A design method for an asymmetric inclined tower cable-stayed landscape bridge

Abstract

This application relates to the field of landscape bridge design, and specifically discloses a design method for an asymmetric inclined tower cable-stayed landscape bridge. The method includes: a. Simulating and determining component parameters; b. Generating a finite element structural analysis model; c. Conducting structural analysis and calculation; d. Exporting the calculation results of the model family (); e. Exporting the calculation results of the model family (); f. Conducting structural model inspection; g. Optimizing the component cross-section and checking the bearing capacity. This design method improves the disadvantages in the traditional landscape bridge design process, such as difficult bridge shape finding, improper structural force, and waste of redundant materials. By applying this design method, it is possible to significantly reduce the human input in the design process, use digital means to perform rapid and efficient parametric iterative design on the target designed bridge, strive to seek the optimal solution in the design process, reduce the time cost input of designers, improve efficiency, and have good economic and social benefits.

Description

Technical Field

[0001] The present application relates to the field of landscape bridge design, and in particular to a design method for an asymmetric inclined pylon cable-stayed landscape bridge. Background Art

[0002] With the development of the economic society, the purpose of building bridges is no longer limited to meeting traffic needs. Designers have begun to focus on designing landscape bridges that can not only meet the use functions of bridges but also reflect the economic and technological development level of cities. Under the guidance of the aesthetic design principle, landscape bridges are created by integrating art and structure in combination with engineering conditions and regional characteristics. There are various forms of landscape bridges, and arch cable-stayed bridges, inclined column pylon cable-stayed bridges, and inclined pylon cable-stayed landscape bridges are more commonly used in engineering.

[0003] For example, the invention patent with the authorization announcement number CN111041969A and the patent name of a long-span composite arch bridge and its design and construction method based on the bending and compression design theory, its construction method includes the following steps:

[0004] Prefabricate the arch foot section with a convergent composite curve and the arch belly-arch top section with a hollow structure; prefabricate the arch foot support foundation with an A inclination angle in the horizontal direction of the arch foot support surface; fix the two arch foot support foundations and dock the two arch foot sections with the arch foot support foundations respectively;

[0005] Dock the two ends of the arch belly-arch top section with the arch foot section respectively; judge whether the arch bridge is reliable according to the structure coefficients of each structure of the arch bridge. If so, put the arch bridge into use;

[0006] Each structure includes an arch belly-arch top section, an arch foot section, and an arch foot support foundation; the structure coefficient is the ratio of the measured stress value to the solved stress value of each structure section; the measured stress value is the cross-section stress value actually measured on site for the structure; the solved stress value is the stress value obtained by the structure according to the space analysis algorithm.

[0007] Regarding the above related technologies, the inventor believes that in the design process of cable-stayed bridges (arch bridges), an artificial and mechanized method is usually adopted, and processes such as shape finding, scheme design, and detailed design are carried out in sequence. In the operation process, the scheme comparison cannot be carried out through an iterative parametric method, and the design method is inefficient, and usually the optimal scheme cannot be efficiently screened out. Summary of the Invention

[0008] In order to improve the problems of difficult shape finding and structural optimization of inclined pylon cable-stayed landscape bridges, the present application provides a design method for an asymmetric inclined pylon cable-stayed landscape bridge.

[0009] A design method for an asymmetric inclined pylon cable-stayed landscape bridge provided by the present application adopts the following technical solutions:

[0010] A design method for an asymmetric inclined - tower cable - stayed landscape bridge, comprising:

[0011] a. Simulate and determine component parameters;

[0012] b. Generate a finite - element structural analysis model;

[0013] c. Conduct structural analysis and calculation;

[0014] d. Export the calculation results of model family (α);

[0015] e. Export the calculation results of model family (n);

[0016] f. Conduct structural model inspection;

[0017] g. Optimize the component cross - section and check the bearing capacity;

[0018] Among them, for the step a of simulating and determining component parameters, it specifically includes the following steps:

[0019] Step S1: According to the design data, conduct preliminary architectural design of the landscape bridge, investigate whether the design location is suitable for using an inclined - tower cable - stayed landscape bridge, determine the distance between the bridge - end supports of the landscape bridge according to the actual requirements and landscape effect, that is, the span l of the bridge, and determine the axis y1(x) of the bridge deck bending;

[0020] Step S2: According to the bridge - deck axis and load, equivalent the bridge deck into a common straight bridge deck, project the bridge - deck axis on the bridge - deck plane and the load on the bridge deck onto the vertical plane. The projection of the bridge - deck axis on the vertical plane, that is, the equivalent bridge - deck axis, is the intersection line of the bridge - deck plane and the vertical plane, and the projection of the load, that is, the equivalent load, is q’(x) = ∫q(x)dy;

[0021] Step S3: According to the equivalent bridge deck and bridge - deck load, calculate the height of the bridge tower and the positions of each cable point h1, h2... hn according to the common cable - stayed bridge.

[0022] Optionally, for the step a of simulating and determining component parameters, it specifically further includes the following steps:

[0023] Step S4: Assume that the cable strength is infinite and the number of cables is the same as that in the equivalent - bridge design in step S3, conduct the design of the actual curved bridge deck, and according to the static equilibrium calculation of the inclined - tower bridge, obtain the inclination - angle range [α1, α2] of the inclined tower;

[0024] The method of static equilibrium calculation is: assume that the cable strength is infinite, regard the horizontal curved bridge deck as an arch. For each given inclination angle α of the inclined tower, it can be determined that there is and only one unique inclination angle β of the cable. According to the vertical force F_vertical of the cable obtained in step S3 and the inclination angle β of the cable, the horizontal component force in the cable can be obtained as F_horizontal = F_vertical / tanβ.

[0025] Project the inclined tower 4 onto the bridge deck plane to obtain the horizontal sub-arch of the inclined tower 4. Apply F transversely to the horizontal sub-arch model of the inclined tower to calculate whether it meets the ultimate bearing capacity state. The minimum α value that can meet the horizontal sub-arch bearing capacity is α1.

[0026] The arch model formed by the transverse action of F on the bridge deck plane is calculated to see whether it meets the ultimate bearing capacity state of the bridge deck. The maximum α value that can meet the bearing capacity of the bridge deck is α2.

[0027] Step S5: According to the inclination angle range of the inclined tower described in step S4, in the first design analysis, it is assumed that the inclination angle α between the inclined tower and the horizontal plane is the maximum allowable inclination angle α2;

[0028] Step S6: Divide the bridge deck and the inclined tower into n segments evenly according to the horizontal projection length, where the value range of n is [1, n2], wherein the upper limit of the number of segments n2 is determined by the minimum spacing allowed by the construction operation and engineering experience, and n = n2 is assumed in the first design analysis;

[0029] Step S7: According to the segmentation method of step S6, the end points of each bridge deck and the inclined tower on the same horizontal plane are used as the cable end points to determine the number of cables. The cable cross section is initially selected based on engineering experience. Under normal circumstances, the diameter of the cable cross section is generally 10 cm. The size of the cable cross section is directly related to the length and weight of the bridge deck and the number of cables. For example, a cable 5 with a diameter of 12 cm has an axial force of 500 t, and a cable 5 with a diameter of 7 cm has an axial force of 200 t.

[0030] Optionally, the step b. generating a finite element structural analysis model specifically comprises the following steps:

[0031] Step S8: Determine the spatial coordinates of the endpoints of each component according to the component parameters in steps S2-S7, and compile the information of the spatial position, physical properties, cross-sectional properties, and structural boundary conditions of each component into a command file that can be recognized by finite element analysis software such as ANSYS or MIDAS;

[0032] Step S9: according to the command file containing the preliminary design model information in step S8, the command file is read in finite element analysis software such as ANSYS or MIDAS, and the span l, the arc bridge deck axis y1(x), the inclined tower inclination angle α and the inclined tower cable point positions h1, h2...hn are calculated according to the landscape bridge;

[0033] The curved bridge deck and inclined tower are evenly divided into n sections, the end points of each section are connected to determine the position of the cables, the component cross-section information, component material information, and structural boundary conditions are read, a finite element structural analysis model is generated, and the structural force analysis and calculation is performed according to the uniformly distributed pedestrian load on the bridge deck.

[0034] Optionally, the structural analysis calculation c specifically includes the following steps:

[0035] Step S10: According to Steps S1 - S9, read the command stream of the model establishment and analysis process in the finite element analysis software to generate a new command file. The main control parameters are the calculation span l of the landscape bridge, the in - plane rise f1 of the arc - shaped bridge deck, the height h of the cable points of the inclined tower, the inclination angle α of the inclined tower in the horizontal plane, and the number of horizontal segments n of the bridge deck and the inclined tower. Here, n also represents the number of cables of the cable - stayed landscape bridge with an inclined tower.

[0036] When one of the above - mentioned main parameters is different while the rest are the same, this series of models is called a model family. There can be certain differences in information such as the cross - section dimensions, physical properties, and boundary conditions of the components within the model family. Reasonable design is carried out according to the calculation results, and the characteristics of the cable - stayed landscape bridge with an inclined tower are regarded as related to the function F(l, f1, h, α, n).

[0037] Optionally, for step d, exporting the calculation results of the model family (α) specifically includes the following steps:

[0038] Step S11: According to the structural analysis in Steps S9 and S10, if there are cables under compression or not under force in the analysis results, first, reduce the inclination angle α of the inclined tower, re - assign values to generate a data file containing the command stream of the analysis model, and iteratively execute Step S9 for this group of model families (α) and export the calculation results of the model family (α).

[0039] Step S12: According to the analysis results of Step S9, set the cable tension threshold [T1, T2]. The values of the upper and lower limits T1 and T2 of the threshold are determined by the material of the cable, the initially selected cross - section form, and the actual stress conditions.

[0040] When all the cables in the results exported by the finite element analysis are under tension and the tension is within the threshold range, it is considered that the initially obtained structural model meets the structural stress requirements. Select the model with the smallest variance of cable tension in the calculation results of this model family (α), and its parameter α is used as the theoretically optimal inclination angle of the inclined tower.

[0041] Optionally, for step e, exporting the calculation results of the model family (n) specifically includes the following steps:

[0042] Step S13: If the finite element calculation results derived from steps S9 - S12 cannot meet the requirements of step S12, then adjust the number of segments n of the bridge deck and the inclined tower, reconstruct a new model family (n), taking the approximately converged parameter α in step S12 as known, re - assign n, generate a data file containing the analysis model command stream, and iteratively execute step S9 for the new model family (n). When, in the results derived from the finite element analysis, all stay cables are in tension and the tension is within the range of the stay - cable tension threshold, it is considered that the initially obtained structural model meets the structural stress requirements. Select the model with the smallest variance of stay - cable tension from the calculation results of this model family (n), and its parameter n is used as the theoretically optimal number of stay cables;

[0043] Step S14: If the finite element calculation results derived from steps S9 - S13 cannot meet the requirements of steps S12 and S13, then manually correct the in - plane axis y1(x) of the arc - shaped bridge deck and the in - plane tower axis y2(x) of the inclined tower in step S9 according to the differences in the calculation results, and re - execute steps S9 - S14.

[0044] Optionally, the f, structural model inspection specifically includes the following steps:

[0045] Step S15: Based on the structural model described in steps S9 - S14, on the basis of its reasonable stress, check whether the structure of this structural model meets the reasonable service requirements according to engineering experience and construction feasibility conditions. If not, manually correct the characteristic parameters of the inclined - tower cable - stayed landscape bridge and execute steps S9 - S14.

[0046] Optionally, the g, component section optimization and bearing capacity check specifically includes the following steps:

[0047] Step S16: According to the structural model described in step S15, if the structure meets the actual service requirements, then further optimize the design of the component sections and complete the bearing capacity check.

[0048] Optionally, in step S3, the method for calculating the height of the bridge tower and the positions of each cable point according to a general cable - stayed bridge is as follows: According to the equivalent load on the beam and the equivalent bending moment on the beam, determine the vertical component forces of each stay cable, then according to the bearing capacity of the stay cable, determine the horizontal component forces of the stay cable, thereby determining the stay - cable angle, and finally, according to the stay - cable angle and the beam span, determine the optimal position at the top of the stay cable.

[0049] Optionally, in step S4, the inclination angle range [α1, α2] is restricted by factors such as the type of the bridge, the construction location, the navigation requirements, and the load conditions. It is initially determined by the site conditions, and the calculation of the inclination angle range [α1, α2] should simultaneously meet the requirements of earthquake resistance, wind resistance, stability, and deformation under the current specifications.

[0050] In summary, the beneficial technical effects of the present application are as follows: The design method improves the disadvantages in the traditional landscape bridge design process, such as difficulty in finding the shape of the bridge, improper structural force, and waste of extra materials. By applying this design method, the manpower input in the design process can be significantly reduced, and the digital means can be used to perform rapid and efficient parametric iterative design on the target designed bridge, striving to seek the optimal solution in the design process, reducing the time cost input of designers, improving efficiency, and having good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a structural schematic diagram of the asymmetric inclined tower type cable-stayed landscape bridge of the present application;

[0052] Figure 2 It is a side view schematic diagram of the asymmetric inclined tower type cable-stayed landscape bridge of the present application;

[0053] Figure 3 It is a top view schematic diagram of the asymmetric inclined tower type cable-stayed landscape bridge of the present application;

[0054] Figure 4 It is a design flow chart for simulating and determining component parameters in the present application;

[0055] Figure 5 It is a flow chart for generating a finite element structural analysis model and performing structural analysis calculations in the present application.

[0056] Description of reference numerals: 1, approach bridge; 2, curved bridge deck; 3, bridge end support; 4, inclined tower; 5, cable; 6, ordinary straight bridge deck. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] The following is a further detailed description of the present application in conjunction with the attached Figures 1-5 drawings.

[0058] The embodiment of the present application discloses an asymmetric inclined tower type cable-stayed landscape bridge. Referring to Figure 1 , Figure 2 , Figure 3 , the asymmetric inclined tower type cable-stayed landscape bridge includes an approach bridge 1, a curved bridge deck 2, a bridge end support 3, an inclined tower 4, a pier (not shown), and a cable 5. Among them, the approach bridge 1 is located at both ends of the curved bridge deck 2. One end of the approach bridge 1 is connected to the road, and the other end is connected to the curved bridge deck 1 at the bridge end support 3. Both ends of the curved bridge deck 1 are connected to the bridge end support 3. The side of the curved bridge deck 2 away from the inclined tower 4 is connected to the cable 5. The axis of the curved bridge deck 1 is a curve, deviating towards one side of the connection line of the two bridge end supports 3. The beam bottom cross beam of the curved bridge deck 1 is a trapezoidal variable cross-section beam to improve the torsional resistance of the bridge deck itself.

[0059] Among them, the bridge-end fulcrum 3 is a giant concrete pier, rigidly connected to the curved bridge deck 1 to provide resistance to bending moment; the lower end of the inclined tower 4 is connected to the bridge pier, and the upper end is the fixed point of the cable 5. The bridge pier is rigidly connected to the ground; the cable 5 is a large steel cable, one end of which is connected to the top of the inclined tower 4, and the other end is connected to one side of the curved bridge deck 2. Among them, the fixed positions of the cables 5 from the middle to both ends of the curved bridge deck 1 gradually decrease with respect to the inclined tower 4.

[0060] Furthermore, in order to achieve the rapid and efficient parametric iterative design of the above-mentioned asymmetric inclined tower cable-stayed landscape bridge, the present embodiment discloses a design method for an asymmetric inclined tower cable-stayed landscape bridge, which is specifically as follows:

[0061] Refer to Figure 4 , Figure 5 A design method for an asymmetric inclined tower cable-stayed landscape bridge includes the following steps:

[0062] a. Simulate and determine the component parameters. Specifically, it includes the following steps:

[0063] Step S1: According to the design data, conduct a preliminary architectural design of the landscape bridge, investigate whether the design location is suitable for using an inclined tower cable-stayed landscape bridge, determine the distance between the bridge-end fulcrums of the landscape bridge, that is, the span l of the bridge, according to the actual requirements and landscape effects, and determine the axis y1(x) of the bridge deck bending.

[0064] Step S2: Refer to Figure 3 , according to the bridge deck axis and load, equivalent the bridge deck into a common straight bridge deck 6, project the bridge deck axis on the bridge deck plane and the load on the bridge deck onto the vertical plane. The projection of the bridge deck axis on the vertical plane, that is, the equivalent bridge deck axis, is the intersection line of the bridge deck plane and the vertical plane, and the projection of the load, that is, the equivalent load, is q’(x) = ∫q(x)dy.

[0065] Step S3: According to the equivalent bridge deck and bridge deck load, calculate the height of the bridge tower and the positions of each cable point h1, h2... hn according to a common cable-stayed bridge;

[0066] Among them, the method for calculating the height of the bridge tower and the positions of each cable point according to a common cable-stayed bridge is as follows: according to the equivalent load on the beam, equivalent the bending moment on the beam, determine the vertical component forces of each cable, and then according to the bearing capacity of the cable, determine the horizontal component forces of the cable, thereby determining the cable angle. Finally, according to the cable angle and the beam span, determine the optimal position of the top of the cable.

[0067] Step S4: Assuming that the cable strength is infinite and the number of cables is the same as that of the equivalent bridge design in step S3, the actual curved bridge deck is designed. According to the static equilibrium calculation of the inclined tower bridge, the inclination angle range [α1, α2] of the inclined tower is obtained; the inclination angle range [α1, α2] is limited by factors such as the type of bridge, construction location, navigation requirements, and load conditions. It is first preliminarily determined by the site conditions. The calculation of the inclination angle range [α1, α2] must simultaneously meet the requirements of earthquake resistance, wind resistance, stability, and deformation under the current specifications.

[0068] The method for static equilibrium calculation is: assuming that the strength of the cable 5 is infinite, the horizontal curved bridge deck is regarded as an arch, and for each given inclination angle α of an inclined tower, it can be determined that there is only one unique cable inclination angle β. According to the cable inclination angle β and the vertical force Fvert of the cable 5 obtained in step S3, it can be concluded that the horizontal component force in the cable 5 is Fhorizontal=Fvertical / tanβ.

[0069] Project the inclined tower 4 onto the bridge deck plane to obtain the horizontal sub-arch of the inclined tower 4. Apply F transversely to the horizontal sub-arch model of the inclined tower 4 to calculate whether it meets the ultimate bearing capacity state. The minimum α value that can meet the horizontal sub-arch bearing capacity is α1.

[0070] The arch model formed by the transverse action of F on the bridge deck plane is calculated to see whether it meets the ultimate bearing capacity state of the bridge deck. The maximum α value that can meet the bearing capacity of the bridge deck is α2.

[0071] Step S5: According to the inclination angle range of the inclined tower described in step S4, in the first design analysis, it is assumed that the inclination angle α between the inclined tower and the horizontal plane is the maximum allowable inclination angle α2.

[0072] Step S6: Divide the bridge deck and the inclined tower into n sections evenly according to the horizontal projection length, where the value range of n is [1, n2], where the upper limit of the number of sections n2 is determined by the minimum spacing allowed by the construction operation and engineering experience. In the first design analysis, it is assumed that n = n2, where the empirical maximum value of n2 is 30, which depends on the specific engineering conditions.

[0073] Step S7: According to the segmentation method of step S6, the end points of each bridge deck and the inclined tower on the same horizontal plane are used as the cable end points to determine the number of cables. The cable cross section is initially selected based on engineering experience. Under normal circumstances, the diameter of the cable cross section is generally 10 cm. The size of the cable cross section is directly related to the length and weight of the bridge deck and the number of cables. For example, a cable 5 with a diameter of 12 cm has an axial force of 500 t, and a cable 5 with a diameter of 7 cm has an axial force of 200 t.

[0074] b. Generate a finite element structural analysis model. The specific steps include:

[0075] Step S8: Determine the spatial coordinates of the endpoints of each component according to the component parameters in Steps S2 - S7, and compile the information on the spatial positions, physical properties, cross-sectional attributes, and structural boundary conditions of each component into a command file recognizable by finite element analysis software such as ansys or midas.

[0076] Step S9: According to the command file recorded with the preliminary design model information in Step S8, read the command file in finite element analysis software such as ansys or midas, and calculate the calculated span l of the landscape bridge, the arc-shaped bridge deck axis y1(x), the inclination angle α of the inclined tower, and the positions h1, h2... hn of the cable points on the inclined tower;

[0077] Divide the arc-shaped bridge deck and the inclined tower into n segments on average, connect the endpoints of each segment to determine the cable positions, read the cross-sectional information of the components, the material information of the components, and the content of the structural boundary conditions, generate a finite element structural analysis model, and perform structural stress analysis and calculation according to the uniform pedestrian load on the bridge deck.

[0078] c. Structural analysis and calculation. Specifically, it includes the following steps:

[0079] Step S10: According to Steps S1 - S9, read the command flow of the model establishment and analysis process in the finite element analysis software, and generate a new command file. The main control parameters are the calculated span l of the landscape bridge, the in-plane rise f1 of the arc-shaped bridge deck, the height h of the cable points on the inclined tower, the inclination angle α of the inclined tower in the horizontal plane, and the number of horizontal segments n of the bridge deck and the inclined tower, which also represents the number of cables of the inclined tower type cable-stayed landscape bridge;

[0080] When one of the above main parameters is different while the other parameters are the same, this series of models is called a model family. There can be certain differences in the cross-sectional dimensions, physical properties, boundary conditions, etc. of the components within the model family. Reasonably design according to the calculation results. The characteristics of the inclined tower type cable-stayed landscape bridge are regarded as related to the function F(l, f1, h, α, n).

[0081] d. Export the calculation results of the model family (α). Specifically, it includes the following steps:

[0082] Step S11: According to the structural analysis in Steps S9 and S10, if there are cables under compression or not under force in the analysis results, first reduce the inclination angle α of the inclined tower, re-assign values to generate a data file containing the command flow of the analysis model, and iteratively execute Step S9 for this group of model families (α) and export the calculation results of the model family (α);

[0083] Step S12: According to the analysis results in Step S9, set the cable tension thresholds [T1, T2]. The values of the threshold upper and lower limits T1 and T2 are determined by the material of the cable, the initially selected cross-sectional form, and the actual stress situation;

[0084] When the cables in the results derived from the finite element analysis are all under tension and the tension is within the threshold range, it is considered that the initially obtained structural model meets the structural force requirements. Select the model with the smallest variance of cable tension in the calculation results of this model family (α), and its parameter α is used as the theoretically optimal inclination angle of the inclined tower.

[0085] e. Derive the calculation results of the model family (n). Specifically, it includes the following steps:

[0086] Step S13: If the finite element calculation results derived in steps S9 - S12 do not meet the requirements of step S12, then adjust the number of segments n of the bridge deck and the inclined tower to rebuild a new model family (n). Taking the approximately converged parameter α in step S12 as known, re - assign n, generate a data file containing the analysis model command stream, and iteratively execute step S9 for the new model family (n). When the cables in the results derived from the finite element analysis are all under tension and the tension is within the cable tension threshold range, it is considered that the initially obtained structural model meets the structural force requirements. Select the model with the smallest variance of cable tension in the calculation results of this model family (n), and its parameter n is used as the theoretically optimal number of cables.

[0087] Step S14: If the finite element calculation results derived in steps S9 - S13 do not meet the requirements of steps S12 and S13, then manually correct the axis y1(x) of the curved bridge deck in the plane and the tower axis y2(x) of the inclined tower in the plane in step S9 according to the differences in the calculation results, and re - execute steps S9 - S14.

[0088] f. Structural model inspection. Specifically, it includes the following steps:

[0089] Step S15: Based on the structural model described in steps S9 - S14, check whether the structure of this structural model meets the reasonable usage requirements according to engineering experience and construction feasibility conditions on the basis of its reasonable force. If not, manually correct the characteristic parameters of the inclined - tower cable - stayed landscape bridge and execute steps S9 - S14.

[0090] g. Component cross - section optimization and bearing capacity check. Specifically, it includes the following steps:

[0091] Step S16: According to the structural model described in step S15, if the structure meets the actual usage requirements, then further optimize the design of the component cross - section and complete the bearing capacity check.

[0092] Furthermore, the construction method of the above - mentioned asymmetric inclined - tower cable - stayed landscape bridge mainly includes the following steps:

[0093] Step P1: At both ends of the curved bridge deck 2, construct the bridge - end supports 3, and during the concrete pouring process, reserve the connectors connected to the curved bridge deck 2.

[0094] Step P2: Support with a hydraulic jack and complete the casting construction of the inclined tower 4 below the height of the curved bridge deck 2.

[0095] Step P3: When constructing the curved bridge deck 2, adopt the construction method from both sides to the middle, set up temporary supports below the curved bridge deck 2, and at the same time, continue the construction of the inclined tower 4.

[0096] Step P4: First, connect and fix the inclined tower 4 and the two side surfaces at both ends of the curved bridge deck 2 through the cable 5.

[0097] Step P5: When constructing the curved bridge deck 2 and the inclined tower 4, tie the cable points in sequence from both sides of the bridge deck to the mid-span and from the bottom of the inclined tower 4 to the top of the inclined tower 4 during construction.

[0098] Step P6: Fix the terminal of the inclined tower 4 and the middle section of the curved bridge deck 2 in sequence.

[0099] Step P7: Re-tension each cable 5 symmetrically in sequence to ensure that each cable 5 does not exit the working state, and slowly remove the support system.

[0100] Step P8: Conduct secondary tensioning, slowly tension all the cables 5 synchronously to make the axial force of the cables 5 reach their design values.

[0101] Step P9: Use a total station to check the spatial position of the nodes and finally adjust the shape of the cable-stayed bridge through tensioning.

[0102] Step P10: After the inspection is completed and all the test data are qualified, the construction of the asymmetric inclined-tower cable-stayed landscape bridge is completed.

[0103] In summary, the present design method improves the disadvantages such as difficult bridge shape finding, improper structural stress, and waste of redundant materials in the traditional landscape bridge design process. By applying this design method, the manpower input in the design process can be greatly reduced, and the target designed bridge can be quickly and efficiently parametrically iteratively designed by using digital means, striving to seek the optimal solution in the design process, reducing the time cost input of designers, improving efficiency, and having good economic and social benefits.

[0104] The above are all the preferred embodiments of this application. The protection scope of this application is not limited by this. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A design method for an asymmetric inclined tower cable-stayed landscape bridge, characterized in that Including: a. Simulate and determine component parameters; b. Generate a finite element structural analysis model; c. Conduct structural analysis calculations; d. Export the calculation results of the model family (α); e. Export the calculation results of the model family (n); f. Conduct structural model inspection; g. Optimize the component cross-section and check the bearing capacity; Among them, for the step a of simulating and determining component parameters, it specifically includes the following steps: Step S1: According to the design data, conduct a preliminary architectural design of the landscape bridge, investigate whether the design location is suitable for using an inclined tower cable-stayed landscape bridge, determine the distance between the bridge end supports of the landscape bridge according to the actual requirements and landscape effects, that is, the bridge span l, and determine the axis y1(x) of the bridge deck bending; Step S2: According to the bridge deck axis and the load, equivalent the bridge deck into an ordinary straight bridge deck, project the bridge deck axis on the bridge deck plane and the load on the bridge deck onto the vertical plane. The projection of the bridge deck axis on the vertical plane, that is, the equivalent bridge deck axis, is the intersection line of the bridge deck plane and the vertical plane, and the projection of the load, that is, the equivalent load, is q’(x) = ∫q(x)dy; Step S3: According to the equivalent bridge deck and the bridge deck load, calculate the height of the bridge tower and the positions of each cable point h1, h2... hn according to an ordinary cable-stayed bridge; Step S4: Assume that the cable strength is infinite and the number of cables is the same as that used in the equivalent bridge design in Step S3, conduct the design of the actual curved bridge deck, and obtain the inclination angle range [α1, α2] of the inclined tower according to the static equilibrium calculation of the inclined tower bridge; Step S5: According to the inclined tower inclination angle range described in Step S4, assume that the inclination angle α between the inclined tower and the horizontal plane is the allowable maximum inclination angle α2 during the first design analysis; Step S6: Divide the bridge deck and the inclined tower into n segments on average according to the horizontal projection length. The value range of n is [1, n2], where the upper limit n2 of the number of segments is determined by the minimum distance allowed for construction operations and engineering experience. Assume n = n2 during the first design analysis; Step S7: According to the segmentation method in Step S6, determine the number of cables with the endpoints of each segment of the bridge deck and the inclined tower on the same horizontal plane as the cable endpoints; Among them, for the step b of generating a finite element structural analysis model, it specifically includes the following steps: Step S8: Determine the spatial coordinates of the endpoints of each component according to the component parameters in Steps S2 - S7, and compile the information of the spatial position, physical properties, cross-section attributes, and structural boundary conditions of each component into a command file recognizable by finite element analysis software; Step S9: According to the command file recording the preliminary design model information in Step S8, read the command file in the finite element analysis software, and obtain the calculation span l of the landscape bridge, the arc-shaped bridge deck axis y1(x), the inclined tower inclination angle α, and the positions of the inclined tower cable points h1, h2... hn; It is to divide the arc-shaped bridge deck and the inclined tower into n segments on average, connect the endpoints of each segment to determine the cable positions, read the component cross-section information, component material information, and structural boundary condition content, generate a finite element structural analysis model, and conduct structural stress analysis calculations according to the uniform pedestrian load on the bridge deck; Among them, for the step c of conducting structural analysis calculations, it specifically includes the following steps: Step S10: According to Steps S1 - S9, read the command stream of the model establishment and analysis process in the finite element analysis software to generate a new command file, where the main control parameters are the calculation span l of the landscape bridge, the in - plane rise f1 of the arc - shaped bridge deck, the height h of the cable points on the inclined tower, the inclination angle α of the inclined tower in the horizontal plane, and the number of horizontal segments n of the bridge deck and the inclined tower. When one of the above - mentioned main parameters is different while the rest are the same, this series of models is called a model family, and the characteristics of the inclined - tower cable - stayed landscape bridge are regarded as related to the function F(l, f1, h, α, n). Among them, for step d, deriving the calculation results of the model family (α) specifically includes the following steps: Step S11: According to the structural analysis in Steps S9 and S10, if there are cables under compression or cables not under force in the analysis results, first, reduce the inclination angle α of the inclined tower, re - assign values to generate a data file containing the command stream of the analysis model, and iteratively execute Step S9 for this group of model families (α) and export the calculation results of the model family (α). Step S12: According to the analysis results of Step S9, set the cable tension threshold [T1, T2], and the values of the upper and lower limits T1 and T2 of the threshold are determined by the material of the cable, the initially selected cross - section form, and the actual stress conditions. When all the cables in the results derived from the finite element analysis are under tension and the tension is within the threshold range, it is considered that the initially obtained structural model meets the structural stress requirements. Select the model with the smallest variance of cable tension in the calculation results of this model family (α), and its parameter α is used as the theoretically optimal inclination angle of the inclined tower. Among them, for step e, deriving the calculation results of the model family (n) specifically includes the following steps: Step S13: If the finite element calculation results derived from Steps S9 - S12 cannot meet the requirements of Step S12, then adjust the number of segments n of the bridge deck and the inclined tower to reconstruct a new model family (n). Taking the approximately convergent parameter α in Step S12 as known, re - assign n, generate a data file containing the command stream of the analysis model, and iteratively execute Step S9 for the new model family (n). When all the cables in the results derived from the finite element analysis are under tension and the tension is within the cable tension threshold range, it is considered that the initially obtained structural model meets the structural stress requirements. Select the model with the smallest variance of cable tension in the calculation results of this model family (n), and its parameter n is used as the theoretically optimal number of cables. Step S14: If the finite element calculation results derived from Steps S9 - S13 cannot meet the requirements of Steps S12 and S13, then manually correct the in - plane axis y1(x) of the arc - shaped bridge deck and the tower axis y2(x) in the plane of the inclined tower in Step S9 according to the differences in the calculation results, and re - execute Steps S9 - S14.

2. The design method of an asymmetric inclined tower cable-stayed landscape bridge according to claim 1, characterized in that: For step f, the structural model inspection specifically includes the following steps: Step S15: According to the structural model described in Steps S9 - S14, on the basis of its reasonable stress, check whether the structure of this structural model meets the reasonable use requirements according to engineering experience and construction feasibility conditions. If not, manually correct the characteristic parameters of the inclined - tower cable - stayed landscape bridge and execute Steps S9 - S14.

3. A design method for an asymmetric inclined tower cable-stayed landscape bridge according to claim 2, characterized in that: The optimization of the cross-section of the g member and the bearing capacity check specifically include the following steps: Step S16: According to the structural model described in Step S15, if the structure meets the actual use requirements, further optimize the design of the cross-section of the member and complete the bearing capacity check.

4. The design method of an asymmetric inclined tower cable-stayed landscape bridge according to claim 1, characterized in that: In Step S3, the method for calculating the height of the bridge tower and the positions of each cable point according to the ordinary cable-stayed bridge is as follows: Based on the equivalent load on the beam and the equivalent bending moment on the beam, determine the vertical component forces of each stay cable, and then, according to the bearing capacity of the stay cable, determine the horizontal component forces of the stay cable, thereby determining the angle of the stay cable. Finally, according to the angle of the stay cable and the span of the beam, determine the optimal position of the top of the stay cable.

5. A design method for an asymmetric inclined tower cable-stayed landscape bridge according to claim 1, characterized in that: In Step S4, the inclination angle range [α1, α2] is restricted by factors such as the type of the bridge, the construction site, the navigation requirements, and the load conditions. It is initially determined by the site conditions. The calculation of the inclination angle range [α1, α2] should simultaneously meet the requirements of earthquake resistance, wind resistance, stability, and deformation.

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