Testing device and testing method for monitoring corrosion of steel wire in prestressed reinforced concrete

Abstract

The invention discloses a device and a method for monitoring and testing corrosion of steel wires in prestressed reinforced concrete, and relates to the technical field of prestressed reinforced concrete tests.The device for monitoring and testing corrosion of steel wires in prestressed reinforced concrete comprises a prestressed steel wire tensioning mechanism, a corrosion mechanism and a monitoring mechanism, the prestressed steel wire tensioning mechanism is used for tensioning a steel wire in a concrete test piece to form a prestressed steel wire, the corrosion mechanism comprises a corrosion pool, the corrosion pool is used for containing corrosive liquid and is communicated with the concrete test piece, and the monitoring mechanism comprises an acoustic emission sensor and a distributed optical fiber sensor. The acoustic emission sensor is used for monitoring the state of the prestressed steel wire in a corrosion environment, and the distributed optical fiber sensor is used for collecting corrosion wire breaking signals of the prestressed steel wire and positioning the wire breaking position. The test device and the test method for monitoring the corrosion of the steel wire in the prestressed reinforced concrete can be used for monitoring the corrosion of the steel wire in the prestressed reinforced concrete, and are simple to operate and relatively low in cost.

Description

Technical Field

[0001] The invention relates to the technical field of prestressed reinforced concrete testing, and in particular to a steel wire corrosion monitoring test device and a test method in prestressed reinforced concrete. Background Art

[0002] Prestressed reinforced concrete is a concrete structure that provides additional bearing capacity and deformation resistance after the structure is loaded by pre-stressing the steel bars or cables. This technology enhances the performance of the structure by effectively utilizing the synergy of steel bars and concrete, and is widely used in structures such as bridges and floors.

[0003] The steel wire or cable in prestressed reinforced concrete is the key load-bearing part of the structure. When the steel wire is corroded or broken, it may have a serious impact on the safety and durability of the structure. Corrosion and wire breakage are common diseases of prestressed reinforced concrete, especially in some harsh environments, which are very harmful and cause very significant economic losses.

[0004] The monitoring of steel wire corrosion in prestressed reinforced concrete is of great significance. The corrosion of steel wire not only directly affects the bearing capacity of prestressed reinforced concrete, but may also cause cracks, local failures and even overall structural damage. Therefore, regular and timely monitoring of steel wire corrosion is essential to prevent accidents, extend the service life of the structure and ensure project safety.

[0005] However, wire breakage monitoring using prototype prestressed reinforced concrete is difficult and costly. Summary of the invention

[0006] The purpose of the present invention is to provide a testing device and method for monitoring corrosion of steel wires in prestressed reinforced concrete, so as to solve the problems existing in the above-mentioned prior art and monitor the corrosion of steel wires in prestressed reinforced concrete, which is simple to operate and has low cost.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] The present invention provides a corrosion monitoring test device for steel wires in prestressed reinforced concrete, comprising: a prestressed steel wire tensioning mechanism, a corrosion mechanism and a monitoring mechanism, wherein the prestressed steel wire tensioning mechanism is used to tension the steel wires in a concrete specimen to form prestressed steel wires, the corrosion mechanism comprises a corrosion pool, the corrosion pool is used to contain corrosion liquid, the corrosion pool is connected to the concrete specimen, the monitoring mechanism comprises an acoustic emission sensor and a distributed optical fiber sensor, the acoustic emission sensor is used to monitor the state of the prestressed steel wire in a corrosive environment, and the distributed optical fiber sensor is used to collect a wire break signal of the prestressed steel wire corrosion and locate the wire break position.

[0009] Preferably, the prestressed steel wire tensioning mechanism includes a reaction frame, a movable plate and a tensioning structure, the movable plate is located on one side of the reaction frame, the tensioning structure is located between the movable plate and the reaction frame, a force sensor is provided on the steel wire, one end of the steel wire is detachably connected to the reaction frame, and the other end of the steel wire is detachably connected to the movable plate, the prestress is applied to the steel wire through the tensioning structure, and the force sensor is used to monitor the prestress applied to the steel wire by the tensioning structure.

[0010] Preferably, the reaction frame includes a first fixed plate, a second fixed plate and a plurality of support rods, the first fixed plate and the second fixed plate are arranged opposite to each other, the tensioning structure is located between the first fixed plate and the movable plate, one end of the steel wire is detachably connected to the second fixed plate, the steel wire passes through the first fixed plate, and the support rods pass through the second fixed plate, the first fixed plate and the movable plate in sequence.

[0011] Preferably, it further comprises an elastic element, wherein the elastic element is sleeved on the support rod and the elastic element is located between the first fixed plate and the movable plate.

[0012] Preferably, the corrosion pool is arranged on the concrete specimen, and the corrosion pool and the concrete specimen can be sealed and connected.

[0013] Preferably, a heating structure is provided in the corrosion pool, and the heating structure is used to heat the corrosive liquid in the corrosion pool; the corrosion pool is also connected to an external corrosive liquid storage structure and a corrosive liquid collecting structure, and a water pump is provided on the pipelines connecting the corrosion pool to the corrosive liquid storage structure and the corrosive liquid collecting structure respectively.

[0014] Preferably, there are two acoustic emission sensors, and the two acoustic emission sensors are respectively located above the upper surface of the concrete specimen and below the lower surface of the concrete specimen.

[0015] Preferably, there are two distributed optical fiber sensors, and the two distributed optical fiber sensors are respectively located on the upper surface of the concrete specimen and the lower surface of the concrete specimen.

[0016] Preferably, the acoustic emission sensor is arranged on the concrete specimen through a fixing structure, the fixing structure includes an upper cover and a base, the upper cover and the base are detachably connected, a sealing element is provided at the connection between the upper cover and the base, and the upper cover and the base form a sealed space for placing the acoustic emission sensor.

[0017] The present invention also provides a test method using the steel wire corrosion monitoring test device in prestressed reinforced concrete, comprising the following steps:

[0018] Step 1: fix the two ends of the steel wire on the prestressed steel wire tensioning mechanism respectively, and tension the steel wire;

[0019] Step 2: After the steel wire is tensioned, concrete is poured to form a concrete specimen outside the steel wire;

[0020] Step 3: Install the acoustic emission sensor and the distributed optical fiber sensor, and connect the acoustic emission sensor to the acoustic emission collector, and connect the distributed optical fiber sensor to the optical fiber demodulator;

[0021] Step 4: Install the corrosion mechanism, introduce the corrosion liquid into the corrosion pool, and use the acoustic emission sensor and the distributed optical fiber sensor for monitoring.

[0022] Compared with the prior art, the present invention has achieved the following technical effects:

[0023] The present invention uses an acoustic emission sensor and a distributed optical fiber sensor to monitor the corrosion and broken wire signals of prestressed steel wires in concrete specimens, which can effectively ensure that the prestress of the prestressed steel wires is maintained during the tensioning process, and simulate the state of the prestressed steel wires in concrete under different corrosive environments. The state of the prestressed steel wires in the corrosive environment can be monitored in real time by the acoustic emission sensor, and the corrosion and broken wire signals of the prestressed steel wires can be collected and the broken wire positions can be located by the distributed optical fiber sensor; the present invention can flexibly replace steel wires of different diameters according to the test requirements, which is convenient for studying the broken wire signals of steel wires of different diameters. The present invention is easy to carry, effectively improves the operability of the test, can replace complex prototype tests, and reduce test costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is an axonometric diagram of the steel wire corrosion monitoring test device in prestressed reinforced concrete of the present invention;

[0026] Figure 2 A top view of a test device for monitoring corrosion of steel wires in prestressed reinforced concrete according to the present invention;

[0027] Figure 3 It is an axonometric view of the fixed structure of the present invention;

[0028] Figure 4 It is a schematic diagram of installing the acoustic emission sensor of the present invention;

[0029] Figure 5 A schematic diagram of a base of a fixing structure of the present invention;

[0030] In the figure: 1. anchor, 2. force sensor, 3. nut, 4. concrete specimen, 5. support rod, 6. corrosion tank, 7. movable plate, 8. steel wire, 9. tensioning structure, 10. first fixed plate, 11. fixed structure, 12. distributed optical fiber sensor, 13. second fixed plate, 14. upper cover, 15. base, 16. sealing element, 17. acoustic emission sensor. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The purpose of the present invention is to provide a testing device and method for monitoring corrosion of steel wires in prestressed reinforced concrete, so as to solve the problems existing in the above-mentioned prior art and monitor the corrosion of steel wires in prestressed reinforced concrete, which is simple to operate and has low cost.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Embodiment 1

[0035] like Figures 1 to 5 As shown, this embodiment provides a steel wire corrosion monitoring test device in prestressed reinforced concrete, including: a prestressed steel wire tensioning mechanism, a corrosion mechanism and a monitoring mechanism, the prestressed steel wire tensioning mechanism is used to tension the steel wire 8 in the concrete specimen 4, the corrosion mechanism includes a corrosion pool 6, the corrosion pool 6 is used to hold the corrosive liquid, the corrosion pool 6 is arranged on the concrete specimen 4, the corrosion pool 6 is connected to the concrete specimen 4, and the corrosion pool 6 and the concrete specimen 4 are sealed and connected with epoxy resin glue, so that the concrete specimen 4 only corrodes from the upper surface, the monitoring mechanism includes an acoustic emission sensor 17 and a distributed optical fiber sensor 12, the acoustic emission sensor 17 is used to monitor the state of the prestressed steel wire in the corrosive environment, and the distributed optical fiber sensor 12 is used to collect the prestressed steel wire corrosion broken wire signal and locate the broken wire position.

[0036] In this embodiment, the prestressed steel wire tensioning mechanism includes a reaction frame, a movable plate 7 and a tensioning structure 9. The movable plate 7 is located on one side of the reaction frame. The tensioning structure 9 is a separate hollow jack. The tensioning structure 9 is located between the movable plate 7 and the reaction frame. A force sensor 2 is provided on the steel wire 8. The force sensor 2 is preferably a vibrating string sensor. One end of the steel wire 8 is detachably connected to the reaction frame, and the other end of the steel wire 8 is detachably connected to the movable plate 7. Prestress is applied to the steel wire 8 through the tensioning structure 9. The force sensor 2 is used to monitor the prestress applied to the steel wire 8 by the tensioning structure 9.

[0037] In this embodiment, the reaction frame includes a first fixed plate 10, a second fixed plate 13, an elastic element and a plurality of support rods 5. The first fixed plate 10 and the second fixed plate 13 are arranged opposite to each other. The first fixed plate 10, the second fixed plate 13 and the movable plate 7 are all steel plates. The tensioning structure 9 is located between the first fixed plate 10 and the movable plate 7. One end of the steel wire 8 is fixed to the second fixed plate 13, and the other end of the steel wire 8 is fixed to the movable plate 7 by anchors 1 respectively. The steel wire 8 passes through the first fixed plate 10. The support rod 5 is a screw rod. The support rod 5 passes through the second fixed plate 13, the first fixed plate 10 and the movable plate 7 in turn. The support rod 5 is threadedly connected to the second fixed plate 13 and the first fixed plate 10, and the limiting is achieved by the nut 3. The elastic element is sleeved on the support rod 5, and the elastic element is located between the first fixed plate 10 and the movable plate 7.

[0038] In this embodiment, the corrosion pool 6 is provided with a cover, and a heating structure and a humidifier are provided inside the corrosion pool 6. The heating structure is used to heat the corrosive liquid in the corrosion pool 6; the corrosion pool 6 is also connected to an external corrosive liquid storage structure and a corrosive liquid collecting structure, and a water pump is provided on the pipelines connecting the corrosion pool 6 to the corrosive liquid storage structure and the corrosive liquid collecting structure respectively.

[0039] In this embodiment, the transmitting sensor and the distributed optical fiber sensor 12 monitor the wire breakage phenomenon of the prestressed steel wire in real time; there are two transmitting sensors, and the two acoustic emission sensors 17 are respectively located at the center position above the upper surface of the concrete specimen 4 and the center position below the lower surface of the concrete specimen 4, and the signal collected by the acoustic emission sensor 17 is transmitted to the acoustic emission collector; there are two distributed optical fiber sensors 12, and the two distributed optical fiber sensors 12 are respectively attached to the upper surface of the concrete specimen 4 and the lower surface of the concrete specimen 4 through high-performance adhesives, and the distributed optical fiber sensors 12 are arranged on the plane where the center line of the concrete specimen 4 is located, and the center lines of the two distributed optical fiber sensors 12 and the center line of the steel wire 8 are located in the same vertical plane, and the signals collected by the distributed optical fiber sensors 12 are transmitted to the optical fiber demodulator.

[0040] In this embodiment, the acoustic emission sensor 17 is arranged on the concrete specimen 4 through the fixing structure 11. The fixing structure 11 includes an upper cover 14 and a base 15. The upper cover 14 and the base 15 are connected by screws. A sealing element 16 is arranged at the connection between the upper cover 14 and the base 15. The upper cover 14 and the base 15 form a sealed space for placing the acoustic emission sensor 17. When the concrete specimen 4 is poured, the base 15 is pre-embedded in the surface of the concrete specimen 4, and the lower surface of the base 15 is flush with the surface of the concrete specimen 4. Then, the acoustic emission sensor 17 is installed in the fixing structure 11, and the upper cover 14 is installed and locked with screws.

[0041] This embodiment uses the acoustic emission sensor 17 and the distributed optical fiber sensor 12 to monitor the corrosion and broken wire signals of the prestressed steel wire in the concrete specimen 4, which can effectively ensure that the prestress of the prestressed steel wire is maintained during the tensioning process, and simulate the state of the prestressed steel wire in the concrete under different corrosion environments. The state of the prestressed steel wire in the corrosion environment can be monitored in real time by the acoustic emission sensor 17, and the corrosion and broken wire signals of the prestressed steel wire can be collected and the broken wire position can be located by the distributed optical fiber sensor 12; this embodiment can flexibly replace steel wires 8 of different diameters according to the test requirements, which is convenient for studying the broken wire signals of steel wires 8 of different diameters. This embodiment is easy to carry, effectively improves the operability of the test, can replace complex prototype tests, and reduce test costs.

[0042] This embodiment simulates the real state of prestressed steel wire concrete in a corrosive environment, comprehensively uses two monitoring methods, performs real-time monitoring and feedback on possible wire breakage, and collects different wire breakage signals for analysis, providing a theoretical basis for the detection and research of prestressed steel wire damage.

[0043] Embodiment 2

[0044] This embodiment provides a test method using the steel wire corrosion monitoring test device in prestressed reinforced concrete of embodiment 1, comprising the following steps:

[0045] Step 1, assemble the reaction frame, fix the first fixed plate 10 and the second fixed plate 13, the movable plate 7 can move freely, install the tensioning structure 9, adjust the height of the tensioning structure 9, pass the vibrating wire sensor and the anchor 1 through the steel wire 8, fix the two ends of the steel wire 8 to the second fixed plate 13 and the movable plate 7 through the anchor 1, and tension the steel wire 8 by applying pressure through the tensioning structure 9;

[0046] When the tensioning structure 9 is used to tension the steel wire 8, a graded loading control method is adopted, and the tensioning force is read by a vibrating wire sensor. When each stage is reached, the load is kept constant for 5 minutes until the tensioning is stopped when the predetermined tensioning force is reached;

[0047] Step 2: After the steel wire 8 is tensioned, concrete is poured, and the base 15 of the fixed structure 11 is embedded in the upper surface of the concrete specimen 4 to form the concrete specimen 4 outside the steel wire 8;

[0048] Step 3: After the concrete specimen 4 is cured, a distributed optical fiber sensor 12 is installed on the surface of the concrete specimen 4, and then an acoustic emission sensor 17 is installed, and the acoustic emission sensor 17 is connected to the acoustic emission collector, and the distributed optical fiber sensor 12 is connected to the optical fiber demodulator;

[0049] Step 4, install the corrosion pool 6 on the upper surface of the concrete specimen 4, and do waterproofing, pass the corrosion liquid into the corrosion pool 6, and use the acoustic emission sensor 17 and the distributed optical fiber sensor 12 to monitor. During the wire break monitoring process, when a wire breaks, the broken wire will quickly release energy and generate transient elastic waves. These elastic waves will propagate along the inside of the component and be received by the acoustic emission sensor 17 and the distributed optical fiber sensor 12 installed on the concrete specimen 4. The acoustic emission sensor 17 and the distributed optical fiber sensor 12 convert the received signal into an electrical signal and transmit it to the acoustic emission collector and the optical fiber demodulator. The acoustic emission collector and the optical fiber demodulator will process and analyze the received signal to extract an effective wire break signal. The wire break signal contains information such as the position of the broken wire and the energy generated by the broken wire. The various data of the concrete specimen 4 are tested and recorded. After the test, the corrosion liquid in the corrosion pool 6 is discharged.

[0050] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. The test device for monitoring corrosion of steel wire in prestressed reinforced concrete is characterized by: include: A prestressed steel wire tensioning mechanism, a corrosion mechanism and a monitoring mechanism, wherein the prestressed steel wire tensioning mechanism is used to tension the steel wires in a concrete specimen to form prestressed steel wires, the corrosion mechanism includes a corrosion pool, the corrosion pool is used to contain a corrosive liquid, the corrosion pool is connected to the concrete specimen, the monitoring mechanism includes an acoustic emission sensor and a distributed optical fiber sensor, the acoustic emission sensor is used to monitor the state of the prestressed steel wire in a corrosive environment, and the distributed optical fiber sensor is used to collect the prestressed steel wire corrosion broken wire signal and locate the broken wire position.

2. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1 is characterized by: The prestressed steel wire tensioning mechanism includes a reaction frame, a movable plate and a tensioning structure, wherein the movable plate is located on one side of the reaction frame, and the tensioning structure is located between the movable plate and the reaction frame. A force sensor is provided on the steel wire, one end of the steel wire is detachably connected to the reaction frame, and the other end of the steel wire is detachably connected to the movable plate. Prestress is applied to the steel wire through the tensioning structure, and the force sensor is used to monitor the prestress applied to the steel wire by the tensioning structure.

3. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 2 is characterized by: The reaction frame includes a first fixed plate, a second fixed plate and a plurality of support rods, the first fixed plate and the second fixed plate are arranged opposite to each other, the tensioning structure is located between the first fixed plate and the movable plate, one end of the steel wire is detachably connected to the second fixed plate, the steel wire passes through the first fixed plate, and the support rods pass through the second fixed plate, the first fixed plate and the movable plate in sequence.

4. The corrosion monitoring test device for steel wire in prestressed reinforced concrete according to claim 3 is characterized by: It also includes an elastic element, which is sleeved on the support rod and located between the first fixed plate and the movable plate.

5. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1 is characterized by: The corrosion pool is arranged on the concrete specimen, and the corrosion pool and the concrete specimen can be sealed and connected.

6. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1 is characterized by: A heating structure is provided in the corrosion pool, and the heating structure is used to heat the corrosive liquid in the corrosion pool; the corrosion pool is also connected to an external corrosive liquid storage structure and a corrosive liquid collection structure, and a water pump is provided on the pipelines connecting the corrosion pool to the corrosive liquid storage structure and the corrosive liquid collection structure respectively.

7. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1 is characterized by: There are two acoustic emission sensors, and the two acoustic emission sensors are respectively located above the upper surface of the concrete specimen and below the lower surface of the concrete specimen.

8. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1 is characterized by: There are two distributed optical fiber sensors, and the two distributed optical fiber sensors are respectively located on the upper surface of the concrete specimen and the lower surface of the concrete specimen.

9. The steel wire corrosion monitoring test device in prestressed reinforced concrete according to claim 1, characterized in that: The acoustic emission sensor is arranged on the concrete specimen through a fixing structure, wherein the fixing structure comprises an upper cover and a base, wherein the upper cover and the base are detachably connected, a sealing element is arranged at the connection between the upper cover and the base, and the upper cover and the base form a sealed space for placing the acoustic emission sensor.

10. A test method using the steel wire corrosion monitoring test device in prestressed reinforced concrete according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: fix the two ends of the steel wire on the prestressed steel wire tensioning mechanism respectively, and tension the steel wire; Step 2: After the steel wire is tensioned, concrete is poured to form a concrete specimen outside the steel wire; Step 3: Install the acoustic emission sensor and the distributed optical fiber sensor, and connect the acoustic emission sensor to the acoustic emission collector, and connect the distributed optical fiber sensor to the optical fiber demodulator; Step 4: Install the corrosion mechanism, introduce the corrosion liquid into the corrosion pool, and use acoustic emission sensors and distributed optical fiber sensors for monitoring.

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