A method and device for controlling vibration of prestressed cables in a self-supporting iron tower

Abstract

The present invention discloses a vibration control method and device for prestressed cables in a self-supporting iron tower. The method includes arranging cross cables on the side of the tower body and / or the diagonal plane inside the tower body of the iron tower; the arrangement of the cross cables is as follows: the starting end of the cross cables is connected to the top of the tower body, and the cross cables located at the tower body are cross-transitioned using a plurality of first steering pulleys, so that the cross cables form a plurality of cross-sections on the side of the tower body or the diagonal plane inside the tower body, and the cross cables connected to the tower legs of the iron tower are each connected and fixed to a vibration reduction control device through a second steering pulley. The cross cables are integrated from top to bottom through the steering pulley, so as to realize the rapid transmission of the deformation of the tower top and each section of the tower body, play the role of shared structural deformation, and make the structure more cooperative in bearing external loads.

Description

Technical Field

[0001] The invention relates to a wind vibration control technology for a high-rise steel structure, and in particular to a vibration control method and device for a prestressed cable in a self-supporting iron tower. Background Art

[0002] High-rise steel structures are widely used in the power, communications and other industries. Various types of transmission towers are the main load-bearing structures for power energy transmission in my country, and they play an important role in ensuring power supply. As the main structure that bears the ground wire of the transmission line and its own weight, the transmission line tower mainly adopts concrete poles, guyed towers, self-supporting angle steel towers, steel pipe towers and other structural types. Among them, the self-supporting angle steel tower has significant advantages such as easy installation and transportation, and is most widely used in the transmission line tower structure. Transmission towers stand in the wild for a long time, and the operating environment is harsh. Wind loads are often the controlling loads of such high-rise tower structures.

[0003] Due to the uniqueness and complexity of the transmission tower structure and construction, it is difficult to learn from the reinforcement methods of general steel structures. Therefore, the reinforcement of transmission towers, especially angle steel towers, after disasters has always been a difficult point in engineering, and many scholars have conducted relevant research. In view of the characteristics of transmission towers, researchers from domestic institutions such as the China Electric Power Research Institute and Tongji University have drawn on the mature reinforcement technology of building steel structures and proposed several technologies for strengthening and transforming transmission towers, mainly including increasing the cross-section technology, adding auxiliary components technology, and component replacement technology.

[0004] The cross-section enlargement technology is adopted, that is, a new angle steel of the same specification is connected in parallel to the side of the original angle steel tower component through a connecting plate and bolts to form a new composite cross-section component, and its cross-section forms mainly include cross-shaped, Z-shaped, T-shaped and C-shaped. Although relevant domestic units have studied the bearing capacity of reinforced components with different cross-section forms using this method, due to the influence of the connection method and installation, the failure mode, force performance, calculation method and reinforcement effect of the reinforced components are difficult to calculate accurately, and the on-site installation is relatively difficult, which seriously affects the promotion and application of transmission tower reinforcement and transformation technology.

[0005] Component replacement technology, as the name implies, is a technology that allows certain components of the tower to be replaced on site with higher specifications or higher strength components when the force is not satisfied. In general, the main materials of the angle steel tower are connected by node plates and anchored by bolts, similar to rigid connection, while the diagonal materials and auxiliary materials are connected to other components by bolts, similar to hinged connection. Although most angle steel tower components are connected by ordinary bolts and are easy to disassemble and install, in specific projects, when replacing components on existing tower structures, during the replacement of the main materials, diagonal materials or auxiliary materials of the tower, there will be certain risks to the force and safety of the tower structure, especially for the main materials and diagonal materials with significant reinforcement effects. In addition, the replacement of components of different specifications will inevitably bring local changes to the connection plates or structural measures of the existing structure, which will also make replacement and application difficult. Therefore, before replacing components, it is necessary to track and simulate the mechanical properties of the structure during the component replacement process, analyze and evaluate the safety of the structure during the recovery process, and if there is danger, temporary measures must be added to ensure the safety and reliability of the recovery process.

[0006] From the existing literature, the current reinforcement technology for existing angle steel transmission towers is mainly carried out from the aspect of component or node strength reinforcement. There are two problems: First, there are many types of loads on the transmission tower. In addition to considering wind, gravity and other effects, the transmission tower must also consider the load effects of conductor and ground wire breakage, ice coating, maintenance, etc., and there are many combined load conditions. Therefore, the method of strengthening the local structure and components can only improve the local bearing capacity of the structure and the force performance under certain load conditions, but cannot comprehensively improve the stiffness and bearing capacity of the structure, especially for dynamic loads such as strong winds and earthquakes. Second, it is difficult to implement the method of replacing components and increasing cross-sections. There are many components in the iron tower. For example, the main material is connected to other components on the front and side. Therefore, it is difficult to add new components to the original structure, and the connection between the new components and the original components is not easy to achieve. In particular, the node structure of the iron tower is relatively complex, such as the connection between the cross arm and the tower body and the tower body slope change, etc. There are many connected components, and the spatial directions are different, so the strengthening effect is difficult to guarantee.

[0007] In order to solve the above problems, in addition to the traditional reinforcement method of increasing the cross-section to improve the wind resistance of the transmission tower itself, there is another way to use vibration control technology, such as using damping energy dissipation technology to dissipate the energy input by wind load or using tuned mass dampers (TMD) to control the wind vibration response of the transmission tower. Most of these methods remain in theoretical research and experimental research. In actual projects, it is difficult to promote and apply them due to cost, implementation difficulties or the impact on the operation of the transmission tower after implementation. Prestressed cables, as a component with excellent tensile properties, are widely used in large-span and high-rise structural systems and steel structure reinforcement projects and play an important role. In transmission line projects, a large number of cables are also used in cable towers and temporary construction facilities. By arranging a number of cables outside the structure, the overturning stability of the main structure under various loads is ensured. However, there are fewer technologies and patents for arranging cables inside the self-supporting transmission tower to reinforce and control the wind vibration response of the iron tower.

[0008] Transmission towers are tall structures that are very sensitive to wind. Wind loads are often the controlling loads of such structures. Under strong winds, the collapse and local damage of transmission towers are mainly caused by the dynamic effects of wind speeds exceeding the design wind speed and pulsating wind vibration. Strengthening transmission towers and suppressing their wind vibration mechanical response are the main technical means to improve the wind resistance of transmission towers. At present, both wind-resistant reinforcement technology and wind vibration control technology for transmission towers have their technical limitations. Traditional reinforcement technology mainly increases the strength level and lateral stiffness of components by increasing the cross-section of rods, while existing wind vibration control technologies mostly set TMD dampers on the top of the tower to tune and reduce vibration of the tower. The rod section enlargement reinforcement technology is often a local enlargement, which is difficult to construct on site and is prone to problems such as low local strength and inability to strengthen node strength. The TMD tuned mass vibration reduction technology requires the addition of a larger mass on the top of the tower, which will increase the load on the tower and make on-site maintenance and operation very inconvenient. In addition, the existing reinforcement and wind vibration control technologies are often independent of each other. The reinforcement technology can improve the static load wind resistance of the transmission tower to a certain extent, but it has no vibration reduction effect. Under the cumulative effect of pulsating wind dynamic loads, the locally strengthened tower is also likely to collapse due to wind vibration. The existing TMD wind vibration control technology, by adding a larger tuned mass block on the top of the tower, not only makes it very difficult to install and arrange the TMD on the top of the tower, but also brings a load effect to the tower under the action of static wind. Summary of the invention

[0009] In order to solve the problem of poor wind and earthquake safety of existing iron towers, the present invention provides a vibration control method and device for prestressed cables in a self-supporting iron tower body. The present invention makes full use of the structural characteristics of the transmission tower frame, does not weaken the strength of the nodes and rods of the original iron tower structure, can increase the local inter-node stiffness, and can also increase the stiffness of the iron tower as a whole, improve the lateral displacement and torsion resistance of the transmission tower under wind load, and in addition, the relative displacement of the upper and lower parts of the iron tower is driven by the deformation of a group of cross cables to drive the vibration reduction control device installed on the ground foundation to produce damping energy dissipation effect, quickly attenuate the energy input by dynamic loads such as wind and earthquake, and ensure the wind and earthquake safety of the iron tower.

[0010] To achieve the above object, the technical solution of the present invention is:

[0011] In a first aspect, the present invention provides a method for controlling vibration of prestressed cables in a self-supporting iron tower, wherein cross cables are arranged on the side of the tower body and / or on the diagonal plane inside the tower body;

[0012] The arrangement of the cross cables is as follows:

[0013] Connecting the starting ends of the cross cables to the top of the tower body, and using a plurality of first deflection pulleys to cross-transition the cross cables located at the tower body, so that the cross cables form a plurality of cross-sections on the side of the tower body or the diagonal plane inside the tower body, and each of the cross cables connected to the tower legs of the tower body is connected and fixed to the vibration reduction control device through a second deflection pulley;

[0014] Wherein, the cross cable includes two cables.

[0015] Furthermore, when the cross cables are arranged on the side of the tower body of the iron tower:

[0016] The first steering pulleys are installed at intervals in the height direction of two tower body main materials opposite to each other on the side of the tower body, and the second steering pulleys are installed at the tower legs or the bases of the two tower body main materials opposite to each other on the side of the tower body;

[0017] The starting end of one of the cross cables is connected to the top of a main material of the tower body on the side of the tower body, and the starting end of the other cable is connected to the top of another main material of the tower body on the side of the tower body, and then the two cables of the cross cable are crossed and passed around the first steering pulley from top to bottom in sequence to form a plurality of cross-sections on the side of the tower body; after the two cables of the cross cable are crossed and passed around the first steering pulley in sequence from top to bottom, they are connected to the second steering pulley so that the angles of the two cables of the cross cable are adjusted to be relative to the ground, and the end of one of the cables of the cross cable is connected to one side of the vibration reduction control device, and the other side of the vibration reduction control device is connected to the end of the other cable of the cross cable.

[0018] Furthermore, the cross cables are arranged on four sides of the tower body of the iron tower.

[0019] Furthermore, when cross cables are arranged on the side of the tower body of the iron tower, planar cable clamps are provided at the intersection points of the cross cables.

[0020] Furthermore, when the cross cables are arranged on a diagonal plane inside the tower body of the iron tower:

[0021] The first steering pulleys are installed at intervals in the height direction of the two tower body main materials on the diagonal plane inside the tower body, and the second steering pulleys are installed at the tower legs or the base of the two tower body main materials on the diagonal plane inside the tower body;

[0022] The starting end of one of the cross cables is connected to the top of a main material of the tower body on the diagonal plane inside the tower body, and the starting end of the other cable is connected to the top of another main material of the tower body on the diagonal plane inside the tower body. Then, the two cables of the cross cable cross and pass around the first steering pulley in sequence from top to bottom to form a plurality of cross-sections on the diagonal plane inside the tower body; after the two cables of the cross cable cross and pass around the first steering pulley in sequence from top to bottom, they are connected to the second steering pulley so that the angles of the two cables of the cross cable are adjusted to be relative to the ground, and the end of one of the cables of the cross cable is connected to one side of the vibration reduction control device, and the other side of the vibration reduction control device is connected to the end of the other cable of the cross cable.

[0023] Furthermore, the cross cables are arranged on two diagonal planes of the tower body of the iron tower.

[0024] Furthermore, when the cross cables are arranged on both diagonal planes of the tower body of the iron tower, if the four cables of the two groups of cross cables cross at one point, a spatial cable clamp is provided at the intersection; if the four cables of the two groups of cross cables do not cross at one point, a plane cable clamp is arranged at the intersection position of each group of cross cables.

[0025] Furthermore, the starting ends of the two cables of the cross cable are provided with cable end anchors, and the cable end anchors are connected to the cable end clamps at the top of the main material of the tower body.

[0026] Furthermore, the cable end clamp and the first steering pulley are connected to the main material of the tower body by using a clamp.

[0027] Furthermore, when two cables of the cross cable encounter obstacles at the turning point of the main material of the tower body, two of the first turning pulleys are arranged above and below the obstacle point to jump over the obstacle point of the main material of the tower body.

[0028] Furthermore, the vibration reduction control device is a viscous damper.

[0029] Furthermore, when the cross cables are arranged on the four side surfaces of the tower body and the two diagonal planes of the tower body, tower body cable steering mechanisms are installed at intervals in the height direction of the four main materials of the tower body, and the tower body cable steering mechanism includes an inner plywood and an outer plywood matching the cross-section of the tower body main material, and the inner plywood and the outer plywood are correspondingly assembled on the inner and outer side surfaces of the tower body main material and connected and fixed by connecting parts; tower body side cable pulley fixing plate frames are arranged on both side surfaces of the outer plywood, and the first steering pulley for arranging the tower body side cables is installed in the tower body side cable pulley fixing plate frames; a tower body internal diagonal plane cable pulley fixing plate frame is arranged in the inner plywood, and the first steering pulley for arranging the tower body internal diagonal plane cables is installed in the tower body internal diagonal plane cable pulley fixing plate frame.

[0030] In a second aspect, the present invention provides a vibration control device for prestressed cables in a self-supporting iron tower, comprising:

[0031] A first diverting pulley, the first diverting pulley is used to be installed at intervals in the height direction of two tower body main materials opposite to each other on the tower body side of the iron tower;

[0032] A second diverting pulley, the second diverting pulley is used to be installed at the tower legs or the base of two tower body main materials opposite to each other on the tower body side of the iron tower;

[0033] A cross-stay cable, wherein the cross-stay cable comprises two stay cables, wherein the starting end of one of the stay cables is connected to the top of a main material of the tower body on the side of the tower body, and the starting end of the other stay cable is connected to the top of another main material of the tower body on the side of the tower body, and then the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom to form a plurality of cross-sections on the side of the tower body; after the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom, they are connected to the second steering pulley, so that the angles of the two stay cables of the cross-stay cable are adjusted to be relative to the ground;

[0034] A vibration reduction control device, one side of which is connected to the end of one of the cross cables, and the other side of which is connected to the end of the other cross cable.

[0035] In a third aspect, the present invention provides a vibration control device for prestressed cables in a self-supporting iron tower, comprising:

[0036] A first diverting pulley, the first diverting pulley is used to be installed at intervals in the height direction of two tower body main materials opposite to each other in the diagonal plane inside the tower body of the iron tower;

[0037] A second diverting pulley, the second diverting pulley is used to be installed at the tower legs or the base of two tower body main materials opposite to each other in the diagonal plane inside the tower body of the iron tower;

[0038] A cross-stay cable, wherein the cross-stay cable comprises two stay cables, wherein the starting end of one stay cable of the cross-stay cable is connected to the top of a main material of the tower body on the diagonal plane inside the tower body, and the starting end of the other stay cable is connected to the top of another main material of the tower body on the diagonal plane inside the tower body, and then the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom to form a plurality of cross-section segments on the diagonal plane inside the tower body; after the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom, they are connected to the second steering pulley, so that the angles of the two stay cables of the cross-stay cable are adjusted to be relative to the ground;

[0039] A vibration reduction control device, one side of which is connected to the end of one of the cross cables, and the other side of which is connected to the end of the other cross cable.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The cable is integrated from top to bottom through the steering pulley, which can realize the rapid transmission of the deformation of the tower top and each tower body segment, play the role of shared structural deformation, and make the structure more coordinated in bearing external loads.

[0042] 2. By setting a steering pulley at the node of the main material of the tower body in the inter-segment section, the angle between the cable and the main material of the tower body can more easily meet the inclination requirements of the cable, avoiding the phenomenon of the cable failing due to excessive inclination.

[0043] 3. The two cables in the cross cable group are connected together through a vibration reduction control device arranged on the ground. The relative displacement at the tower top or each node of the tower body drives the vibration reduction control device located on the ground through two prestressed cables, which plays a role in vibration control and damping energy consumption to ensure the wind and earthquake resistance of the iron tower. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1-4 A schematic diagram of the arrangement of a cable-pulley-vibration reduction control device on the side of a transmission tower provided by an embodiment of the present invention;

[0045] Figure 5-8 A schematic diagram of the arrangement of a diagonal plane cable-pulley-vibration reduction control device inside a transmission tower body provided by an embodiment of the present invention;

[0046] Fig. 9 It is a structural schematic diagram of the tower cable steering mechanism;

[0047] Fig.10 for Fig. 9 A top view of

[0048] Fig.11 It is the three-dimensional geometric diagram of the tower body internode segment AB;

[0049] In the figure: 1. tower body; 2. main material of tower body; 4. tower foundation; 5-1. cable; 5-2. first steering pulley; 5-3. second steering pulley; 5-4. cable end anchor; 5-5. cable end main material clamp; 5-6. tower body main material clamp; 5-7. vibration reduction control device; 5-8. foundation of vibration reduction control device; 5-9. cable clamp; 6. tower body cable steering mechanism; 6-1. inner splint; 6-2. outer splint; 6-3. bolt; 6-4. cable pulley fixing plate frame on the side of tower body; 6-5. cable pulley fixing plate frame on the diagonal plane inside the tower body. DETAILED DESCRIPTION

[0050] Example:

[0051] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0052] Regarding the reasons for the collapse and damage of transmission line towers under typhoons and strong typhoons, it is generally believed that it is because the wind speed of the typhoon far exceeds the design value. The design principle of wind-resistant reinforcement is to increase the design wind speed. Increasing the design wind speed can certainly improve the wind resistance of the tower, but it will also significantly increase the construction cost of the transmission line. In fact, the collapse and damage of transmission towers under typhoons are not only due to the small design wind speed, but also due to the micro-topography and micro-meteorology of the tower location, wind load characteristics (turbulence characteristics, gust effects, etc.), transmission line tower-line system (tower-line coupling effect, unequal height difference and unbalanced front and rear spacing), damage to tower rods, loose bolts, tower design and other possible factors.

[0053] The self-supporting iron tower of a transmission line (referred to as the transmission tower) generally consists of an iron tower foundation 4, a tower body 1 and a tower head. It mainly bears the gravity load of the transmission line ground wire, the weight of the iron tower, the construction wiring, the tension load of the ground wire, and the external loads of the iron tower and the ground wire system such as wind, ice, snow, and earthquake. Among them, the combined load under strong wind conditions often becomes the control load of the transmission tower and plays a controlling role in the bearing capacity of the transmission tower. Under the action of average wind, the transmission tower is subjected to large lateral deformation and bending moment. At the same time, the transmission tower is a high-flexible structure. The wind vibration effect under the action of pulsating wind is very large, and it is very easy to be damaged by dynamic overload. Therefore, taking measures to strengthen the tower body and control wind vibration, improving the lateral stiffness of the tower body, reducing the overall lateral deformation of the transmission tower and quickly consuming the energy input by wind vibration is an important technical route to improve the wind resistance of the transmission tower.

[0054] Transmission towers are tall structures that are very sensitive to wind. Wind loads are often the controlling loads of such structures. Under strong winds, the collapse and local damage of transmission towers are mainly caused by the dynamic effects of wind speeds exceeding the design wind speed and pulsating wind vibration. Strengthening transmission towers and suppressing their wind vibration mechanical response are the main technical means to improve the wind resistance of transmission towers. At present, both wind-resistant reinforcement technology and wind vibration control technology for transmission towers have their technical limitations. Traditional reinforcement technology mainly increases the strength level and lateral stiffness of components by increasing the cross-section of rods, while existing wind vibration control technologies mostly set TMD dampers on the top of the tower to tune and reduce vibration of the tower. The rod section enlargement reinforcement technology is often a local enlargement, which is difficult to construct on site and is prone to problems such as low local strength and inability to strengthen node strength. The TMD tuned mass vibration reduction technology requires the addition of a larger mass on the top of the tower, which will increase the load on the tower and make on-site maintenance and operation very inconvenient. In addition, the existing reinforcement and wind vibration control technologies are often independent of each other. The reinforcement technology can improve the static load wind resistance of the transmission tower to a certain extent, but it has no vibration reduction effect. Under the cumulative effect of pulsating wind dynamic loads, the locally strengthened tower is also likely to collapse due to wind vibration. The existing TMD wind vibration control technology, by adding a larger tuned mass block on the top of the tower, not only makes it very difficult to install and arrange the TMD on the top of the tower, but also brings a load effect to the tower under the action of static wind.

[0055] To this end, the present invention divides the tower body 1 from the base platform into a plurality of intersegments according to the tower body structure layout and the cable setting angle requirements. The upper and lower ends of each intersegment are numbered in sequence from top to bottom using capital letters A, B, C, etc. The main material nodes of the plane section of the upper and lower ends of the intersegment are numbered in sequence counterclockwise from the left tower leg on the small side of the line direction, such as Figure 2 The four nodes of the tower leg section in / 4 / 6 / 8 are arranged counterclockwise as E1, E2, E3, and E4.

[0056] The key to the vibration control method of prestressed cables in a self-supporting iron tower body proposed by the present invention is to arrange 1-4 groups of full-length prestressed cross cables in pairs in the tower body according to the structural characteristics of the iron tower and the needs of reinforcement and wind vibration control. Each cable is at the node of the tower body main material 2 in the internode section. A pre-designed tower body main material clamp and a first steering fixed pulley 5-2 are used to move the two cables in the group from top to bottom until they reach the tower leg, and then through the second steering fixed pulley 5-3 preset at the iron tower foundation 4 or the end of the tower leg main material, the two cables are symmetrically connected to the two sides of the vibration reduction control device 5-7. Through this technical innovation and arrangement, the following effects can be achieved: First, the prestressed cable is integrated from top to bottom through the steering pulley, which can realize the rapid transmission of the deformation of the tower top and each inter-section tower body, play the role of shared structural deformation, and make the structure more coordinated in bearing external loads; secondly, by arranging a steering pulley at the node of the main material of the tower body in the inter-section, the angle between the cable and the main material of the tower body can more easily meet the inclination requirement of the cable, avoiding the phenomenon of failure of the cable due to excessive inclination; finally, the two cables in the group are connected together through the vibration reduction control device 5-7 arranged on the ground, and the displacement of the top of the tower body or each node of the tower body drives the vibration reduction control device through the two prestressed cables, which plays the role of vibration control and damping energy consumption.

[0057] There are two types of cable vibration control methods for self-supporting iron towers according to the arrangement of the cables. The first type is a plane arrangement inside the tower, that is, a side arrangement of the tower body. The side of the tower body refers to the plane between two adjacent tower body main materials 2 of the tower body. Figure 1-4 This is a schematic diagram of the layout of the cable-pulley-vibration control device on the side of a typical transmission tower. The other is the spatial layout inside the tower, that is, the diagonal plane layout inside the tower. The diagonal plane inside the tower refers to the plane between the two tower main materials 2 diagonally opposite to each other. Figures 5 to 8 It is a schematic diagram of the layout of the diagonal plane cable-pulley-vibration reduction control device inside the tower body of a typical transmission tower; the prestress of the cable is generally 100-200MPa.

[0058] The method for controlling the vibration of the cables on the side of the transmission tower is to arrange a group of cross cables on at least one side of the tower, and the two cables of the cross cables are finally connected in series through a vibration reduction control device 5-7 arranged on the ground.

[0059] In order to further ensure the wind and earthquake resistance of the iron tower, in a preferred embodiment, Figures 5 to 8As shown, a group of cross cables are arranged in each of the four sides of the tower body 1 of the iron tower, namely the front, back, left and right sides, a total of four groups of eight cables, one group of cross cables is connected to a vibration reduction control device 5-7, and the vibration reduction control device 5-7 is installed on the vibration reduction control device base 5-8, so as to be basically level with the second deflection fixed pulley 5-3; in a specific embodiment, the vibration reduction control device 5-7 adopts a damper (viscous damper), and the four sets of vibration reduction control devices are respectively Damper1, Damper2, Damper3, and Damper4, and Damper1 to Damper4 are correspondingly arranged on the four sides of the rectangle formed by the four nodes E1-E4 of the tower leg section; in addition, in order to maintain uniform vibration reduction control, Damper1 to Damper4 are correspondingly arranged at the midpoint position of the four sides of the rectangle formed by the four nodes E1-E4 of the tower leg section. In some other embodiments, the vibration reduction control device 5-7 can adopt other types of control devices, such as an inertia container with displacement amplification function for tuning vibration reduction.

[0060] The following is an example of arranging a group of cross cables on the front of the tower to illustrate the arrangement of cross cables on the tower. Figure 1 As shown, the cable S1 located on the front of the tower body starts from the node A1 at the top of the tower body, and the cable S1 is connected to the top of the tower body main material 2, and then passes through the first steering pulley at the nodes B2, C1, D2, etc., namely the first steering pulley 5-2, and then connected to the second steering pulley at the tower leg node E1, namely the second steering pulley 5-3. The angle of the cable S1 is adjusted to be relative to the ground and then connected to the control device Damper1 set on the ground. The other side of Damper1 is connected to another cross cable S2 in the same group; in this way, when there is deformation and displacement at any position in the side of the tower body, the two cross cables can be driven to move relative to each other, and the relative movement of the cable causes the Damper to deform relative to each other, thereby playing the role of vibration reduction and energy consumption or tuning vibration absorption. Preferably, the starting end of the cable S1 is installed with a cable end anchor 5-4, and the end anchor 5-4 is connected to the cable end clamp 5-5 on the top of the tower body main material 2, so as to realize the connection between the starting end of the cable S1 and the top of the tower body main material 2.

[0061] The arrangement of a group of cross cables on the back and left and right sides of the tower body is the same as the arrangement of the cross cables on the front of the tower body, and will not be repeated in this embodiment.

[0062] The principle of the method for controlling the vibration of the diagonal plane cables inside the transmission tower is consistent with the side arrangement scheme of the tower body, except that the arrangement of the cables is different. In this embodiment, in order to ensure the effect, a group of cross cables are arranged on the two diagonal planes inside the tower body, totaling two groups of four cross cables (see Figures 5 to 8As shown in the figure, the cables are arranged in the space of the tower body to increase the internode segments and the overall stiffness of the tower body, and the overall coordination and adaptability of the tower body in spatial deformation control under external loads are improved. The steering pulley is arranged on the inner side of the angle steel, the main material of the tower body, which is more convenient to arrange. The number of additional cables, steering pulleys and ground vibration reduction control devices is reduced by 50% compared with the arrangement on the side of the tower body. Figure 5 In the scheme, the arrangement of the cross-cables in one of the diagonal planes of the tower body is used for explanation, wherein the cable S1 starts from the node A1 at the top of the tower body main material 2, the anchor 5-4 at the beginning of the cable S1 is connected to the cable end clamp 5-5 on the top of the tower body main material 2, and then passes through the first steering pulley 5-2 at the nodes B3, C1, D3, etc., and then connects to the second steering pulley 5-3 at the tower leg node E3. The angle of the cable S1 is adjusted to be opposite to the ground and then connected to the Damper1 set on the ground. The other side of Damper1 is connected to another cross cable S2 in the same group; the Damper1 is set in a diagonal of the rectangle formed by the four nodes E1-E4 of the tower leg section; the arrangement of the cross cables in the other diagonal plane of the tower body is the same as the above, so when there is deformation and displacement at any position in the diagonal plane inside the tower body, the two cross cables can be driven to move relative to each other. The relative movement of the cables causes the Damper to deform relative to each other, thereby playing the role of vibration reduction and energy consumption or tuning and vibration absorption.

[0063] In a preferred embodiment, the cable end clamp 5-5 and the first deflection pulley 5-2 are connected to the tower body main material 2 by a clamp to avoid drilling holes in the tower body main material 2 and damaging the cross section of the tower body main material 2. If there is an obstacle at the designed turning point, two first deflection pulleys 5-2 can be set above and below the obstacle point to skip the obstacle point of the tower body main material 2.

[0064] In order to prevent free movement and damage of the cables due to friction at the intersection of each group of cross cables, for the side layout of the tower body, a pair of plane cable clamps 5-9 need to be set at the intersection of the cross cables to ensure that the two cables do not produce mutual friction and resistance during relative movement; for the space layout of the tower body, a pair of space cable clamps 5-9 need to be set to avoid friction and resistance between the four cables, or when arranging the space cables, according to the structural characteristics of the tower, the inter-node nodes are staggered to avoid the situation where two groups of four cables cross at one point. At this time, a plane cable clamp 5-9 can be arranged at the intersection of each group of cross cables.

[0065] In a preferred embodiment, in order to further improve the lateral displacement and torsion resistance of the transmission tower under wind load and ensure the wind and earthquake resistance of the iron tower, a group of cross cables are arranged on the four sides and two diagonal planes of the tower body 1. Since the main material of the tower body is angle steel, the cross section is L-shaped, in order to facilitate the installation of the first diverting pulley on the main material of the tower body, such as Figure 9-10 As shown, in this embodiment, a tower body cable steering mechanism 6 is also provided, which mainly includes an inner plywood 6-1 and an outer plywood 6-2 that match the cross-section of the tower body main material. The inner plywood 6-1 and the outer plywood 6-2 are correspondingly assembled on the inner and outer sides of the tower body main material 2 and are connected and fixed by bolts 6-3, so as to avoid opening holes on the tower body main material 2; tower body side cable pulley fixing plate frames 6-4 are arranged on both sides of the outer plywood 6-2, and the first steering pulley 5-2 for tower body side cable arrangement is installed in the tower body side cable pulley fixing plate frame 6-4; a tower body internal diagonal plane cable pulley fixing plate frame 6-5 is arranged in the inner plywood 6-1, and the first steering pulley 5-2 for internal space cable arrangement is installed in the tower body internal diagonal plane cable pulley fixing plate frame 6-5. That is to say, a tower body cable steering mechanism 6 can provide three first steering pulleys 5-2. When the tower body cable steering mechanism 6 is installed at intervals in the height direction of the four tower body main materials 2, a group of cross cables can be quickly arranged on the four sides of the tower body and the two diagonal planes, thereby improving the arrangement efficiency of the cross cables.

[0066] from Figure 1 Or remove the internode segment AB from the arrangement of 5 cables, see Fig.11 As shown, if the intersegment height H is known AB and the width of the upper and lower openings of the intersegment W a and W b According to the spatial geometric relationship, the inclination angle Φ of the cables arranged in the plane inside the tower body, the cables arranged in space θ and the line length Se of the theoretical cables can be calculated respectively.

[0067] Based on the above known conditions, the slope coefficient of the main material of the tower can be calculated:

[0068] (1)

[0069] Cable inclination angle in plan layout , Cables arranged in space And the theoretical cable length It is the key parameter of the cable design in the tower body, and the inclination angle and length of the cable The height of the internode And the slope coefficient of the main material of the transmission tower The inclination angle and theoretical line length of the plane and space cables in the body are closely related, respectively, as shown in formula (2) and formula (3):

[0070] (2)

[0071] (3)

[0072] (4)

[0073] From formulas (2) and (3), it can be seen that when the tower side cables and space cables are arranged in the same interval, the inclination angle of the space cables is Smaller than the inclination angle of the plane cable , from formula (4), we can know that the theoretical length of the space cable in the body is It is longer than the theoretical length of the tower side cables, but the range of variation is 1- From the above analysis, the use of internal space cables can reduce the number of cables compared to plane cables, and the total cable length will also be greatly reduced. The layout angle is smaller than that of plane cables, and the layout is more flexible.

[0074] Usually, the slope coefficient or inclination angle of the main material of the transmission tower is generally less than 10°. In order to maximize the effect of the cable, the height of the inter-section The width of the opening on the internode segment can be determined so that the inclination angle of the cable or At about 45°, in order to ensure that the cable can play a better role in the plane where it is set, the inclination angle of the cable or Try to set it to about 45°, and adjust it appropriately up and down according to the inter-node distribution of the tower body. It is within a reasonable range.

[0075] The slope coefficient of the main material of the tower is known and the width of the opening on the intersegment Wa , according to the cable inclination or The designed value range can determine the position of the lower opening Wb of the tower segment and calculate the height of the inter-segment segment. The reasonable design value of is:

[0076] (5)

[0077] After obtaining the reasonable design height range of the inter-segment, we can select the reasonable node segment height from top to bottom according to the structural characteristics of the tower, so as to determine the installation position of the main material fixture of the tower. The main material fixture installation position should be as close as possible to the tower body diaphragm surface or the intersection of the upper and lower diagonal materials to ensure that the tension of the cable is not only borne by the main material, but also effectively distributed to the diagonal material or horizontally to avoid the main material bearing a large bending moment due to the tension of the cable. , the inclination angle of the cable can be further determined by formulas (2), (3) and (4) or , Theoretical line length or and the width of the lower mouth of the internode segment W b Equal design value.

[0078] Whether it is the side cable of the tower or the space cable inside the tower, the theoretical length of each cable is from the starting node of the cable end to the full length of the ground vibration control device. It is equal to the sum of the theoretical lengths of the cables in each section of the tower. In addition, the increased length of the pulley and the part relative to the ground must be considered, which can be expressed as shown in formula (6).

[0079] (6)

[0080] Where: It is an additional full-length cable. is the theoretical length of a certain intersegment. The number of intersegments, is the added length of the pulley. The length of the cable after it passes through the tower leg or foundation diverting pulley and before the vibration reduction control device.

Claims

1. A method for controlling vibration of prestressed cables in a self-supporting iron tower, characterized in that: Cross cables are arranged on the side of the tower body and / or the diagonal plane inside the tower body of the iron tower; The arrangement of the cross cables is as follows: Connecting the starting ends of the cross cables to the top of the tower body, and using a plurality of first deflection pulleys to cross-transition the cross cables located at the tower body, so that the cross cables form a plurality of cross-sections on the side of the tower body or the diagonal plane inside the tower body, and each of the cross cables connected to the tower legs of the tower body is connected and fixed to the vibration reduction control device through a second deflection pulley; Wherein, the cross cable comprises two cables; When the cross cables are arranged on the side of the tower body of the iron tower: The first steering pulleys are installed at intervals in the height direction of two tower body main materials opposite to each other on the side of the tower body, and the second steering pulleys are installed at the tower legs or the bases of the two tower body main materials opposite to each other on the side of the tower body; The starting end of one of the cross cables is connected to the top of a main material of the tower body on the side of the tower body, and the starting end of the other cable is connected to the top of another main material of the tower body on the side of the tower body, and then the two cables of the cross cable are crossed and passed around the first steering pulley from top to bottom in sequence to form a plurality of cross-sections on the side of the tower body; after the two cables of the cross cable are crossed and passed around the first steering pulley in sequence from top to bottom, they are connected to the second steering pulley so that the angles of the two cables of the cross cable are adjusted to be parallel to the ground, and the end of one of the cables of the cross cable is connected to one side of the vibration reduction control device, and the other side of the vibration reduction control device is connected to the end of the other cable of the cross cable.

2. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1, characterized in that: The cross cables are arranged on four sides of the tower body of the iron tower.

3. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1 or 2, characterized in that: When cross cables are arranged on the side of the tower body of the iron tower, planar cable clamps are provided at the intersection points of the cross cables.

4. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1, characterized in that: When the cross cables are arranged on a diagonal plane inside the tower body of the iron tower: The first steering pulleys are installed at intervals in the height direction of the two tower body main materials on the diagonal plane inside the tower body, and the second steering pulleys are installed at the tower legs or the base of the two tower body main materials on the diagonal plane inside the tower body; The starting end of one of the cross cables is connected to the top of a main material of the tower body on the diagonal plane inside the tower body, and the starting end of the other cable is connected to the top of another main material of the tower body on the diagonal plane inside the tower body. Then, the two cables of the cross cable cross and pass around the first steering pulley in sequence from top to bottom to form a plurality of cross-sections on the diagonal plane inside the tower body; after the two cables of the cross cable cross and pass around the first steering pulley in sequence from top to bottom, they are connected to the second steering pulley so that the angles of the two cables of the cross cable are adjusted to be relative to the ground, and the end of one of the cables of the cross cable is connected to one side of the vibration reduction control device, and the other side of the vibration reduction control device is connected to the end of the other cable of the cross cable.

5. The method for controlling vibration of prestressed cables in a self-supporting iron tower as claimed in claim 4, characterized in that: The cross cables are arranged on two diagonal planes inside the tower body of the iron tower.

6. The method for controlling vibration of prestressed cables in a self-supporting iron tower as claimed in claim 5, characterized in that: When the cross cables are arranged on both diagonal planes inside the tower body of the iron tower, if the four cables of the two groups of cross cables cross at one point, a spatial cable clamp is provided at the intersection; if the four cables of the two groups of cross cables do not cross at one point, a plane cable clamp is arranged at the intersection position of each group of cross cables.

7. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1 or 5, characterized in that: The starting ends of the two cables of the cross cable are provided with cable end anchors, and the cable end anchors are connected to the cable end clamps on the top of the main material of the tower body.

8. The method for controlling vibration of prestressed cables in a self-supporting iron tower as claimed in claim 7, characterized in that: The cable end clamp and the first diverting pulley are connected to the main material of the tower body by using a clamp.

9. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1 or 4, characterized in that: When two cables of the cross cable encounter obstacles at the turning point of the tower body main material, two first turning pulleys are arranged above and below the obstacle point to jump over the obstacle point of the tower body main material.

10. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1, characterized in that: The vibration reduction control device is a velocity type viscous damper or a displacement type energy dissipation damper.

11. The method for controlling vibration of prestressed cables in a self-supporting iron tower according to claim 1, characterized in that: When the cross cables are arranged on the four side surfaces of the tower body and the two diagonal planes inside the tower body, tower body cable steering mechanisms are installed at intervals in the height direction of the four main materials of the tower body, and the tower body cable steering mechanism comprises an inner plywood and an outer plywood matching the cross-section of the tower body main material, and the inner plywood and the outer plywood are correspondingly assembled on the inner and outer side surfaces of the tower body main material and connected and fixed by connecting pieces; tower body side cable pulley fixing plate frames are arranged on both side surfaces of the outer plywood, and the first steering pulley for arranging the tower body side cables is installed in the tower body side cable pulley fixing plate frames; a tower body internal diagonal plane cable pulley fixing plate frame is arranged in the inner plywood, and the first steering pulley for arranging the tower body internal diagonal plane cables is installed in the tower body internal diagonal plane cable pulley fixing plate frame.

12. A vibration control device for prestressed cables in a self-supporting iron tower, characterized in that: include: A first diverting pulley, the first diverting pulley is used to be installed at intervals in the height direction of two tower body main materials opposite to each other on the tower body side of the iron tower; A second diverting pulley, the second diverting pulley is used to be installed at the tower legs or the base of two tower body main materials opposite to each other on the tower body side of the iron tower; A cross-stay cable, wherein the cross-stay cable comprises two stay cables, wherein the starting end of one of the stay cables is connected to the top of a main material of the tower body on the side of the tower body, and the starting end of the other stay cable is connected to the top of another main material of the tower body on the side of the tower body, and then the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom to form a plurality of cross-sections on the side of the tower body; after the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom, they are connected to the second steering pulley, so that the angles of the two stay cables of the cross-stay cable are adjusted to be parallel to the ground; A vibration reduction control device, one side of which is connected to the end of one of the cross cables, and the other side of which is connected to the end of the other cross cable.

13. The vibration control device for prestressed cables in a self-supporting iron tower as claimed in claim 12, characterized in that: A plane cable clamp is arranged at the intersection of the cross cables.

14. A vibration control device for prestressed cables in a self-supporting iron tower, characterized in that: include: A first diverting pulley, the first diverting pulley is used to be installed at intervals in the height direction of two tower body main materials opposite to each other in the diagonal plane inside the tower body of the iron tower; A second diverting pulley, the second diverting pulley is used to be installed at the tower legs or the base of two tower body main materials opposite to each other in the diagonal plane inside the tower body of the iron tower; A cross-stay cable, wherein the cross-stay cable comprises two stay cables, wherein the starting end of one stay cable of the cross-stay cable is connected to the top of a main material of the tower body on the diagonal plane inside the tower body, and the starting end of the other stay cable is connected to the top of another main material of the tower body on the diagonal plane inside the tower body, and then the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom to form a plurality of cross-section segments on the diagonal plane inside the tower body; after the two stay cables of the cross-stay cable sequentially cross and bypass the first steering pulley from top to bottom, they are connected to the second steering pulley, so that the angles of the two stay cables of the cross-stay cable are adjusted to be parallel to the ground; A vibration reduction control device, one side of which is connected to the end of one of the cross cables, and the other side of which is connected to the end of the other cross cable.

15. The vibration control device for prestressed cables in a self-supporting iron tower as claimed in claim 12 or 14, characterized in that: The starting ends of the two cables of the cross cable are provided with cable end anchors, and the cable end anchors are connected to the cable end clamps on the top of the main material of the tower body.

16. The vibration control device for prestressed cables in a self-supporting iron tower as claimed in claim 15, characterized in that: The cable end clamp and the first diverting pulley are connected to the main material of the tower body by using a clamp.

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