A structure for preventing overturning of a bridge with a column-type pier

Abstract

The present application relates to the technical field of civil engineering, and specifically relates to a toughened column pier bridge anti-overturning structure, which comprises a steel structure connected to the position close to the beam body on the upper part of the bridge pier through high-strength anchor bolts, is used for realizing lateral bridge pier expansion connection, and pours steel fiber reinforced concrete in the space between the steel structure and the high-strength anchor bolts; lateral prestressed tendons are arranged at the position close to the beam body on the upper part of the bridge pier and support the steel structure, exert lateral pre-pressure on the bridge pier and its connecting structure, and make the original upper section of the bridge pier be in vertical and lateral compression state; vertical supports are arranged on the lateral sides of the steel structure and are located at the position close to the main girder on the upper part of the bridge pier, and a spacing is left between the top surface of the vertical support and the bottom surface of the beam body, and the advantage of the present application lies in that the anti-overturning capacity of the whole bridge is improved under the requirement of slight deformation of the bridge under the normal driving state of the vehicle, and the limit state can be prewarned.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of civil engineering, in particular to a toughened column pier bridge anti-overturning structure. BACKGROUND

[0002] In recent years, single-column pier bridges with a single column and a single support in the middle of multi-span bridges have caused many serious accidents of bridge lateral overturning and overall collapse under extreme overload trucks. At present, there are many technical solutions to improve the anti-overturning performance of the above bridges.

[0003] In the invention patent "A single-column pier bridge anti-overturning drop beam device" (CN 111945548 A), a scheme is designed to connect the upper structure and the lower structure through anchoring brackets and compression springs on the side of the pier cap beam and the side of the main beam, forming a force whole.

[0004] In the invention patent "A bridge anti-overturning device and its construction method" (CN 114747467 A), it is proposed to use anchor bolts and tension-resistant components to connect the cap beam and the main beam to improve the anti-overturning stability of the bridge.

[0005] In the invention patent "A viaduct anti-overturning and dumping alarm system" (CN 114990988 A), it is proposed to use a combination of sliding components, hydraulic devices, and damping balls to slow down the overturning process of the upper structure and alert personnel when the bridge overturns.

[0006] In the invention patent "A single-column pier bridge anti-overturning energy dissipation reinforcement device" (CN 111877189 A), a ring-shaped hoop assembly is used to achieve fixed connection of the device with the pier and the beam body, and the lateral displacement of the bridge under earthquakes and heavy vehicles is dissipated through the deformation of the connecting device.

[0007] In the invention patent "A steel structure for column pier bridge canopy jacking without interrupting traffic" (CN 215329416 U), a steel hoop, a steel corbel, a high-strength anchor bolt, and a grouting layer are used to form an extended steel corbel on the existing pier, and in addition to replacing the support construction, auxiliary supports can also be placed to assist in anti-overturning.

[0008] In the invention patent "A single-column pier bridge anti-overturning reinforcement device" (CN 214219419 U), the bridge beam body, support, and pier are welded in a full-welding manner, and the cap beam is connected to the pile cap to improve the overturning stability.

[0009] In the invention patent "A single-column pier bridge anti-overturning reinforcement device" (CN 216445821 U), a truss form is used to add a new support structure on the existing pier to improve the anti-overturning stability of the bridge.

[0010] From the currently disclosed design scheme, the reinforcement measures for the main girder overturning do not involve several key contents: 1. The bridge structure is designed according to the requirements of the specification, and has a design allowable lateral deformation under the action of normal vehicle load, but the reinforcement scheme currently adopted is a fixed mode, which will cause the reinforced structure to be additionally constrained and unable to produce the design allowable free deformation under the action of normal vehicle load; 2. This fixed mode essentially changes the entire bridge stress structure system, and the constrained deformation under the action of normal vehicle load will in turn generate additional forces and moments on the bridge pier that are not considered in the original bridge design, but the disclosed scheme does not reinforce the lower part of the bridge pier which is the weakest in stress, which will cause the originally safe bridge pier under the action of normal vehicle load to be damaged after reinforcement; 3. The existing reinforcement mode still relies on the load bearing capacity of the girder body and the load bearing capacity of the bridge pier in the original bridge design for the final overturning safety of the structure, and will not greatly improve the anti-overturning bearing capacity of the bridge, and there is still a risk of overturning under extreme vehicle action. SUMMARY

[0011] The present application provides a kind of toughening column pier bridge anti-overturning structure, guarantee the slight deformation under normal vehicle driving state, improve the anti-overturning ability of whole structure, and carry out remote early warning to extreme event.

[0012] In order to achieve the above purpose, a kind of toughening column pier bridge anti-overturning structure is designed, including steel structure, which is connected to the position near girder body on the upper part of bridge pier by high-strength anchor bolt, for realizing lateral bridge pier expansion connection, and pouring steel fiber reinforced concrete in the space between steel structure and high-strength anchor bolt;Lateral prestressed tendon is arranged at the position near girder body on the upper part of bridge pier, and supports the steel structure, and applies lateral pre-pressure to bridge pier and its connecting structure, so that the original upper section of bridge pier is in vertical and lateral compression state;Vertical support is arranged on the lateral sides of steel structure and located at the position near main girder on the upper part of bridge pier, and the top surface of vertical support and the bottom surface of girder body are left with a spacing ΔL1, ΔL1 satisfies ΔL1=α max ×d1+1-3mm;Vertical pull rod is located in the vertical direction close to bridge pier, vertical pull rod passes through beam bottom, is anchored in girder body on one side, is fixed with steel structure on the other side, and the anchoring position and the top surface of beam bottom are left with a spacing ΔL2, ΔL2 satisfies ΔL2=α max ×d2+1-3mm;α max It is the maximum allowable torsion angle under design load, d1 is the spacing from vertical support to bridge pier center, and d2 is the spacing from vertical pull rod anchoring position to bridge pier center.

[0013] The present application also has the following preferred technical solutions:

[0014] 1. Steel fiber concrete pouring before, vertical pull rod through the steel structure and pier, the upper end through the concrete beam bottom hole into the beam body, pouring steel fiber concrete, vertical pull rod and steel fiber concrete between the formation of the gripping force.

[0015] 2. Pouring steel fiber concrete and solidification, tension transverse prestressed tendon, the upper part of the pier under the action of beam body self weight and transverse prestress, form a two-way compression state, increase the bearing capacity of the ultimate load; transverse prestressed tendon in steel structure and steel fiber concrete form transverse pressure, for steel fiber concrete to form pre pressure.

[0016] 3. The lower part of the pier near the ground is reinforced with carbon fiber, increasing the bearing capacity of the lower part of the pier under the action of eccentric load in the ultimate state.

[0017] 4. Steel structure includes: upper transverse prestressed anchorage steel structure and lower transverse prestressed anchorage steel structure, for transverse prestressed tendon and anchorage; vertical support anchorage steel structure, for vertical support and lower anchorage; bottom steel structure and side steel structure, forming the outer wrapping, providing the outermost constraint for the pouring of steel fiber concrete; stiffened steel structure, as the connecting force component of the whole steel structure and steel fiber concrete.

[0018] 5. Including alarm components for achieving alarm under the design load, alarm components include upper metal sheet, lower metal sheet, micro power generation device, current acquisition device and signal sending device, vertical support top surface is provided with lower metal sheet, the bottom surface of the beam body is provided with lower metal sheet at the opposite position, one end of the lower metal sheet is connected with the micro power generation device, the other end is connected with the current acquisition device and the signal sending device, the upper metal sheet is connected with the current acquisition device and the signal sending device, when the upper metal sheet and the lower metal sheet contact, the current acquisition device receives the current of the micro power generation device, and the signal sending device transmits the alarm signal; under normal load state, the beam body and the vertical support do not contact, the upper metal sheet and the lower metal sheet are separated to disconnect the whole circuit and do not produce any signal; under the action of extreme load, the beam body and the vertical support contact, the upper metal sheet and the lower metal sheet are attached, so that the circuit is connected, the micro power generation device generates a small current, the current acquisition device collects the current signal, sends the signal to the signal sending device, and the signal sending device transmits the signal to the remote control center, so as to realize the alarm of the extreme condition.

[0019] Compared with the prior art, the application has the advantages that the overall anti-overturning capacity of the bridge is improved under the requirement of slight deformation of the bridge under the normal driving state of the vehicle, and the limit state can be warned in advance. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The figure is a schematic diagram of the overall structure of the application;

[0021] Figure 2 Schematic diagram of the size code designed for the present application;

[0022] Figure 3 Schematic diagram of the alarm component of the present application;

[0023] Figure 4 Schematic diagram of the rigid support platform of the present application;

[0024] In the figure: 1. Ground, 2. Beam body, 3. Pier, 4. Support, 5. Rigid support platform, 6. Anchor bolt, 7. Steel fiber concrete, 8. Transverse prestressed tendon, 9. Vertical support, 10. Vertical pull rod, 11. Carbon fiber structure, 12. Alarm component, 121. Upper metal sheet, 122. Lower metal sheet, 123. Current collection device, 124. Sending device, 125. Micro power generation device, 126. Wire, 501. Upper transverse prestressed anchoring steel structure, 502. Lower transverse prestressed anchoring steel structure, 503. Vertical support anchoring steel structure, 504. Bottom steel structure, 505. Side steel structure; 506. Reinforced steel structure. DETAILED DESCRIPTION

[0025] The structure and principles of the present application will be further described below in conjunction with the accompanying drawings, which are very clear to those skilled in the art. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0026] The present application is a kind of toughened column pier bridge anti-overturning structure, the specific structure is as follows:

[0027] 1. The upper part of the pier is close to the position of the beam body, which realizes the transverse pier expansion connection through the special designed steel structure, high-strength anchor bolt and steel fiber concrete.

[0028] 2. The upper part of the pier is close to the position of the beam body, in addition to the expansion connection, the transverse prestressed tension is used to apply transverse pre-pressure to the pier and its connecting structure, so that the original upper section of the pier is in vertical and transverse compression state, and the resistance of itself is increased; at the same time, the transverse prestress increases the adhesion of steel structure, steel fiber concrete and existing pier.

[0029] 3. The upper part of the pier is close to the position of the main beam, in addition to the expansion connection, vertical support is designed on the top surface of the steel structure, and a certain gap Δ is left between the top surface of the vertical support and the bottom surface of the beam body. L 1. The maximum allowable torsion angle α of the bridge under design load max The corresponding transverse distance is d 1. The deformation of the position can occur freely, and the design size relationship meets the following requirements:

[0030] Δ L 1=α max ×d 1+1-3mm.

[0031] 4、preferably, the increased ultimate state vertical support to the transverse distance to the pier beam center d 1 should not be less than 1.25m, the parameter is determined by statistical analysis data, in the case of sufficient bearing capacity of the bridge pier, not less than 1.25m center distance of ultimate state vertical support has significant improvement on the overall stability of the bridge overturning.

[0032] 5, the upper part of the pier near the main beam, in addition to the expansion of the connection and the ultimate state vertical support, in the vertical direction close to the pier, through the vertical pull rod through the beam bottom, anchoring in the beam, the other side of the additional steel fiber reinforced concrete, fixed with the rigid support platform. The anchoring position in the beam is kept a certain distance Δ from the beam bottom surface L 2, the maximum allowable torsion angle α of the bridge under the design load max The corresponding transverse distance d 2 position can occur freely, the design size relationship meets the following requirements:

[0033] Δ L 2=α max × d 2+1-3mm.

[0034] 6, above, through the ultimate state vertical support with a distance Δ L 1 and the ultimate state vertical pull rod with a distance Δ L 2, the reinforcement structure does not change the bridge structure system under normal design load, so that the stress characteristics of the existing structure under normal load are still consistent with the design state, and the safety of the structure under normal state is ensured. Under the extreme vehicle action exceeding the design load, the ultimate state vertical support, the ultimate state vertical pull rod and the beam body and the lower structure are connected to form a new structure system, which forms a new resisting moment through one side tension and one side compression, and improves the anti-overturning stability of the bridge beam body part.

[0035] 7, in the extreme case exceeding the design load, due to the change of the structure system, the structure at the upper part of the pier close to the main beam position brings a large eccentric load to the section at the lower part of the pier close to the ground position, so that the section close to the ground position of the pier becomes the key to restrict the overall overturning stability of the structure. In particular, the ultimate bearing capacity of the section is improved by carbon fiber reinforcement, thereby improving the resistance of the entire pier in the overturning process.

[0036] 8, further, in order to realize the alarm of the above-mentioned pier reinforcement structure under the design load, a current collecting device, a signal sending device, a wire, a metal sheet and a micro power generation device are arranged outside the vertical support.

[0037] 9. One metal sheet is placed at the bottom of the beam and another at the top of the vertical support. These metal sheets are connected in series with other electrical devices. Under normal load conditions, the beam and vertical support do not contact each other; the two metal sheets separate, breaking the entire circuit and generating no signal. Under extreme loads, the beam and vertical support come into contact, and the two metal sheets adhere, connecting the circuit. The miniature generator produces a small current, which is collected by the current acquisition device and sent to the signal transmission device. The signal transmission device then transmits this signal to the remote control center, providing an alarm for extreme situations.

[0038] In one specific implementation method

[0039] See Figure 1 As shown, a specially designed steel structure is used at the upper part of the pier near the beam, and high-strength anchor bolts are inserted into the upper part of the existing pier to connect the existing pier. Steel fiber reinforced concrete is poured into the space between the pier, the specially designed steel structure and the high-strength anchor bolts to form a whole.

[0040] Before the steel fiber reinforced concrete is poured, the ultimate state vertical tie rod passes through the specially designed steel structure and the pier. The upper end is inserted into the beam through a hole drilled in the bottom of the concrete beam. After the steel fiber reinforced concrete is poured, a bond force is formed between the ultimate state vertical tie rod and the steel fiber reinforced concrete.

[0041] After the steel fiber reinforced concrete is poured and solidified, the transverse prestressing tendons are tensioned, causing the upper part of the existing pier to be under bidirectional compression under the combined action of the beam's self-weight and transverse prestressing. This improves the stress state of the upper section of the pier and increases its ability to withstand ultimate loads. At the same time, the tensioning of the prestressing tendons creates transverse pressure in the specially designed steel structure and steel fiber reinforced concrete, making the connection between them and the pier more robust and creating prestress for the steel fiber reinforced concrete, significantly improving the stress conditions of the concrete.

[0042] By reinforcing the lower part of the bridge pier near the ground with carbon fiber, the bearing capacity of the lower section of the pier under eccentric loads in the ultimate condition is increased. Through separate reinforcement measures on the upper and lower parts of the pier, the overall overturning resistance of the pier is improved.

[0043] Ultimate limit state vertical supports are installed on the top surface of the specially designed steel structure. The distance from the ultimate limit state vertical supports to the center of the beam and the pier is... d 1 (e.g.) Figure 2 As shown, the distance Δ between the top surface of the vertical support and the bottom of the beam in the ultimate condition is set to 1.25m. L 1. The maximum allowable torsional angle α of a bridge under design load. max Δ L 1=α max × d 1+2mm.

[0044] The anchoring of the ultimate state vertical tie rod through the steel fiber reinforced concrete and the beam bottom plate inside the beam leaves a distance Δ from the top surface of the beam bottom plate L 2, the distance from the center of the bridge is d 2, the maximum allowable torsion angle of the bridge under the design load is α max , Δ L 2=α max × d 2+2mm.

[0045] An alarm component is arranged outside the top surface of the specially designed steel structure and the ultimate state vertical support.

[0046] As shown in Figure 3 , the alarm component is composed of an upper metal sheet, a lower metal sheet, a current collection device, a signal sending device, and a micro power generation device, which are connected in series through wires.

[0047] Among them, the upper metal sheet is installed on the bottom surface of the beam bottom plate, and the lower metal sheet is installed on the top surface of the ultimate state vertical support. Both are in a non-contact state when the bridge is normally stressed, and the upper metal sheet and the lower metal sheet on the transverse side come into contact with each other when the torsion of the beam exceeds the design allowable value.

[0048] At this time, the micro power generation device is located between the beam bottom and the pier, and when the beam is twisted, the micro power generation device can generate a small current based on electromagnetic principles, mechanical principles, or piezoelectric principles.

[0049] When the bridge is normally stressed, the upper metal sheet and the lower metal sheet are not in contact, and the entire alarm component circuit is in a short-circuit state, and the electronic system does not work; when the torsion of the beam exceeds the design allowable value, the upper metal sheet and the lower metal sheet on the transverse side come into contact with each other, forming a loop, and the current collection device and the signal sending device receive the current generated by the micro power generation device, realizing signal transmission.

[0050] As shown in Figure 4 , an example of a special steel structure mentioned in this patent is shown.

[0051] The upper transverse prestressed anchoring steel structure and the lower transverse prestressed anchoring steel structure are used for transverse prestressed threading and anchoring, the ultimate state vertical support anchoring steel structure is used for ultimate state vertical support threading and lower anchoring, and the bottom steel structure and the side steel structure form an external wrapping, providing the outermost constraint for Figure 1 the pouring of the steel fiber reinforced concrete in the middle, and the stiffening steel structure is a component that strengthens the entire steel structure and Figure 1 connects the stressed components of the steel fiber reinforced concrete in the middle.

Claims

1. A toughened column-pier bridge anti-overturning structure, characterized in that... include The steel structure is connected to the upper part of the pier near the beam by high-strength anchor bolts to realize the lateral expansion connection of the pier, and steel fiber concrete is poured into the space between the steel structure and the high-strength anchor bolts. Transverse prestressing tendons are installed on the upper part of the pier near the beam, supporting the steel structure and applying transverse prestress to the pier and its connecting structures, placing the original upper section of the pier under vertical and transverse compression. Vertical supports are installed on both sides of the steel structure in the transverse direction, located on the upper part of the pier near the main beam. A distance ΔL1 is left between the top surface of the vertical supports and the bottom surface of the beam, where ΔL1 satisfies ΔL1=α. max ×d1+1-3mm; The vertical tie rod is located near the pier in the vertical direction. It passes through the bottom of the beam, is anchored within the beam on one side, and traverses the additional steel fiber reinforced concrete on the other side, fixing it to the steel structure. On the anchored side within the beam, a distance ΔL2 is maintained between the anchorage position and the top surface of the beam bottom, where ΔL2 satisfies ΔL2=α. max ×d2+1-3mm; α max The maximum allowable torsional angle in radians under the design load is given by d1, where d1 is the distance from the vertical support to the center of the pier, and d2 is the distance from the anchorage of the vertical tie rod to the center of the pier. The steel structure includes: an upper transverse prestressed anchoring steel structure and a lower transverse prestressed anchoring steel structure for transverse prestressing tendon threading and anchoring; a vertical support anchoring steel structure for vertical support tendon threading and lower anchoring; a bottom steel structure and a side steel structure forming an outer enclosure to provide the outermost constraint for the pouring of steel fiber reinforced concrete; and a stiffening steel structure serving as a load-bearing component connecting the overall steel structure and the steel fiber reinforced concrete.

2. The toughened column-pier bridge anti-overturning structure as described in claim 1, characterized in that: Before the steel fiber reinforced concrete is poured, vertical tie rods are inserted between the steel structure and the piers. The upper end of the tie rods is inserted into the beam through a hole drilled in the bottom of the concrete beam. After the steel fiber reinforced concrete is poured, a bond is formed between the vertical tie rods and the steel fiber reinforced concrete.

3. The toughened column-pier bridge anti-overturning structure as described in claim 1, characterized in that: After the steel fiber reinforced concrete is poured and solidified, the transverse prestressing tendons are tensioned. Under the combined action of the beam's self-weight and the transverse prestressing, the upper part of the pier is in a state of bidirectional compression, increasing its ability to withstand ultimate loads. The transverse prestressing tendons form transverse pressure in the steel structure and steel fiber reinforced concrete, thus forming prestress for the steel fiber reinforced concrete.

4. The toughened column-pier bridge anti-overturning structure as described in claim 1, characterized in that: Carbon fiber reinforcement is applied to the lower part of the bridge pier near the ground to increase the bearing capacity of the lower section of the bridge pier under eccentric load in the ultimate state.

5. The toughened column-pier bridge anti-overturning structure as described in claim 1, characterized in that... It also includes an alarm component for alarming under over-design load conditions. The alarm component includes an upper metal plate, a lower metal plate, a micro generator, a current acquisition device, and a signal transmission device. The lower metal plate is located on the top surface of the vertical support and at a relative position on the bottom surface of the beam. One end of the lower metal plate is connected to the micro generator, and the other end is connected to the current acquisition device and the signal transmission device. The upper metal plate is connected to the current acquisition device and the signal transmission device. When the upper metal plate and the lower metal plate are in contact, the current acquisition device receives the current from the micro generator, and the signal transmission device transmits an alarm signal. Under normal load conditions, the beam and vertical support do not contact each other, and the upper and lower metal plates separate, disconnecting the entire circuit and generating no signal. Under extreme load conditions, the beam and vertical support contact each other, and the upper and lower metal plates adhere to each other, connecting the circuit. The micro generator produces a small current, which is collected by the current acquisition device and sent to the signal transmission device. The signal transmission device then transmits this signal to the remote control center, enabling an alarm for extreme situations.

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