Supporting structure of V-shaped supporting aqueduct and design method

Abstract

The invention discloses a supporting structure of a V-shaped supporting aqueduct and a design method, and relates to the technical field of water conservancy projects. The V-shaped support structure is arranged between the bottom of the upper water conveying structure and the top of the pier column; the V-shaped support structure comprises two bifurcated sections at the top, and the tops of the bifurcated sections are rigidly connected with the upper water conveying structure; in the direction from the lower end to the upper end of each bifurcated section, the two bifurcated sections are gradually and oppositely away from each other; the two branch sections are symmetrically arranged along the cross section of the upper water conveying structure. A plurality of pier columns are sequentially arranged in the length direction of the upper water conveying structure. Every two adjacent V-shaped supporting structures are arranged in a spaced mode. And the bending curvature of the forked section is gradually reduced from the lower end to the upper end of the forked section. By the adoption of the scheme, the numerical value and range of hogging moment at the fulcrum can be greatly reduced through the V-shaped support structure, the midspan deflection is reduced, and the whole aqueduct structure is safer and more durable while the spanning capacity is reserved.

Description

Technical Field

[0001] The present invention relates to the technical field of water conservancy engineering, and in particular to a supporting structure and a design method of a V-shaped supporting aqueduct. Background Art

[0002] In recent years, my country has seen a surge in water conservancy project construction, accelerating the development of a national water network. Aqueducts are the most widely used cross-sectional structures in water diversion and regulation projects. However, building aqueducts in mountainous areas often presents challenges, such as excessive overhead heights and crossing wide and gentle canyons, highways, railways, and navigable rivers. The spanning capacity of simply supported beam aqueducts, with a maximum span of approximately 40 meters, is insufficient. New aqueduct structural systems and supporting design methods are urgently needed to significantly enhance this spanning capacity.

[0003] Prestressed concrete continuous rigid-frame bridges are a common bridge type used in highway and railway applications. Due to their mechanical characteristics, such as a continuous beam and the consolidation of piers, beams, and foundations, they offer exceptionally strong spanning capabilities. Furthermore, they can be constructed using a hanging basket to minimize impacts on structures below. Their application in aqueduct construction holds broad promise in the water conservancy industry. Currently, the Qianzhong Irrigation District and the Letan Reservoir Irrigation District have leveraged the structure and design methods of continuous rigid-frame highway bridges to construct aqueducts such as the Caodipo, Xujiawan, and Hongshuihe aqueducts.

[0004] While the aforementioned project achieved improved spanning capacity, the single-support T-shaped rigid frame structure still presented challenges such as a large negative bending moment zone, significant mid-span deformation, and difficulty in variable-section construction. This structural type was particularly problematic when the piers were relatively low. Therefore, a new aqueduct structure and design method that could maintain the spanning capacity of current solutions while also improving structural safety and durability was a pressing issue in this field. Summary of the Invention

[0005] In order to address the deficiencies of the prior art, the present invention aims to provide a support structure and design method for a V-shaped supported aqueduct. By adopting this solution, the value and range of the negative bending moment at the support point can be greatly reduced through the V-support structure, and the mid-span deflection can be reduced, making the entire aqueduct structure safer and more durable while retaining the spanning capacity.

[0006] The present invention is achieved through the following technical solutions: A supporting structure for a V-shaped supporting aqueduct, characterized by comprising: pier column; A V-bracing structure, the V-bracing structure being arranged between the bottom of the upper water delivery structure and the top of the pier; The V-bracing structure includes two bifurcated sections at the top, and the top of the bifurcated section is rigidly connected to the upper water supply structure; from the lower end to the upper end of the bifurcated section, the two bifurcated sections gradually move away from each other; the two bifurcated sections are symmetrically arranged along the cross section of the upper water supply structure.

[0007] In the above scheme, the V-bracing structure is rigidly connected to the upper water conveyance structure through two bifurcated sections, while the lower end of the V-bracing structure is fixedly connected or hinged to the pier by a support. In this way, the existing single-support T-shaped rigid frame structure can be changed. A double support is formed by one supporting structure through two bifurcated sections, and they are symmetrical and away from each other from the middle. The V-bracing structure can be dynamically optimized according to the load, so that it can not only bear the deadweight load of the aqueduct and the water load at the same time, thereby reducing the calculated span of the aqueduct, but also greatly reduce the value and range of the negative bending moment at the support, and reduce the mid-span deflection; the bifurcated section is preferably an arc-shaped structure, so that the force on the V-bracing structure and the upper water conveyance structure is more reasonable than that of a single-support continuous rigid frame aqueduct, while retaining the spanning capacity, making the entire aqueduct structure safer and more durable. The upper water conveyance structure is a concrete or prestressed concrete continuous aqueduct with a single-chamber or double-chamber structure of uniform cross-section, equipped with vents, and a rectangular, U-shaped, circular, or trapezoidal cross-section, selected based on hydraulic characteristics. The piers are connected to the foundation structure, which includes piles and slab foundations.

[0008] A further solution is to provide a plurality of piers along the length of the upper water conveyance structure, with adjacent V-bracing structures spaced apart. This means that each V-bracing structure is independently supported and connected only to the upper water conveyance structure, while adjacent V-bracing structures are not connected, facilitating the independent distribution of multiple V-bracing structures on the continuous beam aqueduct.

[0009] A further solution is to reduce stress concentration on the bifurcated section. The bifurcated section is formed as an arc or a line with a gradual curvature from its lower end to its upper end. That is, the bifurcated section with a circular arc or a line with a gradual curvature forms a rigid connection node with the lower edge of the main beam support; the arc with a constant curvature is more preferably used.

[0010] In a further embodiment, a bifurcation angle between the bifurcation section and the cross section of the upper water delivery structure is 30°≤θ≤120°.

[0011] In a further solution, the two bifurcated sections are integrally formed with the upper water delivery structure.

[0012] In a further solution, the V-bracing structure is made of at least one of ordinary reinforced concrete, prestressed reinforced concrete, steel-concrete composite structure or steel-concrete.

[0013] In a further solution, the upper water delivery structure is a concrete or prestressed concrete continuous aqueduct with a uniform cross-section and a single-box and single-chamber or double-box and double-chamber structure.

[0014] In a further embodiment, the present invention further provides a method for designing a V-shaped support aqueduct, comprising the following steps: S1: Determine the span scheme of the V-shaped support aqueduct according to external conditions. The span scheme includes determining the piers in the support structure and the maximum span length of the V-support structure. ; S2: Determine the size parameters and cross-sectional type of the upper water delivery structure based on hydraulics and engineering experience; S3: Then establish a V-brace point optimization mathematical model to select and determine the optimal span length of the V-brace structure under ideal conditions. And the length of the upper water supply structure on both sides of the V-support structure and ; A V-bracing angle optimization mathematical model is established to select and determine the optimal bifurcation angle θ and height h of the bifurcation section of the V-bracing structure under ideal conditions; S4: Based on the preliminary scheme determined in steps S1-S3, determine the line shape of the bifurcation section, the arrangement scheme of the prestressed steel tendons, and the temporary support type; S5: A three-dimensional finite element model of the V-support aqueduct was then established for structural simulation. Through stress control, the values of , and θ were continuously optimized and adjusted until the stress and deformation met the requirements of the concrete design specifications, thereby determining the parameters of the upper water supply structure and the V-support structure.

[0015] In a further embodiment, the V-brace point optimization mathematical model includes the following calculation steps: Under the working conditions of maximum double cantilever and considering only the deadweight, calculate , their respective self-weight bending moments ; Under the working conditions of water flow and only considering the water load, calculate Water load bending moment for each segment ; Finally, according to the function and bring in , thereby determining the optimal 、 .

[0016] In a further embodiment, the V-brace angle optimization mathematical model includes the following calculation steps: Under the working conditions of eccentric compression and symmetrical reinforcement, calculate and the rotational stiffness of each of the two bifurcated segments to determine the maximum bending moment; Determine the height H of the entire support structure based on the actual terrain and geological conditions on site, and calculate the reinforcement area ; Finally, according to the function and bring in T, thus obtaining θ and h that meet the project cost; in the above formula, b is the width of the upper water supply structure, C t is the cost of concrete, C g The cost of steel bars.

[0017] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. This invention discloses a support structure and design method for a V-shaped aqueduct. By employing this solution, the invention reduces the distance between the aqueduct main beam supports through the provision of appropriate V-shaped supports, thereby reducing negative bending moments at the pier tops and positive bending moments at mid-span, increasing the rigidity of the aqueduct structure, and improving overall structural integrity. Its modular design accommodates spans of 30-90 meters, combining long-span capabilities with seismic resistance, providing an efficient solution for aqueduct projects spanning complex terrains such as highways, canyons, and rivers.

[0018] 2. The present invention discloses a support structure and design method for a V-shaped support aqueduct. By adopting this solution, the V-support structure is fixedly connected to the upper water conveyance structure, and the horizontal rigidity is greater than that of a single-pier rigid frame aqueduct; and the upper water conveyance structure adopts a uniform cross-section design, which is convenient for construction; the design method proposed by the present invention can fully utilize the material properties and ensure the safety and durability of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. In the drawings: Figure 1 A schematic structural diagram of a V-shaped support aqueduct provided by the present invention; Figure 2 A front view of a V-shaped support aqueduct provided by the present invention; Figure 3 This is a design drawing of the working condition of a single V-shaped support under its own weight load provided by the present invention; Figure 4 This is the working condition design drawing of a single V-shaped support under water load provided by the present invention; Figure 5 The calculation design diagram of the rotational stiffness of a single V-shaped support provided by the present invention; Figure 6 A calculation design diagram for optimizing the angle of a single V-shaped support provided by the present invention; Figure 7 This is a cross-sectional dimension diagram of the beam unit in Example 3 provided by the present invention; Figure 8 In Example 3 provided for the present invention, there is a V-bracing span arrangement diagram; Figure 9 This is a span arrangement diagram without V-bracing in Example 3 provided by the present invention; Figure 10 This is the maximum double-cantilever bending moment distribution diagram in Example 3 provided by the present invention; Figure 11 This is the bending moment distribution diagram of the completed bridge in Example 3 provided by the present invention.

[0020] Markings and corresponding parts names in the accompanying drawings: 1-upper water supply structure, 3-V-support structure, 4-ventilation hole, 5-pier column. DETAILED DESCRIPTION

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0022] Example 1: This example 1 provides a V-shaped supporting aqueduct support structure, such as Figure 1-Figure 2 Shown; including:

[0023] Pier 5; A V-bracing structure 3, the V-bracing structure 3 being arranged between the bottom of the upper water delivery structure 1 and the top of the pier 5; The V-bracing structure 3 includes two bifurcated sections at the top, and the top of the bifurcated section is rigidly connected to the upper water supply structure 1; from the lower end to the upper end of the bifurcated section, the two bifurcated sections gradually move away from each other; the two bifurcated sections are symmetrically arranged along the cross section of the upper water supply structure 1.

[0024] In the above scheme, the V-bracing structure 3 is rigidly connected to the upper water conveyance structure 1 through two bifurcated sections, and the lower end of the V-bracing structure 3 is fixedly connected or hinged to the pier 5. In this way, the existing single-support T-shaped rigid frame structure type can be changed. A double support is formed by one supporting structure through two bifurcated sections, and they are symmetrical and away from each other from the middle. The V-bracing structure 3 can be dynamically optimized according to the load, so that it can not only bear the deadweight load and water load of the aqueduct at the same time, thereby reducing the calculated span of the aqueduct, but also greatly reduce the value and range of the negative bending moment at the support, and reduce the mid-span deflection; and the bifurcated section is preferably an arc-shaped structure, so that the force on the V-bracing structure 3 and the upper water conveyance structure 1 is more reasonable than that of a single-support continuous rigid frame aqueduct, while retaining the spanning capacity, making the entire aqueduct structure safer and more durable. The upper water conveyance structure 1 is a concrete or prestressed concrete continuous aqueduct with a single-chamber or double-chamber structure of uniform cross-section, designed according to hydraulic conditions. It is equipped with vents 4 and has a rectangular, U-shaped, circular, or trapezoidal cross-section, selected based on hydraulic characteristics. Piers 5 are connected to the foundation structure, which includes piles and a slab foundation.

[0025] In this embodiment, a plurality of piers 5 are sequentially arranged along the length of the upper water delivery structure 1; and two adjacent V-bracing structures 3 are spaced apart. That is, each V-bracing structure 3 is independently supported and connected only to the upper water delivery structure 1, while two adjacent V-bracing structures 3 are not connected, facilitating the independent distribution of multiple V-bracing structures 3 on the continuous beam aqueduct.

[0026] In this embodiment, to reduce stress concentration on the bifurcated section, the bifurcated section is formed as an arc or a line with a gradual curvature from its lower end to its upper end. That is, the bifurcated section with a circular arc or a line with a gradual curvature forms a rigid connection node with the lower edge of the main beam support; more preferably, the bifurcated section is formed as an arc with a constant curvature.

[0027] In this embodiment, the bifurcation angle between the bifurcation section and the cross section of the upper water delivery structure 1 is 30°≤θ≤120°.

[0028] In this embodiment, the two bifurcated sections are integrally formed with the upper water delivery structure 1 .

[0029] In this embodiment, the V-bracing structure 3 is made of at least one of ordinary reinforced concrete, prestressed reinforced concrete, steel-concrete composite structure or steel-concrete.

[0030] In this embodiment, the upper water delivery structure 1 is a concrete or prestressed concrete continuous aqueduct with a uniform cross-section and a single-box and single-chamber or double-box and double-chamber structure.

[0031] Example 2: This example 2 provides a design method for a V-shaped support aqueduct, such as Figure 3-Figure 6 As shown, the following specific steps are included: 1. Preliminary determination of the V-shaped support aqueduct using V-bracing structure 3. First, collect the external conditions below the aqueduct that affect the V-bracing arrangement, such as railways, roads, houses, rivers, etc., and then select the V-shaped support pier position and determine it according to the constraints. The span plan for the aqueduct was initially determined. The spans should be arranged symmetrically, not encroaching on the space of the underlying buildings unless necessary to save on demolition costs and highlight the advantages of hanging basket construction.

[0032] 2. Determine the internal dimensions of the aqueduct based on hydraulic calculations, and preliminarily determine the dimensions of the aqueduct concrete structure based on engineering experience. The general wall thickness can be 35 to 100 cm, and the cross-sectional shape can be U-shaped, circular, egg-shaped, rectangular, etc.

[0033] 3. According to the V-bracing point optimization mathematical model proposed by the present invention, select and determine the 、 , wherein the upper water supply structure 1 between two adjacent V-support structures 3 is a section, and a V-support structure 3 and a section of the upper water supply structure 1 on both sides are a unit, It is the length of the upper water supply structure 1 on one side of the V-support structure 3. is the distance between the upper ends of the two bifurcated segments in the V-bracing structure 3, is the length of the upper water delivery structure 1 on the other side of the V-bracing structure 3. In this way, the parameter design of several units can be quickly calculated.

[0034] 4. According to the V-bracing angle optimization mathematical model proposed in the present invention, the bifurcation angle θ and height h of the three bifurcation sections of the V-bracing structure that meet the engineering requirements are selected and determined.

[0035] 5. Draw the preliminary structure of the V-shaped support aqueduct according to the above layout parameters. The V-shaped support and the main beam should be connected by straight lines, arcs or gentle curves, and the arc connection method is preferred.

[0036] 6. According to the load balance method and (M 自 +M 水 ) distribution law to preliminarily determine the prestressed steel tendon arrangement plan.

[0037] 7. Preliminary design of construction plan based on the length of each section of 3 to 5 meters, determine the construction sequence and temporary support type.

[0038] 8. Build a three-dimensional finite element model for structural simulation. Stress control principles: For Grade 1-3 aqueducts, the internal surface must be strictly controlled to prevent cracks, while the external surface must be controlled to prevent cracks. For Grade 4-5 aqueducts, the internal surface must be controlled to prevent cracks.

[0039] 9. According to the simulation structure, continuously optimize and adjust the aqueduct and θ until the stress and deformation meet the requirements of the concrete design specifications and the aqueduct structure is determined.

[0040] 10. Finally, complete the detailed structural design of the aqueduct and the lower foundation design based on engineering experience and relevant specifications.

[0041] In the above steps, the mathematical model for optimizing the V-brace point in the third point is: First set the conditions , L= + ; Then calculate the working conditions of the maximum double cantilever and only consider the deadweight effect, respectively Each self-weight bending moment ;like Figure 3 As shown. Among them: ; In the above formula, is the deadweight load, and l is any point in the upper water supply structure 1.

[0042] Then, under the working conditions of water flow and only considering the water load, the calculations are made respectively. Water load bending moment for each segment ;like Figure 4 As shown. Among them: ; The calculation process of the above bending moment also includes the following steps: 1. Figure 5 The middle structure is constrained by rigid arms at points B and C to obtain the basic system of the displacement method. BA is a single-span beam with one end fixed and the other simply supported, BC is a single-span beam with both ends fixed, and CD is a single-span beam with one end fixed and the other directional.

[0043] 2. Calculate the bending moment at the fixed end: This is the bending moment at the rod end caused by the external load on the basic system of the displacement method, as shown in the formula below. The positive value is when the lower part is under tension.

[0044] 3. Calculation of rotational stiffness: such as: .

[0045] 4. Distribution coefficient: Calculate the distribution coefficient of nodes B and C; .

[0046] 5. Allocation and transfer: first relax node C, then relax node B, for a total of two rounds of allocation.

[0047] 6. Final bending moment: The final rod end bending moment is obtained by adding the fixed end bending moment and the distributed or transferred bending moment according to the superposition principle.

[0048] Among them, the bending moment at the fixed end is: ; Distributed torque: ; Moment distribution process: ; in, According to the above formula, the respective self-weight bending moment and water load bending moment can be obtained , and finally according to the function and bring in , thereby determining the optimal .

[0049] In the above steps, the mathematical model for optimizing the V-brace angle in the fourth point is: First set the conditions and ;like Figure 6 As shown; The rotational stiffness is then calculated as: , , , ; Partition coefficient: ; Where, M = max[μBEM1, μCEM2]; ; Determined based on the actual terrain and geological conditions on site: ;and ; Finally, according to the function and bring in T , thus obtaining θ and h that meet the project cost; in the above formula, b is the width of the upper water supply structure 1, C t is the cost of concrete, C g The cost of steel bars.

[0050] Example 3: This example 3 is further optimized based on example 2, and provides an implementation scheme for modeling verification through a finite element model, such as Figure 7-11 shown.

[0051] 1. Midas finite element modeling process: 1.1 Two-unit cross-section dimensions: The aqueduct in this calculation adopts a rectangular cross-section with a total width of 10.5m and a total height of 6.5m. The top plate thickness of the aqueduct is 0.4m, the bottom plate thickness is 0.7m, and the left and right side walls are both 0.8m thick. Figure 7 The net height of the water-passing section is 5.4m and the net width is 6.9m.

[0052] 1.2 The aqueduct calculated in this study adopts a V-bracing structure with a total length of 220m. The V-bracing height is uniformly 8.7m, and the spans are symmetrically distributed: 29m (side span) - 22m (V-bracing) - 48m (middle span) - 22m (V-bracing) - 48m (middle span) - 22m (V-bracing) - 29m (side span) (see Figure 8 Based on the above parameters and the cross-sectional dimensions of the beam element in Section 1.1 (total width 10.5m, total height 6.5m, water-passing section width 6.9m, height 5.4m), a finite element model was established using Midas Civil (see Figure 8 (b)).

[0053] 1.3 The aqueduct in this calculation adopts a non-V-bracing structure and only the maximum double-cantilever condition is calculated. The total length is 68m. When there is no V-bracing, piers are used instead of V-bracing. The pier height is 8.7m. The span distribution is symmetrical: 34m (side span) - 34m (side span) (see Figure 9Based on the above parameters and the cross-sectional dimensions of the beam element in Section 1.1 (total width 10.5m, total height 6.5m, water-passing section width 6.9m, height 5.4m), a finite element model was established using Midas Civil (see Figure 9 ((b)).

[0054] 2. Analysis of Midas finite element modeling results 2.1 Comparison of the maximum double cantilever bending moment of aqueducts with and without V-bracing: Midas Civil conducted a comparative analysis of the bending moment distribution of aqueduct structures under the maximum double cantilever working condition (considering only the deadweight effect). The results show that: without V-bracing: the main beam has the maximum negative bending moment at the pier, which is 304,056 kN·m (see Figure 10 (b) There is no peak-cutting effect in the pier area. In the case of V-bracing, the maximum negative moment is transferred to the V-bracing node, and a significant peak-cutting effect occurs in the middle of the V-bracing, with the moment reduced to 139,140 kN·m (see Figure 10 (a) shows a 119% reduction compared to the case without the V-bracing, and the overall stress distribution of the structure is more uniform. The V-bracing effectively optimizes the bending moment distribution and reduces local stress peaks, validating its design rationale.

[0055] 2.2 Bending moment analysis of aqueduct with V-braces in completed state: The bending moment distribution of the aqueduct structure in the completed state and the bending moment distribution when water is flowing are analyzed by Midas Civil. Figure 11 (a) Bending moment distribution of the completed bridge; Figure 11 (b) is the bending moment distribution after water flow. The results show that under the action of deadweight, the maximum negative bending moment of 90688 kN.m occurs at the mid-span V-bracing, and the bending moment at the mid-span V-bracing shows an obvious peak reduction phenomenon. The maximum positive bending moment of 84061 kN.m will appear between the mid-span V-bracing and the side span V-bracing. Figure 11 As shown in (a). Under the action of self-weight + water load, the maximum negative bending moment of 146678kN.m occurs at the mid-span V-bracing, and the bending moment at the mid-span V-bracing shows a significant peak reduction phenomenon. The maximum positive bending moment of 137566kN.m will appear between the mid-span V-bracing and the side span V-bracing. Figure 11 (b)

[0056] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A V-shaped supporting aqueduct support structure, characterized in that: include: Pier (5); A V-bracing structure (3), the V-bracing structure (3) being arranged between the bottom of the upper water delivery structure (1) and the top of the pier (5); The V-bracing structure (3) comprises two bifurcated sections at the top, the top of the bifurcated section being rigidly connected to the upper water supply structure (1); from the lower end to the upper end of the bifurcated section, the two bifurcated sections gradually move away from each other; and the two bifurcated sections are symmetrically arranged along the cross section of the upper water supply structure (1).

2. The support structure of a V-shaped support aqueduct according to claim 1, characterized in that: A plurality of piers (5) are sequentially arranged along the length direction of the upper water delivery structure (1); and two adjacent V-support structures (3) are arranged at intervals.

3. The support structure of a V-shaped support aqueduct according to claim 1, characterized in that: The bifurcation segment is in a direction from the lower end to the upper end thereof, and is an arc line or a gradually changing curvature line.

4. The support structure of a V-shaped support aqueduct according to claim 1, characterized in that: The bifurcation angle between the bifurcation section and the cross section of the upper water conveyance structure (1) is 30°≤θ≤120°.

5. A V-shaped support aqueduct support structure according to any one of claims 1 to 4, characterized in that: The two bifurcated sections are integrally formed with the upper water delivery structure (1).

6. A V-shaped support aqueduct support structure according to any one of claims 1 to 4, characterized in that: The constituent material of the V-bracing structure (3) is at least one of ordinary reinforced concrete, prestressed reinforced concrete, steel-concrete composite structure or steel-concrete.

7. A V-shaped support aqueduct support structure according to any one of claims 1 to 4, characterized in that: The upper water conveyance structure (1) is a concrete or prestressed concrete continuous aqueduct with a uniform cross-section, single-box, single-chamber or double-box, double-chamber structure.

8. A method for designing a V-shaped support aqueduct, characterized in that: The following steps are involved: S1: Determine the span scheme of the V-shaped support aqueduct according to external conditions, the span scheme includes determining the maximum span length of the pier (5) in the support structure and the V-support structure (3) ; The support structure is the support structure according to any one of claims 1 to 7; S2: Determine the size parameters and cross-sectional shape of the upper water delivery structure (1) based on hydraulics and engineering experience; S3: Then establish the V-bracing point optimization mathematical model to select and determine the optimal span length of the V-bracing structure (3) under ideal conditions. and the length of the upper water delivery structure (1) on both sides of the V-support structure (3) and ; A mathematical model for optimizing the V-bracing angle is established to select and determine the optimal V-bracing structure (3) bifurcation angle θ and height h of the bifurcation segment under ideal conditions; S4: Based on the preliminary scheme determined in steps S1-S3, determine the line shape of the bifurcation section, the arrangement scheme of the prestressed steel tendons, and the temporary support type; S5: Then a three-dimensional finite element model of the V-shaped support aqueduct was established for structural simulation, and stress control was used to continuously optimize and adjust the structure. 、 and θ until the stress and deformation meet the requirements of the concrete design specification, thereby determining the parameters of the upper water supply structure and the V-bracing structure (3).

9. The method for designing a V-shaped support aqueduct according to claim 8, characterized in that: The V-brace point optimization mathematical model includes the following calculation steps: Under the working conditions of maximum double cantilever and considering only the deadweight, calculate 、 Each self-weight bending moment ; Under the working conditions of water flow and only considering the water load, calculate 、 Water load bending moment for each segment ; Finally, according to the function and bring in , thereby determining the optimal 、 .

10. The method for designing a V-shaped support aqueduct according to claim 8, characterized in that: The V-brace angle optimization mathematical model includes the following calculation steps: Under the working conditions of eccentric compression and symmetrical reinforcement, calculate 、 and the rotational stiffness of each of the two bifurcated segments to determine the maximum bending moment; Determine the height H of the entire support structure based on the actual terrain and geological conditions on site, and calculate the reinforcement area ; Finally, according to the function and bring in , thus obtaining θ and h that meet the project cost; in the above formula, b is the width of the upper water supply structure, For concrete cost, The cost of steel bars.

Images