A built-in instant closure device for large-span arch bridges

Abstract

The present invention provides a built-in instant closure device for a large-span arch bridge, which belongs to the technical field of arch bridge closure, and includes a first main chord tube, a butt sleeve and a second main chord tube, a first quick connection device is provided inside the connection port of the first main chord tube, a second quick connection device is provided inside the connection port of the second main chord tube, the butt sleeve is connected at the connection port of the second main chord tube and the first main chord tube, and the first quick connection device is connected to the second quick connection device. The present invention has a fast closure speed, and the built-in instant closure connection structure can quickly complete the closure of the arch rib, reducing the time and risk of closure, and is easy to operate. The device is easy to operate, and only a small number of workers and equipment are needed to complete the full bridge closure of the arch rib, reducing costs and risks.

Description

Technical Field

[0001] The invention relates to the technical field of arch bridge closure, and in particular to a built-in instant closure device for a large-span arch bridge. Background Art

[0002] The traditional closure method uses steel plates or steel sections to weld and position the chord tube, which has the problems of large welding volume and long time. In addition, the arch rib cantilever is long, and the linear shape changes greatly due to temperature. Incomplete welding or insufficient welding volume will lead to locking failure. The closure method also has the problems of insufficient joint strength and low installation accuracy, which seriously affects the overall stability and safety of the arch bridge. The closure method requires a large number of welding operations on site, with a long construction period and high risks. It also requires a large amount of manpower and material resources, which increases the cost and difficulty of the project.

[0003] At present, the development of arch bridge closure locking technology mainly adopts prestressing technology and welding technology. Prestressing technology can achieve faster closure, but the displacement and deformation of the arch bridge after closure are difficult to control, affecting the quality and safety of bridge engineering. Traditional welding technology has the above problems and is not efficient, safe and stable enough. Summary of the invention

[0004] The purpose of the present invention is to provide a built-in instantaneous joint closing device for a large-span arch bridge, so as to solve the technical problems of large welding amount and long time in the existing traditional joint closing method.

[0005] The closure of the main arch ring of an arch bridge is a key process for realizing the transformation of the main arch ring structure's force system. It has high safety risks, high timeliness requirements, and strict precision requirements. How to achieve instantaneous high-precision closure is an issue worthy of study in arch bridge construction.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A built-in instant closure device for a large-span arch bridge comprises a first main chord tube, a butt sleeve and a second main chord tube, wherein a first quick connection device is arranged inside the connection port of the first main chord tube, a second quick connection device is arranged inside the connection port of the second main chord tube, the butt sleeve is connected to the connection port of the second main chord tube and the first main chord tube, and the first quick connection device is connected to the second quick connection device.

[0008] Furthermore, the first quick connection device and the second quick connection device are connected by providing a connection device, and two ends of the connection device are respectively connected to two ends of the first quick connection device and the second quick connection device.

[0009] Furthermore, the connecting device is configured as a connecting plate, and a plurality of bolt holes are provided at both ends of the connecting plate. Bolt holes are provided at both ends of the first quick connecting device and the second quick connecting device, and bolts are provided to pass through the connecting plate and both ends of the first quick connecting device and the second quick connecting device for fixing.

[0010] Further, the first quick connection device includes a plurality of first main chord tube inclined plates, first main chord tube side plates, a first main chord tube inclined plate connecting block, a first main chord tube inclined plate merging connecting plate and a first main chord tube pad. The plurality of first main chord tube inclined plates are inclinedly arranged in the first main chord tube, and the first main chord tube inclined plates are spaced apart from each other. The plurality of first main chord tube inclined plates form a conical structure. The first main chord tube inclined plate connecting block is arranged on the inner side of the conical top formed by the plurality of first main chord tube inclined plates. The first main chord tube inclined plate connecting block connects the plurality of first main chord tube inclined plates into one. The first main chord tube inclined plate merging connecting plate is arranged at the ends of the plurality of first main chord tube inclined plates and is connected to all the first main chord tube inclined plates. The first main chord tube pad is arranged at the outer end of the first main chord tube inclined plate merging connecting plate. The first main chord tube side plates are arranged on both sides of the first main chord tube pad and are respectively connected to the first main chord tube pad and the first main chord tube inclined plate merging connecting plate.

[0011] Further, the second quick connection device includes a plurality of second main chord tube inclined plates, second main chord tube side plates, second main chord tube inclined plate connecting blocks, second main chord tube inclined plate merging connecting plates and second main chord tube pads. The plurality of second main chord tube inclined plates are obliquely arranged in the second main chord tube, and the second main chord tube inclined plates are spaced apart from the second main chord tube inclined plates. The plurality of second main chord tube inclined plates form a conical structure. The second main chord tube inclined plate connecting blocks are arranged on the inner side of the conical top formed by the plurality of second main chord tube inclined plates. The second main chord tube inclined plate connecting blocks connect the plurality of second main chord tube inclined plates into one. The second main chord tube inclined plate merging connecting plate is arranged at the ends of the plurality of second main chord tube inclined plates and is connected to all the second main chord tube inclined plates. The second main chord tube pad is arranged at the outer end of the second main chord tube inclined plate merging connecting plate. The second main chord tube side plates are arranged on both sides of the second main chord tube pad and are respectively connected to the second main chord tube pad and the second main chord tube inclined plate merging connecting plate.

[0012] Furthermore, the second main chord tube pad and the first main chord tube pad are pre-set with a plurality of bolt holes, and the connecting plate is provided with a plurality of connecting holes. The bolt holes at both ends of the connecting plate correspond one-to-one to the bolt holes on the second main chord tube pad and the first main chord tube pad, and bolts are set to pass through and fix the arrangement.

[0013] Furthermore, the specific process of closure is as follows:

[0014] Cutting of the connection plate of the joint: According to the design requirements, the connection plate of the joint needs to be cut according to the measured length. The connection plate can be processed and cut after both sides are installed, and it is hoisted separately to the joint port of each chord for installation, which squeezes the joint time and is not conducive to the realization of instantaneous joint. According to the measured linear shape of the installed segment combined with the construction simulation analysis of the finite element software, the cutting length of the connection plate is predicted, and it is hoisted when the last segment is hoisted, saving the joint construction time. The specific process of the connection plate of the inner upper chord joint is as follows: the cutting calculation process is to use Midas The Civil finite element software analyzes the construction phase of the arch rib hoisting based on the optimization calculation method of one-time tensioning construction. Considering the tangential displacement, the difference in mileage of the ports of the upper chord pipes on the left and right sides of the two banks is calculated. The measured mileage of the ports on one bank is superimposed on the simulated mileage difference to obtain the estimated mileage of the ports on the other bank. The measured mileage of the ports on both banks is subtracted to obtain the length of the embedded section of the joint section. According to the joint structure design drawing, the embedded section is longer than the connecting plate, so the length of the proposed material is obtained by subtracting the length of the connecting plate. Since only the other bank is not installed and there is 80mm reserved space on both sides of the connecting plate, the calculated deformation of the other bank calculated by the construction simulation has a fixed error with the actual deformation, which can still meet the construction material cutting needs. Considering that it is more reliable, 30-40mm more material is cut on the basis of the estimate;

[0015] Determining the timing of closure: The main arch closure construction is carried out during the period of the day when the temperature is the lowest and most stable. It is necessary to continuously observe the temperature and linear changes in the early stage of closure. The best time for closure is determined by analyzing the changing rules of temperature and linearity. Temperature sensors are installed on the main arch chord tubes and the data is connected to the monitoring cloud platform to monitor the temperature changes of the main arch in real time. The measurement robot automatically searches for measurement control points and automatically saves measurement data to monitor the linear changes of the main arch around the clock. The above observation methods provide measured data support for the selection of the timing of closure.

[0016] Linear shape fine-tuning: In order to improve the linear shape accuracy of the joint and reduce the relative linear shape deviation of the corresponding segments on both sides, the linear shape fine-tuning is carried out on the two segments installed last on both sides. For the side installed first, observe the temperature and linear shape change law of the arch ribs from 1:00 to 6:00 in the morning, draw temperature and linear shape curves, and fine-tune the absolute linear shape according to the theoretical linear shape at the joint temperature. Then install the other side, and fine-tune the linear shape based on the relative deviation of the two sides. The relative deviation is controlled within 5mm, and then install the wind brace. The installation process on both sides is the same, but the relative deviation of the later installation side needs to be controlled within 2mm. After the later installed wind brace is installed in place, only punch nails and ordinary bolts for temporary fixing are installed. High-strength bolts are installed after the joint is closed. If the subsequent joint end is difficult to adjust, the wind brace is released before adjustment, so as to reserve adjustment means for subsequent adverse situations.

[0017] Positioning of short joints and matching holes of connecting plates: Cutting and drilling of I-beams of short joints are carried out according to the design. The short joints of the south bank are pre-welded on the connecting plate of the inclined plate. The short joints of the north bank are not installed for the time being and can be hoisted with the arch ribs. After the north bank is installed in place and the linear shape is adjusted, the reaction seats are welded on the chords at both ends of the joint mouth in advance, and the hand chain hoists are hung crosswise. When the joint temperature is reached, they are gradually tightened to temporarily lock the arch ribs, and then positioned and welded on the connecting plate of the inclined plate. The elevation and axis of the short joints of the south bank must be kept in smooth connection. The filling welding can be carried out during the day. The hand chain hoists need to be completely released during the day to avoid breaking during the daytime temperature rise.

[0018] After positioning, recheck and calculate whether the length of the joint connection plate meets the actual needs. If not, cut it on the arch in time and mark the position of the connection plate holes;

[0019] Locking of the closure and unloading of the cladding: Continuously observe the temperature and linear change patterns the next night. When the temperature is the same as that during the hole matching and the linear shape is close to the theoretical linear shape, gradually tighten the hand chain hoist to temporarily lock the arch ribs and quickly tighten the high bolts. At a constant temperature, complete the tightening of all high bolts, and complete the tightening of wind brace high bolts during the day;

[0020] When the joint is at the closure temperature, measure the actual size of the closure mouth and proceed simultaneously with the cutting of the connecting plate to determine the size of the upper and lower chord tube docking sleeves, cut, install and weld, and complete the welding of the arch rib cover plate.

[0021] The present invention has the following beneficial effects due to the adoption of the above technical solution:

[0022] The invention has a fast closure speed, and the built-in instant closure connection structure can quickly complete the closure of the arch ribs, reducing the time and risk of closure and is easy to operate. The device is easy to operate and only requires a small number of workers and equipment to complete the closure of the entire bridge of arch ribs, reducing costs and risks. It is stable and reliable. The built-in instant closure connection structure has high stability and reliability, can ensure the quality and safety of the arch bridge, and is environmentally friendly and energy-saving. Compared with traditional welding methods, the built-in instant closure connection structure is more friendly to the environment and personnel safety, and can save energy and reduce pollution. The super-large bridge successfully achieved the main arch closure posture locking within 2 days through the above means and measures, and the closure efficiency is fast and the locking accuracy is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The invention relates to a built-in instant closure device for a large-span arch bridge.

[0024] Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention without the butt sleeve.

[0025] Figure 3 This is a graph of the linear observation data of the arch ribs in the early stage of closure of the present invention.

[0026] In the accompanying drawings, 1-first main chord tube, 2-butting sleeve, 3-second main chord tube, 4-connecting plate, 5-bolt, 6-first main chord tube inclined plate, 7-first main chord tube side plate, 8-first main chord tube inclined plate connecting block, 9-first main chord tube inclined plate converging connecting plate, 10-first main chord tube pad, 11-second main chord tube side plate, 12-second main chord tube inclined plate, 13-second main chord tube inclined plate connecting block, 14-second main chord tube inclined plate converging connecting plate, 15-second main chord tube pad. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are only for the purpose of enabling the reader to have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be implemented even without these specific details.

[0028] like Figure 1 As shown, a built-in instant closure device for a large-span arch bridge includes a first main chord tube 1, a butt sleeve 2 and a second main chord tube 3. A first quick connection device is arranged inside the connection port of the first main chord tube 1, and a second quick connection device is arranged inside the connection port of the second main chord tube 3. The butt sleeve 2 is connected to the connection port of the second main chord tube 3 and the first main chord tube 1, and the first quick connection device is connected to the second quick connection device.

[0029] The first quick connection device and the second quick connection device are both configured as follows: The inner lining plate is the main force-bearing component and is the main component for connecting the arch rib. The inner lining plate is made of high-strength steel, and the mechanical and chemical properties of the material meet national standards and bridge design requirements. The diameter and wall thickness of the inner lining plate can be adjusted and designed according to actual needs to meet different engineering requirements.

[0030] The pad is a component used to fill the gap between the connecting plate and the rib plate to ensure the tightness and stability of the connection. The material of the pad can be selected according to actual needs, usually high temperature resistant and high strength steel is used to ensure its durability and stability.

[0031] The connecting plate is a component used to connect the arch rib pads on both sides. The material of the connecting plate is the same high-strength steel as the lining plate to ensure the strength and stability of the connection. The length of the connecting plate can be measured and cut according to actual needs to ensure the precision and accuracy of the connection.

[0032] High-strength bolts are used to lock the main fixings of the connecting plates on both sides. They are made of high-strength and high-precision bolt materials to ensure the strength and stability of the connection. The high-strength bolts need to be tightened quickly under appropriate joint conditions to ensure their joint accuracy and stability.

[0033] In the embodiment of the present invention, the first quick connection device and the second quick connection device are connected by providing a connection device, and two ends of the connection device are respectively connected to two ends of the first quick connection device and the second quick connection device.

[0034] In the embodiment of the present invention, the connecting device is configured as a connecting plate 4, and a plurality of bolt holes are provided at both ends of the connecting plate 4. Bolt holes are provided at both ends of the first quick connecting device and the second quick connecting device. Bolts are provided to pass through the connecting plate 4 and both ends of the first quick connecting device and the second quick connecting device for fixing.

[0035] In the embodiment of the present invention, the first quick connection device includes a plurality of first main chord tube inclined plates 6, a first main chord tube side plate 7, a first main chord tube inclined plate connection block 8, a first main chord tube inclined plate converging connection plate 9 and a first main chord tube pad 10. The plurality of first main chord tube inclined plates 6 are obliquely arranged in the first main chord tube 1, the first main chord tube inclined plates 6 are spaced apart from each other, the plurality of first main chord tube inclined plates 6 form a conical structure, and the first main chord tube inclined plate connection block 8 is arranged on the plurality of first main chord tube inclined plates 6, a first main chord tube inclined plate connecting block 8 connects a plurality of first main chord tube inclined plates 6 into one, a first main chord tube inclined plate merging connecting plate 9 is arranged at the ends of a plurality of first main chord tube inclined plates 6 and is connected to all the first main chord tube inclined plates 6, a first main chord tube pad 10 is arranged at the outer end of the first main chord tube inclined plate merging connecting plate 9, and a first main chord tube side plate 7 is arranged on both sides of the first main chord tube pad 10 and is respectively connected to the first main chord tube pad 10 and the first main chord tube inclined plate merging connecting plate 9.

[0036] In the embodiment of the present invention, the second quick connection device includes a plurality of second main chord tube inclined plates 12, a second main chord tube side plate 11, a second main chord tube inclined plate connection block 13, a second main chord tube inclined plate converging connection plate 14, and a second main chord tube pad 15. The plurality of second main chord tube inclined plates 12 are obliquely arranged in the second main chord tube 3, and the second main chord tube inclined plates 12 are spaced apart from each other. The plurality of second main chord tube inclined plates 12 form a conical structure. The second main chord tube inclined plate connection block 13 is arranged on the plurality of second main chord tube inclined plates. On the inner side of the conical top formed by the second main chord tube inclined plate connecting block 13, a plurality of second main chord tube inclined plates 12 are connected as a whole. A second main chord tube inclined plate merging connecting plate 14 is arranged at the ends of a plurality of second main chord tube inclined plates 12 and is connected to all the second main chord tube inclined plates 12. A second main chord tube pad 15 is arranged at the outer end of the second main chord tube inclined plate merging connecting plate 14. A second main chord tube side plate 11 is arranged on both sides of the second main chord tube pad 15 and is respectively connected to the second main chord tube pad 15 and the second main chord tube inclined plate merging connecting plate 14.

[0037] In the embodiment of the present invention, the second main chord tube pad 15 and the first main chord tube pad 10 are pre-set with a plurality of bolt holes, and the connecting plate 4 is provided with a plurality of connecting holes. The bolt holes at both ends of the connecting plate 4 correspond one-to-one to the bolt holes on the second main chord tube pad 15 and the first main chord tube pad 10, and bolts are provided to pass through and fix them.

[0038] The specific construction process is as follows:

[0039] The Wujiang Bridge on Deyu Expressway is the controlling project of the entire Deyu Expressway in Guizhou. It is 1,834 meters long, with a main bridge span of 504 meters. It is a top-bearing steel tube concrete truss arch. It is divided into 15 sections from the column foot to the arch crown. The arch rib sections are numbered GL1 to GL15. There are 60 sections in the whole bridge, and the maximum lifting weight of the sections is 157 tons. The diameter of the arch rib chord is 1.4 meters. C70 self-compacting micro-expansive concrete is poured into the tube. K braces and X braces are set between the arch ribs. The arch crown joint adopts a built-in instantaneous joint connection structure, which is mainly composed of I-beam short joints on both sides and the middle connection plate. After all the sections are installed in place, the arch rib line shape is adjusted and the two ends of the joint are quickly connected with high-strength bolts to achieve the main arch closure of the whole bridge.

[0040] Cutting of the connection plate of the joint: According to the design requirements, the connection plate of the joint needs to be cut according to the measured length. Therefore, the connection plate can only be processed and cut after the GL15 on both sides is installed, and it must be hoisted separately to the joint port of each chord for installation, which squeezes the joint time and is not conducive to achieving instantaneous jointing. According to the measured linear shape of the installed segment combined with the construction simulation analysis of the finite element software, the cutting length of the connection plate is predicted, and it is hoisted when the last segment is hoisted, which can save the joint construction time. The following takes the connection plate of the inner upper chord joint as an example to introduce its cutting calculation process.

[0041] The construction phase analysis of the arch rib hoisting was carried out by using the Midas Civil finite element software based on the one-time tensioning construction optimization calculation method. Taking into account the tangential displacement [1], the difference in the mileage of the upper chord port on the left and right sides of the north bank GL14 and the north bank GL15 is 12.646m and 12.645m.

[0042] The measured mileage of the upper port of GL14 on the north bank is superimposed on the difference of the simulated mileage calculation to obtain the estimated mileage of the upper port of GL15 on the north bank, which is subtracted from the measured mileage of the port of GL15 on the south bank to obtain the length of the patch section of the joint section. According to the joint structure design drawing, the patch section is 20mm longer than the connecting plate, so subtracting 20mm is the length to be cut. Since only GL15 on the north bank has not been installed, and there is 80mm of reserved space on both sides of the connecting plate, even if the calculated deformation of GL15 on the north bank calculated by the construction simulation has a certain error with the actual deformation, it can still meet the construction cutting needs. Considering more reliable, 30-40mm more material can be cut based on the above estimate.

[0043] Table 1 Calculation table of connecting plates to be cut

[0044]

[0045] Determining the timing of closure: The main arch closure is usually carried out during the period of the day when the temperature is the lowest and relatively stable. Therefore, it is necessary to continuously observe the temperature and linear changes in the early stage of closure, and determine the best time for closure by analyzing the changing rules of temperature and linearity. By installing temperature sensors on the main arch chord tubes and connecting the data to the monitoring cloud platform, the temperature changes of the main arch can be monitored in real time; the Leica TS60 measurement robot can automatically search for measurement control points and automatically save measurement data to monitor the linear changes of the main arch around the clock. The above observation methods provide measured data support for the selection of the timing of closure.

[0046] Taking Wujiang Bridge as an example, according to the temperature observation data before the joint closure, the arch rib temperature gradually increased from 8 am to 2 pm, reaching a peak between 2 pm and 6 pm, averaging between 40°C and 50°C. The temperature gradually decreased from 6 pm to around 12 midnight, reaching the lowest temperature from 1 am to 6 am the next day, averaging between 24°C and 26°C, and basically remained stable. At the same time, the arch rib temperature during this period was consistent with the ambient temperature. According to the arch rib linear observation data of the Leica TS60 measuring robot, the arch rib linear shape changed greatly from 6 am to 12 pm during the day, and the linear shape tended to be stable from 12 pm to 6 am the next day. According to the weather forecast, the lowest temperature at night on August 5 (the proposed joint locking time) was 25°C. Combined with the recent temperature observation data and arch rib linear observation data, it is planned to select 1 am to 6 am as the time period for linear fine-tuning and joint locking, and the joint temperature is 25°C.

[0047] Line shape fine-tuning: In order to improve the line shape accuracy of the joint and reduce the relative line shape deviation of the corresponding segments on both sides as much as possible, the line shape fine-tuning is carried out on the two segments installed last on both sides.

[0048] For the GL14 installed first, observe the temperature and linear changes of the arch ribs between 1:00 and 6:00 in the morning, draw temperature and linear curves, and fine-tune the absolute linear shape based on the theoretical linear shape at the closure temperature. For the GL14 installed later, fine-tune the linear shape based on the relative deviation between the two banks, control the relative deviation within 5mm, and then install the wind bracing.

[0049] The installation process of GL15 on both sides is similar, but the relative deviation of GL15 on the rear installation side needs to be controlled within 2mm. After the GL15 wind brace is installed in place, only punch nails and ordinary bolts for temporary fixation are installed. High-strength bolts are installed after the joints are connected. Considering that if the subsequent joint end is difficult to adjust, the GL15 wind brace can be loosened and then adjusted, so as to reserve adjustment means for subsequent adverse situations.

[0050] Positioning of short joints and matching holes of connecting plates: Cutting and drilling of short joint I-beams are carried out according to the design. The short joints on the south bank are pre-welded on the N5 plate. The short joints on the north bank are not installed yet and can be hoisted with the arch ribs. After the GL15 on the north bank is installed and the linear shape is adjusted, the reaction seats are welded on the chords at both ends of the joint mouth in advance, and the hand chain hoists are hung crosswise. They are gradually tightened at the joint temperature, and the arch ribs are temporarily locked. Then they are positioned and welded on the N5 plate. The elevation and axis of the short joint on the south bank must be kept in smooth connection. The filling welding can be carried out during the day. Note that the hand chain hoists need to be completely released during the day to avoid breaking during the daytime temperature rise.

[0051] After positioning, recheck and calculate whether the length of the connecting plate of the joint meets the actual needs. If not, cut it on the arch in time and mark the position of the hole of the connecting plate.

[0052] Locking of the joint mouth and unloading of the covering plate: Continuously observe the temperature and linear change patterns the next night. When the temperature is the same as that when the holes are matched and the linear shape is close to the theoretical linear shape, gradually tighten the hand chain hoist to temporarily lock the arch ribs and quickly tighten the high bolts. Complete the tightening of all high bolts at a constant temperature and complete the tightening of the GL15 wind brace high bolts during the day.

[0053] When the joint is at the closure temperature, measure the actual size of the closure mouth and proceed simultaneously with the cutting of the connecting plate to determine the size of the upper and lower chord tube docking sleeves, cut, install and weld, and complete the welding of the arch rib cover plate.

[0054] Closure construction resource allocation and implementation effect

[0055] One of the keys to instant closure is to allocate materials, machines, labor and other resources in sufficient quantities according to the progress of the implementation to ensure smooth closure. In terms of materials, sufficient steel plates, steel pipes, high-strength bolts and welding rods can be prepared according to the design drawings. The closure joint patch section is cut about 0.5m more, and the length is cut according to the measured length after the closure is locked. The connecting plate is cut according to the above estimate; in terms of equipment, it is necessary to meet the equipment required for the processes of short joint welding, connecting plate and patch section cutting, locking bolt tightening, closure port fine-tuning, etc., as shown in Table 2; in terms of labor, according to the simultaneous construction configuration of 8 closure work points, it is considered that the reserve personnel can be appropriately over-allocated, as shown in Table 3.

[0056] Table 2 Statistics of major large machinery and equipment

[0057]

[0058] Table 3 Labor force allocation table

[0059]

[0060]

[0061] The above reasonable allocation of resources ensures that the closure construction can be carried out continuously on multiple working surfaces. With the sections on both sides already installed, it only takes 2 days to achieve instant locking of the closure joints of the main arch of the Wujiang Bridge. The closure temperature is 25°C, the elevation deviation of the entire arch is less than 2.5cm, the lateral deviation is less than 1.5cm, the alignment deviation of the 8 chords is less than 3mm, and the closure accuracy reaches the industry-leading level.

[0062] Through the above means and measures, the Wujiang Bridge on Deyu Expressway successfully achieved the locking of the main arch closure posture within 2 days. The closure efficiency is fast and the locking accuracy is high, which can provide a reference for the construction of similar closure structures.

[0063] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A built-in instant closure device for a large-span arch bridge, characterized in that: The invention comprises a first main chord tube (1), a butt sleeve (2) and a second main chord tube (3); a first quick connection device is arranged inside the connection port of the first main chord tube (1); a second quick connection device is arranged inside the connection port of the second main chord tube (3); the butt sleeve (2) is connected to the connection port of the second main chord tube (3) and the first main chord tube (1); and the first quick connection device is connected to the second quick connection device; The first quick connection device is connected to the second quick connection device by setting a connection device, and two ends of the connection device are respectively connected to two ends of the first quick connection device and the second quick connection device; The connection device is provided as a connection plate (4), and a plurality of bolt holes are provided at both ends of the connection plate (4). Bolt holes are provided at both ends of the first quick connection device and the second quick connection device, and bolts are provided to pass through the connection plate (4) and both ends of the first quick connection device and the second quick connection device for fixing. The first quick connection device comprises a plurality of first main chord tube inclined plates (6), first main chord tube side plates (7), first main chord tube inclined plate connection blocks (8), first main chord tube inclined plate merging connection plates (9) and first main chord tube pad plates (10), wherein the plurality of first main chord tube inclined plates (6) are arranged obliquely in the first main chord tube (1), the first main chord tube inclined plates (6) are arranged at intervals with each other, the plurality of first main chord tube inclined plates (6) form a conical structure, and the first main chord tube inclined plate connection blocks (8) are arranged between the plurality of first main chord tube inclined plates (6) to form a conical structure. On the inner side of the conical top, a first main chord tube inclined plate connecting block (8) connects a plurality of first main chord tube inclined plates (6) into one body, a first main chord tube inclined plate merging connecting plate (9) is arranged at the ends of a plurality of first main chord tube inclined plates (6) and is connected to all the first main chord tube inclined plates (6), a first main chord tube pad (10) is arranged at the outer end of the first main chord tube inclined plate merging connecting plate (9), and a first main chord tube side plate (7) is arranged on both sides of the first main chord tube pad (10) and is respectively connected to the first main chord tube pad (10) and the first main chord tube inclined plate merging connecting plate (9); The second quick connection device comprises a plurality of second main chord tube inclined plates (12), a second main chord tube side plate (11), a second main chord tube inclined plate connection block (13), a second main chord tube inclined plate merging connection plate (14) and a second main chord tube pad plate (15), wherein the plurality of second main chord tube inclined plates (12) are arranged obliquely in the second main chord tube (3), the second main chord tube inclined plates (12) are arranged at intervals with each other, the plurality of second main chord tube inclined plates (12) form a conical structure, and the second main chord tube inclined plate connection block (13) is arranged between the plurality of second main chord tube inclined plates (12) forming a conical structure. On the inner side of the conical top, a second main chord tube inclined plate connecting block (13) connects a plurality of second main chord tube inclined plates (12) into one body, a second main chord tube inclined plate merging connecting plate (14) is arranged at the ends of a plurality of second main chord tube inclined plates (12) and is connected to all the second main chord tube inclined plates (12), a second main chord tube pad (15) is arranged at the outer end of the second main chord tube inclined plate merging connecting plate (14), and a second main chord tube side plate (11) is arranged on both sides of the second main chord tube pad (15) and is respectively connected to the second main chord tube pad (15) and the second main chord tube inclined plate merging connecting plate (14); The second main chord pipe pad (15) and the first main chord pipe pad (10) are both pre-arranged with a plurality of bolt holes, and the connecting plate (4) is provided with a plurality of connecting holes, the bolt holes at both ends of the connecting plate (4) correspond one to one with the bolt holes on the second main chord pipe pad (15) and the first main chord pipe pad (10), and bolts are arranged to pass through and be fixed; The specific process of closure is as follows: Cutting of the connection plate of the joint: According to the design requirements, the connection plate of the joint needs to be cut according to the measured length. The connection plate can be processed and cut after both sides are installed, and it is hoisted separately to the joint port of each chord for installation, which squeezes the joint time and is not conducive to the realization of instantaneous joint. According to the measured linear shape of the installed segment combined with the construction simulation analysis of the finite element software, the cutting length of the connection plate is predicted, and it is hoisted when the last segment is hoisted, saving the joint construction time. The specific process of the connection plate of the inner upper chord joint is as follows: the cutting calculation process is to use Midas The Civil finite element software analyzes the construction phase of the arch rib hoisting based on the optimization calculation method of one-time tensioning construction. Considering the tangential displacement, the difference in mileage of the ports of the upper chord pipes on the left and right sides of the two banks is calculated. The measured mileage of the ports on one bank is superimposed on the simulated mileage difference to obtain the estimated mileage of the ports on the other bank. The measured mileage of the ports on both banks is subtracted to obtain the length of the embedded section of the joint section. According to the joint structure design drawing, the embedded section is longer than the connecting plate, so the length of the proposed material is obtained by subtracting the length of the connecting plate. Since only the other bank is not installed and there is 80mm reserved space on both sides of the connecting plate, the calculated deformation of the other bank calculated by the construction simulation has a fixed error with the actual deformation, which can still meet the construction material cutting needs. Considering that it is more reliable, 30-40mm more material is cut on the basis of the estimate; Determining the timing of closure: The main arch closure construction is carried out during the period of the day when the temperature is the lowest and most stable. It is necessary to continuously observe the temperature and linear changes in the early stage of closure. The best time for closure is determined by analyzing the changing rules of temperature and linearity. Temperature sensors are installed on the main arch chord tubes and the data is connected to the monitoring cloud platform to monitor the temperature changes of the main arch in real time. The measurement robot automatically searches for measurement control points and automatically saves measurement data to monitor the linear changes of the main arch around the clock. The above observation methods provide measured data support for the selection of the timing of closure. Linear shape fine-tuning: In order to improve the linear shape accuracy of the joint and reduce the relative linear shape deviation of the corresponding segments on both sides, the linear shape fine-tuning is carried out on the two segments installed last on both sides. For the side installed first, observe the temperature and linear shape change law of the arch ribs from 1:00 to 6:00 in the morning, draw temperature and linear shape curves, and fine-tune the absolute linear shape according to the theoretical linear shape at the joint temperature. Then install the other side, and fine-tune the linear shape based on the relative deviation of the two sides. The relative deviation is controlled within 5mm, and then install the wind brace. The installation process on both sides is the same, but the relative deviation of the later installation side needs to be controlled within 2mm. After the later installed wind brace is installed in place, only punch nails and ordinary bolts for temporary fixing are installed. High-strength bolts are installed after the joint is closed. If the subsequent joint end is difficult to adjust, the wind brace is released before adjustment, so as to reserve adjustment means for subsequent adverse situations. Positioning of short joints and matching holes of connecting plates: Cutting and drilling of I-beams of short joints are carried out according to the design. The short joints of the south bank are pre-welded on the connecting plate of the inclined plate. The short joints of the north bank are not installed for the time being and are hoisted first with the arch ribs. After the north bank is installed in place and the linear shape is adjusted, the reaction seats are welded on the chords at both ends of the joint mouth in advance, and the hand chain hoists are hung crosswise. When the joint temperature is reached, they are gradually tightened to temporarily lock the arch ribs, and then positioned and welded on the connecting plate of the inclined plate. The elevation and axis of the short joints of the south bank must be kept in smooth connection. The filling welding can be carried out during the day. The hand chain hoists need to be completely released during the day to avoid breaking during the daytime temperature rise. After positioning, recheck and calculate whether the length of the joint connection plate meets the actual needs. If not, cut it on the arch in time and mark the position of the connection plate holes; Locking of the closure and unloading of the cladding: Continuously observe the temperature and linear change patterns the next night. When the temperature is the same as that during the hole matching and the linear shape is close to the theoretical linear shape, gradually tighten the hand chain hoist to temporarily lock the arch ribs and quickly tighten the high bolts. At a constant temperature, complete the tightening of all high bolts, and complete the tightening of wind brace high bolts during the day; When the joint is at the closure temperature, measure the actual size of the closure mouth and proceed simultaneously with the cutting of the connecting plate to determine the size of the upper and lower chord tube docking sleeves, cut, install and weld, and complete the welding of the arch rib cover plate.

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