Novel cable anchoring system and design method thereof

Abstract

The invention relates to the field of cable anchoring, in particular to a novel cable anchoring system and a design method thereof.The novel cable anchoring system comprises an anchor cup, a through main anchor cavity is formed in the anchor cup, a front end hole is formed in one end of the main anchor cavity, a rear end hole is formed in the other end of the main anchor cavity, and the aperture of the rear end hole is larger than that of the front end hole; at least two secondary circular truncated cone surfaces are arranged on the inner wall of the main anchor cavity, the inner diameters of the secondary circular truncated cone surfaces are gradually increased from the front end to the rear end, step transition faces are arranged between the adjacent secondary circular truncated cone surfaces, and the inner sides of the step transition faces incline towards the front end hole. And the inner diameter of the secondary circular truncated cone surface on the front side of the step transition surface is smaller than that of the rear secondary circular truncated cone surface. According to the novel cable anchoring system, the step transition face is matched with the secondary circular truncated cone surface, the peak stress level of the anchor cup and the casting body can be effectively reduced on the whole through the multi-stage circular truncated cone anchor cavity structure, the stress distribution of the inner surface of the anchor cup is more uniform and reasonable, and sliding deformation of the casting body is reduced; therefore, the static performance and the fatigue performance of the anchoring system are improved.

Description

Technical Field

[0001] The invention relates to a cable, and in particular to a novel cable anchoring system and a design method thereof. Background Art

[0002] The cable is the lifeline of the cable-bearing bridge, and the anchor cup is an indispensable and important part of the cable strand, playing the role of connection, anchoring and force transmission. The cable axial force is completely transmitted to the anchor through the anchor cup, so the anchoring performance and force condition of the anchor cup are crucial to the safety of the cable strand.

[0003] As the strength of steel wire materials in bridge cables continues to increase, the tension of cable strands continues to increase, and the requirements for anchor cup reliability and durability are also constantly increasing. When conventional cable anchor cup structures are subjected to higher levels of tensile loads, they are prone to problems such as excessive local stress peaks, excessive deformation, reduced anchoring efficiency, and insufficient fatigue performance, making it difficult to meet the anchoring requirements of high-strength cables. Simply increasing the geometric dimensions of conventional anchor cups can no longer meet actual engineering needs, and there is an urgent need to develop bridge cable anchor cup structures with high fatigue resistance and matching strength.

[0004] To solve the above problems, a patent (publication number: CN113802455A) discloses an anchor cup for carbon fiber parallel cables and an anchoring method thereof. The anchor cup is mainly configured by setting a plurality of secondary frustum cone surfaces, and making the cone angle of the secondary frustum cone surface greater than the cone angle of the original surface to be concave. The additional radial constraint effect is mainly provided by enlarging the cone angle of the secondary frustum cone surface, but the effect is limited in actual use. Summary of the invention

[0005] The purpose of the present invention is to overcome the problem in the background art that additional radial restraint is provided by enlarging the cone angle of the secondary frustum surface, but the effect is limited in actual use, and to provide a new cable anchoring system and a design method thereof.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] A novel cable anchoring system comprises an anchor cup, wherein: the anchor cup is provided with a through main anchor cavity, so that one end of the main anchor cavity has a front end hole, and the other end has a rear end hole; the inner wall of the main anchor cavity is provided with at least two secondary frustum surfaces in sequence along the through direction of the main anchor cavity, so that the main anchor cavity forms at least two frustum anchor cavities, and a step transition surface is provided between adjacent secondary frustum surfaces; along the direction from the front end hole to the rear end hole, the inner diameter of the secondary frustum surface and the inner diameter of the step transition surface both increase.

[0008] The novel cable anchoring system described in the present application increases the inner diameter of the secondary conical surface and the inner diameter of the step transition surface in the direction from the front end hole to the rear end hole. It can be concluded that the inner diameter of each secondary conical surface close to the front end hole is smaller than the inner diameter of the other end. When the casting moves relative to the anchor cup toward the front end hole or has a tendency to move relative to the anchor cup, the casting abuts the step transition surface and the secondary conical surface. On the basis of the axial pressure-bearing effect provided by the secondary conical surface, additional axial pressure-bearing effect is provided by the step transition surface. At the same time, the secondary conical surfaces of each stage can provide the combined effect of axial and radial pressure. The novel cable anchoring system described in the present application, through the step transition surface and the secondary conical surface, the multi-stage conical anchor cavity structure can generally effectively reduce the peak stress level of the anchor cup and the casting, make the stress distribution on the inner surface of the anchor cup more uniform and reasonable, and reduce the slip deformation of the casting, thereby improving the static performance and fatigue performance of the anchoring system.

[0009] Preferably, at least two adjacent secondary frustum surfaces are parallel to each other to facilitate the manufacture of the anchor cup.

[0010] Preferably, the length of the secondary frustum surface is greater than the length of the adjacent step transition surface.

[0011] Preferably, the secondary frustum surface transitions continuously with the adjacent step transition surface.

[0012] Preferably, the inner diameter of the secondary frustum surface gradually increases in the direction from the front end hole to the rear end hole.

[0013] Preferably, the inner diameter of the step transition surface gradually increases along the direction from the front end hole to the rear end hole.

[0014] Preferably, the secondary frustum is roughened on its surface.

[0015] Preferably, pits are arranged on the surface of the secondary frustum.

[0016] Preferably, protrusions are arranged on the surface of the secondary frustum.

[0017] Preferably, an inner recess is provided on the step transition surface.

[0018] Preferably, a first protrusion is provided on the step transition surface.

[0019] Preferably, the bottom of the inner recess is inclined toward the front end hole.

[0020] Preferably, the cross-sectional line of the secondary frustum surface along the axial direction is a straight line, a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a clothoid curve.

[0021] Preferably, a new type of cable anchoring system described in the present application further includes a steel wire strand, the main anchor cavity is filled with a casting, the casting is in contact with the secondary frustum surface and the step transition surface, the steel wire strand passes through the front end hole, and at least a portion of the steel wire strand is located in the casting.

[0022] The present application discloses a novel cable anchoring system, during installation and use, the end of the steel wire strand is passed through the front end hole and then split to form multiple steel wire strands, the main anchor cavity of the anchor cup is filled with a casting for fixing the steel wire separated at the end of the steel wire strand, the aperture of the rear end hole is larger than the aperture of the front end hole, the inner diameter of the secondary truncated cone surface gradually increases from the front end hole to the rear end hole, a step transition surface is arranged between adjacent secondary truncated cone surfaces, the inner side of the step transition surface is inclined toward the front end hole, the inner diameter of the secondary truncated cone surface on the side of the step transition surface close to the front end hole is smaller than the inner diameter of the secondary truncated cone surface on the side of the step transition surface away from the front end hole, it can be concluded that the diameter of each secondary truncated cone surface close to the front end hole is smaller than the diameter of the other end, and the diameter values ​​are all between the aperture diameter of the front end hole and the aperture diameter of the rear end hole, when the steel wire rope When the strand is pulled, the steel wire can drive the casting to move toward the front end hole relative to the anchor cup or have a tendency to move relatively. At this time, the casting can abut the step transition surface, and provide additional axial pressure-bearing effect through the step transition surface between several secondary cones. At the same time, since the inner diameter of the secondary cone surface on the side of the step transition surface close to the front end hole is smaller than the inner diameter of the secondary cone surface on the side of the step transition surface away from the front end hole, the secondary cone surfaces of each stage can provide the combined effect of axial and radial pressure bearing. The new cable anchoring system described in the present application, through the step transition surface and the secondary cone surface, the multi-stage cone anchor cavity structure can generally effectively reduce the peak stress level of the anchor cup and the casting, make the stress distribution on the inner surface of the anchor cup more uniform and reasonable, and reduce the slip deformation of the casting, thereby improving the static performance and fatigue performance of the anchoring system.

[0023] Preferably, a wire guide sleeve is also provided in the main anchor cavity, the wire rope strand passes through the wire guide sleeve, and the part of the wire rope strand located between the wire guide sleeve and the rear end hole is divided and forms at least three strands of steel wire, the inner wall of the wire guide sleeve has a curvature that continuously changes along the opening direction of the wire guide sleeve, the part of the inner wall of the wire guide sleeve close to the front end hole is smoothly tangent to the outer wall of the corresponding part of the wire rope strand, and the part of the inner wall of the wire guide sleeve close to the rear end hole is smoothly tangent to the outermost layer of steel wire after the wire rope strand is divided.

[0024] In conventional anchoring systems, the steel wires are closely arranged when entering the small port of the anchor cup, and because a wire dividing plate is provided at the large port of the anchor cup, the starting point and the end point of each steel wire are determined, so that the steel wires are in a broken line in the anchor cup, and the steel wires have a folded angle at the small port, which makes this part prone to fatigue fracture under the action of recycle load. In this application, a steel wire guide sleeve is provided, the purpose of which is to allow the outermost steel wires in the steel wire strand to transition according to the inner wall curve of the steel wire guide sleeve when spreading, and the steel wires in the inner layer of the steel wire strand to transition according to the curve of the adjacent outer wire when spreading, effectively avoiding at least most of the steel wire folded angles, and effectively improving the fatigue resistance of the steel wires in this part.

[0025] Preferably, the wire guide sleeve is arranged in a trumpet shape.

[0026] Preferably, in the cross-sectional direction of the wire guide sleeve, the inner wall of the wire guide sleeve is in a polygonal shape.

[0027] Preferably, along the opening direction of the wire guide sleeve, the cross-sectional line of the inner surface of the wire guide sleeve includes a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a clothoid curve.

[0028] Preferably, the wall thickness of the anchor cup gradually increases along the direction from the free end to the load-bearing end of the anchor cup. The free end is the large-mouth end, the load-bearing end is the small-mouth end, and the wall thickness of the anchor cup gradually increases from the large-mouth end to the small-mouth end, so that the anchor cup can bear better force.

[0029] Preferably, the diameter of the rear end hole is larger than the diameter of the front end hole.

[0030] Preferably, the anchor cup can be used for a main cable, a sling or a stay cable.

[0031] The present application also discloses a design method for the novel cable anchoring system described in the present application, comprising the following steps:

[0032] S1. Determine the surface position of the main anchor cavity based on the front end hole diameter and the rear end hole diameter;

[0033] S2. Determine the length of each secondary frustum surface;

[0034] S3. Determine the end position of the secondary truncated cone surface close to the front end hole based on the length of the secondary truncated cone surface and the main anchor cavity surface position;

[0035] S4. Determine the angle of the secondary frustum surface relative to the main anchor cavity surface;

[0036] S5. Determine the angle of the step transition surface relative to the secondary truncated cone surface based on the angle of the secondary truncated cone surface relative to the main anchor cavity surface.

[0037] The present application also discloses another design method for a novel cable anchoring system, comprising the following steps:

[0038] A1. Analyze the influence of stress distribution results of the cable anchorage system benchmark model on the performance of the anchor cup and casting;

[0039] A2. Combine the key parameters of the anchor cup to form multiple combination models;

[0040] A3. Analyze the stress distribution and stress peak of the anchor cup and the casting based on at least some of the key parameters of each combination model, and determine the influence of the key parameters;

[0041] A4. Optimize the anchor cup, casting and steel wire based on the influence rules of each key parameter to form the new cable anchoring system model;

[0042] A5. Evaluate and analyze the improvement effect of the novel cable anchoring system model and the cable anchoring system benchmark model in terms of fatigue resistance.

[0043] The present application describes a design method for a novel cable anchoring system, which analyzes the influence of stress distribution results of a cable anchoring system benchmark model on the performance of an anchor cup and a casting; combines key parameters of the anchor cup to form a plurality of combined models; analyzes the stress distribution and stress peak values ​​of at least some key parameters on the anchor cup and the casting based on each combined model, and determines the influence rules of the key parameters; finds the optimization direction, and then optimizes the anchor cup, casting and steel wire, and then confirms the improvement effect of the optimized novel cable anchoring system in terms of fatigue resistance through the improvement effect in terms of fatigue resistance, so that the stress of the anchor cup, casting and steel wire in the novel cable anchoring system is more optimized.

[0044] Preferably, the key parameters of the anchor cup include anchoring length, anchor cup diameter, inclination angle of the anchor cup wall, relative wall thickness of the front and rear ends of the anchor cup, average wall thickness of the anchor cup, friction coefficient between the casting and the anchor cup, anchor cavity structure and chamfer of the inner wall of the anchor cup.

[0045] Preferably, in step A2, the key parameters of the anchor cup are combined as follows:

[0046]

[0047]

[0048] Preferably, step A3 specifically comprises:

[0049] By analyzing the stress distribution and stress peak of the anchor cup and casting of the combined models M1-M4 with different anchor lengths at the serviceability limit state and the bearing capacity limit state, the influence of the anchor length parameter is determined.

[0050] By analyzing the stress distribution and stress peak of the anchor cup and casting of the combined models M5-M8 with different inner diameters of the loaded end at the serviceability limit state and the bearing capacity limit state, the influence law of the inner diameter parameter of the loaded end is determined.

[0051] By analyzing the stress distribution of the anchor cup and casting of the combined models M9-M13 with different inclination angles of the anchor cup wall at the serviceability limit state and the bearing capacity limit state, the influence law of the inclination angle parameters of the anchor cup wall is determined.

[0052] By analyzing the stress distribution of the anchor cup and casting of the combined models M14-M17 with different relative wall thicknesses at the front and rear ends of the anchor cup at the serviceability limit state and the bearing capacity limit state, the influence of the relative wall thickness parameters at the front and rear ends of the anchor cup is determined.

[0053] By analyzing the stress distribution of the anchor cup and casting of the combined models M18-M21 with different average wall thicknesses at the front and rear ends of the anchor cup at the serviceability limit state and the bearing capacity limit state, the influence of the average wall thickness parameters at the front and rear ends of the anchor cup is determined.

[0054] By analyzing the stress distribution of the anchor cup and casting of the combined models M22-M25 with different friction coefficients of the contact surface between the anchor cup and the casting at the normal service limit state and the bearing capacity limit state, the influence law of the friction coefficient parameters of the contact surface between the anchor cup and the casting is determined.

[0055] By analyzing the stress distribution of the anchor cup and casting of the combined models M26-M27 with different anchor cup and anchor cavity structures at the serviceability limit state and the bearing capacity limit state, the influence of the anchor cup and anchor cavity structural parameters was determined.

[0056] By analyzing the stress distribution of the anchor cup and casting of the combined model M29 with chamfers at the serviceability limit state and the bearing capacity limit state, the influence of chamfer parameters was determined.

[0057] Preferably, the key parameter influence rules are as follows:

[0058]

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] The novel cable anchoring system described in the present application increases the inner diameter of the secondary conical surface and the inner diameter of the step transition surface in the direction from the front end hole to the rear end hole. It can be concluded that the inner diameter of each secondary conical surface close to the front end hole is smaller than the inner diameter of the other end. When the casting moves relative to the anchor cup toward the front end hole or has a tendency to move relative to the anchor cup, the casting abuts the step transition surface and the secondary conical surface. On the basis of the axial pressure-bearing effect provided by the secondary conical surface, additional axial pressure-bearing effect is provided by the step transition surface. At the same time, the secondary conical surfaces of each stage can provide the combined effect of axial and radial pressure. The novel cable anchoring system described in the present application, through the step transition surface and the secondary conical surface, the multi-stage conical anchor cavity structure can generally effectively reduce the peak stress level of the anchor cup and the casting, make the stress distribution on the inner surface of the anchor cup more uniform and reasonable, and reduce the slip deformation of the casting, thereby improving the static performance and fatigue performance of the anchoring system. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is a schematic longitudinal section diagram of a novel cable anchoring system of the present application.

[0062] Figure 2 For this application Figure 1 Enlarged view of part A in the middle (the cross-sectional line of the secondary cone surface along the axial direction is a straight line).

[0063] Figure 3 For this application Figure 2 Enlarged view of part B in the middle.

[0064] Figure 3 a is the Figure 2 Enlarged view of part B in the middle (the cross-sectional line of the step transition surface along the axial direction is a straight line).

[0065] Figure 3 b is the Figure 2 Enlarged view of part B in the middle (there is an inner concave portion and a first convex portion on the step transition surface).

[0066] Figure 4 For this application Figure 1 Enlarged view of part A in the middle.

[0067] Figure 4 a is the Figure 1 Enlarged view of part A in the middle (the cross-sectional line along the axial direction of the secondary cone surface is a transition curve).

[0068] Figure 4 b is the Figure 1 Enlarged view of part A in the middle (there are some pits and protrusions on the surface of the secondary cone).

[0069] Figure 5This is a schematic longitudinal section diagram of a novel cable anchoring system of the present application (with a wire guide sleeve).

[0070] Figure 6 For this application Figure 5 Enlarged view of part C in the middle (with wire guide sleeve).

[0071] Figure 7 For this application Figure 6 Enlarged view of part D in the middle.

[0072] Figure 7 a is the Figure 6 Enlarged view of the middle D part (with a wire guide sleeve, the cross-sectional line of the step transition surface along the axial direction is a straight line).

[0073] Figure 7 b is the Figure 6 Enlarged view of the middle D part (with a wire guide sleeve, an inner concave portion and a first convex portion on the step transition surface).

[0074] Figure 8 This is a schematic longitudinal section diagram of a novel cable anchoring system of the present application.

[0075] Fig. 9 This is a schematic longitudinal section diagram of the wire guide sleeve of the present application.

[0076] Fig. 9 a is a schematic diagram of the longitudinal section of the wire guide sleeve of the present application (the inner wall is similar to a hexagonal cone).

[0077] Fig. 9 b is a left view schematic diagram of the wire guide sleeve of the present application (the inner wall is similar to a hexagonal cone).

[0078] Fig.10 This is a schematic longitudinal section diagram of the wire guide sleeve of the present application.

[0079] Fig.10 a is a schematic diagram of the longitudinal section of the wire guide sleeve of the present application (the inner wall is similar to a cone).

[0080] Fig.10 b is a left view schematic diagram of the wire guide sleeve of the present application (the inner wall is similar to a cone).

[0081] Fig.11 Comparison of anchor cup stress amplitude and casting compressive stress amplitude before and after optimization of this application.

[0082] Fig.12 The stress curve and broken line graph of the anchor cup of the present application along the length direction after optimization.

[0083] Fig.13The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction after optimization.

[0084] Fig.14 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0085] Fig.15 This is the parameter structure diagram of the anchor cup finite element analysis of this application.

[0086] Fig.16 Schematic diagram of parameters and stress distribution of the anchor cup benchmark model of this application.

[0087] Fig.17 The stress curve and broken line graph of the anchor cup of the present application along the length direction at different anchoring lengths.

[0088] Fig.18 The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction at different anchoring lengths.

[0089] Fig.19 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0090] Fig. 20 The stress curve and broken line diagram of the anchor cup of the present application along the length direction at different inner diameters of the loaded end.

[0091] Fig.21 The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction at different inner diameters of the loaded end.

[0092] Fig. 22 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0093] Fig.23 The stress curve and broken line diagram of the anchor cup of the present application along the length direction at different inclination angles.

[0094] Fig.24 The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction at different inclination angles.

[0095] Fig.25 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0096] Fig.26 The stress curve and broken line diagram of the anchor cup of the present application along the length direction under different relative wall thicknesses at the front and rear ends.

[0097] Fig. 27 The stress curve and broken line diagram along the thickness direction of the anchor cup of the present application under different relative wall thicknesses at the front and rear ends.

[0098] Fig.28 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0099] Fig.29 The stress curve and broken line diagram of the anchor cup of the present application along the length direction at different average wall thicknesses.

[0100] Fig.30 The stress curve and broken line diagram along the thickness direction of the anchor cup of the present application at different average wall thicknesses.

[0101] Fig.31 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0102] Fig.32 The stress curve and broken line graph of the anchor cup of the present application along the length direction under different friction coefficients.

[0103] Fig.33 The stress curve and broken line graph of the anchor cup of the present application along the thickness direction under different friction coefficients.

[0104] Fig.34 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0105] Fig.35 The stress curve and broken line diagram of the anchor cup of the present application along the length direction under different anchor cavity multi-level structures.

[0106] Fig.36 The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction under different anchor cavity multi-level structures.

[0107] Fig.37 This is the stress cloud diagram of the anchor cup-casting of the anchor cavity forward multi-stage and reverse multi-stage structures of the present application.

[0108] Fig.38 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0109] Fig.39 The stress curve and broken line diagram of the anchor cup of the present application along the length direction under different anchor cup inner wall chamfers.

[0110] Fig.40 The stress curve and broken line diagram of the anchor cup of the present application along the thickness direction under different anchor cup inner wall chamfers.

[0111] Fig.41 It is the radial and circumferential stress trend diagram of the casting and the anchor cup-casting relative slip line diagram of this application.

[0112] Fig.42 This is a schematic diagram of the cooperation between the steel wire strand and the steel wire guide sleeve of the present application.

[0113] Fig.43 Stress cloud diagram of anchor cup-casting in the positive multi-level structure of anchor cavity. DETAILED DESCRIPTION

[0114] The present invention is further described in detail below in conjunction with test examples and specific implementation methods. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0115] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0116] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0117] In addition, the expressions “first”, “second”, “third”, etc. that appear in the terms are merely descriptions used to distinguish the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0118] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0119] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0120] Example 1

[0121] like Figure 1-10 As shown, a novel cable anchoring system described in this embodiment includes an anchor cup 1, wherein: a through main anchor cavity 6 is arranged on the anchor cup 1, so that one end of the main anchor cavity 6 has a front end hole 7, and the other end has a rear end hole 8; the inner wall of the main anchor cavity 6 is sequentially provided with at least two secondary frustum surfaces 10 along the through direction of the main anchor cavity 6, so that the main anchor cavity 6 forms at least two frustum anchor cavities 11, and a step transition surface 15 is arranged between adjacent secondary frustum surfaces 10; along the direction from the front end hole 7 to the rear end hole 8, the inner diameter of the secondary frustum surface 10 and the inner diameter of the step transition surface 15 both increase.

[0122] The present application discloses a novel cable anchoring system. In the direction from the front hole 7 to the rear hole 8, the inner diameter of the secondary truncated cone surface 10 and the inner diameter of the step transition surface 15 are increased. It can be concluded that the inner diameter of one end of each secondary truncated cone surface 10 close to the front hole 7 is smaller than the inner diameter of the other end. When the casting 2 moves relative to the anchor cup 1 toward the front hole 7 or has a tendency to move relative to the anchor cup 1, the casting 2 abuts against the step transition surface 15 and the secondary truncated cone surface 10, providing a basis for axial pressure bearing on the secondary truncated cone surface 10. On this basis, additional axial pressure-bearing effect is provided by the step transition surface 15, and at the same time, the secondary truncated cone surface 10 of each level can provide the combined effect of axial pressure and radial pressure-bearing. The novel cable anchoring system described in this invention, through the step transition surface 15 and the secondary truncated cone surface 10, the multi-stage truncated cone anchor cavity 11 structure can generally effectively reduce the peak stress level of the anchor cup 1 and the casting 2, make the stress distribution on the inner surface of the anchor cup 1 more uniform and reasonable, and reduce the slip deformation of the casting 2, thereby improving the static performance and fatigue performance of the anchoring system.

[0123] Along the direction from the front end hole 7 to the rear end hole 8, the inner diameter of the secondary frustum surface 10 increases as follows: the cross-sectional diameter of the secondary frustum surface 10 close to the front end hole 7 is smaller than the cross-sectional diameter of the secondary frustum surface 10 close to the rear end hole 8.

[0124] Along the direction from the front end hole 7 to the rear end hole 8, the inner diameter of the step transition surface 15 increases as follows: the cross-sectional diameter of the step transition surface 15 close to the front end hole 7 is smaller than the cross-sectional diameter of the step transition surface 15 close to the rear end hole 8.

[0125] Specifically, preferably, at least two adjacent secondary truncated cone surfaces 10 are parallel to facilitate the manufacture of the anchor cup 1; an inner concave portion 16 is provided on the step transition surface 15; a first convex portion 17 is provided on the step transition surface 15; the bottom of the inner concave portion 16 is inclined toward the front end hole 7; a pit 12 is provided on the secondary truncated cone surface 10. A convex portion 13 is provided on the secondary truncated cone surface 10.

[0126] The wall thickness of the load-bearing end of the anchor cup 1 is greater than the wall thickness of the free end of the anchor cup 1 .

[0127] The anchor cup 1 can be used for a main cable, a sling or a stay cable.

[0128] A novel cable anchoring system described in the present application, when installed and used, the end of the steel wire strand 14 is passed through the front end hole 7 and then separated to form multiple strands of steel wire 3, the main anchor cavity 6 of the anchor cup 1 is filled with a casting 2, which is used to fix the steel wire 3 separated at the end of the steel wire strand 14, the aperture of the rear end hole 8 is larger than the aperture of the front end hole 7, the inner diameter of the secondary frustum surface 10 gradually increases from the front end hole 7 to the rear end hole 8, and a step transition surface 15 is provided between adjacent secondary frustum surfaces 10, the inner side of the step transition surface 15 is inclined toward the front end hole 7, the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 close to the front end hole 7 is smaller than the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 away from the front end hole 7, it can be concluded that the diameter of each secondary frustum surface 10 close to the front end hole 7 is smaller than the diameter of the other end, and the diameter values ​​are all between the aperture of the front end hole 7 and the aperture of the rear end hole 8. When the steel wire strand 14 is pulled, the steel wire 3 can drive the casting 2 to move toward the front end hole 7 relative to the anchor cup 1 or have a tendency to move relatively. At this time, the casting 2 can abut the step transition surface 15, and provide additional axial pressure-bearing effect through the step transition surface 15 between the secondary frustums. At the same time, since the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 close to the front end hole 7 is smaller than the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 away from the front end hole 7, the secondary frustum surfaces 10 of each level can provide the combined effect of axial and radial pressure bearing. The novel cable anchoring system described in the present invention, through the step transition surface 15 and the secondary frustum surface 10, the multi-stage frustum anchor cavity 11 structure can generally effectively reduce the peak stress level of the anchor cup 1 and the casting 2, make the stress distribution on the inner surface of the anchor cup 1 more uniform and reasonable, and reduce the sliding deformation of the casting 2, thereby improving the static performance and fatigue performance of the anchoring system.

[0129] Example 2

[0130] The new cable anchoring system described in this embodiment is different from that in Embodiment 1 in that the main anchor cavity 6 of the steel wire strand 14 is filled with a casting 2, the casting 2 is in contact with both the secondary frustum surface 10 and the step transition surface 15, the steel wire strand 14 passes through the front end hole 7, and at least a portion of the steel wire strand 14 is located in the casting 2.

[0131] The present application also discloses a novel cable anchoring system. During installation and use, the end of the steel wire strand 14 is passed through the front end hole 7 and then split to form multiple strands of steel wire 3. The main anchor cavity 6 of the anchor cup 1 is filled with a casting 2 for fixing the steel wire 3 separated at the end of the steel wire strand 14. The aperture of the rear end hole 8 is larger than the aperture of the front end hole 7. The inner diameter of the secondary frustum surface 10 gradually increases from the front end hole 7 to the rear end hole 8. A step transition surface 15 is provided between adjacent secondary frustum surfaces 10. The inner side of the step transition surface 15 is inclined toward the front end hole 7. The inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 close to the front end hole 7 is smaller than the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 away from the front end hole 7. It can be concluded that the diameter of each secondary frustum surface 10 close to the front end hole 7 is smaller than the diameter of the other end, and the diameter values ​​are all between the aperture of the front end hole 7 and the aperture of the rear end hole 8. When the steel wire strand 14 is pulled, the steel wire 3 can drive the casting 2 to move toward the front end hole 7 relative to the anchor cup 1 or have a tendency to move relatively. At this time, the casting 2 can abut the step transition surface 15, and provide additional axial pressure-bearing effect through the step transition surface 15 between the secondary frustums. At the same time, since the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 close to the front end hole 7 is smaller than the inner diameter of the secondary frustum surface 10 on the side of the step transition surface 15 away from the front end hole 7, the secondary frustum surfaces 10 of each level can provide the combined effect of axial and radial pressure bearing. The novel cable anchoring system described in the present invention, through the step transition surface 15 and the secondary frustum surface 10, the multi-stage frustum anchor cavity 11 structure can generally effectively reduce the peak stress level of the anchor cup 1 and the casting 2, make the stress distribution on the inner surface of the anchor cup 1 more uniform and reasonable, and reduce the sliding deformation of the casting 2, thereby improving the static performance and fatigue performance of the anchoring system.

[0132] According to a preferred embodiment, a wire guide sleeve 20 is further provided in the main anchor cavity 6, and the wire rope strand 14 passes through the wire guide sleeve 20 and is arranged in separate wires. The curvature of the inner wall 19 of the wire guide sleeve 20 continuously changes along the opening direction of the wire guide sleeve 20. The portion of the inner wall 19 of the wire guide sleeve 20 close to the front end hole 7 is smoothly tangent to the corresponding portion of the wire rope strand 14, and the portion of the inner wall 19 of the wire guide sleeve 20 close to the rear end hole 8 is smoothly tangent to the outermost layer of the wire 3 corresponding to the wire rope strand 14.

[0133] More specifically, a wire guide sleeve 20 is also provided in the main anchor cavity 6, the wire rope strand 14 passes through the wire guide sleeve 20, and the wire rope strand 14 is partially divided between the wire guide sleeve 20 and the rear end hole 8 to form at least three strands of steel wire 3, the inner wall 19 of the wire guide sleeve 20 has a curvature that continuously changes along the opening direction of the wire guide sleeve 20, the portion of the inner wall 19 of the wire guide sleeve 20 close to the front end hole 7 is smoothly tangent to the outer wall of the corresponding portion of the wire rope strand 14, and the portion of the inner wall 19 of the wire guide sleeve 20 close to the rear end hole 8 is smoothly tangent to the outermost layer of steel wire 3 after the wire rope strand 14 is divided.

[0134] like Fig.42 As shown, in the conventional anchoring system, the steel wires are closely arranged when entering the small port of the anchor cup, and because a wire dividing plate is set at the large port of the anchor cup, the starting point and the end point of each steel wire are determined, so that the steel wires are in a broken line in the anchor cup, and the steel wires have a folded angle at the small port, which makes this part prone to fatigue fracture under the action of recycle load. In the present application, the steel wire guide sleeve 20 is set to allow the outermost steel wire 3 in the steel wire strand 14 to transition according to the inner wall curve of the steel wire guide sleeve 20 when spreading, and the steel wire 3 in the inner layer of the steel wire strand 14 to transition according to the curve of the adjacent outer layer steel wire 3 when spreading, effectively avoiding at least most of the steel wires 3 folding angles, and effectively improving the fatigue resistance of the steel wire 3 in this part.

[0135] In a preferred solution, the wire guide sleeve 20 is configured in a trumpet shape.

[0136] In a preferred solution, in the cross-sectional direction of the wire guide sleeve 20 , the inner wall 19 of the wire guide sleeve 20 is in a polygonal shape.

[0137] In a preferred embodiment, along the opening direction of the wire guide sleeve 20, the cross-sectional line of the inner surface of the wire guide sleeve 20 is a straight line, a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a clothoid curve.

[0138] Or another preferred solution is that along the opening direction of the wire guide sleeve 20, the cross-sectional line of the inner surface of the wire guide sleeve 20 is a combination of a straight line and a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a spiral curve.

[0139] The novel cable anchoring system described in the present application can be specifically used as a hot-cast anchor cup 1 suitable for parallel steel wire 3 cables.

[0140] In view of the problems existing in the new cable anchoring system mentioned in the background technology, this embodiment proposes a new anchor cavity structure to improve the stress performance of the anchor cup 1 structure and improve the static bearing capacity and fatigue bearing capacity of the anchor cup 1 for anchoring the casting 2 and the steel wire 3.

[0141] Anchor cup 1 structure: The anchor cup 1 structure is preferably composed of an anchor cup 1, a casting 2, parallel steel wire strands 14, a steel wire guide sleeve 20, and a rear end wire dividing plate 5.

[0142] Multi-stage truncated cone anchor cavity 11: A truncated cone-shaped main anchor cavity 6 is provided in the middle of the anchor cup 1 structure, wherein the front end hole 7 of the anchor cup 1 is smaller, the rear end hole 8 is larger, and the main anchor cavity surface 9 has a single taper angle. On the basis of the main anchor cavity surface 9, a plurality of secondary truncated cone surfaces 10 connected by step transition surfaces 15 are further provided, thereby changing the surface shape of the main anchor cavity 6 to form a multi-stage truncated cone anchor cavity 11. All the secondary truncated cone surfaces 10 have a consistent taper angle and length, and the front end diameter of each secondary truncated cone surface 10 is smaller than the rear end diameter, and the diameter value is between the diameter of the front end hole 7 and the diameter of the rear end hole 8. The connection between the step transition surface 15 and the adjacent secondary truncated cone surface 10 adopts an arc chamfer to avoid local stress concentration.

[0143] The present application describes a new type of cable anchoring system, in which the cone angle of the secondary truncated cone surface 10 is smaller than the cone angle of the original main anchor cavity surface 9, and is convex, and provides additional axial pressure-bearing effect mainly through the step transition surface 15 between several secondary truncated cones. Compared with the concave structure of the background technology, the constraint mechanism is different, among which the actual effect of the concave structure of the background technology is relatively limited. The present application describes a new structure. The multi-stage truncated cone anchor cavity 11 structure can generally effectively reduce the peak stress level of the anchor cup 1 and the casting 2, make the stress distribution on the inner surface of the anchor cup 1 more uniform and reasonable, and reduce the slip deformation of the casting 2, thereby improving the static performance and fatigue performance of the anchoring system.

[0144] Continuous curved truncated cone anchor cavity 11: The cross-sectional line of each secondary truncated cone surface 10 along the axial direction can be in various forms, including but not limited to straight lines, circular curves, elliptical curves, power function curves, exponential function curves, hyperbolas, and cycloids. The specific curve form selection and arrangement method can be determined according to the actual stress control requirements of the anchor cup 1. Compared with the conventional single conical anchor cavity structure, the continuous step transition surface 15 combined with the curved truncated cone anchor cavity 11 can alleviate the local stress concentration phenomenon at the front end of the anchor cup 1, adjust the stress distribution of the anchor cup 1, the casting 2 and the interface within the entire anchoring length of the anchor cup 1, and achieve low peak and smoothing of the stress of the anchor cup 1, thereby improving the static performance and fatigue performance of the anchoring system.

[0145] Rough surface: On the basis of the multi-stage truncated cone anchor cavity 11, the overall roughness of the interface between the anchor cup 1 and the casting 2 can be further improved through processing methods to form a rough surface. Sharp points or sudden changes in shape should be avoided on the rough surface. Arc chamfers are required in these places to avoid local stress concentration. At the same time, the geometric features of the rough surface should not be too prominent to avoid interfering with the spatial arrangement of the steel wire 3 in the anchor cavity. There are many methods and forms to improve the surface roughness of the anchor cavity. Among them, the preferred method for better processing control includes but is not limited to setting a number of regular or irregular local pits 12 or protrusions 13 on the main anchor cavity surface 9 to increase the contact area between the anchor cup 1 and the casting 2 and improve the mechanical bite ability; or increase the roughness of the main anchor cavity surface 9 through processing technology, thereby increasing the friction coefficient between the anchor cup 1 and the casting 2. Compared with conventional flat surfaces, rough surfaces can effectively improve the anchoring force of the anchor cup 1 on the casting 2, reduce the sliding deformation of the casting 2, and further improve the anchoring efficiency of the anchor cup 1.

[0146] New cable anchoring system type: This new cable anchoring system is applicable to main cable anchor cup 1, inclined cable anchor cup 1 or sling anchor cup 1, among which main cable anchor cup 1 can be divided into pull rod anchoring type and pressure anchoring type. For different types of new cable anchoring systems, it is only necessary to perform conventional design and structural adjustment on the external shape of the anchor cup 1 structure according to the anchoring method and force characteristics of different new cable anchoring systems, and the structural form of the internal anchor cavity will not be affected.

[0147] Parallel steel wire strands 14: Parallel steel wire strands 14 are composed of no less than 7 high-strength steel wires 3 arranged closely in a hexagon or a hexagon with missing corners. The strength of the steel wires 3 is not limited. The parallel steel wire strands 14 extend into the anchor cup 1 from the front end hole 7 of the anchor cup 1, and spread evenly in the conical anchor cavity after passing through the steel wire guide sleeve 20. The distance between adjacent steel wires 3 in the same cross section is equal. Near the rear end hole 8 of the anchor cup 1, the end of the steel wire 3 passes through the rear end wire dividing plate 5 for positioning and is subjected to pier head treatment. The steel wire 3 is anchored in the main anchor cavity 6 through the casting 2.

[0148] Wire guide sleeve 20: Wire guide sleeve 20 is arranged near the front end hole 7 of the anchor cavity. After the parallel wire strands 14 are inserted into the anchor cup 1, they first pass through the wire guide sleeve 20 and spread out evenly. The wire guide sleeve 20 is in the shape of a wire guide sleeve, tightly surrounding the outside of the wire strands 14. Its cylinder wall can be set with equal thickness. The cross-sectional line of the inner wall 19 of the wire guide sleeve 20 along the axial direction of the wire guide sleeve 20 is a gentle curve, which can be a cycloid, and the curvature of the two ends is 0 and the curvature of the middle is a constant value, so that the curvature changes continuously. The wire guide sleeve 20 ensures that the wire strands 14 maintain a smooth linear shape during the spreading process without obvious bending, thereby reducing the local stress of the steel wire 3 and improving the fatigue resistance. Its specific material can be the same alloy material as the casting 2, cold casting material, mild steel, etc. The wire guide sleeve 20 is fixed in the anchor cavity by the casting 2.

[0149] Casting 2: Casting 2 can be made of multiple alloy materials including but not limited to zinc-copper alloy, zinc-aluminum-copper alloy, etc., and is formed into a cone with steel wire 3 in the anchor cavity by hot casting. This anchor cavity structure is also applicable to cold-cast anchor cup 1. For cold-cast anchor cup 1, it is only necessary to change the casting 2 material in anchor cup 1 to a commonly used cold-cast filler, and design and pour according to the corresponding material characteristics, and the structural form of the internal anchor cavity is not affected.

[0150] Example 3

[0151] The present embodiment describes a design method for a novel cable anchoring system described in Example 1, comprising the following steps: S1. determining the position of the main anchor cavity surface 9 based on the diameter of the front end hole 7 and the diameter of the rear end hole 8; S2. determining the length of each section of the secondary frustum surface 10; S3. determining the end position of the secondary frustum surface 10 close to the front end hole 7 based on the length of the secondary frustum surface 10 and the position of the main anchor cavity surface 9; S4. determining the angle of the secondary frustum surface 10 relative to the main anchor cavity surface 9; S5. determining the angle of the step transition surface 15 relative to the secondary frustum surface 10 based on the angle of the secondary frustum surface 10 relative to the main anchor cavity surface 9.

[0152] Example 4

[0153] like Figure 1-43As shown, the design method of a new cable anchoring system described in Example 1 described in this embodiment mainly aims at stress peak reduction and structural applicability, durability and economy. By carrying out iterative design under a multi-parameter system, the finite element calculation results under the key parameter combinations of various parameters in the project, including anchoring length, anchor cup 1 diameter, anchor cup 1 wall inclination angle, relative wall thickness of front and rear ends of anchor cup 1, average wall thickness of anchor cup 1, friction coefficient between casting 2 and anchor cup 1, anchor cavity structure and chamfer of inner wall of anchor cup 1, are deeply analyzed and studied. Specifically, the following steps are included: analyzing the influence of stress distribution results of the cable anchoring system benchmark model on the performance of anchor cup 1 and casting 2; on this basis, combining various key parameters of anchor cup 1, a total of 29 combination models M1-M29, as shown in Table 1; further analysis, comprehensively examining the stress distribution of each parameter on anchor cup 1, casting 2 and steel wire 3 and its influence on fatigue performance, and finally proposing a strength matching and high fatigue resistance anchor cup 1 structural design scheme.

[0154] The average wall thickness of the anchor cup 1 is t = (load end wall thickness + free end wall thickness) / 2.

[0155] like Fig.15 As shown in the figure, the cable anchoring system benchmark model: In the cable anchoring system benchmark model, the anchoring length L is 510 mm, the radius r of the loaded end is 40.5 mm, the inner inclination angle α of the anchor cup 1 wall is 7.125°, the average wall thickness t of the anchor cup 1 is 50 mm, the friction coefficient of the contact surface between the anchor cup 1 and the casting 2 is 0.2, the inner wall of the anchor cavity is a smooth inner wall, and the inner wall of the anchor cavity has no chamfer. All the above dimensional parameters meet the parameter design values ​​of the anchor cup 1. The force study of the anchor cup 1 of the cable anchoring system benchmark model shows that the Mises stress is related to the yield of the anchor cup 1, the maximum stress is located at the contact part between the small port and the end of the casting 2, and gradually decreases along the length direction and thickness direction of the anchor cup 1. The principal tensile stress of the anchor cup 1 is related to the fatigue performance of the anchor cup 1. The position of the maximum principal tensile stress is different from the position of the maximum Mises stress, which is biased towards the large port direction and gradually decreases along the length direction and thickness direction of the anchor cup 1.

[0156] Table 1 Cable anchorage system modeling parameter setting table

[0157]

[0158] Explanation of the legends in each chart: NLT: Maximum principal tensile stress in the length direction of anchor cup 1 under the serviceability limit state; ULT: Maximum principal tensile stress in the length direction of anchor cup 1 under the ultimate bearing capacity limit state; NL-Mises: Maximum Mises stress in the length direction of anchor cup 1 under the serviceability limit state; UL-Mises: Maximum Mises stress in the length direction of anchor cup 1 under the ultimate bearing capacity limit state; NDT: Maximum principal tensile stress in the thickness direction of anchor cup 1 under the serviceability limit state; UDT: Maximum principal tensile stress in the thickness direction of anchor cup 1 under the ultimate bearing capacity limit state; ND-Mises: Maximum Mises stress in the thickness direction of anchor cup 1 under the serviceability limit state; UD-Mises: Maximum Mises stress in the thickness direction of anchor cup 1 under the ultimate bearing capacity limit state; NJ: Radial compressive stress of casting 2 under the serviceability limit state; UJ: Radial compressive stress of casting 2 under the ultimate bearing capacity limit state; NQ: Hoop compressive stress of casting 2 under the serviceability limit state; UQ: Hoop compressive stress of casting 2 under the ultimate bearing capacity limit state.

[0159] Analysis of fatigue resistance of anchor cup 1 parameters

[0160] Anchorage length L: Anchorage length refers to the effective length inside the anchor cup 1 for anchoring the cable. It directly affects the force distribution and transmission mode between the cable and the anchoring system. A longer anchorage length can provide a larger anchoring area, increase the contact area between the cable and the anchoring system, and is conducive to dispersing and reducing the force on the anchor cup 1, reducing the degree of local stress concentration, thereby improving the fatigue resistance of the anchoring system. However, an excessively long anchorage length will increase material and construction costs, may cause the anchor cup 1 to swing or vibrate, and affect the stability and reliability of the anchoring system. By analyzing the stress distribution and stress peak of the anchor cup 1 and the casting 2 of the combined models M1-M4 with different anchorage lengths at the normal use limit state and the bearing capacity limit state, the influence law of the anchorage length parameter is determined.

[0161] like Fig.17 and 18 As shown in the figure, the analysis of the two groups of results shows that the maximum principal tensile stress of anchor cup 1 is located at the contact point between the small port and the end of casting 2, and gradually decreases along the length and thickness direction of anchor cup 1, and the maximum Mises stress gradually decreases along the length and thickness direction of anchor cup 1. Under different anchoring lengths, the maximum principal tensile stress and maximum Mises stress of anchor cup 1 do not change much.

[0162] like Fig.19As shown in the figure, the analysis of the radial and hoop stress line graphs of casting 2 shows that in the normal service limit state, the radial compressive stress of casting 2 is generally greater than the hoop compressive stress. In the bearing capacity limit state, the hoop compressive stress of casting 2 is greater than the radial compressive stress, and the anchor cup 1 is in a high stress state. The relative slip line graph of anchor cup 1 and casting 2 shows that when the anchoring length is 610mm, the relative slip between anchor cup 1 and casting 2 is the smallest, but the overall change is not large.

[0163] In summary, for the anchoring length, although the stress distribution and magnitude of the anchor cup 1 vary slightly at different lengths, there is no obvious effect of improving the stress of the anchor cup 1. This may indicate that when considering the anchoring length, other factors need to be considered comprehensively, and the design needs to be further optimized to improve the performance of the anchor cup 1.

[0164] Inner diameter of the loaded end: The inner diameter of the loaded end refers to the diameter of the internal space of the anchor cup 1, which directly affects the contact area and force transfer effect between the cable and the anchor cup 1. A larger inner diameter can provide a wider anchoring area, which is conducive to the uniform distribution of force between the cable and the anchor cup 1, reduces the possibility of local stress concentration, and thus improves the fatigue resistance of the anchoring system. However, a larger inner diameter will increase the hollow part of the anchor cup 1, resulting in a decrease in material utilization, and with the increase of the inner diameter, the overall size of the anchor cup 1 will also increase, resulting in an increase in its weight, increasing the difficulty of installation and maintenance. By analyzing the stress distribution and stress peak of the anchor cup 1 and the casting 2 of the combination models M5-M8 with different inner diameters of the loaded end at the normal use limit state and the bearing capacity limit state, the influence law of the inner diameter parameters of the loaded end is determined.

[0165] like Fig. 20 and 21 As shown in the figure, the analysis of the two groups of results shows that the maximum principal tensile stress of anchor cup 1 is located at the contact point between the small port and the end of casting 2, and gradually decreases along the length and thickness direction of anchor cup 1. Under different inner diameters of the loaded end, the maximum principal tensile stress of anchor cup 1 does not change much. The maximum Mises stress gradually decreases along the length and thickness direction of anchor cup 1. When the inner diameter of the loaded end gradually increases, the maximum Mises stress of anchor cup 1 gradually decreases.

[0166] like Fig. 22 As shown in the figure, the radial and annular stress line graphs of casting 2 show that in the normal use limit state, the radial compressive stress of casting 2 is generally greater than the annular compressive stress, and the radial compressive stress of casting 2 changes greatly with the increase of the radius of the loaded end, showing an overall trend of stress reduction. In the bearing capacity limit state, the annular compressive stress and radial compressive stress of casting 2 both tend to decrease with the increase of the radius of the loaded end. The relative slip line graph of anchor cup 1 and casting 2 shows that the relative slip between anchor cup 1 and casting 2 has basically not changed overall.

[0167] In the above analysis, although the larger inner diameter of the loaded end has no significant effect on the maximum principal tensile stress and maximum Mises stress of the anchor cup 1, it has a certain improvement effect on the radial and annular compressive stresses of the casting 2. Specifically, the larger inner diameter of the loaded end can bring the following advantages and improvement effects:

[0168] 1 Reduce the radial compressive stress of the casting 2: The larger inner diameter of the load-bearing end helps to reduce the stress concentration inside the anchor cup 1, so that the radial compressive stress inside the anchor cup 1 can be dispersed and reduced. This helps to reduce the stress concentration of the casting 2 and improve its fatigue resistance.

[0169] 2 Improve the distribution of the circumferential compressive stress of the casting 2: A larger inner diameter of the loaded end may lead to a more uniform distribution of the force of the anchor cup 1, thereby reducing the circumferential compressive stress of the casting 2. This can reduce the stress level of the casting 2 under the ultimate bearing capacity state, and help improve the durability and stability of the anchor cup 1.

[0170] 3 Reduce stress concentration: A larger inner diameter of the loaded end can provide a wider anchoring area, which is beneficial to the uniform distribution of force between the cable and the anchor cup 1, thereby reducing the possibility of local stress concentration and helping to improve the overall fatigue resistance of the anchoring system.

[0171] In summary, a larger inner diameter of the load-bearing end has certain advantages in the design of the anchor cup 1 , which can improve the stress distribution of the casting 2 , reduce the stress concentration, and improve the fatigue resistance of the anchor cup 1 .

[0172] 5.3.2.3 Anchor cup 1 wall inclination angle

[0173] The inclination angle of the anchor cup 1 wall refers to the angle between the inside of the anchor cup 1 and the axis of the anchor cup 1, that is, when the anchor cup 1 is placed horizontally, the inclination angle of the anchor cup 1 wall refers to the angle between the inside of the anchor cup 1 and the horizontal plane, which directly affects the force transfer effect and anchoring performance between the casting 2 and the anchor cup 1. Generally, the larger the inclination angle of the anchor cup 1 wall, the more uniform the force distribution between the anchor cup 1 and the casting 2. A larger inclination angle of the anchor cup 1 wall can provide a wider anchoring area, which is conducive to the uniform distribution of force between the casting 2 and the anchor cup 1. This can reduce the possibility of local stress concentration, thereby improving the fatigue resistance of the anchoring system. However, a larger wall inclination angle will cause the structural form of the anchor cup 1 to be more unstable, and it will be easily affected by external forces and tilt or displaced. At the same time, it may cause the contact area between the anchor cup 1 and the cable to decrease, affecting the force transfer effect, thereby reducing the anchoring effect. By analyzing the stress distribution of the anchor cup 1 and the casting 2 of the combination models M9-M13 with different inclination angles of the anchor cup 1 wall at the normal serviceability limit state and the bearing capacity limit state, the influence law of the inclination angle parameter of the anchor cup 1 wall is determined.

[0174] like Fig.23 and Fig.24 As shown in the figure, the analysis of the above two groups of results shows that the maximum principal tensile stress of anchor cup 1 is located at the contact point between the small port and the end of casting 2, and gradually decreases along the length and thickness direction of anchor cup 1. In the line graph of the maximum principal tensile stress and the maximum Mises stress of anchor cup 1, along the length or thickness direction of anchor cup 1, with the change of the inclination angle, the maximum principal tensile stress and the maximum Mises stress basically do not change.

[0175] like Fig.25 As shown in the figure, the analysis of the radial and circumferential stress line graphs of casting 2 shows that in the normal use limit state, the circumferential compressive stress of casting 2 basically does not change with the change of the inclination angle, while the radial compressive stress of casting 2 first increases, then decreases, and then increases again with the increase of the inclination angle. This shows that in the normal use limit state, when the inclination angle is 7.5°-8°, the radial compressive stress of casting 2 can reach the minimum. At this time, the pressure on the steel wire 3 in casting 2 is small, which can improve the stress of anchor cup 1 to a certain extent. In the bearing capacity limit state, the circumferential compressive stress and radial compressive stress of casting 2 basically do not change. Through the analysis of the relative slip line graph of anchor cup 1 and casting 2, the relative slip of anchor cup 1 and casting 2 gradually decreases with the increase of the inclination angle. A larger inclination angle can reduce the relative slip of casting 2 and anchor cup 1 to a certain extent.

[0176] Based on the above analysis, the influence of the inclination angle on the stress and relative slip of anchor cup 1 is obtained:

[0177] 1 Analysis of principal tensile stress: The maximum principal tensile stress appears at the contact point between the small port of anchor cup 1 and the end of casting 2, and gradually decreases along the length and thickness direction of anchor cup 1. However, at different inclination angles, the changes in principal tensile stress and Mises stress are not obvious, indicating that the inclination angle has limited effect on the principal tensile stress of anchor cup 1.

[0178] 2 Analysis of radial and hoop stresses: Under the normal service limit state, the hoop compressive stress of casting 2 is basically not affected by the inclination angle, while the radial compressive stress shows a trend of first increasing, then decreasing, and then increasing again as the inclination angle increases. This shows that within a certain range, a larger inclination angle helps to reduce the radial compressive stress of casting 2.

[0179] 3 Relative slip analysis: With the increase of the inclination angle, the relative slip between the anchor cup 1 and the casting 2 gradually decreases. This means that a larger inclination angle can reduce the relative movement between the casting 2 and the anchor cup 1 to a certain extent and improve the stability of the anchor cup 1.

[0180] In summary, the effect of the inclination angle on improving the stress distribution of the anchor cup 1 is not very significant, but a larger inclination angle can reduce the relative slip between the casting 2 and the anchor cup 1 to a certain extent, which helps to improve the stability and durability of the anchor cup 1.

[0181] Relative wall thickness of front and rear ends of anchor cup 1

[0182] The front-to-back relative wall thickness of anchor cup 1 refers to the wall thickness of the free end [unstressed end] and the loaded end of anchor cup 1. The front-to-back relative wall thickness will affect the internal force distribution and stress concentration of anchor cup 1. The change of the front-to-back relative wall thickness will affect the internal stress distribution and fatigue performance of anchor cup 1. By analyzing the stress distribution of anchor cup 1 and casting 2 of combination models M14-M17 with different front-to-back relative wall thickness of anchor cup 1 at the normal service limit state and the bearing capacity limit state, the influence law of the front-to-back relative wall thickness parameters of anchor cup 1 is determined.

[0183] like Fig.26 and 27 As shown in the figure, the analysis of the above two groups of results shows that the maximum principal tensile stress of anchor cup 1 is located at the contact point between the small port and the end of casting 2, and gradually decreases along the length and thickness direction of anchor cup 1. In the line graph of the maximum principal tensile stress and the maximum Mises stress of anchor cup 1, along the length or thickness direction of anchor cup 1, with the increase of relative wall thickness (wall thickness of the loaded end), the maximum principal tensile stress and the maximum Mises stress both show a downward change, which has a significant effect on the improvement of the stress of anchor cup 1.

[0184] like Fig.28 As shown in the figure, the analysis of the radial and hoop stress line graphs of casting 2 in the above figure shows that in the normal use limit state, the hoop compressive stress and radial compressive stress of casting 2 basically do not change with the increase of the relative wall thickness of the front and rear ends. In the bearing capacity limit state, the hoop compressive stress and radial compressive stress of casting 2 decrease with the increase of the relative wall thickness (loaded end), but the overall change is not large. By analyzing the relative slip line graph of anchor cup 1 and casting 2, the relative slip of anchor cup 1 and casting 2 gradually decreases with the increase of relative wall thickness (loaded end).

[0185] In summary, the relative wall thickness has a significant effect on improving the stress of the anchor cup 1. Increasing the wall thickness at the load-bearing end can effectively reduce the stress, which can not only improve the fatigue performance, but also reduce the radial pressure on the steel wire 3, thereby improving the overall performance of the anchor cup 1.

[0186] Average wall thickness of anchor cup 1: The average wall thickness of the front and rear ends of anchor cup 1 refers to the average value of the wall thickness of the front and rear ends of anchor cup 1. Generally, a larger wall thickness can reduce the stress level when subjected to force and increase its service life. The following figures show the stress and displacement analysis of anchor cup 1 components under different average wall thickness parameters of the anchor components. By analyzing the stress distribution of anchor cup 1 and casting 2 of combination models M18-M21 with different average wall thicknesses of the front and rear ends of anchor cup 1 at the normal use limit state and the bearing capacity limit state, the influence law of the average wall thickness parameters of the front and rear ends of anchor cup 1 is determined.

[0187] like Fig.29and 30 As shown in the figure, the analysis of the above two groups of results shows that with the increase of the average wall thickness of the front and rear ends of the anchor cup 1, the principal tensile stress and Mises stress of the anchor cup 1 are significantly reduced. Fig.36 The analysis of the radial and hoop stress line graphs of casting 2 shows that, in the normal service limit state, the hoop compressive stress and radial compressive stress of casting 2 basically do not change with the increase of the average wall thickness at the front and rear ends of anchor cup 1. In the bearing capacity limit state, the hoop compressive stress and radial compressive stress of casting 2 do not change much as a whole with the increase of relative wall thickness (loaded end). Through the analysis of the relative slip line graph of anchor cup 1 and casting 2, the relative slip of anchor cup 1 and casting 2 gradually decreases with the increase of relative wall thickness (loaded end).

[0188] In summary, the average wall thickness also has a significant effect on improving the stress of the anchor cup 1. By increasing the wall thickness of the load-bearing end, the stress can be effectively reduced, which can not only improve the fatigue performance, but also reduce the radial pressure on the steel wire 3.

[0189] Friction coefficient: The friction coefficient refers to the friction coefficient of the contact surface between the anchor cup 1 and the casting 2. The friction coefficient of the contact surface between the anchor cup 1 and the casting 2 has an important influence on the stress distribution of the anchor cup 1 and the casting 2. The friction coefficient on the contact surface between the anchor cup 1 and the casting 2 determines the difficulty of relative displacement between them, which in turn affects the force and stress distribution.

[0190] Figure 31-34 The stress and displacement analysis of the anchor cup 1 component under different friction coefficient conditions are given respectively. By analyzing the stress distribution of the anchor cup 1 and the casting 2 of the combination models M22-M25 with different friction coefficients of the contact surface between the anchor cup 1 and the casting 2 at the normal service limit state and the bearing capacity limit state, the influence law of the friction coefficient parameters of the contact surface between the anchor cup 1 and the casting 2 is determined.

[0191] like Figure 37-38 As shown in the figure, the analysis of the above two groups of results shows that with the increase of the friction coefficient of anchor cup 1, the principal tensile stress of anchor cup 1 has a significant decrease; in the early stage of Mises stress of anchor cup 1, the principal tensile stress has a significant downward trend, and with the further increase of the friction coefficient of anchor cup 1, the principal tensile stress has basically no change.

[0192] right Fig.34The analysis of the radial and hoop stress line graphs of casting 2 shows that in the normal use limit state, the hoop compressive stress of casting 2 basically does not change, but the radial compressive stress gradually decreases with the increase of the friction coefficient of anchor cup 1. In the bearing capacity limit state, the hoop compressive stress of casting 2 does not change much overall, and the radial compressive stress shows a significant decrease with the increase of the friction coefficient of anchor cup 1. Through the analysis of the relative slip line graph of anchor cup 1 and casting 2, the relative slip of anchor cup 1 and casting 2 gradually decreases with the increase of the friction coefficient of anchor cup 1.

[0193] In summary, the friction coefficient between the anchor cup 1 and the casting 2 has a significant effect on improving the stress of the anchor cup 1. By adjusting the friction coefficient between the anchor cup 1 and the casting 2, the stress distribution of the anchor cup 1 can be improved. This has a good effect on improving the principal tensile stress of the anchor cup 1, helps to improve the fatigue resistance of the anchor cup 1, and prolongs its service life.

[0194] Anchor cavity structure: In the multi-level structure of the anchor cavity, the internal wall thickness of the anchor cavity will produce a stepped multi-level structure as the depth or position changes.

[0195] Figure 35-38 The stress and displacement analysis of the anchor cup 1 and casting 2 components under the conditions of the forward multi-level structure of the anchor cavity and the reverse multi-level structure of the anchor cavity are given respectively. By analyzing the stress distribution of the anchor cup 1 and casting 2 of the combination model M26-M27 with different anchor cup 1 anchor cavity structures at the normal service limit state and the bearing capacity limit state, the influence of the anchor cup 1 anchor cavity structure parameters is determined.

[0196] Depend on Figure 35-37 It can be seen that the longitudinal principal tensile stress of the anchor cavity forward multi-level structure is significantly lower than that of the smooth anchor cavity and the anchor cavity reverse multi-level structure. However, at the longitudinal relative position of 0.2, the longitudinal principal tensile stress of the anchor cavity forward multi-level structure has a very significant peak. In the thickness direction, compared with the smooth anchor cavity and the anchor cavity reverse multi-level structure, the principal tensile stress of the anchor cup 1 in the anchor cavity forward multi-level structure is significantly reduced; however, the Mises stress of the anchor cavity forward multi-level structure is slightly higher than that of the smooth anchor cavity and the anchor cavity reverse multi-level structure at the tensile end of the anchor cup 1. As the relative position increases, the Mises stress gradually decreases until it is lower than that of the sliding anchor cavity and the anchor cavity reverse multi-level structure.

[0197] right Fig.38The analysis of the radial and hoop stress line graphs of casting 2 in the figure shows that in the normal service limit state, the hoop compressive stress and radial compressive stress of casting 2 decrease at the end point of the positive multi-stage structure of the anchor cavity, increase significantly at the step of the positive multi-stage structure of the anchor cavity, and gradually decrease, while the hoop compressive stress and radial compressive stress of the reverse multi-stage structure of the anchor cavity basically remain unchanged. In the ultimate bearing capacity state, the hoop compressive stress and radial compressive stress of casting 2 at the port of the positive multi-stage structure of the anchor cavity decrease slightly, and the hoop compressive stress and radial compressive stress at the step increase significantly. At the end point of the reverse multi-stage structure of the anchor cavity, the hoop compressive stress decreases slightly, while the radial compressive stress increases significantly. Through the analysis of the relative slip line graph of anchor cup 1 and casting 2, the relative slip of anchor cup 1 and casting 2 decreases in both the positive multi-stage structure of the anchor cavity and the reverse multi-stage structure of the anchor cavity, and the relative slip of the positive multi-stage structure of the anchor cavity is smaller.

[0198] In summary, the positive multi-level structure of the anchor cavity has a significant effect on improving the stress of the anchor cup 1. The positive multi-level structure of the anchor cavity makes the stress peak away from the small port, which helps to improve the radial pressure of the steel wire 3. By adding the positive multi-level structure of the anchor cavity, the stress of the anchor cup 1 is significantly improved. The reverse multi-level structure does not improve the stress level. It mainly improves the main tensile stress, which helps to improve the fatigue resistance of the anchor cup 1. However, more attention needs to be paid to the main compressive stress in the reverse multi-level structure.

[0199] Chamfering the inner wall of the anchor cup 1: Chamfering the inner wall of the anchor cup 1 refers to a processing method in which an oblique cutting is performed on the edge or corner of the inner wall of the anchor cup 1 to form a chamfer. Chamfering the inner wall of the anchor cup 1 can alleviate the stress concentration phenomenon to a certain extent and improve the structural continuity of the anchor cup 1.

[0200] Fig.39 and 40 The stress and displacement analysis of anchor cup 1 and casting 2 are given respectively when the inner wall of anchor cup 1 is chamfered. Benchmark is a structure without chamfer of the inner wall of anchor cup 1, and M29 is a structure with chamfer of the inner wall of anchor cup 1. By analyzing the stress distribution of anchor cup 1 and casting 2 of the combined model M29 with chamfer at the serviceability limit state and bearing capacity limit state, the influence of chamfer parameters is determined.

[0201] like Fig.39 and 40 As shown in the figure, the analysis of the two groups of results shows that under the normal service limit state and the bearing capacity limit state, whether the anchor cup 1 has an inner wall chamfer has little effect on the longitudinal principal tensile stress of the anchor cup 1 and the Mises stress of the anchor cup 1. In the thickness direction, whether the anchor cup 1 has an inner wall chamfer has little effect on the principal tensile stress of the anchor cup 1, but the inner wall chamfer of the anchor cup 1 can slightly reduce the concentration of the Mises stress of the anchor cup 1 at the stress port of the anchor cup 1.

[0202] right Fig.41 The analysis of the radial and hoop stress line graphs of casting 2 shows that in the normal service limit state, the hoop compressive stress and radial compressive stress of casting 2 increase with the presence of chamfers. In the bearing capacity limit state, the hoop compressive stress and radial compressive stress of casting 2 increase with the presence of chamfers. Through the analysis of the relative slip line graph of anchor cup 1 and casting 2, the relative slip between anchor cup 1 and casting 2 basically does not change with the presence of chamfers.

[0203] In summary, the chamfering of the inner wall of the anchor cup 1 can alleviate the stress concentration phenomenon of the anchor cup 1 to a certain extent, improve the structural continuity of the anchor cup 1, and thus improve the reliability and service life of the anchor cup 1, but this improvement effect is not obvious.

[0204] Summary: Through the above parametric modeling analysis, the influence of various parameters on the mechanical properties of anchor cup 1 was obtained. The following table summarizes the influence characteristics of each parameter.

[0205] Table 2: Summary of parameter influence rules

[0206]

[0207] Optimization structure of anchor cup 1: Based on the finite element analysis results of the above parameters such as anchoring length, inner diameter of the loaded end, inner inclination angle, front and rear relative wall thickness, average wall thickness, friction coefficient, anchor cavity structure, and chamfer of the inner wall of anchor cup 1, the following optimization suggestions are put forward for the parameters of anchor cup 1.

[0208] Table 3 Anchor cup 1 parameter optimization suggestions

[0209]

[0210] Fig.12 and 13 The stress-displacement analysis of anchor cup 1 and casting 2 after parameter optimization is given respectively. The stress distribution of anchor cup 1 of the optimized combined model M28 at the serviceability limit state and bearing capacity limit state is analyzed respectively.

[0211] Through Fig.12 and 13 The results of the two groups of research and analysis show that under the normal service limit state and the bearing capacity limit state, the principal tensile stress and Mises stress of the optimized model anchor cup 1 in both the longitudinal and thickness directions are significantly reduced. The maximum principal tensile stress and maximum Mises stress of anchor cup 1 are also improved.

[0212] right Fig.14The analysis of the radial and hoop stress line graphs of casting 2 in the figure shows that the hoop compressive stress and radial compressive stress of casting 2 are reduced with the optimization of anchor cup 1 at the service limit state and the bearing capacity limit state. The analysis of the relative slip line graph of anchor cup 1 and casting 2 shows that the relative slip between anchor cup 1 and casting 2 is reduced with the optimization of anchor cup 1.

[0213] In summary, by increasing the wall thickness, increasing the friction coefficient, and changing the anchor cavity structure to a positive multi-stage structure, the maximum principal compressive stress of the optimized anchor cup 1 becomes larger, and the position of the maximum principal compressive stress will move away from the loaded end, which improves the radial pressure at the loaded port and optimizes the performance of the anchor cup 1 to a great extent.

[0214] In order to further evaluate the improvement effect of the optimized model and the initial model design in fatigue resistance, the stress amplitude was used for evaluation and analysis. According to literature research, the steps of evaluating fatigue performance using stress amplitude are to apply the load corresponding to the maximum stress (peak value) to the steel wire 3 to obtain the stress distribution of the system, and then apply the load corresponding to the minimum stress (valley value) to the steel wire 3 to obtain the stress distribution of the system, and extract the stress difference to obtain the stress amplitude of each component. According to experience, the maximum stress applied by the steel wire 3 is 0.45 times the stress intensity, and the minimum stress is the maximum stress minus 280MPa. Based on this, combined with the strength of the steel wire 3, the maximum load of 780kN and the minimum load of 560kN were applied to the model before optimization and the model after optimization, respectively, and the stress distribution of the anchor cup 1 system was obtained by finite element analysis.

[0215] like Fig.11 Figure a shows the comparison of the stress valley and peak values ​​of anchor cup 1 before and after optimization. It can be seen that the stress amplitude of anchor cup 1 slightly increased after optimization, from 30.6MPa to 35.6MPa. On the one hand, the stress amplitude is small and has little effect on the fatigue of anchor cup 1. On the other hand, the ratio of the stress valley to the peak value after optimization is reduced. According to literature research, if the stress amplitude is close at a low stress ratio level, the fatigue strength of anchor cup 1 with a low stress ratio is relatively higher. Therefore, it can be determined that the fatigue resistance of anchor cup 1 is improved after optimization. Fig.11 Figure b shows the change in the compressive stress amplitude of the casting 2 before and after optimization. It can be seen that the compressive stress amplitude of the casting 2 before optimization is 141MPa, while the compressive stress amplitude is reduced to 109.2MPa after optimization. Since the compressive stress of the casting 2 directly acts on the steel wire 3, and the tensile stress amplitude of the steel wire 3 is unchanged before and after optimization, the comprehensive stress amplitude of the steel wire 3 is improved. Through the change in the compressive stress of the casting 2, it can be qualitatively determined that the fatigue resistance of the steel wire 3 is also improved.

[0216] In summary, through further analysis of the anchor cup 1 structure, it can be seen that the fatigue resistance of the optimized anchor cup 1 structure and anchoring system has been improved.

[0217] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A new type of cable anchoring system, characterized in that: It comprises an anchor cup (1), wherein: The anchor cup (1) is provided with a through main anchor cavity (6), so that one end of the main anchor cavity (6) has a front end hole (7) and the other end has a rear end hole (8); The inner wall of the main anchor cavity (6) is provided with at least two secondary truncated cone surfaces (10) in sequence along the through direction of the main anchor cavity (6), so that the main anchor cavity (6) forms at least two truncated cone anchor cavities (11), and a step transition surface (15) is provided between adjacent secondary truncated cone surfaces (10); In the direction from the front end hole (7) to the rear end hole (8), the inner diameter of the secondary truncated cone surface (10) and the inner diameter of the step transition surface (15) both increase.

2. A new cable anchoring system according to claim 1, characterized in that: In the through direction along the main anchor cavity (6), the length of the secondary frustum surface (10) is greater than the length of the adjacent step transition surface (15).

3. A new cable anchoring system according to claim 1, characterized in that: The secondary frustum surface (10) continuously transitions to the adjacent step transition surface (15).

4. A new cable anchoring system according to claim 1, characterized in that: In the direction from the front end hole (7) to the rear end hole (8): The inner diameter of the secondary frustum surface (10) gradually increases. and / or, The inner diameter of the step transition surface (15) gradually increases.

5. A new cable anchoring system according to claim 1, characterized in that: At least two adjacent secondary frustum surfaces (10) are parallel.

6. A new cable anchoring system according to claim 1, characterized in that: The secondary frustum surface (10) is provided with roughness.

7. A new cable anchoring system according to claim 1, characterized in that: The secondary frustum surface (10) is provided with pits (12) and / or protrusions (13).

8. A new cable anchoring system according to claim 1, characterized in that: The cross-sectional line of the secondary frustum surface along the axial direction is a straight line, a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a clothoid curve.

9. A new cable anchoring system according to claim 1, characterized in that: A first protrusion (17) is provided on the step transition surface (15).

10. A new cable anchoring system according to claim 1, characterized in that: An inner recess (16) is provided on the step transition surface (15), and the bottom of the inner recess (16) is inclined toward the front end hole (7).

11. A new cable anchoring system according to claim 1, characterized in that: It also includes a steel wire strand (14), the main anchor cavity (6) is filled with a casting (2), the casting (2) is in contact with the secondary truncated cone surface (10) and the step transition surface (15), the steel wire strand (14) passes through the front end hole (7), and at least a part of the steel wire strand (14) is located in the casting (2).

12. A new cable anchoring system according to claim 11, characterized in that: A wire guide sleeve (20) is also provided in the main anchor cavity (6), the wire rope strand (14) passes through the wire guide sleeve (20), and the portion of the wire rope strand (14) between the wire guide sleeve (20) and the rear end hole (8) is arranged to be wire-split and form at least three strands of wire (3), the inner wall (19) of the wire guide sleeve (20) has a curvature that continuously changes along the opening direction of the wire guide sleeve (20), the portion of the inner wall (19) of the wire guide sleeve (20) close to the front end hole (7) is smoothly tangent to the outer wall of the corresponding portion of the wire rope strand (14), and the portion of the inner wall (19) of the wire guide sleeve (20) close to the rear end hole (8) is smoothly tangent to the outermost layer of wire (3) of the wire rope strand (14) after the wire rope strand (14) is split.

13. A new cable anchoring system according to claim 12, characterized in that: The steel wire guide sleeve (20) is arranged in a trumpet shape.

14. A new cable anchoring system according to claim 12, characterized in that: In the cross-sectional direction of the wire guide sleeve (20), the inner wall (19) of the wire guide sleeve (20) is in the shape of a regular polygon.

15. A new cable anchoring system according to claim 12, characterized in that: Along the opening direction of the wire guide sleeve (20), the cross-sectional line of the inner surface of the wire guide sleeve (20) includes a circular curve, an elliptical curve, a power function curve, an exponential function curve, a hyperbola or a clothoid curve.

16. A new cable anchoring system according to claim 1, characterized in that: Along the direction from the free end to the load-bearing end of the anchor cup (1), the wall thickness of the anchor cup (1) gradually increases.

17. A new cable anchoring system according to claim 1, characterized in that: The diameter of the rear end hole (8) is larger than the diameter of the front end hole (7).

18. A new cable anchoring system according to any one of claims 1 to 17, characterized in that: The anchor cup (1) can be used for a main cable, a sling or a stay cable.

19. A design method for a new cable anchoring system according to any one of claims 1 to 18, characterized in that: The following steps are involved: S1. Determine the position of the main anchor cavity surface (9) based on the diameter of the front end hole (7) and the diameter of the rear end hole (8); S2. Determine the length of each secondary frustum surface (10); S3. Determine the end position of the secondary truncated cone surface (10) close to the front end hole (7) based on the length of the secondary truncated cone surface (10) and the position of the main anchor cavity surface (9); S4. Determine the angle of the secondary frustum surface (10) relative to the main anchor cavity surface (9); S5. Determine the angle of the step transition surface (15) relative to the secondary frustoconical surface (10) based on the angle of the secondary frustoconical surface (10) relative to the main anchor cavity surface (9).

20. A design method for a new cable anchoring system according to any one of claims 1 to 18, characterized in that: The following steps are involved: A1. Analyze the influence of stress distribution results of the cable anchorage system benchmark model on the performance of the anchor cup (1) and the casting (2); A2. Combining the key parameters of the anchor cup (1) to form multiple combination models; A3. Based on each combined model, at least some of the key parameters are analyzed to determine the stress distribution and stress peak of the anchor cup (1) and the casting (2), and determine the influence of the key parameters; A4. Optimizing the anchor cup (1), casting (2) and steel wire (3) based on the influence rules of each key parameter to form a model of the new cable anchoring system; A5. Evaluate and analyze the improvement effect of the novel cable anchoring system model and the cable anchoring system benchmark model in terms of fatigue resistance.

21. The design method according to claim 20, characterized in that: The key parameters of the anchor cup (1) include anchoring length, anchor cup (1) diameter, anchor cup (1) wall inclination angle, relative wall thickness at the front and rear ends of the anchor cup (1), average wall thickness of the anchor cup (1), friction coefficient between the casting and the anchor cup (1), anchor cavity structure and anchor cup (1) inner wall chamfer.

22. The design method according to claim 21, characterized in that: In step A2, the key parameters of the anchor cup (1) are combined as follows: 。 23. The design method according to claim 20, characterized in that: Step A3 is specifically as follows: By analyzing the stress distribution and stress peak of the anchor cup (1) and the casting (2) of the combination models M1-M4 with different anchoring lengths at the serviceability limit state and the bearing capacity limit state, the influence law of the anchoring length parameter is determined; By analyzing the stress distribution and stress peak of the anchor cup (1) and the casting (2) of the combination models M5-M8 with different inner diameters of the loaded end at the normal service limit state and the bearing capacity limit state, the influence law of the inner diameter parameter of the loaded end is determined; By analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination models M9-M13 with different inclination angles of the anchor cup (1) wall at the normal service limit state and the bearing capacity limit state, the influence law of the inclination angle parameter of the anchor cup (1) wall is determined; by analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination models M14-M17 with different relative wall thicknesses of the front and rear ends of the anchor cup (1) at the normal service limit state and the bearing capacity limit state, the influence law of the relative wall thickness parameter of the front and rear ends of the anchor cup (1) is determined; By analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination models M18-M21 with different average wall thicknesses at the front and rear ends of the anchor cup (1) at the normal service limit state and the bearing capacity limit state, the influence law of the average wall thickness parameters at the front and rear ends of the anchor cup (1) is determined; By analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination models M22-M25 with different friction coefficients of the contact surface between the anchor cup (1) and the casting (2) at the normal service limit state and the bearing capacity limit state, the influence law of the friction coefficient parameters of the contact surface between the anchor cup (1) and the casting (2) is determined; By analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination models M26-M27 with different anchor cup (1) anchor cavity structures at the normal service limit state and the bearing capacity limit state, the influence law of the anchor cup (1) anchor cavity structure parameters is determined; by analyzing the stress distribution of the anchor cup (1) and the casting (2) of the combination model M29 with chamfers at the normal service limit state and the bearing capacity limit state, the influence law of the chamfer parameters is determined.

24. The design method according to claim 23, characterized in that: The key parameters influence the following rules: 。

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