CN114635372B - A multi-tower suspension bridge reinforcement structure for overcoming mid-tower effect - Google Patents

Abstract

The invention provides a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect, which relates to the technical field of suspension bridge construction and includes a mid-tower, a side tower, a main cable, a main girder and a central buckle assembly. The central buckle assembly includes a first central buckle and a central buckle. The second central buckle, the first central buckle and the second central buckle are all I-shaped parts, the upper ends of the first central buckle and the second central buckle are connected to the mid-span position of the main cable, and there is a connection between the main cable and the main beam. A plurality of suspenders, the lower end of the first central buckle and the lower end of the second central buckle are respectively connected to the joints of the suspenders and the main beam. The invention has a simple structure and low cost. The central buckle assembly is installed in the main cable span to form a triangular truss, which can effectively increase the strength of the entire central buckle assembly, effectively improve the stiffness of the multi-tower suspension bridge, and ensure the safety of the cable bridge. It can also make two The central buckle forms mutual compensation, which effectively reduces the wear of the central buckle assembly and has a long service life.

Description

A multi-tower suspension bridge reinforcement structure for overcoming mid-tower effect

technical field

The invention relates to the technical field of suspension bridge construction,

In particular, the present invention relates to a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect.

Background technique

In recent years, with the rapid development of science and technology and the continuous improvement of people's travel quality requirements, the trend of building cross-strait and cross-river bridges at home and abroad has risen. Suspension bridges have an advantage in various schemes due to their strong spanning ability. The multi-tower suspension bridge not only solves the span problem, but also can maintain the original best rise-span ratio. However, the suspension bridge is a flexible structure, and the middle tower lacks the effective restraint of the main cable, which leads to the development of the multi-tower suspension bridge. "The hindrance. The "middle-tower effect" is a key problem that plagues the development of multi-tower suspension bridges. Because the middle tower lacks the restraint of the side-span main cable, the restraint of the main cable on the middle bridge tower is weak. Under the most unfavorable load conditions, the multi-tower suspension bridge There is a huge unbalanced force at the top of the tower. If the stiffness of the middle tower is too large, the saddle may not be able to bear the difference in cable force and cause relative sliding; if the stiffness of the middle tower is too small, the main girder will have a large deflection when it bears the load, which will affect the driving comfort.

The root cause of the "medium tower effect" is that there is no effective constraint between the main cable and the main girder, and relative displacement will occur when unbalanced loads are applied. It is necessary to establish an effective cable-beam connection. Therefore, the current technology for overcoming the mid-tower effect There are also more and more developments. For example, the Chinese patent invention CN112239992A proposes a three-tower self-anchored suspension bridge, which includes two side piers, two auxiliary piers arranged inside the two side piers, and two auxiliary piers arranged on the inside of the two auxiliary piers. There are three main towers, main beams, several main cables fixed on the main towers, and several slings for lifting the main beams. Towers, the main cable is erected between the adjacent main towers and between the auxiliary pier and the main tower. The main cable is a space cable plane, and the main cable and the main beam are connected by a central buckle at the mid-span position to constrain the relative displacement of the two. . The above-mentioned invention forms a three-tower self-anchored suspension bridge structure system through the central buckle, which increases the horizontal constraint of the mid-span main cable on the top of the mid-tower, thereby reducing the longitudinal bridgewise bending moment at the bottom of the mid-tower under unbalanced live loads. The structural size of the middle tower is reduced, the vertical rigidity of the structure is improved, and the economical span of the three-tower self-anchored suspension bridge is increased. It is applicable to the three-tower self-anchored suspension bridge with a span of more than 400m, and is suitable for long-span public rails Build bridges together.

However, the above-mentioned suspension bridge structure still has the following problems: the main cable and the main girder are only connected through the ordinary central buckle, the vertical stiffness of the structure is not enough, and when the main span is fully loaded, the central buckle can only appropriately reduce the vertical deflection effect, and cannot offset it The horizontal deflection increment not only seriously damages the central buckle structure and shortens its service life, but also affects the safety of the cable bridge.

Therefore, in order to solve the above problems, it is necessary for us to design a reasonable and efficient multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect.

Contents of the invention

The purpose of the present invention is to provide a simple structure and low installation cost. A central buckle assembly is installed in the main cable span. The two central buckles in the central buckle assembly form a triangular truss with a section of the main beam, effectively increasing the safety of the entire central buckle assembly. Strength, can effectively improve the stiffness of multi-tower suspension bridges, and has high resistance to horizontal deflection increments. Even if the main span is fully loaded, the safety of the cable bridge is still guaranteed. Compensation cables can even be installed on the triangular The two central buckles in the buckle assembly form mutual compensation, effectively reduce the wear of the central buckle assembly, have a long service life, and reduce maintenance costs. The multi-tower suspension bridge reinforcement structure is used to overcome the mid-tower effect.

In order to achieve the above object, the present invention adopts the following technical solutions to achieve:

A multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect, comprising a middle tower, a side tower, a main cable for connecting the top of the middle tower and the top of the side tower, and a main cable for connecting the bottom of the middle tower and the bottom of the side tower The main beam and the central buckle assembly for connecting the main cable and the main beam, the central buckle assembly includes a first central buckle and a second central buckle, and the first central buckle and the second central buckle are both H-shaped The upper ends of the first central buckle and the second central buckle are connected to the mid-span position of the main cable, and several suspenders are connected between the main cable and the main girder, and the mid-span position of the main cable The suspender on the side close to the middle tower is connected to the lower end of the main beam with the lower end of the first central buckle, the mid-span position of the main cable is close to the suspender on the side tower side and the The connecting part of the main beam is connected with the lower end of the second central buckle.

As a preference of the present invention, the lengths of the first central buckle and the second central buckle are the same.

As a preference of the present invention, the middle part of the first central buckle is connected to the middle part of the second central buckle through a connecting rod.

As a preference of the present invention, the lower end of the first central buckle is connected to the bottom of the second central buckle through a compensation cable.

As a preference of the present invention, the height of the compensation cable is not lower than the height of the main girder, and the mid-span position of the compensation cable is connected to the end of the connecting rod through the third central buckle, and the mid-span of the compensation cable The position is connected with the end of the connecting rod away from the third central buckle through the fourth central buckle.

As a preference of the present invention, the third central buckle and the fourth central buckle are I-shaped pieces.

As a preference of the present invention, the first central buckle, the second central buckle, the third central buckle and the fourth central buckle are all rigid parts.

As a preference of the present invention, the mid-span position of the main cable is provided with a bolt ball for connecting with the central buckle assembly, and the ends of the first central buckle and the second central buckle are both provided with bolt balls for welding with the bolt ball welding slot.

As a preference of the present invention, an anchor ring is provided at the connection between the suspender and the main beam, and the end of the first central buckle away from the welding groove and the end of the second central buckle far away from the welding groove are both provided For the welding shank welded with the anchor ring.

As a preference of the present invention, the lower side of the main beam is provided with a foundation column for connecting with the middle tower and the side towers.

The beneficial effect of a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention is that the structure is simple and the installation cost is low. A section of the triangular truss is formed to effectively increase the strength of the entire central buckle assembly, which can effectively improve the stiffness of the multi-tower suspension bridge, and has high resistance to horizontal deflection increments. Even if the main span is fully loaded, the safety of the cable bridge is still guaranteed. Even Compensation cables can be installed on the triangular truss to further enable the two central buckles in the central buckle assembly to form mutual compensation, effectively reducing the wear of the central buckle assembly, with long service life and reduced maintenance costs.

Description of drawings

Fig. 1 is a kind of overall structure schematic diagram of an embodiment of the multi-tower suspension bridge reinforcement structure that is used to overcome middle tower effect of the present invention;

Fig. 2 is a structural representation of the first central buckle in an embodiment of a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention;

Fig. 3 is a schematic diagram of the connection structure between the mid-span position of the main cable and the central buckle assembly in an embodiment of a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention;

Fig. 4 is a structural schematic diagram of the suspender and the main girder connection in an embodiment of a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention;

Figure 5 is a schematic diagram of main span force analysis when the suspension bridge does not use a multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect of the present invention;

Fig. 6 is the main span stress analysis schematic diagram when the suspension bridge uses a kind of multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect of the present invention;

In the figure: 1, central buckle assembly, 11, first central buckle, 111, welding groove, 112, welding handle, 12, second central buckle, 13, connecting rod, 14, compensation cable, 15, third central buckle, 16, the fourth central buckle, 2, the main beam, 21, the foundation column, 22, the anchor ring, 3, the main cable, 31, the bolt ball, 4, the middle tower, 5, the side tower, 6, the boom.

Detailed ways

The following are specific examples of the present invention to further describe the technical solution of the present invention, but the present invention is not limited to these examples.

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement and steps of the modules and steps set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

At the same time, it should be understood that, for the convenience of description, the processes in the drawings are not only performed individually, but multiple steps are performed intersecting with each other.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the product of the present invention is used, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying References to devices or elements must have a particular orientation, be constructed, and operate in a particular orientation and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are only used for distinguishing descriptions, and should not be construed as indicating or implying relative importance.

The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses.

Technologies, methods and systems known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods and systems should be considered part of the authorized description.

Embodiment 1: As shown in Figures 1 to 6, it is only one of the embodiments of the present invention, a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect, including a mid-tower 4, a side tower 5, for connecting The main cable 3 at the top of the middle tower 4 and the top of the side tower 5, the main beam 2 for connecting the bottom of the middle tower 4 and the bottom of the side tower 5, and the central buckle for connecting the main cable 3 and the main beam 2 Assembly 1, the central buckle assembly 1 includes a first central buckle 11 and a second central buckle 12, both of which are I-shaped pieces, and the first central buckle 11 and the second central buckle 12 are I-shaped pieces. The upper ends of the second central buckle 12 are all connected to the mid-span position of the main cable 3, and several suspenders 6 are connected between the main cable 3 and the main girder 2, and the mid-span position of the main cable 3 is close to the mid-span position. The connection between the suspender 6 on one side of the tower 4 and the main beam 2 is connected to the lower end of the first central buckle 11, and the main cable 3 spans the suspender 6 on the side close to the side tower 5 The connection with the main beam 2 is connected with the lower end of the second central buckle 12 .

In the present invention, we only illustrate the structural reinforcement between the middle tower 4 and a side tower 5 on one side in the three-tower suspension bridge structure. The main cable 3 connects the top of the middle tower 4 and the top of the side tower 5, and the main cable 3 The mid-span position sags under gravity; the main girder 2 is the horizontal main girder of the entire suspension bridge. In order to prevent the main cable 3 from shaking, some suspenders 6 (or slings) and the main girder 2 will hang down on the main cable 3 For flexible connection, we install the central buckle assembly 1 at the mid-span position of the main cable 3 to connect with the main beam 2.

Here, the central buckle assembly 1 includes a first central buckle 11 and a second central buckle 12, the upper ends of the first central buckle 11 and the second central buckle 12 are connected to the mid-span position of the main cable 3, so Several suspenders 6 are connected between the main cable 3 and the main girder 2, and the suspender 6 on the side of the mid-span position of the main cable 3 close to the middle tower 4 and the junction of the main girder 2 and the The lower end of the first central buckle 11 is connected, and the suspender 6 on the side near the side tower 5 and the joint of the main beam 2 of the main cable 3 are connected with the lower end of the second central buckle 12, In this way, the first central buckle 11, the second central buckle 12, and the section of main beam 2 between the bottom end of the first central buckle 11 and the second central buckle 12 form a triangular truss structure, so that the whole central buckle assembly 1 is more structured. High, and due to the stability of the triangular structure, the longitudinal and lateral displacements of the main cable 3 mid-span are limited, which effectively increases the strength of the entire central buckle assembly, has a long service life, and can effectively improve the stiffness of the multi-tower suspension bridge.

In order to illustrate the effect of a multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect of the present invention, the force analysis of the suspension bridge is carried out (the left span is taken as an example below):

When a kind of multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect of the present invention is not used, as shown in Figure 5, the multi-tower suspension bridge lacks the constraint of the side-span main cable due to the middle tower 4, and the main cable 3 pairs of intermediate bridge towers The constraints are weak, and the stiffness of the middle tower 4 is low; when the most unfavorable load is applied, that is, the main span is fully loaded q, the tops of the side tower 5 and the middle tower 4 move toward the mid-span, and the position A of the top of the side tower 5 moves to A' , the top position B of the middle tower 4 is displaced to B', at this time, the horizontal force H2 on the top of the side tower 5 is equal to the horizontal force H1 on the top of the middle tower 4; the main beam 2 produces vertical deflection, and the main span 3 The position C moves down to C', and the lower stiffness of the middle tower 4 causes more displacement at the top of the tower, that is, AA' is smaller than BB', so that the peak value of the vertical deflection of the main beam is larger, that is, δ1 is greater than the mid-span deflection δ2, and the deflection The peak is no longer the mid-span;

Conversely, when using a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention, as shown in Figure 6, after the mid-span of the main cable 3 is connected to the main girder 2 through the central buckle assembly 1, it is equivalent to the main Beam 2 constrains the middle span of main cable 3. When the most unfavorable load is also applied, that is, the full load q of the main span, although the middle tower 4 still has more displacement than the side tower 5, because the central buckle assembly 1 restricts the main cable 3 In relation to the longitudinal displacement, the deflection increment caused by the more displacement of the middle tower 4 than that of the side tower 5 is not as much as when no reinforcement structure is used. The lateral displacement of the mid-span position of the main cable 3 is limited, so the horizontal force H2 on the top of the side tower 5 is equal to the horizontal force H1 on the top of the middle tower 4 and the mid-span position of the main cable 3 (that is, the central buckle assembly 1). The sum of the horizontal force H3, that is, the horizontal force H1 on the top of the middle tower 4 is partially borne by the main beam 2 connected to the central buckle assembly 1;

In a word, after using a multi-tower suspension bridge reinforcement structure for overcoming the middle tower effect of the present invention, not only the peak value of the longitudinal deflection is reduced, but also the horizontal force received by the middle tower 4 is also shared by the main girder 2. It can be known that the present invention can Effectively overcome the mid-tower effect, and can also have high resistance to horizontal deflection increments. Even if the main span is fully loaded, the safety of the cable bridge is still guaranteed.

A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention has simple structure and low installation cost. A central buckle assembly is installed in the main cable span, and two central buckle components in the central buckle assembly form a triangle with a section of the main girder. The truss can effectively increase the strength of the entire central buckle assembly, can effectively improve the stiffness of the multi-tower suspension bridge, and has high resistance to horizontal deflection increments. Even if the main span is fully loaded, the safety of the cable bridge is still guaranteed, and the stability of the central buckle assembly Well, long life.

Embodiment 2, still shown in Figures 1 to 6, is only one of the embodiments of the present invention. On the basis of Embodiment 1, in a multi-tower suspension bridge reinforcement structure used to overcome the middle tower effect of the present invention, the The first central buckle 11 and the second central buckle 12 have the same length, that is, it is best to make the triangular truss an isosceles triangle structure, so that the material selection is more uniform, and the first central buckle 11 and the second central buckle 12 are 3-span for the main cable. The stress sharing in the bridge is more balanced, and the strength of the suspension bridge is higher.

Certainly, the middle part of the first central buckle 11 is connected to the middle part of the second central buckle 12 through the connecting rod 13, that is, the upper half of the first central buckle 11, the upper half of the second central buckle 12 and the connecting rod 13 form a A small triangular truss, and the small triangular truss is similar to the large triangular truss, can increase the structural strength of the large triangular truss, and can also connect the first central buckle 11 and the second central buckle 12, then when the first central When the buckle 11 is stressed, the second central buckle 12 can carry out synchronous sharing.

Furthermore, the lower end of the first central buckle 11 is connected to the bottom of the second central buckle 12 through a compensation cable 14, where the height of the compensation cable 14 is not lower than the height of the main girder 2, and The mid-span position of the compensation cable 14 is connected to the end of the connecting rod 13 through the third central buckle 15, and the mid-span position of the compensation cable 14 is far away from the third central position through the fourth central buckle 16 and the connecting rod 13. One end of buckle 15 is connected.

The mid-span of the compensation cable 14 is bent upward by the pulling force of the third central buckle 15 and the fourth central buckle 16 to compensate for the extension of the main cable 3, and the third central buckle 15, the fourth central buckle 16 and the connecting rod 13 are also formed A triangular structure is used to strengthen the connection strength of the connecting rod 13, further enabling the first central buckle 11 and the second central buckle 12 in the central buckle assembly to form mutual compensation.

Finally, the first central buckle 11, the second central buckle 12, the third central buckle 15 and the fourth central buckle 16 are all rigid I-pieces, ensuring the rigid connection of the central buckle assembly 1. Under the I-piece structure, The end area of the central buckle is larger, which is more convenient for the central buckle to be welded and connected.

Embodiment 3, still shown in Figures 1 to 6, is only one of the embodiments of the present invention. On the basis of any of the above embodiments, the present invention is used in a multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect. The center position of the main cable 3 is provided with a bolt ball 31 for connecting with the central buckle assembly 1, and the ends of the first central buckle 11 and the second central buckle 12 are provided with bolt balls 31 for connecting Welded welding groove 111; at least a part of the bolt ball 31 snaps into the welding groove 111. After selecting the first central buckle 11 and the second central buckle 12 of appropriate length to complete the cooperation with the mid-span position of the main cable 3, the main cable The bolt ball 31 at the mid-span position of the cable 3 snaps into the welding groove 111 to complete the welding.

Similarly, an anchor ring 22 is provided at the joint between the suspender 6 and the main beam 2, the end of the first central buckle 11 away from the welding groove 111 and the end of the second central buckle 12 away from the welding groove 111 One end is provided with a welding handle 112 for welding with the anchor ring 22 , and after the welding handle 112 is inserted into the anchor ring 22 , the welding handle 112 and the anchor ring 22 are welded.

Finally, the lower side of the main girder 2 is provided with a foundation column 21 for connecting with the middle tower 4 and the side tower 5. To be precise, none of the main towers (including the middle tower 4 and the side tower 5) are integrally connected below There is a foundation column 21, and the foundation column 21 is a reinforced concrete column arranged on the ground, and the main beam 3 is horizontally arranged at the intersection of the main tower and the foundation column 21.

A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect of the present invention has simple structure and low installation cost. A central buckle assembly is installed in the main cable span, and two central buckle components in the central buckle assembly form a triangle with a section of the main girder. The truss can effectively increase the strength of the entire central buckle assembly, effectively improve the stiffness of the multi-tower suspension bridge, and has high resistance to horizontal deflection increments. Even if the main span is fully loaded, the safety of the cable bridge is still guaranteed. Adding a compensation cable to the top further enables the two central buckles in the central buckle assembly to form mutual compensation, which effectively reduces the wear of the central buckle assembly, has a long service life, and reduces maintenance costs.

The present invention is not limited to the specific embodiments described above, and various modifications and changes are possible in the present invention. Any modifications, equivalent replacements, improvements, etc. made to the above implementation methods based on the technical essence of the present invention shall be included in the protection scope of the present invention.

Claims (6)

1. A multi-tower suspension bridge reinforcement structure for overcoming middle tower effect, is characterized in that: comprise middle tower (4), side tower (5), be used to connect described middle tower (4) top and side tower (5) ) the main cable (3) at the top, the main beam (2) used to connect the bottom of the middle tower (4) and the bottom of the side tower (5), and the main cable (3) and main beam (2) used to connect The central buckle assembly (1), the central buckle assembly (1) includes a first central buckle (11) and a second central buckle (12), the first central buckle (11) and the second central buckle (12) Both are I-shaped parts, the upper ends of the first central buckle (11) and the second central buckle (12) are connected to the mid-span position of the main cable (3), and the main cable (3) and the main beam There are several suspenders (6) connected between (2), the suspender (6) on the side of the middle tower (4) and the main girder (2) at the mid-span position of the main cable (3) The connection point is connected to the lower end of the first central buckle (11), and the main cable (3) spans the suspender (6) and the main girder (2) on the side close to the side tower (5). ) connection is connected with the lower end of the second central buckle (12); the length of the first central buckle (11) and the second central buckle (12) are the same; the middle part of the first central buckle (11) is connected by The rod (13) is connected to the middle of the second central buckle (12); the bottom end of the first central buckle (11) is connected to the bottom of the second central buckle (12) through a compensation cable (14); the compensation The height of the cable (14) is not lower than the height of the main beam (2), and the mid-span position of the compensation cable (14) is connected to the end of the connecting rod (13) through the third central buckle (15), The mid-span position of the compensation cable (14) is connected to the end of the connecting rod (13) away from the third central buckle (15) through the fourth central buckle (16). 2. A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect according to claim 1, characterized in that: the third central buckle (15) and the fourth central buckle (16) are I-shaped pieces . 3. A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect according to claim 2, characterized in that: the first central buckle (11), the second central buckle (12), and the third central buckle (15) and the 4th central buckle (16) all are rigid parts. 4. A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect according to claim 1, characterized in that: the mid-span position of the main cable (3) is provided with the central buckle assembly (1) For the connected bolt ball (31), the ends of the first central buckle (11) and the second central buckle (12) are provided with welding grooves (111) for welding with the bolt ball (31). 5. A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect according to claim 4, characterized in that an anchor ring ( 22), the end of the first central buckle (11) away from the welding groove (111) and the end of the second central buckle (12) away from the welding groove (111) are both provided with anchor rings ( 22) Welding handle (112) for welding. 6. A multi-tower suspension bridge reinforcement structure for overcoming the mid-tower effect according to claim 1, characterized in that: the underside of the main girder (2) is provided with a The tower (5) is connected to the foundation column (21).

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