Fine-grained soil in-situ permeability test equipment and permeability coefficient determination method

Abstract

The invention discloses fine-grained soil in-situ permeability test equipment and a permeability coefficient determination method.The fine-grained soil in-situ permeability test equipment comprises a base, an adjusting sliding base is arranged at the upper end of the base in a sliding mode, a vertical sliding base is arranged above the adjusting sliding base and connected with a lifting mechanism, a rotating shaft rotating horizontally is arranged on the vertical sliding base, and a fixed base is arranged at the end of the rotating shaft; the outer side of the fixed base is connected with a rotating cylinder through a rotating outer ring, the two ends of the rotating cylinder are of opening structures, the upper end of the rotating cylinder is connected with a drilling cutter set used for drilling through a connecting frame, a rotating driving piece used for driving the rotating cylinder to rotate is arranged on the fixed base, and the rotating cylinder is connected with a water supply mechanism. All the components interact with one another, an in-situ permeability test of the fine-grained soil is carried out, and the permeability coefficient is measured. The problems that in the prior art, the permeability coefficient measuring process is not convenient enough, and measured data are not real enough are solved. And after the test is completed, the device can be quickly moved to the next test target position by utilizing the maneuverability of the device, so that the test efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of geotechnical tests for water conservancy and hydropower engineering, and specifically relates to in-situ permeability test equipment for fine-grained soil, and also relates to an in-situ permeability coefficient determination method for fine-grained soil. Background Art

[0002] In order to evaluate the permeability characteristics of engineering soil, it is often necessary to measure the permeability characteristics of the soil in the area on site to ensure the safety of construction. The existing on-site permeability coefficient measurement for fine-grained soil is more reliable with the pumping and water injection methods. Among them, the double-ring water injection method and the single-ring water injection method are the most widely used methods in current engineering. They are suitable for soils with shallow test depths, but the effect is not good for soils with large test depths. Although the two test methods can better measure the permeability coefficient of soils with shallow test depths, they are not convenient to operate. Each time a position is measured, a test pit needs to be dug, which consumes a lot of manpower. The debris on the surface of the test soil that is inconvenient to clean can also easily affect the permeability characteristics of the soil. At the same time, the test devices of the two methods need to manually control the switch of the valve to keep the injected water level unchanged, which is inconvenient to control and will also make the measurement results inaccurate and have large errors.

[0003] The existing patent announcement number CN117451593B discloses a soil seepage detection device for geotechnical engineering. Although the device can perform seepage detection on the soil layer, the detection here only stays at the depth of the shallower soil layer, and the shallower soil layer is loose. This detection is not accurate, and generally construction engineering operations require foundation pits to be dug, so the detection results of the shallow soil layer cannot truly reflect the actual data underground.

[0004] Based on the above problems, an in-situ permeability test device for fine-grained soil and a method for determining permeability coefficient are now provided, which can reduce or even eliminate the impact of the shortcomings of existing devices on the test results. Summary of the invention

[0005] The purpose of the present invention is to provide an in-situ permeability test device for fine-grained soil and a permeability coefficient measuring device, which solves the problems in the prior art that the measuring process is not convenient enough and the measuring data is not authentic enough.

[0006] The present invention also aims to provide a method for measuring the in-situ permeability coefficient of fine-grained soil.

[0007] The first technical solution adopted by the present invention is: an in-situ infiltration test equipment for fine-grained soil, including a base, a walking wheel for walking is provided on the outer side of the base, an adjusting slide is slidably provided on the upper end of the base, the adjusting slide is connected to a horizontal adjusting member for driving its horizontal movement, a vertical slide is provided above the adjusting slide, the vertical slide is connected to a lifting mechanism for driving its up and down movement, a rotating shaft is provided on the vertical slide for horizontal rotation, a fixed base is provided at the end of the rotating shaft, the end of the fixed base is connected to a steering adjusting member for driving its rotation, a rotating outer ring is provided on the outer side of the fixed base, a rotating cylinder is rotatably provided on the rotating outer ring, both ends of the rotating cylinder are open structures, and one end of the rotating cylinder is connected to a drilling tool group for drilling holes through a connecting frame, a rotating driving member for driving the rotating cylinder to rotate is provided on the fixed base, and a water supply mechanism for providing water to the interior thereof is provided on the rotating cylinder.

[0008] The present invention is also characterized in that: Preferably, the measuring port of the rotating drum is provided with a water receiving ring for receiving water, and a plurality of overflow ports are provided on the inner side of the water receiving ring.

[0009] Preferably, a simple liquid level gauge for detecting the liquid level height can be placed inside the rotating drum. One end of the sensor of the digital simple liquid level gauge is placed inside the rotating drum through the opening of the connecting frame, and the digital display instrument panel can display the water level in the rotating drum in real time.

[0010] Preferably, the water supply mechanism includes a water guide cavity arranged inside the rotating outer ring, the rotating outer ring is connected to the inner cavity of the rotating cylinder through a plurality of water inlet ports, the water inlet end of the rotating outer ring is movably connected to the connecting side pipe, the connecting side pipe is movably connected to the cache inner ring, and the cache inner ring is coaxially movably sleeved on the outside of the rotating shaft. A cache outer ring is fixedly and sealedly connected to the outside of the cache inner ring, the cache outer ring and the cache inner ring are connected through a plurality of connecting ports, the water inlet end of the cache outer ring is connected to the water supply pump through a water supply pipe, the water pumping end of the water supply pump extends to the inside of the water tank, the water tank is fixedly arranged outside the vertical slide seat, a water inlet is provided above the water tank, a water outlet is provided below the water tank, and a scaled observation bar is provided on one side of the water tank.

[0011] Preferably, the rotary driving member includes a driven gear disposed outside the rotating cylinder, one side of the driven gear is meshed with the driving gear, and the driving gear is connected to a rotary motor for driving the driven gear to rotate.

[0012] Preferably, the steering adjustment member comprises a steering worm wheel arranged at the end of the rotating shaft, the upper side of the steering worm wheel is meshed with the steering worm, and the end of the steering worm is connected to a steering motor for driving the steering worm to rotate.

[0013] Preferably, the lifting mechanism includes vertical sliding sleeves symmetrically arranged at both ends of the vertical slide, a vertical sliding rod is slidably provided in the vertical sliding sleeve, the lower end of the vertical sliding rod is connected and fixed to the adjusting slide, the upper ends of the two vertical sliding sleeves are connected by a transverse frame, the side of the vertical slide is connected to the lifting thread block by a U-shaped frame, a lifting screw is threadedly provided in the lifting thread block, the upper end of the lifting screw is rotatably connected to the auxiliary side block on the transverse frame, the lower end of the lifting screw is connected to a lifting motor for driving it to rotate, and the lifting motor is fixedly arranged on a motor seat outside the adjusting slide.

[0014] Preferably, the horizontal adjustment member includes horizontal sliding holes symmetrically arranged on both sides of the adjusting slide, a horizontal guide rod is slidably provided in each horizontal sliding hole, both ends of the horizontal guide rod are connected to the upper end of the base through a fixed block, an adjusting screw is threadedly provided in the middle position of the adjusting slide, one end of the adjusting screw is rotatably connected to the bearing block on the base, and the other end of the adjusting screw is connected to an adjusting motor for driving it to rotate.

[0015] The second technical solution adopted by the present invention is: a method for measuring the in-situ permeability coefficient of fine-grained soil, which specifically includes the following steps: Step 1: Determine the cross-sectional area of ​​the water tank S (cm 2 ), and the cross-sectional area of ​​the rotating drum port excluding the water ring A (cm 2 ).

[0016] Step 2: Level the ground within the target position of the measuring point. Move the base to the target position of the measuring point, and then use the horizontal adjustment piece to drive the adjustment slide to slide to the target position of the measuring point, separate the connecting side pipe from the water inlet end of the rotating outer ring, and then use the steering adjustment piece to drive the rotating shaft to rotate, so that the drilling cutter group drills vertically downward to the depth of the test soil layer, and avoid disturbing the surrounding soil during the drilling process; Step 3: Then drive the rotating shaft to rotate through the steering adjustment part, so that the test end of the rotating cylinder is set downward, so that the end of the rotating cylinder fits the size of the drill pit and penetrates to the test depth, and the rotating drive part rotates to make the end of the rotating cylinder fit more closely with the ground in the drill pit.

[0017] Step 4: Pour the weighed water into the water tank through the water inlet, place a thermometer into the water tank from the water inlet, flexibly connect the connecting side pipe to the water inlet end of the rotating outer ring, start the water supply pump, and fill the rotating cylinder with water. According to the water level displayed by the simple liquid level gauge placed inside the rotating cylinder and the water supply pump switch, ensure that the water level in the rotating cylinder remains unchanged at a certain depth. During the process, water must be added to the water tank in time, and the water level scale value in the water tank must be recorded before and after each water addition. Record the start time of water seepage and the water temperature in the water tank. After a certain period of time, use the observation bar on the water tank to determine whether the water flow rate that infiltrates the soil from the water tank is stable during this time. The basis for judgment is that the difference in the height of the water level drop in the same adjacent time period does not exceed 0.5cm.

[0018] Step 5: After the water outflow from the water tank reaches a stable level, measure the water outflow 6 times in the same time period within 2 hours and take the average value. The difference between the seepage flow rate measured each time and the average seepage flow rate should not exceed 10%. If the difference between the seepage flow rate measured at a certain time and the average seepage flow rate exceeds 10%, it should be discarded and the discarded seepage flow rate should be re-measured. Q =S×h ,in h It is the height (cm) of water level drop during the measuring time period after the flow rate stabilizes.

[0019] Step 6: After the test of this measuring point is completed, turn off the water supply pump, pull out the rotating cylinder, and suck out the water in the drill pit. Push the equipment to the target position of the next measuring point and repeat steps 2, 3, 4 and 5.

[0020] Step 7: After the test is completed, calculate the approximate permeability coefficient of the test soil according to the following formula :

[0021]

[0022] Q -Average water flow rate (cm 3 ); t -Measurement time (s); A - The cross-sectional area of ​​the rotating cylinder (200) port excluding the water ring (cm 2 ); , - are the hydrodynamic viscosity coefficients at the water temperature and 20°C during the measurement period (1×10 -6 kPa·s), The relationship with temperature can be obtained by looking up relevant information.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention is designed according to existing needs. A test pit of corresponding depth can be dug on the ground according to actual needs. There is no need to manually dig the test pit, which improves the convenience of operation. Carrying out the test in the test pit eliminates the influence caused by loose surface soil and ensures the accuracy of the test. The pressing end of the rotating cylinder can also be driven to rotate to ensure the sealing of the docking position of the rotating cylinder, further ensuring the quality of the test. The water receiving ring and overflow hole are also provided to avoid high water level impacting the soil, making the test more accurate. After the test is completed, the mobility of the device can be used to quickly move to the next test target position, improving the test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0025] Figure 1 It is a schematic diagram of the structure of one side of the present invention.

[0026] Figure 2 It is a structural schematic diagram of another side of the present invention.

[0027] Figure 3 It is a schematic diagram of the lower structure of the present invention.

[0028] Figure 4 It is a schematic diagram of the internal structure of the present invention.

[0029] Figure 5 For the present invention Figure 4 Schematic diagram of the structure of A.

[0030] Figure 6 For the present invention Figure 4 Schematic diagram of the structure of B.

[0031] In the figure, 100. base, running wheels 101; 200. rotating cylinder, 201. connecting side pipe, 202. rotating shaft, 203. rotating outer ring, 204. water outlet, 205. water inlet, 206. connecting frame, 207. water tank, 208. drilling tool group, 209. water supply pump, 210. buffer outer ring, 211. buffer inner ring, 212. driving gear, 213. water inlet port, 214. driven gear, 215. rotating motor, 216. fixed base, 217. overflow port, 218. water receiving ring, 219. connecting port, 220. observation strip; 300. Adjusting slide, 301. Horizontal guide rod, 302. Adjusting motor, 303. Vertical slide, 304. Vertical sliding sleeve, 305. Vertical slide rod, 306. Transverse frame, 307. Steering worm gear, 308. Steering worm, 309. Steering motor, 310. Auxiliary side block, 311. Lifting thread block, 312. U-shaped frame, 313. Lifting screw, 314. Lifting motor, 315. Adjusting screw. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Example 1 like Figure 1-Figure 6 As shown, the embodiment of the present invention provides an in-situ permeability test device for fine-grained soil, including a base 100, a walking wheel 101 for walking is arranged on the outer side of the base 100, an adjusting slide 300 is slidably arranged on the upper end of the base 100, the adjusting slide 300 is connected to a horizontal adjustment member for driving its horizontal movement, a vertical slide 303 is arranged above the adjusting slide 300, the vertical slide 303 is connected to a lifting mechanism for driving its up and down movement, a rotating shaft 202 is arranged on the vertical slide 303 for horizontal rotation, and a rotating shaft 202 is arranged at the end thereof A fixed base 216, the end of which is connected to a steering adjustment member for driving its rotation, a rotating outer ring 203 is provided on the outside of the fixed base 216, a rotating cylinder 200 is rotatably provided on the rotating outer ring 203, both ends of the rotating cylinder 200 are open structures, and one end of the rotating cylinder 200 is connected to a drilling cutter group 208 for drilling holes through a connecting frame 206, a rotating driving member for driving the rotating cylinder 200 to rotate is provided on the fixed base 216, and a water supply mechanism for providing water to the inside of the rotating cylinder 200 is provided on the rotating cylinder 200. The base 100 is a frame type, and the area corresponding to the rotating cylinder 200 is hollowed out, so that the rotating cylinder 200 can move up and down under the drive of the lifting mechanism and contact the ground; when one end of the drilling cutter group 208 is perpendicular to the ground and downward, a test pit can be drilled in the soil layer, and when the end of the rotating cylinder 200 used for testing is pressed against the soil at the bottom of the test pit, water of a predetermined water level is injected into the rotating cylinder 200, so as to measure the permeability coefficient of the soil.

[0034] Example 2 Based on Example 1, The measuring port of the rotating drum 200 is provided with a water receiving ring 218 for receiving water, and a plurality of overflow ports 217 are provided inside the water receiving ring 218, so that when water flows out along the water inlet port 213, it will be received by the water receiving ring 218, so as to prevent water from impacting the soil and affecting the test results; A simple liquid level gauge for detecting the liquid level height can be placed inside the rotating drum 200, so that the staff can observe the water level in the rotating drum 200. One end of the sensor of the digital simple liquid level gauge is placed inside the rotating drum 200 through the opening of the connecting frame 206, and the digital display instrument panel is placed outside the rotating drum, which can display the water level in the rotating drum 200 in real time.

[0035] The water supply mechanism includes a water guiding cavity arranged inside the rotating outer ring 203. The rotating outer ring 203 is connected to the inner cavity of the rotating cylinder 200 through multiple water inlet ports 213. The water inlet end of the rotating outer ring 203 is movably connected to the connecting side tube 201. The connecting side tube 201 is movably connected to the cache inner ring 211. The cache inner ring 211 is coaxially movably sleeved on the outside of the rotating shaft 202 without affecting the rotation of the rotating shaft 202. The outer side of the cache inner ring 211 is fixedly sealed and connected to a cache outer ring 210. The cache outer ring 210 and the cache inner ring 211 are connected through multiple connecting ports 219. The water inlet end of the cache outer ring 210 is connected to the water supply pump 209 through a water supply pipe. The pumping end of the water supply pump 209 extends to the inside of the water tank 207. The water tank 207 is fixedly arranged on the outer side of the vertical slide 303. There is a water inlet 205 on the top of the water tank 207 and a water outlet 204 on the bottom of the water tank. An observation bar 220 with scales is arranged on one side of the water tank 207. The water level in the water tank can be observed through the observation bar 220, and water can be added to the water tank 207 in time. It is worth noting that the connecting side pipe 201 is movably connected with the water inlet end of the rotating outer ring 203 and the cache inner ring 211 respectively. By separating the connecting side pipe 201 from the water inlet end of the rotating outer ring 203 and the cache inner ring 211 respectively, the steering interference problem caused by the operation of the steering adjustment member can be avoided. The water in the water tank 207 is sent into the interior of the cache outer ring 210 through the water supply pump 209, and the water enters the cache inner ring 211 through the connecting port 219. Then the water in the cache inner ring 211 enters the rotating outer ring 203 along the connecting side pipe 201, and finally enters the inner cavity of the rotating cylinder 200 along the water inlet port 213. Sealing measures are taken at the interface connections of the components involved in the entire water guiding process to ensure that water does not leak out.

[0036] Example 3 On the basis of Example 1 and Example 2, The rotary drive member includes a driven gear 204 disposed outside the rotating cylinder 200, one side of the driven gear 204 is meshed with a driving gear 212, and the driving gear 212 is connected to a rotating motor 215 for driving the driving gear 212 to rotate. Under the drive of the rotating motor 215, the driving gear 212 drives the driven gear 204 to rotate, and the driven gear 204 drives the rotating cylinder 200 to rotate, thereby providing power for the drilling cutter group 208 to drill holes, and also making the other end of the rotating cylinder 200 fit better with the ground, avoiding the problem of a gap at the docking position; The steering adjustment member includes a steering worm wheel 307 disposed at the end of the rotating shaft 202. The upper side of the steering worm wheel 307 is meshed with a steering worm 308. The end of the steering worm 308 is connected to a steering motor 309 for driving the steering worm 308 to rotate. Driven by the steering motor 309, the steering worm 308 matches the steering worm wheel 307, thereby driving the rotating shaft 202 to rotate and providing power for the rotation of the rotating shaft 202. After solving the problem of component interference, the steering worm wheel 307 cooperates with the steering worm 308 to rotate the rotating cylinder 200, and the rotation angle can reach 360°; The lifting mechanism includes vertical sleeves 304 symmetrically arranged at both ends of the vertical slide 303, a vertical slide rod 305 is slidably arranged in the vertical sleeve 304, the lower end of the vertical slide rod 305 is connected and fixed to the adjusting slide 300, the upper ends of the two vertical sleeves 304 are connected by a horizontal frame 306, the side of the vertical slide 303 is connected to the lifting thread block 311 by a U-shaped frame 312, a lifting screw 313 is threadedly provided in the lifting thread block 311, the upper end of the lifting screw 313 is rotatably connected to the auxiliary side block 310 on the horizontal frame 306, the lower end of the lifting screw 313 is connected to a lifting motor 314 for driving it to rotate, and the lifting motor 314 is fixedly arranged on the motor seat outside the adjusting slide 300. Driven by the lifting motor 314, the lifting screw 313 and the lifting thread block 311 rotate relative to each other. Under the action of the thread, the lifting thread block 311 drives the vertical slide 303 to slide up and down along the vertical slide rod 305, so that the floating height of the vertical slide 303 can be adjusted. The horizontal adjustment member includes horizontal sliding holes symmetrically arranged on both sides of the adjustment slide 300, and a horizontal guide rod 301 is slidably arranged in each horizontal sliding hole. The two ends of the horizontal guide rod 301 are connected to the upper end of the base 100 through a fixed block. An adjustment screw 315 is threadedly arranged in the middle position of the adjustment slide 300. One end of the adjustment screw 315 is rotatably connected to the bearing block on the base 100, and the other end of the adjustment screw 315 is connected to the adjustment motor 302 for driving the rotation thereof. Driven by the adjustment motor 302, the adjustment screw 315 rotates relative to the adjustment slide 300. Under the action of the thread, the adjustment slide 300 can slide horizontally along the horizontal guide rod 301, thereby adjusting the test position.

[0037] Example 4 The in-situ permeability coefficient determination method of fine-grained soil of the present invention has the following specific operating steps: Step 1: Calibrate the cross-sectional area of ​​the water tank 207 S (cm 2 ), and the cross-sectional area of ​​the rotating cylinder 200 port excluding the water ring A (cm 2 ).

[0038] Step 2: Level the ground within the target position of the measuring point. Move the base 100 to the target position of the measuring point, and then drive the adjustment slide 300 to slide to the target position of the measuring point through the horizontal adjustment member, separate the connecting side pipe 201 from the water inlet end of the rotating outer ring 203, and then drive the rotating shaft 202 to rotate through the steering adjustment member, so that the drilling cutter group 208 drills vertically downward to the depth of the test soil layer, and avoid disturbing the surrounding soil during the drilling process; Step 3: Then, the rotating shaft 202 is rotated by the steering adjustment member, so that the test end of the rotating cylinder 200 is set downward, so that the end of the rotating cylinder 200 fits the size of the drill hole and penetrates to the test depth, and the rotating drive member is rotated to make the end of the rotating cylinder 200 fit more closely with the ground in the drill hole. Place one end of the sensor of the digital display simple liquid level meter into the rotating cylinder 200 through the opening of the connecting frame, and turn on the liquid level meter to start working.

[0039] Step 4: Pour the weighed water into the water tank 207 through the water inlet 205, place a thermometer into the water tank 207 from the water inlet 205, flexibly connect the connecting side pipe 201 with the water inlet end of the rotating outer ring 203, start the water supply pump 209, and send the water in the water tank 207 into the interior of the cache outer ring 210. The water enters the cache inner ring 211 through the connecting port 219, and then the water in the cache inner ring 211 enters the rotating outer ring 203 along the connecting side pipe 201, and finally enters the inner cavity of the rotating cylinder 200 along the water inlet port 213. When the water flows out along the water inlet port 213, it will be caught by the water receiving ring 218 to prevent water from impacting the soil and affecting the test results. Sealing measures are taken at the interface connections of the components involved in the entire water conduction process to ensure that water does not seep out. According to the water level displayed by the simple liquid level gauge in the rotating drum 200 and the switch of the water supply pump 209, ensure that the water level in the rotating drum 200 remains unchanged at a certain depth. During the process, water must be added to the water tank 207 in time, and the water level scale value in the water tank 207 before and after each water addition is recorded. Record the start time of water seepage and the water temperature in the water tank 207. After a certain period of time, judge whether the water flow rate infiltrating into the soil from the water tank 207 is stable during this time through the observation bar 220 on the water tank. The judgment basis is that the difference in the height of the water level drop in the adjacent same time period does not exceed 0.5cm.

[0040] Step 5: After the water outflow from the water tank 207 reaches a stable state, measure the water outflow 6 times in the same time period within 2 hours and take the average value. The difference between the seepage flow rate measured each time and the average seepage flow rate should not exceed 10%. If the difference between the seepage flow rate measured at a certain time and the average seepage flow rate exceeds 10%, it should be discarded and the discarded seepage flow rate should be re-measured. Q=S×h ,in h It is the height (cm) of water level drop during the measuring time period after the flow rate stabilizes.

[0041] Step 6: After the test of the measuring point is completed, turn off the water supply pump 209, pull out the rotating cylinder 200, and suck out the water in the drill hole. Push the device to the next measuring point target position, and repeat steps 2, 3, 4 and 5.

[0042] Step 7: After the test is completed, calculate the approximate permeability coefficient of the test soil.

[0043] Example 5 Based on Example 4, in step 7, the approximate permeability coefficient of the test soil is calculated according to the following formula: :

[0044]

[0045] Q -Average water flow rate (cm 3 ); t -Measurement time (s); A - The cross-sectional area of ​​the rotating cylinder (200) port excluding the water ring (cm 2 ); , - are the hydrodynamic viscosity coefficients at the water temperature and 20°C during the measurement period (1×10 -6 kPa·s), The relationship with temperature can be obtained by looking up relevant information.

[0046] Example 6 For a sandy soil site, only one in-situ permeability test is required for the sandy soil. According to step 1 above, the cross-sectional area of ​​the water outlet tank 207 is calibrated to 600 cm 2 , and the cross-sectional area of ​​the rotating cylinder 200 port minus the water ring is 200cm 2; According to step two, drill holes at the target location of the measuring point to a depth of the test soil layer, avoiding disturbance of the surrounding soil during the drilling process; according to step three, fit the end of the rotating cylinder 200 tightly against the ground in the drill pit. According to step four, add water to the inside of the rotating cylinder 200 to keep the water level in the rotating cylinder 200 unchanged. The start time of water seepage is recorded as 10:00 am and the water temperature in the water tank 207 is 25°C. From 11:00 am, the difference in the water level drop observed by the observation bar 220 on the water tank in the adjacent same time intervals thereafter does not exceed 0.5 cm, thereby determining that the water flow rate from the water tank 207 into the soil has stabilized. According to step five, after the water flow rate stabilizes, the water level drop heights in the water tank every 10 minutes measured within 2 hours are 2.0 cm, 1.8 cm, 1.8 cm, 2.0 cm, 1.7 cm, and 1.7 cm, respectively. Based on the seepage flow rate Q=S×h , the seepage flow rate is calculated Q 1 = 1200 cm 3 , Q 2 = 1080cm 3 , Q 3 = 1080cm 3 , Q 4 = 1200cm 3 , Q 5 = 1020cm 3 , Q 6 = 1020cm 3 , the average value Q’= ( Q 1 +Q + Q 3 +Q + Q 5 +Q 6) / 6=1100cm 3 After comparison, the seepage flow rate of 6 measurements and the average seepage flow rate Q’ The difference does not exceed 10%, so the average of the seepage flow rates of the six measurements is taken as the seepage flow rate of this test. According to step 6, after the test of the measuring point is completed, the water supply pump 209 is turned off, the rotating cylinder 200 is pulled out, and the water in the drill pit is sucked out. According to step 7, it can be calculated = cm / s=9.17×10 -3 cm / s; = 9.17 × 10 -3 ×0.890 cm / s=8.16×10 -3cm / s (25℃ for The value is 0.890), so the permeability coefficient of the sandy soil site is 8.16×10 -3 cm / s.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. Fine-grained soil in-situ permeability test equipment, characterized by: The invention comprises a base (100), wherein an adjusting slide (300) is slidably connected to the upper end of the base (100), and the adjusting slide (300) is connected to a horizontal adjusting member for driving the adjusting slide (300) to move horizontally, and is characterized in that: a vertical slide (303) is provided above the adjusting slide (300), and the vertical slide (303) is connected to a lifting mechanism, and a rotating shaft (202) is provided on the vertical slide (303) for horizontal rotation, and a fixed base (216) is provided at the end of the rotating shaft (202), and the fixed base (216) is provided on the vertical slide (303). The end of the seat (216) is connected to the steering adjustment member, a rotating outer ring (203) is provided on the outside of the fixed base (216), a longitudinal rotating cylinder (200) is rotatably connected to the rotating outer ring (203), both ends of the rotating cylinder (200) are open structures, the upper end of the rotating cylinder (200) is connected to the drilling tool group (208) via a connecting frame (206), a rotating driving member for driving the rotating cylinder (200) to rotate is provided on the fixed base (216), and the rotating cylinder (200) is connected to a water supply mechanism.

2. The fine-grained soil in-situ permeability test equipment according to claim 1 is characterized in that: The rotating cylinder (200) is provided with a measuring port on its wall, a water receiving ring (218) for receiving water is provided at the measuring port, and a plurality of overflow ports (217) are provided on the inner side of the water receiving ring (218); and running wheels (101) for running are provided on the outer side of the base (100).

3. The fine-grained soil in-situ permeability test equipment according to claim 1 is characterized in that: A digital simple liquid level gauge is arranged in the rotating cylinder (200), and one end of a sensor of the digital simple liquid level gauge is placed into the rotating cylinder (200) through the opening of the connecting frame (206), and a digital display instrument panel is arranged outside the rotating cylinder (200) to display the water level in real time.

4. The fine-grained soil in-situ permeability test equipment according to claim 1 is characterized in that: The water supply mechanism comprises a water guide cavity arranged inside a rotating outer ring (203); the rotating outer ring (203) is connected to the inner cavity of the rotating drum (200) via a plurality of water inlet ports (213); the water inlet end of the rotating outer ring (203) is movably connected to a connecting side pipe (201); the connecting side pipe (201) is movably connected to a cache inner ring (211); the cache inner ring (211) is coaxially movably sleeved on the outside of the rotating shaft (202); the outside of the cache inner ring (211) is fixedly and sealedly connected to a cache outer ring (210); the cache outer ring (211) is fixedly and sealedly connected to a cache outer ring (210); the cache inner ... The ring (210) and the cache inner ring (211) are connected via a plurality of connecting ports (219); the water inlet end of the cache outer ring (210) is connected to the water supply pump (209) via a water supply pipe; the water pumping end of the water supply pump (209) extends to the inside of the water tank (207); the water tank (207) is fixedly arranged on the outside of the vertical slide seat (303); a water inlet (205) is provided on the top of the water tank (207); a water outlet (204) is provided on the bottom of the water tank (207); and an observation bar (220) with a scale is provided on one side of the water tank (207).

5. The fine-grained soil in-situ permeability test equipment according to claim 4, characterized in that: The rotary drive member comprises a driven gear (214) arranged outside the rotary cylinder (200); one side of the driven gear (214) is meshed with a driving gear (212); and the driving gear (212) is connected to a rotary motor (215).

6. The fine-grained soil in-situ permeability test equipment according to claim 4 is characterized in that: The steering adjustment member comprises a steering worm wheel (307) arranged at the end of the rotating shaft (202); the upper side of the steering worm wheel (307) is meshed with a steering worm (308); and the end of the steering worm (308) is connected to a steering motor (309).

7. The fine-grained soil in-situ permeability test equipment according to claim 4 is characterized in that: The lifting mechanism comprises vertical sliding sleeves (304) symmetrically arranged at two ends of a vertical slide seat (303), a vertical sliding rod (305) being slidably arranged in the vertical sliding sleeves (304), the lower end of the vertical sliding rod (305) being connected and fixed to the adjusting slide seat (300), the upper ends of the two vertical sliding sleeves (304) being connected via a transverse frame (306), the side of the vertical slide seat (303) being connected to a lifting thread block (311) via a U-shaped frame (312), a lifting screw rod (313) being threadedly arranged in the lifting thread block (311), the upper end of the lifting screw rod (313) being rotatably connected to an auxiliary side block (310) on the transverse frame (306), the lower end of the lifting screw rod (313) being connected to a lifting motor (314) for driving the lifting screw rod (313) to rotate, and the lifting motor (314) being fixedly arranged on a motor seat outside the adjusting slide seat (300).

8. The fine-grained soil in-situ permeability test equipment according to claim 4, characterized in that: The horizontal adjustment member comprises horizontal sliding holes symmetrically arranged on both sides of the adjustment slide (300), a horizontal guide rod (301) being slidably arranged in each horizontal sliding hole, two ends of the horizontal guide rod (301) being connected to the upper end of the base (100) via a fixing block, an adjustment screw rod (315) being threadedly arranged in the middle position of the adjustment slide (300), one end of the adjustment screw rod (315) being rotatably connected to a bearing block on the base (100), and the other end of the adjustment screw rod (315) being connected to the adjustment motor (302).

9. A method for determining the in-situ permeability coefficient of fine-grained soil, characterized in that: The fine-grained soil in-situ permeability test equipment according to any one of claims 1 to 8 is used, and specifically comprises the following steps: Step 1: Calibrate the cross-sectional area of ​​the water outlet tank (207) S , and the cross-sectional area of ​​the rotating cylinder (200) port excluding the water receiving ring A ; Step 2: Level the ground within the target position of the measuring point; move the base (100) to the target position of the measuring point, then drive the adjusting slide (300) to slide to the target position of the measuring point through the horizontal adjustment member, separate the connecting side pipe (201) from the water inlet end of the rotating outer ring (203), and then drive the rotating shaft (202) to rotate through the steering adjustment member, so that the drilling cutter group (208) drills vertically downward to a depth of the test soil layer, and avoids disturbing the surrounding soil during the drilling process; Step 3: Then, the rotating shaft (202) is driven to rotate by the steering adjustment member, so that the test end of the rotating cylinder (200) faces downward, so that the end of the rotating cylinder (200) fits into the drill hole and penetrates to the test depth, and the rotating driving member is rotated so that the end of the rotating cylinder (200) fits more closely with the ground in the drill hole; Step 4: Pour the weighed water into the water tank (207) through the water inlet (205), place a thermometer from the water inlet (205) into the water tank (207), flexibly connect the connecting side pipe (201) to the water inlet end of the rotating outer ring (203), start the water supply pump (209), and fill water into the rotating drum (200); according to the water level displayed by the simple liquid level gauge placed inside the rotating drum (200) and the switch of the water supply pump (209), ensure that the rotating drum (200) is filled with water. The water level is maintained at a predetermined water level. During the process, water must be added to the water tank (207) in a timely manner, and the water level scale value in the water tank (207) before and after each water addition is recorded; the start time of water seepage and the water temperature in the water tank (207) are recorded; after a certain period of time, the observation bar (220) on the water tank (207) is used to determine whether the water flow rate from the water tank (207) into the soil during this period is stable, and the determination is based on the difference in the height of the water level drop within the same adjacent time period not exceeding 0.5 cm; Step 5: After the water outflow from the water tank (207) reaches a stable state, measure the water outflow 6 times in the same time period within 2 hours and take the average value. The difference between the seepage flow rate measured each time and the average seepage flow rate shall not exceed 10%. If the difference between the seepage flow rate measured at a certain time and the average seepage flow rate exceeds 10%, it shall be discarded and the discarded seepage flow rate shall be re-measured in the test. The seepage flow rate at each time shall be Q =S×h ,in h It is the height of water level drop during the measurement period after the flow rate stabilizes; Step 6: After the test of the measuring point is completed, the water supply pump (209) is turned off, the rotating cylinder (200) is pulled out, and the water in the drill hole is sucked out; the device is pushed to the next measuring point target position, and steps 2, 3, 4 and 5 are repeated; Step 7: After the test is completed, calculate the approximate permeability coefficient of the test soil according to the following formula : Q-average seepage flow; t - Record the time of the time period; A - The cross-sectional area of ​​the rotating drum (200) port excluding the water receiving ring; , are the hydrodynamic viscosity coefficients at the water temperature and 20°C during the measuring time, respectively.

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