Device and method for testing surface cracks in expansive soil under temperature and humidity controllable boundaries

Abstract

The present invention relates to the technical field of expansive soil testing experiments, and discloses an expansive soil surface crack testing device under a temperature and humidity controllable boundary, comprising a constant temperature and humidity chamber, a soil sample placement mechanism arranged in the constant temperature and humidity chamber, and a processing mechanism for spraying and drying the soil sample. The constant temperature and humidity chamber consists of a base and a top cover detachably mounted above the base. The soil sample placement mechanism is provided with a plurality of groups distributed in a circumferential array along the same axis, and the soil sample placement mechanism comprises a circular placement table and a rotating drum coaxially arranged outside the placement table, and the placement table is used to place the soil sample. The processing mechanism comprises a power component and a plurality of groups of execution components, and the plurality of execution components are respectively mounted on each rotating drum. The present invention can conveniently and automatically carry out all-round and uniform humidification and drying of the soil sample, and can obtain image information of each position of the soil sample in real time, test multiple soil samples at one time, and improve work efficiency and the accuracy of the test results.

Description

Technical Field

[0001] The invention relates to the technical field of expansive soil testing experiments, and in particular to an expansive soil surface crack testing device and a testing method under a temperature and humidity controllable boundary. Background Art

[0002] Expansive soil is a special type of unsaturated soil with pronounced shrinkage and swelling properties. Cracks develop during its shrinkage due to water loss. The presence of these cracks provides pathways for rainwater to enter the soil, increasing the soil's permeability. Field tests have shown that when cracks develop in expansive soil, its in-situ permeability can reach levels similar to those of sandy soils, making it highly permeable. This increase in permeability leads to saturation of the soil, reducing its strength. For expansive soil slopes, this reduces safety and makes them more susceptible to landslides and other engineering accidents. The development of cracks in expansive soil is correlated with its water content. Only when cracks develop to a certain extent do they affect permeability. The water content at this point is called the cracking water content. This cracking water content is crucial for studying the permeability and strength of expansive soil.

[0003] At present, the research on expansive soil mainly focuses on its crack characteristics, but there are the following problems: naked eye observation is used, which is easily affected by subjective factors and lacks persuasiveness. Summary of the Invention

[0004] In order to solve the technical problems raised in the background technology, the present invention provides an expansive soil surface crack testing device under a temperature and humidity controllable boundary.

[0005] The present invention is implemented by the following technical solution: a surface crack testing device for expansive soil under temperature and humidity controllable boundaries, comprising a constant temperature and humidity chamber, a soil sample placement mechanism arranged in the constant temperature and humidity chamber, and a processing mechanism for spraying and drying the soil sample.

[0006] The constant temperature and humidity chamber consists of a base and a top cover that is detachably mounted above the base.

[0007] The soil sample placing mechanism is provided with several groups of circumferential arrays along the same axis. The soil sample placing mechanism comprises a circular placing table and a rotary drum coaxially arranged outside the placing table. The placing table is used to place soil samples.

[0008] The processing mechanism includes a power component and several groups of execution components. The several execution components are respectively installed on each rotary drum. The power component is used to drive the rotary drum to rotate.

[0009] As a further improvement of the above scheme, the outer ring of each rotating drum is provided with a driven gear ring, the power assembly includes a rotating ring rotatably mounted on the base, the outer ring of the rotating ring is provided with an active outer gear ring, the inner ring of the rotating ring is provided with an active inner gear ring, the active inner gear ring is engaged with each driven gear ring, and the drive assembly also includes a drive motor mounted on the base and a drive gear connected to the output shaft of the drive motor, the drive gear is engaged with the active outer gear ring.

[0010] Through the above structure, while testing multiple soil samples, each rotary drum and the actuator on the rotary drum can be driven to rotate, the soil samples can be humidified and dried uniformly in all directions, and no blind angle shooting can be achieved.

[0011] As a further improvement of the above scheme, the execution component includes a support rod fixed on the top surface of the rotary drum, a spray unit and a drying unit installed on the support rod, and several grooves are distributed on the side of the support rod close to the soil sample. A high-definition camera for obtaining soil sample image information is installed in each groove; the image obtained by the high-definition camera is transmitted to a memory card for storage, and can be connected to an external display screen via a cable, so as to facilitate real-time display and monitoring.

[0012] As a further improvement to the above solution, the spray unit includes a water tank fixed to the outside of the support rod. A delivery channel is provided within the support rod. Each groove is circumferentially arrayed with a plurality of first and second spray holes, each connected to the delivery channel. Atomizing nozzles can be installed at the outlets of both first and second spray holes to evenly humidify the soil sample and prevent excessive water pressure from damaging the soil surface.

[0013] As a further improvement to the above solution, mounting slots are provided on opposite sides of the groove. Cover plates are slidably installed in each mounting slot, capable of closing the corresponding slot opening. Electromagnets are installed in the mounting slots, providing magnetic attraction for the cover plates. The inner ends of the cover plates are connected to the inner wall of the mounting slot via an elastic return mechanism. When spraying water, the cover plates can be closed to prevent water droplets from remaining on the camera surface and affecting image quality.

[0014] As a further improvement to the above solution, a slot is provided on one side of the first water spray hole, a positioning rod is movably installed in the slot, and a connecting chamber is provided between the slot and the first water spray hole. A drive wheel is rotatably installed in the connecting chamber. One side of the drive wheel is located in the first water spray hole and can be driven by water flow. The other side of the drive wheel is provided with a gear ring that meshes with a toothed plate installed on the outside of the positioning rod. One end of the positioning rod can be inserted into the installation slot, and a positioning slot is provided on the side of the cover plate that can cooperate with the end of the positioning rod. Through the above structure, it is possible to achieve that during the water spraying process, the positioning rod and the positioning slot are separated by the water flow, thereby causing the cover plate to automatically close.

[0015] As a further improvement of the above scheme, the drying unit includes a hot air blower installed on the support rod, an air duct opened in the support rod, and blowing hole 1 and blowing hole 2 distributed on the side of the support rod adjacent to the soil sample, blowing hole 1 and blowing hole 2 are connected to the air duct, and the air inlet of the air duct is connected to the air outlet of the hot air blower.

[0016] As a further improvement of the above solution, an air cavity is opened adjacent to the groove, one side of the air cavity is connected to the air duct through a connecting hole, and the other side of the air cavity is connected to the inside of the installation groove through a plurality of air outlet holes.

[0017] As a further improvement of the above solution, the top cover is made of a transparent material, and is magnetically attracted and sealed to the top surface of the base.

[0018] This proposal also proposes a method for using the expansive soil surface crack testing device under a temperature and humidity controllable boundary, including the following steps:

[0019] Step 1: Open the top cover and place the soil sample in the soil sample placement mechanism on the base;

[0020] Step 2: After the soil sample is placed, the top cover and base are installed to maintain a constant temperature and humidity inside the space;

[0021] Step 3: Open the processing mechanism to work, repeatedly spray and dry the soil sample, and use a high-definition camera to obtain crack information on the outer surface of the soil sample during this process.

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

[0023] The testing device proposed in the present invention includes a constant temperature and humidity chamber, a soil sample placement mechanism located within the chamber, and a processing mechanism for spraying and drying the soil samples. The constant temperature and humidity chamber consists of a base and a removable top cover mounted above the base. The soil sample placement mechanism is arranged in a circumferential array along a common axis. The soil sample placement mechanism includes a circular placement table and a rotating drum coaxially arranged outside the placement table. The placement table is used to place the soil sample. The processing mechanism includes a power assembly and several groups of actuators, each of which is mounted on a respective rotating drum. The power assembly is used to drive the rotating drum to rotate.

[0024] The present invention can conveniently and automatically humidify and dry soil samples uniformly in all directions, and can obtain image information of various positions of the soil samples in real time, test multiple soil samples at one time, and improve work efficiency and the accuracy of test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2It is a top view schematic diagram of the structure on the base of the present invention;

[0027] Figure 3 For the present invention Figure 1 Enlarged view of point A in the middle;

[0028] Figure 4 For the present invention Figure 3 Enlarged view of point B in the middle;

[0029] Figure 5 It is a structural schematic diagram of the air cavity, the communicating hole and the air duct of the present invention;

[0030] Figure 6 It is a side structural schematic diagram of the support rod of the present invention;

[0031] Description of main symbols:

[0032] In the figure: base 1, soil sample 2, support rod 3, top cover 4, drive motor 5, rotating ring 6, drive gear 7, water tank 8, temperature and humidity sensor 9, rotating drum 10, high-definition camera 11, conveying channel 12, water spray hole 13, mounting slot 14, electromagnet 15, elastic recovery mechanism 16, cover 17, positioning rod 18, positioning slot 19, drive wheel 20, slot 21, blowing hole 1 22, blowing hole 2 23, spray hole 2 24, air outlet 26, air cavity 27, connecting hole 28, air duct 29. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0034] Example 1

[0035] Please combine Figure 1-6 The device for testing surface cracks in expansive soil under controlled temperature and humidity conditions includes a constant temperature and humidity chamber, a soil sample placement mechanism within the chamber, and a processing mechanism for spraying and drying the soil samples. The chamber consists of a base 1 and a removable cover 4 mounted above the base 1. The soil sample placement mechanism comprises several groups of circumferentially arranged arrays along a common axis. The soil sample placement mechanism comprises a circular placement table and a rotating drum 10 coaxially disposed outside the placement table. The placement table is used to place the soil sample 2.

[0036] The processing mechanism includes a power assembly and several groups of execution assemblies. The several execution assemblies are respectively installed on each rotary drum 10. The power assembly is used to drive the rotary drum 10 to rotate.

[0037] In this embodiment, a driven gear ring is provided on the outer ring of each rotating drum 10, and the power assembly includes a rotating ring 6 rotatably mounted on the base 1, the outer ring of the rotating ring 6 is mounted with an active outer gear ring (not marked), the inner ring of the rotating ring 6 is provided with an active inner gear ring (not marked), the active inner gear ring is meshed with each driven gear ring, and the driving assembly also includes a driving motor 5 mounted on the base 1 and a driving gear 7 connected to the output shaft of the driving motor 5, and the driving gear 7 is meshed with the active outer gear ring.

[0038] Through the above structure, while testing multiple soil samples, each rotary drum 10 and the actuator on the rotary drum 10 can be driven to rotate, the soil samples can be humidified and dried uniformly in all directions, and 360-degree shooting without blind spots can be achieved.

[0039] It should be noted that, in this solution, the execution assembly includes a support rod 3 fixed to the top surface of the rotary drum 10, a spray unit and a drying unit installed on the support rod 3, and a plurality of grooves are distributed on the side of the support rod 3 close to the soil sample, and a high-definition camera 11 for obtaining soil sample image information is installed in each groove; the image obtained by the high-definition camera is transmitted to the memory card for storage, and can be connected to an external display screen via a cable, so as to facilitate real-time display and monitoring.

[0040] It is worth noting that the spray unit includes a water tank 8 fixed to the outside of the support rod 3. A delivery channel 12 is provided within the support rod 3. Each groove is circumferentially arrayed with a plurality of water spray holes 13 and spray holes 24 that communicate with the delivery channel 12. Atomizing nozzles can be installed at the outlets of the water spray holes 13 and spray holes 24 to evenly humidify the soil sample and prevent excessive water pressure from damaging the soil sample surface.

[0041] As an optional embodiment of the present invention, mounting slots 14 are provided on opposite sides of the groove. Cover plates 17 are slidably mounted within each mounting slot 14, capable of closing the corresponding slot opening. An electromagnet 15 is positioned within the mounting slot 15, and the cover plates 17 are magnetically attracted. The inner ends of the cover plates 17 are connected to the inner wall of the mounting slot via an elastic return mechanism 16. When spraying water, the cover plates 17 can be closed to prevent water droplets from remaining on the camera surface and affecting image quality.

[0042] In order to make the use more intelligent, please refer to Figure 5A slot 21 is provided on one side of the water spray hole 13. A positioning rod 18 is movably mounted within slot 21. A connecting chamber is provided between slot 21 and the water spray hole 13. A drive wheel is rotatably mounted within the connecting chamber. One side of the drive wheel is located in the water spray hole 13 and can be driven by the water flow. The other side of the drive wheel is provided with a gear ring that meshes with a toothed plate mounted on the outside of positioning rod 18. One end of positioning rod 18 can be inserted into mounting slot 14. A positioning slot 19 is provided on the side of cover plate 17 that can mate with the end of positioning rod 18. Through this structure, during the water spraying process, the positioning rod and positioning slot 19 are separated by the water flow, causing the cover plate to automatically close.

[0043] Optionally, the drying unit includes a hot air blower installed on the support rod 3, an air duct 29 opened in the support rod 3, and a blowing hole 1 22 and a blowing hole 2 23 distributed on one side of the soil sample 2 adjacent to the support rod 3. The blowing hole 1 22, the blowing hole 2 23 and the air duct 29 are connected, and the air inlet of the air duct 29 is connected to the air outlet of the hot air blower.

[0044] In this embodiment, an air cavity 27 is provided adjacent to the groove. One side of the air cavity 27 is connected to the air duct 29 via a connecting hole 28 , and the other side of the air cavity 27 is connected to the interior of the mounting groove 14 via a plurality of air outlet holes 26 .

[0045] For easy observation, the top cover 4 in this solution is made of transparent material, and is magnetically attracted and sealed to the top surface of the base 1, which can effectively seal its internal space to form a stable constant temperature and humidity environment. A temperature and humidity sensor 9 is provided in the top cover 4, which can monitor the temperature and humidity conditions of the internal space in real time.

[0046] Example 2

[0047] To prevent excessive humidity within the space, this solution incorporates a humidity control mechanism. This mechanism includes an evaporator mounted inside the top cover, connected to a compressor outside the top cover. The compressor is controlled by a temperature and humidity sensor. The evaporator condenses and dehumidifies when humidity is too high, and cools the room when temperature is too high. A dehumidifier can also be used as the humidity control mechanism in this solution.

[0048] Example 3

[0049] This embodiment provides a method for using an expansive soil surface crack testing device under a temperature and humidity controllable boundary, comprising the following steps:

[0050] Step 1: Open the top cover 4 and place the soil sample in the soil sample placement mechanism on the base 1;

[0051] Step 2: After the soil sample is placed, the top cover and the base 1 are installed, and the internal space is kept at a constant temperature and humidity;

[0052] Step 3: Open the processing mechanism to work, repeatedly spray and dry the soil sample, and use a high-definition camera to obtain crack information on the outer surface of the soil sample during this process.

[0053] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantial changes and replacements made by technicians in this field on the basis of the present invention fall within the scope of protection required by the present invention.

Claims

1. An expansive soil surface crack testing device under a temperature and humidity controllable boundary, characterized in that: It includes a constant temperature and humidity chamber, a soil sample placement mechanism in the constant temperature and humidity chamber, and a processing mechanism for spraying and drying the soil sample; The constant temperature and humidity chamber consists of a base and a top cover detachably mounted above the base; The soil sample placement mechanism is provided with a plurality of groups distributed in a circumferential array along the same axis, and the soil sample placement mechanism includes a circular placement table and a rotary drum coaxially arranged outside the placement table, and the placement table is used to place the soil sample; The processing mechanism includes a power assembly and several groups of execution assemblies, wherein the several execution assemblies are respectively installed on each rotary drum, and the power assembly is used to drive the rotary drum to rotate; The outer ring of each rotating drum is provided with a driven gear ring, the power assembly includes a rotating ring rotatably mounted on the base, the outer ring of the rotating ring is provided with a driving outer gear ring, the inner ring of the rotating ring is provided with a driving inner gear ring, the driving inner gear ring is meshed with each driven gear ring, and the driving assembly also includes a driving motor mounted on the base and a driving gear connected to the output shaft of the driving motor, the driving gear is meshed with the driving outer gear ring; The execution assembly includes a support rod fixed to the top surface of the rotary drum, a spray unit and a drying unit installed on the support rod. The support rod is provided with a plurality of grooves on one side close to the soil sample, and a high-definition camera for obtaining image information of the soil sample is installed in each groove. The spray unit includes a water tank fixed on the outside of the support rod, a delivery channel is opened in the support rod, and a plurality of water spray holes 1 and spray holes 2 connected to the delivery channel are distributed in a circumferential array around each groove; Mounting grooves are provided on opposite sides of the groove, and cover plates are slidably provided in the two mounting grooves. The cover plates can close the slots of the corresponding grooves. An electromagnet is provided in the mounting groove, and the cover plates have magnetic attraction, and the inner end of the cover plate is connected to the inner wall of the mounting groove by an elastic recovery mechanism; A slot is provided on one side of the water spray hole one, a positioning rod is movably provided in the slot, and a connecting cavity is provided between the slot and the water spray hole one, a driving wheel is rotatably installed in the connecting cavity, one side of the driving wheel is located in the water spray hole one and can be driven by water flow, a gear ring is provided on the other side of the driving wheel, and is engaged with a gear plate installed on the outside of the positioning rod, one end of the positioning rod can be inserted into the installation slot, and a positioning groove that can cooperate with the end of the positioning rod is provided on the side of the cover plate.

2. The expansive soil surface crack testing device under the temperature and humidity controllable boundary according to claim 1, characterized in that: The drying unit includes a hot air blower installed on a support rod, an air duct opened in the support rod, and blowing hole 1 and blowing hole 2 distributed on the side of the support rod adjacent to the soil sample. Blowing hole 1 and blowing hole 2 are connected to the air duct, and the air inlet of the air duct is connected to the air outlet of the hot air blower.

3. The device for testing surface cracks in expansive soil under a temperature and humidity controllable boundary according to claim 1, characterized in that: An air cavity is provided adjacent to the groove. One side of the air cavity is connected to the air duct through a connecting hole, and the other side of the air cavity is connected to the interior of the installation groove through a plurality of air outlet holes.

4. The device for testing surface cracks in expansive soil under a temperature and humidity controllable boundary according to claim 3, characterized in that: The top cover is made of a transparent material and is in magnetic attraction and sealed contact with the top surface of the base.

5. The method for using the device for testing surface cracks in expansive soil under a temperature and humidity controllable boundary according to any one of claims 1 to 4, characterized in that: The steps include: Step 1: Open the top cover and place the soil sample in the soil sample placement mechanism on the base; Step 2: After the soil sample is placed, the top cover and base are installed to maintain a constant temperature and humidity inside the space; Step 3: Open the processing mechanism to work, repeatedly spray and dry the soil sample, and use a high-definition camera to obtain crack information on the outer surface of the soil sample during this process.

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