Corrugated steel web curve box girder bending and twisting whole process analysis method, terminal and medium

Abstract

The invention provides a corrugated steel web curve box girder bending and twisting whole process analysis method, a terminal and a medium, and belongs to the technical field of corrugated steel web curve box girders. According to the method for analyzing the whole bending and torsion process of the corrugated steel web curve box girder, the stress state of the corrugated steel web curve box girder is stripped into an anti-bending subsystem and an anti-torsion subsystem, the anti-bending subsystem is subjected to anti-bending whole-process loop iteration analysis, and the anti-torsion subsystem is subjected to anti-torsion whole-process loop iteration analysis; establishing the relation between the anti-bending subsystem and the anti-torsion subsystem of the corrugated steel web curve box girder, and obtaining the bending and torsion whole process loop iteration analysis of the corrugated steel web curve box girder. According to the method for analyzing the whole bending and twisting process of the corrugated steel web curve box girder, the whole bending and twisting process is analyzed, the calculation accuracy is improved, and more various response results can be obtained and analyzed through whole-process iteration.

Description

Technical Field

[0001] The invention belongs to the technical field of curved box girders with corrugated steel webs, and in particular relates to a method for analyzing the entire bending and torsion process of a curved box girder with corrugated steel webs, a terminal and a medium. Background Art

[0002] The traditional concrete box girder is composed of a top plate, a bottom plate, a web plate, a diaphragm, a support beam, etc. The top plate, the bottom plate, the web plate, the diaphragm, the support beam, etc. are usually made of reinforced concrete structure. The traditional concrete box girder gradually exposed some problems during use, and the durability was poor. The corrugated steel web curved box girder uses corrugated steel plates as the webs of the box girder to replace the traditional concrete webs. The top plate and the bottom plate are reinforced concrete structures, and longitudinal steel bars, transverse steel bars, prestressed steel bars, etc. are provided. The corrugated steel plate has high shear strength and stability, high prestressing efficiency, good three-dimensional flexural characteristics, and relatively light weight, which can effectively reduce the deadweight of the box girder, reduce the material consumption of the lower structure, and reduce production costs. With the promotion of the corrugated steel web curved box girder, the research on its mechanical properties has become more and more in-depth, but most of them are only concentrated in the elastic stage, and there are few studies on the nonlinear stage. Under the influence of factors such as curves and external prestress, the research on the nonlinear stage of the corrugated steel web curved box girder is more complicated. In addition, under the action of the bending-torsion coupling characteristics of the curved beam itself, even if the shear lag effect is not considered, the cross-sectional stress is no longer equal along the transverse direction. Especially after entering the plastic stage, the yield starting points of the stress at each point along the height and width of the cross section are different. The stress state of the structure becomes very complicated, which greatly increases the difficulty of nonlinear analysis. Since the external prestressed steel bars in the curved beam will produce different prestresses on the inside and outside of the curve, and there is no deformation coordination relationship between their strain and the strain of the adjacent concrete, the complexity of the nonlinear solution process is further increased. Summary of the invention

[0003] The purpose of the present invention is to provide a method, terminal and medium for analyzing the whole process of bending and torsion of a curved box girder with a corrugated steel web, aiming to solve the problem that the analysis of the curved box girder with a corrugated steel web is difficult in the nonlinear stage.

[0004] To achieve the above object, the technical solution adopted by the present invention is to provide a method for analyzing the bending and torsion of a curved box girder with a corrugated steel web, comprising the following steps: S1. Separate the stress state of the curved box girder with corrugated steel web into a bending resistance subsystem and a torsion resistance subsystem; S2. Conduct cyclic iterative analysis of the whole bending process of the bending resistance subsystem; S3, perform cyclic iterative analysis of the whole process of torsion resistance on the torsion resistance subsystem; S4. Establish the connection between the bending resistance subsystem and the torsion resistance subsystem of the curved box girder with corrugated steel webs; S5. Obtain the cyclic iterative analysis of the whole bending and torsion process of the curved box girder with corrugated steel web.

[0005] In a possible implementation, in step S2, in the case of the anti-bending subsystem, the curved box girder with corrugated steel webs is equivalent to a straight beam, the torque effect caused by the curvature of the beam axis is eliminated, and the effect of the equivalent straight beam in resisting the bending moment caused by the load is analyzed.

[0006] In a possible implementation, under the action of bending moment, the stress of the equivalent straight beam is divided into four stages, namely, the first bending stage, the second bending stage, the third bending stage, and the fourth bending stage. In the first bending stage, the concrete does not crack. In the second bending stage, the bottom plate cracks, the tensile strain of the longitudinal and transverse steel bars of the bottom plate is less than the specified value, and the compressive strain of the top plate is less than or equal to the specified value. In the third bending stage, the tensile strain of the longitudinal and transverse steel bars is greater than or equal to the specified value, the tensile strain of the prestressed steel bars in the body is less than or equal to the specified value, and the compressive strain of the top plate is less than or equal to the specified value. In the fourth bending stage, the tensile strain of the longitudinal and transverse steel bars of the bottom plate is greater than or equal to the specified value, the tensile strain of the prestressed steel bars in the body is greater than or equal to the specified value, and the compressive strain of the top plate is greater than or equal to the specified value, until the compressive strain of the longitudinal and transverse steel bars of the bottom plate is greater than or equal to the specified value and the concrete top plate is broken.

[0007] In a possible implementation, in step S3, in the case of the torsion-resistant subsystem, the curved box girder with corrugated steel webs is equivalent to a straight beam, and the torque effect caused by the curvature of the beam axis is analyzed.

[0008] In a possible implementation, the total torque of the equivalent straight beam under the action of torque includes the torque borne by the bottom plate and the top plate, the torque borne by the corrugated steel web, and the torque borne by the external prestressed tendons.

[0009] In one possible implementation, the curvature of the beam axis of the curved box girder with corrugated steel webs is constant, and bending moment and torque will be generated simultaneously under a certain load. The bending moment and torque generated at this time correspond to the same load level, and the effects of the bending moment under the anti-bending subsystem and the effects of the torque under the anti-torsion subsystem are analyzed separately and superimposed.

[0010] In a possible implementation, in a curved box girder with corrugated steel webs, under the coupling of bending and torsion, the bottom plate and the top plate are simultaneously compressed and sheared, and in the ultimate failure state, the bottom plate / top plate is broken.

[0011] In a possible implementation, according to step S5, the stress increment of the external prestressed steel bars inside and outside the curved box girder with corrugated steel webs is calculated, and the prestress increment at any point along the cross section of the curved box girder with corrugated steel webs is calculated.

[0012] A terminal is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the methods described above when executing the computer program.

[0013] A computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the methods described above are implemented.

[0014] The beneficial effects of the whole-process analysis method of bending and torsion of a curved box girder with a corrugated steel web provided by the present invention are: Compared with the prior art, the stress state of the curved box girder with corrugated steel web is separated into a bending-resistant subsystem and a torsion-resistant subsystem, and cyclic iterative analysis is performed on the whole bending process of the anti-bending subsystem and the whole torsion-resistant subsystem respectively. The cyclic iterative analysis improves the accuracy of data analysis, and establishes a connection between the bending-resistant subsystem and the torsion-resistant subsystem of the curved box girder with corrugated steel web. The cyclic iterative analysis of the whole bending process of the anti-bending subsystem is combined with the cyclic iterative analysis of the whole torsion process of the torsion-resistant subsystem to obtain the cyclic iterative analysis of the whole bending and torsion process of the curved box girder with corrugated steel web, realizing the whole bending and torsion process analysis of the curved box girder with corrugated steel web, and can obtain and analyze a variety of response results. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of the bending and torsion state of a curved box girder with corrugated steel webs used in an embodiment of the present invention; Figure 2 A schematic diagram of the bending-resistant subsystem of the curved box girder with corrugated steel webs adopted in an embodiment of the present invention; Figure 3 A schematic diagram of the anti-torsion subsystem of the corrugated steel web curved box girder used in an embodiment of the present invention; Figure 4 A flow chart of the whole process cyclic iterative calculation of the bending resistance subsystem of the corrugated steel web curved box girder adopted in the embodiment of the present invention; Figure 5 A flow chart of the whole process cyclic iterative calculation of the anti-torsion subsystem of the corrugated steel web curved box girder adopted in the embodiment of the present invention; Figure 6 A flow chart of cyclic iterative calculation of the entire bending and torsion process of a curved box girder with corrugated steel webs adopted in an embodiment of the present invention; Figure 7 It is a schematic diagram of the first stage of the bending resistance force analysis of the curved box girder with corrugated steel webs adopted in the embodiment of the present invention; Figure 8 A schematic diagram of the second stage of force analysis of the bending resistance of the curved box girder with corrugated steel webs used in the embodiment of the present invention; Figure 9 It is a schematic diagram of the third stage of the bending resistance force analysis of the curved box girder with corrugated steel webs adopted in the embodiment of the present invention; Figure 10 It is a schematic diagram of the fourth stage of stress analysis of the bending resistance of the curved box girder with corrugated steel webs adopted in the embodiment of the present invention.

[0017] In the figure: 1. Top plate; 2. Corrugated steel web; 3. Bottom plate. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] Please refer to Figure 1 to Figure 10 A specific implementation method of the whole process analysis method of the bending and torsion of a curved box girder with a corrugated steel web provided by the present invention is now described, comprising the following steps: S1. Separate the stress state of the curved box girder with corrugated steel web into a bending resistance subsystem and a torsion resistance subsystem; S2. Conduct cyclic iterative analysis of the whole bending process of the bending resistance subsystem; S3, perform cyclic iterative analysis of the whole process of torsion resistance on the torsion resistance subsystem; S4. Establish the connection between the bending resistance subsystem and the torsion resistance subsystem of the curved box girder with corrugated steel webs; S5. Obtain the cyclic iterative analysis of the whole bending and torsion process of the curved box girder with corrugated steel web.

[0020] The present invention provides a method for analyzing the whole process of bending and torsion of a curved box girder with a corrugated steel web. Compared with the prior art, the stress state of the curved box girder with a corrugated steel web is separated into a bending resistance subsystem and a torsion resistance subsystem, and cyclic iterative analysis is performed on the whole process of bending resistance of the anti-bending subsystem and the whole process of torsion resistance of the torsion resistance subsystem respectively. The cyclic iterative analysis improves the accuracy of data analysis, establishes a connection between the bending resistance subsystem and the torsion resistance subsystem of the curved box girder with a corrugated steel web, combines the cyclic iterative analysis of the whole process of bending resistance of the anti-bending subsystem with the cyclic iterative analysis of the whole process of torsion resistance of the torsion resistance subsystem, obtains the cyclic iterative analysis of the whole process of bending and torsion of the curved box girder with a corrugated steel web, realizes the whole process analysis of bending and torsion of the curved box girder with a corrugated steel web, and can obtain and analyze a variety of response results.

[0021] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 1 to Figure 10 In step S2, in the case of the anti-bending subsystem of the curved box girder with corrugated steel webs, the torque generated by the inherent characteristics of the curved box girder with corrugated steel webs mainly comes from the curvature of the beam axis. The curved box girder with corrugated steel webs is equivalent to a straight beam to eliminate the torque generated by the curvature of the beam axis. In this case, the curved box girder with corrugated steel webs only resists the bending moment caused by the load, and the effect of the equivalent straight beam resisting the bending moment caused by the load is analyzed.

[0022] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 2 , Figure 4 , Figure 7 to Figure 10 , Under the action of external load bending moment, the stress of the equivalent straight beam is divided into four stages, namely the first bending stage, the second bending stage, the third bending stage, and the fourth bending stage. In the first bending stage, the concrete did not crack. In the second bending stage, the bottom plate 3 cracked, the tensile strain of the longitudinal and transverse steel bars of the bottom plate 3 was less than the specified value, and the compressive strain of the top plate 1 was less than or equal to the specified value. In the third bending stage, the tensile strain of the longitudinal and transverse steel bars was greater than or equal to the specified value, the tensile strain of the internal prestressed steel bars was less than or equal to the specified value, and the compressive strain of the top plate 1 was less than or equal to the specified value. In the fourth bending stage, the tensile strain of the longitudinal and transverse steel bars of the bottom plate 3 was greater than or equal to the specified value, the tensile strain of the internal prestressed steel bars was greater than or equal to the specified value, and the compressive strain of the top plate 1 was greater than or equal to the specified value, until the compressive strain of the longitudinal and transverse steel bars of the bottom plate 3 was greater than or equal to the specified value and the concrete top plate 1 was broken.

[0023] When the curved box girder with corrugated steel web is equivalent to a straight beam, the stress conditions of the cross section of the curved box girder with corrugated steel web in these four stages are analyzed. In the stress analysis process, the various mechanical parameters and their meanings involved are as follows: h z is the total height of the section; h ps It is the distance from the point of action of the combined force of the prestressed tendons in the body to the compression edge of the section; h p It is the distance from the point of action of the combined force of the external prestressed tendons to the compression edge of the section; h 0 is the effective height of the section, h 0= h z -y s ξ is the height of the cross section relative to the compression zone, ξ= x / h 0,x is the height of the compression zone; the upper and lower flanges of the steel beam are converted into the steel bars in the top plate 1 and the bottom plate 3 respectively. y′ s The distance from the point of action of the combined force behind the steel bars in the top plate 1 and the bottom plate 3 to the compression edge of the section; y s are the distances from the position of the combined force action point behind the steel bars in the top plate 1 and the bottom plate 3 to the tensile edge of the section; y c It is the distance from the concrete combined force action point in the compression zone of the top plate 1 and the tension zone of the bottom plate 3 to the compression edge of the section; y ct It is the distance from the concrete combined force action point in the compression zone of the top plate 1 and the tension zone of the bottom plate 3 to the tension edge of the section; d c is the thickness of the top plate 1, d ct is the thickness of the bottom plate 3; d eq Take d eq = min( ξh 0, d c ); e is the strain value of the concrete compressive stress-strain relationship curve, that is, the abscissa of the curve; e c is the edge compressive strain of concrete in the compression zone of top plate 1; e ct is the tensile strain of the concrete edge in the tension zone of the bottom plate 3; e cr is the concrete cracking strain; e cu is the ultimate compressive strain of concrete; e t is the uniaxial tensile strain of concrete, e sy is the yield strain of the steel bar; e' s is the compressive strain at the point of action of the resultant force of the top plate 1 reinforcement (including the upper flange of the steel beam); e s is the tensile strain at the point of action of the resultant force of the bottom plate 3 reinforcement (including the lower flange of the steel beam); e p is the prestressed tendon strain; e 0 is the peak compressive strain of concrete; σ ′ s Corresponding to e' s Stress; σ s Corresponding to e s Stress; σ psis the stress of the prestressed tendons in the body; s pe is the initial effective stress of the external prestressed tendons; Δ s p It is the increment of external prestressed tendons; s ps The effective stress of the prestressed tendons in the body after considering the loss of prestress; C c is the resultant stress of concrete in the compression zone of top plate 1; C t is the resultant force of concrete stress in the tension zone of bottom plate 3; A′ s is the area of ​​top plate 1 reinforcement (including the upper flange of the steel beam); A s is the area of ​​the bottom plate 3 reinforcement (including the lower flange of the steel beam); A ps is the area of ​​the prestressed tendons in the body; A p is the area of ​​external prestressed tendons; b e is the effective distribution width of top slab 1 concrete; b et is the effective distribution width of concrete of bottom slab 3; E p is the elastic modulus of the prestressed tendons; E S is the elastic modulus of the steel bar; E c is the elastic modulus of concrete; M is the moment at the point of action of the resultant force on the concrete in the compression zone; f c is the axial compressive strength of concrete; f cr is the concrete cracking stress; f y is the yield strength of the steel bar; k is the slope of the steel bar hardening section; a 1 for .

[0024] Analysis of the stress conditions at the cross section of the curved box girder with corrugated steel webs in these four stages: The first stage of bending resistance, before concrete cracking, The axial force equilibrium equation of the cross section is: (1) The moment balance equation, (2) in, (3) (4) (5) (6) The second stage of bending resistance is after the concrete cracks and before the tensile reinforcement yields. The axial force equilibrium equation of the cross section is: (1) The moment balance equation, (2) in, (7) (8) (6) In the third stage of bending, after the tensile reinforcement yields and before the concrete reaches the peak compressive strain, The axial force equilibrium equation of the cross section is: (9) The moment balance equation, (10) In the fourth stage of bending, after the concrete reaches the peak compressive strain, The axial force equilibrium equation of the cross section is: (11) The moment balance equation, (12) in, (13) (14).

[0025] In the anti-bending subsystem, the static equilibrium equations at each stage include e c , Prestressed tendon increment and the relative compression zone height ξ. If the load is known, assume a prestressing tendon increment , find the other two unknown quantities, judge whether the accuracy of the assumed values ​​meets the requirements, and obtain the full process curves of the bending moment-curvature and load-prestress increment of the bending-resistant subsystem. matlab Programming calculation, the specific steps are: M1, assuming that the stress increment of an external prestressed tendon is Δ s , then the total stress of the prestressed tendon is s p = s pe +Δ s p ; M2. Divide the beam length n units, calculate the bending moment at each unit location based on the load M i ( i =1,2,···, n ), according to the geometric conditions, calculate the height of the external prestressed tendons at each unit location h pi ( i =1,2, ···, n ); M3, in s p Assume that the curved box girder with corrugated steel web is in the first stage of bending resistance, that is, before the concrete cracks, and combine formulas 1 to 6 to solve the first stage of bending resistance. n cross-sectional e ci and , and then according to the formula Available n The curvature of the cross section ϕ s ; M4, according to ϕ si Obtain e cti ,judge e cti Is it less than e cr If it is less than, it is still in the first stage of bending resistance, and the formulas 1 to 6 are combined to find the solution. Otherwise, it enters the second stage of bending resistance, and the formulas 1, 2, 6, 7, and 8 are combined to find the solution. ϕ si Obtain e ci , e si ,like e ci ≤ e 0, e si < e sy , it is still in the second stage of bending resistance, otherwise it enters the third stage of bending resistance. Combining formulas 9 and 10, according to the obtained ϕ si Obtain e ci , e si ,like e ci ≤ e 0. esi ≥ e sy and e psi ≤ e p , it is still in the third stage of bending resistance, otherwise it enters the fourth stage of bending resistance, and the formulas 11 to 14 are combined; M5, in the solution ϕ si Then, calculate the deflection of the turning block section and the mid-span section w A1 、w A2 ; M6. Calculate the elongation of the external prestressed tendon Δ l p and strain e p , and then the prestressed tendon stress is obtained in p and its increment Δ in p ; M7. Determine the hypothesized Δσ p and Δσ′ p Whether the difference meets the accuracy requirement (the accuracy requirement is set to 0.001), if not, modify Δσ p , using the calculated Δσ′ p Continue to re-execute the first step as an assumed value until the accuracy requirement is met.

[0026] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 3 , Figure 5 In step S3, in the case of the torsion-resistant subsystem, the curved box girder with corrugated steel webs is equivalent to a straight beam, which is considered to only bear the torque caused by the curvature of the beam axis, and the torque caused by the curvature of the beam axis of the equivalent straight beam is analyzed.

[0027] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 3 , Figure 5 Under the action of torque, the total torque of the equivalent straight beam includes the torque borne by the bottom plate 3 and the top plate 1, the torque borne by the corrugated steel web 2, and the torque borne by the external prestressed tendons.

[0028] When the curved box girder with corrugated steel web is equivalent to a straight beam, the stress condition at the cross section of the curved box girder with corrugated steel web is analyzed. In the torsion analysis process, the various mechanical parameters and their meanings involved are as follows: A 0c andA 0w They are 1 / 2 of the area enclosed by the center line of the shear flow; is the total cross-sectional area of ​​the external prestressed tendons; is the total cross-sectional area of ​​the prestressed tendons in the body; is the total cross-sectional area of ​​the longitudinal reinforcement; A c is the cross-sectional area of ​​the concrete part; is the shear stress of top plate 1 / bottom plate 3; is the shear stress of the corrugated steel web 2; is the average stress of the external prestressed tendons; is the average stress of the prestressed tendons in the body; is the average principal tensile stress of concrete; is the average principal compressive stress of concrete; is the average stress of the longitudinal reinforcement; is the average stress of the transverse reinforcement; It is the vertical distance from the torsion center to the bottom edge prestressed tendon; is the strain of the prestressed tendons in the body; is the strain of the external prestressed tendons; e l is the average strain of the longitudinal reinforcement; is the average strain of the transverse reinforcement; is the average tensile strain of the concrete oblique compression short column; is the average compressive strain of the concrete oblique compression short column; , are the maximum compressive strain and minimum compressive strain of the concrete oblique compression short column respectively; , are the maximum tensile strain and minimum tensile strain of the concrete oblique compression short column respectively; is the strain of the prestressed tendons in the body; is the softening coefficient of concrete; is the shear strain of the concrete slab; is the twist rate; d cd is the effective thickness of the concrete shear flow zone; d w is the thickness of the corrugated steel web 2; d cd0 is the neutral axis height of the axially compressed short column in the unified model of the equivalent straight beam, which is the value assumed at the beginning of the iterative calculation; is the value calculated by the formula; h It is the height between the center of the concrete top plate 1 section and the center of the bottom plate 3 section; b is the distance between the center lines of the corrugated steel web 2; d is the transverse spacing of prestressed tendons; Shear stress contributed to concrete; is the shear stress of the corrugated steel web 2; is the shear strain of the corrugated steel web 2; the two prestressed tendons are denoted as A and B, the subscript 1 represents the turning block position, 2 represents the mid-span position, A1 and B1 are the turning block positions, A2 and B2 are the mid-span positions, and correspondingly, the horizontal displacement (∆ v A ,∆ v B ), vertical displacement (∆ w A ,∆ w B ); At the steering block position, horizontal displacement (∆ v A1 ,∆ v B1 ), vertical displacement (∆ w A1 ,∆ w B1 ); at the mid-span position, horizontal displacement (∆ v A2 ,∆ v B2 ), vertical displacement (∆ w A2 ,∆ w B2 ), with (∆ v A1(2) ,∆ v B1(2) ) represents the horizontal displacement at the steering block position (mid-span position), (∆ w A1(2) ,∆ w B1(2) ) represents the vertical displacement at the steering block position (mid-span position); F wA1 is the vertical force of the torque generated by the prestressing of the prestressed tendon A at the turning block position section, F wB1 They are the vertical forces of the torque generated by the prestressing of the prestressed tendon B in the section at the turning block position; F vA1 is the horizontal force of the torque generated by the prestressing of the prestressed tendon A at the turning block position section. F vB1 They are the horizontal forces of the torque generated by the decomposition of the prestress of the section at the steering block position on the prestressed tendon B; F wA2 is the vertical force of the torque generated by the prestressing of the prestressed tendon A in the mid-span section, F wB2They are the vertical forces of the torque generated by the decomposition of the prestress of the section at the mid-span position on the prestressed tendon B; F vA2 is the horizontal force of the torque generated by the decomposition of the prestressed tendon A from the section at the mid-span position, F vB2 are the horizontal forces of the torque generated by the prestressing of the prestressed tendon B in the mid-span section; in addition, F wA1(2) , F vA1(2) , F wB1(2) , F vB1(2) To refer to F wA1 , F wB1 , F wA2 , F wB2 , F vA1 , F vB1 , F vA2 , F vB2 ; T is the total torque of the box girder; T c is the torque borne by the concrete part; T w is the torque borne by the corrugated steel web; T p is the torque borne by the external prestressed tendons, T pw and T pv are the torques resisting the vertical and horizontal forces respectively; T p1 is the total section torque resisted by the external prestressed tendons at the turning block position section, T p2 is the total moment of the section resisted by the external prestressed tendons in the mid-span section, T p1(2) To refer to T p1 , T p2 , L Calculate the length for the beam, k 0 is a constant between 0 and 1, is the rotation angle of the concrete shear element.

[0029] (15) A c =2 bd c (16) (17) (18) (19) (20) (twenty one) (twenty two) (twenty three) (twenty four) (25) (26) (27) In the case of the torsion-resistant subsystem, according to the above calculation formula, matlab Program, after entering known data, select variables e d When a certain value of is reached, the remaining variables can be solved iteratively through the effective equation by trial and error, and the value is increased according to a certain rule. e d value until e d Reach 0.0018, thereby iteratively calculating the values ​​of each unknown quantity in the entire torsion process.

[0030] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 1 to Figure 10 The curvature of the beam axis of the curved box girder with corrugated steel web is constant. Under a certain load, bending moment and torque will be generated at the same time. At this time, the bending moment and torque generated correspond to the same load level. The effect of the bending moment under the anti-bending subsystem and the effect of the torque under the anti-torsion subsystem are analyzed separately, and the vertical uniform load is superimposed. p Bending moment caused by M p and torque T p The formula is: (28) (29) in, R is the radius of the curved beam axis, 0 is the center angle of the curved beam, x The distance between the curved beam and the end point x The center angle of the position.

[0031] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 1 to Figure 10 In the curved box girder with corrugated steel web, under the coupling of bending and torsion, the bottom plate 3 and the top plate 1 are subjected to compression and shear at the same time. Under the ultimate failure state, the bottom plate 3 / top plate 1 is broken.

[0032] As a specific implementation method of the whole process analysis method of the corrugated steel web curved box girder bending and torsion provided by the present invention, please refer to Figure 1 to Figure 10 According to step S5, the stress increment of the external prestressed steel bars on the inner and outer sides of the curved box girder with corrugated steel webs is calculated, and the prestress increment at any point along the cross section of the curved box girder with corrugated steel webs is calculated.

[0033] Take a small unit from the center of the shear flow of the top plate 1 A ,neglect y Transverse deformation ( e y ), fiber compression and shear deformation in the z direction ( e z , c yz , c xz ), in the bending-resisting subsystem, the compressive strain of the top plate 1 under longitudinal compression is e c , the corresponding strain at the center of the shear flow is ; Shear strain of concrete in the xy plane in the torsion subsystem c c ,by c / 2 is the vertical axis, e As the horizontal axis, draw the strain Mohr circle according to the unit body A The strain state of the strain Mohr circle must have a point intersecting with the ordinate. According to the strain Mohr circle, the maximum compressive strain at the center of the shear flow of the top plate 1 of the corrugated steel web curved box girder is obtained. e maxd , converted to the maximum compressive strain on the top surface of top plate 1: e max ,when e max When >0.0033, the beam is damaged. (30) (31) If the section torque is known, the external load can be calculated by equations 33 and 34, and the section torque can be calculated by the iterative program of the anti-torsion subsystem. The load can be calculated, the bending moment can be calculated, and the anti-bending subsystem can be entered to continue the analysis. The calculation steps are as follows: N1. Divide the curved box girder with corrugated steel web into n Units, select a unit i , select a tiny e d Enter the anti-torsion subsystem iteration program to calculate the torque of this section T , back-calculate the external load according to equations 33 and 34 P ,Depend on P Calculation of bending moment M , enter the anti-bending subsystem iteration program; N2, the horizontal displacement of the prestressed tendon turning block obtained by the torsion-resistant subsystem (∆ v A1(2) ,∆ v B1(2) )(subscript 1 represents the steering block position, 2 represents the mid-span position) and vertical displacement (∆ w A1(2) ,∆ w B1(2) ), the vertical displacement (∆ w A1(1) ,∆ w B1(1) ), and superimpose the two to obtain the total horizontal displacement (∆ v A1(2) ,∆ v B1(2) ) and vertical displacement (∆ w A1(2) ,∆ w B1(2) ); N3. Calculate the elongation of the two external prestressed tendons A and B, and the strain increment of the two external prestressed tendons A and B. According to the constitutive relationship, the prestress increment Δ on the outside and inside of the curve can be obtained. s pA , Δ s pB , and then we can also get the coordinates of any point along the cross section of the corrugated steel web curved box girder y The prestress increment Δ s py ; N4, obtained from the bending resistance subsystem program n The concrete compressive strain at the compression edge of each unit section is output. i Where e cdi , e ci; The shear strain under torque at this position is obtained from the anti-torsion subsystem program c c , the maximum compressive strain of the top plate 1 of the corrugated steel web curved box girder is calculated e max ,like e max <0.0033, give e d Repeat the above calculation until e max >0.0033, then the unit i Destruction, ultimate load P ui ; N5. Continue to select units i +1, repeat the above steps and compare each unit i The ultimate load P ui , select the minimum value (worst case), its unit i The position is the failure section, and the relevant data in this case is output.

[0034] Based on the same inventive concept, an embodiment of the present application also provides a terminal. A specific implementation of a terminal is now described, including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the steps of any of the methods described above when executing the computer program.

[0035] Specifically, in this embodiment, the terminal may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The terminal may include, but is not limited to, a processor and a memory, and may include more components than the above structure, or a combination of certain components, or different components. For example, the terminal may also include input and output devices, network access devices, buses, etc.

[0036] The processor may be a central processing unit, or other general-purpose processors, digital signal processors, application-specific integrated circuits, field programmable gate arrays, or other programmable logic device discrete gates or discrete hardware components of transistor logic devices. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor. The memory may be an internal storage unit of the terminal, such as a hard disk or memory of the terminal. The memory may also be an external storage device of the terminal, such as a plug-in hard disk, a smart memory card, or a flash memory card equipped on the terminal.

[0037] Based on the same inventive concept, an embodiment of the present application also provides a computer-readable storage medium. A specific implementation of a computer-readable storage medium is now described. The computer-readable storage medium stores a computer program, which is characterized in that when the computer program is executed by a processor, the steps of any method described above are implemented.

[0038] Specifically, each functional unit in each embodiment of the present invention may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit. If the integrated module or unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium.

[0039] Based on this understanding, the present invention implements all or part of the processes in the above-mentioned implementation method, and can also be completed by instructing related hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned identification method can be implemented.

[0040] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for analyzing the entire bending and torsion process of a curved box girder with corrugated steel webs, characterized in that: The steps are as follows: S1. Separate the stress state of the curved box girder with corrugated steel web into a bending resistance subsystem and a torsion resistance subsystem; S2. Conduct cyclic iterative analysis of the whole bending process of the bending resistance subsystem; S3, perform cyclic iterative analysis of the whole process of torsion resistance on the torsion resistance subsystem; S4. Establish the connection between the bending resistance subsystem and the torsion resistance subsystem of the curved box girder with corrugated steel webs; S5. Obtain the cyclic iterative analysis of the whole bending and torsion process of the curved box girder with corrugated steel web.

2. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs according to claim 1, characterized in that: In step S2, in the case of the anti-bending subsystem, the curved box girder with corrugated steel webs is equivalent to a straight beam, the torque effect caused by the curvature of the beam axis is eliminated, and the effect of the equivalent straight beam in resisting the bending moment caused by the load is analyzed.

3. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs as claimed in claim 2, characterized in that: Under the action of bending moment, the stress of the equivalent straight beam is divided into four stages, namely the first bending stage, the second bending stage, the third bending stage and the fourth bending stage. In the first bending stage, the concrete did not crack. In the second bending stage, the bottom plate cracked, the tensile strain of the longitudinal and transverse steel bars of the bottom plate was less than the specified value, and the compressive strain of the top plate was less than or equal to the specified value. In the third bending stage, the tensile strain of the longitudinal and transverse steel bars was greater than or equal to the specified value, the tensile strain of the prestressed steel bars in the body was less than or equal to the specified value, and the compressive strain of the top plate was less than or equal to the specified value. In the fourth bending stage, the tensile strain of the longitudinal and transverse steel bars of the bottom plate was greater than or equal to the specified value, the tensile strain of the prestressed steel bars in the body was greater than or equal to the specified value, and the compressive strain of the top plate was greater than or equal to the specified value, until the compressive strain of the longitudinal and transverse steel bars of the bottom plate was greater than or equal to the specified value and the concrete top plate was broken.

4. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs according to claim 1, characterized in that: In step S3, in the case of the torsion-resistant subsystem, the curved box girder with corrugated steel webs is equivalent to a straight beam, and the torque effect caused by the curvature of the beam axis is analyzed.

5. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs as claimed in claim 4, characterized in that: The total torque of the equivalent straight beam under the action of torque includes the torque borne by the bottom plate and the top plate, the torque borne by the corrugated steel web and the torque borne by the external prestressed tendons.

6. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs according to claim 1, characterized in that: The curvature of the beam axis of the curved box girder with corrugated steel webs is constant. Under a certain load, bending moment and torque will be generated simultaneously. The bending moment and torque generated at this time correspond to the same load level. The effects of the bending moment under the anti-bending subsystem and the effects of the torque under the anti-torsion subsystem are analyzed separately and superimposed.

7. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs as claimed in claim 1, characterized in that: In the curved box girder with corrugated steel web, under the coupling action of bending and torsion, the bottom plate and top plate are subjected to compression and shear at the same time. Under the ultimate failure state, the bottom plate / top plate is broken.

8. The method for analyzing the bending and torsion of a curved box girder with corrugated steel webs as claimed in claim 1, characterized in that: According to step S5, the stress increment of the external prestressed steel bars on the inner and outer sides of the curved box girder with corrugated steel webs is calculated, and the prestress increment at any point along the cross section of the curved box girder with corrugated steel webs is calculated.

9. A terminal comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method described in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 8 are implemented.

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