Method for adjusting length of main cable through cable system ground anchor backpack padding sleeper

Abstract

The invention provides a method for adjusting the length of a main cable by padding sleepers on a ground anchor backpack of a cable system, which comprises the following steps of: establishing a relational expression among the radius of the main ground anchor backpack, the thickness of the sleepers and a cable length adjusting value through analytic geometry, and adjusting the length of the main cable on the premise that the radius of the main ground anchor backpack and the cable length adjusting value are known. The accurate thickness value of the main ground anchor knapsack can be obtained according to the relational expression, in the sag adjusting process of the main cable, the cable adjusting can be completed through quick cushion plugging, repeated operation in the construction process is avoided, and then the construction efficiency can be improved.

Description

Technical Field

[0001] This invention relates to the field of cable hoisting system installation and construction technology, specifically to a method for adjusting the length of the main cable by inserting sleepers into the ground anchor backpack of a cable system. Background Technology

[0002] Cable-stayed hoisting systems consist of a main cable, tower, ground anchors, and guy wires. The main cable is the primary load-bearing component, responsible for the weight being lifted, and has always been a key focus in design and construction. For the wire rope, its sag during installation is a critical control indicator. In actual construction, the sag of the main cable must be repeatedly adjusted to ensure it remains within the design tolerance range before lifting operations can proceed; otherwise, the entire system will face significant safety hazards.

[0003] like Figure 1 As shown, the mid-span sag of the main cable in the installed state is represented by f. a The mid-span sag in the working state is represented by f. b This indicates that sag is a crucial parameter of the main cable alignment, directly determining the stress on the main cable under load. The main cable of the cable-stayed hoisting system is installed in the middle of the tower (indicated by the black line). When the cable-stayed hoisting system is performing hoisting operations, the main cable needs to be moved laterally to the working position (indicated by the red line). After the lateral movement is completed, f... a <f b In certain situations, the length of the main cable needs to be adjusted to reduce the mid-span sag error between the working state and the installation state.

[0004] like Figure 2 As shown, the method for adjusting the main cable length generally involves using sleeper shims to temporarily increase the radius of the anchorage backpack, thus increasing the length of the main cable wound around the backpack and decreasing the sag of the main cable in the mid-span. Adjusting the cable length is a relatively iterative and complex process. The thickness of the sleeper shims is usually provided by construction experience or obtained by comparing similar projects. This method is more suitable for bridges with smaller spans, but for large-span bridge systems, there are often few reference cases for the thickness of the shims. Furthermore, the shim thickness obtained from experience often deviates from the actual thickness, requiring temporary additions or removals of sleepers and multiple adjustments to obtain the appropriate cable length and mid-span sag, making the corresponding construction procedures complex and the cable length adjustment inefficient. In addition, because the radii of the anchorage backpacks vary, the empirical value of the shim thickness can only be used interchangeably between different projects. Summary of the Invention

[0005] To address the technical problems mentioned in the background section, this invention provides a method for adjusting the main cable length using ground anchor backpack padding sleepers in a cable system, which can improve the efficiency of main cable length adjustment.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for adjusting the length of the main cable in a cable system by inserting sleepers into the main anchor backpack of the cable system, thereby increasing the length of the main cable wound around the backpack and reducing the sag of the main cable in the middle span, includes the following steps:

[0008] S1. Through analytical geometry, establish the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value. Given that the backpack radius and cable length adjustment value are known, substitute the known main anchor backpack radius and cable length adjustment value into the established relationship to calculate the sleeper thickness.

[0009] S2, the main anchor of the cable system is padded with sleepers. The thickness of the sleepers padded is the same as the thickness of the sleepers calculated in step S1, so that the sag of the main cable in the middle span can be adjusted to the set value.

[0010] Furthermore, a rectangular coordinate system is established with the center of the sleeper of the padding as the origin, the x-axis as the horizontal line, and the y-axis as the vertical line; the center of the main anchor backpack is denoted as C2, and its coordinates are ( , The radius R of the main anchor backpack is a known quantity; the center of the sleeper is denoted as C1, with coordinates (0, 0), and the radius r is a quantity to be determined, where r is the thickness of the sleeper; let... and Let B be the common tangent between the main anchor backpack and the sleeper. The point of tangency with the sleeper, For the common tangent The point of tangency with the sleeper; C is the common tangent. The point of tangency with the main anchor backpack, C', is the common tangent. The point of tangency with the main anchor backpack; Let the horizontal angle between the lines connecting the centers of the main anchor backpack and the sleeper be the same as the angle of the main cable, and this is a known quantity; then the cable length adjustment value is... Calculate according to the following formula:

[0011] (1);

[0012] In the formula, The distance between tangent point C and tangent point B; tangent point The arc length between the point of tangency B; tangent point with tangent point The arc length between them.

[0013] Furthermore, The length is calculated using the following formula:

[0014] (2);

[0015] In the formula, ( () are the coordinates of the tangent point B; Let C be the coordinates of the tangent point C, where...

[0016] (3);

[0017] (4);

[0018] (5);

[0019] (6);

[0020] (7);

[0021] (8);

[0022] (9);

[0023] (10).

[0024] Furthermore, The length is calculated using the following formula:

[0025] (11);

[0026] In the formula, ( () is the tangent point The coordinates are calculated using the following formula:

[0027] (12);

[0028] (13);

[0029] .

[0030] Furthermore, The length is calculated using the following formula:

[0031] ;

[0032] In the formula, ( ( ) are the coordinates of the tangent point C; () is the tangent point The coordinates of, where,

[0033] ;

[0034] ;

[0035] ;

[0036] ;

[0037] ;

[0038] Substituting formulas (2)-(20) into formula (1) will establish the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value.

[0039] By adopting the above technical solution, the present invention has the following beneficial effects:

[0040] The method described above for adjusting the main cable length by inserting sleepers into the anchor backpack of the cable system establishes a relationship between the radius of the main anchor backpack, the thickness of the sleepers, and the adjustment value of the cable length through analytical geometry. Given that the radius of the main anchor backpack and the adjustment value of the cable length are known, the thickness value of the main anchor backpack can be obtained relatively accurately based on the relationship. During the adjustment of the main cable sag, the adjustment can be completed quickly by inserting sleepers, avoiding repeated operations during construction and thus improving construction efficiency. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the lateral movement process of the main cable in a cable system.

[0042] Figure 2 This is a schematic diagram of a backpack used as a ground anchor, with sleepers inserted as padding.

[0043] Figure 3 This is a flowchart illustrating a preferred embodiment of the present invention of a method for adjusting the length of the main cable using a cable system anchor backpack padding sleepers.

[0044] Figure 4 This is a mathematical model diagram of the ground anchor backpack padding sleeper in the method for adjusting the length of the main cable in a cable system according to a preferred embodiment of the present invention. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0048] Please also see Figure 1 and Figure 4 A preferred embodiment of the present invention provides a method for adjusting the length of the main cable in a cable system by inserting sleepers into the main anchor backpack of the cable system. This method uses sleepers to insert sleepers into the main anchor backpack, thereby increasing the length of the main cable wound around the backpack and reducing the sag of the mid-span main cable. The method includes the following steps:

[0049] S1. Using analytical geometry, establish the relationship between the main anchor backpack radius, sleeper thickness, and cable length adjustment value. Given the backpack radius and cable length adjustment value, substitute the known main anchor backpack radius and cable length adjustment value into the established relationship to calculate the sleeper thickness.

[0050] Specifically, please see Figure 4 , Figure 4 The blue arc represents the padding sleepers, and the black circle represents the main anchor backpack. Establish a rectangular coordinate system with the center C1 of the padding sleepers as the origin, with the x-axis as the horizontal line and the y-axis as the vertical line; denote the center of the main anchor backpack as C2, and its coordinates are (…). , The radius R of the main anchor backpack is a known quantity; the center of the sleeper is denoted as C1, with coordinates (0, 0), and the radius r is the thickness of the sleeper, which is a quantity to be determined; let... and Let B be the common tangent between the main anchor backpack and the sleeper. The point of tangency with the sleeper, For the common tangent The point of tangency with the sleeper; C is the common tangent. The point of tangency with the main anchor backpack, For the common tangent The point of tangency with the main anchor backpack; The horizontal angle between the line connecting the centers of the main anchor backpack and the sleeper is the same as the angle of the main cable and is a known quantity. (Common tangent) The angle between the line connecting the circle and the center is denoted as . Before the main cable adjustment, the original main cable was attached to the main anchor backpack at point C, and then... 1 after The main cable separates from the main anchor backpack at this point, therefore the contact length between the main cable and the main anchor backpack is... Arc length. When sleepers are added, the contact length becomes... + + The radius of the main anchor backpack was temporarily increased to adjust the length of the main cable. Cable length adjustment value. Calculate according to the following formula:

[0051] (1);

[0052] In the formula, The distance between tangent point C and tangent point B; tangent point The arc length between the point of tangency B; tangent point with tangent point The arc length between them.

[0053] in, The length is calculated using the following formula:

[0054] (2);

[0055] In the formula, ( () are the coordinates of the tangent point B; Let C be the coordinates of the tangent point C, where...

[0056] (3);

[0057] (4);

[0058] (5);

[0059] (6);

[0060] (7);

[0061] (8);

[0062] (9);

[0063] (10);

[0064] The length is calculated using the following formula:

[0065] (11);

[0066] In the formula, ( () is the tangent point The coordinates are calculated using the following formula:

[0067] (12);

[0068] (13);

[0069] ;

[0070] The length is calculated using the following formula:

[0071] ;

[0072] In the formula, ( ( ) are the coordinates of the tangent point C; () is the tangent point The coordinates of, where,

[0073] ;

[0074] ;

[0075] ;

[0076] ;

[0077] ;

[0078] Substituting formulas (2)-(20) into formula (1) will establish the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value.

[0079] In this embodiment, tangent points B, C, and The specific process for calculating the coordinates is as follows:

[0080] For a sleeper, the coordinates of any point on its circle are ( The following relationship exists between the radius and the radius: (twenty one);

[0081] For a primary anchor knapsack, the coordinates of any point on its circle are ( The following relationship exists between the radius and the radius: (twenty two);

[0082] Let line segment If the slope is k, then the equation of the tangent line is: line segment The slope is Then the equation of the tangent line is: If the slope of line segment C1C2 is k1, then ;

[0083] The angle between C1 and C2 is ,so ;

[0084] Since B and C are the points of tangency of the common tangent, and C1B and C2C are the radii of the two circles passing through the points of tangency, C1B⊥AC, C2C⊥AC, and C1B∥C2C.

[0085] Draw a perpendicular line C1D through the center C1 of the circle. C1D⊥C2C, and the perpendicular point is D. Therefore, C1D∥AC, and C1B= DC=r.

[0086] Therefore, ∠BAC1 = ∠DC1C2 = DC2 = C2C - DC = Rr;

[0087] Depend on According to the relationship between sides and angles and the Pythagorean theorem, Solving for or .

[0088] From the center point C1 to the common tangent The distance is r, so Solving for ,so The corresponding tangent equation is expressed as:

[0089] (twenty three);

[0090] The corresponding tangent equation is expressed as:

[0091] (twenty four);

[0092] By combining (21), (23), and (24), we can obtain B. The coordinates of the point:

[0093] ;

[0094] ;

[0095] ;

[0096] .

[0097] Similarly, by combining (22), (23), and (24), we can obtain... and C coordinate:

[0098] ;

[0099] ;

[0100] ;

[0101] ;

[0102] ;

[0103] ;

[0104] ;

[0105] ;

[0106] ;

[0107] .

[0108] After calculating the tangent points B and C, and After obtaining the coordinates, calculate the arc according to the following steps. Arc length:

[0109] First, calculate line segment B. Length, ;

[0110] Secondly, calculation Angle: ;

[0111] Finally, based on line segment B Length and The angle is calculated to obtain the arc. Arc length:

[0112] .

[0113] After calculating the coordinates of the tangency points B and C, calculate the line segment according to the following steps. Length:

[0114] .

[0115] After calculating the tangent points B and C, and After obtaining the coordinates, calculate the arc according to the following steps. Arc length:

[0116] First, calculate line segment CC. Length, ;

[0117] Secondly, calculation Angle: ;

[0118] Finally, based on line segment CC Length and The angle is calculated to obtain the arc. Arc length:

[0119] .

[0120] Since the above calculation process is relatively complex, this invention uses the commonly used main anchor backpack size and main cable angle, and substitutes the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value to obtain the following table, which facilitates the query of relevant parameters during construction.

[0121] Table 1 Application of Backpack Padding, Sleepers, and Adjustment Cable Length

[0122]

[0123] S2, the main anchor of the cable system is padded with sleepers. The thickness of the sleepers padded is the same as the thickness of the sleepers calculated in step S1, so that the sag of the main cable in the middle span can be adjusted to the set value.

[0124] The method described above for adjusting the main cable length by inserting sleepers into the anchor backpack of the cable system establishes a relationship between the radius of the main anchor backpack, the thickness of the sleepers, and the adjustment value of the cable length through analytical geometry. Given that the radius of the main anchor backpack and the adjustment value of the cable length are known, the thickness value of the main anchor backpack can be obtained relatively accurately based on the relationship. During the adjustment of the main cable sag, the adjustment can be completed quickly by inserting sleepers, avoiding repeated operations during construction and thus improving construction efficiency.

[0125] The above description is a detailed description of the preferred embodiments of the present invention. However, the embodiments are not intended to limit the scope of the patent application of the present invention. All equivalent changes or modifications made under the technical spirit of the present invention should fall within the patent scope covered by the present invention.

Claims

1. A method for adjusting the length of the main cable in a cable system by inserting sleepers into the main anchor backpack of the cable system, thereby increasing the length of the main cable wound around the backpack and reducing the sag of the mid-span main cable, characterized in that... Includes the following steps: S1. Through analytical geometry, establish the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value. Given that the backpack radius and cable length adjustment value are known, substitute the known main anchor backpack radius and cable length adjustment value into the established relationship to calculate the sleeper thickness. S2, the main anchor of the cable system is padded with sleepers. The thickness of the sleepers padded is the same as the thickness of the sleepers calculated in step S1, so that the sag of the main cable in the middle span can be adjusted to the set value.

2. The method for adjusting the main cable length using ground anchor backpack padding sleepers in a cable system as described in claim 1, characterized in that, Establish a rectangular coordinate system with the center of the sleeper of the padding as the origin, the x-axis as the horizontal line, and the y-axis as the vertical line; denoted as C2, the center of the main anchor backpack, and its coordinates are ( , The radius R of the main anchor backpack is a known quantity; the center of the sleeper is denoted as C1, with coordinates (0, 0), and the radius r is a quantity to be determined, where r is the thickness of the sleeper; let... and Let B be the common tangent between the main anchor backpack and the sleeper. The point of tangency with the sleeper, For the common tangent The point of tangency with the sleeper; C is the common tangent. The point of tangency with the main anchor backpack, C', is the common tangent. The point of tangency with the main anchor backpack; Let the horizontal angle between the lines connecting the centers of the main anchor backpack and the sleeper be the same as the angle of the main cable, and this is a known quantity; then the cable length adjustment value is... Calculate according to the following formula: （1）； In the formula, The distance between tangent point C and tangent point B; tangent point The arc length between the point of tangency B; tangent point with tangent point The arc length between them.

3. The method for adjusting the main cable length using ground anchor backpack padding sleepers in a cable system as described in claim 2, characterized in that... The length is calculated using the following formula: （2）； In the formula, ( () are the coordinates of the tangent point B; Let C be the coordinates of the tangent point C, where... （3）； （4）； （5）； （6）； （7）； （8）； （9）； （10）。 4. The method for adjusting the main cable length using ground anchor backpack padding sleepers in a cable system as described in claim 3, characterized in that, The length is calculated using the following formula: （11）； In the formula, ( () is the tangent point The coordinates are calculated using the following formula: （12）； （13）； 。 5. The method for adjusting the main cable length using ground anchor backpack padding sleepers in a cable system as described in claim 4, characterized in that... The length is calculated using the following formula: ； In the formula, ( () are the coordinates of the tangent point C; () is the tangent point The coordinates of, where, ； ； ； ； ； Substituting formulas (2)-(20) into formula (1) will establish the relationship between the main anchor backpack radius, sleeper thickness and cable length adjustment value.

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