A freeze-thaw-erosion-load coupled concrete damage test device and method

Abstract

The application discloses a freeze-thaw-wind erosion-load coupled concrete damage test device and method, and relates to the technical field of concrete performance test devices.The freeze-thaw-wind erosion-load coupled concrete damage test device comprises a test box, a sand blowing assembly and a temperature control assembly, the test box is provided with a test cavity, a pressure machine for clamping a concrete block and applying a load is arranged on the test box, the sand blowing assembly comprises a sand blowing pipe for conveying wind sand to the concrete block, the angle between the axis of the sand blowing pipe and the axis of the air supply pipe is adjustable, and the temperature control assembly is used for adjusting the temperature in the test cavity.The freeze-thaw-wind erosion-load coupled concrete damage test device can simulate the complex environment of the service of the concrete under the coupling action of freeze-thaw cycles, wind sand erosion and axial load, more accurately reflects the initial damage evolution of the service concrete and the durability degradation law of the concrete with initial damage, and the accuracy of the test research is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete performance testing devices, and in particular to a freeze-thaw-wind erosion-load coupled concrete damage testing device and method. Background Art

[0002] In the northwestern plateau region, characterized by large temperature swings and strong winds, serving concrete structures face the dual damage of freeze-thaw cycles and wind-blown erosion. In an environment characterized by drastic temperature fluctuations between day and night, the water content of the concrete repeatedly freezes and melts, causing volume changes that lead to the formation and expansion of microcracks within the concrete. At the same time, strong winds carry large amounts of sand, which abrasively damages the concrete surface, weakening its erosion resistance and accelerating material degradation. Furthermore, concrete structures are constantly under load during their service, and the application of loads triggers stress concentration, further amplifying the cumulative damage effects of freeze-thaw and wind-blown erosion. The coupled effects of freeze-thaw, wind-blown erosion, and loads overlap and interact with each other, forming a complex coupled damage mechanism that causes concrete deterioration to be much faster than that caused by a single factor, with significant acceleration effects among the multiple factors.

[0003] In related technologies, most test devices can only simulate the effects of a single factor, such as a single freeze-thaw cycle or a single wind-sand erosion. The so-called freeze-thaw cycle and wind-sand erosion coupling test actually applies these two factors in sequence, which is an indirect coupling. It fails to truly achieve the coupling of freeze-thaw cycles and wind-sand erosion, and often ignores the load factors in the service process of concrete. As a result, the test results of existing test devices are difficult to truly and accurately reflect the initial damage evolution of concrete in service in the complex environment of the northwestern plateau and its relationship with durability degradation. Summary of the Invention

[0004] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0005] To this end, an embodiment of the present invention proposes a freeze-thaw-wind erosion-load coupled concrete damage testing device. The freeze-thaw-wind erosion-load coupled concrete damage testing device can simulate the complex service environment of concrete in the northwestern plateau region under the coupled effects of freeze-thaw cycles, wind erosion and axial loads according to test requirements, ensure the authenticity of the test results, more accurately reflect the initial damage evolution of service concrete under the coupling effects of large temperature differences and strong wind and sand, and the durability degradation law of concrete with initial damage, thereby improving the accuracy of experimental research.

[0006] The embodiment of the present invention also provides a freeze-thaw-wind erosion-load coupled concrete damage test method.

[0007] The freeze-thaw-wind erosion-load coupled concrete damage testing device of the embodiment of the present invention comprises:

[0008] A test box having a test cavity, a press for applying a load being provided on the test box, a movable end of the press extending into the test cavity and provided with a first clamping plate at the end thereof, a second clamping plate being provided in the test box corresponding to the first clamping plate, the first clamping plate and the second clamping plate being used to clamp a concrete block;

[0009] A sand blowing assembly includes a blower, an air supply pipe, a sand container, a discharge pipe, and a sand blowing pipe. One end of the air supply pipe is connected to the blower and the other end extends into the test chamber. The sand container is connected to the air supply pipe through the discharge pipe. The sand blowing pipe is movably arranged at the end of the air supply pipe relative to the test chamber. The angle between the axis of the sand blowing pipe and the axis of the air supply pipe is adjustable.

[0010] A temperature control component includes a heating unit and a cooling unit for adjusting the air temperature in the test chamber.

[0011] The freeze-thaw-wind erosion-load coupled concrete damage testing device of the embodiment of the present invention can simulate the complex service environment of concrete in the northwestern plateau region under the coupled effects of freeze-thaw cycles, wind erosion and axial loads according to test requirements, ensure the authenticity of the test results, and more accurately reflect the initial damage evolution of service concrete under the coupling effects of large temperature differences and strong wind and sand, as well as the durability degradation law of concrete with initial damage, thereby improving the accuracy of experimental research.

[0012] In some embodiments, it includes a bracket and a connecting pipe, the bracket is connected to the test box and includes a vertical plate segment and a horizontal plate segment, the vertical plate segment is provided with a ball hinge hole, the connecting pipe can be flexibly deformed or elastically folded, the connecting pipe is connected between the air supply pipe and the sand blowing pipe, the fixed sleeve on the sand blowing pipe is provided with a ball hinge block, and the ball hinge block is hingedly matched with the ball hinge hole.

[0013] In some embodiments, it includes a connecting part, an electric hydraulic push rod and a driving part, the connecting part is provided on the sand blowing pipe, the electric hydraulic push rod is provided on the horizontal plate section, the driving part is provided at the movable end of the electric hydraulic push rod and slides with the connecting part, and the driving part is used to drive the sand blowing pipe to rotate around the ball hinge hole.

[0014] In some embodiments, it includes a fixed plate and a first drive motor, the fixed plate is fixedly provided on the test chamber, a first drive shaft is fixedly provided on the horizontal plate section, the first drive shaft is rotatably provided on the fixed plate, and the first drive motor is transmission-connected to the first drive shaft and is used to drive the bracket to swing around the first drive shaft.

[0015] In some embodiments, a heat exchange box is included, the heat exchange box having a first port and a second port, the air supply pipe includes a first pipe section and a second pipe section, the first pipe section is connected to the first port, and the second pipe section is connected to the second port, the heating unit and the cooling unit are provided in the heat exchange box and are used to adjust the temperature of the air in the heat exchange box;

[0016] And / or, the test box is provided with a temperature and humidity sensor and a humidity adjustment unit, the humidity adjustment unit is used to adjust the humidity of the air in the test chamber, and the temperature and humidity sensor is used to monitor the temperature and humidity in the test chamber.

[0017] In some embodiments, a first clamping plate is rotatably provided on the first clamping plate, and a second clamping plate is rotatably provided on the second clamping plate. The first clamping plate and the second clamping plate are used to clamp the concrete block and drive the concrete block to rotate.

[0018] In some embodiments, a second drive motor is included, a second drive shaft is coaxially and fixedly provided on the second clamping plate, the second drive shaft passes through the second clamping plate, and the second drive motor is fixedly provided on the second clamping plate and is used to drive the second drive shaft to rotate.

[0019] In some embodiments, a receiving hopper is included, the bottom of the test box is connected to a discharge hopper, the discharge hopper is provided with a discharge port, the receiving hopper is provided corresponding to the discharge port and is used to receive the sand discharged from the test box;

[0020] And / or, the test box is provided with a pressure regulating valve, and the pressure regulating valve is used to connect the test cavity with the environment outside the test box to adjust the air pressure in the test cavity.

[0021] In some embodiments, a movable tube is included, which is slidably mounted on the sand blowing tube and is adapted to the size of the sand blowing tube. A fastener is threadedly connected to the movable tube, and the fastener is used to press against the sand blowing tube to fix the position of the movable tube.

[0022] The freeze-thaw-wind erosion-load coupled concrete damage test method of an embodiment of the present invention includes the freeze-thaw-wind erosion-load coupled concrete damage test device of any of the above embodiments, and the test method includes the following steps:

[0023] S1: clamping the concrete block by the first clamping plate and the second clamping plate, and applying a set load to the concrete block by a press;

[0024] S2: The temperature control component is used to increase or decrease the temperature of the air in the test chamber, and the blower is turned on to supply air into the test chamber to verify the temperature in the test chamber so that the air temperature in the test chamber meets the freeze-thaw cycle test requirements under external air supply.

[0025] S3: Start the sand blowing component. The air in the air supply pipe carries the sand discharged from the discharge pipe and impacts the concrete blocks through the sand blowing pipe. The air supply volume of the blower, the discharge speed of the discharge pipe, and the blowing angle of the sand blowing pipe are adjusted to simulate the wind and sand erosion environment in the natural environment.

[0026] S4: After a set period of freeze-thaw cycles and wind erosion, turn off the sand blowing component and temperature control component, increase the load applied by the press on the concrete block until the concrete block is destroyed, and record the set load parameters, environmental condition parameters, and stress change curve of the concrete block during the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the structure of a freeze-thaw-wind erosion-load coupled concrete damage test device according to an embodiment of the present invention.

[0028] Figure 2 It is a structural schematic diagram of a test box in a freeze-thaw-wind erosion-load coupled concrete damage test device according to an embodiment of the present invention.

[0029] Figure 3 Schematic diagram of the connection between the bracket and the fixing plate in the freeze-thaw-wind erosion-load coupled concrete damage test device according to an embodiment of the present invention.

[0030] Figure 4 It is a structural schematic diagram of a sand blowing pipe in a freeze-thaw-wind erosion-load coupled concrete damage testing device according to an embodiment of the present invention.

[0031] Reference numerals:

[0032] Test chamber 1; press 11; first clamping plate 12; first clamping plate 121; second clamping plate 13; second clamping plate 131; concrete block 14; temperature and humidity sensor 15; humidity adjustment unit 16; second drive motor 17; discharge hopper 18; pressure regulating valve 19;

[0033] Sand blowing assembly 2; blower 21; air supply pipe 22; sand container 23; feed pipe 24; sand blowing pipe 25; ball joint block 251; connector 252; slide groove 2521; slide hole 2522; connecting pipe 26; movable pipe 27; fastener 28;

[0034] Temperature control component 3; heating unit 31; cooling unit 32;

[0035] Controller 4;

[0036] Bracket 5; vertical plate section 51; ball hinge hole 511; horizontal plate section 52; electric hydraulic push rod 53; drive member 54; connecting rod 541; slide rod 542;

[0037] Fixed plate 6;

[0038] a first drive motor 7;

[0039] Heat exchange box 8;

[0040] Receiving hopper 9. DETAILED DESCRIPTION

[0041] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0042] like Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the freeze-thaw-wind erosion-load coupled concrete damage test device of the embodiment of the present invention includes a test box 1, a sand blowing component 2 and a temperature control component 3. The test box 1 has a test cavity. A press 11 for applying a load is provided on the test box 1. The movable end of the press 11 extends into the test cavity and is provided with a first clamping plate 12 at the end. A second clamping plate 13 is provided in the test box 1 corresponding to the first clamping plate 12. The first clamping plate 12 and the second clamping plate 13 are used to clamp a concrete block 14. The sand blowing component 2 includes an air supply. The test chamber comprises a machine 21, an air supply pipe 22, a sand container 23, a discharge pipe 24 and a sand blowing pipe 25. One end of the air supply pipe 22 is connected to the air supply machine 21 and the other end extends into the test chamber. The sand container 23 is connected to the air supply pipe 22 through the discharge pipe 24. The sand blowing pipe 25 is movably arranged at the end of the air supply pipe 22 relative to the test chamber 1. The angle between the axis of the sand blowing pipe 25 and the axis of the air supply pipe 22 is adjustable. The temperature control component 3 includes a heating unit 31 and a cooling unit 32 for adjusting the air temperature in the test chamber.

[0043] When the freeze-thaw-wind erosion-load coupled concrete damage test device of the embodiment of the present invention is in use, the movable end of the press 11 can be moved to drive the first clamping plate 12 to move, and the first clamping plate 12 and the second clamping plate 13 can be used to clamp and fix the concrete block 14 in the test chamber, and pressure can be applied to the concrete block 14 by the press 11 to simulate the stress condition of the concrete block 14 in a natural environment. The temperature in the test chamber can be adjusted by the temperature control component 3 to achieve a cyclic change of the air temperature in the test chamber to increase and decrease, thereby simulating the freeze-thaw cycle of the concrete block 14 in a natural environment, and the wind and sand transported by the sand blowing pipe 25 can achieve wind and sand erosion of the concrete block 14, and the sand blowing angle of the sand blowing pipe 25 can be adjusted to achieve a more realistic simulation of wind and sand erosion, and at the same time, the freeze-thaw cycle, wind and sand erosion and axial load can be synchronously applied to the complex environment in which the concrete block 14 serves, thereby ensuring the authenticity of the test results.

[0044] The freeze-thaw-wind erosion-load coupled concrete damage testing device of the embodiment of the present invention can simulate the complex service environment of concrete in the northwestern plateau region under the coupled effects of freeze-thaw cycles, wind erosion and axial loads according to test requirements, ensure the authenticity of the test results, and more accurately reflect the initial damage evolution of service concrete under the coupling effects of large temperature differences and strong wind and sand, as well as the durability degradation law of concrete with initial damage, thereby improving the accuracy of experimental research.

[0045] Optionally, a controller 4 is included, which is provided with a display screen and control buttons. The controller 4 is electrically connected to the press 11, the air blower 21, the heating unit 31 and the refrigeration unit 32 to control the start and stop operations of the press 11, the air blower 21, the heating unit 31 and the refrigeration unit 32.

[0046] Optionally, the heating unit 31 is a heater, the cooling unit 32 is a refrigerator, and the blower 21 is an air compressor.

[0047] Optionally, a valve is provided on the discharge pipe 24 , and the valve is used to control the opening and closing of the discharge pipe 24 and to adjust the falling flow rate of sand in the discharge pipe 24 .

[0048] Optionally, the test box 1 is provided with a box door, and the box door is provided with a glass window to facilitate observation of the test process in the test chamber.

[0049] In some embodiments, as Figure 2 and Figure 3 As shown, it includes a bracket 5 and a connecting pipe 26. The bracket 5 is connected to the test box 1 and includes a vertical plate section 51 and a horizontal plate section 52. The vertical plate section 51 is provided with a ball hinge hole 511. The connecting pipe 26 can be flexibly deformed or elastically folded. The connecting pipe 26 is connected between the air supply pipe 22 and the sand blowing pipe 25. The sand blowing pipe 25 is fixedly sleeved with a ball hinge block 251. The ball hinge block 251 is hinged to the ball hinge hole 511. The blowing pipe is assembled on the vertical plate section 51 through the hinge block. The blowing pipe can be rotated around the ball center of the ball hinge hole 511 to adjust the air outlet angle of the blowing pipe, thereby realizing wind and sand erosion under different parameters of the concrete block 14, ensuring the accuracy of the simulation of the wind and sand erosion environment, and is easy to operate and adjust.

[0050] Optionally, the connecting pipe 26 is a rubber hose.

[0051] Optionally, the connecting pipe 26 is a bellows and can be made of metal or rubber.

[0052] In some embodiments, as Figure 2 and Figure 3As shown, it includes a connecting member 252, an electric hydraulic push rod 53 and a driving member 54. The connecting member 252 is provided on the sand blowing pipe 25, the electric hydraulic push rod 53 is provided on the horizontal plate section 52, and the driving member 54 is provided at the movable end of the electric hydraulic push rod 53 and slidingly cooperates with the connecting member 252. The driving member 54 is used to drive the sand blowing pipe 25 to rotate around the ball hinge hole 511.

[0053] Specifically, the cross section of the connecting member 252 is U-shaped and includes a limit plate and connecting plates arranged on both sides of the limit plate. The connecting plate is fixedly connected to the sand blowing pipe 25. A slide groove 2521 is limited between the connecting member 252 and the sand blowing pipe 25. A slide hole 2522 extending along the axial direction of the sand blowing pipe 25 is provided on the limit plate. The driving member 54 is T-shaped and includes a connecting rod 541 and a slide rod 542. One end of the connecting rod 541 is fixedly connected to one end of the electric hydraulic push rod 53. The slide rod 542 is vertically and fixedly arranged at the other end of the connecting rod 541. The connecting rod 541 passes through the slide hole 2522 and extends into the slide groove 25 21, the slide rod 542 slides and fits in the slide groove 2521, and the diameter of the slide rod 542 is adapted to the size of the slide groove 2521. When the electric hydraulic push rod 53 is extended, the slide rod 542 moves in the slide groove 2521 in a direction away from the ball hinge hole 511 to drive the outlet of the sand blowing pipe 25 to move in a direction away from the horizontal plate section 52. When the electric hydraulic push rod 53 is shortened, the slide rod 542 moves in the slide groove 2521 in a direction close to the ball hinge hole 511 to drive the outlet of the sand blowing pipe 25 to move in a direction close to the horizontal plate section 52, thereby realizing the control and adjustment of the swing of the sand blowing pipe 25.

[0054] Optionally, the bracket 5 is T-shaped or L-shaped, and one end of the horizontal plate section 52 is fixedly connected to the inner wall of the test box 1 .

[0055] Optionally, the electric hydraulic push rod 53 is electrically connected to the control machine, and the operation of the electric hydraulic push rod 53 can be controlled by the controller 4 .

[0056] In some embodiments, as Figure 2 and Figure 3 As shown, it includes a fixed plate 6 and a first drive motor 7. The fixed plate 6 is fixed to the test chamber. A first drive shaft is fixed on the horizontal plate section 52. The first drive shaft is rotatably arranged on the fixed plate 6. The first drive motor 7 is connected to the first drive shaft and is used to drive the bracket 5 to swing around the first drive shaft.

[0057] Specifically, the bracket 5 is L-shaped, the first drive motor 7 is fixedly arranged on the fixed plate 6, the first gear is provided on the output shaft of the first drive motor 7, the first drive shaft on the horizontal plate section 52 passes through the fixed plate 6, and the first drive shaft is provided with a second gear. The first gear and the second gear are engaged for transmission. When the first drive motor 7 rotates, the first gear drives the second gear to rotate, and then drives the bracket 5 to rotate around the first drive shaft, thereby realizing the adjustment of the sand blowing angle of the sand blowing pipe 25 in the horizontal direction. The operation is convenient, and the simulation of the change of the blowing angle in the wind and sand erosion environment is ensured, so as to ensure the accuracy of the measurement data.

[0058] Optionally, the first drive shaft extends along the extension direction of the vertical plate segment 51 , and the axis of the first drive shaft passes through the center of the spherical hinge hole 511 .

[0059] Optionally, the first drive motor 7 is a stepping motor and is electrically connected to the controller 4 , and the controller 4 can control the rotation angle and rotation direction of the first drive motor 7 .

[0060] In some embodiments, as Figure 1 As shown, the heat exchange box 8 includes a first port and a second port, the air supply pipe 22 includes a first pipe section and a second pipe section, the first pipe section is connected to the first port, and the second pipe section is connected to the second port, and the heating unit 31 and the cooling unit 32 are provided in the heat exchange box 8 and are used to adjust the temperature of the air in the heat exchange box 8;

[0061] Specifically, the heat exchange box 8 has a heat exchange cavity, and a first port and a second port strongly connected to the heat exchange are respectively provided on opposite sides of the heat exchange box 8. A heating unit 31 and a cooling unit 32 are respectively provided on the side walls of the heat exchange box 8. The air outlets of the heating unit 31 and the cooling unit 32 are respectively connected to the heat exchange cavity. The two ends of the first pipe section are respectively connected to the air supply fan 21 and the first port, and the two ends of the second pipe section are respectively connected to the second port and the sand blowing pipe 25. By preheating or precooling the air in the heat exchange cavity, the temperature of the wind and sand blown out through the sand blowing pipe 25 is ensured to be the same as the air temperature in the test cavity, avoiding a large temperature difference that affects the air temperature in the test cavity. At the same time, it avoids the wind and sand erosion point on the concrete block 14 being suddenly subjected to a large temperature difference at the set temperature, which increases the uncertainty factor in the test of the concrete block 14. The authenticity of the experimental results can be ensured, and the initial damage evolution of the serving concrete under the coupling of large temperature difference and strong wind and sand and the durability degradation law of the concrete with initial damage are more accurately reflected, thereby improving the accuracy of the experimental research.

[0062] In some embodiments, as Figure 2As shown, the test chamber 1 is provided with a temperature and humidity sensor 15 and a humidity adjustment unit 16. The humidity adjustment unit 16 is used to adjust the humidity of the air in the test chamber, and the temperature and humidity sensor 15 is used to monitor the temperature and humidity in the test chamber. By providing the humidity adjustment unit 16, the erosion of the concrete block 14 in the natural environment can be further simulated, and the temperature and humidity of the air in the test chamber can be accurately controlled by the temperature and humidity sensor 15, which is convenient to operate.

[0063] Optionally, the humidity adjustment unit 16 is a humidifier, and the humidifier and the temperature and humidity sensor 15 are both electrically connected to the controller 4 .

[0064] In some embodiments, as Figure 2 As shown, a first clamping plate 121 is rotatably provided on the first clamping plate 12, and a second clamping plate 131 is rotatably provided on the second clamping plate 13. The first clamping plate 121 and the second clamping plate 131 are used to clamp the concrete block 14 and to drive the concrete block 14 to rotate. By providing the first clamping plate 121 and the second clamping plate 131, when the first clamping plate 12 and the second clamping plate 13 clamp the concrete block 14, the rotation of the concrete block 14 can be adjusted by rotating the first clamping plate 121 and the second clamping plate 131, thereby adjusting the wind and sand erosion position of the concrete block 14, and the operation is convenient.

[0065] Optionally, the first clamping plate 12 and the first clamping plate 121 are connected via a rotating bearing, and the second clamping plates 131 and the second clamping plates 131 are also connected via a rotating bearing.

[0066] In some embodiments, as Figure 2 As shown, it includes a second drive motor 17, a second drive shaft is coaxially and fixedly provided on the second clamping plate 131, the second drive shaft passes through the second clamping plate 13, and the second drive motor 17 is fixedly provided on the second clamping plate 13 and is used to drive the second drive shaft to rotate.

[0067] Specifically, the second clamping plate 13 is fixed to the test chamber by a diagonal brace, the second drive motor 17 is fixedly arranged on the side of the second clamping plate 13 facing away from the first clamping plate 12, the second drive shaft on the second clamping plate 131 passes through the second clamping plate 13, and the output shaft of the second drive motor 17 is connected to the second drive shaft through a coupling. The second drive motor 17 can directly drive the second clamping plate 131 to rotate, thereby realizing the rotation adjustment of the concrete block 14.

[0068] Optionally, the second drive motor 17 is electrically connected to the controller 4 .

[0069] In some embodiments, as Figure 2 As shown, it includes a receiving hopper 9, and a discharge hopper 18 is connected to the bottom of the test box 1. The discharge hopper 18 is provided with a discharge port. The receiving hopper 9 is set corresponding to the discharge port and is used to receive the sand discharged from the test box 1.

[0070] Specifically, the discharge port of the discharge hopper 18 is set at the end with a smaller diameter of the discharge hopper 18, and a discharge pipe is provided on the discharge port, a control valve is provided on the discharge pipe, and a receiving box is provided at the end of the discharge pipe. A receiving hopper 9 is movably provided in the receiving box. The height of the receiving hopper 9 is the same as the height of the receiving box, and the top of the receiving hopper 9 is provided with an annular sealing strip extending along the circumferential direction. A plurality of handles are provided at intervals on the circumferential side of the receiving hopper 9, and an observation window is provided on the receiving hopper 9. By opening the control valve, the sand in the discharge hopper 18 enters the receiving hopper 9 through the discharge pipe. The height of the sand in the receiving hopper 9 can be observed through the observation window, so as to close the control valve in time, and seal the gap between the receiving hopper 9 and the top wall of the receiving box through the sealing strip to ensure that the sand does not fly during the discharge process, which is environmentally friendly and tidy.

[0071] Alternatively, the discharge port is provided on the inclined side wall of the discharge hopper 18, and a discharge plate is provided corresponding to the discharge port. A receiving trough is provided at an angle corresponding to the discharge port below the discharge hopper 18, and a receiving hopper 9 is provided corresponding to the discharge end of the receiving trough. By opening the discharge plate, the sand enters the receiving trough through the discharge port and is finally collected in the receiving hopper 9.

[0072] In some embodiments, as Figure 1 and Figure 2 As shown, the test chamber 1 is provided with a pressure regulating valve 19, which is used to connect the test chamber with the environment outside the test chamber 1 to adjust the air pressure in the test chamber. By providing the pressure regulating valve 19, when the gas pressure in the test chamber is relatively high, the pressure regulating valve 19 can be automatically opened to discharge part of the gas, thereby ensuring that the air pressure in the test chamber is the same as the ambient pressure under natural regulation, thereby ensuring accurate simulation of the service environment of the concrete block 14.

[0073] In some embodiments, as Figure 4 As shown, it includes a movable tube 27, which is slidably mounted on the sand blowing tube 25 and is adapted to the size of the sand blowing tube 25. A fastener 28 is threadedly connected to the movable tube 27, and the fastener 28 is used to press against the sand blowing tube 25 to fix the position of the movable tube 27. By moving the position of the movable tube 27 on the sand blowing tube 25, the usable length of the sand blowing tube 25 can be increased, which is convenient for controlling the position where the wind and sand enter the test chamber and is easy to operate.

[0074] Optionally, the fastener 28 is a fastening bolt.

[0075] The following describes a freeze-thaw-wind erosion-load coupled concrete damage test method according to an embodiment of the present invention.

[0076] The freeze-thaw-wind erosion-load coupled concrete damage test method of an embodiment of the present invention includes the freeze-thaw-wind erosion-load coupled concrete damage test device of any of the above embodiments, and the test method includes the following steps:

[0077] S1: clamping the concrete block by the first clamping plate and the second clamping plate, and applying a set load to the concrete block by a press;

[0078] S2: The temperature control component is used to raise and lower the air temperature in the test chamber to create an ice-melting environment for the concrete blocks. The blower is turned on to supply air into the test chamber to verify whether the temperature in the test chamber meets the experimental requirements. The set temperatures of the cooling unit and heating unit are adjusted to ensure that the air temperature in the test chamber meets the requirements of the freeze-thaw cycle experiment under external air supply.

[0079] S3: Start the sand blowing component. The air in the air supply pipe carries the sand discharged from the discharge pipe and impacts the concrete blocks through the sand blowing pipe. The air supply volume of the blower, the discharge speed of the discharge pipe, and the blowing angle of the sand blowing pipe are adjusted to simulate the wind and sand erosion environment in the natural environment.

[0080] S4: After a set period of freeze-thaw cycles and wind erosion, turn off the sand blowing component and temperature control component, increase the load applied by the press on the concrete block until the concrete block is destroyed, and record the set load parameters, environmental condition parameters, and stress change curve of the concrete block during the test.

[0081] The freeze-thaw-wind erosion-load coupled concrete damage test method of the embodiment of the present invention can simulate the complex service environment of concrete in the northwestern plateau region under the coupled effects of freeze-thaw cycles, wind erosion, and axial loads, ensure the authenticity of the test results, and more accurately reflect the initial damage evolution of service concrete under the coupling effects of large temperature differences and strong wind and sand, as well as the durability degradation law of concrete with initial damage, thereby improving the accuracy of experimental research.

[0082] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0083] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0084] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0085] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0086] In the description of this specification, the reference terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0087] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A freeze-thaw-wind erosion-load coupled concrete damage test device, characterized in that: include: A test box having a test cavity, a press for applying a load being provided on the test box, a movable end of the press extending into the test cavity and provided with a first clamping plate at the end thereof, a second clamping plate being provided in the test box corresponding to the first clamping plate, the first clamping plate and the second clamping plate being used to clamp a concrete block; A sand blowing assembly includes a blower, an air supply pipe, a sand container, a discharge pipe, and a sand blowing pipe. One end of the air supply pipe is connected to the blower and the other end extends into the test chamber. The sand container is connected to the air supply pipe through the discharge pipe. The sand blowing pipe is movably arranged at the end of the air supply pipe relative to the test chamber. The angle between the axis of the sand blowing pipe and the axis of the air supply pipe is adjustable. a temperature control assembly, the temperature control assembly comprising a heating unit and a cooling unit for regulating the temperature of the air in the test chamber; A bracket and a connecting pipe, wherein the bracket is connected to the test box and includes a vertical plate segment and a horizontal plate segment, the vertical plate segment is provided with a ball hinge hole, the connecting pipe is flexibly deformable or elastically foldable, the connecting pipe is connected between the air supply pipe and the sand blowing pipe, and a fixed sleeve on the sand blowing pipe is provided with a ball hinge block, and the ball hinge block is hingedly matched with the ball hinge hole; A connecting member, an electric hydraulic push rod and a driving member, wherein the connecting member is provided on the sand blowing pipe, the electric hydraulic push rod is provided on the horizontal plate section, the driving member is provided at the movable end of the electric hydraulic push rod and is slidably matched with the connecting member, and the driving member is used to drive the sand blowing pipe to rotate around the ball hinge hole; A heat exchange box having a first port and a second port, the air supply pipe comprising a first pipe section and a second pipe section, the first pipe section being connected to the first port, the second pipe section being connected to the second port, the heating unit and the cooling unit being provided in the heat exchange box and being used to adjust the temperature of the air in the heat exchange box; The test box is provided with a temperature and humidity sensor and a humidity adjustment unit. The humidity adjustment unit is used to adjust the humidity of the air in the test chamber, and the temperature and humidity sensor is used to monitor the temperature and humidity in the test chamber.

2. The freeze-thaw-wind erosion-load coupled concrete damage testing device according to claim 1 is characterized in that: It includes a fixed plate and a first drive motor, the fixed plate is fixedly arranged on the test cavity, the first drive shaft is fixedly arranged on the horizontal plate section, the first drive shaft is rotatably arranged on the fixed plate, and the first drive motor is transmission-connected to the first drive shaft and is used to drive the bracket to swing around the first drive shaft.

3. The freeze-thaw-wind erosion-load coupled concrete damage testing device according to claim 1, characterized in that: A first clamping plate is rotatably provided on the first clamping plate, and a second clamping plate is rotatably provided on the second clamping plate. The first clamping plate and the second clamping plate are used to clamp the concrete block and drive the concrete block to rotate.

4. The freeze-thaw-wind erosion-load coupled concrete damage testing device according to claim 3, characterized in that: It includes a second drive motor, a second drive shaft is coaxially and fixedly provided on the second clamping plate, the second drive shaft passes through the second clamping plate, and the second drive motor is fixedly provided on the second clamping plate and is used to drive the second drive shaft to rotate.

5. The freeze-thaw-wind erosion-load coupled concrete damage testing device according to claim 1, characterized in that: The test box comprises a receiving hopper, the bottom of which is connected to a discharge hopper, the discharge hopper is provided with a discharge port, the receiving hopper is arranged corresponding to the discharge port and is used to receive the sand discharged from the test box; And / or, the test box is provided with a pressure regulating valve, and the pressure regulating valve is used to connect the test cavity with the environment outside the test box to adjust the air pressure in the test cavity.

6. The freeze-thaw-wind erosion-load coupled concrete damage testing device according to claim 1, characterized in that: The movable tube comprises a movable tube which is slidably sleeved on the sand blowing tube and matched with the sand blowing tube in size. A fastener is threadedly connected on the movable tube and is used to press against the sand blowing tube to fix the position of the movable tube.

7. A freeze-thaw-wind erosion-load coupled concrete damage test method, characterized in that: Based on the freeze-thaw-wind erosion-load coupled concrete damage testing device according to any one of claims 1 to 6, the testing method comprises the following steps: S1: clamping the concrete block by the first clamping plate and the second clamping plate, and applying a set load to the concrete block by a press; S2: The temperature control component is used to increase or decrease the temperature of the air in the test chamber, and the blower is turned on to supply air into the test chamber to verify the temperature in the test chamber so that the air temperature in the test chamber meets the freeze-thaw cycle test requirements under external air supply. S3: Start the sand blowing component. The air in the air supply pipe carries the sand discharged from the discharge pipe and impacts the concrete blocks through the sand blowing pipe. The air supply volume of the blower, the discharge speed of the discharge pipe, and the blowing angle of the sand blowing pipe are adjusted to simulate the wind and sand erosion environment in the natural environment. S4: After a set period of freeze-thaw cycles and wind erosion, turn off the sand blowing component and temperature control component, increase the load applied by the press on the concrete block until the concrete block is destroyed, and record the set load parameters, environmental condition parameters, and stress change curve of the concrete block during the test.

Images