Bridge end transition slab anti-sedimentation jacking device and construction method thereof

Abstract

The invention belongs to the technical field of road and bridge construction application, and particularly relates to a bridgehead transition slab anti-sedimentation jacking device and a construction method thereof. Comprising a bridge abutment and a roadbed arranged on one side of the bridge abutment, lapping plates are arranged on the top face of the bridge abutment and the top face of the roadbed on the back of the bridge abutment, a pressure barrel is pre-buried in the roadbed on the back of the bridge abutment, a vertically-arranged piston pipe is arranged at the bottom of the pressure barrel, a piston is sleeved with the piston pipe, and a pressure disc is arranged at the end, extending out of the piston pipe, of the piston. The pressure disc is arranged in the pressure barrel in a lifting mode, the piston pipe penetrates through the bottom of the pressure barrel, an oil tank is arranged at the end, away from the pressure barrel, of the piston pipe, an output pipe is arranged on the oil tank, and a jacking oil cylinder is connected to the end, away from the oil tank, of the output pipe. According to the device provided by the invention, extra monitoring is not needed, and the jacking oil cylinder is promoted to move only by utilizing pressure change generated by natural sedimentation, so that the tower plate is supported.

Description

Technical Field

[0001] The invention belongs to the technical field of road and bridge construction applications, and in particular relates to a bridge head slab anti-settling jacking device and a construction method thereof. Background Art

[0002] The road-bridge transition section is a difficult point in road construction. The differential settlement of the bridge structure and the back-end roadbed will lead to different degrees of bridge head jump phenomenon, which seriously affects the driving comfort and safety of the road. Bridge head jump phenomenon is a common problem in road engineering. Due to the influence of factors such as traffic load, some road-bridge transition sections will experience jump disease in the early stage of road operation. Therefore, how to delay and eliminate bridge head jump disease is a difficult problem that needs to be solved urgently in the construction of roads of all levels.

[0003] Relevant studies at home and abroad have shown that the difference between the abutment structure and the embankment behind the abutment is the main reason why the bridge head jump is difficult to cure. Due to the abutment, the roadbed near the abutment is generally difficult to compact. Therefore, the significant stiffness difference between the bridge structure and the roadbed structure causes the deformation and settlement of the bridge structure to be much smaller than the compaction deformation and creep deformation of the roadbed structure and the consolidation settlement of the foundation. As a result, there is a significant misalignment at the junction of the road and bridge, resulting in the bridge head jump disease.

[0004] At present, the most widely used treatment measure to alleviate the problem of vehicle jumping at the bridge head is to set up reinforced concrete slabs in the transition section of the road and bridge. However, with the settlement of the roadbed, the slabs will appear to be empty or suspended at the bottom. For this problem, the current solution is to fill cement slurry or cement mortar under the slabs to support the slabs, which is a measure to remedy the situation. Although the above method can effectively alleviate the problem of continuous development of uneven settlement, it does not completely solve the problems of settlement and emptying in the later stage. It is necessary to monitor and detect the slabs in the long term. With the continuous increase in the mileage of highway construction in my country, the monitoring and detection costs and maintenance and treatment costs are getting higher and higher. Therefore, how to automatically support the slabs is a problem that needs to be solved at present. Summary of the invention

[0005] In view of the technical problems existing in the existing settlement treatment measures, the present invention proposes a bridgehead slab anti-settlement jacking device and a construction method thereof which has a reasonable design, a simple structure, is convenient to construct and can effectively utilize the settlement properties of roadbed fillers to automatically support the bridgehead slab.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: the present invention provides a bridge head slab anti-sinking jacking device, including an abutment and a roadbed arranged on one side of the abutment, a slab is arranged on the top surface of the abutment and the roadbed, a pressure barrel is pre-buried in the roadbed behind the abutment, a vertically arranged piston tube is arranged at the bottom of the pressure barrel, a piston is sleeved in the piston tube, a pressure plate is arranged at one end of the piston extending out of the piston tube, the pressure plate is lifted and lowered in the pressure barrel, the piston tube is arranged through the bottom of the pressure barrel, an oil tank is arranged at the end of the piston tube away from the pressure barrel, an output pipe is arranged on the oil tank, the end of the output pipe away from the oil tank is connected to a jacking cylinder, a one-way valve and a stop valve are arranged on the output pipe, and the jacking cylinder is arranged on the top of the roadbed.

[0007] Preferably, the lifting cylinder comprises a cylinder seat and a jacking rod arranged on the cylinder seat, wherein the cylinder seat is arranged in a columnar structure that is wider at the bottom and narrower at the top.

[0008] Preferably, a plug rod is provided at the bottom of the oil cylinder seat, and the plug rod is evenly distributed at the bottom of the oil cylinder seat.

[0009] Preferably, the top of the pressure barrel is arranged in a trumpet shape.

[0010] The present invention also provides a construction method for the above-mentioned bridgehead slab anti-settling jacking device, comprising the following steps:

[0011] a. First, build a reinforced concrete enlarged base at the base of the abutment roadbed. After the reinforced concrete base reaches the 7d compressive strength, backfill and compact the abutment roadbed in layers. Permeable graded crushed stone fillers or inorganic bonded treatment fillers with good water stability are preferred. When compacting the roadbed, use a roller to vibrate and compact it at locations far from the abutments, and use a light plate compactor to compact it within 1m of the abutments;

[0012] b. Then, reverse excavation is carried out at the location where the concrete foundation is buried to clean the surface of the concrete foundation.

[0013] Fix the pressure barrel and oil tank on the reinforced concrete base and connect the output pipe;

[0014] c. After the connection is tight, use graded crushed stone to backfill the reverse excavation area in layers, and use light plate compactor to fill the reverse excavation area in layers.

[0015] During the layer compaction and backfill compaction process, ensure that the outlet pipe opening is exposed;

[0016] d. After the backfill is compacted, fill the oil tank with hydraulic oil to keep the piston in the lifted state.

[0017] Close the stop valve to maintain the height of the pressure plate;

[0018] e. Then, dig a hole on the top surface of the roadbed to place the jacking cylinder, making sure that the top of the jacking cylinder is

[0019] The surface is flush with the top surface of the roadbed;

[0020] f. Measure the oil pressure in the output pipe, and then determine the opening pressure of the one-way valve according to the oil pressure. After selecting the type, install the one-way valve and open the stop valve;

[0021] g. After connecting the jacking cylinder to the output pipe, place the jacking cylinder into the pit;

[0022] h. Finally, lay the planks and the road surface.

[0023] Compared with the prior art, the advantages and positive effects of the present invention are:

[0024] 1. The present invention provides a bridgehead slab anti-settling jacking device, which utilizes settlement to cause the roadbed filler in the pressure barrel to be compacted and deformed, and the density to increase, thereby generating the characteristic of increased gravity to prompt the piston to move downward to squeeze the hydraulic oil in the oil tank to move toward the jacking cylinder, so that the jacking rod moves, thereby ensuring the support of the slab. The device provided by the present invention does not require additional monitoring and subsequent regular inspections, and only utilizes the pressure changes caused by natural settlement to prompt the jacking cylinder to move, thereby completing the support of the tower plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A schematic diagram of the structure of the anti-settling jacking device for the bridgehead slab provided in Example 1;

[0027] Figure 2 A cross-sectional view of the pressure barrel provided in Example 1;

[0028] Figure 3 A schematic diagram of the structure of the jacking cylinder provided in Example 1;

[0029] In the above figures, 1, abutment; 11, corbel; 2, cladding; 3, roadbed; 4, pressure barrel; 41, piston tube; 42, piston; 43, pressure plate; 44, annular boss; 5, oil tank; 6, output pipe; 7, lifting cylinder; 71, cylinder seat; 72, jack; 73, plug rod. DETAILED DESCRIPTION

[0030] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0032] Embodiment 1, as Figure 1 to Figure 3 As shown, the present embodiment aims to provide a device capable of providing support at all times according to the amount of settlement. To this end, in order to achieve the above-mentioned purpose, the present embodiment provides a bridge head slab 2 anti-settlement jacking device, comprising an abutment 1 and a roadbed 3 arranged on one side of the abutment 1, and a slab 2 is arranged on the top surface of the abutment 1 and the roadbed 3. The above structure is an existing common structure, so it is not described in detail in the present embodiment.

[0033] Considering that the main reason for the differential settlement at the bridgehead back is that the filler structure of the roadbed 3 has elastic-plastic characteristics, and there are gaps between the particles of the roadbed 3, with the vibration of road vehicles, upper loads and other reasons, the gaps between the particles are compressed, and the roadbed 3 undergoes elastic-plastic deformation, thereby causing the height of the roadbed 3 to drop, resulting in compaction settlement, and the increase in the density of the roadbed 3 causes the filler weight in a fixed volume to increase, so that the local pressure in the pressure barrel 4 also increases, then using this pressure change of settlement as a driving force, it is possible to achieve support according to its situation at all times. For this reason, in this embodiment, a pressure barrel 4 is pre-buried in the roadbed 3. Considering that the filling volume of the roadbed 3 above the pressure barrel 4 is certain, in this case, the total soil pressure on the upper part will not change significantly. For this reason, it is necessary to obtain the surrounding roadbed 3 filler to obtain a more accurate weight change. For this reason, in this embodiment, the top of the pressure barrel 4 is arranged in a trumpet shape, so that the trumpet-shaped opening will form a certain guiding effect, so that the surrounding filler can enter the pressure barrel 4, thereby changing the internal pressure of the pressure barrel.

[0034] In order to utilize this increase in pressure, in the present embodiment, a vertically arranged piston tube 41 is provided at the bottom of the pressure barrel 4. In order to ensure the stability of the piston tube 41 and the stability of the entire pressure barrel 4, in the present embodiment, the pressure barrel 4 is also cast as a whole by reinforced concrete, and the thickness of its bottom is at least 20 cm. A piston 42 is mounted in the piston tube 41. The piston 42 is slidably arranged in the piston tube 41. A pressure plate 43 is provided at one end of the piston 42 extending out of the piston tube 41. The pressure plate 43 is raised and lowered in the pressure barrel 4. The diameter of the pressure plate 43 is substantially the same as the inner diameter of the middle part of the pressure barrel 4. This can prevent the filler of the back-stage roadbed 3 from entering the bottom of the pressure plate 43 and affecting the descent of the pressure plate 43 as much as possible.

[0035] A piston tube 41 is arranged to pass through the bottom of the pressure barrel 4, and an oil tank 5 is arranged at the end of the piston tube 41 away from the pressure barrel 4. An output pipe 6 is arranged on the oil tank 5. The oil tank 5 is filled with hydraulic oil, and a lifting cylinder 7 is connected to the end of the output pipe 6 away from the oil tank 5. The lifting cylinder 7 adopts a structure similar to that of a jack, except that the pressing structure of the jack is replaced with the pressure barrel 4. At the same time, in order to prevent the hydraulic oil from flowing in reverse, a one-way valve and a stop valve are arranged on the output pipe 6. Specifically, the stop valve is arranged closer to the oil tank 5 than the one-way valve. This arrangement is for coordination with implementation.

[0036] Since the jacking oil cylinder 7 is to support the butt plate 2, for this reason, the jacking oil cylinder 7 is arranged on the top of the roadbed 3. The output end of the jacking oil cylinder 7 can be arranged in contact with the butt plate 2.

[0037] Through the above arrangement, as the sedimentation occurs, the filler entering the pressure barrel 4 becomes larger and larger, and the increase in its weight leads to an increase in the pressure on the pressure plate 43, thereby forcing the pressure plate 43 to move downward, and the piston 42 moves downward, squeezing the hydraulic oil into the jacking cylinder 7, thereby causing the power end of the jacking cylinder 7 to extend and maintain support for the tower plate. It should be noted that the number of the entire jacking device needs to be calculated according to the area of ​​the butt plate 2 to ensure the stability of the butt plate 2.

[0038] Considering that the lifting cylinder 7 needs to support the butt plate 2, the lifting cylinder 7 is subjected to the reaction force of the butt plate 2. Therefore, in order to maintain the stability of the supporting force, in this embodiment, the lifting cylinder 7 includes a cylinder seat 71 and a push rod 72 arranged on the cylinder seat 71, wherein the cylinder seat 71 is arranged in a columnar structure with a wide bottom and a narrow top. The purpose of such arrangement is to reduce the force-bearing area and increase the supporting area, thereby ensuring the support.

[0039] Considering that there is a certain imbalance in the process of settlement, and this imbalance causes the lifting cylinder 7 to tilt, in this embodiment, a plug rod 73 is provided at the bottom of the cylinder seat 71, and the plug rod 73 is evenly distributed at the bottom of the cylinder seat 71. The length of the plug rod 73 is about 50 cm, because the settlement is a slow settlement, therefore, under the action of the plug rod 73, the entire lifting cylinder 7 will follow the settlement downward, but it is not easy to tilt.

[0040] During the specific construction, the support points required for the slab 2 to maintain its state are first calculated, and then a reinforced concrete base is constructed at the position of the corresponding support points at the bottom of the roadbed 3. The reinforced concrete base is set to prevent the pressure barrel 4 from falling.

[0041] To this end, the back of the abutment should be backfilled and compacted in layers after the reinforced concrete base reaches the 7d compressive strength. When backfilling and compacting the back of the abutment in layers, a roller is used for vibration compaction at a position far away from the abutment 1, and a light flat plate compactor is used for compaction within 1m of the abutment to prevent damage to the bridge structure caused by close-range heavy machinery vibration compaction.

[0042] After completing the backfill of the platform, back-excavate the area where the jacking device is to be installed. Back-excavate to the reinforced concrete foundation, clean the surface, fix the pressure barrel 4 and the oil tank 5 on the reinforced concrete foundation and connect the output pipe 6. The oil tank 5 is protected in the reinforced concrete foundation as much as possible.

[0043] Then, the counter-excavation area is backfilled in layers with graded crushed stone and compacted in layers with a small hydraulic rammer. During the backfilling process, it is necessary to ensure that the outlet of the output pipe 6 is exposed.

[0044] After the backfilling is completed, hydraulic oil is injected into the oil tank 5 to keep the piston 42 in a lifted state. At this time, the pressure barrel 4 constitutes an oil cylinder. The main purpose of not filling the hydraulic oil during the backfilling process is to accurately determine the oil pressure. At this time, the pressure required for lifting is the pressure currently exerted on the pressure plate 43. Then, the stop valve is closed to maintain the height of the pressure plate 43.

[0045] A hole is dug on the top surface of the roadbed 3 for placing the jacking cylinder 7, ensuring that the top surface of the jacking cylinder 7 is flush with the top surface of the roadbed 3 cylinder.

[0046] Next, measure the oil pressure in the output pipe 6, and then determine the opening pressure of the one-way valve according to the size of the oil pressure. After selecting the type, install the one-way valve and open the stop valve. Since the opening pressure of the one-way valve is slightly greater than the oil pressure at this time, the one-way valve replaces the stop valve to complete the closure.

[0047] Next, after the jacking cylinder 7 is connected to the output pipe 6, the jacking cylinder 7 is placed in the pit, and the amount of hydraulic oil in the jacking cylinder 7 is not enough to drive the push rod 72 to extend. Finally, the paving board 2 and the road surface are laid.

[0048] Through the above arrangement, the pressure generated by the settlement is effectively converted into a driving force, thereby driving the top rod 72 to rise. The height of the top rod 72 rising is linearly related to the settlement amount, thereby ensuring support.

[0049] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A bridge head slab anti-settling jacking device, comprising a bridge abutment and a roadbed arranged on the back side of the bridge abutment, wherein a slab is arranged on the top surface of the abutment and the roadbed, and characterized in that: A pressure barrel is pre-buried in the roadbed, and a vertically arranged piston tube is provided at the bottom of the pressure barrel. A piston is mounted in the piston tube, and a pressure plate is provided at one end of the piston extending out of the piston tube. The pressure plate is raised and lowered in the pressure barrel, and the piston tube passes through the bottom of the pressure barrel, and an oil tank is provided at the end of the piston tube away from the pressure barrel. An output pipe is provided on the oil tank, and a lifting cylinder is connected to the end of the output pipe away from the oil tank. A one-way valve and a stop valve are provided on the output pipe, and the lifting cylinder is arranged on the top of the roadbed.

2. The anti-settling jacking device for bridgehead slab according to claim 1 is characterized in that: The lifting cylinder comprises a cylinder seat and a jacking rod arranged on the cylinder seat, wherein the cylinder seat is arranged in a columnar structure which is wide at the bottom and narrow at the top.

3. The anti-settling jacking device for bridgehead slab according to claim 2 is characterized in that: The bottom of the oil cylinder seat is provided with insertion rods, and the insertion rods are evenly distributed at the bottom of the oil cylinder seat.

4. The anti-settling jacking device for bridgehead slab according to claim 4 is characterized in that: The top of the pressure barrel is arranged in a trumpet shape.

5. The construction method of the bridge slab anti-settling jacking device according to claim 4 is characterized in that: The following steps are involved: a. First, build a reinforced concrete enlarged base at the base of the abutment roadbed. After the reinforced concrete base reaches the 7d compressive strength, backfill and compact the abutment roadbed in layers. Permeable graded crushed stone fillers or inorganic bonded treatment fillers with good water stability are preferred. When compacting the roadbed, use a roller to vibrate and compact it at locations far from the abutments, and use a light plate compactor to compact it within 1m of the abutments; b. Then, reverse excavation is carried out at the location where the concrete expansion foundation is buried, the surface of the concrete foundation is cleaned, the pressure barrel and the oil tank are fixed on the reinforced concrete base and the output pipe is connected; c. After the connection is tight, use graded crushed stone to backfill the reverse excavation area in layers, and use a light plate compactor to compact in layers. During the backfilling and compaction process, ensure that the outlet of the output pipe is exposed; d. After backfilling and compaction, fill the oil tank with hydraulic oil to keep the piston in the lifted state. At the same time, close the stop valve to maintain the height of the pressure plate; e. Then, dig a hole on the top surface of the roadbed for placing the jacking cylinder, and ensure that the top surface of the jacking cylinder is flush with the top surface of the roadbed; f. Measure the oil pressure in the output pipe, and then determine the opening pressure of the one-way valve according to the oil pressure. After selecting the type, install the one-way valve and open the stop valve; g. After connecting the jacking cylinder to the output pipe, place the jacking cylinder into the pit; h. Finally, lay the planks and the road surface.

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