Flexible collision damping device and system applied to suspension bridge sling
Technical Field
The utility model relates to an engineering structure damping technical field, concretely relates to be applied to flexible collision damping device and system of suspension bridge hoist cable.
Background
The suspension rod cables of the large-span suspension bridge are all steel wire ropes with large slenderness ratio and high strength, have the characteristics of light weight and small damping, and are easy to generate various wind-induced vibrations under the excitation of an external environment.
The problem of sling vibration of a large-span suspension bridge has been known for a long time, the problem of sling vibration is found in a Japanese Ming Shi Hai Dai bridge, a British Seiyun bridge, a China Western optical department bridge and the like, and because the slenderness ratio of the sling is large and the initial damping ratio is small, the improvement of the damping of the sling is an effective measure for inhibiting the sling vibration, various vibration reduction measures are adopted for the bridge, and the vibration of the sling is inhibited within an allowable range.
At present, a damping device is generally adopted to realize the vibration damping effect, the bottom surface of an inner cavity of the damping device is generally a spatial arc-shaped curved surface, the arc radius determines that the damping device has natural frequency, and when a steel ball rolls in the damping device, the steel ball can be understood as simple pendulum motion.
With the great development of bridge engineering in China, particularly for bridges which are at sea mouths and have complex wind environments, higher requirements are put forward for the damping requirements of the slings of the bridges. Generally, the sling of the suspension bridge is generally arranged as a double sling or a four sling, and from the aspect of frequency, the sling can generate combined vibration of a plurality of frequencies along with different external excitations; from the aspect of the mode shape, there are also a plurality of mode shapes. Therefore, the development of the damper is yet to be further advanced.
SUMMERY OF THE UTILITY MODEL
To the defect that exists among the prior art, the utility model aims to provide a be applied to flexible collision damping device and system of suspension bridge hoist cable.
To achieve the above objects, in a first aspect, embodiments of the present invention provide a flexible impact damping device applied to a suspension cable of a suspension bridge, for suppressing vibration of the suspension cable; the damping device includes:
a box-shaped frame, the bottom of which is a plane;
the two cable clamps are respectively sleeved on the two suspension cables and are arranged on two sides of the box-shaped frame; the two cable clamps are connected through the box-type frame;
the damping unit is arranged in the box-shaped frame; the damping unit includes:
a rigid sheath;
the flexible damping ring is fixedly connected with the box-type frame through the rigid sheath; the rigid sheath is attached to the outer wall of the flexible damping ring;
a ball disposed in an inner cavity of the flexible damping ring and having an air gap with an inner wall of the flexible damping ring such that the ball rolls freely on a bottom of the flask-shaped frame to collide with the flexible damping ring.
On the basis of the technical scheme, the balls are steel balls.
On the basis of the technical scheme, when the ball is static at the center of the flexible damping ring, the size of the air gap is 1-6 mm.
On the basis of the technical scheme, three damping units are arranged in the box-shaped frame in a single row.
On the basis of the technical scheme, the flexible damping ring is a high-damping rubber ring with an external tooth shape.
On the basis of the technical scheme, the flexible damping ring is a flexible bag, and damping particles or high-molecular viscoelastic materials are filled in the flexible bag.
On the basis of the technical scheme, the inner ring of the cable clamp is also provided with a rubber pad which is used for being attached to the surface of the sling.
In a second aspect, embodiments of the present invention further provide a flexible impact damping system for suspension bridge cables, the damping system including two cables and at least one damping device connecting the two cables; each of the damping devices includes:
a box-shaped frame, the bottom of which is a plane;
the two cable clamps are respectively sleeved on the two suspension cables and are arranged on two sides of the box-shaped frame; the two cable clamps are connected through the box-type frame;
the damping unit is arranged in the box-shaped frame; the damping unit includes:
the flexible damping ring is fixedly arranged in the box-shaped frame;
a ball disposed in an inner cavity of the flexible damping ring and having an air gap with an inner wall of the flexible damping ring such that the ball rolls freely on a bottom of the flask frame to collide with the flexible damping ring; when the steel ball is still at the center of the flexible damping ring, the size of the air gap is 1-6 mm.
On the basis of the technical scheme, the damping device is assembled at the position of the multi-stage vibration mode of the sling, which has the relative maximum displacement.
On the basis of the technical scheme, the damping system comprises a plurality of damping devices, and the damping devices are distributed on the sling at intervals.
Compared with the prior art, the utility model has the advantages of:
the utility model provides a flexible collision damping device applied to suspension bridge slings, a ball is placed on the bottom of a box-type frame, when the slings vibrate in any direction, the ball rolls freely on the bottom of the box-type frame under the action of inertia force to collide a flexible damping ring, the inner part of the flexible damping ring deforms to play a damping energy dissipation role and suppress the vibration of the slings, and the damping device can control the vibration of the slings in any direction; the ball rolls and collides on a plane, and the rolling is independent of the frequency, so the damping device can control the vibration of the sling at different frequencies; secondly, the arrangement of the plurality of damping units fully utilizes the internal space of the box frame, and the stability of vibration reduction of the damping device is enhanced;
the utility model also provides a flexible collision damping system applied to the suspension bridge sling, the sling can generate the vibration of a plurality of vibration modes, and the maximum vibration amplitude of the vibration modes corresponding to each step is different, therefore, the installation position of the damping device is optimized, namely, the installation position of the damping device is positioned at the maximum vibration amplitude of the vibration modes as much as possible; and a plurality of damping devices are installed, and the plurality of damping devices complement and work cooperatively to effectively control the multi-stage vibration mode.
Drawings
FIG. 1 is a schematic vertical sectional view of a flexible impact damping device for use in a suspension bridge cable according to an embodiment of the present invention;
FIG. 2 is a schematic cross-sectional view taken along A-A of FIG. 1;
FIG. 3 is a schematic view of a flexible impact damping system applied to a suspension bridge cable in an embodiment of the invention with the cable at rest;
FIG. 4 is a schematic view of an embodiment of the present invention showing a flexible impact damping system applied to a suspension bridge cable in a first-order mode of vibration;
FIG. 5 is a schematic view of an embodiment of the present invention showing a flexible impact damping system applied to a suspension bridge cable in a second order mode of vibration;
FIG. 6 is a schematic view of an embodiment of the present invention showing a flexible impact damping system applied to a suspension bridge cable in a state of third order mode vibration;
FIG. 7 is a schematic view of a flexible impact damping system applied to a suspension bridge cable in an embodiment of the present invention with the cable in a four-order mode of oscillation;
FIG. 8 is a schematic view of a flexible crash damping system for a suspension bridge cable in an embodiment of the invention with the cable in a five-order mode of oscillation;
FIG. 9 is a schematic view of a flexible crash damping system for a suspension bridge cable in an embodiment of the invention with the cable in a six-order mode of oscillation;
FIG. 10 is a schematic view of a flexible crash damping system for a suspension bridge cable in an embodiment of the invention with the cable in a seven order mode of oscillation;
FIG. 11 is a schematic view of an embodiment of the present invention showing a flexible crash damping system applied to a suspension bridge cable in an eight-order mode of vibration;
in the figure: 1-box type frame, 2-cable clamp, 3-sling, 4-damping unit, 41-flexible damping ring, 42-steel ball, 43-rigid sheath, 44-smooth flat plate, 45-air gap, 5-rubber pad, 6-damping device.
Detailed Description
The technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings, and it is to be understood that the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. It is to be noted that all the figures are exemplary representations. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The present invention will be described in further detail below with reference to specific embodiments and with reference to the accompanying drawings.
Examples
Referring to fig. 1-2, an embodiment of the present invention provides a flexible impact damping device applied to a suspension cable of a suspension bridge, which is used for suppressing vibration of a suspension cable 3; the damping device comprises a box-shaped frame 1, two cable clamps 2 and at least one damping unit 4; the bottom of the box-shaped frame 1 is a plane; the two cable clamps 2 are respectively sleeved on the two slings 3 and are arranged on two sides of the box-shaped frame 1; the two cable clamps 2 are rigidly connected through the box-shaped frame 1 and used for restraining relative movement between the suspension cables 3; the damping unit 4 is arranged in the box-shaped frame 1; the damping unit 4 comprises a rigid sheath 43, a flexible damping ring 41 and a ball 42, wherein in the embodiment, the ball 42 is a steel ball; the flexible damping ring 41 is fixedly connected with the box frame 1 through the rigid sheath 43, and the rigid sheath 43 is attached to the outer wall of the flexible damping ring 41; the ball 42 is placed in the inner cavity of the flexible damping ring 41 and an air gap 45 exists with the inner wall of the flexible damping ring 41, so that the ball 42 is in free rolling collision on the bottom of the box frame 1.
The embodiment of the utility model provides a be applied to flexible collision damping device of suspension bridge hoist cable, the steel ball is on box frame bottom, and in the region that flexible damping ring was injectd, when arbitrary direction's vibration takes place for the hoist cable, the steel ball takes place free roll and bump flexible damping ring under the effect of inertial force on box frame bottom, and deformation takes place for the flexible damping ring inside, consequently is in attached one deck rigid sheath 43 on the outer wall of flexible damping ring, it accepts the deformation flexible damping ring 41 to exert damping power consumption effect better, restrain the vibration of hoist cable. The damping device can control the vibration of the sling in any direction; and the steel balls roll and collide on a plane, and the rolling of the steel balls is irrelevant to the frequency, so that the damping device can control the vibration of the sling at different frequencies.
When the ball 42 is still at the center of the flexible damping ring 41, the size of the air gap 45 is 1-6 mm. The size of the air gap is related to the vibration frequency and the vibration amplitude of the cable (generally, the low-frequency vibration amplitude of the sling is large, and the high-frequency vibration amplitude of the sling is small), and the air gap 45 is the minimum distance between the ball 42 and the inner wall of the flexible damping ring 41. When the air gap is too large, the time interval from rest to collision of the steel balls in the flexible damping ring 41 is relatively large, so that the sling already generates relatively obvious vibration before collision, the vibration damping effect of the sling is not obvious, and when the air gap is too small, the impact force of the steel balls in the flexible damping ring 41 is limited, so that the damping energy consumption effect can be reduced, therefore, the size of the air gap 45 is preferably in the range of 1-6 mm in an actual test, the steel balls freely roll on the bottom of the box-type frame under the action of inertia force and collide with the flexible damping ring, the inner part of the flexible damping ring deforms, the damping energy consumption effect is played, the vibration of the sling is suppressed, and the damping device can control the vibration of the sling in any direction.
In the embodiment of the present invention, the flexible damping ring 41 is a high damping rubber ring with external tooth shape; or the flexible damping ring 41 is a flexible bag, and damping particles or a high molecular viscoelastic material are filled in the flexible bag. In practical tests, the damping energy consumption efficiency of the flexible damping ring 41 which is a flexible bag is higher than that of a high-damping rubber material, so that the material selection of the flexible damping ring 41 can be selected preferentially.
Further, the damping unit 4 further comprises a smooth flat plate 44 laid on the bottom of the box frame 1. The smooth flat plate 44, which in this embodiment is approximately 1.5mm thick, has a smoother surface layer, and the greater sensitivity to free rolling of the steel balls on the bottom of the box frame under the force of inertia and impact against the flexible dampening ring when the sling is subjected to vibration in any direction.
Further, three damping units 4 are arranged in the box-shaped frame 1 in a single row. The arrangement of the plurality of damping units fully utilizes the internal space of the box frame, and the stability of vibration reduction of the damping device is enhanced.
Furthermore, the inner ring of the cable clamp 2 is also provided with a rubber pad 5 attached to the surface of the sling 3. The rubber pad 5 avoids the direct contact between the rigid cable clamp 2 and the sling 3, and prolongs the service life of the cable clamp 2 and the sling 3.
In a second aspect, an embodiment of the present invention further provides a flexible impact damping system applied to a suspension cable of a suspension bridge, as shown in fig. 1 to 11, the damping system includes two suspension cables 3 and at least one damping device 6 connecting the two suspension cables 3; the damping devices 6 are the damping devices, and each damping device comprises a box-shaped frame 1, two cable clamps 2 and at least one damping unit 4; the bottom of the box-shaped frame 1 is a plane; the two cable clamps 2 are respectively sleeved on the two slings 3 and are arranged on two sides of the box-shaped frame 1; the two cable clamps 2 are rigidly connected through the box-shaped frame 1 and used for restraining relative movement between the suspension cables 3; the at least one damping unit 4 is arranged in the box-shaped frame 1.
As shown in fig. 1-2, the damping unit 4 comprises a flexible damping ring 41 and a ball 42; the flexible damping ring 41 is fixedly arranged in the box-shaped frame 1; the ball 42 is placed in the inner cavity of the flexible damping ring 41 and an air gap 45 exists with the inner wall of the flexible damping ring 41, so that the ball 42 is in free rolling collision on the bottom of the box frame 1. Specifically, three damping units 4 are arranged in a single row in the box-shaped frame 1.
Further, referring to fig. 3 to 11, when the sling is in a static state or in a state of different vibration modes, the damping device 6 is located at the same position on the sling 3, and it is obtained through multiple verification, the damping device 6 is installed at a position corresponding to a larger vibration displacement in the vibration modes, and can better exert a vibration damping effect, therefore, in the embodiment of the present invention, preferably, the damping device 6 is assembled at a relative maximum displacement position of multiple vibration modes of the sling 3, that is, a position where a single or multiple damping devices 6 are located can be located at a maximum displacement position of multiple vibration modes as much as possible.
Further, the damping system comprises a plurality of damping devices 6, and the plurality of damping devices 6 are distributed on the sling 3 at intervals. And a plurality of damping devices are installed, and the plurality of damping devices complement and work cooperatively to effectively control the multi-stage vibration mode.
In the embodiment of the present invention, for the suspension cables 3 with a length within 80m, one damping device is installed between adjacent suspension cables 3, which can achieve a good damping effect; for the slings 3 with the length exceeding 80m, at least two damping devices 6 are arranged between the adjacent slings 3, and the damping effect is obvious.
The embodiment of the utility model provides a still provide a flexible collision damping system for suspension bridge hoist cable, the hoist cable can take place the vibration of a plurality of types of shaking, and the position of the maximum displacement of the type of shaking that each order corresponds is different, consequently, installs a plurality of damping device to optimize damping device's mounted position, install damping device in the maximum displacement department of the type of shaking promptly as far as possible, a plurality of damping device complement each other, collaborative work, to multistage type effective control that shakes.
The present invention is not limited to the above embodiments, and for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations are also considered to be within the protection scope of the present invention. Those not described in detail in this specification are within the skill of the art.