A high-strength cold-cast anchor structure dimension parameterization analysis method

Abstract

This invention discloses a parameterized analysis method for the structural dimensions of a high-strength cold-cast anchor, comprising the following steps: S1, determining the strength and diameter of the parallel steel wire according to actual requirements; S2, calculating the minimum cone length of the anchor cup to obtain the selection range of the anchor cup cone length, and initially selecting the anchor cup cone length; S3, selecting the inner diameter and cone angle of the rear cone of the anchor cup, and calculating the inner diameter of the front cone; S4, calculating the circumferential surface area of ​​the cone of the cold-cast filler; S5, calculating the compressive stress of the cone of the cold-cast filler; S6, determining σ... c Is it less than [σ]? c If yes, proceed to step S7; otherwise, remove any one of the currently selected anchor cup cone length, rear end cone inner diameter, or cone angle from the selection range, and proceed to step S2; S7: Select the anchor cup outer diameter, calculate the anchor cup average inner diameter and anchor cup circumferential stress; S8: Determine σ r Is it less than [σ]? r If yes, proceed to step S10; otherwise, proceed to step S9; S9: Adjust the outer diameter of the anchor cup and proceed to step S7; S10: Complete the dimensional analysis of the high-strength cold-cast structure.

Description

Technical Field

[0001] This invention relates to the field of bridges, and in particular to a method for parameterized analysis of the dimensions of high-strength cold-cast anchor structures. Background Technology

[0002] High-strength cold-cast anchorages are widely used in arch bridge cables, cable-stayed bridge cables, and suspension bridge cables. In recent years, the application of cold-cast anchorages for various types of bridges, including highway and railway bridges, has been increasing. When designing cold-cast anchorages, if the diameter of the steel wire to be used changes, the strength increases, or the specifications expand, existing design dimensions are often referenced and adjusted. The design is then completed primarily through experimental testing, supplemented by finite element analysis. However, there is a lack of effective methods and technical approaches to analyze the impact of changes in the structural dimensions of various parts on the stress of the anchorage.

[0003] The existing technical means do not have a systematic method for parametric analysis of the structure dimensions of high-strength cold-cast anchors. As a result, the existing parameter analysis is basically based on selecting values ​​according to requirements and then performing calculations. It has a large degree of randomness and lacks a systematic approach to simultaneously satisfying the above four conditions, which increases the difficulty of parameter analysis and reduces efficiency.

[0004] A parameterized analysis method for the structural dimensions of high-strength cold-cast anchors is needed to solve the above problems. Summary of the Invention

[0005] This invention addresses the problem in existing technologies where, when adapting to changes in the diameter, strength, or specifications of the steel wire, adjustments are often made based on existing design dimensions, followed by experimental testing and supplementary finite element analysis. However, there is a lack of effective methods and technical approaches for analyzing the impact of changes in structural dimensions on the stress of the anchorage. This invention provides a parametric analysis method for the structural dimensions of high-strength cold-cast anchors, offering a systematic approach to parametric analysis of the structural dimensions of high-strength cold-cast anchors, thus solving the aforementioned problems.

[0006] This invention provides a method for parameterized analysis of the dimensions of high-strength cold-cast anchor structures, comprising the following steps: S1. Determine the strength of the parallel steel wires according to actual needs. s b and wire diameter d ; S2. Calculate the minimum cone length of the anchor cup. L 1min， The range for selecting the anchor cup cone length is obtained, and the anchor cup cone length is initially selected within the range that is greater than or equal to the minimum cone length of the anchor cup. L 1 ; S3. Preliminary selection of the inner diameter of the rear cone of the anchor cup. D 0and cone angle β And thus calculate the inner diameter of the front cone. D 1 ; S4. Calculate the circumferential surface area of ​​the cone-shaped cold-cast filler. A e ; S5. Calculate the compressive stress of the cold-cast packing cone. s c ; S6, Judgment s c Is it less than the allowable compressive stress value of the cold-cast filler cone? s c If yes, proceed to step S7; otherwise, change the length of the currently selected anchor cup cone. L 1 The inner diameter of the cone at the rear end of the anchor cup D 0 or cone angle β Remove any one of the selected items from the selection range and proceed to step S2; S7. Preliminary selection of average outer diameter of anchor cup D i Calculate the average inner diameter of the anchor cup D j Then, the circumferential stress of the anchor cup is calculated. s r ; S8, Judgment s r Is it less than the allowable value of circumferential stress of the anchor cup? s r If yes, proceed to step S10; otherwise, proceed to step S9. S9. Adjust the average outer diameter of the anchor cup. D i Take the value and proceed to step S7; S10. Complete the dimensional analysis of the high-strength cold-cast structure.

[0007] The present invention provides a method for parameterizing the structural dimensions of a high-strength cold-cast anchor. As a preferred embodiment, step S2 calculates the minimum cone length of the anchor cup. L 1min， The specific method is as follows: Calculate the bonding stress of cold-cast filler to steel wire t b The specific formula is as follows: ; in, t b This is the calculated value of the bond stress between the steel wire and the cold-cast filler; t b [This refers to the allowable bonding stress between the steel wire and the cold-cast filler.]d The diameter of the steel wire; s b The nominal tensile strength of the steel wire; K This is the effective anchorage length coefficient; L 1 The length of the cone in the anchor cup; To ensure that the bonding stress between the steel wire and the cold-cast filler is less than the allowable value, the following is obtained. L 1 The minimum value is the minimum cone length. L 1min .

[0008] The present invention provides a method for parametric analysis of the dimensions of a high-strength cold-cast anchor structure. As a preferred embodiment, step S3 involves calculating the inner diameter of the front cone. D 1 The specific formula is: D 1 = D 0 -2 β × L 1 , in, D 0 This refers to the inner diameter of the rear cone. β It is the cone angle; L 1 The length of the cone in the anchor cup.

[0009] The present invention provides a method for parameterizing the dimensions of a high-strength cold-cast anchor structure. As a preferred method, the circumferential surface area of ​​the cone-shaped cold-cast filler is obtained. A e The specific calculation method is as follows: A e =0.5×π×( D 0 + D 1 )× L 1 , in, D 0 This refers to the inner diameter of the rear cone. D 1 The inner diameter of the front cone; L 1 The length of the cone in the anchor cup.

[0010] The present invention provides a method for parameterizing the dimensions of a high-strength cold-cast anchor structure. As a preferred embodiment, in step S5, the compressive stress of the cold-cast filler cone is... s c The specific calculation method is as follows: ; in, s c The calculated value of the compressive stress of the cold-cast filler cone; s c [This refers to the allowable compressive stress value of the cold-cast filler cone;] P b The nominal breaking load of the cable wire bundle; A e The circumferential surface area of ​​the cold-cast filler cone; i The friction angle between the cold-cast filler and the inner conical surface of the anchor cup; β The cone angle of the anchor cup.

[0011] The present invention provides a method for parametric analysis of the structural dimensions of a high-strength cold-cast anchor. As a preferred embodiment, the average inner diameter of the anchor cup in step S7 is... D j， The specific calculation method is as follows: D j = ( D 0 + D 1 )÷2, in, D 0 This refers to the inner diameter of the rear cone. D 1 This is the inner diameter of the front cone.

[0012] The present invention provides a method for parameterizing the structural dimensions of a high-strength cold-cast anchor. As a preferred embodiment, step S7 involves the circumferential stress of the anchor cup. s r The specific calculation method is as follows: ; in, s r The calculated value of the circumferential stress of the anchor cup; s r [This refers to the allowable circumferential stress value of the anchor cup;] s c This refers to the calculated compressive stress value of the cold-cast filler cone. D i The average outer diameter of the anchor cup; D j This represents the average inner diameter of the anchor cup.

[0013] The present invention provides a method for parameterizing the dimensions of a high-strength cold-cast anchor structure. In a preferred embodiment, step S1 can be based on the actual needs of the bridge cable stress or on the analysis requirements in the study of the influence of variable parameters.

[0014] The structural dimensions of anchorages are typically determined by the following factors: the anchorage length within the anchor cup, which must meet the bonding strength requirements between the cold-cast anchorage filler and the wire, and should be greater than the minimum strand length required for pull-out testing of the wire in the cold-cast filler; the compressive stress of the cone within the anchor cup, which must be less than the allowable compressive strength of the cold-cast filler to prevent cone failure; the angle between the generatrix of the cone surface within the anchor cup and the axis (anchor cup cone angle), which, if too small, can easily cause excessive shrinkage of the casting after top pressure; and the average wall thickness of the anchor cup, which must meet the circumferential stress generated on the anchor cup wall by the pressure caused by the casting.

[0015] The beneficial effects of this invention are as follows: This method ensures that the anchoring length of the steel wire inside the anchor cup meets the bonding strength requirements between the cold-cast anchor filler and the steel wire; the compressive stress of the cone in the anchor cup is less than the allowable compressive strength of the cold-cast filler; the angle between the generatrix of the cone surface inside the anchor cup and the axis is sufficient; and the average wall thickness of the anchor cup satisfies the circumferential stress generated on the anchor cup wall by the pressure caused by the casting. This allows us to obtain the inner diameter of the rear cone; the cone length; the cone angle; the inner diameter of the front cone; the outer diameter of the anchor cup; and the average inner diameter of the anchor cup. Furthermore, this invention meets various cable conditions and has strong versatility. Attached Figure Description

[0016] Figure 1 This is a flowchart of a method for parameterizing the dimensions of a high-strength cold-cast anchor structure. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Example 1

[0018] like Figure 1 As shown, a method for parameterizing the dimensions of a high-strength cold-cast anchor structure includes the following steps: Includes the following steps: S1. Determine the strength of the parallel steel wires according to actual needs. s b and wire diameter d ; S2. Calculate the minimum cone length of the anchor cup. L 1min， The range for selecting the anchor cup cone length is obtained, and the anchor cup cone length is initially selected within the range that is greater than or equal to the minimum cone length of the anchor cup. L 1 ; S3. Preliminary selection of the inner diameter of the rear cone of the anchor cup. D 0 and cone angle βAnd thus calculate the inner diameter of the front cone. D 1 ; S4. Calculate the circumferential surface area of ​​the cone-shaped cold-cast filler. A e ; S5. Calculate the compressive stress of the cold-cast packing cone. s c ; S6, Judgment s c Is it less than the allowable compressive stress value of the cold-cast filler cone? s c If yes, proceed to step S7; otherwise, change the length of the currently selected anchor cup cone. L 1 The inner diameter of the cone at the rear end of the anchor cup D 0 or cone angle β Remove any one of the selected items from the selection range and proceed to step S2; S7. Preliminary selection of average outer diameter of anchor cup D i Calculate the average inner diameter of the anchor cup D j， Then, the circumferential stress of the anchor cup is calculated. s r ; S8, Judgment s r Is it less than the allowable value of circumferential stress of the anchor cup? s r If yes, proceed to step S10; otherwise, proceed to step S9. S9. Adjust the average outer diameter of the anchor cup. D i Take the value and proceed to step S7; S10. Complete the dimensional analysis of the high-strength cold-cast structure.

[0019] Step S2: Calculate the minimum cone length of the anchor cup. L 1min， The specific method is as follows: Calculate the bonding stress of cold-cast filler to steel wire t b The specific formula is as follows: ; in, t b This is the calculated value of the bond stress between the steel wire and the cold-cast filler; t b [This refers to the allowable bonding stress between the steel wire and the cold-cast filler, typically 25 MPa.] d The diameter of the steel wire is 7mm in this design; sb The nominal tensile strength of the steel wire; K The effective anchorage length factor, considering that the steel wire at the anchorage position cannot be fully bonded, is generally 2 / 3; L 1 The length of the cone in the anchor cup; To ensure that the bonding stress between the steel wire and the cold-cast filler is less than the allowable value, the following is obtained. L 1 The minimum value is the minimum cone length. L 1min .

[0020] In step S3, calculate the inner diameter of the front cone. D 1 The specific formula is: D 1 = D 0 -2 β × L 1 , in, D 0 This refers to the inner diameter of the rear cone. β It is the cone angle; L 1 The length of the cone in the anchor cup.

[0021] Circumferential surface area of ​​the cone-shaped cold-cast filler A e The specific calculation method is as follows: A e =0.5×π×( D 0 + D 1 )× L 1 , in, D 0 This refers to the inner diameter of the rear cone. D 1 The inner diameter of the front cone; L 1 The length of the cone in the anchor cup.

[0022] The compressive stress of the cold-cast filler cone in step S5 s c The specific calculation method is as follows: ; in, s c The calculated value of the compressive stress of the cold-cast filler cone; s c[This refers to the allowable compressive stress value of the cold-cast filler cone; for a 2100MPa grade cable, 160MPa is used.] P b The nominal breaking load of the cable wire bundle; A e The circumferential surface area of ​​the cold-cast filler cone; i The friction angle between the cold-cast filler and the inner conical surface of the anchor cup is generally 24.22°, or 0.423 rad. β The cone angle of the anchor cup.

[0023] The average inner diameter of the anchor cup in step S7 D j， The specific calculation method is as follows: D j = ( D 0 + D 1 )÷2, in, D 0 This refers to the inner diameter of the rear cone. D 1 This is the inner diameter of the front cone.

[0024] Circumferential stress of the anchor cup in step S7 s r The specific calculation method is as follows: ; in, s r The calculated value of the circumferential stress of the anchor cup; s r [This refers to the allowable circumferential stress value of the anchor cup, which is determined according to the anchor cup material and national standards.] s c This refers to the calculated compressive stress value of the cold-cast filler cone. D i The average outer diameter of the anchor cup; D j This represents the average inner diameter of the anchor cup.

[0025] In step S1, the actual requirements can be based on the stress requirements of the bridge cables or, in the study of the influence of variable parameters, on the analytical needs.

[0026] This method can be used under various cable conditions and is universally applicable to different numbers of wires.

[0027] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor, characterized in that: Includes the following steps: S1. Determine the strength of the parallel steel wires according to actual needs. σ b and wire diameter d ; S2. Calculate the minimum cone length of the anchor cup. L 1min， The range for selecting the anchor cup cone length is obtained, and the anchor cup cone length is initially selected within the range that is greater than or equal to the minimum cone length of the anchor cup. L 1 ; S3. Preliminary selection of the inner diameter of the rear cone of the anchor cup. D 0 and cone angle β And thus calculate the inner diameter of the front cone. D 1 ; S4. Calculate the circumferential surface area of ​​the cone-shaped cold-cast filler. A e ; S5. Calculate the compressive stress of the cold-cast packing cone. σ c ; S6, Judgment σ c Is it less than the allowable compressive stress value of the cold-cast filler cone? σ c If yes, proceed to step S7; otherwise, change the length of the currently selected anchor cup cone. L 1 The inner diameter of the cone at the rear end of the anchor cup D 0 or cone angle β Remove any one of the selected items from the selection range and proceed to step S2; S7. Preliminary selection of average outer diameter of anchor cup D i Calculate the average inner diameter of the anchor cup D j Then, the circumferential stress of the anchor cup is calculated. σ r ; S8, Judgment σ r Is it less than the allowable value of circumferential stress of the anchor cup? σ r If so, proceed to step S10; Otherwise, proceed to step S9; S9. Adjust the average outer diameter of the anchor cup. D i Take the value and proceed to step S7; S10. Complete the dimensional analysis of the high-strength cold-cast structure; Step S2 calculates the minimum cone length of the anchor cup. L 1min， The specific method is as follows: Calculate the bonding stress of cold-cast filler to steel wire τ b The specific formula is as follows: ； in, τ b This is the calculated value of the bond stress between the steel wire and the cold-cast filler; τ b [This refers to the allowable bonding stress between the steel wire and the cold-cast filler.] d The diameter of the steel wire; σ b The nominal tensile strength of the steel wire; K This is the effective anchorage length coefficient; L 1 The length of the cone in the anchor cup; To ensure that the bonding stress between the steel wire and the cold-cast filler is less than the allowable value, the following is obtained. L 1 The minimum value is the minimum cone length. L 1min .

2. The method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor according to claim 1, characterized in that: The calculation of the inner diameter of the front cone in step S3 D 1 The specific formula is: D 1 = D 0 -2 β × L 1 ， in, D 0 This refers to the inner diameter of the rear cone. β It is the cone angle; L 1 The length of the cone in the anchor cup.

3. The method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor according to claim 1, characterized in that: The cone-shaped circumferential surface area of ​​the cold-cast filler A e The specific calculation method is as follows: A e =0.5×π×（ D 0 + D 1 ）× L 1 ， in, D 0 This refers to the inner diameter of the rear cone. D 1 The inner diameter of the front cone; L 1 The length of the cone in the anchor cup.

4. The method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor according to claim 1, characterized in that: The compressive stress of the cold-cast filler cone in step S5 σ c The specific calculation method is as follows: ； in, σ c The calculated value of the compressive stress of the cold-cast filler cone; σ c [This refers to the allowable compressive stress value of the cold-cast filler cone;] P b The nominal breaking load of the cable wire bundle; A e The circumferential surface area of ​​the cold-cast filler cone; θ The friction angle between the cold-cast filler and the inner conical surface of the anchor cup; β The cone angle of the anchor cup.

5. The method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor according to claim 1, characterized in that: The average inner diameter of the anchor cup mentioned in step S7 D j， The specific calculation method is as follows: D j =（ D 0 + D 1 ）÷2， in, D 0 This refers to the inner diameter of the rear cone. D 1 This is the inner diameter of the front cone.

6. The method for parameterized analysis of the structural dimensions of a high-strength cold-cast anchor according to claim 1, characterized in that: The circumferential stress of the anchor cup mentioned in step S7 σ r The specific calculation method is as follows: ； in, σ r The calculated value of the circumferential stress of the anchor cup; σ r [This refers to the allowable circumferential stress value of the anchor cup;] σ c This refers to the calculated compressive stress value of the cold-cast filler cone. D i The average outer diameter of the anchor cup; D j This represents the average inner diameter of the anchor cup.

Images