Experimental device for studying loess slope water flow scouring erosion

Abstract

The utility model discloses an experimental device for studying loess slope water flow scouring erosion. The experimental device comprises a support, a water tank, a flow slowing groove, a simulation slope groove and a collecting device. The water tank is arranged on the support, the flow slowing groove is arranged between the water tank and the simulation slope groove, and the collecting device is located below the end, away from the flow slowing groove, of the simulation slope groove. The water tank comprises a water tank wall face, a door opening is formed in the side, close to the slow flow groove, of the water tank wall face, and a door plate is movably installed on the door opening. A first baffle and a second baffle are arranged in the water tank in parallel at intervals, and a drain hole for water flow to pass through is formed in the plate surface of the second baffle; a first opening and a second opening are formed in a bottom plate of the water tank; an inclination angle adjusting device is installed on the lower portion of the simulation slope groove. According to the utility model, the liquid level in the water tank is constant, the erosion condition under the action of constant flow and variable flow can be simulated, the high precision of the erosion flow is ensured, and the test duration is optimized.

Description

Technical Field

[0001] The utility model belongs to the technical field of geotechnical engineering, and in particular relates to an experimental device for studying water flow scouring and erosion of loess slopes. Background Art

[0002] With the rapid development of social economy, various engineering construction activities are increasing day by day. Irrational engineering construction such as excavation of slope foot and filling on slope, as well as unreasonable agricultural activities such as overcultivation and farmland irrigation, have seriously damaged the geological environment of the loess region, causing serious soil and water loss in the loess region. Secondly, loess slopes are often subjected to short-duration erosive rainstorms, and the runoff generated is the main source of erosion affecting slope engineering soil erosion. Therefore, it is necessary to continue to deepen the study of the development mechanism of rill erosion on loess slopes. Among them, studying morphological changes is a prerequisite for understanding the mechanism of rill occurrence. Quantitative research on the morphology and erosion quality of slope rills during the rill occurrence process is of great significance for analyzing the rill erosion mechanism of loess slopes. Because the rill hydrodynamic test can better simulate the influence of different runoff intensity changes and temporal and spatial evolution differences during the rill development process, it is very necessary to carry out this test for theoretical guidance of engineering practice.

[0003] However, most of the current studies on the development mechanism of rills on loess slopes only consider the erosion under conditions such as constant flow, single time and single slope angle, and it is still difficult to accurately define the morphological characteristics of rills. Utility Model Content

[0004] The purpose of the utility model is to provide an experimental device for studying water scouring and erosion of loess slopes. The device comprises a bracket, a water tank, a slow-flow trough, a simulated slope trough and a collecting device, so as to simulate and measure the scouring and erosion of variable-flow water flow on the loess slope. The device has the characteristics of intuitively observing the erosion situation and high precision in erosion flow control.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: an experimental device for studying water scouring and erosion of loess slopes, characterized in that it includes a bracket, a water tank, a slow flow trough, a simulated slope trough and a collecting device; the water tank is arranged on the bracket, the slow flow trough is detachably arranged between the water tank and the simulated slope trough, and the collecting device is located below the end of the simulated slope trough away from the slow flow trough;

[0006] A door opening is provided on one side of the water tank close to the slow flow groove, and a door panel is movably installed on the door opening;

[0007] A first baffle and a second baffle are arranged in parallel and at intervals in the water tank, and a drainage hole for water flow to pass through is opened on the surface of the second baffle, and the number of the drainage holes is multiple;

[0008] The bottom plate of the water tank is provided with a first opening and a second opening, the first opening is located between the first baffle plate and the wall of the water tank, and the second opening is located between the first baffle plate and the second baffle plate;

[0009] The lower part of the simulated slope groove is provided with an inclination angle adjustment device for adjusting the inclination angle of the simulated slope groove;

[0010] The simulated slope trough comprises an inner trough surface capable of accommodating a fine sand layer and a sample layer.

[0011] The above-mentioned experimental device for studying water scouring and erosion of loess slopes is characterized in that the slow flow trough is overlapped between the simulated slope trough and the water tank.

[0012] The above-mentioned experimental device for studying water scouring and erosion of loess slopes is characterized in that the first baffle and the second baffle are both vertically arranged in the water tank, and the top of the first baffle is an inclined surface.

[0013] The above-mentioned experimental device for studying water scour and erosion of loess slopes is characterized in that the height difference between the first baffle and the wall of the water tank is 2 to 4 cm.

[0014] The above-mentioned experimental device for studying water scouring and erosion of loess slopes is characterized in that the lower part of the first opening is connected to an overflow pipe, the lower part of the second opening is connected to a water inlet pipe, and a valve is installed on the water inlet pipe.

[0015] The above-mentioned experimental device for studying water scouring and erosion of loess slopes is characterized in that the inclination angle adjustment device includes a telescopic rod and a slide groove installed at the bottom of the simulated slope trough, the telescopic rod can be slidably installed on the slide groove, and the slide groove is located at one end of the simulated slope trough close to the slow flow trough.

[0016] The above-mentioned experimental device for studying water scour and erosion of loess slopes is characterized in that the material of the simulated slope trough is transparent organic glass, and the simulated slope trough is engraved with scales.

[0017] The above-mentioned experimental device for studying water scouring and erosion of loess slopes is characterized in that a water outlet is detachably provided at the end of the simulated slope trough close to the collecting device.

[0018] The above-mentioned experimental device for studying the scouring and erosion of loess slopes by water flow is characterized in that the water outlet is protrudingly arranged at the end of the simulated slope trough, and the shape of the water outlet is a prism-shaped body. The prism-shaped water outlet includes a connected top plane part and a bottom plane part, the top plane part and the bottom plane part are parallel, the area of ​​the top plane part is less than the area of ​​the bottom plane part, the top plane part is installed at the end of the simulated slope trough, and the bottom plane part is facing the collecting device.

[0019] The above-mentioned experimental device for studying water scour and erosion of loess slopes is characterized in that the bracket includes a plate for placing a water tank and a support member located under the plate to support the plate.

[0020] Compared with the prior art, the utility model has the following advantages:

[0021] 1. The utility model discloses an experimental device for studying water scouring and erosion of loess slope, comprising a slow flow trough, a simulated slope trough, a collecting device and a water tank of fixed height, a first baffle and a second baffle arranged in the water tank body, a first opening and a second opening opened on the bottom plate of the water tank, and an overflow pipe connected to the first opening and a water inlet pipe connected to the second opening. Through the cooperation between the above components, the liquid level in the water tank is kept constant, and the erosion conditions under the action of constant flow and variable flow are simulated, thereby ensuring the high precision of the erosion flow and optimizing the test duration.

[0022] 2. In the experimental device for studying water scouring and erosion of loess slopes of the utility model, the first baffle includes an inclined surface at the top, which can make the water overflowing the first baffle fall vertically along the surface of the first baffle to avoid liquid splashing.

[0023] 3. The experimental device for studying water scouring and erosion of loess slopes of the utility model comprises a door panel installed on a door opening and a scale engraved on the door opening. The clearance between the door panel and the bottom plate of a water tank can be adjusted by raising the height of the door panel, thereby adjusting and controlling the amount of eroded water, ensuring that the water flow at the outlet section is equivalent to the width of the slope, avoiding concentrated flow, and better realizing the simulation of slope scouring.

[0024] 4. The experimental device for studying water scouring and erosion of loess slopes of the utility model has a simulated slope trough made of high-strength organic glass and marked with scales, which is convenient for controlling the compaction degree during the experimental sample preparation process. At the same time, the erosion conditions on both sides of the slope during the experiment can be visually observed through the side of the simulated slope trough.

[0025] 5. The experimental device for studying water scouring and erosion of loess slopes of the utility model has reliable principles and high promotion and application value. The data obtained by using the device has guiding significance for theoretical analysis under different working conditions and important reference value for engineering practice. It provides a new reference basis for future research on the mechanism of gully development of loess slope erosion, and provides technical support for the development of different loess gullies and risk assessment of existing earthwork projects.

[0026] The technical solution of the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the utility model.

[0028] Figure 2 Schematic diagram of the structure of the first baffle and the inclined plane.

[0029] Figure 3 for Figure 2 Side view of.

[0030] Description of reference numerals:

[0031] 1—water tank; 3—slow flow trough; 4—simulated slope trough;

[0032] 5—collection device; 6—plate;

[0033] 61—support rod; 62—cross bar;

[0034] 13—first baffle; 14—inclined surface; 15—second baffle;

[0035] 16—drain hole; 17—first opening; 18—water tank wall;

[0036] 19—overflow pipe; 20—second opening; 21—water inlet pipe;

[0037] 22—valve; 23—door plate; 24—scale;

[0038] 25—inclination angle adjustment device; 28—fine sand layer; 29—sample layer;

[0039] 30—Water outlet. DETAILED DESCRIPTION

[0040] like Figures 1 to 3 As shown, this embodiment provides an experimental device for studying water scouring and erosion of loess slopes, comprising a bracket, a water tank 1, a slow flow trough 3, a simulated slope trough 4 and a collecting device 5; the water tank 1 is arranged on the bracket, the slow flow trough 3 is detachably arranged between the water tank 1 and the simulated slope trough 4, and the collecting device 5 is located below the end of the simulated slope trough 4 away from the slow flow trough 3; the slow flow trough 3 is overlapped between the simulated slope trough 4 and the water tank 1; the inner trough surface of the slow flow trough 3 and the inner trough surface of the simulated slope trough 4 are on the same plane; the slow flow trough 3 is provided with a lap plate that can be detachably overlapped on the water tank 1;

[0041] A door opening is provided on one side of the water tank 1 near the slow flow groove 3, and a door panel 23 is movably mounted on the door opening; the door panel 23 can slide up and down to adjust the height of the communication channel between the water tank body and the slow flow groove 3; a scale 24 showing the rising height of the door panel 23 is provided on the side of the door opening;

[0042] The water tank 1 is provided with a first baffle 13 and a second baffle 15 in parallel and at intervals, and a drainage hole 16 is provided on the surface of the second baffle 15 for water to flow through, and the number of the drainage holes 16 is multiple; the first baffle 13 and the second baffle 15 are both vertically arranged in the water tank 1, and the top of the first baffle 13 is a slope 14, and the edge height of the slope 14 close to the second baffle 15 is higher than the edge height of the slope 14 close to the water tank wall, and the angle of the slope is 45°, and the second baffle 15 is located between the first baffle 13 and the slow flow groove 3;

[0043] The bottom plate of the water tank 1 is provided with a first opening 17 and a second opening 20, wherein the first opening 17 is located between the first baffle 13 and the wall of the water tank 1, and the second opening 20 is located between the first baffle 13 and the second baffle 15; specifically, the first opening 17 is located between the wall 18 of the water tank 1 away from the slow flow groove 3 and the first baffle 13;

[0044] The height difference between the first baffle plate 13 and the water tank wall is 2 to 4 cm; the height of the first baffle plate 13 is the height from the highest point of the inclined surface 14 of the first baffle plate 13 to the bottom plate of the water tank;

[0045] The first opening 17 is connected to an overflow pipe 19 at the bottom, the second opening 20 is connected to a water inlet pipe 21 at the bottom, and a valve 22 is installed on the water inlet pipe 21;

[0046] The lower part of the simulated slope groove 4 is provided with an inclination angle adjustment device for adjusting the inclination angle of the simulated slope groove 4;

[0047] The tilt angle adjustment device comprises a telescopic rod 25 and a slide groove installed at the bottom of the simulated slope groove 4, the telescopic rod 25 can be slidably installed on the slide groove, and the slide groove is located at one end of the simulated slope groove 4 close to the slow flow groove 3; the principle of the tilt angle adjustment device for adjusting the tilt angle of the simulated slope groove 4 is as follows: the center line of the slide groove is parallel to the center line of the simulated slope groove 4; the end of the telescopic rod 25 away from the slide groove is vertically fixed to the ground, the telescopic rod 25 can slide along the slide groove, and the height of the telescopic rod 25 is adjustable, and the telescopic rod 25 can be adjusted by sliding the telescopic rod 25 to the slide groove pre-set. The position is set, and the height of the telescopic rod 25 is adjusted to adjust the height of the simulated slope trough 4 close to the slow flow trough 3 from the ground, and the height of the other end of the simulated slope trough 4 from the ground is determined. For example, a cushion block can be placed or one end of the simulated slope trough 4 close to the collection device 5 can be directly placed on the ground to determine the height from the ground. When the cushion block is placed, the height of the cushion block matches the height of the collection device 5. When it is placed directly on the ground, a pit can be dug on the ground to accommodate the collection device 5 to achieve the simulated slope trough 4 to a preset inclination angle.

[0048] The inclination angle is the angle formed between the body of the simulated slope trough 4 or the extension of the body and the ground;

[0049] The simulated slope groove 4 includes an inner groove surface that can accommodate a fine sand layer 28 and a sample layer 29, and the fine sand layer 28 is located between the inner groove surface of the simulated slope groove 4 and the sample layer 29; the simulated slope groove 4 is made of transparent organic glass, and a scale is engraved on the simulated slope groove 4; the height of the fine sand layer 28 and the sample layer 29 can be observed through the scale, so as to achieve a preset compaction degree;

[0050] The end of the simulated slope groove 4 near the collecting device 5 is detachably provided with a water outlet 30; the collecting device 5 may be a water bucket; the water outlet 30 is protrudingly provided at the end of the simulated slope groove 4, and may be in the shape of a prism-shaped body, the prism-shaped water outlet 30 includes a connected top plane portion and a bottom plane portion, the top plane portion and the bottom plane portion are parallel and have different areas, the area of ​​the top plane portion is less than the area of ​​the bottom plane portion, the top plane portion is installed at the end of the simulated slope groove 4, and the bottom plane portion is directly opposite to the collecting device 5; the connected top plane portion and the bottom plane portion form a water outlet channel, and the muddy water in the simulated slope groove 4 flows into the collecting device 5 through the top plane portion and the bottom plane portion;

[0051] The bracket includes a plate 6 for placing the water tank 1 and a support member located under the plate 6 to support the plate 6; the support member includes four support rods 61 and two cross rods 62, the four support rods 61 are respectively connected to the lower part of the plate 6, and the two cross rods 62 are parallel and respectively located between the two support rods 61.

[0052] The method for testing the variable flow rate water flow erosion of loess slope by using the utility model comprises the following steps:

[0053] Step 1: Place the simulated slope trough 4 on the horizontal ground, lay fine sand in the simulated slope trough 4 to form a fine sand layer 28 to simulate the water permeability of the foundation soil, and according to the preset compaction degree, install the soil sample layer to be tested on the fine sand layer 28, compact it layer by layer to form a sample layer 29, and install the water outlet 30 on the simulated slope trough 4;

[0054] Step 2, open the valve 22, and fill water into the water tank 1 through the water inlet pipe 21, so that the water fills the space between the first baffle plate 13 and the second baffle plate 15, and fills the space between the second baffle plate 15 and the water tank wall through the drain hole 16, and waits for the water in the water tank 1 to overflow the first baffle plate 13 and flow into the space between the first baffle plate 13 and the water tank wall, and continue to fill water, and the water entering the space between the first baffle plate 13 and the water tank wall flows out from the first opening 17, and the door plate 23 is lifted to a preset height, and the water in the water tank flows out from the gap below the door plate 23, and the outflowing water flow rate is calibrated;

[0055] Step 3: After the flow calibration is completed, the simulated slope trough 4 is adjusted to a preset inclination angle through the inclination angle adjustment device, and the slow flow trough 3 is overlapped between the door opening of the water tank 1 and the simulated slope trough 4 containing the fine sand layer 28 and the sample layer 29, so as to form a connected water tank 1, slow flow trough 3 and simulated slope trough 4;

[0056] Step 4: Continue to inject water at a preset constant flow rate or variable flow rate. Turn on the stopwatch while the water flows to the simulated slope groove 4 to start timing. The muddy water after flowing through the sample layer 29 flows into the collection device 5 through the water outlet 30. Take photos of the erosion conditions of the inner slope surface and both sides of the simulated slope groove 4 at preset time intervals.

[0057] Step 5: Wait until the experiment reaches the preset time, end the experiment, measure the slope erosion range, mark the typical erosion area, remove the supernatant after the muddy water in the collection device 5 is left to stand, measure the mass of the eroded soil sample after drying, and calculate the erosion rate.

[0058] The above is only a preferred embodiment of the utility model and does not limit the utility model in any way. Any simple modification, change and equivalent structural change made to the above embodiment according to the technical essence of the utility model still falls within the protection scope of the technical solution of the utility model.

Claims

1. An experimental device for studying water scouring and erosion of loess slopes, characterized in that: The invention comprises a support, a water tank (1), a slow flow trough (3), a simulated inclined trough (4) and a collecting device (5); the water tank (1) is arranged on the support, the slow flow trough (3) is detachably arranged between the water tank (1) and the simulated inclined trough (4), and the collecting device (5) is located below the end of the simulated inclined trough (4) away from the slow flow trough (3); A door opening is provided on one side of the water tank (1) close to the slow flow groove (3), and a door panel (23) is movably mounted on the door opening; A first baffle (13) and a second baffle (15) are arranged in parallel and at intervals in the water tank (1); a drainage hole (16) for water flow to pass through is opened on the surface of the second baffle (15); and the number of the drainage holes (16) is multiple; A first opening (17) and a second opening (20) are provided on the bottom plate of the water tank (1), wherein the first opening (17) is located between the first baffle plate (13) and the wall surface of the water tank (1), and the second opening (20) is located between the first baffle plate (13) and the second baffle plate (15); An inclination angle adjustment device for adjusting the inclination angle of the simulated slope groove (4) is installed at the lower part of the simulated slope groove (4); The simulated slope groove (4) comprises an inner groove surface capable of accommodating a fine sand layer (28) and a sample layer (29).

2. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The slow flow trough (3) is overlapped between the simulated slope trough (4) and the water tank (1).

3. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The first baffle (13) and the second baffle (15) are both vertically arranged in the water tank (1), and the top of the first baffle (13) is a slope (14).

4. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The height difference between the first baffle (13) and the wall surface of the water tank (1) is 2 to 4 cm.

5. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The lower part of the first opening (17) is connected to an overflow pipe (19), the lower part of the second opening (20) is connected to a water inlet pipe (21), and a valve (22) is installed on the water inlet pipe (21).

6. The experimental device for studying water scouring and erosion of loess slope according to claim 5, characterized in that: The tilt angle adjustment device comprises a telescopic rod (25) and a slide groove installed at the bottom of the simulated slope groove (4), wherein the telescopic rod (25) is slidably installed on the slide groove, and the slide groove is located at one end of the simulated slope groove (4) close to the slow flow groove (3).

7. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The simulated slope groove (4) is made of transparent organic glass, and a scale is engraved on the simulated slope groove (4).

8. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The simulated slope trough (4) is detachably provided with a water outlet (30) at the end close to the collecting device (5).

9. The experimental device for studying water scouring and erosion of loess slope according to claim 8, characterized in that: The water outlet portion (30) is protrudingly arranged at the end of the simulated slope groove (4), and the shape of the water outlet portion (30) is a prism-shaped body. The prism-shaped water outlet portion (30) includes a connected top plane portion and a bottom plane portion, the top plane portion and the bottom plane portion are parallel, the area of ​​the top plane portion is less than the area of ​​the bottom plane portion, the top plane portion is installed at the end of the simulated slope groove (4), and the bottom plane portion is directly opposite to the collection device (5).

10. The experimental device for studying water scouring and erosion of loess slope according to claim 1, characterized in that: The bracket comprises a plate member (6) on which the water tank (1) is placed and a support member located under the plate member (6) for supporting the plate member (6).

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