Bridge wet joint concrete performance test system and test method

Abstract

The application discloses a bridge wet joint concrete performance test system and a test method. The bridge wet joint concrete performance test system comprises a concrete pouring mold, a mold fixing unit and a vibration isolation unit. The concrete pouring mold comprises a plurality of splicing units, the plurality of splicing units are detachably spliced to form a groove body; a plurality of first partitions are detachably connected with the groove body, and the plurality of first partitions separate a first pouring bin, a second pouring bin and a third pouring bin; the mold fixing unit comprises a fixing plate and an end support frame, the fixing plate is connected with the first pouring bin, and the end support frame is connected with the third pouring bin; and the vibration isolation unit comprises a plurality of vibration isolation devices, and the plurality of vibration isolation devices are arranged between the first pouring bin and the second pouring bin and between the second pouring bin and the third pouring bin. The application can accurately reproduce the dynamic response characteristics of one side vibration and one side static, has high flexibility and expandability, and can realize a stiffness dynamic adjustment mechanism.

Description

Technical Field

[0001] This invention relates to the field of bridge engineering technology, specifically to a test system and method for testing the performance of wet joint concrete in bridges. Background Technology

[0002] With the increasing demand for transportation, bridge widening has become a common renovation and expansion scheme. However, under the condition of not interrupting traffic, the newly poured concrete of the widened bridge is subjected to cyclic tensile-shear combined action due to the vehicle-bridge coupling vibration caused by vehicle load, which seriously affects the mechanical properties of the joint. This is a research problem that urgently needs to be solved in the construction of bridge widening.

[0003] Currently, experimental research commonly uses shaking tables to simulate vehicle-bridge coupled vibration. While this method can reproduce the impact of vehicle loads on bridge structures in a laboratory environment, it has significant technical limitations, mainly in the following two aspects: First, existing experimental systems use a holistic synchronous vibration loading method, which makes it difficult to accurately reproduce the complex boundary conditions of "differential vibration between old and new bridges" in actual engineering projects. Specifically, existing bridges exhibit dynamic responses under vehicle loads, while newly built, widened bridges are in a quasi-static state. This asymmetric vibration characteristic leads to dynamic stress concentration at the joint interface, but existing equipment lacks the ability to independently control the vibration of the structures on both sides of the wet joint, making it impossible to construct a realistic differential vibration coupling boundary.

[0004] Secondly, existing vehicle-bridge coupled testing systems have functional limitations. On the one hand, due to structural constraints of the testing equipment, it is impossible to simultaneously conduct standard specimen tests in the wet joint area, including tests for benchmark mechanical parameters required by specifications, such as cubic compressive strength and bond strength between new and old concrete. This makes it difficult to accurately characterize the quantitative impact of vibration loads on the strength degradation of wet joints. On the other hand, because the vibration isolation unit lacks a dynamic stiffness adjustment mechanism, it cannot simulate the differences in vibration transmission characteristics between new and old main beams caused by different bridge structures (such as T-beams and box girders) or wet joint construction techniques (different temporary supports, different rebar installation methods). This makes it difficult for the test results to reflect the spatiotemporal non-uniformity of vibration energy transmission in actual engineering. This dual functional deficiency severely restricts the reliability of joint performance evaluation.

[0005] In summary, existing vehicle-bridge coupling tests have technical limitations and functional limitations. Summary of the Invention

[0006] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a test system and method for testing the performance of wet joint concrete in bridges, thereby solving the technical problems of technical and functional limitations in the prior art.

[0007] To achieve the above-mentioned technical objectives, this application adopts the following technical solution: In one aspect, this application provides a concrete performance testing system for wet joints of bridges, including a concrete pouring mold, a mold fixing unit, and a vibration reduction and isolation unit.

[0008] A concrete pouring mold, comprising multiple splicing units and multiple first partitions, wherein the multiple splicing units are detachably spliced ​​together to form a trough, and the multiple first partitions are detachably connected to the trough to divide the trough into at least a first pouring compartment, a second pouring compartment and a third pouring compartment arranged in sequence. A mold fixing unit, comprising a fixing plate and an end support frame, wherein the fixing plate is connected to the first casting chamber and the end support frame is connected to the third casting chamber; The vibration reduction and isolation unit includes multiple vibration isolation devices, which are respectively disposed between the first pouring chamber and the second pouring chamber, and between the second pouring chamber and the third pouring chamber.

[0009] In some embodiments of this application, the mold fixing unit further includes fixing bolts, the fixing plate includes a flange plate, and the first casting chamber is fixedly connected to the flange plate by the fixing bolts.

[0010] In some embodiments of this application, the end support frame includes a threaded rod and a guide sleeve, the guide sleeve being sleeved on the outside of the threaded rod, and the threaded rod being connected to the third casting chamber.

[0011] In some embodiments of this application, the first pouring chamber and the third pouring chamber each have splicing protrusions on the side facing the second pouring chamber, and the second pouring chamber has splicing grooves on both sides, with the splicing protrusions embedded in the splicing grooves.

[0012] In some embodiments of this application, the vibration isolation device includes an electromagnetic coil, a permanent magnet, an iron core, and a vibration isolation controller. The electromagnetic coil is sleeved on the outside of the iron core and located in the vertical gap between the splicing protrusion and the splicing groove. The two poles of the permanent magnet are located on opposite sides of the iron core in the horizontal direction. The vibration isolation controller is electrically connected to the electromagnetic coil.

[0013] In some embodiments of this application, the vibration reduction and isolation unit further includes a host computer, which is signal-connected to the vibration isolation controller.

[0014] In some embodiments of this application, the vibration damping and isolation unit further includes an elastic waterproof component that fills the horizontal gap between the splicing protrusion and the splicing groove.

[0015] In some embodiments of this application, a vibration recorder and at least one vibration measuring instrument are also included, the vibration measuring instrument being installed below the second pouring chamber and signal-connected to the vibration recorder.

[0016] In some embodiments of this application, a plurality of second partitions are further included, which are detachably connected to the trough to divide the second casting chamber into a plurality of sub-casting chambers arranged in sequence, and a vibration measuring instrument is installed below each of the sub-casting chambers.

[0017] Secondly, this application also provides a method for testing the performance of wet-joint concrete in bridges, employing the bridge wet-joint concrete performance testing system as described in any embodiment of the first aspect, comprising the following steps: A groove of a preset size is formed by installing and disassembling the splicing units; The standard test block test and the interface adhesion test were switched by installing and removing the first partition. The vibration boundary between the old and new bridges was simulated using vibration reduction and isolation units; Simultaneously measure vibration parameters and concrete strength to establish a vibration-performance correlation model.

[0018] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include: This application connects to the first and third pouring sections via mold fixing units, accurately reproducing the dynamic response characteristics of a wet joint where one side vibrates and the other side remains stationary under vehicle-bridge coupled vibration during bridge widening projects. This ensures high consistency between experimental results and actual engineering conditions, enhancing the representativeness and application value of the experimental data. The modular splicing units provide high flexibility and scalability, adapting to the testing needs of bridge joints of different types and sizes, enabling standard specimen testing, and meeting the requirements of various experimental scenarios. It allows for a quantitative description of the impact of vibration on newly poured concrete at wet joints. The vibration reduction and isolation units enable a dynamic stiffness adjustment mechanism, simulating the differences in vibration transmission characteristics between the old and new main beams caused by different bridge widening methods and wet joint treatments. This allows for a comprehensive analysis of the mechanical behavior and durability of the joint under different traffic loads. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the embodiments will be briefly described below: Figure 1 This is a schematic diagram of the structure of a bridge wet joint concrete performance testing system according to an embodiment of this application; Figure 2 yes Figure 1 Enlarged schematic diagram of the vibration isolation device.

[0020] Figure label: Concrete pouring mold 1, first partition 11, first pouring chamber 1a, second pouring chamber 1b, third pouring chamber 1c, second partition 12; 2. Fixing plate; 3. End support frame; 4. Vibration isolation device; 41. Electromagnetic coil; 42. Permanent magnet; 43. Iron core; 44. Vibration isolation controller; 5. Fixing bolt; 6. Elastic waterproof component; 7. Vibration recorder; 8. Vibration measuring instrument. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0022] Those skilled in the art will understand that, in this specification, the term "comprising" is an open-ended expression, meaning that the stated feature is present but other features are excluded. Directional terms such as "upper," "lower," "left," and "right" refer to exemplary directions based on the accompanying drawings. Features specified as "first" or "second" implicitly include one or more of that feature. Singular expressions can also be used in plural forms. "Multiple" means two or more. The terms "installed," "connected," and "linked" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection via an intermediate medium, and it can be a connection within two components. Furthermore, "linked" can include wireless connections.

[0023] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a test system and method for testing the performance of wet joint concrete in bridges, thereby solving the technical problems of technical and functional limitations in the prior art.

[0024] To achieve the above-mentioned technical objectives, this application adopts the following technical solution: like Figure 1 and Figure 2 As shown. In a first aspect, this application provides a concrete performance testing system for wet joints of bridges, including a concrete pouring mold 1, a mold fixing unit, and a vibration reduction and isolation unit.

[0025] The concrete casting mold 1 includes multiple splicing units and multiple first partitions 11. The splicing units are detachably spliced ​​together to form a trough. The multiple first partitions 11 are detachably connected to the trough to divide the trough into at least three sequentially arranged casting chambers: a first casting chamber 1a, a second casting chamber 1b, and a third casting chamber 1c. These three casting chambers simulate different areas of the wet joint during bridge widening. The first casting chamber 1a represents the existing old bridge section, the third casting chamber 1c represents the new bridge section on the other side, and the second casting chamber 1b is the wet joint area between the two. Concrete is poured on the simulated static and vibrating sides, and new concrete is poured in the middle wet joint area. The modular design of the mold allows for easy adjustment of the size and relative position of each chamber to adapt to different test conditions. After the concrete reaches a certain strength, a vibration test is conducted, data is collected, and the mechanical behavior and durability of the new concrete in the wet joint area under coupled vibration are analyzed.

[0026] The mold fixing unit includes a fixing plate 2 and an end support frame 3. The fixing plate 2 is connected to the first casting chamber 1a, and the end support frame 3 is connected to the third casting chamber 1c. The first and third casting chambers 1c are fixed to different support structures (fixing plate 2 and end support frame 3). In actual tests, vibration excitation devices (such as vibrators) are installed in specific casting chambers (e.g., the bridge deck section simulating vehicle load). Vibrations of specific frequencies and amplitudes are applied to simulate bridge deck vibration caused by vehicle loads. When vibration is applied to one or more casting chambers, due to the difference in fixing methods, a state of "one side vibrating, one side relatively stationary" can be simulated. For example, the third casting chamber 1c can be fixed, and vibration can be applied only to the first casting chamber 1a, or vice versa. Sensors (such as accelerometers and strain gauges) are arranged in each casting chamber (especially in the wet joint area) to monitor and record vibration response data in real time.

[0027] The vibration reduction and isolation unit includes multiple vibration isolation devices 4, which are respectively disposed between the first casting chamber 1a and the second casting chamber 1b, and between the second casting chamber 1b and the third casting chamber 1c. On the one hand, it allows vibration to be transmitted to the wet joint area (second casting chamber 1b) and then to the stationary side (e.g., third casting chamber 1c) when vibration is applied to the vibrating side (e.g., the first casting chamber 1a). On the other hand, the transmission of vibration from the vibrating side to the stationary side can be controlled or isolated by adjusting the stiffness or damping characteristics of the vibration isolation devices 4. This accurately simulates the complex situation of vibration transmission and attenuation in the structure of an actual bridge due to factors such as the connection between new and old structures, stiffness differences, and different support conditions.

[0028] This application connects to the first pouring chamber 1a and the third pouring chamber 1c via mold fixing units, enabling precise reproduction of the dynamic response characteristics of a wet joint under vehicle-bridge coupled vibration in bridge widening projects, where one side vibrates and the other side remains stationary. This ensures high consistency between experimental results and actual engineering conditions, enhancing the representativeness and application value of the experimental data. The modular splicing units provide high flexibility and scalability, adapting to the testing needs of bridge joints of different types and sizes, and enabling standard specimen testing to meet the requirements of various experimental scenarios. It allows for a quantitative description of the impact of vibration on newly poured concrete in wet joints. The vibration reduction and isolation units enable a dynamic stiffness adjustment mechanism, simulating the differences in vibration transmission characteristics between the old and new main beams caused by different bridge widening methods and wet joint treatments. This allows for a comprehensive analysis of the mechanical behavior and durability of the joint under different traffic loads.

[0029] In some embodiments of this application, the mold fixing unit further includes fixing bolts 5, the fixing plate 2 includes a flange plate, and the first casting chamber 1a is fixedly connected to the flange plate by the fixing bolts 5.

[0030] External vibration sources, such as independent vibration tables and exciters, act on the fixed plate 2 and flange structure, transmitting the vibration to the first pouring chamber 1a via fixing bolts 5, thus simulating the vibration state of the old bridge under traffic load. The tightness of the bolts affects the connection stiffness and damping between the first pouring chamber 1a and the fixed plate 2, thereby affecting the efficiency and characteristics of vibration transmission. Fixed in this way, the first pouring chamber 1a vibrates relative to the second and third pouring chambers 1c.

[0031] This connection method can accurately simulate the vibration state of the old bridge structure in reality. The flange plate provides a large contact area, which helps to disperse the stress of the bolts and improve the stability of the connection. By adjusting the tightening torque of the fixing bolts 5, the connection stiffness between the first pouring chamber 1a and the fixing plate 2 can be adjusted within a certain range.

[0032] In some embodiments of this application, the end support frame 3 includes a threaded rod and a guide sleeve, the guide sleeve being sleeved on the outside of the threaded rod, and the threaded rod being connected to the third casting chamber 1c.

[0033] When the guide sleeve is fixed, the threaded rod can be moved up and down inside the guide sleeve by rotating it. The guide sleeve not only provides thread engagement but also acts as a guide, ensuring that the threaded rod can move up and down smoothly and linearly during rotation, preventing it from wobbling or deviating, and ensuring the stability and accuracy of the support.

[0034] Because the threaded rod is connected to the third casting chamber 1c, the up-and-down movement of the threaded rod directly changes the height of the third casting chamber 1c relative to the supporting foundation. There may be a height difference between the old and new beams, or it may be necessary to simulate specific construction or stress conditions. The adjustable height allows the mold to adapt to these different initial conditions or simulation requirements without replacing the entire supporting structure.

[0035] In some embodiments of this application, the first casting chamber 1a and the third casting chamber 1c both have splicing protrusions on the side facing the second casting chamber 1b, and the second casting chamber 1b has splicing grooves on both sides, with the splicing protrusions embedded in the splicing grooves.

[0036] By adjusting their positions, the splicing protrusions on the first and third casting chambers 1c can be precisely embedded into the splicing grooves on both sides of the second casting chamber 1b. This embedding process serves to position and initially fix the parts.

[0037] It can better maintain the overall stability of the mold during concrete pouring and testing, reducing deformation. It can effectively prevent concrete from leaking from the joints during pouring, ensuring the pouring quality of wet joint concrete.

[0038] In another alternative, the positions of the splicing protrusions and splicing slots are interchanged; that is, the first casting chamber 1a and the third casting chamber 1c have splicing slots, while the second casting chamber 1b has splicing protrusions. During mold assembly, the splicing protrusions of the second casting chamber 1b are aligned and embedded into the splicing slots of the first casting chamber 1a and the third casting chamber 1c. This method also achieves the connection and positioning of the three casting chambers in the width direction.

[0039] In some embodiments of this application, the vibration isolation device 4 includes an electromagnetic coil 41, a permanent magnet 42, an iron core 43, and a vibration isolation controller 44. The electromagnetic coil 41 is sleeved on the outside of the iron core 43 and located in the vertical gap between the splicing protrusion and the splicing groove. The two poles of the permanent magnet 42 are respectively located on opposite sides of the iron core 43 in the horizontal direction. The vibration isolation controller 44 is electrically connected to the electromagnetic coil 41.

[0040] When the electromagnetic coil 41 is energized, it generates a magnetic field. The iron core 43 provides a magnetic flux loop, enhances the magnetic field effect, and serves as a supporting structure for the coil. The permanent magnet 42 provides a constant magnetic field. Its two poles are located on opposite sides of the iron core 43 in the horizontal direction, generating a horizontal magnetic field that interacts with the magnetic circuit formed by the iron core 43. The vibration isolation controller 44 is responsible for monitoring vibration and controlling the current of the electromagnetic coil 41. This vibration isolation device 4 acts directly on the contact interface connecting the two casting chambers (through protrusions and grooves) and mainly controls vertical vibration.

[0041] The permanent magnet 42 generates a constant magnetic field, which interacts with the iron core 43 to form an initial magnetic field environment in the gap. When the electromagnetic coil 41 is not energized, there is an initial elastic or repulsive force generated by the permanent magnet 42, pressing the bump against the groove or maintaining a certain distance from it. When the axle coupling vibration is transmitted to the mold, it will cause the first casting chamber 1a to vibrate relative to the second casting chamber 1b. This vibration will attempt to be transmitted through the contact surface between the bump and the groove. The vibration isolation controller 44 needs to monitor the vibration signal in real time and calculate the magnitude and direction of the electromagnetic force to be applied based on the monitored vibration signal to counteract or reduce the vibration transmission. The controller outputs a corresponding current to the electromagnetic coil 41. The current generates a changing magnetic field, which interacts with the constant magnetic field of the permanent magnet 42 and the relative magnetic field change caused by possible vibration displacement. The magnetic field generated by the electromagnetic coil 41 interacts with the magnetic field of the permanent magnet 42, generating a dynamic force in the vertical gap. This force can be precisely adjusted in magnitude and direction. This dynamic force is used to actively "counteract" or "absorb" the vertical vibration energy that attempts to be transmitted through the bump and the groove. This effectively reduces the extent to which vibration is transmitted from one casting chamber to the other.

[0042] In some embodiments of this application, the vibration reduction and isolation unit further includes a host computer, which is signal-connected to the vibration isolation controller 44.

[0043] The host computer can receive data from the sensors and the vibration isolation controller 44 itself. The host computer sends calculated and optimized control commands to the vibration isolation controller 44. The vibration isolation controller 44 receives the commands from the host computer, generates specific drive signals, and controls the electromagnetic coil 41 to generate corresponding electromagnetic force to achieve the vibration isolation effect.

[0044] In some embodiments of this application, the vibration damping and isolation unit further includes an elastic waterproof component 6, which fills the gap between the splicing protrusion and the splicing groove in the horizontal direction.

[0045] The elastic waterproof component 6 can be made of rubber waterstop. It effectively prevents concrete grout leakage, avoiding defects such as honeycomb and pitting caused by leakage, thus ensuring the structural integrity and mechanical properties of the specimen. It prevents concrete grout from seeping into the joints, facilitating mold disassembly and cleaning, and extending the mold's service life. The elastic component can absorb some impact and vibration, contributing to the overall stability of the mold and reducing noise; the auxiliary buffer complements the active vibration damping unit.

[0046] In some embodiments of this application, a vibration recorder 7 and at least one vibration measuring instrument 8 are also included, the vibration measuring instrument 8 being installed below the second casting chamber 1b and signal-connected to the vibration recorder 7.

[0047] The vibration measuring instrument 8 includes an acceleration sensor, a velocity sensor, or a displacement sensor. Vibration is transmitted through the concrete to the bottom of the second pouring chamber 1b. The vibration below the second pouring chamber 1b includes vibrations from the old and new main beams (the first and third pouring chambers 1c), as well as vibration information transmitted from the deformation of the wet joint itself. The vibration measuring instrument 8 detects these mechanical vibrations (changes in acceleration, velocity, or displacement) and converts them into corresponding electrical signals (voltage or current signals). These electrical signals are transmitted to the vibration recorder 7 via wires.

[0048] This system can accurately measure and record the vibration response of the wet joint area (below the second pouring section 1b) under vehicle loads. By analyzing the recorded vibration data, the stiffness, damping characteristics, and vibration transmission efficiency of the wet joint under different load conditions can be evaluated. Comparing the experimentally measured vibration data with theoretical calculations or finite element simulation results can verify the effectiveness of this test system in simulating the mechanical behavior of the wet joint under vehicle-bridge coupled vibration. By comparing the differences in vibration response under different wet joint treatment methods or different splicing forms, data support can be provided for optimizing the design parameters (such as reinforcement layout, concrete mix proportion, prestressing, etc.) and construction techniques of the wet joint.

[0049] In some embodiments of this application, a plurality of second partitions 12 are further included, which are detachably connected to the trough body to divide the second casting chamber 1b into a plurality of sub-casting chambers arranged in sequence, and a vibration measuring instrument 8 is installed below each sub-casting chamber.

[0050] The second partition 12 is connected to the external trough (which constitutes the main body of the second casting chamber 1b) via bolts, clips, and plugs. This horizontally divides the originally single second casting chamber 1b into multiple independent small areas, i.e., multiple sub-casting chambers. The number of vibration sensors is equal to the number of sub-casting chambers.

[0051] When an external load (such as a simulated vehicle) is applied to the mold, vibrations are transmitted throughout the entire structure, including each sub-casting chamber. Vibration measuring instruments 8 installed below each sub-casting chamber independently detect and convert the vibration signals below that area.

[0052] Each sub-casting chamber is equipped with a vibration measuring instrument 8, enabling distributed, multi-point measurement of the vibration response in the wet joint area. In actual stress conditions, the stress state and vibration response of bridge wet joints at different locations are often non-uniform. This design allows the mold to better simulate this non-uniformity, resulting in research results that are closer to reality.

[0053] Secondly, this application also provides a method for testing the performance of wet-joint concrete in bridges, employing the bridge wet-joint concrete performance testing system as described in any embodiment of the first aspect, comprising the following steps: A groove of a preset size is formed by installing and disassembling the splicing units; The standard test block test and the interface adhesion test are switched by installing and removing the first partition 11; The vibration boundary between the old and new bridges was simulated using vibration reduction and isolation units; Simultaneously measure vibration parameters and concrete strength to establish a vibration-performance correlation model.

[0054] The implementation method of the multi-functional mold for on-site testing of wet joint cast-in-place concrete under vehicle-bridge coupled vibration environment is as follows: The first pouring chamber 1a is anchored to the bridge flange plate by fixing bolts 5. Concrete molding test blocks are placed in the first pouring chamber 1a to simulate the old bridge.

[0055] The second pouring chamber 1b is connected to the first pouring chamber 1a via an electromagnetic vibration isolation device 4. The electromagnetic vibration isolation device 4 can be adjusted in terms of its vibration isolation stiffness by a vibration isolation controller to simulate the different vibration transmission stiffness under different wet joint construction measures. At the same time, freshly mixed concrete is poured into the second pouring chamber 1b.

[0056] The second pouring chamber 1b and the third pouring chamber 1c are connected by an electromagnetic vibration isolation device 4. A concrete molding test block is placed in the third pouring chamber 1c. Below the third pouring chamber 1c is an end support frame 3, which supports the third pouring chamber 1c to form a stable and vibration-free structure. The electromagnetic vibration isolation device 4 can adjust its stiffness by controlling the number of coil turns and the current, thereby achieving different vibration isolation effects.

[0057] The first pouring chamber 1a, the second pouring chamber 1b, and the third pouring chamber 1c are separated by rubber waterstops, which can achieve vibration isolation and prevent the loss of newly poured concrete.

[0058] The removable first partition 11 is used to achieve different test requirements. When the removable first partition 11 is installed, each sub-concrete compartment in the second pouring compartment 1b is an individually molded test block, and standard experimental parameters such as compressive strength can be measured on the test blocks in the second pouring compartment 1b. When the removable first partition 11 is removed, the second pouring compartment 1b is connected to the first pouring compartment 1a and the third pouring compartment 1c, and the aforementioned freshly mixed concrete and the molded concrete test blocks can form a bonding surface between the old and new concrete, realizing the strength test of the bonding surface between the old and new concrete.

[0059] Each sub-casting chamber is equipped with a vibration measuring instrument 8, which is connected to a vibration measurement data recorder. Vibration measurement includes the measurement of key vibration parameters such as vibration acceleration and amplitude.

[0060] By analyzing the strength of each test block in the second pouring chamber 1b obtained above, and their corresponding vibration parameters, the linear relationship between vibration and concrete strength can be obtained, which can be used to guide the construction of wet joint concrete.

[0061] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include: This application connects to the first pouring chamber 1a and the third pouring chamber 1c via mold fixing units, enabling precise reproduction of the dynamic response characteristics of a wet joint under vehicle-bridge coupled vibration in bridge widening projects, where one side vibrates and the other side remains stationary. This ensures high consistency between experimental results and actual engineering conditions, enhancing the representativeness and application value of the experimental data. The modular splicing units provide high flexibility and scalability, adapting to the testing needs of bridge joints of different types and sizes, and enabling standard specimen testing to meet the requirements of various experimental scenarios. It allows for a quantitative description of the impact of vibration on newly poured concrete in wet joints. The vibration reduction and isolation units enable a dynamic stiffness adjustment mechanism, simulating the differences in vibration transmission characteristics between the old and new main beams caused by different bridge widening methods and wet joint treatments. This allows for a comprehensive analysis of the mechanical behavior and durability of the joint under different traffic loads.

[0062] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, processes, and procedures discussed in this application can be alternated, modified, rearranged, decomposed, combined, or deleted.

[0063] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of the claims of this application.

Claims

1. A test system for the performance of wet joint concrete in bridges, characterized in that, include: A concrete pouring mold includes multiple splicing units and multiple first partitions. The multiple splicing units are detachably spliced ​​together to form a trough. The multiple first partitions are detachably connected to the trough to divide the trough into at least three sequentially arranged pouring sections: a first pouring section, a second pouring section, and a third pouring section. The first pouring section represents the existing old bridge section, the third pouring section represents the new bridge section on the other side, and the second pouring section is the wet joint area between the two. When vibration is applied to the first pouring section, due to the difference in fixing method, a state of "one side vibrates, the other side is relatively stationary" can be simulated. The first pouring section is the vibrating side, and the third pouring section is the stationary side. A mold fixing unit, comprising a fixing plate and an end support frame, wherein the fixing plate is connected to the first casting chamber and the end support frame is connected to the third casting chamber; The vibration reduction and isolation unit includes multiple vibration isolation devices, which are respectively disposed between the first casting chamber and the second casting chamber and between the second casting chamber and the third casting chamber; The mold fixing unit further includes fixing bolts, and the fixing plate includes a flange plate. The first casting chamber is fixedly connected to the flange plate by the fixing bolts. An external vibration source acts on the fixed plate and the flange plate, and transmits the vibration to the first pouring chamber through the fixing bolts, thereby simulating the vibration state of the old bridge under traffic load. Both the first and third pouring chambers have splicing protrusions on the side facing the second pouring chamber, and the second pouring chamber has splicing grooves on both sides, with the splicing protrusions embedded in the splicing grooves; The vibration isolation device includes an electromagnetic coil, a permanent magnet, an iron core, and a vibration isolation controller. The electromagnetic coil is sleeved on the outside of the iron core and located in the vertical gap between the splicing protrusion and the splicing groove. The two poles of the permanent magnet are located on opposite sides of the iron core in the horizontal direction. The vibration isolation controller is electrically connected to the electromagnetic coil. The vibration isolation controller monitors vibration and controls the current of the electromagnetic coil; the vibration isolation controller monitors vibration signals in real time, and calculates the magnitude and direction of the electromagnetic force to be applied based on the monitored vibration signals, so as to counteract or reduce vibration transmission; the vibration isolation controller outputs a corresponding current to the electromagnetic coil, and the current generates a changing magnetic field; the magnetic field generated by the electromagnetic coil interacts with the magnetic field of the permanent magnet, generating a dynamic force in the vertical gap; This dynamic force is used to actively "counter" or "absorb" the vertical vibrational energy that attempts to be transmitted through the bumps and slots; It also includes a vibration recorder and at least one vibration measuring instrument, the vibration measuring instrument being installed below the second pouring chamber and connected to the vibration recorder via signal.

2. The bridge wet joint concrete performance testing system according to claim 1, characterized in that, The end support frame includes a threaded rod and a guide sleeve. The guide sleeve is sleeved on the outside of the threaded rod, and the threaded rod is connected to the third casting chamber.

3. The bridge wet joint concrete performance testing system according to claim 1, characterized in that, The vibration reduction and isolation unit also includes a host computer, which is connected to the vibration isolation controller via signal connection.

4. The bridge wet joint concrete performance testing system according to claim 1, characterized in that, The vibration damping and isolation unit also includes an elastic waterproof component, which fills the horizontal gap between the splicing protrusion and the splicing groove.

5. The bridge wet joint concrete performance testing system according to claim 1, characterized in that, It also includes multiple second partitions, which are detachably connected to the trough to divide the second casting chamber into multiple sub-casting chambers arranged in sequence, and a vibration measuring instrument is installed below each sub-casting chamber.

6. A test method for the performance of wet-joint concrete in bridges, characterized in that, The bridge wet joint concrete performance testing system as described in any one of claims 1 to 5 includes the following steps: A groove of a preset size is formed by installing and disassembling the splicing units; The standard test block test and the interface adhesion test were switched by installing and removing the first partition. The vibration boundary between the old and new bridges was simulated using vibration reduction and isolation units; Simultaneously measure vibration parameters and concrete strength to establish a vibration-performance correlation model.

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