient model; The correction coefficient acquisition module also includes: A wind speed numerical simulation unit is used to perform a two-dimensional average wind speed numerical simulation according to the shape of the cross section of the rigid skeleton arch rib and the average wind speed, and obtain a second wind speed distribution simulation result at the cross section of the rigid skeleton arch rib; A near-wall wind speed acquisition unit is used to acquire the near-wall wind speed value of the cross section of the rigid skeleton arch rib according to the second wind speed distribution simulation result; the near-wall wind speed value includes: a first near-wall surface wind speed value, a second near-wall surface wind speed value and a third near-wall surface wind speed value; the first near-wall surface wind speed value is the near-wall wind speed value of the windward surface, the second near-wall surface wind speed value is the near-wall wind speed value of the crosswind surface, and the third near-wall surface wind speed value is the near-wall wind speed value of the leeward surface; The near-wall wind speed correction unit is used to correct the near-wall wind speed value of the cross section of the rigid skeleton arch rib by using the second correction model to obtain the wind speed correction coefficient of the structure surface; the expression of the second correction model is: In formula (4), k2 is the wind speed correction coefficient on the structure surface, U s To represent the wind speed near the wall, U s Including the wind speed near the wall on the windward side, the wind speed near the wall on the sidewind side, and the wind speed near the wall on the leeward side, U si is the inlet wind speed of the computational domain.

13. A temperature field analysis system for large-span rigid skeleton arch ribs according to claim 12, characterized in that: The wind field data simulation module includes: a wind speed data calculation unit, which is used to calculate the surface wind speed of the arch rib structure by using the arch rib structure surface wind speed calculation model, the canyon wind speed correction coefficient, the structure surface wind speed correction coefficient and the measured wind speed of the bridge site observation station; the expression of the arch rib structure surface wind speed calculation model is: In formula (5), U0 represents the wind speed measured at the bridge site observation station; The heat transfer coefficient acquisition module includes: A temperature difference data acquisition unit is used to acquire the temperature difference between the ambient temperature and the bridge surface temperature; The heat transfer coefficient calculation unit is used to calculate the convective heat transfer coefficient by using the convective heat transfer coefficient calculation model, the temperature difference and the wind speed on the surface of the arch rib structure; the expression of the convective heat transfer coefficient calculation model is: In formula (6), h c represents the convective heat transfer coefficient, ΔT represents the temperature difference between the ambient temperature and the bridge surface temperature; The geographic angle acquisition module includes: The first model calling unit is used to call the calculation expression of the geographical angle; the calculation expression of the geographical angle includes: sinβ=coslcoshcosδ+sinlsinδ(8); In equations (7) to (9), δ represents the solar declination angle, N represents the date number in a year, β represents the solar altitude angle, l represents the geographic latitude, and μ represents the solar hour angle. represents the solar azimuth, σ represents the angle of direct sunlight; The calculation expression of the cosine value is: The geographic angle calculation unit is used to calculate the geographic angle required for solar radiation according to the calculation expression of the geographic angle.

14. A temperature field analysis system for large-span rigid skeleton arch ribs according to claim 13, characterized in that: The solar radiation analysis model includes: A numerical analysis unit is used to perform numerical analysis on the cosine value; if the cosine value is ≤0, output "the surface of the arch rib structure is not directly affected by the sun"; if the cosine value is greater than 0, drive the object marking unit to work; A first marking unit is used to mark all surfaces outside the arch rib structure surface that block other surfaces as first surfaces, and mark all surfaces outside the arch rib structure surface that are blocked as second surfaces; A first control unit is used to traverse each second surface, and drive the second control unit to work each time the second surface is visited, and output all points directly affected by the sun; A second control unit is used for traversing each point in the second surface, and driving the intersection point extraction unit to work each time a point is visited; An intersection point extraction unit, used to extract the intersection point of the ray composed of the point and the reverse vector of the direct sunlight and the first surface; A cross product operation unit, used for determining whether the intersection point falls within the corresponding first surface by using a cross product operation of a vector; A second marking unit, configured to add a first mark to the first surface when the intersection point falls within the first surface; and to add a second mark to the first surface when the intersection point does not fall within the first surface; The mutual occlusion determination unit is used to determine whether each of the first surfaces has the first mark; if it has the first mark, it is determined that the point in the second surface is occluded; if it does not have the first mark, it is determined that the point in the second surface is not occluded, and the unoccluded point is output.

15. A temperature field analysis system for large-span rigid skeleton arch ribs according to claim 14, characterized in that: The radiation intensity acquisition module includes: A second model retrieving unit, used to retrieve the calculation model of the direct radiation intensity, the calculation model of the scattered radiation intensity and the calculation model of the reflected radiation intensity; a radiation intensity calculation unit, used to calculate the direct radiation intensity in the area directly affected by the sun according to the calculation model of the direct radiation intensity, calculate the direct radiation intensity, scattered radiation intensity and reflected radiation intensity in the area directly affected by the sun according to the calculation model of the scattered radiation intensity, and calculate and obtain the reflected radiation intensity in the area directly affected by the sun according to the calculation model of the reflected radiation intensity; The calculation model expression of the direct radiation intensity is: dh =I dh0 cosθ(11); The calculation model expression of the scattered radiation intensity is: The calculation model expression of the reflected radiation intensity is: The calculation model expression of the solar radiation heat flux density is: s =αI=α(I dh +I sh +I gr )(14); In formula (11) to formula (14), I dh Represents the direct radiation intensity of the arch rib structure surface, I dh0 Represents the direct solar radiation on the horizontal surface of the earth, I sh represents the scattered radiation intensity on the surface of the arch rib structure, I sh0 represents the atmospheric scattered radiation at the surface level, I gr represents the reflected radiation intensity of the arch rib structure surface, K e represents the surface radiation reflectivity, γ represents the angle between the tangent direction of the structure surface and the horizontal plane, q s It represents the solar radiation heat flux density received by the arch rib structure surface under sunshine conditions, α represents the short-wave absorption rate of the arch rib structure surface to solar radiation, and I represents the total solar radiation intensity on the arch rib structure surface; In formula (15), K t represents the clear sky index, K d represents the scattering rate, I G To represent the average solar radiation at the upper boundary of the atmosphere, I0 represents the sum of all sky solar radiation at the horizontal surface of the earth.

Images