An intelligent control system for the lateral temperature gradient effect of a movable bridge

Abstract

The present invention provides an intelligent regulation system for the lateral temperature gradient effect of a portable beam, which includes a side support steel beam, a heat dissipation elastic pad, an excitation device, a temperature sensor, a thermometer, an anemometer, a solar radiation meter, a data acquisition instrument, and a processing terminal. The principle of the present invention is as follows: an eccentric force is applied at both ends of the portable beam through the excitation device to form an equivalent bending moment to resist the bending effect caused by the temperature gradient. This system controls the structural side bending through the side support steel beam and the heat dissipation elastic pad while releasing a certain amount of temperature internal force, which is beneficial to the structural safety. This system is based on machine learning, and uses a neural network to construct and train a regulation model for the lateral temperature gradient effect to achieve real-time monitoring and intelligent regulation of the temperature gradient effect. The present invention has low cost, is convenient for installation and maintenance, and can be remotely controlled to achieve intelligent regulation and monitoring visualization.

Description

Technical Field

[0001] The present invention belongs to the field of health detection of building structures, and particularly relates to an intelligent control system for the lateral temperature gradient effect of a temporary beam. Background Technique

[0002] In recent years, the number of urban road and existing railway interchange projects has been increasing day by day. When the road adopts the underpass railway plan, large-span jacked frame bridges are mostly used. During the construction of railway bridge and culvert jacking, in order not to interrupt railway transportation, the line needs to be reinforced. Among them, the temporary beam has been widely used due to its advantages such as light self-weight, high strength, and convenient construction.

[0003] However, the temporary beam also has its disadvantages. It has a large coefficient of thermal expansion and is easily affected by temperature changes. Under the action of the solar radiation temperature difference, the cross-section temperature of the temporary beam shows a non-linear change, which will also affect the geometric shape and internal force state of the structure to a large extent. Due to uneven sunlight irradiation, there is a large lateral temperature gradient on both sides of the temporary beam, resulting in the tendency of the end of the high-temperature side of the temporary beam to bend outward, which causes the coordinated deformation of the rail and has an adverse impact on the driving safety.

[0004] With the increasingly wide application of the temporary beam, the research on how to control the lateral temperature gradient effect of the temporary beam has become particularly urgent. It is very important to strictly control the geometric shape and lateral deformation. And the sunlight irradiation will shift with time, resulting in continuous changes in the temperature gradient of the structure. Moreover, the temperature effect of the temporary beam is closely related to factors such as geographical location, beam orientation, temperature, wind speed, solar radiation intensity, and structural cross-section shape.

[0005] How to effectively control the lateral displacement and temperature internal force caused by the temperature gradient effect of the temporary beam has become a difficult problem that many construction departments urgently need to solve. At present, many construction units limit the lateral displacement caused by temperature by padding wooden blocks on both sides of the temporary beam. This method utilizes the characteristics of wood materials to release a certain amount of temperature stress while resisting the deformation of the temporary beam. However, the temperature gradient of the structure changes in real time, and this method cannot monitor and visualize the impact of the temperature gradient effect on the structure in real time and lacks theoretical basis. Summary of the Invention

[0006] The purpose of the present invention is to provide an intelligent control system for the lateral temperature gradient effect of a temporary beam. By applying eccentric forces at both ends of the temporary beam to form an equivalent bending moment, the bending effect caused by the lateral temperature gradient is resisted, and the impact of the lateral temperature gradient effect on the structure is monitored in real time.

[0007] To achieve the above purpose, the present invention provides the following technical solution: An intelligent control system for the lateral temperature gradient effect of a temporary beam, comprising a side support steel beam (1), a heat dissipation elastic pad (2), a temperature sensor (4), an excitation device (3), and a processor (9);

[0008] The side support steel girders (1) are respectively pre-buried and anchored in the foundation in advance and arranged on both horizontal sides of the bridge girder. The heat dissipation elastic pads (2) are used to firmly bond the bridge girder and the side support steel girders (1) where they are located, limit the lateral bending of the bridge girder, and release a certain amount of temperature internal force at the same time.

[0009] The excitation device (3) is attached to both radial ends of the bridge girder where it is located and is connected to the steel wire ropes arranged on the bridge girder; the temperature sensor (4) is placed on the surface of the web of the bridge girder to detect the real-time temperature of the bridge girder and output a signal to the processor (9) connected thereto.

[0010] The processor (9) is connected to the excitation device (3). After receiving the signal output from the temperature sensor (4), it uses the trained lateral temperature gradient effect regulation model to control the excitation device (3) connected thereto, applies an eccentric force to the bridge girder where the excitation device is attached to form an equivalent bending moment, and resists the bending effect caused by the lateral temperature gradient on the bridge girder. At the same time, the processor (9) detects the change trend of the temperature difference between the two sides of the bridge girder caused by the sun exposure offset according to the temperature sensor (4), and controls the excitation device (3) connected thereto to realize the steering of the eccentric force according to the preset threshold of the system.

[0011] Further, the aforementioned excitation device (3) includes a rubber pad (10), a jack (11), a gravity base (12), a piston device (13), and a support structure (14); one end of the support structure (14) is installed on the gravity base (12), and the other end is movably connected to one end of the jack (11) through the piston device (13). The other end of the jack (11) is the rubber pad (10), and the rubber pad (10) is attached to the bridge girder. The jack (11) is used to jack up to generate an eccentric pressure facing the bridge girder and a tensile force away from the bridge girder, and the rubber pad (10) is used to prevent the bridge girder from deforming due to stress concentration.

[0012] Further, the aforementioned eccentric force is obtained according to the following steps:

[0013] S1. The environmental detection device (15) respectively collects the air temperature, wind speed, and maximum solar radiation amount in the area where the bridge girder is located through the thermometer (5), anemometer (6), and pyranometer (7) included therein.

[0014] S2. According to the air temperature, wind speed, and maximum solar radiation amount in the area where the bridge girder is located obtained in step S1, the daily maximum air temperature, daily minimum air temperature, daily average wind speed, and daily maximum solar radiation amount in the area where the bridge girder is located are further obtained.

[0015] S3. Calculate the temperature difference at a distance x from the surface of the bridge girder according to the following formula:

[0016]

[0017] Among them, α s is the coefficient of linear expansion, T 0 is the temperature variation range in the region where the variable is located.

[0018] U is the daily maximum solar radiation, T max is the daily maximum temperature, T min is the daily minimum temperature, and v is the daily average wind speed.

[0019] S4. Calculate the self-stress generated by the temperature gradient according to the following formula:

[0020] σ(x) = E[α s ·T(x) - (ε 0 + φx)],

[0021] Among them, φ is the curvature of the cross-section deformation, ε 0 is the strain at the cross-section transverse x = 0,

[0022] S5. Calculate the bending moment value generated by the non-linear temperature distribution according to the following formula:

[0023]

[0024] Among them, E is the elastic modulus; b is the cross-section width, x 0 is the distance from the cross-section end to the centroid axis, h(x) is the cross-section height at x, and I is the cross-section moment of inertia.

[0025] S6. Calculate the eccentric force according to the following formula:

[0026] Furthermore, the aforementioned trained lateral temperature gradient effect regulation model is obtained according to the following steps:

[0027] S11. Based on the temperature, wind speed, and solar radiation of the environment where the portable beam is located detected by the environmental detection device (15) placed in the preset range near the portable beam, output the detected temperature, wind speed, and solar radiation environment data to the data acquisition device (8) connected thereto; and output the environment data to the processor (9). S21. Using the daily temperature, daily wind speed, and daily maximum solar radiation in the area where the portable beam is located as the input and the corresponding eccentric force applied to the portable beam as the output, construct and train to obtain the lateral temperature gradient effect regulation model.

[0028] Furthermore, the aforementioned excitation device (3) acts on the temporary beam with a pair of eccentric forces respectively through the displacement of the piston device (13): a thrust force facing the temporary beam and a tensile force away from the temporary beam. Each pair of eccentric forces is equal in magnitude and opposite in direction. The thrust force facing the temporary beam is generated by the jack (11) lifting, and the tensile force away from the temporary beam is generated by the jack (11) tensioning the steel wire ropes arranged on the temporary beam it is connected to.

[0029] Furthermore, 4 excitation devices (3) are arranged to fit at both radial ends of the temporary beam where they are located. Description of the Drawings

[0030] Figure 1 is the schematic diagram of the principle of the intelligent control system for the lateral temperature gradient effect of the temporary beam;

[0031] Figure 2 is the on-site layout schematic diagram of the intelligent control system for the lateral temperature gradient effect of the temporary beam;

[0032] Figure 3 is the schematic diagram of the device system of the intelligent control system for the lateral temperature gradient effect of the temporary beam;

[0033] Figure 4 is the neural network structure diagram of the intelligent control system for the lateral temperature gradient effect of the temporary beam.

[0034] Wherein: 1 - side bracing steel beam, 2 - heat dissipation elastic pad, 3 - excitation device, 4 - temperature sensor, 5 - thermometer, 6 - anemometer, 7 - solar radiation meter, 8 - data acquisition device, 9 - processor, 10 - rubber pad, 11 - jack, 12 - gravity base, 13 - piston device, 14 - support structure, 15 - environmental detection device.

[0035] The present invention adopts the above technical solutions, and the beneficial effects compared with the prior art are as follows:

[0036] 1. The present invention applies eccentric forces at both ends of the temporary beam through the excitation device to form an equivalent bending moment, resisting the bending effect caused by the temperature gradient, and can effectively control the lateral displacement of the structure.

[0037] 2. The present invention supports the temporary beam through the side bracing steel beam and the heat dissipation elastic pad, restricts the lateral bending of the structure while releasing a certain amount of temperature internal force, and can transfer and dissipate part of the heat of the temporary beam, reducing the surface temperature of the structure to a certain extent, which is beneficial to the safety of the structure.

[0038] 3. The present invention introduces a neural network to train the collected data, realizes the real-time monitoring and intelligent control of the temperature gradient effect, and does not require the invocation of human resources.

[0039] 4. The system device provided by the present invention has a simple structure, is easy to install, has a relatively low cost, is easy to maintain, can be remotely controlled through the terminal, and does not require a large number of line connections. Detailed implementation manners

[0040] In order to better understand the technical content of the present invention, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.

[0041] In the present invention, various aspects of the present invention are described with reference to the drawings, and many illustrative embodiments are shown in the drawings. The embodiments of the present invention are not limited to those described in the drawings. It should be understood that the present invention can be implemented by any one of the various concepts and embodiments introduced above, and the concepts and embodiments described in detail below, because the concepts and embodiments disclosed by the present invention are not limited to any embodiment. In addition, some aspects disclosed by the present invention can be used alone, or in any suitable combination with other aspects disclosed by the present invention.

[0042] As Figure 1 shown, for the intelligent regulation system of the lateral temperature gradient effect of the portable beam in the present invention, its principle is: due to sunlight irradiation, the portable beam will bend due to the temperature effect, and an eccentric force is applied at both ends of the portable beam to form an equivalent bending moment to resist the bending effect caused by the temperature gradient.

[0043] As Figure 2 shown, on both sides of the steel rail at the construction site, portable beams are respectively arranged, and the excitation device 3 acts on a pair of eccentric forces at the ends of the portable beam respectively. Each pair of eccentric forces is equal in magnitude and opposite in direction, so as to form a resisting bending moment at both ends of the portable beam to balance the bending effect caused by the temperature gradient. Among them, the thrust facing the portable beam is generated by the jack 11 lifting, and the rubber pad 10 plays a role in distributing the concentrated load, avoiding the adverse effect of local stress concentration on the steel box girder; the tension force facing away from the portable beam is generated by the jack 11 tensioning. The specific tensioning operation is as follows: all the reserved holes have been tied with steel wire ropes and connected to the jack 11, and the jack 11 tensions the steel wire ropes to apply a tension force to the end of the portable beam. The displacement generated during the operation of the excitation device 3 is released by the piston device 13. Four excitation devices 3 need to be configured for a single-sided portable beam.

[0044] As Figure 3Structural diagram of the present invention described above, side support steel beam 1, heat dissipation elastic pad 2, temperature sensor 4, excitation device 3, processor 9; the side support steel beam 1 is respectively pre-buried and anchored in the foundation in advance and arranged on both horizontal sides of the bridge girder. The heat dissipation elastic pad 2 is used to firmly bond the bridge girder where it is located and the side support steel beam 1, and limit the lateral bending of the bridge girder while releasing a certain amount of temperature internal force. The excitation device 3 is attached to both radial ends of the bridge girder where it is located and is connected to the steel wire ropes arranged on the bridge girder. The temperature sensor 4 is placed on the surface of the web of the bridge girder to detect the real-time temperature of the bridge girder and output a signal to the processor 9 connected thereto. The processor 9 is connected to the excitation device 3, receives the signal output from the temperature sensor 4, and uses the trained lateral temperature gradient effect regulation model to control the excitation device 3 connected thereto, applying an eccentric force to the bridge girder where the excitation device is attached to form an equivalent bending moment to resist the bending effect caused by the lateral temperature gradient on the bridge girder. Since the range of sunlight irradiation shifts with time, which will cause the temperature gradient of the bridge girder to change continuously, the processor 9 detects the change trend of the temperature difference between the two sides of the bridge girder caused by the shift of sunlight according to the temperature sensor 4, and controls the excitation device 3 connected thereto to realize the steering of the eccentric force according to the preset threshold of the system. Among them, the excitation device 3 includes a rubber pad 10, a jack 11, a gravity base 12, a piston device 13, and a support structure 14; one end of the support structure 14 is installed on the gravity base 12, and the other end is movably connected to one end of the jack 11 through the piston device 13. The other end of the jack 11 is the rubber pad 10, and the rubber pad 10 is attached to the bridge girder. The jack 11 is used to lift and generate an eccentric pressure facing the bridge girder and a tensile force away from the bridge girder. The rubber pad 10 is used to prevent the bridge girder from deforming due to stress concentration.

[0045] The functions of the side support steel beam 1 and the heat dissipation elastic pad 2 are as follows: Since the internal force of the structure caused by the temperature gradient is non-linearly distributed, the externally applied force cannot completely balance it. The existence of the two can limit the lateral bending of the structure while releasing a certain amount of temperature internal force, which is beneficial to the structural safety. The heat dissipation elastic pad 2 absorbs heat and does not easily heat up, and can transfer and dissipate part of the heat of the bridge girder, reducing the surface temperature of the structure to a certain extent.

[0046] This system further includes an environmental detection device 15. The environmental detection device 15 includes a thermometer 5, an anemometer 6, and a pyranometer 7, which are respectively used to collect the air temperature, wind speed, and maximum solar radiation amount in the area where the bridge girder is located, and obtain the eccentric force according to the following method:

[0047] According to the air temperature, wind speed, and maximum solar radiation amount in the area where the bridge girder is located, further obtain the daily maximum air temperature, daily minimum air temperature, daily average wind speed, and daily maximum solar radiation amount in the area where the bridge girder is located.

[0048] After that, calculate the temperature difference at a distance of x from the surface of the bridge girder according to the following formula:

[0049]

[0050] Among them, α s is the coefficient of linear expansion, T 0 is the temperature variation range in the area where the variable is located.

[0051] U is the daily maximum solar radiation, T max is the daily maximum temperature, T min is the daily minimum temperature, and v is the daily average wind speed.

[0052] Calculate the self-stress generated by the temperature gradient according to the following formula:

[0053] σ(x) = E[α s ·T(x) - (ε 0 + φx)],

[0054] Among them, φ is the cross-section deformation curvature, ε 0 is the strain at the cross-section transverse x = 0,

[0055] Calculate the bending moment value generated by the non-linear temperature distribution according to the following formula:

[0056]

[0057] Among them, E is the elastic modulus; b is the cross-section width, x 0 is the distance from the cross-section end to the centroid axis, h(x) is the cross-section height at x, and I is the cross-section moment of inertia.

[0058] Calculate the eccentric force according to the following formula:

[0059]

[0060] As Figure 4 shown, introduce a neural network to construct and train a lateral temperature gradient effect regulation model for the data collected by the environmental detection device 15, and calculate the temperature gradient effect and the magnitude of the eccentric force of the simply supported beam in real time. The lateral temperature gradient effect regulation model is obtained according to the following steps:

[0061] S11. Based on the temperature, wind speed, and solar radiation of the environment where the simply supported beam is located measured by the environmental detection device 15 placed within the preset range near the simply supported beam, output the detected temperature, wind speed, and solar radiation environmental data to the data acquisition device 8 connected thereto; and output the environmental data to the processor 9.

[0062] S21. Using the daily air temperature, daily wind speed, and daily maximum solar radiation in the area where the beam is located as inputs, and the eccentric force applied to the beam and the temperature gradient corresponding thereto as outputs, construct and train a lateral temperature gradient effect regulation model to obtain the eccentric force applied to the beam and the temperature gradient.

[0063] The processing end 9 is used to realize the automatic adjustment of the eccentric force magnitude by the excitation device 3 and the intelligent monitoring of the temperature gradient effect of the beam.

[0064] Although the present invention has been described above with reference to preferred embodiments, it is not intended to limit the present invention. Those of ordinary skill in the technical field to which the present invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the claims.

Claims

1. An intelligent control system for the lateral temperature gradient effect of a portable beam, characterized in that, it includes side support steel beams (1), heat dissipation elastic pads (2), temperature sensors (4), excitation devices (3), and a processor (9); The side support steel beams (1) are respectively pre-buried and anchored in the foundation and arranged on both horizontal sides of the portable beam. The heat dissipation elastic pads (2) are used to firmly bond the portable beam where they are located and the side support steel beams (1), and limit the lateral bending of the portable beam while releasing a certain amount of temperature internal force; The excitation devices (3) are attached to both radial ends of the portable beam where they are located and are connected to the steel wire ropes arranged on the portable beam; the temperature sensors (4) are placed on the surface of the portable beam web to detect the real-time temperature of the portable beam and output signals to the processor (9) connected to them; The processor (9) is connected to the excitation devices (3). After receiving the signals output from the temperature sensors (4), it uses the trained lateral temperature gradient effect control model to control the excitation devices (3) connected to it, applying eccentric forces to the portable beam where the excitation devices are attached to form equivalent bending moments to resist the bending effect caused by the lateral temperature gradient on the portable beam. At the same time, the processor (9) detects the changing trend of the temperature difference between the two sides of the portable beam caused by the deviation of sunlight according to the temperature sensors (4), and controls the excitation devices (3) connected to it to realize the steering of the eccentric force according to the preset threshold of the system.

2. An intelligent control system for the lateral temperature gradient effect of a portable beam according to claim 1, characterized in that, The excitation device (3) includes a rubber pad (10), a jack (11), a gravity base (12), a piston device (13), and a support structure (14); one end of the support structure (14) is installed on the gravity base (12), and the other end is movably connected to one end of the jack (11) through the piston device (13). The other end of the jack (11) is the rubber pad (10). The rubber pad (10) is attached to the portable beam. The jack (11) is used to lift and generate an eccentric pressure facing the portable beam and a tensile force away from the portable beam. The rubber pad (10) is used to prevent the portable beam from deforming due to stress concentration.

3. An intelligent control system for the lateral temperature gradient effect of a portable beam according to claim 2, characterized in that, The eccentric force is obtained according to the following steps: S1. The environmental detection device (15) collects the air temperature, wind speed, and maximum solar radiation in the area where the portable beam is located through the thermometer (5), anemometer (6), and pyranometer (7) it includes; S2. According to the air temperature, wind speed, and maximum solar radiation in the area where the portable beam is located obtained in step S1, further obtain the daily maximum air temperature, daily minimum air temperature, daily average wind speed, and daily maximum solar radiation in the area where the portable beam is located; S3. Calculate the temperature difference at a distance x from the surface of the portable beam according to the following formula: Among them, α s is the linear expansion coefficient, T 0 is the temperature variation amplitude in the region where the variable is located, U is the daily maximum solar radiation, T max is the daily maximum temperature, T min is the daily minimum temperature, and v is the daily average wind speed; S4. Calculate the self-stress generated by the temperature gradient according to the following formula: σ(x) = E[α s ·T(x) - (ε 0 + φx)], where φ is the cross-section deformation curvature, ε 0 is the strain at the cross-section transverse x = 0, S5. Calculate the bending moment value generated by the non-linear temperature distribution according to the following formula: where E is the elastic modulus; b is the cross-sectional width, x 0 is the distance from the cross-sectional end to the centroidal axis, h(x) is the cross-sectional height at x, and I is the moment of inertia of the cross-section, S6. Calculate the eccentric force according to the following formula:

4. An intelligent control system for the lateral temperature gradient effect of a portable beam according to claim 3, characterized in that, The trained lateral temperature gradient effect control model is obtained according to the following steps: S11. Output the detected temperature, wind speed, and solar radiation environmental data of the environment where the bridging girder is located, which are detected by the environmental detection device (15) placed in the preset range near the bridging girder, to the data acquisition device (8) connected thereto; and output the environmental data to the processor (9); S21. Construct and train a lateral temperature gradient effect regulation model with the daily air temperature, daily wind speed, and daily maximum solar radiation in the area where the bridging girder is located as inputs and the eccentric force applied to the bridging girder corresponding thereto as the output.

5. An intelligent regulation system for the lateral temperature gradient effect of a bridging girder according to claim 2, characterized in that The excitation device (3) acts on the bridging girder with a pair of eccentric forces respectively through the displacement of the piston device (13): a thrust force facing the bridging girder and a pulling force away from the bridging girder. Each pair of eccentric forces is equal in magnitude and opposite in direction. The thrust force facing the bridging girder is generated by the jack (11) lifting, and the pulling force away from the bridging girder is generated by the jack (11) tensioning the steel wire ropes arranged on the bridging girder connected thereto.

6. An intelligent regulation system for the lateral temperature gradient effect of a bridging girder according to claim 1, characterized in that Four excitation devices (3) are arranged to fit at both radial ends of the bridging girder where they are located.

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