Large-span cable-stayed suspension bridge uses on-site large adjustment amount of sling pin hinge type anchor device

Abstract

The application relates to a large-adjustment on-site sling pin hinge type anchor for an ultra-large-span cable-stayed suspension bridge and belongs to the technical field of bridges. The anchor cup is arranged above the fork-shaped lug plate, the sling is anchored in the anchor cup, the length adjustment assembly is connected between the fork-shaped lug plate and the anchor cup, the length adjustment assembly adjusts the distance between the anchor cup and the fork-shaped lug plate, and then the length of the sling is adjusted; the steel beam fork lug is arranged on the bottom of the fork-shaped lug plate, the angle adjustment assembly is connected between the fork-shaped lug plate and the steel beam fork lug; the angle adjustment assembly adjusts the rotation angle and the inclination angle of the fork-shaped lug plate. The cooperation between the adjusting screw, the adjusting sleeve and the fork-shaped lug plate can be adjusted in a large range on site, and the length requirement of the sling is met. The centripetal joint bearing can meet the adjustment of the in-bridge direction angle and the cross-bridge direction angle of the sling, and the service life of the component is prolonged.

Description

Technical Field

[0001] This invention relates to a large-scale adjustable cable-stayed-suspension bridge anchorage with on-site adjustment capacity, belonging to the field of bridge technology. Background Technology

[0002] To achieve ultra-long spans in bridge systems, the cable-stayed-suspension hybrid system presents a highly attractive alternative. By transferring the load from the suspenders to the main cables of a suspension bridge, the bridge deck in the cable-stayed-suspension hybrid system is also supported by the stay cables. Therefore, the tension in the main cables is significantly reduced compared to a suspension bridge of the same span. During bridge erection, the cantilever is effectively shortened, thereby improving the bridge's wind stability during construction. Furthermore, for suspension bridges of the same span, the combined bridge system reduces the overall project cost due to the effective reduction in the cost of the main cables and large anchorages. The increased main span eliminates the difficulties of construction in water, enabling construction even in soft soil conditions. The shortened cable-stayed section of the bridge reduces axial forces on the bridge deck, stay cable length, and tower height, improving its economic efficiency.

[0003] To mitigate adverse stress conditions on the main girder during construction, temporary hangers and highly adjustable slings are installed in the transition zone between the cable-stayed and suspension sections. During the hoisting of the central suspension section, the internal forces of the slings and the main girder are improved by adjusting the internal forces of the temporary hangers and the anchorages at the sling beam ends. Anchorage structures with adjustable lengths (generally not less than 500mm) are required at the sling beam ends. A conventional pin-hinged anchorage structure is shown below. Figure 1 As shown, the conventional pin-hinged suspender cable has a single-end adjustment length of 20mm, and this adjustment can only be achieved in the workshop by rotating the two forks at both ends, through the internal threads between the forks and the anchor cups. However, on-site adjustment is not possible, failing to meet the requirement of an adjustment length of 500mm. Furthermore, the lack of a traditional cable end angle adjustment mechanism leads to excessive bending moments at the cable ends of suspension bridges caused by vehicle loads and wind loads, resulting in the breakage of components such as connecting lugs. To address these issues, a pin-hinged anchorage with a large on-site adjustment range for ultra-long span cable-stayed suspension bridges is proposed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a large-scale on-site adjustable cable pin-hing anchor for ultra-long span cable-stayed-suspension bridges, which can make extensive adjustments to the cable length on-site to meet the cable length requirements, and can also meet the adjustment of the cable angle along the bridge direction and the transverse bridge direction.

[0005] The technical solution adopted by this invention to solve the above problems is as follows: a large-span cable-stayed-suspension bridge on-site adjustable cable-stayed pin-hinged anchorage, including a forked lug plate, an anchor cup above the forked lug plate, and a cable anchored in the anchor cup. The forked lug plate and the anchor cup are connected by a length adjustment component, which adjusts the distance between the anchor cup and the forked lug plate, thereby adjusting the length of the cable. A steel beam fork lug is provided across the bottom of the forked lug plate, and the forked lug plate and the steel beam fork lug are connected by an angle adjustment component. The angle adjustment component adjusts the rotation angle and tilt angle of the forked lug plate.

[0006] The length adjustment assembly includes an adjustment sleeve and an adjustment screw. A first internally threaded hole is vertically arranged at the top of the fork-shaped lug. The adjustment sleeve is positioned above the fork-shaped lug. An adjustment screw is located between the fork-shaped lug and the adjustment sleeve, with its threaded section screwed into the first internally threaded hole. The head of the adjustment screw passes through the bottom of the adjustment sleeve and is located within the adjustment sleeve. An anchor cup has an anchor cup threaded section on its outer surface. The adjustment sleeve has a second internally threaded hole at its center. The anchor cup is located within the adjustment sleeve, and the two are threadedly connected. Rotating the adjustment sleeve causes the anchor cup to move within the adjustment sleeve.

[0007] The adjusting screw and the first internal threaded hole are connected by a triangular thread, which achieves self-locking between them.

[0008] The first internal thread hole on the fork-shaped lug has a wedge-shaped inclined surface at the bottom of the internal thread, and the inclination angle of the wedge-shaped inclined surface is 28-32°.

[0009] The adjusting screw is a T-shaped screw, and the adjusting sleeve has a screw hole at the bottom. The head of the adjusting screw is a square head, and the size of the square head is larger than the diameter of the screw hole. The adjusting screw passes through the screw hole through the second internal thread hole and is then screwed into the first internal thread hole, so that the square head of the adjusting screw is confined within the adjusting sleeve.

[0010] The adjustable length range of the sling is greater than 500mm.

[0011] The angle adjustment assembly includes a radial joint bearing and a pin. The radial joint bearing is disposed inside the steel beam fork lug. The pin passes through the inner ring of the radial joint bearing. Both ends of the pin pass through the pin holes on both sides of the fork-shaped lug, so that the fork-shaped lug is connected to the radial joint bearing and the steel beam fork lug. The inner ring of the radial joint bearing rotates and tilts, which drives the pin and the fork-shaped lug to rotate and tilt.

[0012] The rotation angle of the angle adjustment component is 0°~30°, and the tilt angle is 0°~15°. Both the fork-shaped lugs and the anchor cups are made of ultra-high strength steel.

[0013] Compared with existing technologies, the advantages of this invention are as follows: A large-range adjustable cable-stayed suspension bridge anchorage with pin hinge design allows for on-site adjustment of the cable length over a wide range, meeting cable length requirements, through the cooperation of the adjusting screw, adjusting sleeve, and fork-shaped lug. The radial joint bearing allows for adjustment of the cable's longitudinal and transverse angles, improving the service life of the component. Attached Figure Description

[0014] Figure 1 This is a simplified diagram of a conventional pin-hinged anchorage structure. Figure 2 This is a schematic diagram of a large-span cable-stayed-suspension bridge with a large on-site adjustable cable pin hinge anchorage according to an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the shortest length of a large-span cable-stayed-suspension bridge with a large on-site adjustable suspension cable pin hinge anchorage according to an embodiment of the present invention. Figure 4 This is a schematic diagram showing the longest length of a large-span cable-stayed-suspension bridge on-site adjustable cable-stayed pin-hinged anchorage according to an embodiment of the present invention; Figure 5 A cross-sectional view of the threaded connection between the adjusting ear plate and the adjusting screw; Figure 6 This is a schematic diagram of a radial joint bearing; Figure 7 This is a schematic diagram of the rotation of the inner ring of a radial joint bearing. Figure 8 A schematic diagram showing the tilt of the inner ring of a radial joint bearing; Figure 9 Schematic diagram for adjusting the angle of the suspension cable along the bridge direction; Figure 10 This is a schematic diagram of the lateral angle adjustment of the suspension cable bridge. Figure 11 Dimensional diagrams for on-site adjustable cable-stayed / suspension bridge anchorages with large spans; Figure 12 A schematic diagram for adjusting the ear plate; Figure 13 This is a schematic diagram of the adjusting sleeve and the adjusting screw; In the diagram: 1. Suspension cable body; 2. Anchor cup; 3. Adjusting sleeve; 4. Adjusting screw; 5. Fork-shaped lug; 6. Pin shaft; 7. Steel beam fork lug; 8. Radial joint bearing. Detailed Implementation

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0016] like Figure 2As shown in this embodiment, a large-span cable-stayed suspension bridge with a large on-site adjustable cable-stayed pin-hinged anchorage includes a fork-shaped lug 5. A first internally threaded hole is vertically arranged at the top of the fork-shaped lug 5. An adjusting sleeve 3 is located above the fork-shaped lug 5. A vertically arranged adjusting screw 4 is located between the fork-shaped lug 5 and the adjusting sleeve 3. The threaded section of the adjusting screw 4 is screwed into the first internally threaded hole. The head of the adjusting screw 4 passes through the bottom of the adjusting sleeve, so that the head of the adjusting screw is located in the adjusting sleeve, connecting the fork-shaped lug 5 and the adjusting sleeve. The adjusting sleeve 3 has a second internally threaded hole at its center. An externally threaded section of the anchor cup 2 is provided on the outer surface of the anchor cup. The anchor cup is located inside the adjusting sleeve and is threadedly connected to the adjusting sleeve. The cable body 1 is anchored inside the anchor cup. Rotating the adjusting sleeve 3 causes the anchor cup to move within the adjusting sleeve, thereby adjusting the cable length. A steel beam fork lug 7 spans the bottom of the fork-shaped lug. A radial spherical plain bearing 8 is installed inside the steel beam fork lug 7. A pin 6 passes through the inner ring of the radial spherical plain bearing. The two ends of the pin pass through the pin holes on both sides of the fork-shaped lug, thereby connecting the fork-shaped lug with the radial spherical plain bearing and the steel beam fork lug. Figure 9 , 10 As shown, the rotational and tilting oscillations of the radial joint bearing drive the pin and fork-shaped lug to rotate and tilt, thereby adjusting the longitudinal and transverse angles of the suspension cable.

[0017] The adjusting screw is a T-shaped screw, and a screw hole is opened at the bottom of the adjusting sleeve. The head of the adjusting screw is a square head, and the size of the square head is larger than the diameter of the screw hole. The adjusting screw passes through the screw hole through the second internal thread hole and is then screwed into the first internal thread hole, so that the square head of the adjusting screw is confined inside the adjusting sleeve.

[0018] like Figure 3 , 4 As shown, when the adjusting sleeve is rotated so that the bottom of the anchor cup is close to and supported by the head of the adjusting screw, the sling length is at its shortest; when the adjusting sleeve is rotated so that the bottom of the anchor cup is far away from the head of the adjusting screw and the bottom of the anchor cup is located at the top of the adjusting sleeve, the sling length is at its longest; the sling adjustment length range is greater than 500mm.

[0019] The outer ring of the radial spherical plain bearing and the steel beam fork lug adopt an interference fit or a transition fit, with a tolerance fit grade of H7. The surface roughness of the bearing bore of the steel beam fork lug is not greater than 3.2μm. The inner ring of the radial spherical plain bearing and the pin are connected by a transition fit, with a tolerance fit grade of h6~g6. The surface roughness of the inner ring of the angular radial spherical plain bearing is not greater than 3.2μm.

[0020] The motion path of the above-mentioned radial joint bearing is as follows Figure 7 , 8 As shown, point W(R, ε, θ) is a contact point on the inner ring of the contact surface, ε and θ are the original (initial) position angles of that point, and d kIt refers to the inner and outer sphere radii, where the sphere radius R = d. k / 2 (unit: mm). The tilting oscillation angle is β0, which ranges from 0° to 15°; the rotational oscillation angle is α0, which ranges from 0° to 30°, and the maximum rotational oscillation angle is α0. 0max α 0max With a maximum angle of 30°, it can achieve a wide range of angle adjustments from 0° to 30° along the bridge direction and from 0° to 15° in the transverse direction.

[0021] like Figure 5 As shown, the T-shaped screw and the fork-shaped lug are connected by a triangular thread with good self-locking performance to prevent loosening between the first internal thread hole of the T-shaped screw and the fork-shaped lug during long-term service of the sling. Based on this, a 30° wedge-shaped bevel is machined at the root of the internal thread of the first internal thread hole of the fork-shaped lug. When the external thread section of the T-shaped screw is tightened with the first internal thread hole of the fork-shaped lug, the tip of the external thread of the T-shaped screw presses firmly against the wedge-shaped bevel, thus generating a large locking force. Due to the change in the thread angle, the normal force generated by the contact between the threads forms an angle of approximately 60° with the axis of the T-shaped screw, instead of the 30° angle of ordinary threads. Under the same cable force F0, the normal force F on the bearing side tooth of the fork-shaped lug... n =F0 / cos60°=2F0, which is greater than the normal force F of the internal thread of a standard fork-shaped lug. n =F0 / cos30°=1.154F0, therefore the frictional torque is large; the radial load F of the internal thread of the first internal thread hole of the fork-shaped lug plate. r Greater than axial load F a Furthermore, the symmetrical distribution ensures that the internal thread of the first internal threaded hole on the fork-shaped lug is not easily loosened between the thread and the T-shaped screw, effectively resisting lateral vibration and thus greatly improving the anti-loosening capability. This inevitably strengthens the anti-loosening force F on the normal force of the internal thread of the first internal threaded hole. n The force is applied to the top of the T-shaped screw thread, where the thread has high flexibility and is easily deformed. This allows for more even force distribution among the threads, increasing the number of threads that can bear the load compared to ordinary fork-shaped lug internal threads, thus improving load-bearing capacity and service life. Simultaneously, the internal thread of the first internal threaded hole makes line contact with the T-shaped screw along the thread, eliminating radial clearance caused by relative movement between the internal and external threads under lateral dynamic loads, thereby preventing the fork-shaped lug from automatically disengaging from the adjusting screw.

[0022] like Figure 6 As shown in Table 1, the structural dimensions of the radial spherical bearing are as follows.

[0023] Table 1

[0024] like Figure 11As shown in Table 2, the structural dimensions of the adjusting sleeve and anchor cup are shown in Table 3, the structural dimensions of the T-shaped screw are shown in Table 4, and the structural dimensions of the fork-shaped lug are shown in Table 5.

[0025] Table 2

[0026] Table 3

[0027] Table 4

[0028] like Figure 12 As shown, the connection structure of the fork-shaped lug and the pin is verified: (1) Dimensional requirements for fork-shaped ear plates ; In the formula: b is the net distance between the two sides of the fork-shaped ear plate and the edge of the pin hole; t is the thickness of the fork-shaped lug; 'a' represents the axial force direction of the sling, and the minimum distance between the pin hole edge and the plate edge. b e This is the equivalent distance between the two sides of the fork-shaped lug and the edge of the pin hole.

[0029] (2) The strength at the net cross-section of the pin hole shall meet the following requirements. Tensile strength at the net cross-section of the pin hole: ; Tensile (split) strength of the end section of the fork-shaped lug: ; Shear strength of fork-shaped lugs: ; In the formula: T is the axial tension of the sling; b1 is the calculated width at the fork lug pin hole; d. Diameter of the pin hole (mm); f The allowable tensile strength of the fork-shaped lugs; Z is the width of the shear section at the end of the fork-shaped lug plate; f v The allowable shear strength for the fork-shaped lugs.

[0030] The calculation results of the fork-shaped ear plate are shown in Table 5.

[0031] Table 5

[0032] (3) The strength of the pin must meet the following requirements. The compressive strength of the pin ; Shear strength of the pin ; In the formula: d is the diameter of the pin (mm); f c b Permissible compressive strength of the pin (N / mm) 2 ); n v The number of sheared surfaces; f v b The allowable shear strength of the pin (N / mm) 2 ); The results of the pin verification are shown in Table 6.

[0033] Table 6

[0034] like Figure 13 As shown, the connection structure between the T-screw and the adjusting sleeve is verified: (1) Tensile strength verification of T-shaped screw ; In the formula: σ T Tensile stress of the T-screw (N / mm) 2 ); T represents the axial tensile load (N) on the sling.

[0035] d c The outer diameter (mm) of the T-shaped screw; [σ T [The allowable stress of the T-screw is in N / mm².] 2 ); (2) Strength verification of the adjusting sleeve ; In the formula: σ H To adjust the tensile stress (N / mm) of the sleeve 2 ); T represents the axial tensile load (N) on the sling.

[0036] D2 is the outer diameter of the adjusting sleeve (mm); D1 is the inner diameter of the adjusting sleeve (mm); [σ H [The allowable stress of the T-screw is in N / mm².]2 ); Adjusting the shear stress of the sleeve: ; In the formula: To adjust the shear stress (N / mm) of the sleeve 2 ); T represents the axial tensile load (N) on the sling.

[0037] D1 is the inner diameter of the connecting sleeve (mm); H is the height of the bottom of the sleeve (mm); [τ] is used to adjust the allowable shear stress of the sleeve. The verification results of the T-screw and adjusting sleeve are shown in Table 7.

[0038] Table 7

[0039] like Figure 6 As shown, the structural calculation of the radial spherical bearing is as follows: (1) The formula for calculating the sliding velocity of the working spherical surface of a radial spherical bearing is: v=2.9089×10 -4 ×β×d k f; In the formula: β is the rotational swing angle of the radial joint bearing, and the rotational swing angle is 12°; f is the oscillation frequency (1 / min) of the radial joint bearing, designed to oscillate once per minute; d k The equivalent diameter (mm) of the sliding spherical surface of the angular radial joint bearing. The sliding speed of a radial joint bearing must be less than its limit sliding speed.

[0040] (2) The nominal contact stress of a radial spherical bearing is calculated according to the following formula: p=150 (P / C) da ); The nominal contact stress of a radial spherical bearing must be less than the allowable contact stress.

[0041] (3) The pv value on the working surface of the radial spherical plain bearing must be limited. The pv value is calculated according to the following formula: pv=2.9089×10 -4 ×β×d k f×k(P / C) da ) The pv value of a radial spherical bearing must be less than the pv limit value of the contact pair.

[0042] Table 8 shows a comparison of the calculated sliding speed, nominal contact stress, and pv value of the radial spherical bearing with the limiting sliding speed, contact stress, and limiting pv value of the friction pair material.

[0043] Table 8

[0044] To ensure the compactness and connection reliability of this large-adjustment sling-and-hinged anchorage structure, both the fork-shaped lugs and the anchor cup are made of 42CrMo alloy structural steel. 42CrMo steel is an ultra-high-strength steel with high strength and toughness, good hardenability, no obvious temper brittleness, minimal deformation during quenching, and high fatigue limit and resistance to repeated impacts after tempering, exhibiting good low-temperature impact toughness. Its chemical composition is shown in Table 9 below, and its mechanical properties are shown in Table 10.

[0045] Table 9

[0046] Table 10 (Sample blank size is 25mm)

[0047] This application enables a wide range of on-site adjustments to the sling length through the cooperation of the adjusting screw, adjusting sleeve, and fork-shaped lug, meeting sling length requirements. The inclusion of a radial joint bearing allows for adjustments to the sling's longitudinal and transverse angles, thus improving the component's service life.

[0048] In addition to the above embodiments, the present invention also includes other embodiments. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of the present invention.

Claims

1. A large-span cable-stayed / suspension bridge with a pin-hinged anchorage for on-site adjustment, characterized by: The device includes a forked lug plate, an anchor cup above the forked lug plate, and a sling anchored inside the anchor cup. The forked lug plate and the anchor cup are connected by a length adjustment component, which adjusts the distance between the anchor cup and the forked lug plate, thereby adjusting the length of the sling. A steel beam fork lug spans the bottom of the forked lug plate, and the forked lug plate and the steel beam fork lug are connected by an angle adjustment component. The angle adjustment component adjusts the rotation angle and tilt angle of the forked lug plate.

2. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type according to claim 1, characterized in that: The length adjustment assembly includes an adjustment sleeve and an adjustment screw. A first internally threaded hole is vertically arranged at the top of the fork-shaped lug. The adjustment sleeve is positioned above the fork-shaped lug. An adjustment screw is located between the fork-shaped lug and the adjustment sleeve, with its threaded section screwed into the first internally threaded hole. The head of the adjustment screw passes through the bottom of the adjustment sleeve and is located within the adjustment sleeve. An anchor cup has an anchor cup threaded section on its outer surface. The adjustment sleeve has a second internally threaded hole at its center. The anchor cup is located within the adjustment sleeve, and the two are threadedly connected. Rotating the adjustment sleeve causes the anchor cup to move within the adjustment sleeve.

3. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 2, characterized in that: The adjusting screw and the first internal threaded hole are connected by a triangular thread, which achieves self-locking between them.

4. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 3, characterized in that: The first internal thread hole on the fork-shaped lug has a wedge-shaped inclined surface at the bottom of the internal thread, and the inclination angle of the wedge-shaped inclined surface is 28-32°.

5. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 2, characterized in that: The adjusting screw is a T-shaped screw, and the adjusting sleeve has a screw hole at the bottom. The head of the adjusting screw is a square head, and the size of the square head is larger than the diameter of the screw hole. The adjusting screw passes through the screw hole through the second internal thread hole and is then screwed into the first internal thread hole, so that the square head of the adjusting screw is confined within the adjusting sleeve.

6. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 1, characterized in that: The adjustable length range of the sling is greater than 500mm.

7. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 1, characterized in that: The angle adjustment assembly includes a radial joint bearing and a pin. The radial joint bearing is disposed inside the steel beam fork lug. The pin passes through the inner ring of the radial joint bearing. Both ends of the pin pass through the pin holes on both sides of the fork-shaped lug, so that the fork-shaped lug is connected to the radial joint bearing and the steel beam fork lug. The inner ring of the radial joint bearing rotates and tilts, which drives the pin and the fork-shaped lug to rotate and tilt.

8. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 7, characterized in that: The rotation angle of the angle adjustment component is 0°~30°, and the tilt angle is 0°~15°.

9. The on-site large-adjustment cable-stayed / suspension bridge anchorage with pin hinge type as described in claim 1, characterized in that: Both the fork-shaped lugs and the anchor cups are made of ultra-high strength steel.

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