Method for realizing bridge pushing based on electromagnet

Abstract

The invention discloses a method for realizing bridge incremental launching based on electromagnets, and relates to the technical field of bridge incremental launching construction. Comprising the steps that when a box girder body is pushed to a stainless steel plate sliding way to be just attached to the top face of a cavity carrier, gas in the cavity carrier is squeezed preliminarily, pressure sensors on the two sides sense pressure changes, collected interaction force at the moment is set to be a preset value, and when an electric signal received by a microprocessor is a preset value, the microprocessor controls the pressure sensors to sense the pressure changes; the first electromagnet or the second magnet starts to generate magnetism; the box girder body is continuously pushed forwards, in the process, the contact area of the stainless steel plate sliding way and the polytetrafluoroethylene sliding block is slowly increased to the maximum, and the pressure F change sensed by the pressure sensors on the two sides is gradually increased and then tends to be stable; the strength of electromagnetic force can be controlled by arranging the electromagnet and adjusting the current of the electromagnet, so that the stainless steel plate is lifted, the friction force between the stainless steel plate and the polytetrafluoroethylene sliding block is reduced, the abrasion of the sliding block is reduced, the continuous pushing effect is achieved, and the construction efficiency is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of bridge jacking construction, and in particular to a method for realizing bridge jacking based on an electromagnet. Background Art

[0002] With the increasing application of bridge jacking method in the field of bridge construction, a key link in its construction process is to ensure that the jacking structure can move forward smoothly and efficiently, which undoubtedly requires overcoming the frictional resistance generated on the forward path. In response to this demand, the existing patent CN102071642B proposes an improved slideway scheme for steel truss jacking construction. The upper slideway in this scheme adopts a construction method in which the stainless steel plate slideway is tightly connected end to end, while the lower slideway is a fixed main steel plate laid on the pier, and a polytetrafluoroethylene slide plate is installed on top of it. The upper and lower slideways of this device are respectively attached to the bottom surface of the beam body and the top surface of the pier. It not only has a suitable length to ensure the stability of sliding, but also has a flat and smooth surface, excellent rigidity, a simple and clear structure, and is extremely easy to disassemble. More importantly, the connection between the device and the jacking structure and the pier is firm and reliable, ensuring safety during the construction process.

[0003] However, despite the excellent performance of the device in many aspects, the relatively limited contact area between the bottom surface of the main longitudinal beam of the steel truss and the pier slideway increases the difficulty of construction to a certain extent. Especially during the jacking process, the polytetrafluoroethylene slide plate is prone to offset due to uneven force, thereby deviating from the predetermined jacking track, which brings challenges to construction control and direction adjustment. Although the smooth surface of the polytetrafluoroethylene slide plate helps to reduce the friction resistance between the stainless steel plate slideway, this material is very easy to wear after long-term use, which in turn affects the sliding effect, resulting in a significant reduction in construction efficiency and difficulty in ensuring the rapid and continuous jacking construction. Summary of the invention

[0004] The purpose of the present invention is to provide a method for realizing bridge jacking based on electromagnets, which can optimize the mechanical balance during the jacking process by dynamically adjusting the friction force, thereby realizing a smoother and more continuous jacking operation.

[0005] To achieve the above purpose, the technical solution of the present application is: a method for realizing bridge jacking based on electromagnets, comprising:

[0006] The stainless steel plate slideway is embedded in the bottom of the box beam body, and the inner wall of the stainless steel plate slideway is in contact with the polytetrafluoroethylene slider, and the polytetrafluoroethylene slider is placed on the load-bearing steel plate box structure;

[0007] Cavity carriers are embedded on both sides of the polytetrafluoroethylene slider, and a pressure sensor is installed in each cavity carrier;

[0008] A first electromagnet is provided on both sides of the bottom of the stainless steel plate slideway, and a second electromagnet is provided on both sides of the top of the load-bearing steel plate box structure. The first electromagnet and the second electromagnet on the same side are arranged opposite to each other and have the same magnetic poles.

[0009] When the box girder body is pushed forward until the stainless steel plate slideway just touches the top surface of the cavity carrier, the gas in the cavity carrier is initially squeezed, and the pressure sensors on both sides feel the pressure change. The interaction force collected at this time is set to the preset value F0. When the microprocessor receives the electrical signal of the preset value F0, the first electromagnet or the second magnet starts to generate magnetism;

[0010] The box girder body is continuously pushed forward, during which the contact area between the stainless steel plate slideway and the polytetrafluoroethylene slider slowly increases to the maximum, and the pressure F sensed by the pressure sensors on both sides gradually increases and then tends to be stable; when the pressure F is greater than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is increased, so the electromagnetic force generated is increased to lift the stainless steel plate slideway, thereby reducing the friction between it and the polytetrafluoroethylene slider; during the lifting process, when the pressure F is less than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is reduced, thereby achieving stable advancement.

[0011] As a preferred solution of the present invention, when the box girder body is not pushed or is not pushed to the middle of the pier, the stainless steel plate slideway is not in contact with the polytetrafluoroethylene slider, and the pressure sensor does not sense the pressure change.

[0012] As a preferred solution of the present invention, the top surface and two side surfaces of the polytetrafluoroethylene slider are smooth surfaces, and the smooth surfaces are in contact with the inner wall of the stainless steel plate slideway.

[0013] As a preferred solution of the present invention, slide grooves are provided on both sides of the stainless steel plate slideway, and the top of the load-bearing steel plate box structure is placed in the slide grooves.

[0014] As a preferred solution of the present invention, slider baffles are provided at both ends of the load-bearing steel plate box structure for limiting the position of the polytetrafluoroethylene slider.

[0015] As a preferred solution of the present invention, the pressure sensor is connected to a microprocessor via a signal conversion circuit and a filter amplifier circuit, and the microprocessor controls the magnitude of the current flowing through the first electromagnet or the second electromagnet.

[0016] As a preferred solution of the present invention, the pressure sensors on both sides are arranged symmetrically, and the microprocessor controls the first electromagnet or the second electromagnet on the corresponding side through the collected pressure F.

[0017] As a preferred solution of the present invention, the outer wall of the cavity carrier is tightly bonded to the polytetrafluoroethylene slider, and the gas pressure in the cavity carrier changes when the stainless steel plate slide moves.

[0018] As a preferred solution of the present invention, the bottom end of the load-bearing steel plate box structure is respectively connected with a front baffle and a rear baffle, and the front baffle and the rear baffle are both in contact with the support pedestal stone, and the load-bearing steel plate box structure is fixed to the support pedestal stone by temporary anchor bolts.

[0019] As a preferred solution of the present invention, the cavity carrier is made of a polyester material that is resilient and airtight, and the cavity carrier can quickly return to its original state after being compressed.

[0020] Due to the adoption of the above technical solution, the present invention can achieve the following technical effects: by setting an electromagnet and adjusting its current, the strength of the electromagnetic force can be controlled, thereby lifting the stainless steel plate, reducing the friction between the stainless steel plate slide and the polytetrafluoroethylene slider, reducing the wear of the slider, achieving a continuous push effect, and ensuring construction efficiency. In addition, the stainless steel plate slide is designed with a slide groove, which can effectively maintain the direction of movement and avoid deviation from the push track. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is a front view of the push structure involved in the present invention;

[0023] Figure 2 It is a cross-sectional view of the load-bearing steel plate box structure involved in the present invention;

[0024] Figure 3 It is a side view of the push structure involved in the present invention;

[0025] Figure 4 It is a cross-sectional view of the push structure involved in the present invention;

[0026] Figure 5 This is a schematic diagram of the electrical signal connection involved in the present invention.

[0027] Explanation of the serial numbers in the figure: 1-slider baffle, 2-cavity carrier, 3-pressure sensor, 4-stainless steel plate slide, 5-first electromagnet, 6-polytetrafluoroethylene slider, 7-load-bearing steel plate box structure, 8-front baffle, 9-rear baffle, 10-microprocessor, 11-box beam body, 12-support pad stone, 13-temporary anchor bolt, 14-pier. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0029] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0031] In the description of the present application, it should be understood that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0032] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] Example 1

[0034] See also Figure 1-4, this embodiment provides a slideway improvement device for implementing the above method, including a slider baffle 1, a cavity carrier 2, a pressure sensor 3, a stainless steel plate slideway 4, a first electromagnet 5, a second electromagnet, a polytetrafluoroethylene slider 6, and a load-bearing steel plate box structure 7; the top surface and the two side surfaces of the polytetrafluoroethylene slider are smooth surfaces, and the smooth surfaces are in contact with the inner wall of the stainless steel plate slideway, and the stainless steel plate slideway is pre-buried in the bottom of the box beam body through shear nails; the polytetrafluoroethylene slider is placed on the load-bearing steel plate box structure and is limited by the slider baffles at both ends of the load-bearing steel plate box structure; cavity carriers are embedded on both sides of the polytetrafluoroethylene slider, and a pressure sensor is installed in each cavity carrier. The pressure sensor 3 collects the interaction force between the stainless steel plate slideway 4 and the polytetrafluoroethylene slider 6, and converts the signal into an electrical signal through a signal conversion circuit and a filter amplifier circuit and transmits it to the microprocessor 10. The microprocessor 10 controls the current of the first electromagnet 5 or the second electromagnet, such as Figure 5 As shown; first electromagnets are respectively provided on both sides of the bottom of the stainless steel plate slideway, and second electromagnets are respectively provided on both sides of the top of the load-bearing steel plate box structure, and the first electromagnet and the second electromagnet on the same side are arranged oppositely and have the same magnetic poles;

[0035] In this embodiment, the two sides of the stainless steel plate slideway are provided with slide grooves, and the top of the load-bearing steel plate box structure is placed in the slide grooves to maintain the sliding direction of the top push and the fixed position of the polytetrafluoroethylene slider to ensure the top push efficiency. The traditional slideway is prone to derailment, and the position of the slideway and the polytetrafluoroethylene slider must be checked frequently. If deformation and sliding are found, it is necessary to stop the top push immediately and readjust the slideway, which will delay the construction progress. The load-bearing steel plate box structure is preferably made of Q345D steel plates welded together.

[0036] In this embodiment, the bottom ends of the load-bearing steel plate box structure 7 are respectively provided with a front baffle 8 and a rear baffle 9, and the front baffle and the rear baffle are both in contact with the support cushion stone. The load-bearing steel plate box structure 7 is fixedly connected to the support cushion stone 12 by a plurality of temporary anchor bolts 13 to prevent slipping in the pushing direction; the support cushion stone 12 is placed on the pier 14.

[0037] Example 2

[0038] This embodiment provides a method for realizing bridge jacking based on electromagnets, comprising:

[0039] The stainless steel plate slideway is embedded in the bottom of the box beam body, and the inner wall of the stainless steel plate slideway is in contact with the polytetrafluoroethylene slider, and the polytetrafluoroethylene slider is placed on the load-bearing steel plate box structure;

[0040] Cavity carriers are embedded on both sides of the polytetrafluoroethylene slider, and a pressure sensor is installed in each cavity carrier;

[0041] A first electromagnet is provided on both sides of the bottom of the stainless steel plate slideway, and a second electromagnet is provided on both sides of the top of the load-bearing steel plate box structure. The first electromagnet and the second electromagnet on the same side are arranged opposite to each other and have the same magnetic poles.

[0042] When the box girder body is not pushed or is not pushed to the middle of the pier, the stainless steel plate slideway is not in contact with the polytetrafluoroethylene slider, and the pressure sensor does not sense the pressure change;

[0043] When the box girder body is pushed forward until the stainless steel plate slideway just touches the top surface of the cavity carrier, the gas in the cavity carrier is initially squeezed, and the pressure sensors on both sides feel the pressure change. The interaction force collected at this time is set to the preset value F0. When the microprocessor receives the electrical signal of the preset value F0, the first electromagnet or the second magnet starts to generate magnetism;

[0044] The box girder body is continuously pushed forward, and during this process, the contact area between the stainless steel plate slide and the polytetrafluoroethylene slider slowly increases to the maximum. The pressure F sensed by the pressure sensors on both sides gradually increases and then tends to be stable, which affects the size of the electrical signal received by the microprocessor 10, and controls the current passing through the first electromagnet 5 or the second electromagnet on both sides respectively to generate the required magnetism, so as to generate a thrust that can lift the stainless steel plate slide 4. Specifically, when the pressure F is greater than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is increased, so the electromagnetic force generated is increased to lift the stainless steel plate slide, thereby reducing the friction between it and the polytetrafluoroethylene slider; during the lifting process, when the pressure F is less than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is reduced, thereby achieving stable advancement.

[0045] In this embodiment, the box girder body is 5m wide, 1.5m high, and made of Q234q steel; the slideway is 6m long and 4m wide. The pressure F received by the microprocessor is 312.57kN, and the surface area S of the pressure sensor 3 is 1 0.1m 2 , the contact area S between the pressure sensor 3 and the stainless steel plate 4 2 0.3m 2 , the pressure of stainless steel slideway 4 According to Maxwell's electromagnetic theory, the current n is the number of turns of the electromagnet coil, which is 50,000, μ 0 The magnetic permeability is 4π×10 -7 N / A 2 , S 0 The air gap area is 2×10 -3 m 2 , σ 0 The air gap thickness can be 1.5×10 -3m, when the electromagnetic force is equal to 937.71 kN, that is, the current I = 0.16 A, the electromagnetic force generated is equal to the pressure, and the first electromagnet 5 generates magnetism to lift the stainless steel plate slide 4, reducing the contact area between the stainless steel plate slide 4 and the polytetrafluoroethylene slider 6, reducing wear, thereby achieving the purpose of reducing the friction of the slide, extending the service life, and ensuring construction efficiency; when the pressure signal sensed by the pressure sensor 3 is the same as the initial state, the microprocessor cuts off the power to the first electromagnet 5 or the second electromagnet.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for realizing bridge jacking based on electromagnets, characterized in that: include: The stainless steel plate slideway is embedded in the bottom of the box beam body, and the inner wall of the stainless steel plate slideway is in contact with the polytetrafluoroethylene slider, and the polytetrafluoroethylene slider is placed on the load-bearing steel plate box structure; Cavity carriers are embedded on both sides of the polytetrafluoroethylene slider, and a pressure sensor is installed in each cavity carrier; A first electromagnet is provided on both sides of the bottom of the stainless steel plate slideway, and a second electromagnet is provided on both sides of the top of the load-bearing steel plate box structure. The first electromagnet and the second electromagnet on the same side are arranged opposite to each other and have the same magnetic poles. When the box girder body is pushed forward until the stainless steel plate slideway just touches the top surface of the cavity carrier, the gas in the cavity carrier is initially squeezed, and the pressure sensors on both sides feel the pressure change. The interaction force collected at this time is set to the preset value F0. When the microprocessor receives the electrical signal of the preset value F0, the first electromagnet or the second magnet starts to generate magnetism; The box girder body is continuously pushed forward, during which the contact area between the stainless steel plate slideway and the polytetrafluoroethylene slider slowly increases to the maximum, and the pressure F sensed by the pressure sensors on both sides gradually increases and then tends to be stable; when the pressure F is greater than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is increased, so the electromagnetic force generated is increased to lift the stainless steel plate slideway, thereby reducing the friction between it and the polytetrafluoroethylene slider; during the lifting process, when the pressure F is less than the preset value F0, the current flowing through the first electromagnet or the second electromagnet is reduced, thereby achieving stable advancement.

2. According to claim 1, a method for realizing bridge jacking based on electromagnets is characterized in that: When the box girder body is not pushed or is not pushed to the middle of the pier, the stainless steel plate slideway is not in contact with the polytetrafluoroethylene slider, and the pressure sensor does not sense the pressure change.

3. According to claim 1, a method for realizing bridge jacking based on electromagnets is characterized in that: The top surface and two side surfaces of the polytetrafluoroethylene sliding block are smooth surfaces, and the smooth surfaces are in contact with the inner wall of the stainless steel plate slideway.

4. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: Slide grooves are arranged on both sides of the stainless steel plate slideway, and the top of the load-bearing steel plate box structure is placed in the slide grooves.

5. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: Slider baffles are provided at both ends of the load-bearing steel plate box structure for limiting the position of the polytetrafluoroethylene slider.

6. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: The pressure sensor is connected to a microprocessor via a signal conversion circuit and a filter amplifier circuit, and the microprocessor controls the magnitude of the current flowing through the first electromagnet or the second electromagnet.

7. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: The pressure sensors on both sides are arranged symmetrically, and the microprocessor controls the first electromagnet or the second electromagnet on the corresponding side through the collected pressure F.

8. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: The outer wall of the cavity carrier is tightly bonded to the polytetrafluoroethylene slider, and the gas pressure in the cavity carrier changes when the stainless steel plate slide moves.

9. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: The bottom ends of the load-bearing steel plate box structure are respectively connected with a front baffle and a rear baffle, and the front baffle and the rear baffle are both in contact with the support pad stone, and the load-bearing steel plate box structure is fixed on the support pad stone by temporary anchor bolts.

10. The method for realizing bridge jacking based on electromagnet according to claim 1, characterized in that: The cavity carrier is made of a polyester material that is resilient and airtight.

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