One-dimensional soil column permeation test device and method for in-situ soil under rainfall condition

Abstract

This application provides an in-situ one-dimensional soil column permeability test device and method under rainfall conditions, relating to the field of soil permeability testing. The in-situ one-dimensional soil column permeability test device under rainfall conditions includes: a simulated soil mass and a rainfall simulation system. The simulated soil mass includes a test soil pile, a simulated soil column, and a moisture content sensor. The rainfall simulation system includes a stabilizing support, a simulated rain box, and an adjustment mechanism. The stabilizing support is inserted and fixed within the test soil pile and spans the test trench. The adjustment mechanism is located at the upper end of the stabilizing support. This in-situ one-dimensional soil column permeability test device under rainfall conditions allows for direct observation of permeability rate and permeability deformation, and can obtain the moisture content time-history curve during the test process to study the seepage field changes of the simulated soil column. It also effectively controls the distance between the simulated rain box and the top of the simulated soil column, reducing the impact of rainfall on the boundary of the simulated soil column.

Description

Technical Field

[0001] This application relates to the field of soil permeability testing technology, and more specifically, to an in-situ one-dimensional soil column permeability testing device and method under rainfall conditions. Background Technology

[0002] Soil permeability refers to its ability to allow fluids such as water to pass through it. Like strength and deformation properties, it is a crucial physical, mechanical, and engineering property. The degree of soil permeability is generally measured by the permeability coefficient, which significantly impacts engineering issues such as slope stability, soil consolidation, and the safety of riverbanks and dams. The mechanical mechanism of seepage failure is a result of the interaction between water and soil. When the drag force of water flow disrupts the static equilibrium of soil particles, movement of water containing soil particles occurs within the soil, further affecting the overall stability of the soil. Therefore, research on soil permeability coefficient and seepage failure characteristics is essential.

[0003] In related technologies, soil permeability tests involve flooding the soil with water and measuring the amount of water added and released to calculate soil permeability. However, this method is not suitable for simulating soil permeability under rainfall conditions, detecting the rate of soil permeability, and assessing soil moisture content. The rate of soil permeability and soil moisture content affect soil stability. Summary of the Invention

[0004] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes an in-situ one-dimensional soil column permeability test device and method under rainfall conditions. The in-situ one-dimensional soil column permeability test device under rainfall conditions can directly observe the permeation rate and permeation deformation, and can obtain the water content time history curve during the test process to study the seepage field change law of the soil column. It also has the effect of simulating the distance between the rain box and the top of the simulated soil column to reduce the influence of rainfall on the soil column boundary.

[0005] In a first aspect, according to the embodiments of this application, an in-situ one-dimensional soil column permeability test device under rainfall conditions is provided, comprising: simulated soil and rainfall simulation system.

[0006] The simulated soil includes a test soil pile, a simulated soil column, and a moisture content sensor. A test trench is constructed on the test soil pile, and the simulated soil column is constructed within the test trench. The moisture content sensor is evenly spaced on the side wall of the simulated soil column. The rainfall simulation system includes a stabilizing support, a simulated rain box, and an adjusting mechanism. The stabilizing support is inserted and fixed within the test soil pile and spans the test trench. The adjusting mechanism is located at the upper end of the stabilizing support, and the simulated rain box is installed at the bottom end of the adjusting mechanism. The simulated rain box is located at the upper end of the simulated soil column, and the diameter of the simulated rain box is smaller than the diameter of the simulated soil column. The simulated rain box stores a brilliant blue staining solution.

[0007] According to some embodiments of this application, the stabilizing support includes a stabilizing support, a support rod, a first mounting plate, and a fixing sleeve. The support rod is fixedly connected to the upper side of the stabilizing support near the middle position. The first mounting plate is fixedly connected to the top of the support rod. The fixing sleeve is fixedly connected to the lower side of the first mounting plate. The adjusting mechanism is threadedly connected to the fixing sleeve.

[0008] According to some embodiments of this application, a reinforcing plate is provided between the fixing sleeve, the first mounting plate, and the support rod.

[0009] According to some embodiments of this application, the stabilizing support includes an upper frame and legs, the legs being fixedly connected to the lower side of the upper frame around the perimeter, and the legs being inserted into the test soil pile.

[0010] According to some embodiments of this application, the upper frame and the support leg are detachably connected and fixed by a second mounting plate.

[0011] According to some embodiments of this application, a foot pedal is mounted on the upper side of the upper frame.

[0012] According to some embodiments of this application, the simulated rain box includes a rain box, and a titration hole is provided on the lower side of the rain box.

[0013] According to some embodiments of this application, a connecting plate is fixedly sleeved around the lower periphery of the rain box. The connecting plate is detachably connected to the lower side of the adjustment mechanism. A buffer pad is provided between the connecting plate and the adjustment mechanism, and the connecting plate presses the buffer pad tightly against the adjustment mechanism.

[0014] According to some embodiments of this application, the adjustment mechanism includes an adjustment screw, a fixing part, and a mounting part. The adjustment screw is rotatably connected to the fixing part, the mounting part is fixedly connected to the lower side of the fixing part, and the simulated rain box is fixedly connected to the lower side of the mounting part.

[0015] According to some embodiments of this application, the in-situ one-dimensional soil column permeability test device under rainfall conditions further includes an excavation protection component. The excavation protection component includes an extension member, a soil-breaking sleeve, and a first connecting block. The extension members are joined together to form an extended sleeve. Each extension member includes a semi-annular protective plate, a second connecting block, a first mounting block, and connecting bolts. The second connecting block is fixedly connected to the upper side of the semi-annular protective plate, and the first mounting block is fixedly connected to the lower side of the semi-annular protective plate. The second connecting block of the uppermost extended sleeve is fixedly connected to the mounting part by the connecting bolts. The first mounting block on one side and the second connecting block on the upper side of the adjacent extended sleeve are fixedly connected by the connecting bolts. The joints of the semi-annular guard plates on the adjacent extended sleeves are staggered. The first connecting block is fixedly connected to the upper side of the soil-breaking sleeve. The lower side of the soil-breaking sleeve is provided with an annular cutting edge. The first mounting block of the lowest extended sleeve is fixedly connected to the first connecting block by the connecting bolts. The lower ends of the first connecting block and the second connecting block are both set as sloping surfaces. A positioning rod is fixedly connected to the upper side of the fixing part. The positioning rod slides through the stabilizing support.

[0016] According to some embodiments of this application, the adjusting screw includes an adjusting screw, a limiting plate, two thrust ball bearings, and a clamping nut. The adjusting screw passes through the fixing part, the limiting plate is fixedly connected to the bottom end of the adjusting screw, the two thrust ball bearings are both sleeved on the adjusting screw, and the two thrust ball bearings are respectively located on both sides of the fixing part. The clamping nut is threaded onto the adjusting screw, and the clamping nut presses the two thrust ball bearings and the fixing part against the limiting plate.

[0017] According to some embodiments of this application, a handwheel is fixedly connected to the top of the adjusting screw.

[0018] According to some embodiments of this application, the fixing part includes a fixing plate, the fixing plate has through holes evenly distributed around its periphery, the lower end of the adjusting screw passes through the fixing plate, and the two thrust ball bearings are respectively located on both sides of the fixing plate.

[0019] According to some embodiments of this application, the mounting part includes a mounting sleeve, a third connecting block, and a second mounting block. The third connecting block is fixedly connected to the upper outer wall of the mounting sleeve and is fixedly connected to the fixing plate by the connecting bolt. The second mounting block is fixedly connected to the lower outer wall of the mounting sleeve and is fixedly connected to the second connecting block of the uppermost extended sleeve by the connecting bolt.

[0020] Secondly, according to embodiments of this application, a method for in-situ one-dimensional soil column permeability testing under rainfall conditions is provided, which is conducted using the in-situ one-dimensional soil column permeability testing device under rainfall conditions as described in any one of claims, characterized by comprising the following steps:

[0021] A suitable test site was selected on-site as the test soil pile;

[0022] Stabilizing support structures were erected within the test soil pile;

[0023] Adjust the adjustment mechanism to the upper position of the stable support component;

[0024] Excavate a test trench and a simulated soil column on the test soil pile. The simulated soil column has a diameter of 1 meter and a height of 2 meters.

[0025] Moisture content sensors are installed at equal intervals of 0.5 meters, and the water content sensors are connected to the information collection system.

[0026] Install the simulated rain box and adjust it to a position close to the top of the simulated soil column using the adjustment mechanism;

[0027] Add a Brilliant Blue staining solution (4 g / L food-grade Brilliant Blue staining solution) to the simulated rain box.

[0028] The rate of permeation was observed using a brilliant blue staining solution, and the time-history curve of water content during the experiment was obtained using a water content sensor.

[0029] The beneficial effects of this application are as follows: A stable support structure is erected on the test soil pile to construct a simulated soil column, placing the simulated rain box and the simulated soil column in a relative position. The simulated rain box is smaller than the diameter of the simulated soil column, which affects the impact of rainfall on the boundary. The simulated rain box is installed on an adjustment mechanism, which adjusts the distance between the simulated rain box and the top of the simulated soil column. This reduces the occurrence of simulated rainfall drifting to the sidewalls of the simulated soil column due to environmental factors such as wind when the distance between the simulated rain box and the top of the simulated soil column is large. It also reduces the occurrence of local collapse of the simulated soil column boundary due to simulated rainfall. A brilliant blue staining solution is added to the simulated rain box, allowing for slow titration to replenish the water volume of the simulated soil column. The infiltration rate and signs of infiltration deformation can be directly observed through the brilliant blue staining solution. A water content sensor can acquire the water content time history curve during the experiment to study the seepage field changes of the simulated soil column.

[0030] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a three-dimensional structural schematic diagram of an in-situ one-dimensional soil column permeability test device under rainfall conditions according to an embodiment of this application;

[0033] Figure 2 This is a three-dimensional structural diagram of simulated soil according to an embodiment of this application;

[0034] Figure 3 This is a three-dimensional structural diagram of a rainfall simulation system according to an embodiment of this application;

[0035] Figure 4 This is a three-dimensional structural schematic diagram of the stabilizing support member according to an embodiment of this application;

[0036] Figure 5 This is a three-dimensional structural diagram of a simulated rain box according to an embodiment of this application;

[0037] Figure 6 This is a three-dimensional structural schematic diagram of the excavation protection component according to an embodiment of this application;

[0038] Figure 7 This is a three-dimensional structural schematic diagram of the adjusting screw part according to an embodiment of this application;

[0039] Figure 8 This is a three-dimensional structural diagram of the fixing part according to an embodiment of this application;

[0040] Figure 9 This is a three-dimensional structural diagram of the mounting section according to an embodiment of this application.

[0041] Icons: 100 - Simulated soil; 110 - Test soil pile; 120 - Simulated soil column; 130 - Moisture content sensor; 200 - Rainfall simulation system; 210 - Stabilizing support component; 211 - Stabilizing support; 2111 - Upper frame; 2112 - Support leg; 2113 - Second mounting plate; 212 - Support rod; 213 - First mounting plate; 214 - Fixing sleeve; 215 - Reinforcing plate; 216 - Foot pedal; 220 - Simulated rain box; 221 - Rain box; 222 - Dosing hole; 223 - Connecting plate; 224 - Buffer pad; 230 - Adjustment mechanism; 231 - Adjustment screw; 23 11-Adjusting screw; 2312-Limiting plate; 2313-Thrust ball bearing; 2314-Compression nut; 2315-Handwheel; 232-Fixing part; 2321-Fixing plate; 2322-Through hole; 233-Mounting part; 2331-Mounting sleeve; 2332-Third connecting block; 2333-Second mounting block; 240-Positioning rod; 300-Excavation protection assembly; 310-Additional component; 311-Semi-circular guard plate; 312-Second connecting block; 313-First mounting block; 314-Connecting bolt; 320-Soil-breaking sleeve; 330-Annular cutting edge; 340-First connecting block. Detailed Implementation

[0042] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0043] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0044] The following describes, with reference to the accompanying drawings, an in-situ one-dimensional soil column permeability test apparatus and method under rainfall conditions according to embodiments of this application.

[0045] Please see Figures 1 to 9 This application provides an in-situ one-dimensional soil column permeability test device under rainfall conditions, including: simulated soil 100 and rainfall simulation system 200. The simulated soil 100 is a constructed test soil column model, and the rainfall simulation system 200 is used to simulate rainfall so as to observe the permeability test under rainfall conditions.

[0046] Please see Figure 2The simulated soil body 100 includes a test soil pile 110, a simulated soil column 120, and a moisture content sensor 130. A test trench is constructed on the test soil pile 110, the simulated soil column 120 is constructed in the test trench, and the moisture content sensor 130 is equally spaced on the side wall of the simulated soil column 120.

[0047] Please see Figure 3 The rainfall simulation system 200 includes a stabilizing support 210, a simulated rain box 220, and an adjusting mechanism 230. The stabilizing support 210 is inserted and fixed inside the test soil pile 110 and spans the test trench. The adjusting mechanism 230 is located at the upper end of the stabilizing support 210. The simulated rain box 220 is installed at the bottom end of the adjusting mechanism 230. The simulated rain box 220 is located at the upper end of the simulated soil column 120, and the diameter of the simulated rain box 220 is smaller than the diameter of the simulated soil column 120. The simulated rain box 220 contains a brilliant blue staining solution. A stabilizing support 210 is erected on the test soil pile 110 to construct a simulated soil column 120, positioning the simulated rain box 220 and the simulated soil column 120 in relative positions. The simulated rain box 220 is smaller than the diameter of the simulated soil column 120 to minimize the impact of rainfall on the boundary. The simulated rain box 220 is installed on an adjustment mechanism 230, which adjusts the distance between the simulated rain box 220 and the top of the simulated soil column 120, reducing the impact of environmental factors such as wind when the distance between the simulated rain box 220 and the top of the simulated soil column 120 is too large. This design prevents simulated rainfall from drifting to the sidewalls of the simulated soil column 120, reducing the likelihood of localized collapse at the boundary of the simulated soil column 120 due to simulated rainfall. A brilliant blue staining solution is added to the simulated rain box 220, allowing for slow titration to replenish the water supply to the simulated soil column 120. The brilliant blue staining solution allows direct observation of the seepage rate and signs of seepage deformation. A water content sensor 130 acquires the water content time-history curve during the experiment, enabling the study of seepage field changes in the simulated soil column 120. The adjustment mechanism 230 includes an adjusting screw 231, a fixing part 232, and a mounting part 233. The adjusting screw 231 is rotatably connected to the fixing part 232, the mounting part 233 is fixedly connected to the lower side of the fixing part 232, and the simulated rain box 220 is fixedly connected to the lower side of the mounting part 233. The rotating adjusting screw 231, through the thread transmission principle, drives the fixing part 232 and the mounting part 233 to rise and fall, thereby driving the simulated rain box 220 to rise and fall, so as to reduce the situation where the simulated rain box 220 is too far from the top of the simulated soil column 120, and the simulated rain falls onto the side wall of the simulated soil column 120 due to the influence of environmental wind force, etc.

[0048] Please see Figure 4The stabilizing support component 210 includes a stabilizing support 211, a support rod 212, a first mounting plate 213, and a fixing sleeve 214. The support rod 212 is fixedly connected to the upper side of the stabilizing support 211 near the middle. The first mounting plate 213 is fixedly connected to the top of the support rod 212. The fixing sleeve 214 is fixedly connected to the lower side of the first mounting plate 213. An adjusting mechanism 230 is threadedly connected to the fixing sleeve 214. The stabilizing support 211 is erected on the test soil pile 110. The support rod 212 raises the mounting plate 213, reserving space for the simulated rain box 220 to move and install. A reinforcing plate 215 is provided between the fixing sleeve 214, the first mounting plate 213, and the support rod 212. The reinforcing plate 215 enhances the strength between the fixing sleeve 214, the first mounting plate 213, and the support rod 212. The stabilizing support 211 includes an upper frame 2111 and support legs 2112. The support legs 2112 are fixedly connected to the lower side of the upper frame 2111 around its perimeter and are inserted into the test soil pile 110. When installing the stabilizing support 211, first determine the position of the support legs 2112, drive the support legs 2112 into the test soil pile 110, ensuring the upper ends of the support legs are at the same height, and then install the upper frame 2111 onto the support legs 2112. The upper frame 2111 and the support legs 2112 are detachably connected and fixed via a second mounting plate 2113. The upper frame 2111 and the second mounting plate 2113 of the support legs 2112 are fixed together with fastening bolts and nuts, facilitating the installation of the upper frame 2111 and the support legs 2112. A foot pedal 216 is mounted on the upper side of the upper frame 2111. Foot pedal 216 is attached to the upper frame 2111 so that personnel can stand. When excavating and constructing test trenches and simulated soil columns 120, foot pedal 216 can be removed first.

[0049] Please see Figure 5 The simulated rain box 220 includes a rain box 221, with a titration hole 222 on its lower side. Brilliant blue staining solution is added to the rain box 221 and slowly titrated into the simulated soil column 120 through the titration hole 222. A connecting plate 223 is fixedly fitted around the lower periphery of the rain box 221. The connecting plate 223 is detachably connected to the lower side of the adjusting mechanism 230. A buffer pad 224 is placed between the connecting plate 223 and the adjusting mechanism 230, with the connecting plate 223 pressing the buffer pad 224 tightly against the adjusting mechanism 230. The connecting plate 223 is bolted to the adjusting mechanism 230; loosening the bolts allows the connecting plate 223 to be removed. The buffer pad 224 reduces wear and seal between the connecting plate 223 and the adjusting mechanism 230, minimizing the possibility of Brilliant Blue staining solution leaking from the rain box 221 during the filling process and dripping from the connection between the connecting plate 223 and the adjusting mechanism 230.

[0050] Please see Figure 6In related technologies, the in-situ one-dimensional soil column permeability test device under rainfall conditions requires the construction of a simulated soil column before the test. However, when artificially constructing the simulated soil column, it is easy to cause the simulated soil column to collapse, resulting in construction failure. How to protect the simulated soil column during construction has become a technical problem that needs to be solved. If an independent protection scheme is adopted, it is necessary to rebuild the support and the pushing structure of the protection structure. How to utilize the existing structure to add a protective structure is also a technical problem that needs to be solved at the same time.

[0051] To address this technical problem, the inventors, through long-term practical research, solved the issue. Specifically, the in-situ one-dimensional soil column permeability test device under rainfall conditions also includes an excavation protection component 300. The excavation protection component 300 includes an extension piece 310, a soil-breaking sleeve 320, and a first connecting block 340. The extension pieces 310 are connected to each other to form an extended sleeve. Each extension piece 310 includes a semi-annular protective plate 311, a second connecting block 312, a first mounting block 313, and connecting bolts 314. The second connecting block 312 is fixedly connected to the upper side of the semi-annular protective plate 311, and the first mounting block 313 is fixedly connected to the lower side of the semi-annular protective plate 311. The second connecting block 312 of the uppermost extended sleeve is fixedly connected to the mounting part 233 by connecting bolts 314. The first mounting block 313 on the lower side of the long sleeve and the second connecting block 312 on the upper side of the adjacent extended sleeve are fixedly connected by connecting bolts 314. The joints of the upper semi-circular guard plates 311 of the adjacent extended sleeves are staggered. The first connecting block 340 is fixedly connected to the upper side of the soil-breaking sleeve 320. The lower side of the soil-breaking sleeve 320 is provided with an annular cutting edge 330. The first mounting block 313 of the lowest extended sleeve is fixedly connected to the first connecting block 340 by connecting bolts 314. The lower ends of the first connecting block 340 and the second connecting block 312 are both set as sloping surfaces. The upper side of the fixing part 232 is fixedly connected with a positioning rod 240. The positioning rod 240 slides through the stabilizing support member 210.Before constructing the simulated soil column, the construction location is selected, and a stable support component 210 is erected. First, the first connecting block 340 on the breaking sleeve 320 is connected to the installation part 233 via connecting bolts 314. The adjusting screw part 231 is rotated, and through the threaded transmission principle, the adjusting screw part 231 drives the fixing part 232 and the installation part 233 to fall. The positioning rod 240 maintains the position of the breaking sleeve 320, reducing the impact of the breaking sleeve 320's rotation on the formation of the simulated soil column 120. The installation part 233 drives the annular cutting edge 330 of the breaking sleeve 320 to break through the test soil pile 110. When the breaking sleeve 320 penetrates deep into the test soil… After stacking 110, release the connecting bolt 314, rotate the adjusting screw 231 in the reverse direction, and the mounting part 233 rises. The extended sleeve formed by the butt joint of the semi-annular guard plate 311 is then connected to the first connecting block 340 on the upper side of the soil-breaking sleeve 320 via the connecting bolt 314. Specifically, the first mounting block 313 and the first connecting block 340 are fixed by the connecting bolt 314. Adjust the position of the mounting part 233 so that the second connecting block 312 on the upper side of the semi-annular guard plate 311 is connected to the mounting part 233 via the connecting bolt 314. Continue rotating the adjusting screw 231, which in turn moves the semi-annular guard plate... 311 and the excavating sleeve 320 continue to break through the test soil pile 110. After the semi-circular protective plate 311 penetrates into the test soil pile 110, the remaining semi-circular protective plates 311 are joined to form an extended sleeve, following the steps above. During the process of joining the extended sleeves formed by joining the remaining semi-circular protective plates 311, attention should be paid to the staggered arrangement of the joints of the semi-circular protective plates 311 on adjacent extended sleeves to reduce the occurrence of the semi-circular protective plates 311 spreading out. Soil cleaning of the outer wall of the excavating sleeve 320 and the extended sleeve can be carried out simultaneously with the penetration of the excavating sleeve 320 into the soil, or after the excavating sleeve 320 has penetrated to the required depth. After cleaning, the cleared space forms a test trough. When the simulated soil column 120 is formed, it is protected by the semi-annular protective plate 311 and the soil-breaking sleeve 320 during the construction of the simulated soil column 120, reducing the possibility of collapse during the construction of the simulated soil column 120, thereby reducing the occurrence of rework due to construction failure. Furthermore, the pushing of the semi-annular protective plate 311 and the soil-breaking sleeve 320 is achieved through the adjustment structure of the simulated rain box 220, and the simulated rain box 220 can be supported by the stabilizing support 210. The protective structure can be completed by adding it to the existing pushing structure, thereby simplifying the structure.

[0052] Please see Figure 7The adjusting screw section 231 includes an adjusting screw 2311, a limiting plate 2312, two thrust ball bearings 2313, and a clamping nut 2314. The adjusting screw 2311 passes through the fixing part 232. The limiting plate 2312 is fixedly connected to the bottom end of the adjusting screw 2311. Both thrust ball bearings 2313 are sleeved on the adjusting screw 2311, and the two thrust ball bearings 2313 are respectively located on both sides of the fixing part 232. The clamping nut 2314 is threaded onto the adjusting screw 2311, and the clamping nut 2314 presses the two thrust ball bearings 2313 and the fixing part 232 against the limiting plate 2312. A handwheel 2315 is fixedly connected to the top end of the adjusting screw 2311. The adjusting screw 2311 is rotated by the handwheel 2315. During the rotation of the adjusting screw 2311, the fixed part 232 is kept stable by the thrust ball bearing 2313, so as to achieve the purpose of the adjusting screw part 231 being rotatably connected to the fixed part 232.

[0053] Please see Figure 8 The fixing part 232 includes a fixing plate 2321, with through holes 2322 evenly distributed around its periphery. The lower end of the adjusting screw 2311 passes through the fixing plate 2321, and two thrust ball bearings 2313 are located on both sides of the fixing plate 2321. Brilliant blue staining solution can be added through the through holes 2322.

[0054] Please see Figure 9 The mounting part 233 includes a mounting sleeve 2331, a third connecting block 2332, and a second mounting block 2333. The third connecting block 2332 is fixedly connected to the upper outer wall of the mounting sleeve 2331 and is fixedly connected to the fixing plate 2321 by connecting bolts 314. The second mounting block 2333 is fixedly connected to the lower outer wall of the mounting sleeve 2331 and is fixedly connected to the second connecting block 312 of the uppermost extended sleeve by connecting bolts 314.

[0055] Please see Figures 1 to 9 This application also provides a method for in-situ one-dimensional soil column permeability testing under rainfall conditions, which utilizes an in-situ one-dimensional soil column permeability testing device under rainfall conditions and includes the following steps:

[0056] A suitable test site was selected on-site as the test soil pile 110;

[0057] A stabilizing support structure 210 was installed inside the test soil pile 110;

[0058] Adjust the adjustment mechanism 230 to the upper position of the stabilizing bracket 210;

[0059] A test trench and a simulated soil column 120 were excavated on the test soil pile 110. The simulated soil column 120 had a diameter of 1 meter and a height of 2 meters.

[0060] Moisture content sensors 130 are installed at equal intervals of 0.5 meters, and the moisture content sensors 130 are connected to the information collection system.

[0061] Install the simulated rain box 220 and adjust the simulated rain box 220 to a position close to the top of the simulated soil column 120 using the adjustment mechanism 230;

[0062] Add a brilliant blue staining solution to the simulated rain box 220. The brilliant blue staining solution is a food-grade brilliant blue staining solution with a concentration of 4 g / L.

[0063] The rate of permeation was observed using a brilliant blue staining solution, and the water content time-history curve during the experiment was obtained using a water content sensor 130.

[0064] The experimental system consists of an in-situ simulated soil column 120, a water supply system, and a volumetric moisture content acquisition and collection system. During the experiment, a suitable experimental site was selected, and a simulated soil column 120 with a diameter of approximately 1 meter and a height of approximately 2 meters was constructed. A simulated rain box 220 with a burette hole 222 at the bottom was placed on top of the simulated soil column 120 via a stabilizing support 210. The diameter of the simulated rain box 220 was slightly smaller than that of the soil column, allowing for slow titration to replenish the simulated soil column 120 with water. The experimental solution used was a 4 g / L food-grade brilliant blue staining solution, which did not affect the infiltration process and was environmentally friendly, facilitating the observation of infiltration deformation. Four volumetric moisture content sensors were evenly arranged on the side of the soil column to acquire the moisture content time-history curve during the experiment, enabling the study of the seepage field changes in the soil column.

[0065] Specifically, the working principle of the in-situ one-dimensional soil column permeability test device and method under this rainfall condition is as follows: When installing the stable support component 210, first determine the position of the support leg 2112, drive the support leg 2112 into the test soil pile 110, ensuring the upper ends of the support legs 2112 are at the same height, install the upper frame 2111 on the support leg 2112, and raise the mounting plate 213 using the support rod 212 to reserve space for the rain box 221 to move and install. Construct a simulated soil column 120, ensuring the rain box 221 and the simulated soil column 120 are in relative positions. The diameter of the rain box 221 is smaller than the diameter of the simulated soil column 120, affecting the impact of rainfall on the boundary. Install the rain box 221 on the mounting part 233, rotate the adjusting screw part 231, and through the thread transmission principle, adjust the screw part 231 to drive the fixed... The components 232 and 233 rise and fall, thereby causing the rain box 221 to rise and fall, adjusting the position of the rain box 221 relative to the top of the simulated soil column 120. This reduces the occurrence of simulated rain falling onto the side wall of the simulated soil column 120 due to environmental factors such as wind when the distance between the rain box 221 and the top of the simulated soil column 120 is large, and also reduces the occurrence of local collapse of the boundary of the simulated soil column 120 due to simulated rain. Brilliant blue staining solution is added to the rain box 221, and water is replenished to the simulated soil column 120 by slow titration. The infiltration rate and signs of infiltration deformation can be directly observed through the brilliant blue staining solution. The water content sensor 130 can acquire the water content time history curve during the test to study the seepage field change law of the simulated soil column 120.

[0066] Before simulating the soil column construction, the construction location is selected, and a stable support component 210 is erected. First, the first connecting block 340 on the breaking sleeve 320 is connected to the second mounting block 2333 of the mounting sleeve 2331 via connecting bolts 314. The third connecting block 2332 is fixedly connected to the fixed plate 2321 via connecting bolts 314. Rotating the adjusting screw 2311, through the threaded transmission principle, causes the fixed plate 2321 and the mounting sleeve 2331 to fall. The positioning rod 240 maintains the position of the breaking sleeve 320, reducing the impact of the breaking sleeve 320's rotation on the formation of the simulated soil column 120. The mounting sleeve 2331 drives the annular cutting edge 330 of the breaking sleeve 320 to break through the test soil pile 110. After the breaking sleeve 320 penetrates deep into the test soil pile 110, the connecting bolts 314 are released, and the adjusting screw 2311 is rotated in the opposite direction, causing the mounting sleeve 2331 to rise and raise the semi-annular protective plate 311. The extended sleeve formed by the butt joint is connected to the first connecting block 340 on the upper side of the soil-breaking sleeve 320 via connecting bolts 314. Specifically, the first mounting block 313 and the first connecting block 340 are fixed by connecting bolts 314. The position of the mounting sleeve 2331 is adjusted so that the second connecting block 312 on the upper side of the semi-annular guard plate 311 is connected to the mounting sleeve 2331 via connecting bolts 314. The adjusting screw 2311 is rotated, and the adjusting screw 2311 drives the semi-annular guard plate 311 and the soil-breaking sleeve 320 to continue breaking the test soil pile 110. After the semi-annular guard plate 311 penetrates into the test soil pile 110, the extended sleeves formed by the butt joints of the remaining semi-annular guard plates 311 are connected in the same manner as above. During the connection of the extended sleeves formed by the butt joints of the remaining semi-annular guard plates 311, attention should be paid to the staggered arrangement of the butt joints of the semi-annular guard plates 311 on the adjacent extended sleeves to reduce the occurrence of the semi-annular guard plates 311 spreading out.

[0067] During the process of the excavating sleeve 320 breaking through the test soil pile 110, the installation sleeve 2331 can serve as a protective structure for extending the excavating sleeve 320 to penetrate deeper into the test soil pile 110. The soil cleaning of the excavating sleeve 320 and the outer wall of the extended sleeve can be carried out simultaneously with the excavating sleeve 320 penetrating deeper into the soil, or it can be carried out after the excavating sleeve 320 has reached the required depth. The space cleared out forms a test trench. When the simulated soil column 120 is formed, it is protected by the semi-circular protective plate 311 and the excavating sleeve 320 during the construction of the simulated soil column 120, reducing the possibility of collapse during the construction of the simulated soil column 120, thereby reducing the occurrence of construction failure and rework. Furthermore, the pushing of the semi-circular protective plate 311 and the excavating sleeve 320 is carried out through the adjustment structure of the rain box 221, and the rain box 221 can be supported by the stabilizing support 210. The construction of the protective structure can be completed by adding it to the existing pushing structure, thereby achieving the purpose of simplifying the structure.

[0068] It should be noted that the specific model and specifications of the moisture content sensor 130 need to be selected and determined according to the actual specifications of the device. The specific selection calculation method adopts the existing technology in this field, so it will not be elaborated in detail.

[0069] The power supply and operating principle of the moisture content sensor 130 are clear to those skilled in the art and will not be described in detail here.

[0070] The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

Claims

1. A one-dimensional soil column permeability test device for in-situ soil under rainfall conditions, characterized in that, include: The simulated soil body includes a test soil pile, a simulated soil column, and a moisture content sensor. A test trench is constructed on the test soil pile, the simulated soil column is constructed inside the test trench, and the moisture content sensor is equally spaced on the side wall of the simulated soil column. A rainfall simulation system includes a stabilizing support, a simulated rain box, and an adjusting mechanism. The stabilizing support is inserted and fixed within the test soil pile and spans the test trench. The adjusting mechanism is located at the upper end of the stabilizing support, and the simulated rain box is installed at the bottom end of the adjusting mechanism. The simulated rain box is located at the upper end of the simulated soil column, and the diameter of the simulated rain box is smaller than the diameter of the simulated soil column. The simulated rain box contains a brilliant blue staining solution. The adjusting mechanism includes an adjusting screw, a fixing part, and an mounting part. The adjusting screw is rotatably connected to the fixing part, and the mounting part is fixedly connected to the lower side of the fixing part. An excavation protection component includes an extension piece, a soil-breaking sleeve, and a first connecting block. The extension pieces are joined together to form an extended sleeve. Each extension piece includes a semi-annular guard plate, a second connecting block, a first mounting block, and connecting bolts. The second connecting block is fixedly connected to the upper side of the semi-annular guard plate, and the first mounting block is fixedly connected to the lower side of the semi-annular guard plate. The second connecting block of the uppermost extended sleeve is fixedly connected to the mounting part by the connecting bolts. The first mounting block on the lower side of the extended sleeve and the second connecting block on the upper side of the adjacent extended sleeve are fixedly connected by the connecting bolts. The joints of the semi-annular guard plates on adjacent extended sleeves are staggered. The first connecting block is fixedly connected to the upper side of the soil-breaking sleeve. The lower side of the soil-breaking sleeve is provided with an annular cutting edge. The first mounting block of the lowermost extended sleeve is fixedly connected to the first connecting block by the connecting bolts. The lower ends of both the first connecting block and the second connecting block are set as sloping surfaces. A positioning rod is fixedly connected to the upper side of the fixing part, and the positioning rod slides through the stabilizing support component.

2. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 1, characterized in that, The stabilizing support includes a stabilizing bracket, a support rod, a first mounting plate, and a fixing sleeve. The support rod is fixedly connected to the upper side of the stabilizing bracket near the middle. The first mounting plate is fixedly connected to the top of the support rod. The fixing sleeve is fixedly connected to the lower side of the first mounting plate. The adjusting mechanism is threadedly connected to the fixing sleeve.

3. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 2, characterized in that, A reinforcing plate is provided between the fixed sleeve, the first mounting plate, and the support rod.

4. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 2, characterized in that, The stabilizing support includes an upper frame and legs. The legs are fixedly connected to the lower side of the upper frame and inserted into the test soil pile.

5. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 4, characterized in that, The upper frame and the support leg are detachably connected and fixed by a second mounting plate.

6. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 5, characterized in that, A foot pedal is mounted on the upper side of the upper frame.

7. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 1, characterized in that, The simulated rain box includes a rain box, and a titration hole is provided on the lower side of the rain box.

8. The in-situ one-dimensional soil column permeability test device under rainfall conditions according to claim 7, characterized in that, A connecting plate is fixedly sleeved around the lower periphery of the rain box. The connecting plate is detachably connected to the lower side of the adjustment mechanism. A buffer pad is provided between the connecting plate and the adjustment mechanism. The connecting plate presses the buffer pad tightly against the adjustment mechanism.

9. A method for in-situ one-dimensional soil column permeability testing under rainfall conditions, comprising using the in-situ one-dimensional soil column permeability testing apparatus under rainfall conditions as described in any one of claims 1-8, characterized in that... Includes the following steps: A suitable test site was selected on-site as the test soil pile; Stabilizing support structures were erected within the test soil pile; Adjust the adjustment mechanism to the upper position of the stable support component; Excavate a test trench and simulated soil column on the test soil pile. First, connect the first connecting block of the soil-breaking sleeve to the installation part using connecting bolts. Rotate the adjusting screw, and through the thread transmission principle, the adjusting screw drives the fixing part and the installation part to fall. The positioning rod maintains the position of the soil-breaking sleeve, reducing the impact of the rotation of the soil-breaking sleeve on the formation of the simulated soil column. The installation part drives the annular cutting edge of the soil-breaking sleeve to break the test soil pile. After the soil-breaking sleeve penetrates deep into the test soil pile, release the connecting bolts and rotate the adjusting screw in the opposite direction. The installation part rises, and the extended sleeve formed by the butt joint of the semi-annular guard plate is connected to the first connecting block on the upper side of the soil-breaking sleeve using connecting bolts. Specifically, the first installation block and the first connecting block are fixed with connecting bolts. Adjust the position of the installation part so that the second connecting block on the upper side of the semi-annular guard plate is connected to the... The installation unit continues to rotate the adjusting screw, which drives the semi-circular protective plate and the soil-breaking sleeve to continue breaking the test soil pile. After the semi-circular protective plate penetrates the test soil pile, the extension sleeve formed by connecting the remaining semi-circular protective plates is connected according to the above steps. During the connection of the extension sleeve formed by connecting the remaining semi-circular protective plates, attention should be paid to the staggered arrangement of the joints of the semi-circular protective plates on the adjacent extension sleeves to reduce the occurrence of the semi-circular protective plates spreading out. Soil cleaning of the outer wall of the soil-breaking sleeve and the extension sleeve can be carried out simultaneously with the soil-breaking sleeve penetrating the soil, or it can be carried out after the soil-breaking sleeve has reached the required depth. The space cleared out forms the test trench. When the simulated soil column is formed, it is protected by the semi-circular protective plate and the soil-breaking sleeve during the construction of the simulated soil column. The simulated soil column has a diameter of 1 meter and a height of 2 meters. Moisture content sensors are installed at equal intervals of 0.5 meters, and the water content sensors are connected to the information collection system. Install the simulated rain box and adjust it to a position close to the top of the simulated soil column using the adjustment mechanism; Add a Brilliant Blue staining solution (4 g / L food-grade Brilliant Blue staining solution) to the simulated rain box. The rate of permeation was observed using a brilliant blue staining solution, and the time-history curve of water content during the experiment was obtained using a water content sensor.

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