Prestressed concrete cable-stayed bridge side span uniform distribution type counterweight process

Abstract

The application discloses a prestressed concrete cable-stayed bridge side span uniform distribution type counterweight process, which comprises the following steps: step one, erecting a consolidation section main beam construction support to complete the construction of the consolidation section main beam and a transition pier; step two, installing front fulcrum hanging baskets on both sides of the consolidation section main beam, suspending and pouring beam section concrete on the front fulcrum hanging baskets, tensioning stay cables, completing the first beam section construction, gradually moving the hanging baskets forward, tensioning the stay cables, and sequentially completing the construction of the main beam section; step three, building an auxiliary pier, installing a continuous beam support on the top of the auxiliary pier, completing the construction of the auxiliary pier beam section on the top of the continuous beam support, and laying weight pieces on the top deck of the auxiliary pier beam section; and step four, completing the construction of a midspan closure section, adjusting the stay cable force after the closure is completed, and constructing bridge deck auxiliary works. The application adopts a uniform distribution type deck weight way on the top of the auxiliary pier, so that the weight layer is on the deck construction, the construction difficulty is greatly reduced, and the beam internal maintenance passage is smooth.

Description

Technical Field

[0001] This invention belongs to the field of bridge construction technology. More specifically, this invention relates to a uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge. Background Technology

[0002] A cable-stayed bridge, also known as a skeletal-stayed bridge, is a type of bridge where the main girder is directly anchored to the bridge towers by numerous cables. It is a structural system composed of compression-bearing towers, tension-bearing cables, and bending-resistant girder sections. In operational conditions, cable-stayed bridges experience significant negative support reactions at the auxiliary piers. Currently, there are two conventional methods to address these negative support reactions: one is to install a cable system connecting the main girder to the piers; the other is to apply counterweights. Due to the limited internal space of cable-stayed bridges and the difficulties in design and construction, the second method is generally more commonly used. Typically, to effectively address the negative support reactions at the auxiliary piers, the applied counterweights are not only very heavy but also require precise control. For example, the invention patent with publication number CN202401384U discloses a counterweight structure for a steel truss cable-stayed bridge, including upper counterweight concrete and lower counterweight concrete. However, the upper and lower counterweight concrete are usually large in volume, making them not only difficult to place during bridge construction, but also difficult to control precisely. During pouring, due to the heat of hydration of cement and the low thermal conductivity of concrete, the temperature difference between the inside and outside is easily too large. Large-volume concrete structures are prone to early cracks, thereby reducing or even destroying the load-bearing capacity of the structure and affecting the stability and firmness of the concrete. In addition, the above-mentioned counterweight concrete is placed inside the steel box, which presents construction difficulties and affects the maintenance access. Summary of the Invention

[0003] One objective of this invention is to provide a uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge, in which the counterweight layer is constructed on the bridge deck, greatly reducing the construction difficulty and enabling precise control of the counterweight.

[0004] To achieve these and other advantages according to the invention, according to one aspect of the invention, the invention provides a process for uniformly distributed counterweights in the side spans of a prestressed concrete cable-stayed bridge, comprising the following steps:

[0005] Step 1: Erect the construction support for the main beam of the consolidation section to complete the construction of the main beam of the consolidation section and the transition pier;

[0006] Step 2: Install the front support hanging basket on both sides of the main beam in the consolidation section, pour the beam segment concrete on the front support hanging basket, tension the stay cables, and complete the construction of the first beam segment. The hanging basket is gradually moved forward, and the stay cables are tensioned to complete the construction of the main beam segments in sequence.

[0007] Step 3: Construct auxiliary piers, install continuous beam supports on top of the auxiliary piers, complete the construction of the auxiliary pier beam segment on top of the continuous beam supports, and lay counterweights on the bridge deck on top of the auxiliary pier beam segment.

[0008] Step 4: Complete the construction of the mid-span closure section. After the closure is completed, adjust the cable tension of the stay cables and construct the bridge deck ancillary works.

[0009] Preferably, the top of the auxiliary pier beam section is symmetrically provided with counterweight grooves on both sides, and the counterweights are symmetrically placed into the counterweight grooves on both sides. The counterweights include a central counterweight block, a secondary counterweight block, and a side counterweight block that are sequentially located away from the auxiliary pier. The top of the central counterweight block is provided with a first slot on the side near the secondary counterweight block. The side counterweight block is provided with a first protruding ridge extending vertically outward on the side near the secondary counterweight block. The secondary counterweights include multiple secondary counterweight blocks. The top of each secondary counterweight block is provided with a second slot on the side near the side counterweight block. Each secondary counterweight block is provided with a second protruding ridge extending vertically outward on the side near the central counterweight block. The central counterweight block, multiple secondary counterweight blocks, and side counterweight blocks of each counterweight are sequentially overlapped and matched to be accommodated in any counterweight groove.

[0010] Preferably, the multiple secondary weight blocks in each secondary weight component are respectively a first weight block, a second weight block, and a third weight block that are sequentially moved away from the central weight block, and the first weight block, the second weight block, and the third weight block are provided with different numbers of notches.

[0011] Preferably, the weight of the second ballast block is 60% to 80% of the weight of the third ballast block, and the weight of the first ballast block is 70% to 90% of the weight of the second ballast block.

[0012] Preferably, anti-slip felt is provided between adjacent medium pressure blocks, secondary pressure blocks and side pressure blocks.

[0013] Preferably, the first and second protruding edges have the same shape and size, the first and second card slots have the same shape and size, and the first and second protruding edges match the first and second card slots.

[0014] Preferably, the heights of the multiple intermediate pressure blocks, secondary pressure blocks, and side pressure blocks are all consistent with the height of the counterweight groove.

[0015] Preferably, the end of the intermediate counterweight near the auxiliary pier and the end of the side counterweight away from the auxiliary pier are both matched with the sidewall of the counterweight groove.

[0016] Preferably, the counterweight is made of C30 concrete or iron sand concrete.

[0017] The present invention has at least the following beneficial effects: the uniformly distributed counterweight process of the prestressed concrete cable-stayed bridge side spans described in the present invention adopts a uniformly distributed bridge deck counterweight method on the top of the auxiliary piers to prevent concentrated counterweight on the top of the piers. The counterweight layer and the leveling layer are constructed simultaneously, which reduces the construction difficulty and facilitates smooth maintenance access within the beam.

[0018] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a cable-stayed bridge according to one technical solution of the present invention;

[0020] Figure 2 This is a structural schematic diagram of the auxiliary pier and the auxiliary pier beam segment in one technical solution of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the counterweight in one technical solution of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the first counterweight block in one technical solution of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of the second counterweight block in one technical solution of the present invention;

[0024] Figure 6 This is a schematic diagram of the structure of the third counterweight block in one technical solution of the present invention. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can implement it based on the description.

[0026] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0027] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are conventional methods, and the reagents and materials mentioned are commercially available. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "setting" should be interpreted broadly. For example, they can refer to fixed connection or setting, detachable connection or setting, or integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description. They 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 invention.

[0028] like Figures 1-6 As shown, this invention provides a process for uniformly distributed counterweights in the side spans of prestressed concrete cable-stayed bridges, including the following steps:

[0029] Step 1: Erect the construction support for the main beam of the consolidation section, and complete the construction of the main beam of the consolidation section and the transition pier 200.

[0030] Step 2: Install the front support hanging basket on both sides of the main beam in the consolidation section, pour the beam segment concrete on the front support hanging basket, tension the stay cables, and complete the construction of the first beam segment. The hanging basket is gradually moved forward, and the stay cables are tensioned to complete the construction of the main beam segments in sequence.

[0031] Step 3: Construct auxiliary pier 100, install continuous beam support 101 on top of auxiliary pier 100, complete the construction of auxiliary pier beam segment 102 on top of continuous beam support 101, and lay counterweights on the bridge deck on top of auxiliary pier beam segment 102.

[0032] Step 4: Complete the construction of the mid-span closure section. After the closure is completed, adjust the cable tension of the stay cables and construct the bridge deck ancillary works.

[0033] In this technical solution, the prestressed concrete cable-stayed bridge side span uniformly distributed counterweight process includes the following stages: the first to second stages involve completing the tower construction, erecting the construction support for the main beam of the fixed section, setting up the formwork and tying the reinforcing bars, pouring concrete, and after the concrete strength reaches 90% of the design strength, tensioning the longitudinal and transverse prestressed steel strands of the main beam, dismantling the construction support, completing the construction of this beam segment, and completing the construction of the transition pier; the third stage involves installing the front support hanging basket on both sides of the main beam of the fixed section, installing the stay cables, tensioning the stay cables for the first time, tying the reinforcing bars, pouring the beam segment concrete, tensioning the prestressed strands of the main beam, tensioning the prestressed strands of the transverse diaphragm, tensioning the stay cables for the second time, cutting the small stay cables, and completing the construction of this beam segment; In the fourth stage, the formwork is moved forward 7.1 meters, the stay cables are installed and tensioned for the first time, the reinforcing bars are tied, the beam segment concrete is poured, the prestressing tendons of the main beam are tensioned, the prestressing tendons of the transverse diaphragm are tensioned, the stay cables are tensioned for the second time, and the small stay cables are cut, completing the construction of this beam segment. From the fifth to the twenty-fifth stage, the main beam segments are constructed sequentially, with auxiliary piers constructed simultaneously, and the continuous beam supports on the pier tops are installed. From the twenty-sixth to the thirty-first stage, the side spans are closed, and the auxiliary pier construction is completed simultaneously, with the counterweight layer installed on the bridge deck. In the thirty-second stage, the formwork is used to construct the mid-span closure segment. In the thirty-third stage, after closure, the stay cable tension is adjusted, expansion joints are installed, the upper bridge deck is paved, guardrails and stay cable dampers are installed, a bridge test is conducted, and final acceptance is performed. In addition, each beam segment is equipped with an inspection passage and multiple sets of parallel reinforcing bars. The inspection passage facilitates internal maintenance of the beam, and the multiple sets of reinforcing bars include transverse and longitudinal reinforcing bars to improve structural strength.

[0034] In other technical solutions, counterweight grooves 103 are symmetrically provided on both sides of the top of the auxiliary pier beam section. The counterweights are symmetrically placed into the counterweight grooves on both sides. The counterweights include a central counterweight block 110, a secondary counterweight, and a side counterweight block 112, which are sequentially located away from the auxiliary pier 100. The top of the central counterweight block 110 is provided with a first slot 113 on the side near the secondary counterweight. The side counterweight block 112 is provided with a first protruding ridge 114 extending vertically outward on the side near the secondary counterweight. The secondary counterweight includes multiple secondary counterweight blocks. The top of each secondary counterweight block is provided with a second slot 115 on the side near the side counterweight block 112. The side of each secondary counterweight block is provided with a second protruding ridge 116 extending vertically outward on the side near the central counterweight block 110. The central counterweight block 110, multiple secondary counterweight blocks, and side counterweight blocks 112 of each counterweight are sequentially overlapped and matched and accommodated in any counterweight groove 103.

[0035] In this technical solution, the counterweight components in each counterweight groove 103 include, from the center outwards, a central counterweight block 110, multiple secondary counterweight blocks, and a side counterweight block 112. By adjusting the weight variation pattern of the multiple counterweight blocks, the purpose of precise control of the counterweight is achieved. The counterweight components in the counterweight groove located to the left of the auxiliary pier 100 have a first protruding ridge 114 extending vertically to the right on the upper right side of the side counterweight block 112. Multiple secondary counterweight blocks have second slots 115 matching the first protruding ridge 114 on the upper left side, and multiple secondary counterweight blocks have second protruding ridges 116 identical to the first protruding ridge 114 on the upper right side. The central counterweight block 110 has a first slot 113 extending vertically to the left on the upper left side. The multiple counterweight blocks overlap and match each other within the counterweight groove, improving the stability of the structure. The top of the auxiliary pier 100 adopts a uniform bridge deck ballast method to prevent concentrated ballast on the pier top. Within a range of about 130m from the top of the auxiliary pier 100, the ballast layer and the paving and leveling layer on the beam top are constructed simultaneously. The ballast layer is constructed on the bridge deck, which reduces the construction difficulty and facilitates smooth maintenance access inside the beam.

[0036] In other technical solutions, the multiple secondary counterweight blocks in each secondary counterweight component are respectively a first counterweight block 120, a second counterweight block 121, and a third counterweight block 122, which are sequentially located away from the central counterweight block 110. The first counterweight block 120, the second counterweight block 121, and the third counterweight block 122 each have a different number of notches 123. In this technical solution, the multiple secondary counterweight blocks are divided into three types. By adjusting their arrangement order, different counterweight requirements can be met, improving the adaptability of the structure.

[0037] In other technical solutions, the weight of the second counterweight 121 is 60% to 80% of the weight of the third counterweight 122, and the weight of the first counterweight 120 is 70% to 90% of the weight of the second counterweight 121. In this technical solution, the weights of the first counterweight 120, the second counterweight 121, and the third counterweight 122 increase in a regular pattern to meet the requirements of precise counterweighting.

[0038] In other technical solutions, anti-slip felt is provided between adjacent intermediate pressure blocks 110, secondary pressure blocks, and side pressure blocks 112. In this technical solution, the anti-slip felt is provided to improve structural stability.

[0039] In other technical solutions, the first protruding ridge 114 and the second protruding ridge 116 have the same shape and size, and the first slot 113 and the second slot 115 have the same shape and size, and the first protruding ridge 114 and the second protruding ridge 116 match the first slot 113 and the second slot 115. In this technical solution, the sizes and shapes of the two types of protruding ridges and the two types of slots are matched, so that after multiple counterweight blocks are stacked in sequence, they can be matched and accommodated in the counterweight groove, avoiding structural gaps that could lead to uneven stress and improving structural stability.

[0040] In other technical solutions, the heights of multiple intermediate counterweight blocks 110, secondary counterweight blocks, and edge counterweight blocks 112 are all consistent with the height of the counterweight groove 103. In this technical solution, the height of the counterweight components is consistent with the height of the counterweight groove, which facilitates the construction of the leveling layer.

[0041] In other technical solutions, the end of the central counterweight 110 near the auxiliary pier 100 and the end of the side counterweight 112 away from the auxiliary pier 100 are both matched with the side wall of the counterweight groove 103.

[0042] In other technical solutions, the counterweight is made of C30 concrete or iron sand concrete. In this technical solution, the counterweight can be made of different materials to meet different counterweight requirements.

[0043] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A prestressed concrete cable-stayed bridge with uniformly distributed counterweights in the side spans, characterized in that, Includes the following steps: Step 1: Erect the construction support for the main beam of the consolidation section to complete the construction of the main beam of the consolidation section and the transition pier; Step 2: Install the front support hanging basket on both sides of the main beam in the consolidation section, pour the beam segment concrete on the front support hanging basket, tension the stay cables, and complete the construction of the first beam segment. The hanging basket is gradually moved forward, and the stay cables are tensioned to complete the construction of the main beam segments in sequence. Step 3: Construct auxiliary piers. Install continuous beam supports on the top of the auxiliary piers. Complete the construction of the auxiliary pier beam segment on the top of the continuous beam supports. Lay counterweights on the bridge deck at the top of the auxiliary pier beam segment. Counterweight slots are symmetrically opened on both sides of the top of the auxiliary pier beam segment. The counterweights are symmetrically placed into the counterweight slots on both sides. The counterweights include a central counterweight block, a secondary counterweight block, and a side counterweight block, which are sequentially located away from the auxiliary pier. The top of the central counterweight block is provided with a first slot on the side near the secondary counterweight block. The side counterweight block is provided with a first protruding ridge extending vertically outward on the side near the secondary counterweight block. The secondary counterweights include multiple secondary counterweight blocks. The top of each secondary counterweight block is provided with a second slot on the side near the side counterweight block. The side of each secondary counterweight block is provided with a second protruding ridge extending vertically outward on the side near the central counterweight block. The central counterweight block, multiple secondary counterweight blocks, and side counterweight blocks of each counterweight are sequentially overlapped and matched to be accommodated in any counterweight slot. Step 4: Complete the construction of the mid-span closure section. After the closure is completed, adjust the cable tension of the stay cables and construct the bridge deck ancillary works.

2. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, The multiple secondary weight blocks in each secondary weight component are a first weight block, a second weight block, and a third weight block that are sequentially located away from the central weight block. The first weight block, the second weight block, and the third weight block each have a different number of notches.

3. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 2, characterized in that, The weight of the second ballast block is 60% to 80% of the weight of the third ballast block, and the weight of the first ballast block is 70% to 90% of the weight of the second ballast block.

4. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, Anti-slip felt is installed between adjacent medium pressure blocks, secondary pressure blocks and edge pressure blocks.

5. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, The first and second protruding edges have the same shape and size, the first and second card slots have the same shape and size, and the first and second protruding edges match the first and second card slots.

6. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, The heights of multiple medium-pressure blocks, secondary-pressure blocks, and side-pressure blocks are all consistent with the height of the counterweight groove.

7. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, The ends of the central counterweight near the auxiliary pier and the ends of the side counterweights away from the auxiliary pier are both matched with the sidewalls of the counterweight groove.

8. The uniformly distributed counterweight process for the side spans of a prestressed concrete cable-stayed bridge as described in claim 1, characterized in that, The counterweight is made of C30 concrete.

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