Bridge demolition and reconstruction treatment process under traffic keeping condition

Abstract

The invention relates to the technical field of bridge construction, in particular to a bridge demolition and reconstruction treatment process under the unobstructed condition, which comprises the steps that two roads below a bridge main span are divided into a first half range and a second half range, the main span above the first half range is a first main span, and the main span above the second half range is a second main span; the first half part is communicated and the second half part is enclosed; the surface layer of the second main span is crushed, and the crushed surface layer is transferred; a hollow temporary supporting frame is assembled on the second half range, concrete is poured into the temporary supporting frame, and after the concrete is solidified, a jack is arranged between the temporary supporting frame and the second main span and abuts against the temporary supporting frame; the second main span is cut off, and the second main span is hoisted to a beam storage site through a crane after being cut off; the jack is unloaded, and the temporary supporting frame is continuously hoisted to the beam storage site through the crane; according to the construction method, the construction difficulty of bridge demolition and reconstruction under the traffic keeping condition can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, in particular to a process for dismantling and rebuilding a bridge under the condition of ensuring traffic flow. Background Art

[0002] When a bridge is structurally aged, has insufficient functions, or has outdated design standards, it often needs to be demolished and rebuilt. During the process of dismantling and rebuilding the bridge, it is necessary to consider traffic flow and reduce obstacles to the original traffic routes. The traffic routes mentioned here include not only the traffic routes where the bridge is located, but also the traffic routes below it. Figure 1 As shown, when a bridge includes a main span and a side span, two lanes traveling in opposite directions often cross under the main span of the bridge.

[0003] In the prior art, two methods are usually considered when maintaining traffic routes under the main span of a bridge. The first method is to build a new access road outside the original route, and then demolish the access road after the bridge is demolished and rebuilt. The second method is to carry out half-demolition and half-reconstruction on the original route, so as to always keep one of the lanes available to ensure traffic. Since the second method has lower costs and a shorter construction period, the half-demolition and half-reconstruction method is currently used more often.

[0004] For example, a method for rapid bridge demolition under traffic-protection conditions disclosed in publication number CN118653391A adopts the above-mentioned second traffic-protection means, including the following steps: S1, determine the location of the beam storage site; S2, temporarily close the second half of the space, and keep the first half of the space in an open traffic state; S3, mark and confirm the construction points respectively; S4, install a temporary bracket on one side of the pier in the second half of the space under the bridge to be demolished, and use the temporary bracket to support the bottom of the bridge to be demolished; S5, cut off the bridge to be demolished through the first incision and the second incision; S6, move the modular beam transporter to the lower part of the main span structure, and then support the main span structure through the unloading block; S7, release the stress state of the support on the pier under the main span structure; S8, transport the main span structure to the beam storage site and place it on the beam drop frame in the beam storage site. In short, the main span demolition process under traffic-protection conditions includes three main steps: temporary support, cutting and lifting.

[0005] However, the following deficiencies are still found in the process of construction using the above construction methods. First, since the bridge is heavy after being cut, a crane with strong lifting capacity is required for lifting, which undoubtedly increases the selection requirements of the crane; second, the support frame is usually prefabricated and then transported to the site for assembly. In order to ensure the supporting capacity of the temporary support frame, the strength of the temporary support frame needs to be improved, which also leads to the temporary support frame being heavy, inconvenient to transport and difficult to assemble on site. Therefore, in order to further reduce the construction difficulty of dismantling and rebuilding the bridge under the condition of maintaining traffic, thereby reducing the probability of safety accidents, the above deficiencies in the existing technology need to be solved urgently. Summary of the invention

[0006] In order to reduce the difficulty of transporting and assembling the temporary support frame on site while lowering the requirements for the selection of cranes, the present application provides a bridge demolition and reconstruction process under the condition of ensuring traffic.

[0007] The present invention provides a bridge demolition and reconstruction process under the condition of maintaining traffic, which adopts the following technical solutions:

[0008] A process for dismantling and rebuilding a bridge under the condition of maintaining accessibility, comprising the following steps: dividing two roads below the main span of the bridge into a first half and a second half, the main span above the first half being the first main span, and the main span above the second half being the second main span; maintaining accessibility for the first half, and providing enclosure for the second half; crushing the surface layer of the second main span and transferring the crushed surface layer; assembling a hollow temporary support frame on the second half, and pouring concrete into the temporary support frame, and after the concrete solidifies, setting a jack between the temporary support frame and the second main span and tightening it; cutting off the second main span, and after cutting off, hoisting the second main span to a beam storage site by a crane; removing the jack, and continuing to use the crane to hoist the temporary support frame to the beam storage site; providing enclosure for the first half, maintaining accessibility for the second half, and repeating the above steps to dismantle the first main span.

[0009] Preferably, a crushing area is defined in the second half width, a crusher is arranged in the crushing area, and the crushed surface layer is crushed by the crusher and then subjected to CO 2 After mineralization treatment, recycled aggregate is generated.

[0010] Preferably, the concrete poured into the temporary support frame contains the recycled aggregate formed by the surface layer.

[0011] Preferably, the cutting slit formed by cutting is U-shaped, and the notch of the cutting slit faces outwards.

[0012] Preferably, when the first main span and the second main span are lifted, they are first lifted by the jack, and after being lifted, an overlapping area is retained between the two opposite cut surfaces of the cutting seam; the cutting seams of the first main span and the second main span respectively form four bull horns, and after being lifted, the first main span and the second main span are both provided with lifting rings at the bull horns, and then the crane lifts the first main span and the second main span through the lifting rings.

[0013] Preferably, the cutting seam is located at a position 1 / 5 of the span from the center line of the pier to avoid the peak bending moment area.

[0014] Preferably, when the surface layers of the first main span and the second main span are crushed, the surface layers at the positions to be cut are crushed first.

[0015] Preferably, the temporary support frame is prefabricated in modules, and after prefabrication, it is transported to the site for assembly.

[0016] Preferably, the first main span and the second main span are cut by a cutting machine, the cutting machine adopts a diamond wire saw, and the cutting machine is located outside the area to be cut.

[0017] Preferably, the first half and the second half are both set up with two-way lanes when maintaining traffic, and the occupancy status of each lane in the maintenance area is identified in real time by an AI camera, and the traffic density is monitored in combination with a geomagnetic sensor, and the lane marking position and signal light timing are dynamically adjusted; the lane and traffic data are connected to the navigation platform to induce vehicle diversion in advance.

[0018] The beneficial effects of the present invention are:

[0019] 1. First, no matter it is the first main span or the second main span, it is cut and hoisted after its surface layer is removed. After the surface layer is removed, the weight of the first main span or the second main span during hoisting can be effectively reduced, thereby reducing the requirements for the selection of cranes; secondly, since the temporary support frame is a hollow structure before pouring concrete, the structure of the temporary support frame is lighter, which reduces the difficulty in transportation or ready-made assembly. Finally, the present invention further reduces the construction difficulty of bridge dismantling and reconstruction under the condition of maintaining traffic, thereby effectively reducing the probability of safety accidents;

[0020] 2. The concrete poured inside the temporary support frame uses recycled aggregate formed by the surface layer, which effectively achieves the effect of recycling and reusing the demolished structure of the bridge surface layer, has a green and environmentally friendly effect, and reduces the demolition cost;

[0021] 3. Since the cutting seam is U-shaped, the four corners of the main span after cutting off form bull horns. The main span after jacking up is easy to open and insert the lifting ring at its bull horns, thereby improving the lifting convenience of the main span after cutting off. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the main span and side span of the bridge in the background technology when it is open to traffic;

[0023] Figure 2 It is a structural schematic diagram of the main span and the side span of the bridge in the embodiment of the present application when they are demolished;

[0024] Figure 3 This is a top view of the second main span after being cut off in the embodiment of the present application.

[0025] Explanation of the accompanying reference numerals: 11, first half; 12, second half; 21, first main span; 22, second main span; 3, surface layer; 4, temporary support frame; 5, jack; 6, cutting seam. DETAILED DESCRIPTION

[0026] The following will be combined Figure 2 and Figure 3 The present invention is further illustrated by the following embodiments.

[0027] This embodiment discloses a process for dismantling and rebuilding a bridge under conditions of ensuring traffic flow.

[0028] Reference Figure 2 and Figure 3 The bridge demolition and reconstruction process under the condition of maintaining traffic conditions includes the following steps:

[0029] S1: The two roads under the main span of the bridge are divided into the first half 11 and the second half 12. The first half 11 is open to traffic, and the second half 12 is enclosed. Correspondingly, the main span above the first half 11 is the first main span 21, and the main span above the second half 12 is the second main span 22. Whether it is the first half 11 or the second half 12, two-way lanes are provided in the case of openness, and the ratio between the two-way lanes is adjusted according to the morning and evening peak traffic flow to reduce traffic impact. In order to accurately adjust the ratio between the two-way lanes, the occupancy of each lane in the open area is identified in real time by an AI camera, and the traffic density is monitored in combination with a geomagnetic sensor, and the lane marking position and signal light timing are dynamically adjusted to achieve dynamic intelligent traffic control. In addition, lane and traffic data are connected to navigation platforms such as Amap, Baidu, Google Maps, etc., to induce vehicle diversion in advance.

[0030] S2: Use an excavator equipped with a breaker hammer or bucket to first crush the surface layer 3 of the second main span 22, and give priority to crushing the surface layer 3 at the to-be-cut positions on the left and right sides of the second main span 22, so as to mark the cutting route after breaking, speed up construction efficiency, and shorten the construction period. It is also possible to consider carrying out cutting work simultaneously when breaking the remaining surface layer 3, so as to further shorten the construction period. In this embodiment, the crushed surface layer 3 includes a bridge deck pavement layer, a waterproof layer, a leveling layer, and a protective layer. The surface layer 3 of the main span is broken and then hoisted, which can effectively reduce the weight of the main span during hoisting, thereby reducing the requirements for the selection of the crane.

[0031] S3: A crushing area is defined in the second half width 12, a crusher is set in the crushing area, and then the surface layer 3 crushed in the second main span 22 is transferred to the crushing area of ​​the second half width 12 and crushed by the crusher, and then the surface layer 3 crushed in the second main span 22 is crushed by the crusher. 2 After the mineralization treatment, the recycled aggregate is generated. The surface layer 3 is crushed and then subjected to the mineralization treatment, which can not only increase the reaction speed but also improve the fineness of the recycled aggregate.

[0032] S4: Assemble at least two temporary support frames 4 in the second half 12. In this embodiment, the number of temporary support frames 4 in each half is two. The temporary support frames 4 are hollow inside and poured with concrete. The concrete uses the recycled aggregate in S3. On the one hand, the hollow interior of the temporary support frame 4 means that the structure of the temporary support is lighter, which is convenient for transportation and on-site assembly. On the other hand, it effectively achieves the effect of recycling and reusing the dismantled structure of the bridge surface layer 3, has a green and environmentally friendly effect, and reduces the demolition cost. There are two ways to assemble the temporary support frame 4. The first is to prefabricate in modules, then transport them to the site for assembly, and then pour concrete after assembly. The second is to directly set up on site using external formwork, and then pour concrete after the erection is completed.

[0033] S5: After the concrete in the temporary support frame 4 solidifies, a jack 5 is set between the temporary support frame 4 and the second main span 22 and tightened. In this embodiment, there are multiple support points between the top of the temporary support frame 4 and the main span, and the number of jacks 5 is set corresponding to the number of support points, thereby achieving multi-point support and improving the effect of temporary support. In addition, the jack 5 is installed with an adaptive hydraulic support system with pressure feedback and fine-tuning functions, so as to facilitate adaptive adjustment according to its support condition for the main span.

[0034] S6: The second main span 22 is cut synchronously on the left and right sides of the second main span 22 by a cutting machine to form a cutting seam 6. The cutting machine uses a diamond wire saw for cutting. Thus, the second main span 22 is cut off. In this embodiment, the cutting machine is located outside the area to be cut off, so that after cutting, the cut main span can be lifted more quickly by a crane without waiting for the transfer of the cutting machine. The center position of the cutting seam 6 is set at 1 / 5 of the span from the center line of the pier to avoid the peak bending moment area, so as to avoid the second main span 22 from being easily disconnected by itself during the cutting process, and finally improve the safety factor. Furthermore, the cutting seam 6 formed by cutting is U-shaped, and the notch of the cutting seam 6 faces outward. The U-shaped cutting seam 6 can horizontally limit the main span after cutting, thereby improving the position stability of the main span after cutting.

[0035] S7: Use the jack 5 to lift up the cut second main span 22. After lifting up, the overlap area is retained between the two opposite cut surfaces of the cutting seam, thereby limiting the lifting height and ensuring that the overlap between the cut surfaces can limit the horizontal position of the second main span 22. First, use a crane to lift the cut second main span 22 to the beam storage site. After removing the jack 5, use the same crane to lift the temporary support frame 4 to the beam storage site. Finally, the second main span 22 and the temporary support frame 4 are dismantled and recovered at the beam storage site, so that there is no need to break the temporary support frame 4 in the second half 12, which is convenient for quickly removing the enclosure of the second half 12, so as to quickly restore the traffic state. It should be noted that since the cutting seam 6 is U-shaped, the four corners of the cut main span form horns, and the main span after lifting up is easy to open and insert the lifting ring at its horns, thereby improving the convenience of lifting the cut main span.

[0036] S8: Adjust the first half span 11 to block and the second half span 12 to ensure access, repeat the steps of S1-S7, and dismantle the first main span 21.

[0037] S9: The remaining structure of the bridge outside the first half span 11 and the second half span 12 is demolished on site.

[0038] S10: Rebuilding the bridge, wherein the main beam of the main span is pushed into place by a pushing mechanism to avoid obstruction to the two roads below it. In other embodiments, other means of ensuring traffic flow may also be used to rebuild the bridge, thereby reducing traffic obstruction below it during the reconstruction process.

[0039] The implementation principle of the bridge dismantling and reconstruction process under the condition of maintaining traffic in this embodiment is as follows: first, whether it is the first main span or the second main span, it is cut and hoisted after the surface layer is removed. After the surface layer is removed, the weight of the first main span or the second main span during hoisting can be effectively reduced, thereby reducing the requirements for the selection of cranes; secondly, since the temporary support frame is a hollow structure before pouring concrete, the structure of the temporary support frame is relatively light, which reduces the difficulty during transportation or on-site assembly. Finally, the present invention further reduces the construction difficulty of bridge dismantling and reconstruction under the condition of maintaining traffic, thereby effectively reducing the probability of safety accidents.

[0040] The above are all preferred embodiments of the present invention, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A bridge demolition and reconstruction process under the condition of maintaining traffic, characterized in that: The following steps are involved: The two roads below the main span of the bridge are divided into a first half (11) and a second half (12); the main span above the first half (11) is the first main span (21), and the main span above the second half (12) is the second main span (22); the first half (11) is kept open, and the second half (12) is enclosed; the surface layer (3) of the second main span (22) is crushed and the crushed surface layer (3) is transferred; a hollow temporary support frame (4) is assembled on the second half (12), and the temporary support frame (4) is moved to the second half (12); ) and after the concrete solidifies, a jack (5) is arranged between the temporary support frame (4) and the second main span (22) and tightened; the second main span (22) is cut off and after cutting, the second main span (22) is hoisted to a beam storage site by a crane; the jack (5) is removed and the temporary support frame (4) is hoisted to a beam storage site by the crane; the first half (11) is enclosed and the second half (12) is kept open, and the above steps are repeated to dismantle the first main span (21).

2. The process for dismantling and rebuilding a bridge under the condition of maintaining traffic according to claim 1 is characterized by: A crushing area is defined in the second half width (12), and a crusher is arranged in the crushing area. The crushed surface layer (3) is crushed by the crusher and then subjected to CO2 mineralization treatment to generate recycled aggregate.

3. The process for dismantling and rebuilding a bridge under the condition of maintaining traffic according to claim 2 is characterized by: The concrete poured into the temporary support frame (4) contains the recycled aggregate formed by the surface layer (3).

4. The process for dismantling and rebuilding a bridge under traffic-maintaining conditions according to claim 1 is characterized in that: The cutting slit (6) formed by cutting is U-shaped, and the notch of the cutting slit (6) faces outwards.

5. The process for dismantling and rebuilding a bridge under the condition of maintaining traffic according to claim 4 is characterized by: When the first main span (21) and the second main span (22) are hoisted, they are first lifted up by the jack (5). After being lifted up, an overlapping area is retained between two opposite cut surfaces of the cutting seam (6). The cutting seams (6) of the first main span (21) and the second main span (22) are respectively formed with four horns. After being lifted up, the first main span (21) and the second main span (22) are both provided with lifting rings at the horns. Then, the crane lifts the first main span (21) and the second main span (22) through the lifting rings.

6. The process for dismantling and rebuilding a bridge under the condition of maintaining traffic according to claim 4 is characterized by: The center position of the cutting seam (6) is set at 1 / 5 of the span from the center line of the pier, avoiding the bending moment peak area.

7. The process for dismantling and rebuilding a bridge under traffic-maintaining conditions according to claim 1 is characterized by: When crushing the surface layers (3) of the first main span (21) and the second main span (22), the surface layers (3) at the positions to be cut are crushed first.

8. The process for dismantling and rebuilding a bridge under traffic-maintaining conditions according to claim 1 is characterized by: The temporary support frame (4) is prefabricated in modules and then transported to the site for assembly after prefabrication.

9. The process for dismantling and rebuilding a bridge under traffic-maintaining conditions according to claim 1 is characterized by: The first main span (21) and the second main span (22) are cut by using a cutting machine, wherein the cutting machine is a diamond wire saw and the cutting machine is located outside the area to be cut.

10. The process for dismantling and rebuilding a bridge under traffic-maintaining conditions according to claim 1, characterized in that: The first half (11) and the second half (12) are both set up as two-way lanes when maintaining traffic flow. The AI ​​camera is used to identify the occupancy status of each lane in the maintenance area in real time, and the traffic density is monitored in combination with the geomagnetic sensor to dynamically adjust the lane marking position and signal light timing; the lane and traffic flow data are connected to the navigation platform to induce vehicle diversion in advance.

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