Construction method of hybrid girder cable-stayed bridge

Abstract

This invention relates to the field of construction technology for hybrid beam cable-stayed bridges, and provides a construction method for such bridges, comprising the following steps: moving the main beam frame of the side beams from the abutment towards the bridge tower until both ends of the main beam frame are connected to the abutment and the bridge tower respectively; installing the mid-span steel beam on the side of the bridge tower away from the abutment, and installing the first part of the side-span concrete on the side of the bridge tower facing the tower, wherein the weight of the first part of the side-span concrete matches that of the mid-span steel beam and is constructed symmetrically; pouring the mid-span bridge deck and the second part of the side-span concrete, wherein the weight of the mid-span bridge deck and the second part of the side-span concrete are matched and constructed symmetrically. Using this construction method for hybrid beam cable-stayed bridges solves the problem of existing hybrid beam cable-stayed bridge construction methods requiring the use of full-span scaffolding for side-span construction before mid-span construction due to the excessive weight of the side spans, resulting in long construction cycles and high risks.

Description

Technical Field

[0001] This invention relates to the field of construction technology for hybrid beam cable-stayed bridges, and in particular to a construction method for hybrid beam cable-stayed bridges. Background Technology

[0002] A hybrid beam cable-stayed bridge is a type of cable-stayed bridge where the side spans and the middle span use different materials. Typically, the middle span uses a steel main girder or a steel-concrete composite main girder, while the side spans use concrete main girders. Because the concrete in the side spans is heavier, the span ratio between the side and middle spans is generally 0.25 to 0.45 to maintain structural balance. Due to the relatively small spans in the side and middle spans, if cantilever symmetrical construction is used, the bridge towers are prone to overturning towards one end of the side span. Currently, the construction method for hybrid beam cable-stayed bridges is to first construct the concrete main girder of the side span in one go using a full-span scaffolding method to prevent the bridge towers from overturning or the side span from collapsing. Then, a bridge deck crane is used to install the middle span steel beams segment by segment, and finally, the middle span concrete bridge deck is poured and installed.

[0003] Because the existing hybrid beam cable-stayed bridge construction method requires constructing the side spans first, followed by the main concrete beams of the side spans, the construction period is long, generally adding about nine months compared to the cantilever symmetrical construction method. Furthermore, the one-time pouring of the concrete structure in the side spans is difficult, requiring thorough research and demonstration of the pouring sequence and concrete mix proportions; otherwise, the structure is prone to cracking after pouring. Simultaneously, since scaffolding needs to be erected to support the weight of the side spans, the existing hybrid beam cable-stayed bridge construction method must ensure that the scaffolding has sufficient strength and stability; otherwise, a problem in any part could lead to the collapse of the entire side span, posing a significant safety risk. Moreover, when the concrete bridge deck of the side span reaches a certain height above the ground, there are difficulties in erecting the scaffolding. Therefore, the existing hybrid beam cable-stayed bridge construction method is also easily limited by the geographical factors of the construction site, resulting in insufficient applicability. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that existing construction methods for hybrid beam cable-stayed bridges require the use of full-span scaffolding to construct the side spans before constructing the middle span due to the excessive weight of the side spans, resulting in long construction cycles and high risks. This invention provides a construction method for hybrid beam cable-stayed bridges.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A construction method for a hybrid beam cable-stayed bridge includes the following steps:

[0007] A. Move the side span main beam frame from the abutment toward the bridge tower; connect both ends of the side span main beam frame to the abutment and the bridge tower respectively; tension the stay cables corresponding to the side span main beam frame;

[0008] B. Install the mid-span steel beam on the side of the bridge tower away from the abutment; pour the first part of the side span concrete on the side of the bridge tower facing the abutment; the weight of the first part of the side span concrete matches the weight of the mid-span steel beam and is constructed symmetrically; tension the stay cables corresponding to the mid-span steel beam and the first part of the side span concrete respectively;

[0009] C. Pour the mid-span bridge deck and the second part of the side span concrete; the weight of the second part of the side span concrete matches the weight of the mid-span bridge deck and is constructed symmetrically; re-tension the stay cables corresponding to the mid-span steel beam and the first part of the side span concrete respectively;

[0010] Before step A, the construction of the bridge towers, auxiliary piers and abutments needs to be completed; the structural design of the bridge towers, auxiliary piers, abutments, stay cables and side spans and middle spans should refer to the existing hybrid beam cable-stayed bridges; the main beam skeleton of the side span should be designed as a structure that can be used as a basis for the first and second parts of the side span concrete pouring, such as setting a steel base plate on the main beam skeleton of the side span as a concrete pouring template.

[0011] The matching of the weight of the central span steel beam and the weight of the first part of the side span concrete means that the loads generated by the central span steel beam and the first part of the side span concrete on both sides of the bridge tower are equivalent, so that the bridge tower will not overturn due to the imbalance of loads on both sides. This allows the construction of the central span steel beam and the first part of the side span concrete to be carried out simultaneously on both sides of the bridge tower.

[0012] The weight matching of the mid-span bridge deck and the second part of the side span concrete means that the loads generated by the mid-span bridge deck and the second part of the side span concrete on both sides of the bridge tower are equivalent, so that the bridge tower will not overturn due to the unbalanced load on both sides. This allows the mid-span bridge deck and the second part of the side span concrete to be constructed simultaneously on both sides of the bridge tower.

[0013] The construction of the remaining parts of the hybrid beam cable-stayed bridge, such as asphalt paving and traffic safety measures, should refer to existing technologies.

[0014] The construction method of this hybrid beam cable-stayed bridge divides the side spans into the side span main beam skeleton, the first part of the side span concrete, and the second part of the side span concrete. The middle span is divided into the middle span steel beam and the middle span bridge deck. During construction, the side span main beam skeleton is first pushed from the abutment to the bridge tower and connected. Then, in subsequent construction, the first part of the side span concrete and the second part of the side span concrete are poured based on the side span main beam skeleton. During pouring, the weight of the first part of the side span concrete and the second part of the side span concrete are matched with the weight of the middle span steel beam and the middle span bridge deck, respectively, and the construction is symmetrical. This ensures that the bridge tower is always in a balanced state. There is no need to build a full-span scaffold under the side span to support the weight of the side span. Therefore, it can avoid the risk of side beam collapse due to partial failure of the side beam scaffold and avoid the situation where the construction of the side beam cannot be carried out due to the geographical environment.

[0015] Meanwhile, because the weight of the first part of the side span concrete matches that of the central span steel beam, and the weight of the second part of the side span concrete matches that of the central span bridge deck, this scheme can simultaneously carry out symmetrical construction of the central span steel beam and the first part of the side span concrete on both sides of the bridge tower, as well as symmetrical construction of the central span bridge deck and the second part of the side span concrete. This eliminates the time required by existing construction methods to wait for the side span concrete construction to be completed before constructing the central span, and thus can significantly shorten the construction cycle.

[0016] As a preferred embodiment of the present invention, the mid-span steel beam in step B is installed in segments along the length direction, and the first part of the side span concrete in step B is also poured in segments along the length direction, and the weight of the mid-span steel beam segment is matched with that of the first part of the side span concrete segment; the mid-span steel beam segment and the first part of the side span concrete segment are constructed symmetrically.

[0017] Symmetrical construction of the mid-span steel beam segments and the first part of the side span concrete means that for each mid-span steel beam segment poured, the corresponding first part of the side span concrete needs to be poured on the other side of the abutment, so as to maintain the load balance on both sides of the bridge tower.

[0018] This plan recommends dividing the mid-span steel beam and the first part of the side span concrete into several segments, which can reduce the volume of each concrete pour. This reduces the difficulty of pouring and the heat of hydration, lowers the temperature difference between the inside and outside of the concrete structure, and thus reduces cracking, which is conducive to obtaining higher pouring quality.

[0019] As a preferred embodiment of the present invention, the mid-span bridge deck in step C is poured in segments along the length direction, and the second part of the side span concrete in step C is also poured in segments along the length direction, and the weights of the mid-span bridge deck segments and the second part of the side span concrete segments are matched; the mid-span bridge deck segments and the second part of the side span concrete are constructed symmetrically.

[0020] Symmetrical construction of the mid-span bridge deck segment and the second part of the side span concrete means that for each mid-span bridge deck segment poured, the corresponding second part of the side span concrete segment needs to be poured on the other side of the abutment, so as to maintain the load balance on both sides of the bridge tower.

[0021] This plan recommends dividing the mid-span bridge deck and the second part of the side span concrete into several segments, thereby reducing the volume of each concrete pour. This reduces the difficulty of pouring and the heat of hydration, lowers the temperature difference between the inside and outside of the concrete structure, and reduces cracking, thus contributing to higher pouring quality.

[0022] As a preferred embodiment of the present invention, steps B and C are entirely replaced by the following steps:

[0023] S1. Install one section of the mid-span steel beam; pour one corresponding section of the first part of the side span concrete; tension the stay cables corresponding to the mid-span steel beam and the first part of the side span concrete, respectively;

[0024] S2. Cast the mid-span bridge deck segment corresponding to the mid-span steel beam segment; cast the side-span concrete second segment corresponding to the first segment of the side-span concrete; and re-tension the stay cables corresponding to the mid-span steel beam and the first segment of the side-span concrete, respectively.

[0025] S3. Repeat S1 and S2 until all mid-span bridge deck segments and the second part of the side span concrete segments are completed.

[0026] This plan recommends that each mid-span steel beam segment be installed after the mid-span bridge deck is poured. This allows construction equipment and personnel to be deployed and moved using the already poured mid-span bridge deck, facilitating the hoisting and splicing of the next mid-span bridge deck segment and improving construction efficiency.

[0027] As a preferred embodiment of the present invention, step A includes the following steps:

[0028] A1. Assemble the main beam frame of the side span in segments at the abutment;

[0029] A2. Push the side span main beam frame toward the top of the bridge tower;

[0030] A3. Repeat A1 and A2 until the side span main beam skeleton reaches the bridge tower; connect both ends of the side span main beam skeleton to the bridge abutment and the bridge tower respectively; tension the stay cables corresponding to the side span main beam skeleton.

[0031] This plan recommends dividing the main girder frame of the side span into several smaller segments and assembling and pushing them at the abutment. This can reduce the difficulty of manufacturing and transporting the main girder frame of the side span, as well as the difficulty of the pushing operation and the required construction site area.

[0032] As a preferred embodiment of the present invention, the following steps are included before step A:

[0033] A0. Construction jacking auxiliary pier; the jacking auxiliary pier is used to assist in supporting the side span main beam frame during the jacking operation of the side span main beam frame.

[0034] The specific location and number of auxiliary piers are determined based on the specific construction environment and actual needs, such as between two adjacent auxiliary piers.

[0035] This plan recommends constructing auxiliary jacking piers in front of the main beam frame of the side span to assist in the jacking operation, thereby increasing the support received by the main beam frame of the side span during the jacking operation, and thus reducing the overhang length and internal stress of the main beam frame of the side span during the jacking.

[0036] As a preferred embodiment of the present invention, after connecting the side span main beam skeleton and the bridge tower in step A, a balancing cable is connected to the side of the bridge tower away from the abutment; the balancing cable is used to balance the weight of the side span main beam skeleton.

[0037] The other end of the balancing cable can be connected to various locations, such as other bridge towers of a hybrid beam cable-stayed bridge or fixed structures on the ground.

[0038] This plan recommends adding a balancing cable on the other side of the bridge tower in step B, so as to ensure that the load on both sides is balanced when the bridge tower is connected to the main beam frame of the side span on one side, and to prevent the bridge tower from overturning.

[0039] As a preferred embodiment of the present invention, before moving the side span main beam frame in step A, a steel guide beam is connected to the side span main beam frame.

[0040] This plan recommends connecting steel guide beams to the side span main beam frame during the jacking process. This ensures stability when pushing the side span main beam frame and reduces the internal forces on the side span main beam frame when it is being pushed.

[0041] As a preferred embodiment of the present invention, after tensioning the stay cables in step A, outer concrete is poured at the joints between the main beam frame of the side span and the abutment, the bridge tower and the auxiliary pier respectively.

[0042] This plan recommends that after tensioning the stay cables in step A, an outer concrete layer be poured at the junction of the main beam frame of the side span with the abutment, tower and auxiliary pier respectively. On the one hand, this strengthens the connection between the main beam frame of the side span and the abutment, tower and auxiliary pier respectively. On the other hand, the outer concrete layer can act as a counterweight to reduce the vertical sway of the side beam when pouring the first part and the second part of the side beam concrete.

[0043] As a preferred embodiment of the present invention, a bridge deck crane is used when installing the mid-span steel beam.

[0044] This plan recommends using a bridge deck crane to lift the mid-span steel beams.

[0045] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0046] 1. The construction method of the hybrid beam cable-stayed bridge in this scheme divides the side spans into the side span main beam skeleton, the first part of the side span concrete, and the second part of the side span concrete. The middle span is divided into the middle span steel beam and the middle span bridge deck. During construction, the side span main beam skeleton is first pushed from the abutment to the bridge tower and connected. Then, in the subsequent construction, the first part of the side span concrete and the second part of the side span concrete are poured based on the side span main beam skeleton. During the pouring, the weight of the first part of the side span concrete and the second part of the side span concrete are matched with the weight of the middle span steel beam and the middle span bridge deck, respectively, and the construction is symmetrical. This ensures that the bridge tower is always in a balanced state. There is no need to build a full-span scaffold under the side span to support the weight of the side span. Therefore, it can avoid the risk of side beam collapse due to partial failure of the side beam scaffold and avoid the situation where the construction of the side beam cannot be carried out due to the geographical environment.

[0047] Meanwhile, because the weight of the first part of the side span concrete matches that of the central span steel beam, and the weight of the second part of the side span concrete matches that of the central span bridge deck, this scheme can simultaneously carry out symmetrical construction of the central span steel beam and the first part of the side span concrete on both sides of the bridge tower, as well as symmetrical construction of the central span bridge deck and the second part of the side span concrete. This eliminates the time required by existing construction methods to wait for the side span concrete construction to be completed before constructing the central span, and thus can significantly shorten the construction cycle.

[0048] 2. This scheme can further divide the mid-span steel beam and mid-span bridge deck into several segments along the length direction, and correspondingly divide the first part of the side span concrete and the second part of the side span concrete into several segments as well. This allows the mid-span bridge deck, the first part of the side span concrete and the second part of the side span concrete to be poured in batches, thereby reducing the pouring difficulty of the mid-span and side span and helping to obtain higher pouring quality. Attached Figure Description

[0049] Figure 1 This is a side view schematic diagram of the construction method of a hybrid beam cable-stayed bridge according to the present invention in step A0 state;

[0050] Figure 2 This is a side view of the construction method of a hybrid beam cable-stayed bridge according to the present invention at the beginning of step A;

[0051] Figure 3 This is a side view of the construction method of a hybrid beam cable-stayed bridge according to the present invention when the main beam skeleton of the side span reaches the bridge tower in step A;

[0052] Figure 4 This is a side view schematic diagram of the construction method of a hybrid beam cable-stayed bridge according to the present invention at the end of step A;

[0053] Figure 5 This is a side view schematic diagram of the construction method of a hybrid beam cable-stayed bridge according to the present invention in step B state;

[0054] Figure 6 This is a side view schematic diagram of the construction method of a hybrid beam cable-stayed bridge according to the present invention in step C state;

[0055] Figure 7 This is a side view schematic diagram of the construction method of a hybrid beam cable-stayed bridge according to the present invention at the end of step C;

[0056] Figure 8 This is a schematic cross-sectional view of the mid-span along the transverse plane of the bridge, which is used in the construction method of a hybrid beam cable-stayed bridge according to the present invention.

[0057] Figure 9 This is a schematic diagram of the cross-section of the side span along the transverse plane of the construction method of a hybrid beam cable-stayed bridge according to the present invention;

[0058] Figure 10 This is a schematic cross-sectional view of the main beam frame of the side span along the transverse plane, which is used in the construction method of a hybrid beam cable-stayed bridge according to the present invention.

[0059] Icons: 1-Bridge tower; 2-Auxiliary pier; 3-Bridge abutment; 4-Cable stay; 5-Side span main beam skeleton; 6-Side span concrete first part; 7-Side span concrete second part; 8-Mid-span steel beam; 9-Mid-span bridge deck; 10-Jumping auxiliary pier; 11-Balance cable; 12-Steel guide beam. Detailed Implementation

[0060] The present invention will now be described in detail with reference to the accompanying drawings.

[0061] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0062] Example 1

[0063] like Figures 1 to 7 As shown, the construction method for a hybrid beam cable-stayed bridge adopted in this invention includes the following steps:

[0064] Construction of bridge tower 1, auxiliary pier 2, and abutment 3:

[0065] like Figure 1 As shown, this step requires the construction of the foundation, bridge tower 1, auxiliary piers 2, and abutments 3 for the hybrid beam cable-stayed bridge; simultaneously, the side span main beam frame 5 can be prefabricated in the factory to save construction time; the side span main beam frame 5 is prefabricated in segments to reduce manufacturing and transportation difficulties; and the side span main beam frame 5 needs to be designed to facilitate the batch pouring of side beam concrete; for the side span main beam frame 5 used in this embodiment, as... Figure 6 As shown, it includes multiple steel-concrete composite pipes arranged along the longitudinal direction of the bridge and steel trusses arranged along the transverse direction of the bridge; a steel base plate is also provided on the top of the steel trusses, and longitudinal stiffening ribs with PBL keys are provided on the steel base plate.

[0066] This step also includes the following steps:

[0067] A0. Construction jacking auxiliary pier 10; The jacking auxiliary pier 10 is used to assist in supporting the side span main beam frame 5 during the jacking operation of the side span main beam frame 5; In this embodiment, the jacking auxiliary pier 10 is specifically set between two adjacent auxiliary piers 2 to reduce the overhang length of the side span main beam frame 5 when pushing it.

[0068] Construction of the side spans will then commence:

[0069] A. Push the side span main beam frame 5 from abutment 3 toward tower 1; connect both ends of the side span main beam frame 5 to abutment 3 and tower 1 respectively; tension the stay cables 4 corresponding to the side span main beam frame 5.

[0070] Specifically, step A includes the following steps:

[0071] A1. Assemble the main beam frame 5 of the side span in sections at 3 abutments;

[0072] A2. Push the side span main beam frame 5 toward the bridge tower 1; specifically, during the pushing operation, a steel guide beam 12 is also set on the side span main beam frame 5;

[0073] A3. Repeat A1 and A2 until the side span main beam skeleton 5 reaches the bridge tower 1; remove the steel guide beam 12, and connect both ends of the side span main beam skeleton 5 to the bridge abutment 3 and the bridge tower 1 respectively; tension the stay cables 4 corresponding to the side span main beam skeleton 5; then remove the jacking auxiliary pier 10; in this step, the balance cable 11 is also connected and tensioned on the side of the bridge tower 1 away from the bridge abutment 3, and the other end of the balance cable 11 is connected to another bridge tower 1; the balance cable 11 is used to balance the weight of the side span main beam skeleton 5;

[0074] After tensioning the stay cables 4 and balance cables 11, if the main beam frame 5 of the side span needs to be poured with concrete, it can be done at this time. In this embodiment, since the main beam frame 5 of the side span uses steel-concrete composite, the steel-concrete composite is poured in this step, and the prestressed steel strands in the steel-concrete composite are tensioned after the concrete inside the steel tube reaches the design strength. After the steel-concrete composite is poured, this step also includes the following steps:

[0075] A4. Concrete is poured at the joints between the main beam frame 5 and the abutment 3, tower 1, and auxiliary pier 2 of the side span. The concrete can strengthen the connection between the main beam frame 5 and the abutment 3, tower 1, and auxiliary pier 2, and also act as a counterweight to reduce the vertical sway of the side beam when pouring the first and second parts of the side beam concrete.

[0076] Symmetrical construction of the side spans and the middle span:

[0077] B. Install the mid-span steel beam 8 on the side of the bridge tower 1 away from the abutment 3; pour the first part of the side span concrete 6 on the side of the bridge tower 1 facing the abutment 3; match the weight of the first part of the side span concrete 6 with the weight of the mid-span steel beam 8; symmetrically tension the stay cables 4 corresponding to the mid-span steel beam 8 and the first part of the side span concrete 6.

[0078] Specifically, the mid-span structure used in this embodiment is as follows: Figure 8 As shown, it includes a mid-span steel beam 8 and a mid-span bridge deck 9; in this step, only the mid-span steel beam 8 is installed; the side span structure used in this embodiment is as follows. Figure 9 and Figure 10 As shown, it includes the main beam frame 5 of the side span and the concrete structure enclosing the main beam frame 5; the concrete structure is divided into the first part 6 of the side span concrete and the second part 7 of the side span concrete along the vertical direction. This step only pours the first part 6 of the side span concrete.

[0079] In this step, the installation of the mid-span steel beam 8 uses a bridge deck crane that can move along the longitudinal direction of the bridge; it should be noted that the symmetrical tensioning of the stay cables 4 should be carried out after the first part of the side span concrete 6 reaches the design strength;

[0080] C. Pour the mid-span bridge deck 9 and the second part of the side span concrete 7; the weight of the second part of the side span concrete 7 matches the weight of the mid-span bridge deck 9; and tension the stay cables 4 corresponding to the mid-span steel beam 8 and the first part of the side span concrete 6 symmetrically again.

[0081] It should be noted that the symmetrical tensioning of the stay cables 4 should be carried out after the second part of the side span concrete 7 and the mid-span bridge deck 9 have reached the design strength.

[0082] D. Complete the construction of the hybrid beam cable-stayed bridge. Specifically, this step includes the following steps:

[0083] D1. After all the concrete structures have reached their design strength, tension the prestressed steel strands in the side span main beam skeleton 5 and the middle span bridge deck 9.

[0084] D2. Remove balance cable 11;

[0085] D3. Remaining structures for construction of hybrid beam cable-stayed bridges, such as asphalt paving and traffic safety measures;

[0086] D4. All stay cables 4 are tensioned again.

[0087] Example 2

[0088] Based on Example 1, in step B, the mid-span steel beam is divided into different segments along its length and installed segment by segment; in step B, the first part of the side span concrete is also divided into different segments corresponding to the mid-span steel beam and poured segment by segment; the mid-span steel beam segments and the first part of the side span concrete segments are constructed symmetrically.

[0089] Correspondingly, in step C, the mid-span bridge deck is divided into different segments along the length direction and poured segment by segment. The segment division of the mid-span bridge deck corresponds to the segment division of the mid-span steel beam. In step C, the second part of the side span concrete is also divided into different segments along the length direction and poured segment by segment. The segment division of the second part of the side span concrete corresponds to the segment division of the first part of the side span concrete. The mid-span bridge deck segments and the second part of the side span concrete are constructed symmetrically.

[0090] Furthermore, in steps B and C, after each mid-span steel beam segment is installed and the stay cables are symmetrically tensioned, the corresponding mid-span bridge deck segment is poured before installing the next mid-span steel beam segment; the construction sequence of the second part of the side span concrete segments corresponds to that of the mid-span bridge deck segments.

[0091] Specifically, steps B and C in this embodiment are replaced entirely with the following steps:

[0092] S1. Install one section of the mid-span steel beam 8; pour one corresponding section of the side span concrete first part 6; tension the stay cables 4 corresponding to the mid-span steel beam 8 and the side span concrete first part 6 respectively;

[0093] S2. Cast the 9th segment of the mid-span bridge deck corresponding to the 8th segment of the mid-span steel beam; cast the 7th segment of the second part of the side-span concrete corresponding to the 6th segment of the first part of the side-span concrete; and tension the stay cables 4 corresponding to the 8th segment of the mid-span steel beam and the 6th segment of the first part of the side-span concrete again.

[0094] S3. Repeat S1 and S2 until the construction of all 9 segments of the mid-span bridge deck and the second part of the 7 segments of the side span concrete is completed. Then proceed to step D and complete the construction of the hybrid beam cable-stayed bridge.

[0095] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of constructing a hybrid girder cable-stayed bridge, characterized by, It includes the following steps: A. Move the side span main beam skeleton (5) from the abutment (3) toward the bridge tower (1); connect both ends of the side span main beam skeleton (5) to the abutment (3) and the bridge tower (1) respectively; connect a balance cable (11) to the side of the bridge tower (1) away from the abutment (3); the balance cable (11) is used to balance the weight of the side span main beam skeleton (5), and the other end of the balance cable (11) is connected to another bridge tower (1); tension the stay cable (4) corresponding to the side span main beam skeleton (5). B. Install the mid-span steel beam (8) on the side of the bridge tower (1) away from the abutment (3); pour the first part (6) of the side span concrete on the side of the bridge tower (1) facing the abutment (3); install the mid-span steel beam (8) in segments along the length direction, and pour the first part (6) of the side span concrete in segments along the length direction, and match the weight of the mid-span steel beam (8) segment with the first part (6) of the side span concrete segment, and construct the mid-span steel beam (8) segment and the first part (6) of the side span concrete segment symmetrically; tension the stay cables (4) corresponding to the mid-span steel beam (8) and the first part (6) of the side span concrete segment respectively. C. Cast the mid-span bridge deck (9) and the second part of the side span concrete (7); the mid-span bridge deck (9) is cast in segments along the length direction, and the second part of the side span concrete (7) is also cast in segments along the length direction, and the weights of the mid-span bridge deck (9) segments and the second part of the side span concrete (7) segments are matched; the mid-span bridge deck (9) segments and the second part of the side span concrete (7) segments are constructed symmetrically; the stay cables (4) corresponding to the mid-span steel beam (8) and the first part of the side span concrete (6) are tensioned again.

2. The construction method for a hybrid beam cable-stayed bridge according to claim 1, characterized in that, Steps B and C can be replaced with the following steps: S1. Install one section of the mid-span steel beam (8); pour one corresponding section of the first part (6) of the side span concrete; tension the stay cables (4) corresponding to the mid-span steel beam (8) and the first part (6) of the side span concrete respectively. S2. Cast the mid-span bridge deck (9) segment corresponding to the mid-span steel beam (8) segment; cast the side span concrete second part (7) segment corresponding to the side span concrete first part (6) segment; and re-tension the stay cables (4) corresponding to the mid-span steel beam (8) and the side span concrete first part (6) respectively. S3. Repeat S1 and S2 until all the mid-span bridge deck (9) segments and the second part (7) of the side span concrete are completed.

3. A construction method for a hybrid beam cable-stayed bridge according to any one of claims 1 to 2, characterized in that, Moving the main beam frame (5) from the abutment (3) to the tower (1) specifically includes the following steps: A1. Assemble the main beam frame (5) of the side span in segments at the abutment (3); A2. Push the main beam frame (5) of the side span towards the bridge tower (1); A3. Repeat A1 and A2 until the main beam frame (5) of the side span reaches the bridge tower (1).

4. The construction method for a hybrid beam cable-stayed bridge according to claim 3, characterized in that, The following steps are included before step A: A0. Construction jacking auxiliary pier (10); the jacking auxiliary pier (10) is used to assist in supporting the side span main beam frame (5) during the jacking operation of the side span main beam frame (5).

5. A construction method for a hybrid beam cable-stayed bridge according to any one of claims 1 to 2, characterized in that, Before moving the side span main beam frame (5) in step A, a steel guide beam (12) is connected to the side span main beam frame (5).

6. A construction method for a hybrid beam cable-stayed bridge according to any one of claims 1 to 2, characterized in that, After tensioning the stay cables (4) in step A, concrete is poured at the joints of the main beam frame (5) with the abutment (3), the bridge tower (1) and the auxiliary pier (2).

7. A construction method for a hybrid beam cable-stayed bridge according to any one of claims 1 to 2, characterized in that, A bridge deck crane was used when installing the mid-span steel beam (8).

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