CN115573238A - Ballast area structure of steel truss girder cable-stayed bridge and construction method thereof - Google Patents

Abstract

The invention relates to a structure of a ballast area of a steel truss girder cable-stayed bridge and a construction method thereof. A ballast zone structure of a steel truss girder cable-stayed bridge, comprising a base plate and two side plates, the base plate and the side plates are all arranged between two adjacent deck beams of the steel truss girder, the base plate, The two side plates, the steel bridge decks corresponding to the two adjacent deck beams and the steel truss girders can enclose a closed structure, and the closed structure is filled with ballast. It simplifies the connection structure between the ballast area and the steel girder, the steel utilization rate is high, and the steel consumption is smaller; the construction space is larger, the construction steps are fewer, the construction is simpler, and the installation efficiency is higher; the steel bridge in the closed structure Neither the deck nor the deck system below require post-maintenance.

Description

Ballast zone structure and construction method of a steel truss girder cable-stayed bridge

technical field

The invention relates to the technical field of bridge weight of cable-stayed bridges, in particular to a structure of a ballast area of a steel truss girder cable-stayed bridge and a construction method thereof.

Background technique

The support reaction force problem of multi-line long-span steel truss girder cable-stayed bridges is very prominent. Adding a ballast area to the side span is the most common and effective method for steel truss cable-stayed bridges to eliminate support reaction forces and provide pressure reserves under operating conditions. Methods.

The structure of the existing steel truss girder cable-stayed bridge ballast area mainly includes two types of bridge deck ballast and bridge deck ballast boxes. Heavy box, pouring ballast concrete in the ballast box, as shown in Figure 1, below the bridge deck 2 is the bridge deck system composed of longitudinal and horizontal beams, and the ballast box 3 is set on the bridge deck system, which needs to be placed between the longitudinal beams of the bridge deck system or on the bridge deck A member supporting the ballast box 3 is arranged between the beams 1. For example, several small longitudinal beams 5 are bolted on the bridge deck beam 1, and the ballast box 3 is supported on the small longitudinal beams 5. All the weight is borne by the small longitudinal beams 5. This structure has the following problems:

(1) The installation of the ballast box 3 can only be carried out after the construction of the small longitudinal beam 5 is completed. The construction space is limited, and the difficulty of constructing the ballast box 3 is relatively large and the process is relatively complicated.

(2) Multiple ballast boxes 3 are arranged along the transverse bridge direction, and a single ballast box 3 has a small capacity and low ballast efficiency; after the ballast box 3 is installed, the space under the bridge deck system is limited, which brings inconvenience to the later maintenance of this part; And in order to meet the subsequent maintenance of the bridge deck 2, it is necessary to reserve a certain space above the ballast box 3, such as a space with a height of 1-1.5m, so that the vertical range of the bridge where the ballast box 3 can be arranged is small; in order to increase the ballast weight, it is necessary to increase the height The bridge deck is connected to the beam 1 or the bulk density is increased. Because the installation space of the ballast box 3 of the steel truss girder is extremely limited, in order to save the amount of materials in the ballast area and reduce the volume of the ballast area, the material of the ballast area of the existing steel truss girder cable-stayed bridge is mainly used There are two types of iron sand concrete and barite concrete. In terms of ballast materials, the greater the bulk density of heavy concrete 4, the more difficult it is to pump. Especially in the case of high bridge heights, special pumping processes are usually required, and Compared with ordinary concrete, heavy concrete 4 is more expensive.

Contents of the invention

The object of the present invention is: for the structure of the ballast area of the steel truss girder cable-stayed bridge of the prior art, some small longitudinal girders are bolted on the deck system crossbeams below the bridge deck system, and several ballast boxes are supported on the small longitudinal girders. method, there are problems such as complex connection, large steel consumption, low steel utilization rate, and difficult and complicated construction and maintenance. A kind of ballast zone structure and construction method of steel truss girder cable-stayed bridge is provided.

In order to achieve the above object, the technical scheme adopted in the present invention is:

A ballast area structure of a steel truss girder cable-stayed bridge, comprising a base plate and two side plates, the base plate and the side plates are all arranged between two adjacent deck beams of the steel truss girder, the base plate, The two side plates, the steel bridge decks corresponding to the two adjacent deck beams and the steel truss girders can enclose a closed structure, and the closed structure is filled with ballast bodies.

The ballast body can be poured with concrete, mortar and other ballast materials in the prior art; the bulk density and closed structure of the ballast body are designed according to actual construction conditions, and the bottom plate and side plates are designed according to actual construction conditions.

The structure of the ballast area of the steel truss girder cable-stayed bridge described in this scheme is surrounded by the bottom plate, the two side plates, the corresponding two adjacent bridge deck beams and the steel bridge deck of the steel truss girder The closed structure enables the space between two adjacent bridge deck beams to be filled with ballast materials, so that the structure of the ballast area is combined with the steel truss girder to realize the ballast function.

In the structure of the ballast area of the steel truss girder cable-stayed bridge, the bottom plate and the two side plates are supported by beams on the bridge deck, so there is no need to separately set up small longitudinal beams for support; and the closed structure is a large and closed ballast box, The closed structure is formed by the bridge deck system and deck of steel truss girders, which simplifies the connection structure between the ballast area and the steel girders; and the bridge deck system and deck deck of steel truss girders are not only the bridge structure, but also the pressure of the ballast body. A part of the heavy box has a high steel utilization rate; and the closed structure has a larger total volume than the ballast box between two adjacent bridge deck beams in the prior art, which can reduce the bulk density of the ballast material, thereby reducing the cost. There is no need to increase the ballast by increasing the height of the bridge deck beams or larger bridge deck beams as in the prior art; the above-mentioned reasons make the steel consumption of the ballast zone structure smaller. And because there is no need to set small longitudinal beams, only the bottom plate and side plates need to be installed between two adjacent deck beams, the construction space is larger, the construction steps are fewer, and the construction is simpler; both the bottom plate and the side plates can be installed after installation. The two adjacent bridge decks are installed in time after the beams are tied, which can improve the installation efficiency. After filling the closed structure with the ballast material, the ballast material can form a direct support for the steel bridge deck, which can effectively improve the fatigue characteristics of the steel bridge deck, so that the steel bridge deck at the closed structure and the deck system below do not need post-processing maintenance, the entire structure of the ballast zone is also maintenance-free.

Preferably, the lower part of the ballast body is an ordinary concrete layer, and the upper part is a self-compacting cement mortar layer.

This solution adopts a closed structure, compared with the total volume of all ballast boxes between two adjacent bridge deck beams in the prior art, which enables the use of the specific density of concrete under the condition of ensuring the same ballast Smaller ordinary concrete and self-compacting cement mortar are used to realize the pressure. The ordinary concrete layer in the lower part of the closed structure has a strong bearing capacity, and the self-compacting cement mortar layer is conducive to filling the upper part of the closed structure, while ensuring safety and compactness. And compared with heavy concrete, filling the internal space of the closed structure with ordinary concrete layer and self-compacting cement mortar layer, the construction is simpler, and the cost of the material itself is also lower, which can save construction cost.

Preferably, the height of the top surface of the ordinary concrete layer is not higher than the bottom of the U-rib of the steel bridge deck.

U-ribs are U-shaped stiffeners arranged along the longitudinal bridge direction on the bottom surface of steel bridge decks. The actual height of the ordinary concrete layer is determined according to the specific weight, but the height of the top surface of the ordinary concrete layer should not be higher than the bottom of the U-rib of the steel bridge deck, so that the U-rib of the bridge deck can be better filled with self-compacting cement mortar and other corners to improve the filling effect in the closed structure.

Preferably, the side plate is provided with a manhole, the top of the manhole is higher than the top surface of the ordinary concrete layer, and the ordinary concrete layer is poured through the manhole.

Construction personnel can enter the manhole to pour ordinary concrete, which is convenient for pouring ordinary concrete layers, and can improve the quality of pouring, and there is no need to open redundant pouring ports on the side plates for pouring ordinary concrete layers, which can improve the integrity of the closed structure.

Preferably, several first stiffeners are provided above the bottom plate, and several second stiffeners are provided on the inner side of the side plate.

The strength and rigidity of the bottom plate can be enhanced through the first stiffener, and the strength and rigidity of the side plate can be enhanced through the second stiffener. The first stiffener is arranged on the top surface of the bottom plate, so that the bottom plate is more closely connected with the weight material in the closed structure; the second stiffener is arranged on the inner side of the side plate, so that the side plate can be connected with the pressure material in the closed structure Tighter connection of heavy materials; improves integrity and stability of ballast zone construction.

Preferably, several first stiffeners are arranged along the longitudinal bridge direction, and the first stiffeners are connected to the corresponding joint plates of the bridge deck beams by first high-strength bolts; The sides are respectively connected to the web stiffeners of the two bridge deck beams through second high-strength bolts.

The joint plate is vertically arranged at the corner of the web of the bridge deck beam and the lower wing plate, and the first stiffener is arranged on the top surface of the bottom plate along the longitudinal direction of the bridge and corresponding to the position of the joint plate, so as to ensure the support of the bottom plate. At the same time of sufficient reinforcement, the bottom plate and the bridge deck beam can be connected more stably through the first high-strength bolts. The inner side of the side panel refers to the side of the side panel facing the inside of the closed structure. The web of the bridge deck beam has vertically arranged web stiffeners, and the connection between the side plate and the bridge deck beam is more stable through the second high-strength bolts. Through the first stiffener, the first high-strength bolt and the second high-strength bolt, the installation quality of the bottom plate and side plate can be improved, and the quality of the closed structure can be improved, so that the ballast area of the steel truss cable-stayed bridge described in this scheme The structure can be better applied to bridges formed by loosely joining members.

Preferably, the second stiffener is arranged vertically, because the vertical height of the side plate is higher than that of the existing ballast box, by setting the second vertical stiffener, the side plate can be better strengthened .

Preferably, the thickness of the bottom plate is 10-16mm, and the thickness of the side plate is greater than or equal to 10mm. After being strengthened by the first stiffener and the second stiffener, it is possible to use a thinner bottom plate and side plate, that is, a bottom plate with a thickness of 10-16mm can be used, and a side plate with a thickness greater than or equal to 10mm can be used, In turn, the steel consumption can be reduced, the cost can be saved, and the hoisting of the side plate and the bottom plate is more convenient.

A construction method of a ballast zone structure of a steel truss girder cable-stayed bridge, comprising the following steps:

S1. The bottom slab, two side slabs, two bridge deck beams and steel bridge decks are constructed in each ballast area to form a closed structure;

S2. After the main girder of the cable-stayed bridge is closed, firstly pour a layer of ordinary concrete into the closed structure, and then pour a layer of self-compacting cement mortar.

Compared with the construction of the existing ballast box, the ballast area structure of the steel truss girder cable-stayed bridge in the present invention can be constructed safely and quickly through the above method, and its construction is simpler.

Preferably, in step S2, the ordinary concrete layer is divided into two layers of construction, the first layer is poured on the bottom plate first, and the second layer is poured on the first layer after the strength of the first layer reaches the standard. layer.

Through the above construction method, the bearing capacity of the first layer of ordinary concrete is effectively utilized, so that the thinner base plate and the first stiffener only need to be able to bear the weight of the first layer of ordinary concrete. The steel-concrete structure formed by the bottom plate can effectively bear the total weight of the second layer of ordinary concrete and self-compacting cement mortar layer.

Preferably, in the step S2, the ordinary concrete layer is poured through a manhole, and the manhole is located on one of the side plates;

During the pouring process of the second layer, when the height of the poured ordinary concrete is higher than the bottom of the manhole, the pouring of ordinary concrete is carried out by gradually sealing up the manhole until the second layer is poured. Complete, then completely seal off said manhole;

After the strength of the second layer reaches the standard, a pouring hole is opened in the steel bridge deck, and a self-compacting cement mortar layer is poured through the pouring hole until the closed structure is filled, and then the pouring hole is closed.

When the height of the poured ordinary concrete is higher than the bottom of the manhole, the manhole is gradually blocked as the pouring height increases until the second layer of pouring is completed. Pouring the ordinary concrete layer through the manhole on the side plate can better ensure the quality of pouring when the ordinary concrete layer is poured in layers, and the manhole will be closed after the second layer of the ordinary concrete layer is poured, and the entire closed structure is completely closed. If it is closed and cannot be poured, a pouring hole is opened above the steel bridge deck corresponding to the U rib and the U rib or between the U rib and the bridge deck longitudinal beam. The pouring hole is preferably 4-6cm, and pouring through the pouring hole The self-compacting cement mortar layer can fill the closed structure more conveniently, quickly and with high quality, avoiding that the U-ribs and bridge deck longitudinal beams cannot be completely filled. This construction method of manholes combined with small pouring holes can minimize the impact on A large number of larger pouring gates are opened in the structure of the ballast area to ensure the integrity of the structure of the ballast area and improve the quality of the structure of the ballast area.

Preferably, in step S1, when the steel truss girder is constructed to the girder section in the ballast area, after two adjacent bridge deck beams are hoisted, the corresponding adjacent two deck beams The bottom plate and the side plates are hoisted between to form the closed structure.

When the construction site of the beam section in the ballast area is limited, or large-scale lifting equipment cannot be transported to the construction site of the beam section in the ballast area, it is impossible to assemble the beam section in the ballast area on the ground before overall hoisting. The closed structure is formed by hoisting the bottom plate and the side plate in time after hoisting the two adjacent bridge deck beams, which can avoid the restriction of the construction site, do not need to use large lifting equipment, and the construction steps are simpler. And this assembling method will not affect the quality of the closed structure.

Preferably, in step S1, when installing the bottom plate and the side plate between the corresponding two adjacent bridge deck beams, the first high-strength bolt and the second high-strength bolt are initially screwed, and the construction of the beam section in the ballast area is completed. Finally, tighten the first high-strength bolt and the second high-strength bolt.

Wherein, the first high-strength bolt is used to connect the first stiffener and the corresponding joint plate, the first stiffener is arranged on the bottom plate along the longitudinal bridge direction, and the joint plate is vertically arranged on the bridge deck beam. At the corner of the web and the lower wing; the second high-strength bolts are used to connect the longitudinal bridges of the side plates to the two sides respectively corresponding to the web stiffeners of the two bridge deck beams, and the web stiffeners are vertical Set on the web of the beam on the bridge deck.

Through the above construction method, it is convenient to adjust the connection between the bottom plate and the side plate.

In summary, owing to adopting above-mentioned technical scheme, the beneficial effect of the present invention is:

1. The structure of the ballast area of the steel truss girder cable-stayed bridge of the present invention, through the bottom plate, the two side plates, the corresponding two adjacent deck beams and the steel bridge deck of the steel truss girder Enclose a closed structure, so that the space between two adjacent deck beams can be filled with ballast materials, so that the structure of the ballast area is combined with the steel truss girder, and the filling volume of the ballast material in the closed structure Larger, can better realize the lifting of the weight of the ballast; there is no need to set up small longitudinal girder support separately, and the closed structure is formed by means of the bridge deck system and deck of the steel truss girder, which simplifies the connection between the ballast area and the steel girder The connection structure has a high steel utilization rate, which makes the steel consumption smaller; and the total capacity of the closed structure is large, and there is no need to increase the pressure by increasing the height of the bridge deck beam or a larger bridge deck beam in the prior art, thereby reducing The amount of steel used. And because there is no need to set small longitudinal beams, only the bottom plate and side plates need to be installed between two adjacent deck beams, the construction space is larger, the construction steps are fewer, and the construction is simpler; both the bottom plate and the side plates can be installed after installation. The two adjacent bridge decks are installed in time after the beams are tied, which can improve the installation efficiency. After filling the closed structure with the ballast material, the ballast material can form a direct support for the steel bridge deck, which can effectively improve the fatigue characteristics of the steel bridge deck, so that the steel bridge deck at the closed structure and the deck system below do not need post-processing maintenance, the entire structure of the ballast zone is also maintenance-free.

2. The ordinary concrete layer in the lower part of the closed structure has a strong bearing capacity, and the self-compacting cement mortar layer is conducive to filling the upper part of the closed structure, while ensuring safety and compactness, and compared with heavy concrete, through the ordinary concrete layer and self-concrete The dense cement mortar layer fills the internal space of the closed structure, and its construction is simpler, and the cost of the material itself is also lower, thereby saving construction costs.

3. The construction method of the ballast area structure of the steel truss cable-stayed bridge of the present invention, compared with the construction of the existing ballast box, can safely and quickly construct the pressure of the steel truss cable-stayed bridge in the present invention. Heavy area structure, its construction is simpler.

4. The construction method of manholes combined with small pouring holes can minimize the opening of a large number of large pouring openings for the structure of the ballast area, ensure the integrity of the structure of the ballast area, and improve the quality of the structure of the ballast area. The above-mentioned steel bridge deck corresponds to opening pouring holes between its U ribs and U ribs or between U ribs and bridge deck longitudinal girders, which can fill the upper part of the closed structure with self-compacting cement mortar more conveniently, quickly and with high quality. U ribs and other corners, so that the closed structure is filled.

Description of drawings

Fig. 1 is the structural representation of existing steel truss girder cable-stayed bridge ballast area structure;

Icons in Fig. 1: 1-bridge beam; 2-bridge deck; 3-ballast box; 4-heavy concrete; 5-small longitudinal beam.

Fig. 2 is the cross-sectional structure schematic diagram of the ballast zone structure of steel truss girder cable-stayed bridge described in embodiment 1;

Fig. 3 is a schematic cross-sectional view at the A-A place in Fig. 2;

Fig. 4 is a schematic cross-sectional view at B-B in Fig. 2;

FIG. 5 is a schematic plan view of the structure of the ballast zone of the steel truss girder cable-stayed bridge in Embodiment 1. FIG.

Icons in Figure 2-5: 1- bridge deck beam; 2- steel bridge deck; 21- U rib; 22- bridge deck longitudinal beam; 3- bottom plate; 4- first stiffener; 5- side plate; 6- Ordinary concrete layer; 61-first layer; 62-second layer; 7-self-compacting cement mortar layer; 8-first high-strength bolt; 10-second high-strength bolt; 11-joint plate; 12-manhole; 13- Second stiffener.

detailed description

Below in conjunction with accompanying drawing, the present invention is described in detail.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Example 1

This embodiment provides a ballast area structure of a steel truss girder cable-stayed bridge, referring to Fig. Between two bridge deck beams 1, the bottom plate 3, the two side plates 5, and the steel bridge decks 2 corresponding to the adjacent two deck beams 1 and the steel truss girders can form a The closed structure is filled with ballast body.

The ballast body can be poured with concrete, mortar and other ballast materials; the bulk density of the ballast body is determined according to the required support reaction force reserve, and the bottom plate 3 and side plate 5 are designed according to the ballast weight.

The structure of the ballast area of the steel truss girder cable-stayed bridge described in this program is a steel bridge through the bottom plate 3, the two side plates 5, and the corresponding adjacent two deck beams 1 and the steel truss girders. The panels 2 form a closed structure, so that the space between two adjacent deck beams 1 can be filled with ballast materials, so that the structure of the ballast area is combined with the steel truss girder to realize the ballast function.

In this embodiment, by adopting a closed structure, the total volume of all the ballast boxes between two adjacent deck beams 1 is larger than that of the prior art, so that it can be used while ensuring the same ballast. Ordinary concrete and self-compacting cement mortar, which have a smaller bulk density than specific gravity concrete, are used to achieve compaction. Therefore, a better structure can be adopted, so that the lower part of the ballast body is an ordinary concrete layer 6, and the upper part is a self-compacting cement mortar layer 7. The ordinary concrete layer 6 in the lower part of the closed structure has a strong bearing capacity, and the self-compacting cement mortar layer 7 has It is conducive to filling the upper part of the closed structure, while ensuring safety and compactness. Compared with heavy concrete, the internal space of the closed structure is filled with the ordinary concrete layer 6 and the self-compacting cement mortar layer 7. The construction is simpler, and the material itself The cost is also lower, which can save construction costs. In addition, the actual height of the ordinary concrete layer 6 is determined according to the specific weight, but the height of the top surface of the ordinary concrete layer 6 should not be higher than the bottom of the U rib 21 of the steel bridge deck 2, so that the self-compacting cement mortar can better Fill the U-rib 21 and other corners of the bridge deck to improve the filling effect in the closed structure.

In this embodiment, the bottom plate 3 and the side plate 5 are provided with a stiffening structure, and the stiffening structure is used to strengthen the bottom plate 3 and the side plate 5, so that the ordinary concrete layer 6 and the natural concrete layer 6 can be supported by the bottom plate 3 and the side plate 5. The overall pressure of the dense cement mortar layer 7.

As shown in Figures 2, 3 and 5, a vertical joint plate 11 is provided at the corners of the web and the lower wing plate of the bridge deck beam 1 along the longitudinal direction of the bridge, and the stiffening structure of the bottom plate 3 is a number of corresponding The first stiffener 4 provided on the joint plate 11 is arranged along the longitudinal bridge direction, and the first stiffener 4 is connected to the corresponding joint plate 11 by first high-strength bolts 8 . Along the longitudinal direction of the bridge and corresponding to the position of the joint plate 11, the first stiffener 4 is provided on the top surface of the bottom plate 3, which can make the bottom plate 3 and the bridge beam 1 more stable while ensuring sufficient reinforcement of the bottom plate 3 Connection. Moreover, the first stiffener 4 is arranged on the top surface of the bottom plate 3, so that the connection between the bottom plate 3 and the ordinary concrete layer 6 is tighter, and the integrity and stability of the structure of the ballast area are improved.

The inner side of the side plate 5 refers to the side of the side plate 5 facing the inside of the closed structure. As shown in Figure 4, the web of the bridge deck beam 1 has a vertically arranged web stiffener, and the longitudinal bridge of the side plate 5 corresponds to the two sides of the bridge deck beam 1 respectively. The web stiffener is connected by the second high-strength bolt 10, so that the connection between the side plate 5 and the bridge deck beam 1 is more stable. And the stiffening structure of the side plate 5 is a plurality of second stiffening ribs 13, the second stiffening ribs 13 are vertically arranged on the inner side of the side plate 5, because the vertical height of the side plate 5 is higher than that of the existing ballast box The height is higher, and the side plate 5 can be better reinforced by setting the vertical second stiffener 13 . And the second stiffener 13 is arranged on the inner side of the side plate 5, so that the side plate 5 can be connected more closely with the ordinary concrete layer 6 and the self-compacting cement mortar layer 7, and the integrity and stability of the structure of the ballast area can be improved. .

After being strengthened by the above-mentioned first stiffener 4 and second stiffener 13, it is possible to adopt a thinner base plate 3 and side plate 5, that is, a base plate 3 with a thickness of 10-16mm can be used, and a thickness greater than or equal to The side plate 5 with a thickness of 10mm can further reduce the amount of steel used, save costs, and is more convenient for the hoisting of the side plate 5 and the bottom plate 3 .

And the side plate 5 is provided with a manhole 12, the top of the manhole 12 is higher than the top surface of the ordinary concrete layer 6, in this embodiment, only one side plate 5 of each closed structure is provided with a manhole 12 , through the manhole 12 to pour the ordinary concrete layer 6, construction personnel can enter the manhole 12 to pour ordinary concrete, which is convenient for pouring the ordinary concrete layer 6, and can improve the quality of pouring, and there is no need to separately set up redundant concrete on the side plate 5 The pouring port is used for pouring the ordinary concrete layer 6, which can improve the integrity of the closed structure.

The structure of the ballast area of the steel truss girder cable-stayed bridge described in this embodiment has a simple structure and is easy to install. The structure of the ballast area makes better use of the main structure of the steel truss girder. It only needs to add the bottom plate 3 and the side plate 5 to connect the bridge deck beam 1, and cooperate with the steel bridge deck 2 to form an overall closed structure as the ballast area, which simplifies the pressure area. The connection structure between the heavy area and the steel truss beam is connected by the first high-strength bolt 8 and the second high-strength bolt 10, which can be installed in blocks and convenient for construction. And its structural stress is clear, without changing the stress system and mechanical performance of the steel truss girder, and the cable force still maintains the force transmission path from the chord to the bridge deck. It has good economy and can save more than 40% of steel compared with traditional ballast boxes. Two types of ballast materials are used, the ordinary concrete layer 6 at the bottom has a strong bearing capacity, and the self-compacting cement mortar layer 7 at the top is convenient for pouring through small holes on the top plate to ensure compactness. Moreover, the structure of the ballast area is highly secure. The ordinary concrete of the ordinary concrete layer 6 forms an integral body with the bottom plate 3 after molding, and the first high-strength bolts 8 are connected to the bridge deck beams 1. Even if the first high-strength bolts 8 fail, the pressure The structure of the heavy area can also effectively support the lower wing plate attached to the beam 1 on the bridge deck without falling off. And it also has the characteristics of maintenance-free and strong durability. The closed structure is filled with ordinary concrete and self-compacting cement mortar without maintenance; the steel bridge deck 2 is in the closed structure, the ordinary concrete layer 6 and self-compacting cement mortar layer With the support of 7, the stress is improved and the durability is enhanced. And the outer surface of the closed structure is smooth and tidy, which is convenient for maintenance.

Example 2

This embodiment provides a construction method for the construction of the ballast area of a steel truss girder cable-stayed bridge, which is used to construct the ballast area structure of the steel truss cable-stayed bridge as described in Embodiment 1, comprising the following steps:

S1. Construction bottom plate 3, two side plates 5, two deck beams 1 and steel bridge deck 2 in each ballast area to form a closed structure;

S2. After the main girder of the cable-stayed bridge is closed, firstly pour the ordinary concrete layer 6 into the closed structure, and then pour the self-compacting cement mortar layer 7 .

Among them, the installation of the closed structure can be done in a variety of ways, as follows:

Method 1: In step S1, when constructing each beam section of the ballast area, the steel bridge deck 2 of the beam section of the ballast area, all bridge deck beams 1, and two adjacent bridge deck beams 1 The bottom plate 3 and the side plate 5 between them are assembled to form the whole beam section, which includes several closed structures, and then the beam section is hoisted as a whole;

The first way is to assemble each beam section in the weight zone on the ground. When assembling, install the bottom plate 3 and the side plate 5 on the ground to form several closed structures, and then carry out overall hoisting. This construction method is constructed on the ground. It is safer, but requires a larger assembly site and requires large lifting equipment.

When the construction site of the beam section in the ballast area is limited, or the large-scale lifting equipment cannot be transported to the construction site of the beam section in the ballast area, it is impossible to assemble the beam section of the ballast area on the ground before overall hoisting. Two pairs of base plates 3 and side plates 5 are installed.

The second method is: in step S1, when the steel truss girder is constructed to the girder section in the ballast area, after hoisting the two adjacent bridge deck beams 1, the corresponding two adjacent bridge decks The bottom plate 3 and the side plate 5 are hoisted between the beams 1 to form the closed structure. Mode 2 is a more optimal implementation mode. After hoisting the two adjacent bridge deck beams 1, the bottom plate 3 and the side plate 5 are hoisted in time to form the closed structure, which can avoid being restricted by the construction site, and also There is no need to use large lifting equipment, and the construction steps are simpler.

In this embodiment, when there are the first high-strength bolts 8 and the second high-strength bolts 10 in Embodiment 1, in step S1, the bottom plate 3 and the When the side plate 5 is formed, the first high-strength bolt 8 and the second high-strength bolt 10 are initially screwed. After the construction of the beam section in the ballast area is completed, the first high-strength bolt 8 and the second high-strength bolt 10 are tightened to form a stable closed structure.

After the main girder of the cable-stayed bridge is closed, the ordinary concrete on the bottom layer is ready to be poured. Before pouring, it is necessary to seal the gap between the side plate 5 of the closed structure and the bridge deck beam 1, and between the side plate 5 and the steel bridge deck 2. .

After the sealing treatment is completed, the ordinary concrete on the bottom layer is poured through the manhole, and the ordinary concrete layer 6 adopts full-section layered pouring. In this embodiment, a better implementation mode is adopted. In step S2, the ordinary concrete layer 6 is divided into two layers of construction. First, the first layer 61 is poured on the base plate 3. After the strength of the first layer 61 reaches the standard, the second layer 62 is poured on the first layer 61. During the pouring process of the second layer 62, When the height of the ordinary concrete poured is higher than the bottom level of the manhole 12, first block a part of the bottom of the manhole 12, and then pour ordinary concrete. A part of the manhole 12 is blocked, and then ordinary concrete pouring is carried out, and ordinary concrete is poured in a manner of gradually upwardly blocking the manhole 12 until the second layer 62 is poured, and then the described manhole 12 is completely blocked. Manhole 12; the bearing capacity of the first layer 61 ordinary concrete is effectively utilized, so that the thinner base plate 3 and the first stiffener 4 only need to be able to bear the weight of the first layer 61 ordinary concrete, and the first layer 61 ordinary concrete The steel-concrete structure formed with the bottom plate 3 after the concrete is formed can effectively bear the total weight of the second layer 62 of ordinary concrete and the self-compacting cement mortar layer 7 . The ordinary concrete layer 6 is divided into two layers for construction, so that the thickness of the required bottom plate 3 is thinner, and the strength of the required first stiffener 4 is smaller, which can save steel materials, and at the same time make the bottom plate 3 and the first stiffener 4 installation is easier.

After the strength of the second layer 62 reaches the standard, a pouring hole is opened above the steel bridge deck 2 corresponding to the U-rib 21 and the U-rib 21 or between the U-rib 21 and the bridge deck longitudinal girder 22, and the pouring hole is poured through the pouring hole. The cement mortar layer 7 is compacted until the closed structure is filled. Among them, the size of the pouring hole is 4-6cm, preferably 5cm, and the exhaust pipe and pouring pipe are set, and the micro-expansion self-compacting cement mortar is used to pour with pressure to ensure that the ballast box is fully filled. Pouring the self-compacting cement mortar layer 7 through the pouring hole can fill the closed structure more conveniently, quickly and with high quality, and prevent the corners of the U-rib 21 and the bridge deck stringer 22 from being completely filled. This construction method of manhole 12 combined with small pouring holes can minimize the need to open a large number of larger pouring openings for the structure of the ballast area, ensure the integrity of the structure of the ballast area, and improve the quality of the structure of the ballast area.

After the closed structure is filled, the pouring holes on the steel bridge deck 2 are sealed to complete the construction of the ballast area structure.

In order to test the safety and feasibility of the bottom plate 3 of the structure in the ballast area and the beam 1 of the bridge deck, the calculation and analysis of the stress on the structure in the ballast area were carried out, all of which met the force requirements, and the closed structure can effectively improve the steel structure. The fatigue characteristics of the bridge deck 2 make the bridge deck structure maintenance-free.

Compared with the construction of the existing ballast box, the construction method of the ballast area structure of the steel truss cable-stayed bridge described in this embodiment can safely and quickly construct the ballast of the steel truss cable-stayed bridge in the present invention District structure, its construction is simpler.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (10)

1. the weight zone structure of a steel truss girder cable-stayed bridge, is characterized in that, comprises base plate (3) and two side plates (5), and described base plate (3) and side plate (5) are all arranged on steel Between two adjacent deck beams (1) of the truss, the base plate (3), the two side plates (5), and the corresponding adjacent two deck beams (1) and the The steel bridge deck (2) of the steel truss girder can enclose a closed structure, and the closed structure is filled with ballast bodies. 2. The ballast area structure of the steel truss girder cable-stayed bridge according to claim 1, characterized in that, the lower part of the ballast body is an ordinary concrete layer (6), and the upper part is a self-compacting cement mortar layer (7). 3. the ballast area structure of the steel truss girder cable-stayed bridge according to claim 2, is characterized in that, the height of the top surface of the ordinary concrete layer (6) is not higher than the U rib of the steel bridge deck (2) (21) BOTTOM. 4. the ballast area structure of steel truss girder cable-stayed bridge according to claim 2, is characterized in that, described side plate (5) is provided with manhole (12), and the top of described manhole (12) is higher than On the top surface of the ordinary concrete layer (6), the ordinary concrete layer (6) is poured through the manhole (12). 5. The ballast area structure of the steel truss girder cable-stayed bridge according to any one of claims 1-4, wherein a plurality of first stiffeners (4) are arranged above the bottom plate (3), and the side The inner side of the plate (5) is provided with several second stiffeners (13). 6. The ballast area structure of the steel truss girder cable-stayed bridge according to claim 5, characterized in that, several first stiffeners (4) are arranged along the longitudinal bridge direction, and the first stiffeners (4) The corresponding joint plates (11) of the bridge deck beams (1) are connected by first high-strength bolts (8); the longitudinal bridges of the side plates (5) correspond to the two bridge decks on both sides respectively. The web stiffeners of the tie beams (1) are connected by second high-strength bolts (10). 7. The ballast area structure of the steel truss girder cable-stayed bridge according to claim 5, characterized in that, the thickness of the bottom plate (3) is 10-16mm, and the thickness of the side plate (5) is greater than or equal to 10mm. 8. A construction method of the ballast area structure of the steel truss girder cable-stayed bridge as described in any one of claims 2-7, is characterized in that, comprises the following steps: S1. The bottom slab (3), two side slabs (5), two deck beams (1) and the steel bridge deck (2) are constructed in each ballast area to form a closed structure; S2. After the main girders of the cable-stayed bridge are closed, first pour a layer of ordinary concrete (6) into the closed structure, and then pour a layer of self-compacting cement mortar (7). 9. The construction method of the ballast area structure of the steel truss girder cable-stayed bridge according to claim 8, is characterized in that, in step S2, described common concrete layer (6) is divided into two-layer construction, first in the A first layer (61) is poured on the bottom plate (3), and a second layer (62) is poured on the first layer (61) after the strength of the first layer (61) reaches the standard. 10. The construction method of the ballast area structure of the steel truss girder cable-stayed bridge according to claim 9, characterized in that, in the step S2, pouring the ordinary concrete layer (6) through the manhole (12) , on the side plate (5) of the manhole (12); During the pouring process of the second layer (62), when the height of the poured ordinary concrete is higher than the bottom of the manhole (12), the ordinary concrete is gradually sealed upwards to the manhole (12). Pouring until the completion of the pouring of the second layer (62), and then completely blocking the manhole (12); After the strength of the second layer (62) reaches the standard, a pouring hole is opened in the steel bridge deck (2), and a self-compacting cement mortar layer (7) is poured through the pouring hole until the closed structure is filled, and then The pouring hole is closed.

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