Marine facies soft soil triaxial test device

Abstract

The utility model relates to the technical field of geotechnical test instruments, and discloses a marine soft soil triaxial test device which comprises a pressure chamber, an air exhaust assembly and a water supply mechanism, one end of the air exhaust assembly is connected with the top end of the pressure chamber, and the air exhaust assembly comprises a vacuum air pump used for pumping air in the pressure chamber; a confining pressure control pipe is arranged at the bottom of the pressure chamber, the water supply mechanism is detachably connected with the confining pressure control pipe, and water can be injected into the pressure chamber based on the height difference between the water supply mechanism and the pressure chamber and / or vacuum pressure formed in the pressure chamber. And a control valve for controlling the on-off state of the confining pressure control pipe is arranged on the confining pressure control pipe. No residual gas exists in the pressure chamber of the marine facies soft soil triaxial test device provided by the utility model, so that the saturation rate of a marine facies soft soil sample in the pressure chamber is accelerated, meanwhile, disturbance damage to the marine facies soft soil sample is avoided, and the accuracy of test data is improved.

Description

Technical Field

[0001] This utility model relates to the field of geotechnical testing instruments, specifically to a triaxial testing device for marine soft soil. Background Technology

[0002] Marine soft soils are typically characterized by fragility, high void ratio, and high compressibility, exhibiting unique engineering properties that differ significantly from conventional terrestrial soils. In conventional triaxial tests of marine soft soils, the significant impact force generated by the triaxial apparatus pump during the water injection phase of the pressure chamber can cause substantial disturbance and damage to the marine soft soil sample, leading to deviations in the test data. Simultaneously, residual air in the pressure chamber causes the marine soft soil sample to reach saturation more slowly, affecting the test progress.

[0003] In summary, how to address the impact of water injection methods and residual air on marine soft soil samples in triaxial tests has become a pressing issue for those skilled in the art. Utility Model Content

[0004] The purpose of this invention is to overcome the aforementioned problems in the existing technology and to provide a triaxial testing device for marine soft soil.

[0005] To achieve the above objectives, this utility model provides a triaxial testing device for marine soft soil. The triaxial testing device for marine soft soil includes a pressure chamber, an air extraction component, and a water supply mechanism. One end of the air extraction component is connected to the top of the pressure chamber, and the air extraction component includes a vacuum pump for extracting air from the pressure chamber. A confining pressure control pipe is provided at the bottom of the pressure chamber. The water supply mechanism is detachably connected to the confining pressure control pipe and can inject water into the pressure chamber based on the height difference between the water supply mechanism and the pressure chamber and / or the vacuum pressure formed in the pressure chamber. A control valve is provided on the confining pressure control pipe to control its on / off state.

[0006] Preferably, the water supply mechanism includes a water storage tank and a soft water pipe. One end of the soft water pipe extends into the bottom of the water storage tank through the outlet at the top of the water storage tank, and the other end of the soft water pipe is connected to the confining pressure control pipe.

[0007] The water supply system also includes a support structure with adjustable support height, on which the water tank is supported, so that the water level in the water tank can be changed by changing the support height of the support structure.

[0008] Preferably, a sealing ring is installed inside the water outlet to seal the gap between the soft water pipe and the water storage tank at the point where the soft water pipe passes through the water outlet. An air valve is installed on the top of the water storage tank to control the connection between the water storage tank and the outside.

[0009] Preferably, the top periphery of the water storage tank is formed with a seat protruding outward, which is supported on the top of the support structure when the water storage tank is inserted into the support structure from the top of the support structure.

[0010] Preferably, the marine soft soil triaxial test device further comprises a platform, and the support structure comprises a plurality of square supports stacked in a direction perpendicular to the platform.

[0011] The support structure further comprises a plurality of fixing members for detachably connecting the upper and lower square supports, so that the height difference between the bottom surface of the water storage tank and the liquid surface of the pressure chamber can be reduced or increased by changing the number of stacked square supports.

[0012] Preferably, the fixing member comprises a bolt and a nut, the shank of the bolt penetrates the connection between the upper and lower square supports from above or below the connection, and the nut is screwed into the tail end of the shank.

[0013] Preferably, the first support plate and the second support plate are sequentially arranged in the vertical direction of the square support, the center of each of the first support plate and the second support plate is provided with a through hole matched with the outer shape of the water storage tank, the through hole is used for inserting the water storage tank, the square support comprises a plurality of support columns supported between the first support plate and the second support plate.

[0014] Preferably, the edges of the first support plate and the second support plate extend away from the through hole to increase the support area of the first support plate and the second support plate, and the edges of the first support plate and the second support plate are provided with a plurality of fixing holes for the fixing member to pass through.

[0015] Preferably, the air extraction assembly further comprises an air extraction pipe and an air pipe, the air pipe is arranged on the top of the pressure chamber and used for air circulation in the pressure chamber, one end of the air extraction pipe is detachably connected with the air pipe, the other end is connected with the vacuum air pump, and the pressure chamber further comprises an air cover, when the pressure chamber reaches a vacuum state, the air extraction pipe is disconnected with the air pipe, and the air cover is connected with the air pipe to prevent external air from entering the pressure chamber through the air pipe.

[0016] Preferably, the air pipe and the air extraction pipe are connected by threads, and the air pipe is provided with a sealing rubber ring for sealing the connection between the air extraction pipe and the air pipe.

[0017] Through the above technical scheme, the vacuum air pump in the marine soft soil triaxial test device of the utility model extracts the air in the pressure chamber, the water supply mechanism of the device starts to supply water from the bottom of the pressure chamber after the pressure chamber reaches a vacuum state, and the water injection mode of the water supply mechanism generates an impact force much smaller than that generated by the triaxial instrument water pump when injecting water. Therefore, there is no residual gas in the pressure chamber, which accelerates the saturation rate of the marine soft soil sample in the pressure chamber, avoids disturbance and damage to the marine soft soil sample, and improves the accuracy of the test data. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a structural schematic view of the marine soft soil triaxial test device of the utility model.

[0019] BRIEF DESCRIPTION OF DRAWINGS

[0020] 1, pressure machine;2, pressure chamber;201, confining pressure control pipe;202, counter pressure control pipe;203, control valve;3, platform;4, water storage tank;401, water pipe;402, sealing ring;403, clamping seat;5, support structure;501, square support;502, first support plate;503, second support plate;504, strut;505, bolt;506, nut;6, vacuum air pump;601, air suction pipe;602, air pipe. DETAILED DESCRIPTION

[0021] The specific embodiments of the utility model are described in detail below in combination with the drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the utility model, and are not used to limit the utility model.

[0022] The utility model provides a kind of marine soft soil triaxial test device, as Figure 1 As shown in the figure, marine soft soil triaxial test includes pressure chamber 2, air extraction assembly and water supply mechanism, one end of the air extraction assembly is connected with the top end of the pressure chamber 2, and the air extraction assembly includes vacuum air pump 6 for extracting air in pressure chamber 2, the bottom of pressure chamber 2 is equipped with confining pressure control pipe 201, water supply mechanism is detachably connected with the confining pressure control pipe 201, and can give the height difference of the water supply mechanism and pressure chamber 2 and / or vacuum pressure formed in pressure chamber 2 to inject water into the pressure chamber 2, confining pressure control pipe 201 is provided with control valve 203 for controlling its on-off state.

[0023] Through the above technical scheme, the vacuum air pump 6 in the marine soft soil triaxial test device provided by the utility model extracts air in pressure chamber 2, after pressure chamber 2 reaches vacuum state, the water supply mechanism of the device starts to supply water from the bottom of pressure chamber 2, and the water injection mode of water supply mechanism produces impact force far less than that of triaxial instrument water pump when injecting water. Therefore, there is no residual gas in pressure chamber 2, which accelerates the saturation rate of marine soft soil sample in pressure chamber 2, avoids disturbance and damage to marine soft soil sample, and improves the precision of test data.

[0024] The water supply mechanism of the utility model can have any appropriate structure, for example Figure 1In the illustrated embodiment, the water supply mechanism may include a water storage tank 4 and a soft water pipe 401. One end of the soft water pipe 401 extends into the bottom of the water storage tank 4 through the outlet at the top of the water storage tank 4, and the other end of the soft water pipe 401 is connected to the confining pressure control pipe 201. Under the vacuum suction of the pressure chamber 2, the water in the water storage tank 4 flows into the pressure chamber 2 from the bottom through the soft water pipe 401 and the confining pressure control pipe 201.

[0025] Of course, in some other embodiments, a water outlet pipe 401 can be installed on the top of the water storage tank 4, with the tail end of the water outlet pipe 401 extending into the bottom of the water storage tank 4, and the soft water pipe 401 is connected to the top opening of the water outlet pipe 401.

[0026] In this utility model, such as Figure 1 As shown, the water supply mechanism may also include a support structure 5 with adjustable support height, on which the water tank 4 is supported, so that the liquid level in the water tank 4 can be changed by changing the support height of the support structure 5.

[0027] In this invention, after the pressure chamber 2 is evacuated, the water storage tank 4 begins to inject water into the pressure chamber 2 through the soft water pipe 401. At this time, the support structure 5 is used to raise the height of the water storage tank 4 above the pressure chamber 2 to form a height difference between the water storage tank 4 and the pressure chamber 2, thereby accelerating the entry of water from the water storage tank 4 into the pressure chamber 2. After the test, the support structure 5 is disassembled so that the top of the water storage tank 4 is lower than the pressure control port of the pressure chamber 2, so that the water in the pressure chamber 2 can completely flow back into the water storage tank 4.

[0028] In some embodiments, a sealing ring 402 may be provided at the water outlet to seal the gap between the soft water pipe 401 and the water storage tank 4 at the location where the soft water pipe 401 passes through the water outlet.

[0029] In some embodiments, an air valve can be installed on the top of the water storage tank 4. When the pressure chamber 2 starts to draw water from the water storage tank 4, the air valve on the water storage tank 4 is opened to connect the water storage tank 4 to the outside world, so as to avoid the formation of a vacuum area on the top of the water storage tank 4, which would prevent the water in the water storage tank 4 from filling the entire pressure chamber 2. At the same time, the flow rate of water in the water storage tank 4 into the pressure chamber 2 can be adjusted by controlling the flow area of ​​the air valve.

[0030] In some embodiments, a protruding bracket 403 may be formed on the top periphery of the water tank 4. When the water tank 4 is inserted into the top of the support structure 5, the bracket 403 supports the top of the structure. Of course, in other embodiments, the support method between the water tank 4 and the support structure 5 may also be other appropriate methods, which will not be elaborated on here.

[0031] In this invention, the triaxial testing device for marine soft soil may also include a pressure machine 1 and a platform 3. The pressure machine 1, pressure chamber 2, water supply mechanism and air extraction assembly may all be set on the platform 3.

[0032] The support structure 5 of this utility model can have any suitable structure, for example... Figure 1 In the illustrated embodiment, the support structure 5 may include multiple square brackets 501 stacked in a direction perpendicular to the platform 3. The support structure 5 may also include multiple fasteners for detachably fixing the upper and lower layers of square brackets 501 together, so that the height difference between the bottom surface of the water storage tank 4 and the liquid surface of the pressure chamber 2 can be reduced or increased by changing the number of layers of the stacked square brackets 501.

[0033] In this utility model, such as Figure 1 As shown, the fasteners may include bolts 505 and nuts 506. The bolt 505 passes through the connection point from above or below the connection between the upper and lower square brackets 501, while the nut 506 is screwed in from the tail end of the bolt. Of course, in some other embodiments, the fastening method between the upper and lower square brackets 501 may also be a snap-fit ​​engagement, which will not be elaborated upon here.

[0034] The square bracket 501 of this utility model can have any suitable structure, such as Figure 1 As shown, a first support plate and a second support plate 503 can be sequentially arranged along the vertical direction of the square bracket 501. A through hole adapted to the external shape of the water storage tank 4 can be provided at the center of the first support plate 502 and the second support plate 503 for the water storage tank 4 to be inserted.

[0035] The square support 501 may also include multiple support columns 504, which are arranged on the first support plate 502 and the second support plate 503 to provide support force to the square support 501. Each support column 504 may be smaller than the height of the water storage tank 4 to reduce the height and weight of the single-layer square support 501 and facilitate the handling, disassembly and assembly by the test operators.

[0036] Of course, in some other embodiments, the height of the support column 504 can be greater than the height of the water storage tank 4. It is worth noting that in this case, a through hole may not be provided on the second support plate 503.

[0037] In some embodiments, such as Figure 1 As shown, the edges of the first support plate 502 and the second support plate 503 extend away from the through hole to increase the support area of ​​the first support plate 502 and the second support plate 503 and improve the stability of the entire stacked square bracket 501.

[0038] Fixing holes can be provided on the edges of the first support plate 502 and the second support plate 503, such as...Figure 1 As shown, the fasteners pass through the fixing holes on the second support plate 503 of the upper square bracket 501 and the fixing holes on the first support plate 502 of the lower square bracket 501, thereby detachably fixing the upper and lower square brackets 501 together.

[0039] The air extraction component in this invention can have any other suitable structure, such as Figure 1 In the embodiment shown, the air extraction assembly may further include an air extraction pipe 601 and an air pipe 602. The air pipe 602 may be disposed at the top of the pressure chamber 2. One end of the air extraction pipe 601 is detachably connected to the air pipe 602, and the other end is connected to the vacuum pump 6.

[0040] During the evacuation process, the air in the pressure chamber 2 flows into the evacuation pipe 601 through the air pipe 602, and finally enters the vacuum pump 6.

[0041] In some embodiments, the pressure chamber 2 may also include an air cover. After the pressure chamber 2 reaches a vacuum state, the air extraction pipe 601 needs to be removed from the air pipe 602, and the air pipe 602 is connected to the air pipe 602 to prevent outside air from entering the pressure chamber 2 through the air pipe 602.

[0042] Of course, in some other embodiments, a control valve 203 may be provided in the trachea 602 to control the on / off state of the trachea 602.

[0043] In this invention, the air tube 602 and the suction tube 601 can be connected by threads, and a sealing rubber ring is provided inside the air tube 602 to seal the connection between the suction tube 601 and the air tube 602.

[0044] In some embodiments, the soft water pipe 401 may be made of PVC plastic hose, and the air extraction pipe 601 may be made of ordinary plastic hose.

[0045] The various embodiments of this utility model have now been described in detail. To avoid obscuring the concept of this utility model, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0046] Although specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any manner.

Claims

1. A triaxial testing apparatus for marine soft soil, characterized in that, The triaxial test apparatus for marine soft soil includes a pressure chamber (2), an air extraction assembly, and a water supply mechanism. One end of the air extraction assembly is connected to the top of the pressure chamber (2), and the air extraction assembly includes a vacuum pump (6) for extracting air from the pressure chamber (2). A confining pressure control pipe (201) is provided at the bottom of the pressure chamber (2). The water supply mechanism is detachably connected to the confining pressure control pipe (201) and can inject water into the pressure chamber (2) based on the height difference between the water supply mechanism and the pressure chamber (2) and / or the vacuum pressure formed in the pressure chamber (2). A control valve (203) is provided on the confining pressure control pipe (201) for controlling its on / off state. The water supply mechanism includes a water storage tank (4) and a soft water pipe (401). One end of the soft water pipe (401) extends into the bottom of the water storage tank (4) through the outlet at the top of the water storage tank (4), and the other end of the soft water pipe (401) is connected to the confining pressure control pipe (201). The water supply mechanism also includes a support structure (5) with adjustable support height, on which the water storage tank (4) is supported, so that the liquid level of the water storage tank (4) can be changed by changing the support height of the support structure (5).

2. The triaxial testing apparatus for marine soft soil according to claim 1, characterized in that, A sealing ring (402) is provided inside the water outlet to seal the gap between the soft water pipe (401) and the water storage tank (4) at the position where the soft water pipe (401) passes through the water outlet. An air valve is provided on the top of the water storage tank (4) to control the connection between the water storage tank (4) and the outside.

3. The triaxial testing apparatus for marine soft soil according to claim 1, characterized in that, The top periphery of the water tank (4) has an outwardly protruding bracket (403). When the water tank (4) is inserted into the support structure (5) from the top, the bracket (403) is supported on the top of the support structure (5).

4. The triaxial testing apparatus for marine soft soil according to claim 1, characterized in that, The marine soft soil triaxial test device also includes a platform (3), and the support structure (5) includes multiple square supports (501) stacked in a direction perpendicular to the platform (3). The support structure (5) also includes a number of fasteners for detachably fixing the upper and lower square brackets (501) together so that the height difference between the bottom surface of the water storage tank (4) and the liquid surface of the pressure chamber (2) can be reduced or increased by changing the number of layers of the square brackets (501).

5. The triaxial testing apparatus for marine soft soil according to claim 4, characterized in that, The fastener includes a bolt (505) and a nut (506). When the bolt (505) passes through the connection between the upper and lower square brackets (501) from above or below, the nut (506) is screwed in from the tail end of the bolt.

6. The triaxial testing apparatus for marine soft soil according to claim 4, characterized in that, A first support plate (502) and a second support plate (503) are sequentially arranged along the vertical direction of the square bracket (501). The center of the first support plate (502) and the second support plate (503) are provided with through holes that are adapted to the external shape of the water storage tank (4). The through holes are used for the water storage tank (4) to be inserted. The square bracket (501) includes a plurality of pillars (504), which are supported between the first support plate (502) and the second support plate (503).

7. The triaxial testing apparatus for marine soft soil according to claim 6, characterized in that, The edges of the first support plate (502) and the second support plate (503) extend away from the through hole to increase the support area of ​​the first support plate (502) and the second support plate (503). The edges of the first support plate (502) and the second support plate (503) are provided with a plurality of fixing holes for the fasteners to pass through.

8. The triaxial testing apparatus for marine soft soil according to claim 1, characterized in that, The air extraction assembly also includes an air extraction pipe (601) and an air pipe (602). The air pipe (602) is located at the top of the pressure chamber (2) for air circulation within the pressure chamber (2). One end of the air extraction pipe (601) is detachably connected to the air pipe (602), and the other end is connected to the vacuum pump (6). The pressure chamber (2) also includes an air cover. When the pressure chamber (2) reaches a vacuum, the air extraction pipe (601) is disconnected from the air pipe (602), and the air cover is connected to the air pipe (602) to prevent outside air from entering the pressure chamber (2) through the air pipe (602).

9. The triaxial testing apparatus for marine soft soil according to claim 8, characterized in that, The air pipe (602) and the suction pipe (601) are connected by threads. A sealing rubber ring is provided inside the air pipe (602) to seal the connection between the suction pipe (601) and the air pipe (602).

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