High-position pool steel strand arrangement and tensioning scheme feasibility verification method

Abstract

The application discloses a high-position pool steel strand arrangement and tensioning scheme feasibility verification method, which comprises the following steps: on the basis of a ring prestress action mechanism, vertical stress distribution of an inner wall of a prestressed concrete pool body in a steel strand tensioning process is calculated, and a finite element software is used to carry out numerical simulation on the tensioning process, and the theoretical calculation and the numerical simulation are combined to verify the feasibility of the high-position pool steel strand arrangement and tensioning scheme. The application provides a theoretical basis and a feasibility verification means for a high-position pool steel strand arrangement and tensioning scheme design stage, can improve design efficiency, avoid ring cracks on an inner surface of a prestressed lining in a steel strand tensioning process, and enhance structural reliability.

Description

Technical Field

[0001] This invention belongs to the field of architectural construction design technology, specifically relating to a method for verifying the feasibility of steel strand arrangement and tensioning schemes for elevated water tanks. Background Technology

[0002] An elevated water tank is a type of outflow structure that combines water retention, overflow, and pressure regulation functions. The portion above ground is a prestressed concrete tank structure, while the underground portion is a conventional reinforced concrete tank structure.

[0003] During the tensioning of steel strands in prestressed concrete pools, tensile stress is generated along the axial direction of the pool's inner wall, leading to continuously distributed annular cracks and affecting structural reliability. Different cross-sectional areas, arrangement densities, and tensioning sequences of the steel strands all influence the vertical stress distribution on the inner wall of the prestressed concrete pool. Therefore, a feasibility verification method for the arrangement and tensioning scheme of steel strands in elevated water tanks is needed to improve the design efficiency of the steel strand arrangement and tensioning scheme and enhance the reliability of the pool structure. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for verifying the feasibility of steel strand arrangement and tensioning schemes in elevated water tanks. By combining theoretical calculations based on the annular prestressing mechanism with finite element numerical simulations, the feasibility of the steel strand arrangement and tensioning schemes in elevated water tanks is verified, thereby improving the design efficiency of the steel strand arrangement and tensioning schemes and enhancing the reliability of the tank structure.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a method for feasibility verification of steel strand arrangement and tensioning scheme in high-level water tanks, comprising the following steps:

[0006] S1: Develop a plan for the arrangement and tensioning of steel strands in the high-level water tank;

[0007] S2: Simplify the high-level water tank model and use the annular prestressing mechanism to calculate the vertical stress distribution on the inner wall of the prestressed concrete tank during the tensioning process of the steel strands;

[0008] S3: The tensioning process of the steel strands was numerically simulated using finite element software to obtain the vertical stress distribution on the inner wall of the prestressed concrete pool.

[0009] S4: Based on the results of theoretical calculations and numerical simulations, determine the feasibility of the steel strand arrangement and tensioning scheme.

[0010] The specific arrangement scheme of the steel strands in the high-level water tank in step S1 is as follows:

[0011] The elevated water tank includes a prestressed concrete tank body above ground and a regular reinforced concrete tank body below ground. The wall thickness of the prestressed concrete tank body is less than that of the regular reinforced concrete tank body, and there is a sudden change in cross-section between the two. The steel strands are slow-bonded prestressed steel strands. Each steel strand is arranged in a ring along the circumference of the prestressed concrete tank body. Several steel strands are evenly arranged vertically inside the prestressed concrete tank body. All steel strands are tensioned and anchored by four vertically arranged buttress columns set on the outer surface of the prestressed concrete tank body. The four buttress columns are located at 0°, 90°, 180° and 270° on the outer circle of the prestressed concrete tank body, respectively.

[0012] In step S1, the steel strand arrangement scheme is to determine the number of steel wires in each ring of steel strands and the vertical spacing between adjacent rings of steel strands; the number of steel wires in each ring of steel strands is 3 or 5 in the upper and lower rings, and the vertical spacing between adjacent rings of steel strands is not less than 150mm and not more than 3 times the wall thickness or 1m.

[0013] In step S1, the tensioning scheme for the steel strands involves tensioning the prestressed steel strands to 100% tension control force in one go or in stages according to a specific sequence.

[0014] The simplified model of the elevated water tank in step S2 is as follows: The elevated water tank is simplified into a vertically arranged prestressed concrete pipe, hereinafter referred to as the pipe. The height, diameter and wall thickness of the pipe are the same as those of the prestressed concrete tank.

[0015] The specific process of calculating the vertical tensile stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands in step S2 is as follows:

[0016] Through formula Calculate the radial pressure F per unit length along the circumference generated by tensioning the steel strand. zl A y σ is the cross-sectional area of ​​the prestressed steel strand per unit length of the duct; pe denoted as the effective prestress of the prestressed steel strand; r is the calculated radius of the pipe, which is the inner diameter of the pipe plus half the wall thickness of the pipe.

[0017] Through formula Calculate the elastic characteristic value S of the pipeline, where h is the pipeline wall thickness and μ is Poisson's ratio, which is taken as 1 / 6 for concrete.

[0018] Compare the distance x from the cross-section where the prestressed steel strand is applied to the two ends of the pipe with πS to determine the pipe type:

[0019] (1) Infinitely long pipe: The distance between the section where the prestressed steel strand is located and both ends of the pipe is greater than πS;

[0020] (2) Semi-infinite length pipe: The distance between the section where the prestressed steel strand is located and one end of the pipe is less than πS, and the distance between the section and the other end of the pipe is greater than πS;

[0021] (3) Finite-length pipe: The distance between the section where the prestressed steel strand is located and both ends of the pipe is less than πS;

[0022] The type of pipe is determined by the position of the prestressed steel strands, and each ring of steel strands must be judged.

[0023] Different types of pipes have different formulas for calculating the axial tensile stress on the inner surface of the pipe under single-ring prestressing:

[0024] (1) Infinitely long pipe:

[0025] (2) Semi-infinite pipe:

[0026] (3) Finite-length pipes:

[0027] in C a D a C when x = a x D x The value;

[0028] C |a-x| When x = |ax|, C x The value;

[0029]

[0030] Let F be the bending moment coefficient of a finite-length prestressed concrete pressure duct; L be the duct length; and a and b be F, respectively. zl The length of the point of application from the closer and farther ends of the pipe;

[0031] Different types of pipes use different methods for selecting the coordinate origin:

[0032] (1) Infinitely long pipe: The origin of the coordinate system is F zl Point of application;

[0033] (2) Semi-infinite pipe: The origin of the coordinate system is a distance F zl The end of the pipe closer to the point of action;

[0034] (3) Finite-length pipe: The origin of the coordinate system is at a distance F zl The end of the pipe closer to the point of action;

[0035] The formula for calculating the axial tensile stress on the inner surface of a pipe under the action of a single ring of prestressed steel strand is as follows: positive values ​​are tensile stress and negative values ​​are compressive stress. The axial tensile stress calculated for each ring of prestressed steel strand is multiplied by the tensioning coefficient k according to the established tensioning scheme, where k≤1.

[0036] The specific formula for calculating the axial tensile stress on the inner surface of the pipe under the action of a single ring prestressed steel strand is as follows: by transforming x in the formula, the axial tensile stress on the entire inner surface of the pipe under the action of a single ring prestressed steel strand is obtained; according to the established steel strand tensioning scheme, the axial tensile stress on the inner surface of the concrete pipe after tensioning each ring of steel strand is calculated sequentially, and the axial stress distribution on the inner surface of the pipe after each tensioning step is obtained by superimposing them sequentially.

[0037] The axial stress distribution on the inner surface of the pipe after each step of prestressed steel strand tensioning is as follows: The axial stress distribution obtained by superposition calculation does not consider the influence of gravity, and is obtained through the formula σ′ x,inner =σ x,inner -ρgc calculates the axial stress distribution on the inner surface of the pipe considering the influence of gravity, where c is F zl The distance from the point of application to the top of the pipe;

[0038] The specific formula for calculating the axial stress distribution on the inner surface of the pipe considering the influence of gravity is as follows: the influence of gravity is considered only after all superposition calculations are completed, and it does not participate in the superposition calculations; the part corresponding to the simplified model and the prestressed concrete pool is taken out, which is the theoretical calculation result of the vertical stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands.

[0039] Step S3 specifically involves: according to the steel strand arrangement and tensioning scheme, using finite element software to establish a high-level water tank model after each tensioning step, and calculating the numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete tank during the steel strand tensioning process.

[0040] Step S4 specifically involves the following: The theoretical calculation and numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands in the high-level water tank have a high degree of agreement. The difference lies in the fact that the numerical simulation results show a larger vertical compressive stress near the connection between the prestressed concrete pool and the ordinary reinforced concrete pool. Combining the theoretical calculation and numerical simulation results, the maximum vertical tensile stress on the inner wall of the prestressed concrete pool should meet the crack resistance condition.

[0041] The crack resistance condition is: σ x,in,max ≤1.2α ct γf tk , where α ct γ is the tensile stress limitation coefficient for concrete, with a value of 0.70; γ is the plasticity influence coefficient of concrete in the tension zone, with a value of 1.55; f tk This is the standard value for the tensile strength of concrete.

[0042] If the maximum vertical tensile stress on the inner wall of the prestressed concrete pool does not meet the crack resistance requirements, the steel strand arrangement and tensioning scheme should be reconfigured, and the feasibility of the scheme should be verified again.

[0043] The beneficial effects of this invention using the above technical solution are as follows: This invention provides a feasibility verification method for the arrangement and tensioning scheme of steel strands in elevated water tanks. Through theoretical calculations based on the annular prestressing mechanism and finite element numerical simulations, the axial stress distribution on the inner wall of the prestressed tank body considering the influence of gravity during the steel strand tensioning process is obtained, and the results closely match actual conditions. The combined results of theoretical calculations and numerical simulations verify the feasibility of the steel strand arrangement and tensioning scheme for elevated water tanks, demonstrating high reliability. This invention provides a theoretical basis and feasibility verification method for the design stage of steel strand arrangement and tensioning schemes in elevated water tanks, improving design efficiency, avoiding annular cracks on the inner surface of the prestressed lining during steel strand tensioning, and enhancing structural reliability. Attached Figure Description

[0044] Figure 1 This is a flowchart of the implementation steps of the present invention.

[0045] Figure 2 This is a cross-sectional schematic diagram of the elevated water tank in this invention.

[0046] Figure 3 This is a three-dimensional schematic diagram of the elevated water tank in this invention.

[0047] Figure 4 This is a three-dimensional schematic diagram of the prestressed steel strand in this invention.

[0048] Figure 5 This is a simplified schematic diagram of the elevated water tank in this invention.

[0049] Figure 6 This is a flowchart illustrating the vertical stress distribution on the inner wall of a prestressed concrete pool, obtained using the circumferential prestressing mechanism of the present invention. Detailed Implementation

[0050] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0051] like Figure 1 As shown, the feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to the present invention includes the following steps:

[0052] S1: Develop a plan for the arrangement and tensioning of steel strands in the high-level water tank;

[0053] S2: Simplify the high-level water tank model and use the annular prestressing mechanism to calculate the vertical stress distribution on the inner wall of the prestressed concrete tank during the tensioning process of the steel strands;

[0054] S3: The tensioning process of the steel strands was numerically simulated using finite element software to obtain the vertical stress distribution on the inner wall of the prestressed concrete pool.

[0055] S4: Based on the results of theoretical calculations and numerical simulations, determine the feasibility of the steel strand arrangement and tensioning scheme.

[0056] The specific arrangement scheme of the steel strands in the high-level water tank in step S1 is as follows:

[0057] like Figure 2-4 As shown, the elevated water tank includes a prestressed concrete tank 1 set above ground and a conventional reinforced concrete tank 2 set below ground. The wall thickness of the prestressed concrete tank 1 is less than that of the conventional reinforced concrete tank 2, and there is a sudden change in cross-section between the prestressed concrete tank 1 and the conventional reinforced concrete tank 2. The steel strands 3 are slow-bonded prestressed steel strands. Each steel strand 3 is arranged in a circular ring along the circumference of the prestressed concrete tank 1. Several steel strands 3 are evenly arranged vertically inside the prestressed concrete tank 1. All steel strands 3 are tensioned and anchored by four vertically arranged buttress columns 4 set on the outer surface of the prestressed concrete tank 1. The four buttress columns 4 are located at 0°, 90°, 180° and 270° on the outer circle of the prestressed concrete tank 1, respectively.

[0058] In step S1, the arrangement of steel strands 3 is to determine the number of steel wires in each ring of steel strands 3 and the vertical spacing between two adjacent rings of steel strands 3; the number of steel wires in each ring of steel strands 3 is 3 or 5 in the upper and lower rings, and the vertical spacing between two adjacent rings of steel strands 3 is not less than 150mm and not more than 3 times the wall thickness or 1m.

[0059] In step S1, the tensioning scheme for the prestressed steel strand 3 is to tension the prestressed steel strand 3 to 100% tension control force in one go or in stages according to a specific sequence.

[0060] like Figure 5 As shown, the simplified model of the elevated water tank in step S2 is as follows: The elevated water tank is simplified into a vertically arranged prestressed concrete pipe, hereinafter referred to as pipe 5. Pipe 5 has the same height, diameter and wall thickness as the prestressed concrete tank body 1.

[0061] like Figure 6 As shown, the specific process of calculating the vertical tensile stress distribution on the inner wall of the prestressed concrete pool 1 during the tensioning process of the steel strand 3 using the circumferential prestressing mechanism in step S2 is as follows:

[0062] Through formula Calculate the radial pressure F per unit length along the circumference generated by the tensioning of the steel strand. zl A y σ is the cross-sectional area of ​​the prestressed steel strand 3 per unit length of pipe 5; pe3 represents the effective prestress of the prestressed steel strand 3; r represents the calculated radius of the pipe 5, which is the inner diameter of the pipe 5 plus half the wall thickness of the pipe 5.

[0063] Through formula Calculate the elastic characteristic value S of pipe 5, where h is the wall thickness of pipe 5; μ is Poisson's ratio, which is taken as 1 / 6 for concrete;

[0064] Compare the distance x from the cross-section where the prestressed steel strand 3 is applied to both ends of the pipe 5 with πS to determine the type of pipe 5:

[0065] (1) Infinitely long pipe: The distance between the section where the prestressed steel strand 3 is located and both ends of the pipe 5 is greater than πS;

[0066] (2) Semi-infinite length pipe: The distance between the section where the prestressed steel strand 3 is located and one end of the pipe 5 is less than πS, and the distance between the section and the other end of the pipe 5 is greater than πS;

[0067] (3) Finite-length pipe: The distance between the section where the prestressed steel strand 3 is located and both ends of the pipe 5 is less than πS;

[0068] The type of pipe 5 is determined by the position of the prestressed steel strand 3, and each ring of steel strand 3 must be judged.

[0069] Different types of pipes 5 have different formulas for calculating the axial tensile stress on the inner surface of pipe 5 under single-ring prestressing:

[0070] (1) Infinitely long pipe:

[0071] (2) Semi-infinite pipe:

[0072] (3) Finite-length pipes:

[0073] in C a D a C when x = a x D x The value;

[0074] C| a-x When |x=|ax|, C x The value;

[0075]

[0076] Let F be the bending moment coefficient of the finite-length prestressed concrete pressure duct 5; L be the length of duct 5; and a and b be F, respectively. zl The length of the point of action from the closer and farther ends of pipe 5;

[0077] The method for selecting the origin of the 5-axis differs for different types of pipes:

[0078] (1) Infinitely long pipe: The origin of the coordinate system is F zl Point of application;

[0079] (2) Semi-infinite pipe: The origin of the coordinate system is a distance F zl One end of pipe 5, which is closer to the point of action;

[0080] (3) Finite-length pipe: The origin of the coordinate system is at a distance F zl One end of pipe 5, which is closer to the point of action;

[0081] The formula for calculating the axial tensile stress on the inner surface of the pipe 5 under the action of a single ring of prestressed steel strand 3 is as follows: positive values ​​are tensile stress and negative values ​​are compressive stress. The axial tensile stress calculated by tensioning each ring of prestressed steel strand 3 is multiplied by the tensioning coefficient k according to the established tensioning scheme, where k≤1.

[0082] The specific formula for calculating the axial tensile stress on the inner surface of the pipe 5 under the action of a single ring prestressed steel strand 3 is as follows: by transforming x in the formula, the axial tensile stress on the inner surface of the entire pipe 5 under the action of a single ring prestressed steel strand 3 is obtained; according to the established tensioning scheme of the steel strand 3, the axial tensile stress on the inner surface of the concrete pipe 5 after tensioning each ring of steel strand 3 is calculated sequentially, and the axial stress distribution on the inner surface of the pipe 5 after each tensioning step is obtained by superimposing them sequentially.

[0083] The axial stress distribution on the inner surface of pipe 5 after each step of prestressed steel strand tensioning is as follows: The axial stress distribution obtained by superposition calculation does not consider the influence of gravity, and is obtained through the formula σ′ x,inner =σ x,inner -ρgc calculates the axial stress distribution on the inner surface of pipe 5 considering the influence of gravity, where c is F zl The distance from the point of application to the top of pipe 5;

[0084] The specific formula for calculating the axial stress distribution on the inner surface of pipe 5 considering the influence of gravity is as follows: the influence of gravity is considered only after all superposition calculations are completed, and it does not participate in the superposition calculation; the part corresponding to the simplified model and the prestressed concrete pool 1 is taken out, which is the theoretical calculation result of the vertical stress distribution on the inner wall of the prestressed concrete pool 1 during the tensioning process of the steel strand 3.

[0085] Step S3 specifically involves: according to the arrangement and tensioning scheme of the steel strands 3, using finite element software to establish a high-level water tank model after each tensioning step, and calculating the numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete pool 1 during the tensioning process of the steel strands 3.

[0086] Step S4 specifically involves the following: The theoretical calculation and numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete pool 1 during the tensioning process of the steel strand 3 in the high-level water tank show a high degree of agreement. The difference lies in the fact that the numerical simulation results show a larger vertical compressive stress near the connection between the prestressed concrete pool 1 and the ordinary reinforced concrete pool 2. Combining the theoretical calculation and numerical simulation results, the maximum vertical tensile stress on the inner wall of the prestressed concrete pool 1 should meet the crack resistance condition.

[0087] The crack resistance condition is: σ x,in,max ≤1.2α ct γf tk , where α ct γ is the tensile stress limitation coefficient for concrete, with a value of 0.70; γ is the plasticity influence coefficient of concrete in the tension zone, with a value of 1.55; f tk This is the standard value for the tensile strength of concrete.

[0088] If the maximum vertical tensile stress on the inner wall of the prestressed concrete pool 1 does not meet the crack resistance requirements, the arrangement and tensioning scheme of the steel strands 3 should be reconfigured, and the feasibility of the scheme should be verified again.

[0089] The above embodiments illustrate the basic principles and features of the present invention, but are merely preferred embodiments and are not limited to these embodiments. Those skilled in the art, inspired by this patent, can make many modifications and improvements without departing from the spirit and scope of the claims, all of which fall within the scope of protection of the present invention. Therefore, the scope of this patent and its protection should be determined by the appended claims.

Claims

1. A method for verifying the feasibility of steel strand arrangement and tensioning scheme in a high-level water tank, characterized in that: Includes the following steps: S1: Develop a plan for the arrangement and tensioning of steel strands in the high-level water tank; S2: Simplify the high-level water tank model and use the annular prestressing mechanism to calculate the vertical stress distribution on the inner wall of the prestressed concrete tank during the tensioning process of the steel strands; S3: The tensioning process of the steel strands was numerically simulated using finite element software to obtain the vertical stress distribution on the inner wall of the prestressed concrete pool. S4: Based on the results of theoretical calculations and numerical simulations, determine the feasibility of the steel strand arrangement and tensioning scheme.

2. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 1, characterized in that: The specific arrangement scheme of the steel strands in the high-level water tank in step S1 is as follows: The elevated water tank includes a prestressed concrete tank body above ground and a regular reinforced concrete tank body below ground. The wall thickness of the prestressed concrete tank body is less than that of the regular reinforced concrete tank body, and there is a sudden change in cross-section between the two. The steel strands are slow-bonded prestressed steel strands. Each steel strand is arranged in a ring along the circumference of the prestressed concrete tank body. Several steel strands are evenly arranged vertically inside the prestressed concrete tank body. All steel strands are tensioned and anchored by four vertically arranged buttress columns set on the outer surface of the prestressed concrete tank body. The four buttress columns are located at 0°, 90°, 180° and 270° on the outer circle of the prestressed concrete tank body, respectively.

3. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 2, characterized in that: In step S1, the steel strand arrangement scheme is to determine the number of steel wires in each ring of steel strands and the vertical spacing between adjacent rings of steel strands; the number of steel wires in each ring of steel strands is 3 or 5 in the upper and lower rings, and the vertical spacing between adjacent rings of steel strands is not less than 150mm and not more than 3 times the wall thickness or 1m.

4. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 3, characterized in that: In step S1, the tensioning scheme for the steel strands involves tensioning the prestressed steel strands to 100% tension control force in one go or in stages according to a specific sequence.

5. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 4, characterized in that: The simplified model of the elevated water tank in step S2 is as follows: The elevated water tank is simplified into a vertically arranged prestressed concrete pipe, hereinafter referred to as the pipe. The height, diameter and wall thickness of the pipe are the same as those of the prestressed concrete tank.

6. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 5, characterized in that: The specific process of calculating the vertical tensile stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands in step S2 is as follows: Through formula Calculate the radial pressure F per unit length along the circumference generated by tensioning the steel strand. zl A y σ is the cross-sectional area of ​​the prestressed steel strand per unit length of the duct; pe denoted as the effective prestress of the prestressed steel strand; r is the calculated radius of the pipe, which is the inner diameter of the pipe plus half the wall thickness of the pipe. Through formula Calculate the elastic characteristic value S of the pipeline, where h is the pipeline wall thickness and μ is Poisson's ratio, which is taken as 1 / 6 for concrete. Compare the distance x from the cross-section where the prestressed steel strand is applied to the two ends of the pipe with πS to determine the pipe type: (1) Infinitely long pipe: The distance between the section where the prestressed steel strand is located and both ends of the pipe is greater than πS; (2) Semi-infinite length pipe: The distance between the section where the prestressed steel strand is located and one end of the pipe is less than πS, and the distance between the section and the other end of the pipe is greater than πS; (3) Finite-length pipe: The distance between the section where the prestressed steel strand is located and both ends of the pipe is less than πS; The type of pipe is determined by the position of the prestressed steel strands, and each ring of steel strands must be judged. Different types of pipes have different formulas for calculating the axial tensile stress on the inner surface of the pipe under single-ring prestressing: (1) Infinitely long pipe: (2) Semi-infinite pipe: (3) Finite-length pipes: in C a D a C when x = a x D x The value; C |a-x| When x = |ax|, C x The value; Let F be the bending moment coefficient of a finite-length prestressed concrete pressure duct; L be the duct length; and a and b be F, respectively. zl The length of the point of application from the closer and farther ends of the pipe; Different types of pipes use different methods for selecting the coordinate origin: (1) Infinitely long pipe: The origin of the coordinate system is F zl Point of application; (2) Semi-infinite pipe: The origin of the coordinate system is a distance F zl The end of the pipe closer to the point of action; (3) Finite-length pipe: The origin of the coordinate system is at a distance F zl The end of the pipe closer to the point of action; The formula for calculating the axial tensile stress on the inner surface of a pipe under the action of a single-ring prestressed steel strand is given. Positive values ​​are tensile stresses and negative values ​​are compressive stresses. The axial tensile stress obtained from the tensioning calculation of each ring of prestressed steel strand is multiplied by the tensioning coefficient k, k≤1, according to the established tensioning scheme; The specific formula for calculating the axial tensile stress on the inner surface of the pipe under the action of a single ring prestressed steel strand is as follows: by transforming x in the formula, the axial tensile stress on the entire inner surface of the pipe under the action of a single ring prestressed steel strand is obtained; according to the established steel strand tensioning scheme, the axial tensile stress on the inner surface of the concrete pipe after tensioning each ring of steel strand is calculated sequentially, and the axial stress distribution on the inner surface of the pipe after each tensioning step is obtained by superimposing them sequentially. The axial stress distribution on the inner surface of the pipe after each step of prestressed steel strand tensioning is as follows: The axial stress distribution obtained by superposition calculation does not consider the influence of gravity, and is obtained through the formula σ′ x,inner =σ x,inner -ρgc calculates the axial stress distribution on the inner surface of the pipe considering the influence of gravity, where c is F zl The distance from the point of application to the top of the pipe; The specific formula for calculating the axial stress distribution on the inner surface of the pipe considering the influence of gravity is as follows: the influence of gravity is considered only after all superposition calculations are completed, and it does not participate in the superposition calculations; the part corresponding to the simplified model and the prestressed concrete pool is taken out, which is the theoretical calculation result of the vertical stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands.

7. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 6, characterized in that: Step S3 specifically involves: according to the steel strand arrangement and tensioning scheme, using finite element software to establish a high-level water tank model after each tensioning step, and calculating the numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete tank during the steel strand tensioning process.

8. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 7, characterized in that: Step S4 specifically involves the following: The theoretical calculation and numerical simulation results of the vertical stress distribution on the inner wall of the prestressed concrete pool during the tensioning process of the steel strands in the high-level water tank have a high degree of agreement. The difference lies in the fact that the numerical simulation results show a larger vertical compressive stress near the connection between the prestressed concrete pool and the ordinary reinforced concrete pool. Combining the theoretical calculation and numerical simulation results, the maximum vertical tensile stress on the inner wall of the prestressed concrete pool should meet the crack resistance condition. The crack resistance condition is: σ x,in,max ≤1.2α ct γf tk , where α ct γ is the tensile stress limitation coefficient for concrete, with a value of 0.70; γ is the plasticity influence coefficient of concrete in the tension zone, with a value of 1.55; f tk This is the standard value for the tensile strength of concrete.

9. The feasibility verification method for the arrangement and tensioning scheme of steel strands in a high-level water tank according to claim 8, characterized in that: If the maximum vertical tensile stress on the inner wall of the prestressed concrete pool does not meet the crack resistance requirements, the steel strand arrangement and tensioning scheme should be reconfigured, and the feasibility of the scheme should be verified again.

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