Cable-stayed bridge with high and low towers

Abstract

A main bridge of the cable-stayed bridge comprises a low tower, a high tower, a main beam and a stay cable, the low tower and the high tower are arranged in the longitudinal direction of the bridge, the main bridge is divided into a first side span, a middle span and a second side span which are sequentially arranged, the main beam is supported on the low tower and the high tower, and the stay cable is supported on the middle span. The main beam is arranged between the low tower and the high tower and is divided into a main beam weight area located in a side span and a main beam standard section located in a main span by the low tower and the high tower, a vertical support is arranged between the low tower and the main beam, and the high tower and the main beam are fixedly connected through tower beam piers, so that the main bridge forms a'consolidation + semi-floating 'structural system; the low tower and the high tower adopt single-column type bridge towers in the transverse bridge direction, the vertical surface of the appearance is in a swan neck shape, a lower tower column adopts a variable cross-section straight line form, an upper tower column adopts a uniform cross-section section, and the uniform cross-section section of the upper tower column in the bridge direction adopts a circular curve shape in the vertical direction. According to the scheme, the structure is attractive, the structure is reasonable, and design and construction are convenient.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of cable-stayed bridges, in particular to a high-low tower cable-stayed bridge. BACKGROUND

[0002] The main structure of the cable-stayed bridge is a combined structural system composed of three basic components, namely, a tower, a beam and a cable. The effect of the cable is equivalent to adding a number of elastic supports in the main beam span, thereby greatly reducing the bending moment in the beam and the size of the beam body, and significantly increasing the bridge crossing capacity.

[0003] With the development of the economy and society, the landscape requirements of bridge construction are continuously improved, and the special-shaped cable-stayed bridge with better landscape is gradually applied. In addition, under certain conditions of topography, geology and navigation, the high-low tower cable-stayed bridge has better adaptability. According to different construction conditions and construction requirements, the scheme selection of the special-shaped cable-stayed bridge is diversified, and it is a process of continuous iteration and optimization. For such a structure, due to the asymmetry of the bridge tower and the special shape of the structure, the stress of the structure is more complex than that of the conventional cable-stayed bridge structure. If the structure system, main structure and details are not properly handled, it will bring great difficulties to the design and construction, and affect the effect of the completed project.

[0004] Therefore, it is necessary to optimize and improve the structure of the special-shaped cable-stayed bridge to facilitate the design and construction and improve the rationality and aesthetics of the bridge system. CONTENT OF THE UTILITY MODEL

[0005] The utility model solves the technical problem of providing a high-low tower cable-stayed bridge with beautiful modeling and reasonable structure.

[0006] To solve the above technical problems, the utility model adopts the following technical scheme:

[0007] A high-low tower cable-stayed bridge, comprising a low tower, a high tower, a main beam and a cable, wherein the low tower and the high tower are arranged along the longitudinal direction of the bridge, dividing the main bridge into a first side span, a middle span and a second side span arranged in sequence, the main beam is supported on the low tower and the high tower, and is divided into a main beam deadweight area located in the side span and a main beam standard section located in the main span by the low tower and the high tower, vertical supports are arranged between the low tower and the main beam, and the high tower and the main beam are fixed by a tower beam pier, so as to form a "fixed + semi-floating" structural system of the main bridge.

[0008] The low tower and the high tower adopt a single-column bridge tower in the transverse direction of the bridge, the appearance elevation is in the shape of a swan's neck, the lower tower column adopts a variable cross-section straight line form, the upper tower column adopts an equal cross-section section, and the upper tower column equal cross-section section in the longitudinal direction of the bridge adopts a circular curve shape.

[0009] The utility model scheme has beautiful modeling and reasonable structure, facilitates the design and construction, and realizes the unity of mechanics and aesthetics.

[0010] Preferably, the vertical support includes corbels symmetrically arranged on the low tower and a vertical support horizontal movable support arranged between the main beam and the corbels.

[0011] Preferably, the vertical support horizontal movable support includes a two-way movable support and a one-way movable support.

[0012] Preferably, a transverse wind-resistant support is also provided between the low tower and the main beam.

[0013] Preferably, the main towers of the low tower and the high tower are made of reinforced concrete, and the tower crowns are made of steel.

[0014] Preferably, with the longitudinal bridge pointing upwards, the middle span of the tower crown continues the circular curve shape of the upper tower column to the top of the tower, while the side span adopts a three-segment straight line change; with the transverse bridge pointing upwards, the tower crown transitions in a straight line-circular arc-straight line manner.

[0015] Preferably, in terms of construction, the tower crowns of the low tower and the high tower adopt a single-box welded steel structure section, and the lower part is provided with a pressure plate connected to the reinforced concrete main tower. The tower crown and the main tower are connected by shear studs and anchor bolts.

[0016] Preferably, vertical support horizontal movable supports are also provided at both ends of the main beam.

[0017] Preferably, the main beam is a prestressed concrete structure with a single-box five-cell cross-section structure with inclined web, and the standard segment length of the main beam on the lower tower side is less than the standard segment length of the main beam on the higher tower side.

[0018] Preferably, solid crossbeams are provided at both ends of the main beam, and counterweights are provided in the box girder of the side span of the main beam.

[0019] The bridge design of this utility model is a double-cable-stayed bridge with a central double-tower structure and a high and low tower. The overall design highlights the theme of "swan", and the bridge towers (low tower and high tower) are curved towers.

[0020] Regarding the selection of the structural system, since the overall structure of the bridge of this utility model is an irregular cable-stayed bridge with high and low curved towers, the effects of dead load on both sides are asymmetrical, requiring longitudinal fixed constraints. Considering the poor suitability of floating and semi-floating systems, rigid frame systems have the advantage of not needing to set supports and temporary construction consolidation, but are suitable for flexible piers with higher lower towers; otherwise, they will bring significant temperature and shrinkage creep effects. Tower-beam consolidation (tower-pier separation) systems require large-tonnage supports, have low overall stiffness, and are not suitable for large-span structures. Therefore, after research and comparison, the inventors adopted a high-tower consolidation and low-tower semi-floating system structure in this utility model, with openings in the main beam at the low tower to pass through the tower column, and corbels and supports set on both sides of the bridge tower to provide vertical support for the main beam.

[0021] The main structure of the bridge towers is made of reinforced concrete. The lower tower adopts a variable cross-section straight shape, which is beneficial to the structural stress. The upper tower column has a uniform cross-section section with a circular curve shape in the vertical direction along the bridge, which facilitates design and construction. Adjustment of cable tension is used to optimize the structural stress of the curved bridge tower. The tower crown adopts a simplified swan head shape and is prefabricated and installed using steel structures. The ring prestressing of the cable anchorage section adopts the U-shaped steel strand tension method, and vertical prestressed steel strands are arranged at the top of the tower column to improve the local stress at the top of the tower.

[0022] The tower crown of the cable-stayed bridge adopts a simplified swan head shape. Structurally, it uses a single-box welded steel structure section, with a bearing plate at the bottom connecting to the concrete tower. The steel tower crown is connected to the lower concrete tower column using shear studs and anchor bolts. Considering construction and hoisting conditions, the tower crown steel structure is fabricated in sections and installed segment by segment using a hoisting method, with welded connections between sections.

[0023] To facilitate construction, the main girder of the cable-stayed bridge is a prestressed concrete structure constructed in a cantilever configuration, with a cross-section of a single-box, five-cell structure with inclined webs. The main girder is designed with a three-dimensional prestressing system, with longitudinal prestressing divided into pre-construction tendons and closure tendons. To improve structural stress distribution, counterweights are installed in the box ducts at the side spans of the main girder. The counterweights are made of precast iron sand concrete blocks, and the arrangement of counterweights in each box duct is based on calculation requirements. To meet lateral stress and structural counterweight requirements, solid crossbeams are installed at both ends of the main girder, with the bottom of the end crossbeams raised.

[0024] To meet aesthetic and structural requirements, the stay cables are arranged in a central double-plane fan shape. The stay cables are tensioned at one end, with the anchorage end on the tower; concrete anchor blocks are installed at the cable anchorage positions on the beam, serving as the tensioning ends. The stay cable body is composed of multiple strands of unbonded, high-strength parallel galvanized steel strands, with an outer HDPE sheath, allowing for single-strand tensioning during construction and operation / maintenance.

[0025] Compared with the prior art, the beneficial effects of this utility model are:

[0026] 1) This utility model adopts a "consolidated + semi-floating" cable-stayed bridge structural system, which reduces shrinkage, creep and temperature effects while ensuring structural rigidity;

[0027] 2) The bridge tower of this utility model adopts a simple swan-shaped curved tower and uses a combination of concrete body and steel structure tower crown, which takes into account both mechanics and aesthetics, and facilitates construction.

[0028] 3) The main beam of this utility model adopts a counterweight and crossbeam counterweight method, combined with cable force optimization and adjustment, to achieve a reasonable overall structure and reliable construction;

[0029] 4) The present invention has good scalability. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the overall bridge layout structure provided in an embodiment of the present utility model;

[0032] Figure 2 The schematic diagram of the bridge structure system provided in the embodiment of this utility model is shown in the figure. In the figure, a is an elevation view, b is a top view, SX represents a bidirectional movable support, and DX represents a unidirectional movable support.

[0033] Figure 3 This is a schematic diagram of the longitudinal bridge elevation of the general structure of the low tower of this utility model;

[0034] Figure 4 This is a schematic diagram of the general structure of the low tower of this utility model from the transverse bridge direction.

[0035] Figure 5 This is a schematic diagram of the longitudinal bridge elevation of the general structure of the high tower of this utility model;

[0036] Figure 6 This is a longitudinal elevation view of the general structure of the tower crown of a high or low tower according to this utility model.

[0037] Figure 7 This is a cross-sectional schematic diagram of the reinforced concrete bridge tower of this utility model;

[0038] Figure 8 This is a schematic diagram of the vertical prestressing at the top of the tower according to this utility model;

[0039] Figure 9 This is a schematic diagram of the standard cross-section of the main beam of this utility model;

[0040] Figure 10 This is a schematic diagram of the crossbeam at the side end of the approach bridge of this utility model;

[0041] Figure 11 This is a schematic diagram of the crossbeam at the side end of the bridge abutment of this utility model;

[0042] Figure 12 This is a schematic diagram of the counterweight for the side span of the main beam of this utility model.

[0043] In the picture:

[0044] 1 — Low tower;

[0045] 2 — Lower tower crown;

[0046] 3 — Tower;

[0047] 4 — The crown of the tower;

[0048] 5 — Beef leg;

[0049] 6 — Standard section of main beam;

[0050] 7 — Main beam counterweight zone;

[0051] 8 — Approach bridge side end crossbeam;

[0052] 9 — Crossbeam at the side end of the bridge abutment;

[0053] 10 — Cable stays;

[0054] 11 — Vertical support for horizontal movable support;

[0055] 12 — Lateral wind-resistant support;

[0056] 13 — Tower-beam-pier consolidation;

[0057] 14 — Lower tower column;

[0058] 15 — Upper Tower Column;

[0059] 16 — Compression. Detailed Implementation

[0060] The present invention will be further described below with reference to specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0061] In the description of this utility model, it should be noted that the terms "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0062] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0063] like Figure 1 As shown, the main bridge structure of an embodiment of the high-low tower cable-stayed bridge of this utility model includes a low tower 1, a high tower 3, a main beam, and cable stays 10. The low tower 1 and the high tower 3 are arranged sequentially in the middle of the bridge along the longitudinal direction. The main beam rests on the low tower 1 and the high tower 3, and cable stays 10 are installed on both sides of the low tower 1 and the high tower 3 to connect with the main beam. The main beam is divided by the low tower 1 and the high tower 3 into a standard section 6 of the main beam located in the middle span B and a main beam counterweight zone 7 located in the first side span A and the second side span C. The spans of the first side span A, the middle span B, and the second side span C are 70 m, 192 m, and 110 m, respectively.

[0064] The main bridge adopts a "fixed + semi-floating" structural system, meaning that a tower-beam pier is used for fixed connection at the high tower 3, and vertical supports are provided at the low tower 1. In terms of support arrangement, vertically supported horizontal movable supports 11 are installed on the corbel 5 at the low tower 1, and lateral wind-resistant supports 12 are also installed at the low tower to resist the lateral effects of wind and seismic loads on the main beam. Vertically supported horizontal movable supports 11 are also installed at both ends of the main beam, such as... Figure 2 In the diagram, SX represents a bidirectional movable support, and DX represents a unidirectional movable support.

[0065] like Figure 3 - Figure 8 As shown, the main tower (including low tower 1 and high tower 3) adopts a single-column bridge tower in the transverse direction of the bridge, and its appearance facade is shaped like a swan's neck. The lower tower column 14 adopts a variable cross-section straight form, and the upper tower column 15 adopts a circular curve shape in the longitudinal direction of the bridge with a constant cross-section. The total height of low tower 1 is 83.0m (excluding the tower base), and the total height of high tower 3 is 102.59m (excluding the tower base). The main structure of the main tower is made of C50 reinforced concrete, and the crowns of low tower 2 and high tower 4 are made of Q235B steel.

[0066] The standard cross-section of the upper column of the lower tower 1 is a rectangle of 440cm × 350cm. A corbel 5 and a vertical support horizontal movable bearing 11 for supporting the main beam are installed at the bottom of the beam. The standard cross-section of the upper column of the higher tower 3 is a rectangle of 500cm × 380cm. The crowns of the lower tower 2 and the higher tower 4 adopt simplified swan head shapes. The design concept of crown 2: longitudinally, a circular curve continues from the middle span to the top of the tower, while the side spans adopt a three-segment straight line transition; transversely, a straight line-circular arc-straight line transition is used. Structurally, crown 2 adopts a single-box welded steel structure cross-section, with a total height of 12m. A bearing plate is installed at the bottom to connect with the reinforced concrete main tower. The crown is connected to the lower concrete main tower using shear studs and anchor bolts. Considering construction and hoisting conditions, the steel structure of the crown is fabricated in sections and installed segment by segment using a hoisting method, with welded connections between sections.

[0067] The annular prestressing of the cable-stayed cable anchorage section adopts the U-shaped steel strand tension method, with 15 φs15.2 steel strand bundles arranged in each hole. Deep-buried anchoring is used, paired with YM15-15 DHS low-retraction anchors. During construction, circular tower-shaped anchor plates and steel sleeves are pre-embedded. The top of the tower is equipped with 12 φs15.2mm vertical prestressing strands, fitted with YM15-12 anchors.

[0068] like Figure 9 As shown, the main beam is a prestressed concrete structure using C55 concrete, with a single-box, five-cell cross-section and inclined web. The beam height is 2.6m, with the cable-stayed section raised to 2.85m to improve local stress distribution. The main beam is constructed using cantilever casting. To coordinate structural stress and construction progress, the standard segment length is 6m on the lower tower side and 8m on the higher tower side. The main beam is constructed in-situ using pier-side supports on the tower side. At the lower tower location, the main tower passes through the top and bottom slabs of the main beam, requiring temporary pier-side supports. A 15m scaffolded section is provided for the side spans; during construction, the side spans are closed first, followed by the middle span.

[0069] like Figure 1 and Figure 10 , Figure 11 As shown, to meet the requirements of lateral force and increase the counterweight of the side spans, solid crossbeams are installed at both ends of the main beam, such as... Figure 1 The approach bridge side end crossbeam 8 and abutment side end crossbeam 9 are constructed, with their bottoms heightened. The bottom of the end crossbeams is widened from the original box girder bottom width to facilitate the placement of supports, enhance lateral torsional resistance, and reserve space for prestressed anchorage of the crossbeams. Prestressing is installed inside the crossbeams, using φs15.2mm type steel strands as calculated.

[0070] like Figure 12 As shown, a counterweight 16 is installed in the box girder compartment at the side span of the main beam. The counterweight 16 is made of 0.3×0.3×0.3m precast iron sand concrete blocks with a design density of 40kN / m³. 3 The chamber is weighed down according to the calculation requirements.

[0071] This utility model is applicable to cable-stayed bridge structures with different shapes of high and low towers. According to the solution provided by this utility model, it can also be extended to similar curved bridge tower cable-stayed bridge structures.

[0072] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can make many possible variations and modifications to the technical solution of this utility model, or modify it into equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of this utility model. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from the content of the technical solution of this utility model should fall within the protection scope of the technical solution of this utility model.

Claims

1. A high-low tower cable-stayed bridge, comprising a low tower, a high tower, a main girder, and cable stays, characterized in that: The low tower and the high tower are arranged along the longitudinal direction of the bridge, dividing the main bridge into a first side span, a middle span and a second side span arranged in sequence. The main beam is supported on the low tower and the high tower, and is divided by the low tower and the high tower into a main beam counterweight zone located in the side span and a main beam standard section located in the main span. Vertical supports are set between the low tower and the main beam, and the high tower is fixed to the main beam by tower-beam-pier, so that the main bridge forms a "fixed + semi-floating" structural system. The low tower and the high tower adopt single-column bridge towers in the transverse direction, with an appearance facade resembling a swan's neck. The lower tower column adopts a variable cross-section straight form, while the upper tower column adopts a constant cross-section section. Furthermore, the constant cross-section section of the upper tower column in the longitudinal direction adopts a circular curve shape vertically.

2. The high-low tower cable-stayed bridge according to claim 1, characterized in that, The vertical support includes corbels symmetrically arranged on the low tower and a vertical support horizontal movable support arranged between the main beam and the corbels.

3. The high-low tower cable-stayed bridge according to claim 2, characterized in that, The vertical support horizontal movable support includes a two-way movable support and a one-way movable support.

4. The high-low tower cable-stayed bridge according to claim 1, characterized in that, A transverse wind-resistant support is also provided between the low tower and the main beam.

5. The high-low tower cable-stayed bridge according to claim 1, characterized in that, The main towers of both the low tower and the high tower are made of reinforced concrete, and the tower crowns are made of steel.

6. The high-low tower cable-stayed bridge according to claim 5, characterized in that, As the longitudinal bridge extends upwards, the central span of the tower crown continues the circular curve shape of the upper tower column to the top of the tower, while the side spans adopt a three-segment straight line change; as the transverse bridge extends upwards, the tower crown transitions in a straight line-circular arc-straight line manner.

7. The high-low tower cable-stayed bridge according to claim 5, characterized in that, In terms of construction, the crowns of the low tower and the high tower adopt a single-box welded steel structure section, and the lower part is provided with a pressure plate connected to the reinforced concrete main tower. The crowns and the main tower are connected by shear studs and anchor bolts.

8. The high-low tower cable-stayed bridge according to claim 2, characterized in that, The main beam is also equipped with vertical support and horizontal movable supports at both ends.

9. The high-low tower cable-stayed bridge according to claim 1, characterized in that, The main beam is a prestressed concrete structure with a single-box five-cell cross-section structure with inclined webs, and the standard segment length of the main beam on the lower tower side is less than that on the higher tower side.

10. The high-low tower cable-stayed bridge according to claim 1, characterized in that, Solid crossbeams are installed at both ends of the main beam, and counterweights are installed in the box girder of the side span of the main beam.

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