阅读说明：本技术 一种开启桥桥体重心调整施工方法 (Construction method for adjusting gravity center of open bridge body ) 是由 吴昊 崔苗 潘孝金 周会茂 吴庆超 陈万 于 2021-09-29 设计创作，主要内容包括：本发明公开了一种开启桥桥体重心调整施工方法,该方法于开启桥施工期间,在配重段主纵梁下部增加钢管柱作为临时后支撑,桥体安装时,通过分阶段增加配重箱的重量配置,控制全桥桥体重心位置,以保证桥体分段安装过程安全,为保证桥体施工过程中桥体的重心位置控制,在施工前,通过理论计算模拟各施工阶段桥体重心位置的变化,施工过程中,在前支撑结构处设置称重传感器,监测桥体对前支撑转轴结构产生的作用力,测算桥体水平纵向实际重心位置,通过理论计算和现场监测的双控措施避免桥体在施工时产生倾覆等不安全现象,施工后,通过活动配重块与液压油缸的复核情况调整桥体的竖向重心位置,保证桥体重心位置满足桥体运行要求。(The invention discloses a construction method for adjusting the gravity center of an open bridge body, which is characterized in that during the construction of the open bridge, a steel pipe column is added at the lower part of a main longitudinal beam of a counterweight section to be used as a temporary rear support, when the bridge body is installed, the weight configuration of a counterweight box is increased in stages to control the gravity center position of the full bridge body so as to ensure the safety of the subsection installation process of the bridge body, in order to ensure the gravity center position control of the bridge body in the construction process of the bridge body, the change of the gravity center position of the bridge body in each construction stage is simulated through theoretical calculation before construction, a weighing sensor is arranged at a front support structure during construction, the acting force of the bridge body on a front support rotating shaft structure is monitored, the horizontal and longitudinal actual gravity center position of the bridge body is measured and calculated, the unsafe phenomenon such as overturning and the like during the construction of the bridge body is avoided through double control measures of theoretical calculation and on-site monitoring, after the construction, the vertical gravity center position of the bridge body is adjusted through the rechecking condition of a movable counterweight block and a hydraulic oil cylinder, the gravity center position of the bridge body is ensured to meet the operation requirement of the bridge body.)

1. A construction method for adjusting the gravity center of an open bridge body is characterized in that the bridge body comprises a shaft seat structure, a front support structure, a bridge body structure and a weight box, the weight box comprises a main box body and a plurality of boxes embedded in the main box body, the front support structure is provided with a weighing sensor, the bridge body structure comprises a weight section, a bearing section and a cantilever section,

the bridge body installation process comprises the following steps:

s1, installing the shaft seat structure, the front support structure and a frame structure of the weight box, wherein the lower part of the frame structure of the weight box is supported by a temporary support structure;

s2, mounting the beam steel structure of the cantilever section and bridge deck concrete of the bridge body in a segmented manner, and pouring concrete into the weight box in a segmented manner according to the gravity center data of the weighing sensor to form a fixed counterweight block, so that the gravity center of the mounted part of the bridge body is positioned in the range between the front support structure and the temporary rear support;

s3, repeating the steps S1-S2, and installing the opposite-shore bridge body;

s4, respectively adjusting movable balancing weights in the boxes at different positions in the bridge body on two banks to enable the horizontal gravity center of the bridge body to be within a required range;

s5, connecting the bridge bodies on two banks;

s6, debugging the bridge body, and readjusting the number of the movable balancing weights in the cells to enable the vertical gravity center of the bridge body to be located in a required range.

2. The method for adjusting the center of gravity of a bridge body of an open bridge as claimed in claim 1, further comprising a step of adjusting the center of gravity of the bridge body before step S1

Step A1, according to the structural design of the bridge body, counting the gravity centers and the weights of all components of the bridge body, and calculating the number of the movable balancing weights arranged in each cell;

step A2, simulating a component installation process and a concrete pouring process of the bridge body according to the calculation result of the step A1, so that the component installation process and the concrete pouring process are performed in the installation process

(1) The center of gravity of the bridge body is always located in the range between the front support structure and the temporary rear support;

(2) the acting force of the bridge body on the front supporting structure is smaller than the weighing range of the weighing sensor;

and finally determining the installation sequence of the bridge body, the sectional pouring weight of the fixed balancing weights and the number of the movable balancing weights.

3. The method as claimed in claim 1, wherein in step S1, the front end of the weight section is fixedly connected to the main longitudinal beam of the bearing section, the rear end of the weight section and the two ends of the weight box are both disposed on the temporary rear support, and a temporary support platform is disposed under the middle portion of the weight box.

4. The method as claimed in claim 1, wherein the cells are uniformly disposed on an end surface of the main box body away from the cantilever section, the cells are disposed at upper and lower ends of the main box body, respectively, and in step S4, the number of the movable weights in each of the cells at the upper and lower ends is adjusted according to the gravity data of the load cell.

5. The method of claim 1, wherein in step S1, the operation frame, the support frame and the beam steel structure platform are set up in advance in the main pier box of the two banks, the crane platform and the crane assembly are set up in the approach structure of the bridge, the front support structure, the axle seat structure and the bearing segment are hoisted by the crane assembly, and the axle seat structure is precisely aligned and provided with the fastening bolt.

6. The method as claimed in claim 1, wherein in step S2, the deviation between the actual data and the theoretical data of the load cell is checked continuously, the actual gravity position of the bridge is determined, and the single concrete pouring amount of the weight box and the number of the structural members of the beam steel structure to be installed are adjusted.

7. The method as claimed in claim 1, wherein in step S3, the driving system of the installed bridge is completed, the installed bridge is rotated to maintain the opened state, and the half channel is opened until step S3 is completed.

8. The method as claimed in claim 1, wherein in step S5, the middle locking device is disposed at each of the ends of the cantilever sections of the bridges on both sides, the middle locking device comprises a latch locking rod and a latch receiving seat, and when the bridge is closed, the latch locking rod is inserted into the latch receiving seat through a hydraulic push rod to connect the bridges on both sides.

9. The method as claimed in claim 1, wherein in step S6, the front supporting structure is adjusted to fit the support of the bridge body tightly, the span deviation of the bridge body is adjusted to within 10 mm, the span finger-shaped expansion joint is installed, and the number of the movable weight blocks in the cell is adjusted according to the pressure data and stress state of the hydraulic cylinder during jacking, so that the vertical center of gravity of the bridge body is adjusted to within a required range.

10. The method of claim 1, wherein in step S2, the bridge deck concrete is laid and auxiliary structures of the bridge are installed, the auxiliary structures including deck railings, isolation belts and ornaments.

Technical Field

The invention relates to the technical field of municipal bridges, in particular to a construction method for adjusting the gravity center of an open bridge body of an open bridge.

Background

The open bridge is a bridge which can rotate or move part of the bridge body, is usually used for road traffic crossing a river channel or a port, and when the road traffic needs navigation of a large ship, the road traffic is cut off, and the bridge is partially or completely opened to enable the ship on the river channel or the port to pass. The existing common opening bridge opening modes include three modes of horizontal rotation, lifting and vertical rotation, wherein the vertical rotation type opening bridge is a movable bridge which can be opened in a rotary mode on a vertical surface and is formed by a bridge body at one end of a navigation part.

The vertical rotary type opening bridge uses a rotating shaft arranged at a certain point on the self structure as a rotating center, a shaft seat structure support is arranged at the bottom of the vertical rotary type opening bridge as a rotating supporting point of the rotating shaft, a front supporting structure is required to be arranged at the front end of the shaft seat structure support to support the weight of the bridge, and the shaft seat structure support and the front supporting structure are two important supports of the opening bridge. During construction, the gravity center position of the bridge body can be continuously changed along with the installation process of the bridge body, and because the spacing distance between the shaft seat structure support and the front support structure is small, the span of the bridge body is large, and the gravity center of the bridge body continuously moves outwards along with the propulsion of the installation process. The vertical rotation type opening bridge mostly adopts the hydraulic cylinder to stretch out and draw back and open and close of opening the bridge, set up axle bed structure support and hydraulic cylinder movable support and bear the weight of the bridge body jointly when opening, when the bridge body focus is close to axle bed structure support, hydraulic cylinder uses less power can carry out opening and shutting of the bridge body, in case the bridge body focus exceeds the two scope of axle bed structure support and preceding supporting structure will cause the bridge body to topple, and simultaneously, the cross-sectional height of the bridge body is great, when the bridge body was closed, the vertical barycentric position of the bridge body is higher than the pivot position, after the bridge body was opened, the bridge body barycentric position will exceed the scope between axle bed structure support and the hydraulic cylinder movable support, make hydraulic cylinder be in the state that is drawn, lead to opening in-process hydraulic cylinder atress and produce great change, influence life. Therefore, when the bridge is opened for construction, a bridge body gravity center adjusting construction method capable of balancing the bridge body installation progress and the bridge body gravity center is needed.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a construction method for adjusting the gravity center of an open bridge body.

The technical scheme of the invention is as follows:

a construction method for adjusting the gravity center of an open bridge body comprises a shaft seat structure, a front supporting structure, a bridge body structure and a weight box, wherein the weight box comprises a main box body and a plurality of boxes embedded in the main box body, the front supporting structure is provided with a weighing sensor, the bridge body structure comprises a weight balancing section, a bearing section and a cantilever section,

the bridge body installation process comprises the following steps:

s1, installing the shaft seat structure, the front support structure and a frame structure of the weight box, wherein the lower part of the frame structure of the weight box is supported by a temporary support structure;

s2, mounting the beam steel structure of the cantilever section and bridge deck concrete of the bridge body in a segmented manner, and pouring concrete into the weight box in a segmented manner according to the gravity center data of the weighing sensor to form a fixed counterweight block, so that the gravity center of the mounted part of the bridge body is positioned in the range between the front support structure and the temporary rear support;

s3, repeating the steps S1-S2, and installing the opposite-shore bridge body;

s4, respectively adjusting movable balancing weights in the boxes at different positions in the bridge body on two banks to enable the horizontal gravity center of the bridge body to be within a required range;

s5, connecting the bridge bodies on two banks;

s6, debugging the bridge body, and readjusting the number of the movable balancing weights in the cells to enable the vertical gravity center of the bridge body to be located in a required range.

The specific installation process is as follows:

step T1, installing the front supporting structure and a temporary supporting structure, wherein the temporary supporting structure comprises a temporary rear support and a temporary supporting platform;

step T2, mounting the shaft seat structure and the bearing section;

step T3, installing the counterweight segment and a frame structure of the counterweight box;

step T4, according to the gravity center data of the weighing sensor, installing a part of beam steel structure of the cantilever beam, pouring concrete into the weight box and forming a part of fixed balancing weight, so that the gravity center of the installed part of the bridge body is located in the range between the front support structure and the temporary rear support;

step T5, repeating the step T4 according to the gravity center data of the weighing sensor, and keeping the gravity center of the installed part of the bridge body within the range between the front support structure and the temporary rear support until all the beam steel structures are installed;

step T6, paving bridge deck concrete of the cantilever section, pouring concrete into the weight box according to the gravity center data of the weighing sensor to form the rest fixed balancing weight, and keeping the gravity center of the installed part of the bridge body within the range between the front support structure and the temporary rear support;

t7, repeating the steps T1-T6, and installing the bridge body at the opposite shore part;

step T8., adjusting the movable balancing weights in the cells of the bridge body on both sides respectively to make the horizontal gravity center of the bridge body within a required range;

step T9. adjusting the alignment between the bridges on both banks by adjusting the front supporting structure, and connecting the bridges on both banks using a middle locking device disposed on the cantilever section;

and T10, debugging the bridge body, and redistributing the movable balancing weights of the cells according to the debugging and running result of the bridge body so that the vertical gravity center of the bridge body is positioned in a required range.

Wherein, the step T1-the step T3 corresponds to the step S1, the step T4-the step T6 corresponds to the step S2, the step T7 corresponds to the step S3, the step T8 corresponds to the step S4, the step T9 corresponds to the step S5, and the step T10 corresponds to the step S6.

The above construction method for adjusting the center of gravity of the open bridge body further comprises before step T1 (corresponding to before step S1)

Step A1, according to the structural design of the bridge body, counting the gravity centers and the weights of all components of the bridge body, and calculating the number of the movable balancing weights arranged in each cell;

step A2, simulating a component installation process and a concrete pouring process of the bridge body according to the calculation result of the step A1, so that the component installation process and the concrete pouring process are performed in the installation process

(1) The center of gravity of the bridge body is always located in the range between the front support structure and the temporary rear support;

(2) the acting force of the bridge body on the front supporting structure is smaller than the weighing range of the weighing sensor;

and finally determining the installation sequence of the bridge body, the sectional pouring weight of the fixed balancing weights and the number of the movable balancing weights.

In step T1 (corresponding to step S1), the front end of the counterweight section is fixedly connected to the main longitudinal beam of the bearing section, the rear end of the counterweight section and the two ends of the weight box are both disposed on the temporary rear support, and the temporary support platform is disposed below the middle portion of the weight box.

In the construction method for adjusting the center of gravity of the open bridge body, the cells are uniformly arranged on the end surface of the main box body away from the cantilever section, the cells are respectively arranged at the upper end and the lower end of the main box body, and in step T8 (corresponding to step S4), the number of the movable counter weights in each cell at the upper end and the lower end is adjusted according to the center of gravity data of the weighing sensor.

Furthermore, the cell platforms are arranged outside the cells, and platform ladder stands are arranged between the cell platforms and are connected with one another.

According to the construction method for adjusting the gravity center of the open bridge body, the weight box comprises an upper structure and a lower structure, the radial size of the lower structure is smaller than that of the upper structure, and the cross section of the weight box is T-shaped.

Furthermore, both ends and the middle part of the upper structure are respectively and fixedly connected with the main beams of the counterweight section, and the rear end of the lower structure is connected with the temporary support structure.

In step T2 (corresponding to step S1), an operation frame, a support bracket, and a beam steel structure platform are set up in advance in a main pier box at both banks, a crane platform and a crane assembly are set up in an approach structure of the bridge, the front support structure, the axle seat structure, and the bearing section are hoisted by the crane assembly, and the axle seat structure is accurately calibrated and provided with fastening bolts.

In the above construction method for adjusting the center of gravity of the open bridge body, in steps T4 to T6 (corresponding to step S2), the deviation value between the actual data and the theoretical data of the weighing sensor is continuously checked, the horizontal and longitudinal actual center of gravity position of the bridge body is determined, and the single concrete pouring amount of the weight box and the number of the members of the beam steel structure to be installed next time are adjusted.

In the above construction method for adjusting the center of gravity of an open bridge, in step T7 (corresponding to step S3), the drive system of the installed bridge is completed, the installed bridge is rotated to maintain the open state, and a half channel is opened until step T7 is completed (corresponding to step S3).

In step T9 (corresponding to step S5), the middle locking device is disposed at the end of the cantilever section of the bridge body at both banks, the middle locking device includes a latch locking rod and a latch receiving seat, and when the bridge body is closed, the latch locking rod is inserted into the latch receiving seat through a hydraulic push rod to connect the bridge body at both banks.

Further, the bolt locking lever in advance with the pontic fixed connection, close after the pontic, open the bolt locking lever, the accurate positioning is carried out on the scene the steel construction of pontic is gone up the hole and is installed the bolt receiver realizes the pontic centering.

In step T10 (corresponding to step S6), the front support structure is adjusted to be closely attached to the support of the bridge body, the span deviation of the bridge body is adjusted to be within 10 mm, the span finger-shaped expansion joint is installed, and the number of the movable counter weights in the cell is adjusted according to pressure data and stress state of a hydraulic oil cylinder in the jacking process, so that the vertical center of gravity of the bridge body is adjusted to be within a required range.

In the above construction method for adjusting the center of gravity of the open bridge, in step T6 (corresponding to step S2), the bridge deck concrete is laid and the auxiliary structures of the bridge are installed, wherein the auxiliary structures include bridge deck rails, isolation belts and decorations.

According to the scheme, the steel pipe column is additionally arranged at the lower part of the main longitudinal beam of the counterweight section to serve as a temporary support during open bridge construction, and the gravity center position of the full-bridge body is controlled by increasing the weight configuration of the fixed counterweight blocks of the counterweight box in stages during bridge body installation. In order to confirm the gravity center position of the bridge body in the construction process of the bridge body, a weighing sensor is arranged at the front supporting structure, the gravity center position of the bridge body is calculated in each construction stage, the acting force of the bridge body on the shaft seat structure and the front supporting structure is monitored, the gravity center position of the bridge body is calculated and rechecked, the safety of the bridge body is ensured by adopting double control measures of theoretical calculation and field measurement, and the overturning phenomenon of the bridge body during construction is avoided. Similarly, before the bridge body is debugged, the gravity center of the bridge body also needs to be rechecked through theoretical calculation and a weighing sensor, and the jacking force of the hydraulic cylinder before debugging is calculated, so that the smooth debugging is ensured.

Before construction, simulating the change of the gravity center position of the bridge body in each construction stage through theoretical calculation; in the construction process, a weighing sensor is arranged at the front support structure, the acting force of the bridge body on a rotating shaft of the front support structure is monitored, the horizontal and longitudinal actual gravity center position of the bridge body is measured and calculated, and unsafe phenomena such as overturning and the like of the bridge body during construction are avoided through double control measures of theoretical calculation and field monitoring; after construction, the vertical gravity center position of the bridge body is adjusted through rechecking of pressure data and stress states in the jacking process of the movable balancing weights and the hydraulic oil cylinders distributed above and below the weight box. The method simultaneously ensures the gravity center positions of the bridge body in the horizontal direction and the vertical direction so as to meet the opening operation of the bridge body.

In addition, because fixed balancing weight is solidified by the concrete and forms, can balance the pontic weight of the different time quantum of pontic segmentation work progress, guarantee that pontic focus position is stable, prevent the emergence of accident or trouble, can also revise the focus deviation of pontic simultaneously through changing the quantity that sets up movable balancing weight in the cell of different positions in the main tank body, and be favorable to the alignment degree debugging of both sides pontic.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a partially enlarged view of fig. 1.

Fig. 3 is a schematic view of the weight box.

Fig. 4 is a schematic view of the structure of the weight box and the temporary support structure.

Wherein, in the figures, the respective reference numerals:

1. a bridge body; 11. a counterweight segment; 12. a bearing section; 13. a cantilever section; 14. concrete for bridge deck; 15. a front support structure; 16. a shaft seat structure; 17. a weighing sensor;

2. a weight box; 21. fixing a balancing weight; 22. a movable balancing weight; 23. a box; 24. a main box body;

3. temporary rear support; 4. a temporary support platform;

5. a hydraulic cylinder;

6. and a middle locking device.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is 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 of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "fixed" or "disposed" or "connected" to another element, it can be directly or indirectly located on the other element. The terms "upper", "lower", "left", "right", "front", "rear", "bottom", "inner", "outer", and the like indicate orientations or positions based on the orientations or positions shown in the drawings, and are for convenience of description only and not to be construed as limiting the technical solution. "Multi" means two or more unless specifically limited otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

A construction method for adjusting the center of gravity of an open bridge body comprises the steps that as shown in figures 1 and 2, when a bridge body 1 is installed, the weight configuration of a fixed balancing weight 21 of a weight box 2 is increased in stages, the center of gravity of the bridge body 1 is moved backwards, the weight of the bridge body 1 increased due to the progress of the installation process is balanced, in order to confirm the center of gravity position of the bridge body 1 in the construction process of the bridge body 1, a weighing sensor 17 is arranged at a front supporting structure 15, the center of gravity position of the bridge body 1 is calculated in each construction stage, acting force generated by the bridge body 1 to a shaft base structure 16 and the front supporting structure 15 is monitored to calculate and recheck the center of gravity position of the bridge body 1, the safety of the bridge body 1 is guaranteed by adopting double-control measures of theoretical calculation and field measurement, and the overturning phenomenon of the bridge body 1 in the construction process is avoided. Meanwhile, after the bridge bodies 1 at both sides are connected, the number of the movable balancing weights 22 of different cells 23 is adjusted according to the gravity center data of the weighing sensor 17, so that the centering adjustment of the bridge bodies 1 is assisted, and the bridge bodies 1 are smoothly closed.

The bridge body 1 comprises a shaft seat structure 16, a front supporting structure 15, a bridge body 1 structure and a weight box 2, wherein the weight box 2 comprises a main box body 24 and a plurality of boxes 23 embedded into the main box body 24, the front supporting structure 15 is provided with a weighing sensor 17, and the bridge body 1 structure comprises a weight balancing section 11, a bearing section 12 and a cantilever section 13. A fixed balancing weight 21 formed by solidifying concrete is arranged in the weight box 2, a detachable movable balancing weight 22 is arranged in the box 23, and the weight box 2 is arranged below the weight section 11. The axle seat structure 16 and the front support structure 15 are arranged below the bearing section 12, and the cantilever section 13 comprises a beam steel structure and a concrete structure of a bridge deck.

When the bridge body 1 is installed, the axle seat structure 16 serving as a rotation center and a bearing end is installed, then the axle seat structure extends to the upper bearing section 12, the position of a fulcrum of the whole bridge body 1 is determined and stabilized, and meanwhile the front support structure 15 is completed to support the weight of the bearing section 12. Then, a frame structure of the counterweight segment 11 and the counterweight box 2 is installed, on the basis, the bearing segment 12 is extended, a beam steel structure of the cantilever segment 13 is built in a segmented mode, meanwhile, concrete is poured into the counterweight box 2 step by step according to the building progress and gravity center data obtained by the weighing sensor 17 to form a fixed counterweight 21, and the gravity center of the bridge body 1 is maintained in the range between the shaft seat structure 16 and the front support structure 15. When the concrete structure of the cantilever section 13 is laid next, concrete is poured into the weight box 2 step by step according to the gravity data of the weighing sensor 17 to form the remaining fixed counter weight 21, and the gravity of the bridge body 1 is maintained within the range between the shaft seat structure 16 and the front support structure 15. When the structures of the bridge bodies 1 at the two banks are finally connected, the number of the movable counter weights 22 in the cells 23 at different positions is adjusted to adjust the centering degree between the bridge bodies 1.

The open bridge controls the gravity center position of the whole body through the weight box 2, and as shown in fig. 3, the main box body 24 is a frame structure and a plate structure to form a large-scale container. The frame structure comprises longitudinal beam modules and an inner supporting structure, and the inner supporting structure comprises an inner supporting cross beam module and an inner supporting diagonal member. Since the main box 24 has a multi-layer structure, a frame structure is provided between each layer of structure, and the plate structure is laid along the frame structure to form a semi-enclosed structure. The plate structure comprises a bottom plate module and a side plate module, stiffening rib plates are arranged between the plates, and the stiffening rib plates are pulled tightly through the studs to improve the connection strength between the plates.

The boxes 23 are uniformly arranged on one end face, far away from the cantilever section 13, of the main box body 24, the boxes 23 are respectively arranged at the upper end and the lower end of the main box body 24, a box 23 platform is arranged outside the boxes 23, and platform ladder stands are arranged between the box 23 platforms and are connected with one another. In one embodiment, the weight box 2 includes a superstructure and a substructure, the substructure having a radial dimension less than a radial dimension of the superstructure, and the weight box 2 having a T-shaped cross-section. The two ends and the middle part of the upper structure are respectively fixedly connected with a plurality of main beams of the counterweight section 11, and the rear end of the lower structure is connected with the temporary supporting structure. When the structure drives the bridge body 1 to rotate, the weight box 2 and the support structure of the bridge body 1 are not collided, and the gravity center of the bridge body 1 can be moved to the support structure as far as possible.

Pouring concrete in the main box body 24 as the fixed balancing weight 21 that plays main bearing effect, set up metal blocks such as nodular cast iron as detachable modular movable balancing weight 22 in the cell 23 structure, this balancing weight can play the effect of adjusting the focus owing to all set up on the curb plate module of weight box 2 keeping away from pontic 1 one side, makes pontic 1 focus move to the inside of the scope between axle bed structure 16 and preceding supporting structure 15, keeps pontic 1 focus balanced. Because the main weight of weight box 2 is provided by the concrete of fixed balancing weight 21, increases counter weight along with the concrete volume that pours into gradually, consequently, in the work progress, can adjust the concrete volume of pouring into according to the construction progress, makes the inside of bridge 1 focus stable at the bearing structure.

The bridge body 1 installation process comprises the following steps:

and T1, mounting a front support structure 15 and a temporary support structure, wherein the temporary support structure comprises a temporary rear support 3 and a temporary support platform 4. The front end of the counterweight segment 11 is fixedly connected with the main longitudinal beam of the bearing segment 12, the rear end of the counterweight segment 11 and the two ends of the counterweight box 2 are both arranged on the temporary rear support 3, and the temporary support platform 4 is arranged below the middle part of the counterweight box 2.

Before step T1

Step A1, according to the structural design of the bridge body 1, counting the gravity centers and the weights of all the components of the bridge body 1, and calculating the number of the movable balancing weights 22 arranged in each cell 23.

Step A2, simulating the component installation process and the concrete pouring process of the bridge body 1 according to the calculation result of the step A1, so that the component installation process and the concrete pouring process are performed in the installation process

(1) The center of gravity of the bridge 1 is always located in the range between the front support structure 15 and the temporary rear support 3.

(2) The force of the bridge 1 on the front support structure 15 is smaller than the weighing range of the load cell 17.

Finally determining the installation sequence of the bridge body 1, the sectional pouring weight of the fixed balancing weights 21 and the number of the movable balancing weights 22.

And T2, mounting the shaft seat structure 16 and the bearing section 12.

An operation frame, a support bracket and a beam steel structure platform are erected in a main pier box at two banks in advance, a crane platform and a crane assembly are erected on an approach structure of the bridge body 1, a front support structure 15, an axle seat structure 16 and a bearing section 12 are hoisted through the crane assembly, and the axle seat structure 16 is accurately calibrated and provided with fastening bolts.

The open bridge is mostly of a beam steel structure and needs to be hoisted through a crane. In the construction process, an operation frame and a support bracket are erected in main pier boxes on two sides, a beam steel structure platform and a slope frame are erected on a prestressed concrete approach bridge floor, a crawler of a crane is made to ascend to the beam steel structure platform through the slope frame, and local concrete is structurally reinforced during the construction of the approach bridge structure. The foundation supporting frame of the approach bridge structure part is completed by erecting the supporting bracket, the operating frame and the beam steel structure platform, so that a main supporting structure of the bridge body 1 is formed on one hand, and a moving platform of a transport tool is erected on the other hand. In addition, the installation of the hydraulic oil cylinder 5, the shaft seat structure 16 and other steel supporting components is completed simultaneously in the process, the shaft seat structure 16 and the front supporting structure 15 are main supporting parts of the bridge body 1 and are also setting reference positions of the gravity center of the bridge body 1, and therefore after the shaft seat structure 16, the front supporting structure 15 and the relevant steel supporting structures are installed, accurate calibration needs to be carried out and fastening bolts need to be set. And the hydraulic cylinder is temporarily fixed, and the surface is covered and protected. On the other hand, since the bridge body 1 is erected from the main pier box, the components such as the weight box 2, the related steel supporting components, and the main beam of the rear section of the beam steel structure are placed on the beam of the supporting bracket in advance.

The beam steel structure of the bearing section 12 is erected above the front support structure 15 and the axle seat structure 16 as references. The structure is the second section of the bridge 1, while the first section of the bridge 1, i.e. the counterweight section 11, is temporarily erected, which is temporarily filled with a beam steel structural platform. The reason for setting up the bearing section 12 first instead of the counterweight section 11 is to stabilize the center of gravity and the main bearing portion of the bridge 1 first. For the opening bridge, the cantilever section 13 at the front end and the counterweight section 11 at the rear end are both structurally and pressure-center-of-gravity arranged in the range between the front support structure 15 and the axle seat structure 16, so that the arrangement of the first bearing section 12 for stabilization is not flexible.

The installation of the bearing section 12 needs to install a temporary support and a jack in advance, a longitudinal beam of the bearing section 12 is slowly lowered from the middle of two rails of a beam steel structure platform, the front end of the longitudinal beam is placed on the upper surface of the front temporary support, the position of the longitudinal beam is slowly adjusted at the rear end of the longitudinal beam, the center line of the longitudinal beam and the center of a trunnion support are kept coincident, and the longitudinal beam is safely and nondestructively placed in a precisely calibrated shaft seat structure 16. Adjusting a jack, installing a weighing sensor 17 at the front supporting structure 15, and removing the temporary support after rechecking the axis elevation of the main beam of the bearing section 12 without error.

And T3, installing the frame structures of the counterweight segment 11 and the counterweight box 2.

The temporary support structure of the counterweight section 11 and the counterweight box 2 is arranged in advance, when the first section (counterweight section 11) is hoisted, the front end of a main beam of the temporary support structure is connected with a main beam bolt of the second stage (bearing section 12), so that the counterweight section 11 is connected with the bearing section 12, and the beam steel structure installation of the bridge body 1 in the range of the front support structure 15 and the axle seat structure 16 is completed. Only the frame structure of the weight box 2 needs to be installed and erected below the weight section 11, the longitudinal beam module, the inner support cross beam module and the inner support diagonal support member are fixedly connected, and meanwhile, the side plate module and the bottom plate module are arranged. As shown in fig. 4, the weight box 2 is integrally erected on the temporary support structure, the temporary rear supports 3 are arranged on the middle recessed portion and the two side edges of the weight box 2, and the weight box 2 is integrally arranged on the temporary support platform 4.

And T4, according to the gravity center data of the weighing sensor 17, installing a part of beam steel structure of the cantilever beam, pouring concrete into the weight box 2 and forming a part of fixed counterweight 21, so that the gravity center of the installed part of the bridge body 1 is positioned in the range between the front support structure 15 and the temporary rear support 3.

And T5, repeating the step T4 according to the gravity center data of the weighing sensor 17, and keeping the gravity center of the installed partial bridge body 1 within the range between the front support structure 15 and the temporary rear support 3 until the installation of all beam steel structures is completed.

In this application, the installation of the cantilever section 13 is divided into two parts, namely a third section and a fourth section, and in practical use, the erection of the cantilever section 13 can be divided into a plurality of sections according to the length. And continuously splicing the beam steel structure of the third section by taking the main beam of the bearing section 12 as a reference, and finally completing the splicing of the beam steel structure of the third section.

After the first part of the bridge section is completed, the whole gravity center of the bridge body 1 moves forwards, and the existing gravity center position can be obtained through the arrangement of the weighing sensor 17 in a sensing mode. In order to ensure that the gravity center of the bridge body 1 is still in the range between the front supporting structure 15 and the shaft seat structure 16 in the construction process of the next stage, concrete is poured into the weight box 2 arranged at the rear end of the bridge body 1. According to the measurement data of the weighing sensor 17, the pouring amount of the balance weight concrete is determined after gravity center calculation, the data and the theoretical deviation value of the weighing sensor 17 are rechecked before and after pouring, and the next step of component analysis and component installation quantity adjustment are carried out.

And T6, paving bridge deck concrete 14 of the cantilever section 13, pouring concrete into the weight box 2 according to the gravity center data of the weighing sensor 17 to form a residual fixed counterweight 21, and keeping the gravity center of the installed part of the bridge body 1 within the range between the front support structure 15 and the temporary rear support 3. And (3) laying bridge deck concrete 14 and simultaneously installing auxiliary structures of the bridge body 1, wherein the auxiliary structures comprise bridge deck railings, isolation belts and decorations.

In steps T4 to T6, the deviation value between the actual data and the theoretical data of the load cell 17 is continuously checked, the actual gravity center position of the bridge body 1 in the longitudinal direction with respect to the horizontal plane is determined, and the amount of concrete poured in one time by the weight box 2 and the number of members of the beam steel structure or the length of concrete to be laid in the next step are adjusted. During design, the overall center of gravity can be analyzed through mechanical software, so that the number of the components mounted on the cantilever section 13, the weight of concrete and the pouring amount of concrete of the weight box 2 are adjusted each time, and the center of gravity of the bridge body 1 is within the range between the front support structure 15 and the shaft seat structure 16 in the mounting process. In actual construction conditions, various changing factors exist, so the weighing sensor 17 is arranged to monitor the gravity center of the bridge body 1 in real time, flexibly adjust the number of mounting components, the length of the built cantilever section 13 and the concrete pouring amount each time, and keep the gravity center of the bridge body 1 in the range between the front supporting structure 15 and the shaft seat structure 16 without deviating the cantilever section 13 and the counterweight box 2.

And T7, repeating the steps T1-T6, and installing the opposite-shore part bridge body 1. After the beam steel structure installation of unilateral pontic 1 is accomplished, demolish beam steel structure platform and remove to the installation of opposite bank to demolish the crane support, utilize pontic 1 structure to erect the bed-jig, accomplish vestibule ground concatenation, accomplish whole promotion.

Considering the passage of the navigation channel, when the cantilever section 13 part of the structure of the opposite-shore bridge body 1 is installed, the hoisting is suspended, and the debugging of the installed bridge body 1 is completed successfully. After completion, under the drive of the hydraulic oil cylinder 5 and a hydraulic system, the shaft seat structure 16 is used as a rotation center, the unilateral bridge body 1 is rotated, a half-side channel is opened, the unilateral bridge body 1 is kept in an open state, a ship can conveniently pass through, and meanwhile, the installation of the structure of the opposite-shore bridge body 1 is completed until the debugging of the opposite-shore bridge body 1 is completed.

Step T8. adjusts the movable weights 22 in the cells 23 of the two-bank bridge 1 so that the horizontal center of gravity of the bridge 1 is within the desired range.

After the bridge body 1 on both sides is finished, the number and the positions of the movable balancing weights 22 are preliminarily set according to the gravity center data of the weighing sensor 17, so that the horizontal gravity center of the bridge body 1 is located in a required range. After the movable balancing weight 22 is set, the weighing sensor 17 is removed, and the working state of the hydraulic oil cylinder 5 is tested. In this step, the stress state of the bridge body 1 is not completely reasonable, and the vertical center of gravity of the bridge body 1 is not accurately set.

Step T9. adjusts the alignment between the two shore bridges 1 by adjusting the front support structure 15, using the middle locking device 6 provided on the cantilever section 13 to connect the two shore bridges 1.

The tip of the cantilever section 13 of the both sides pontic 1 all sets up middle part locking device 6, and middle part locking device 6 includes bolt locking lever and bolt receiving seat, and when pontic 1 closed, insert the bolt locking lever in the bolt receiving seat through hydraulic push rod, connect the both sides pontic 1. The bolt locking lever is fixed connection with the bridge body 1 in advance, and after closing the bridge body 1, opens the bolt locking lever, and accurate positioning is carried out on the scene, and system hole and installation bolt receiving seat realize the bridge body 1 centering degree on the steel construction of bridge body 1. In each stage of the installation of the bridge body 1 and the intermediate locking stage, the axis deviation of the bridge body 1 can be measured and adjusted, and the axis deviation result is detected after the structure is installed.

And T10, debugging the bridge body 1, and redistributing the movable balancing weights 22 of the cells 23 according to the debugging operation result of the bridge body 1 so that the vertical center of gravity of the bridge body 1 is in a required range. Through adjusting the front supporting structure 15, the front supporting structure 15 is tightly attached to the support of the bridge body 1, the midspan deviation of the bridge body 1 is adjusted to be within 10 millimeters, and the midspan finger-shaped expansion joint is installed.

In a specific embodiment, the weight box 2 is divided into an upper structure and a lower structure, the cells 23 are uniformly distributed in the upper and lower structures, and in step T8, the number of the movable weights 22 in each cell 23 at the upper and lower ends is adjusted according to the gravity data of the load cell 17, so as to preliminarily determine the required number and position of the movable weights 22, which is beneficial to realizing more accurate gravity center adjustment in step T10. In the step T10, the synchronization condition of the hydraulic oil cylinder 5 and the jacking stress condition of the hydraulic oil cylinder 5 are adjusted, and the number of the movable counter weights 22 arranged in the upper and lower two-part cells 23 is adjusted according to the jacking stress data of the hydraulic oil cylinder 5, so that the jacking force of the hydraulic oil cylinder 5 reaches the design requirement, and the adjustment of the vertical position of the gravity center of the bridge body 1 is completed.

Due to the influences of factors such as bridge span stress deformation, temperature difference, machining errors and the like, uncertainty exists in elevation centering after the bridge is opened on two sides and installed, and accurate closure of the bridge body 1 is guaranteed through rough adjustment and fine adjustment of elevation difference. Coarse adjustment of elevation difference: the elevation of the front supporting structure 15 is accurately adjusted through the adjusting base plate, the front supporting structure 15 is tightly attached to a lower support of the bridge body 1, the span height difference is adjusted to 10 mm, then the span middle finger-shaped expansion joint is installed, the bridge deck adjusting section is reserved for concrete pouring, and meanwhile, the distribution of the spheroidal graphite cast iron movable balancing weights 22 of the weight box 2 is completed.

The compartment 23 of the weight box 2 can be filled with a ductile iron movable weight 22. Because the side plate modules of the weight box 2 are all arranged at one end of the weight box 2 far away from the cantilever section 13 and are arranged in a single surface, the weight can be finely adjusted through the movable balancing weight 22 with smaller mass, and the weight which can be born by manpower can be adjusted. In addition, the span of the cells 23 on the side plate module is consistent with the transverse span of the bridge body 1, the gravity center of the bridge body 1 is transversely adjusted by changing the number of movable balancing weights 22 in each cell 23, the deflection of the bridge body 1 is transversely adjusted, and the height difference between the middle spans is gradually reduced to the range of 10 millimeters.

Fine adjustment of elevation difference: the bolt lock rod part of the middle locking device 6 is fixedly installed with the bridge main body in advance, and when the bridge span on both sides is in a normal closing state, the bolt lock rod is opened, and site accurate positioning, hole making and bolt receiving seat installation are carried out, so that accurate centering is realized.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.