CN108007840A - A kind of permeability apparatus that can simulate waterpower gradient magnitude and direction dynamic changing condition - Google Patents

Abstract

An osmotic device capable of simulating the dynamic change conditions of hydraulic gradient size and direction, comprising a osmometer main body, a water supply device, and a water collection device. The glass tube is installed on the rotating bracket, and the plexiglass tube adjusts the inclination angle with the rotation of the rotating bracket. The water supply device includes a water storage tank and a water supply bucket. The water storage tank is connected to the water supply bucket through a connecting pipeline, and the water supply bucket is connected to the main body of the osmometer through the connecting pipeline to supply water to the main body of the osmometer. The water collection device includes a water collection bucket, the water collection bucket is connected to the main body of the permeameter through a connecting pipeline, and the water infiltrated by the main body of the permeameter under the condition of changing the size and direction of the hydraulic gradient flows into the water collection bucket. The invention changes the size and direction of the hydraulic gradient of the test sample by adjusting the relative height of the water supply bucket and the water collection bucket and the inclination angle of the plexiglass tube, thereby simulating the real seepage environment of the test sample and dynamically measuring the test sample. the permeability coefficient.

Description

An infiltration device capable of simulating the dynamic change conditions of hydraulic gradient size and direction

technical field

The invention relates to the technical field of geotechnical engineering, in particular to an infiltration device capable of simulating the dynamic change conditions of hydraulic gradient size and direction.

Background technique

The study of soil permeability is an important and practical topic in the field of soil mechanics and geotechnical engineering. It is closely related to human life and involves a wide range of fields, including: water conservancy, construction, mining, transportation, petroleum, agriculture Wait. The phenomenon of water flowing in soil pores is called seepage. Seepage will cause seepage deformation of soil and directly affect the stability and safety of geotechnical structures and foundations. It is extremely important to study the permeability of soil. The permeability coefficient is an index that comprehensively reflects the permeability of the soil. Accurately measuring the permeability coefficient of the soil in the real environment can better judge the permeability of the soil, which is of great significance to the calculation of the permeability.

At present, the methods for indoor determination of permeability coefficient are mainly divided into constant head method and variable head method. The permeability coefficient is measured by changing the seepage velocity to form different hydraulic gradients. These two methods only consider adjusting the size of the hydraulic gradient but ignore the adjustment of the direction of the hydraulic gradient. They cannot simulate the impact of dynamic changes in the size and direction of the hydraulic gradient on the hydraulic coefficient, and cannot accurately reflect the permeability characteristics of soil under different hydraulic gradients in the real environment. In order to simulate the real seepage environment inside the soil and more accurately obtain the dynamic evolution law of the hydraulic gradient (change in size and direction) of the soil permeability coefficient, a set of conditions that can simulate the dynamic change in the size and direction of the hydraulic gradient was developed. The infiltration device for the determination of soil permeability coefficient is very important.

Contents of the invention

In order to solve the problems existing in the prior art, the present invention provides a kind of infiltration device capable of simulating the dynamic change conditions of the hydraulic gradient size and direction. In the test, the dynamic change situation of the hydraulic gradient size and direction inside the soil can be simulated. Under the conditions of single change in gradient size and direction, or simultaneous dynamic changes in hydraulic gradient size and direction, the soil permeability coefficient can be measured to more accurately obtain the dynamic evolution law of soil permeability coefficient under the condition of hydraulic gradient size and direction change, and can also By observing the seepage deformation process of the test sample in the plexiglass tube, the size and direction of the critical hydraulic gradient can be determined, which can more intuitively reflect the seepage characteristics of the soil.

The technical scheme that the present invention takes is:

An osmotic device capable of simulating the dynamic change conditions of hydraulic gradient size and direction, comprising a osmometer main body, a water supply device, and a water collection device. The glass tube is installed on the rotating bracket, and the plexiglass tube adjusts the inclination angle with the rotation of the rotating bracket. The water supply device includes a water storage tank and a water supply bucket. The water storage tank is connected to the water supply bucket through a connecting pipeline, and the water supply bucket is connected to the main body of the osmometer through the connecting pipeline to supply water to the main body of the osmometer. The water collection device includes a water collection bucket, the water collection bucket is connected to the main body of the permeameter through a connecting pipeline, and the water infiltrated by the main body of the permeameter under the condition of changing the size and direction of the hydraulic gradient flows into the water collection bucket.

The main body of the permeameter also includes an upper cover plate, an upper water permeable plate, a lower water permeable plate, a support pipe, a lower cover plate, fastening bolts, and a fixed bracket. One end of the plexiglass tube is placed in the circular groove on the top of the lower cover, and the bottom of the lower cover is provided with a water outlet, which is connected to the outlet pipe. The upper and lower permeable plates are placed in the plexiglass tube, and the lower permeable plate is placed by Supported by the support tube on the top groove of the lower cover plate, the test sample is placed between the upper permeable plate and the lower permeable plate, the upper permeable plate is filled with gravel or glass beads, the other end of the plexiglass tube is provided with an upper cover plate, and the upper cover plate A water inlet is arranged on the top, and the water inlet is connected with the water supply rubber pipe, and the upper cover and the lower cover make the plexiglass tube form a closed space. The plexiglass tube can be divided into a water inlet buffer section, a sample loading section, and a water outlet section from the upper cover plate to the lower cover plate. Three bolt holes are evenly distributed around the circumference of the upper cover plate and the lower cover plate. The support on the rotating bracket The ring is set in the middle of the outside of the plexiglass tube, and the fastening bolts pass through the bolt holes of the upper cover, the bolt holes of the supporting ring and the bolt holes of the lower cover in sequence, and the upper cover, the plexiglass tube, the supporting ring and the lower cover The boards are tightly connected, the supporting ring is fixed on the fastening bolts through nuts, the supporting rod on the rotating bracket is inserted into the slot corresponding to the vertical plate of the fixed bracket, the supporting rod can rotate freely in the slot, and the test The sample plexiglass tube adjusts the inclination angle with the rotation of the support rod on the rotating bracket.

The side wall of the water supply barrel of the water supply device is installed with a water inlet rubber pipe and an overflow water rubber pipe from top to bottom, and the water inlet rubber pipe is connected with the water storage tank, and the pure water in the water storage tank is pumped by the water pump installed on the water inlet rubber pipe. Water or distilled water is delivered to the water supply bucket, and the overflow rubber tube returns the overflowing water from the water supply bucket to the water storage tank. The water supply rubber tube is installed at the bottom of the water supply bucket to connect with the water inlet of the upper cover, and the water supply rubber tube is used to supply water to the main body of the permeation instrument.

The bottom of the water collection bucket of the water collection device is provided with a water outlet rubber tube, which is connected to the water outlet hole of the lower cover plate, and the water permeated by the main body of the permeameter under the condition of hydraulic gradient and direction changes flows into the water collection bucket through the water outlet rubber tube , Install a drainage rubber tube on the side wall of the water collection bucket to collect the overflowing water into the graduated cylinder.

The upper cover plate is a plexiglass disc, and a water inlet hole is set at the center of the top surface of the disc. The water inlet hole is connected with the water supply rubber pipe and sealed by a throat hoop. A sealing ring is provided on the contact surface between the groove and the plexiglass tube; the lower cover plate is a plexiglass disc, and a water outlet hole is set at the center of the bottom surface of the disc, and the water outlet hole is connected with the water outlet rubber tube and sealed by a throat hoop; the lower cover plate A circular groove is arranged on the top surface, and a sealing ring is arranged on the contact surface between the circular groove and the plexiglass tube.

The plexiglass tube is a transparent material, the diameter is greater than or equal to 5 times the particle size d85 of the test sample, _and its length is 3 to 4 times the diameter. The support tube is a transparent plexiglass tube, the height of which is 1 to 1.5 times the diameter, and the tube wall is evenly distributed with permeable holes.

Both the upper permeable plate and the lower permeable plate are plexiglass discs covered with uniform permeable holes, and plasticine is applied along the edge of the permeable plate on the side where the permeable plate is in contact with the test sample.

The rotating bracket includes a support ring and two support rods; the support ring is provided with three evenly distributed bolt holes, which are made of steel plates, and the support rod is a gear whose outer surface is evenly distributed with tooth grooves and the direction of the tooth grooves is consistent with the direction of the rod axis The rod is made of steel rods. The support ring passes through the fastening bolt and is placed in the middle of the plexiglass tube, and is fixed on the fastening bolt by a nut. The plane of the ring is perpendicular to the axis of the plexiglass tube; the two support rods are axisymmetric Arranged on both sides of the ring and welded on the edge of the ring, the support rod is placed on the slot corresponding to the fixed bracket, the support rod can rotate freely in the slot, and the plexiglass tube adjusts the inclination angle with the rotation of the support rod. In order to change the direction of the hydraulic gradient, a bayonet is provided above the slot, and the card in the bayonet is stuck on the tooth groove of the support rod to limit the rotation of the support rod.

The fixed bracket includes two vertical plates placed in parallel and two fixing bolts. The two vertical plates are made of steel plates. Two bolt holes are symmetrically arranged on the bottom of one vertical plate with the vertical axis, and the other vertical plate is at the corresponding position. Set bolt holes, the fixing bolts pass through the bolt holes corresponding to the two vertical plates, the bolts are fixed to the vertical plates by nuts, and the corresponding card slots are set at a certain distance from the top of the vertical plates along the vertical axis of the vertical plates, directly above the card slots A bayonet slot is provided, and a card made of steel plate is installed on the bayonet slot, and the card can be stuck on the tooth groove of the support rod.

Both the water supply bucket and the water collection bucket are provided with pulling parts, and the relative heights of the water supply bucket and the water collection bucket are adjusted by the lifting parts to change the water head pressure on both sides of the test sample.

The present invention is an infiltration device capable of simulating the dynamic change conditions of the size and direction of the hydraulic gradient. By adjusting the relative height of the water supply bucket and the water collection bucket and the inclination angle of the plexiglass tube, the size and direction of the hydraulic gradient of the test sample are changed, thereby simulating Test the real seepage environment where the sample is located, dynamically measure the permeability coefficient of the test sample, and more accurately obtain the dynamic evolution law of the permeability coefficient of the soil under the condition of hydraulic gradient size and direction change; use a transparent plexiglass tube to test It is convenient to observe the beating and movement of fine particles, the generation of permeation channels, the degree of turbidity of water and other phenomena during the experiment, more accurately determine the size and direction of the critical hydraulic gradient, and can directly reflect the permeability characteristics of the soil.

Description of drawings

Figure 1 is a schematic diagram of the overall structure of the present invention.

Fig. 2 is a schematic diagram of the overall front view structure of the present invention.

Fig. 3 is a schematic diagram of the front view of the main body of the permeameter of the present invention.

Fig. 4 is a schematic diagram of the left view of the main body of the permeameter according to the present invention.

Fig. 5 is a schematic diagram of the left view structure of the permeameter body of the present invention at an inclination angle.

Fig. 6 is a schematic diagram of the front structure of the upper cover plate of the present invention.

Fig. 7 is a schematic bottom view of the lower cover plate of the present invention.

Fig. 8 is a schematic structural view of the water-permeable panel of the present invention.

Fig. 9 is a schematic diagram of the front structure of the support tube of the present invention.

Fig. 10 is a schematic top view of the rotating bracket of the present invention.

Fig. 11 is a front structural schematic view of the fixing bracket of the present invention.

FIG. 12 is an enlarged view of A in FIG. 11 .

Fig. 13 is a left view structural diagram of the fixing bracket of the present invention.

FIG. 14 is an enlarged view of B in FIG. 13 .

Detailed ways

As shown in FIG. 1 , an osmosis device capable of simulating dynamic changes in the magnitude and direction of a hydraulic gradient, the osmosis device includes a osmometer body 1 , a water supply device 2 , and a water collection device 3 . Referring to Fig. 3, the main body 1 of the permeameter includes an upper cover plate 4, a plexiglass tube 8, an upper permeable plate 6, a lower permeable plate 7, a support tube 9, a lower cover plate 5, fastening bolts 10, and a rotating bracket 11 , fixed bracket 12. One end of the plexiglass tube 8 is placed in the circular groove at the top of the lower cover plate 5 , the bottom surface of the lower cover plate 5 is provided with a water outlet, and the water outlet is connected to the water outlet pipe 19 , and the upper permeable plate 6 and the lower permeable plate 7 are placed in the plexiglass tube 8 , the lower permeable plate 7 is supported by the support tube 9 placed on the top groove of the lower cover plate 5, the test sample 14 is placed between the upper permeable plate 6 and the lower permeable plate 7, and the upper permeable plate 6 is filled with gravel or glass beads 13 , the other end of the plexiglass tube 8 is provided with an upper cover 4, the top of the upper cover 4 is provided with a water inlet, the water inlet is connected with the water supply rubber tube 18, the upper cover 4 and the lower cover 5 make the plexiglass tube 8 form a closed space , the plexiglass tube 8 can be divided into a water inlet buffer section 15, a sample loading section 16, and a water outlet section 17 from the upper cover plate 4 to the lower cover plate 5, and three are evenly distributed around the circumference of the upper cover plate 4 and the lower cover plate 5. Bolt hole. The support ring 29 on the swivel bracket 11 is set in the middle position outside the plexiglass tube 8, and the fastening bolts 10 pass through the 4 bolt holes of the upper cover, the 29 bolt holes of the support ring and the 5 bolt holes of the lower cover successively, and the upper cover Plate 4, plexiglass tube 8, support ring 29 and lower cover plate 5 are tightly connected, support ring 29 is fixed on the fastening bolt 10 by nuts, and the support rod 30 on the rotating bracket 11 is inserted into the fixed bracket 12 vertical plate 31 corresponding to the slot 33, the support rod 30 can rotate freely in the slot 33, and the plexiglass tube 8 containing the test sample adjusts the inclination angle with the rotation of the support rod 30 on the rotating bracket 11, thereby realizing the hydraulic gradient. The change of direction, when the main body of the permeameter is adjusted to the required hydraulic gradient direction, the card 35 on the bayonet 34 is stuck on the tooth groove of the support rod 30 to limit the rotation of the support rod 30, so as to realize the fixation of the inclined plexiglass tube, Prevent the rotation of the plexiglass tube from causing errors to the experimental results.

Referring to FIG. 1 , the water supply device 2 includes a water storage tank 20 , a water pump 23 , a water supply barrel 21 , and connecting pipelines. The water supply barrel 21 side wall is installed with water inlet rubber pipe 24 and overflow water rubber pipe 25 from top to bottom, water inlet rubber pipe 24 is connected with water storage tank 20, is filled in the water storage tank 20 by the water pump 23 that is installed on the water inlet rubber pipe 24. The pure water or distilled water put is transported in the water supply bucket 21, and the water overflowed by the water supply bucket 21 is returned to the water storage tank 20 by the overflow rubber tube 25, so as to ensure that the water supply bucket 21 provides a constant water head and reaches the effect of circulating water. A water supply rubber tube 18 is arranged at the bottom of the water supply bucket 21 to connect with the water inlet hole of the upper cover plate 4, and water is supplied to the main body 1 of the permeation meter through the water supply rubber tube 18.

The water collecting device 3 includes: a water collecting bucket 22, a measuring cylinder 27, and connecting pipelines. The water outlet rubber tube 19 is arranged at the bottom of the water collection bucket 22 to connect with the water outlet hole of the lower cover plate 5, and the water infiltrated by the main body of the permeameter 1 flows into the water collection bucket 22 through the water outlet rubber tube 19 under the condition of the hydraulic gradient size and direction change, and the water collection bucket 22 The side wall is equipped with a drainage rubber tube 26 to collect the overflowing water in the measuring cylinder 27, to ensure that the water collecting bucket 22 provides a constant water head, and to facilitate the collection of the oozing liquid.

Referring to Fig. 6, the upper cover plate 4 is a plexiglass disc, and a water inlet hole is arranged at the center of the top surface of the disc. The water inlet hole is connected with the water supply rubber pipe 18 and sealed by a throat hoop. The groove has a depth of 15 mm to 25 mm, and a sealing ring 36 is provided on the contact surface between the groove and the plexiglass tube 8 . Referring to Fig. 7, the lower cover plate 5 is a plexiglass disc, and a water outlet hole is arranged at the center of the bottom surface of the disc, the water outlet hole is connected with the water outlet rubber tube 19 and sealed by a throat hoop, and a circular groove is arranged on the top surface of the lower cover plate , the depth is 15mm~25mm, and a sealing ring 36' is provided on the contact surface between the groove and the plexiglass tube 8.

Referring to Fig. 3, the plexiglass tube 8 is a transparent material, which is convenient for observing relevant phenomena during the experiment, and its diameter is not less than 5 times of _the test sample particle size d85 , and its length is 3 to 4 times of the diameter.

Referring to Fig. 8, the upper permeable plate 6 and the lower permeable plate 7 are plexiglass disks covered with uniform permeable holes, and plasticine is applied along the edge of the permeable plate on the side where the permeable plate is in contact with the test sample 14 to prevent the test Sample 14 flows out from the gap between the permeable plate and the pipe wall.

As shown in Fig. 9, the support tube 9 is a transparent plexiglass tube with a diameter of 100 mm to 150 mm and a height of 1 to 1.5 times the diameter. The tube wall is evenly distributed with permeable holes, which is convenient for observing the water flow in the outlet section.

Referring to FIG. 10 , the rotating bracket 11 includes a support ring 29 and two support rods 30 . The support ring 29 is provided with three evenly distributed bolt holes, which are made of steel plates. The support rod 30 is a gear rod whose outer surface is evenly distributed with tooth grooves and the direction of the tooth grooves is consistent with the direction of the rod axis, and is made of steel rods. The support ring 29 passes through the fastening bolt 10 and is set in the middle of the plexiglass tube 8, and is fixed on the fastening bolt 10 by a nut. The plane of the ring is perpendicular to the axis of the plexiglass tube 8; The both sides of the ring 29 are welded on the edge of the ring 29, the support rod 30 is placed on the corresponding draw-in groove 33 of the fixed bracket 12, the support rod 30 can rotate freely in the draw-in groove 33, and the plexiglass tube 8 follows the support rod 30 Rotate to adjust the angle of inclination, thereby realizing the change of the direction of the hydraulic gradient. A bayonet 34 is provided above the draw-in groove 33, and the card 35 in the bayonet 34 is stuck on the tooth groove of the support rod 30 to limit the rotation of the support rod 30, so as to realize the The fixation of the inclined plexiglass tube prevents the rotation of the plexiglass tube from causing errors to the experimental results.

Referring to FIGS. 11-14 , the fixing bracket 12 includes two parallel vertical plates 31 and two fixing bolts 32 . The two vertical plates 31 are made of steel plates, and two bolt holes are arranged symmetrically with the vertical axis at the bottom of one vertical plate, and the other vertical plate is provided with bolt holes at corresponding positions, and the fixing bolts 32 pass through the corresponding bolt holes of the two vertical plates , the bolt 32 is fixed to the vertical plate 31 by nuts, a corresponding card slot 33 is set at a certain distance from the top of the vertical plate along the vertical axis of the vertical plate, a bayonet 34 is provided directly above the card slot, and a steel plate is installed on the bayonet 34 The card 35 is made, and the card 35 can be stuck on the supporting rod 30 tooth grooves.

The rubber tube adopts a high-strength rubber tube, and water-leakage measures are taken at the connection between the rubber tube and the components. Both the water supply bucket 21 and the water collection bucket 22 are provided with lifting parts 28, and the relative heights of the water supply bucket 21 and the water collection bucket 22 are adjusted by the lifting parts 28 to change the water head pressure on both sides of the test sample.

The following describes in detail the method of using the present invention to measure soil permeability coefficient under the condition of hydraulic gradient size and direction dynamic change:

(1) Sample loading: place one end of the plexiglass tube 8 in the top groove of the lower cover 5 placed horizontally, the support tube 9 is placed in the center of the top groove of the lower cover 5, and the lower permeable plate 7 is placed in the support tube 9, smear plasticine on the gap between the lower permeable plate 7 and the wall of the plexiglass tube 8; Then calculate the required weight of the sample according to the controlled dry bulk density and sample height. After weighing the ingredients, in order to reduce the separation of coarse and fine materials and ensure the uniformity of the sample, you can add an amount equivalent to that of the test sample. The sample weight is 1~2% moisture, mix evenly and layer into the plexiglass tube 8, and use the method of compaction or vibration encryption to reach the required density; Fill gravel or glass bead 13 above 6, and gravel or glass bead reach the effect of water buffering, uniform infiltration, the supporting ring 29 on the rotating support 11 is enclosed within the outside of plexiglass tube 8, cover upper cover plate 4, tighten The fastening bolts 10 pass through the 4 bolt holes of the upper cover, the 29 bolt holes of the supporting ring, and the 5 bolt holes of the lower cover in turn, and the upper cover 4, the plexiglass tube 8, the rotating bracket 11, and the lower cover 5 are tightly connected. A good instrument is placed on the fixed support 12 and connected to the water supply device 2 .

(2) Saturation: measure the actual thickness of the sample, use the hot water saturation method to perform saturated exhaust, put the water inlet of the plexiglass tube 8 holding the test sample 14 down, store hot water in the water storage tank 20, and pass it through the water pump 23. Send hot water to the water supply bucket 21, so that the water level of the water supply bucket 21 is slightly higher than the bottom surface of the sample, slowly lift the water supply bucket 21, 1 cm each time, wait until the water level of the water supply bucket is equal to the water level in the sample, and then continue to lift. Water infiltrates slowly upwards from the bottom of the apparatus, making sure to slowly saturate the sample to completely remove the air from the sample.

(3) After the sample is saturated, connect the water collection device 3, and adjust the relative height of the water supply bucket 21 and the water collection bucket 22 to make the water level consistent, slowly adjust the inclination angle of the plexiglass tube 8, and when the angle required by the experiment is reached, the card 35 is stuck in the Put the support rod 30 in the tooth groove, then adjust the relative height of the water supply bucket 21 and the water collection bucket 22 to reach the initial seepage gradient, and then increase the seepage gradient step by step after stabilization, and measure the water seepage with the measuring cylinder 21 after each time the water head is raised for 30 minutes to 1 hour The time interval between each measurement and reading is 10 to 20 minutes, and the water temperature and room temperature are measured at the same time, and the changes of the test samples in the sample loading section are observed through the transparent plexiglass tube. For example, the beating, movement, and generation of permeation channels of fine particles, observe the degree of turbidity of the water in the outlet section, whether the fine particles are carried out by the water flow, etc. If the seepage measured three times is basically stable and there is no abnormal phenomenon, it can be upgraded to Next level hydraulic gradient. Repeat the above operations for each level of hydraulic gradient until the test sample is damaged and the water head can no longer increase, the test can be ended. The size and direction of the hydraulic gradient when the test sample is infiltrated and damaged is the critical hydraulic gradient size and direction. Measure the permeability coefficient of the test sample under each level of hydraulic gradient, and obtain the dynamic evolution law of the permeability coefficient of the soil under the condition of hydraulic gradient size and direction change.

Claims (10)

1. An infiltration device capable of simulating the dynamic change conditions of hydraulic gradient size and direction, comprising an infiltration meter main body (1), a water supply device (2), and a water collection device (3), characterized in that: the infiltration meter main body (1 ) includes a rotating bracket (11), a plexiglass tube (8) containing a test sample (14), the plexiglass tube (8) is installed on the rotating bracket (11), and the plexiglass tube (8) is The rotating bracket (11) rotates to adjust the inclination angle; the water supply device (2) includes a water storage tank (20) and a water supply bucket (21). 21) Connect the main body (1) of the permeameter through the connecting pipeline, and supply water to the main body (1) of the permeameter; the water collecting device (3) includes a water collecting bucket (22), and the water collecting bucket (22) is connected to the permeameter through the connecting pipeline The main body (1), the water infiltrated by the main body (1) of the infiltration meter (1) flows into the water collection bucket (22) under the condition of changing the size and direction of the hydraulic gradient. 2. According to claim 1, an osmotic device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the main body (1) of the permeameter also includes an upper cover plate (4), an upper permeable plate (6 ), the lower permeable plate (7), the support pipe (9), the lower cover plate (5), the fastening bolt (10), the fixing bracket (12); One end of the plexiglass tube (8) is placed in the circular groove on the top of the lower cover (5), and the bottom of the lower cover (5) is provided with a water outlet, which is connected to the water outlet rubber tube (19), and the upper permeable plate (6 ) and the lower permeable plate (7) are placed in the plexiglass tube (8), the lower permeable plate (7) is supported by the support tube (9) placed on the top groove of the lower cover plate (5), and the test sample (14) Placed between the upper permeable plate (6) and the lower permeable plate (7), the upper permeable plate (6) is filled with gravel or glass beads (13), and the other end of the plexiglass tube (8) is provided with an upper cover plate (4), A water inlet is provided on the top of the upper cover (4), and the water inlet is connected to the water supply rubber tube (18). The upper cover (4) and the lower cover (5) make the plexiglass tube (8) form a closed space; The plexiglass tube (8) can be divided into a water inlet buffer section (15), a sample loading section (16), and a water outlet section (17) from the upper cover plate (4) to the lower cover plate (5). (4) Three bolt holes are evenly distributed on the circumference of the lower cover plate (5), and the support ring (29) on the rotating bracket (11) is set in the middle position outside the plexiglass tube (8), fasten the bolts (10 ) through the bolt holes of the upper cover (4), the bolt holes of the supporting ring (29) and the bolt holes of the lower cover (5) in sequence, and put the upper cover (4), the plexiglass tube (8), the supporting ring ( 29) is closely connected with the lower cover plate (5), the supporting ring (29) is fixed on the fastening bolt (10) by a nut, and the supporting rod (30) on the rotating bracket (11) is inserted into the fixing bracket (12) In the slot (33) corresponding to the vertical plate (31), the support rod (30) can rotate freely in the slot (33). 11) Adjust the angle of inclination by turning the support rod (30) on the top. 3. According to claim 1, an osmosis device capable of simulating the dynamic change conditions of hydraulic gradient size and direction, characterized in that: the side wall of the water supply bucket (21) of the water supply device (2) is installed from top to bottom for water intake The rubber tube (24) and the overflow rubber tube (25), the water inlet rubber tube (24) is connected with the water storage tank (20), and the water storage tank (20) is pumped by the water pump (23) installed on the water inlet rubber tube (24) The pure water or distilled water contained in the tank is delivered to the water supply barrel (21), and the overflow rubber tube (25) returns the overflowed water from the water supply barrel (21) to the water storage tank (20), and the water supply rubber tube is set at the bottom of the water supply barrel (21) (18) Connect with the water inlet of the upper cover (4), and supply water to the main body (1) of the permeation meter through the water supply rubber tube (18). 4. According to claim 1, an osmosis device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the bottom of the water collection bucket (22) of the water collection device (3) is provided with a water outlet rubber tube (19) , the water outlet rubber tube (19) is connected to the water outlet hole of the lower cover (5), and the water infiltrated by the main body of the permeameter (1) flows into the water collection bucket (22) through the water outlet rubber tube (19) under the condition of changing the size and direction of the hydraulic gradient ), a drainage rubber tube (26) is installed on the side wall of the water collecting bucket (22) to collect the overflowing water into the measuring cylinder (27). 5. According to claim 2, an osmotic device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the upper cover plate (4) is a plexiglass disc, which is set at the center of the top surface of the disc Water inlet, the water inlet is connected with the water supply rubber pipe (18) and sealed by a hose clamp, the bottom surface of the upper cover plate (4) is provided with a circular groove, and the contact surface between the circular groove and the plexiglass pipe (8) is provided with Sealing ring (36); the lower cover plate (5) is a plexiglass disc, and a water outlet hole is set at the center of the bottom surface of the disc, the water outlet hole is connected with the water outlet rubber tube (19) and sealed by a throat hoop, the lower cover plate ( 5) A circular groove is provided on the top surface, and a sealing ring (36) is provided on the contact surface between the circular groove and the plexiglass tube (8). 6. According to claim 1, a osmosis device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the plexiglass tube (8) is a transparent material with a diameter greater than or equal to the test sample particle size d ₈₅ 5 times of the diameter, and its length is 3 to 4 times of the diameter; the support tube (9) is a transparent plexiglass tube, the height of which is 1 to 1.5 times of the diameter, and the pipe wall is evenly distributed with permeable holes. 7. According to claim 2, an infiltration device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the upper permeable plate (6) and the lower permeable plate (7) are covered with uniform permeable holes Smear plasticine on the side of the permeable plate in contact with the test sample (14) along the edge of the permeable plate. 8. An osmosis device capable of simulating dynamic changes in hydraulic gradient size and direction according to claim 2, characterized in that: the rotating support (11) includes a supporting ring (29) and two supporting rods (30) The support ring (29) is provided with three evenly distributed bolt holes, which are made of steel plates, and the support rod (30) is a gear rod whose outer surface is evenly distributed with tooth grooves and the direction of the tooth grooves is consistent with the direction of the rod axis, and is made of steel rods. The support ring (29) passes through the fastening bolt (10) and is set in the middle of the plexiglass tube (8), and is fixed on the fastening bolt (10) by a nut. The plane of the ring and the axis of the plexiglass tube (8) vertical; two support rods (30) are arranged axisymmetrically on both sides of the ring (29) and welded on the edge of the ring (29), and the support rods (30) are placed in the corresponding slots (33 ), the support rod (30) can rotate freely in the slot (33), and the plexiglass tube (8) adjusts the inclination angle with the rotation of the support rod (30), thereby realizing the change of the direction of the hydraulic gradient. In the slot ( 33) A bayonet (34) is provided on the top, and the card (35) in the bayonet (34) is stuck on the tooth groove of the support rod (30) to limit the rotation of the support rod (30). 9. According to claim 2, an infiltration device capable of simulating dynamic changes in hydraulic gradient size and direction, characterized in that: the fixed support (12) includes two vertical plates (31) placed in parallel and two fixed Bolts (32), two vertical plates (31) are made of steel plates, two bolt holes are arranged symmetrically with the vertical axis at the bottom of one vertical plate, bolt holes are set at the corresponding positions on the other vertical plate, and the fixing bolts (32) penetrate Through the bolt holes corresponding to the two vertical plates, the bolts (32) and the vertical plate (31) are fixed by nuts, and the corresponding card slots (33) are set at a certain distance from the top of the vertical plate (31) along the vertical axis of the vertical plate, A bayonet (34) is provided directly above the draw-in groove (33), and a card (35) made of a steel plate is installed on the bayonet (34), and the card (35) can be stuck on the support rod (30) tooth groove. 10. An osmosis device capable of simulating the dynamic change conditions of hydraulic gradient size and direction according to claim 1, characterized in that: the water supply bucket (21) and the water collection bucket (22) are both provided with lifting parts (28) , by pulling the component (28) to adjust the relative height of the water supply bucket (21) and the water collection bucket (22), to change the water head pressure on both sides of the test sample (14).