Concrete dry-wet state and freeze-thaw cycle coupling test device

Abstract

The utility model discloses a concrete dry-wet state and freeze-thaw cycle coupling test device which comprises an automatic concrete dry-wet control system, a freeze-thaw cycle box and a freeze-thaw cycle testing machine, during testing, a concrete sample is placed in the freeze-thaw cycle box, and then the whole is placed in the freeze-thaw cycle testing machine; the dry and wet state of the concrete is adjusted by the automatic dry and wet control system, and a freeze-thaw cycle test is carried out through the freeze-thaw cycle testing machine. The automatic dry-wet control system is composed of a two-way pump, a flow sensor, an instrument button, a touch screen, a primary water conveying pipe, a secondary water conveying pipe, a water tank and the like, the dry-wet state of concrete is accurately controlled by controlling the power-on direction of the two-way pump and detecting the passing flow of the flow sensor, and meanwhile the dry-wet state of the concrete is changed in the freezing and thawing cycle process. The dynamic coupling of the dry and wet state and the freezing and thawing cycle of the concrete is realized. The device can effectively simulate freeze-thaw damage of concrete in complex dry and wet states in engineering practice, and has high practical value.

Description

Technical Field

[0001] The utility model discloses a concrete dry-wet state and freeze-thaw cycle coupling test device, and relates to the technical field of concrete dry-wet state and freeze-thaw cycle coupling. Background Art

[0002] Concrete freeze-thaw damage is an important problem faced by concrete structures under cold climate conditions. It usually occurs in high latitudes or high altitudes. The key conditions include periodic changes in temperature and the concrete being immersed, saturated or wet. The main cause of the damage is the internal stress caused by the freeze-thaw cycle, including freezing expansion pressure, penetration pressure and crystallization pressure, which causes cracks on the surface of the concrete and gradually erodes from the surface to the inside, affecting the strength and durability in the long term, and may even cause damage to the overall structure.

[0003] In actual engineering, freeze-thaw damage of concrete is usually caused by the coupling of concrete dry-wet state and other factors such as temperature. However, the current test device cannot couple the complex dry-wet state changes of concrete with freeze-thaw cycles, resulting in the test device being unable to obtain test data that is close to reality. Therefore, a test device that couples concrete dry-wet state with freeze-thaw cycles is needed to solve the above problem. Utility Model Content

[0004] The utility model provides a concrete dry-wet state and freeze-thaw cycle coupling test device, which solves the problem that complex dry-wet state and freeze-thaw cycle cannot be coupled in concrete freeze-thaw cycle test, and can better simulate freeze-thaw damage of concrete in actual engineering.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is as follows: a concrete dry-wet state and freeze-thaw cycle coupling test device, including a concrete automatic dry-wet control system, a freeze-thaw cycle box and a freeze-thaw cycle test machine;

[0006] During the test, the concrete specimens are placed in a freeze-thaw cycle box, the dry-wet state of the concrete is adjusted by an automatic dry-wet control system, and the freeze-thaw cycle test is carried out using a freeze-thaw cycle testing machine.

[0007] The automatic concrete dry-wet control system comprises:

[0008] A two-way pump, which is used to pump water in and out of the freeze-thaw cycle box, and serves to connect the freeze-thaw cycle box with the water tank;

[0009] A main water pipe connecting a two-way pump and a water tank;

[0010] A secondary water pipe connecting the freeze-thaw cycle box and the bidirectional pump;

[0011] A water tank, wherein the water tank is filled with water through a water inlet and drained through a drain pipe, and the water level in the water tank can be observed in time through the scale lines on the tank body;

[0012] A card slot, which is used to fix the drainage pipe for subsequent testing;

[0013] A flow sensor, which is embedded in the bidirectional pump and can detect the flow in real time;

[0014] Instrument buttons and touch screen, the touch screen can be set to select different flow and water level change requirements, and confirmed through the instrument buttons;

[0015] The centralized wiring harness includes a bidirectional pump control circuit and a flow sensor transmission circuit. The bidirectional pump control circuit can control the current direction and the power-on duration. The flow sensor transmission circuit can transmit real-time flow data to the touch screen for display.

[0016] Preferably, the bidirectional pump controls the meshing direction of gears inside the pump by changing the direction of the current. During the meshing process of the gears, the water injection and water absorption functions are achieved by the dynamic change of the cavity volume between the gear teeth.

[0017] Preferably, the flow sensor is embedded in the bidirectional pump to record the flow changes in real time, and transmits the flow changes to the touch screen through the transmission line in the centralized wiring harness for real-time display.

[0018] Preferably, at the beginning of the test, the water level change in the freeze-thaw cycle box required for the test can be set on the touch screen, the corresponding flow requirement can be calculated through the touch screen, and then the instrument button is clicked to confirm. Finally, the bidirectional pump will be controlled through the control line in the centralized wiring harness to start the test.

[0019] Preferably, the water level in the box can be understood by observing the scale lines on the box body and the water can be filled or drained in time.

[0020] Preferably, convenient drainage can be achieved through devices such as a drain pipe, a card slot, and a drain pipe cap, making the instrument more convenient and controllable.

[0021] Compared with related technologies, this concrete dry-wet state and freeze-thaw cycle coupling test device has the following beneficial effects:

[0022] 1. Through the automatic dry-wet control system, the bidirectional pump can be controlled to complete the pumping of different water volumes, so that the concrete sample can obtain the dry and wet states under different working conditions. The flow sensor can record the pumped water volume and more accurately calculate and display the change in water level height in the freeze-thaw cycle box.

[0023] 2. By integrating the freeze-thaw cycle machine control system and the automatic wet-dry control system, the wet-dry state of the concrete sample can be changed during the freeze-thaw cycle, and the dynamic coupling of the wet-dry state of the concrete and the freeze-thaw cycle can be achieved, so as to more accurately simulate the freeze-thaw damage of concrete in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of the concrete dry-wet state and freeze-thaw cycle coupling test device provided by the utility model;

[0025] Figure 2 for Figure 1 The enlarged view of the whole after the automatic concrete wet-dry control system and the freeze-thaw cycle box are connected.

[0026] Numbers in the figure: 1. Bidirectional pump, 2. Flow sensor, 3. Main water pipe, 4. Water tank, 5. Water filling port, 6. Card slot, 7. Drain pipe, 8. Scale line on the tank body, 9. Centralized wiring harness, 10. Secondary water pipe, 11. Freeze-thaw cycle box, 12. Instrument button, 13. Touch screen. DETAILED DESCRIPTION

[0027] The implementation of the technical solution is further described in detail below in conjunction with the accompanying drawings. The following implementation scheme is only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

[0028] like Figures 1-2 As shown, a concrete dry-wet state and freeze-thaw cycle coupling test device of the utility model comprises an automatic concrete dry-wet control system, a freeze-thaw cycle box and a freeze-thaw cycle test machine.

[0029] During the test, the concrete specimens are placed in a freeze-thaw cycle box, the dry-wet state of the concrete is adjusted by an automatic dry-wet control system, and the freeze-thaw cycle test is carried out using a freeze-thaw cycle testing machine.

[0030] The concrete automatic dry-wet control system is placed inside the freeze-thaw cycle test machine and includes:

[0031] The two-way pump 1 controls the amount of water in the freeze-thaw cycle box 11 by pumping, and is the hub connecting the water tank 4 and the freeze-thaw cycle box 11.

[0032] The flow sensor 2 is embedded in the bidirectional pump 1 to contact the fluid flowing through the bidirectional pump 1, and can monitor the water volume pumped in and out of the pump in real time; the subsequent touch screen 13 can obtain the water level change in the freeze-thaw cycle box through formula conversion, thereby achieving the purpose of adjusting the dry and wet state of the concrete sample.

[0033] The main water pipe 3 connects the two-way pump 1 and the water tank 4;

[0034] The water tank 4 is filled with water through the water inlet 5 and drained through the drain pipe 7. The water level in the water tank can be observed in time through the scale line 8 on the tank body;

[0035] A card slot 6, used to fix the drain pipe 7 when it is idle;

[0036] Centralized wiring harness 9, which contains bidirectional pump control circuit and flow sensor transmission circuit,

[0037] Wherein, the bidirectional pump control circuit connects the control switch circuit in the bidirectional pump 1 and the instrument button 12;

[0038] The flow sensor transmission line connects the flow sensor 2 and the instrument button 12;

[0039] The instrument button 12 is electrically connected to the touch screen 13 .

[0040] The touch screen 13 realizes the input and output of water by adjusting the current direction of the bidirectional pump.

[0041] The secondary water delivery pipe 10 connects the bidirectional pump 1 and the freeze-thaw cycle box 11 .

[0042] The specific operating steps of the concrete dry-wet state and freeze-thaw cycle coupling test device provided by the utility model are as follows:

[0043] Before conducting a freeze-thaw cycle test on concrete samples, first prepare the concrete according to the test requirements. After the concrete samples are cured and formed, measure the side length data of the concrete test block as a*a*h, and the side length data of the freeze-thaw cycle box as L*L*H. Then put the concrete into the freeze-thaw cycle box, and pour in a certain amount of basic water to determine the basic dry and wet state of the concrete sample.

[0044] Inject a certain amount of water into the water tank through the water tank filling port.

[0045] Place the freeze-thaw cycle box into the freeze-thaw cycle test machine, place the secondary water pipe into the freeze-thaw cycle box along the gap between the sample and the freeze-thaw cycle box 11, pour antifreeze liquid outside the freeze-thaw cycle box, and cover the freeze-thaw cycle test machine.

[0046] Click the instrument button 12 to turn on the instrument (freeze-thaw cycle tester), enter the basic data on the touch screen: the side length a of the specimen, the side length L of the freeze-thaw cycle box, the dry-wet change interval Δh of the concrete specimen, and click the instrument button to confirm uploading the data.

[0047] The backend will use the calculation formula (L 2 -a 2 )Δh=ΔQ is converted into the flow change value ΔQ, ensuring that the bidirectional pump stops working when the corresponding flow value is reached.

[0048] Then, set the test freeze-thaw cycle period and click the instrument button (other button on the freeze-thaw cycle tester) to start the freeze-thaw cycle test.

[0049] When the temperature drops, the control circuit in the centralized wiring harness is energized to enable the bidirectional pump to start pumping water into the freeze-thaw cycle box. At this time, the flow sensor records the flow changes in real time and transmits them to the touch screen through the transmission line in the centralized wiring harness for display. At the same time, the touch screen will also convert the flow change value into the water level change value in the freeze-thaw cycle box through a formula calculation.

[0050] When the water level change value Δh′ reaches the set concrete test block dry-wet change interval Δh, the instrument stops supplying power to the bidirectional pump until the temperature drops to the minimum. Specifically, the touch screen 13 sends a power-off signal to the control switch circuit in the bidirectional pump 1, and the control switch circuit is disconnected.

[0051] When the temperature rises, the control circuit in the centralized wiring harness changes the power supply direction of the two-way pump, causing the two-way pump to start pumping water into the water tank.

[0052] At this time, the flow sensor records the flow changes in real time, and transmits them to the touch screen through the transmission line in the centralized wiring harness and displays them. At the same time, the touch screen will also convert the flow change value into the water level change value in the freeze-thaw cycle box through a formula calculation.

[0053] When the water level change value -Δh′ reaches the set concrete test block dry-wet change interval Δh, the instrument stops supplying power to the bidirectional pump until the temperature rises to the maximum.

[0054] Then repeat the above process.

[0055] After the freeze-thaw cycle test is completed, remove the drain pipe on the card slot, open the drain pipe cap, drain the water, and empty the water in the water tank for subsequent tests.

[0056] The concrete dry-wet state and freeze-thaw cycle coupling test device provided by the utility model adjusts the dry-wet state of the concrete sample by regulating the automatic dry-wet control system of the concrete, and changes the dry-wet state of the concrete sample during the freeze-thaw cycle, thereby realizing the dynamic coupling of the dry-wet state of the concrete and the freeze-thaw cycle. It can effectively simulate the freeze-thaw damage of concrete under complex dry-wet state in actual engineering, and has high practical value.

[0057] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A concrete dry-wet state and freeze-thaw cycle coupling test device, including a concrete automatic dry-wet control system, a freeze-thaw cycle box and a freeze-thaw cycle test machine; The freeze-thaw cycle box is used to place concrete samples, the concrete automatic dry-wet control system is used to adjust the dry-wet state of concrete, and the freeze-thaw cycle test machine is used to conduct freeze-thaw cycle tests; Features: The concrete automatic dry-wet control system is placed in a freeze-thaw cycle test machine and includes: A two-way pump (1), a main water pipe (3) and a secondary water pipe (10), wherein the two-way pump (1) connects the water tank (4) to the freeze-thaw cycle box (11) via the main water pipe (3) and the secondary water pipe (10); A flow sensor (2) is embedded in the bidirectional pump (1) and is used to monitor the amount of water pumped in and out; A centralized wiring harness (9) includes a bidirectional pump control circuit and a flow sensor transmission circuit; wherein the bidirectional pump control circuit connects a control switch circuit in the bidirectional pump (1) and an instrument button (12); and the flow sensor transmission circuit connects the flow sensor (2) and the instrument button (12); The instrument button (12) is electrically connected to the touch screen (13).

2. A concrete dry-wet state and freeze-thaw cycle coupling test device according to claim 1, characterized in that: It also includes a water inlet (5) and a drainage pipe (7), both of which are arranged on the water tank (4).

3. A concrete dry-wet state and freeze-thaw cycle coupling test device according to claim 1, characterized in that: The water tank (4) is provided with tank body scale lines (8).

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