A contaminated site barrier manufacturing device and refined manufacturing method

Abstract

The present invention provides a contaminated site barrier manufacturing device and a refined manufacturing method, the manufacturing device includes a walking base, a vibrating traction arm and a stirring assembly, the vibrating traction arm is connected to the walking base through a rotating drive assembly, and the stirring assembly is connected to the vibrating traction arm through a vibrating drive assembly; the vibrating traction arm can drive the stirring assembly to rotate relative to the walking base, and the stirring assembly can vibrate relative to the vibrating traction arm along the axial direction of the stirring assembly. The contaminated site barrier manufacturing device and a refined manufacturing method provided by the present invention improve the mixing efficiency of the gel material and the in-situ soil, and improve the homogeneity of the barrier.

Description

Technical Field

[0001] The present invention belongs to the technical field of building structures in contaminated sites, and in particular, relates to a contaminated site isolation barrier manufacturing device and a refined manufacturing method. Background Art

[0002] Contaminated site barrier can effectively control the migration and diffusion of pollutants in soil and groundwater, and is currently a commonly used contaminated site remediation technology. Barriers usually use highly alkaline cementitious materials such as cement to treat the in-situ soil, reduce the permeability coefficient of the in-situ soil, and thus control the migration of pollutants to the environment outside the site.

[0003] At present, the construction of barrier barriers mainly relies on the following processes and equipment: backfilling barrier materials after trenching with engineering excavators, mixing in-situ soil and cementitious materials with mixing piles, etc. However, these construction processes and the equipment used are often heavy equipment and occupy a large area; the in-situ soil and cementitious materials are mixed unevenly, resulting in poor homogeneity of the barrier barrier and unsatisfactory barrier effect; in addition, the existing construction equipment also has the disadvantages of high energy consumption and low construction efficiency. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a contaminated site barrier manufacturing device and a refined manufacturing method to improve the mixing efficiency of the gel material and the in-situ soil and enhance the homogeneity of the barrier.

[0005] To solve the above technical problems, the embodiments of the present invention adopt the following technical solutions:

[0006] In the first aspect, an embodiment of the present invention provides a device for manufacturing a contaminated site isolation barrier, comprising a walking base, a vibrating traction arm and a stirring assembly, wherein the vibrating traction arm is connected to the walking base via a rotating drive assembly, and the stirring assembly is connected to the vibrating traction arm via a vibrating drive assembly; the vibrating traction arm can drive the stirring assembly to rotate relative to the walking base, and the stirring assembly can vibrate along the axial direction of the stirring assembly relative to the vibrating traction arm.

[0007] As a further improvement of an embodiment of the present invention, the stirring assembly includes a stirring arm and a stirring tool, the stirring arm is installed on a vibrating traction arm through a vibration drive assembly, and the stirring tool is installed on the stirring arm; the stirring tool includes a power wheel, a guide wheel, a bracket, a chain, a stirring blade and a stirring drive member; the bracket and the stirring arm are fixedly connected; the power wheel and the guide wheel are respectively installed at both ends of the bracket, and the chain is mounted on the power wheel and the guide wheel; the stirring drive member is connected to the power wheel for driving the power wheel to rotate; the stirring blade is fixedly connected to the chain.

[0008] As a further improvement of an embodiment of the present invention, the stirring assembly is slidably connected to the vibrating traction arm; the vibration drive assembly includes two counter-rotating motors and two power shafts, and the two motors are installed on the vibrating traction arm; one end of the two power shafts is respectively connected to the two motors, and the other end is respectively connected to the two elliptical limit holes on the stirring assembly.

[0009] As a further improvement of the embodiment of the present invention, it also includes a first discharge pipe and a second discharge pipe, and the first discharge pipe and the second discharge pipe are fixed on the stirring assembly.

[0010] In a second aspect, an embodiment of the present invention further provides a method for finely manufacturing a contaminated site barrier, using the contaminated site barrier manufacturing device provided in the first aspect; the method comprises:

[0011] Step 10, performing segmented manufacturing along a preset extension direction of the barrier according to a preset depth, a preset thickness and a preset length of the barrier;

[0012] Among them, manufacturing a single-stage barrier segment specifically includes:

[0013] Step 201, the walking base moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier to the end point of the single-stage barrier segment; during the movement, the stirring assembly mixes the gel material with the in-situ soil to form a first-stage barrier segment;

[0014] Step 202, start the vibration drive assembly, so that the stirring assembly vibrates along the axial direction of the stirring assembly relative to the vibration traction arm; the walking base moves from the end point of the single-stage barrier segment to the starting point of the single-stage barrier segment along the preset extension direction of the barrier; during the movement, the stirring assembly mixes the air with the first-stage barrier segment to form a second-stage barrier segment;

[0015] Step 203, the walking base moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier barrier to the end point of the single-stage barrier segment; during the movement, the stirring component mixes the second-stage barrier segment to form a third-stage barrier segment; and the manufacture of the single-stage barrier segment is completed.

[0016] As a further improvement of an embodiment of the present invention, in step 202 and step 203, the vibration frequency of the stirring assembly is set according to the in-situ geological conditions of the location where the single-section barrier segment is located; in step 202, the moving speed of the walking base is set according to the in-situ geological conditions of the location where the single-section barrier segment is located.

[0017] As a further improvement of the embodiment of the present invention, the vibration frequency of the stirring assembly is set according to the in-situ geological conditions of the location of the single-stage barrier segment, specifically including:

[0018] Step 211, detecting and obtaining the foundation bearing capacity of the starting point and the end point of the single-segment barrier segment; obtaining the top surface depth and the bottom surface depth of each soil layer at the starting point according to the foundation bearing capacity of the starting point; obtaining the top surface depth and the bottom surface depth of each soil layer at the end point according to the foundation bearing capacity of the end point; wherein the preset depth of the barrier is used as the bottom surface depth of the soil layer where the bottom end of the barrier at the starting point and the end point is located;

[0019] Step 212, obtaining the thickness of each soil layer at the starting point according to the top surface depth and the bottom surface depth of each soil layer at the starting point; obtaining the thickness of each soil layer at the end point according to the top surface depth and the bottom surface depth of each soil layer at the end point; obtaining the average thickness of each soil layer between the starting point and the end point according to the thickness of each soil layer at the starting point and the thickness of each soil layer at the end point;

[0020] Step 213, obtaining the centerline depth of each soil layer at the starting point according to the top surface depth and the bottom surface depth of each soil layer at the starting point; obtaining the centerline depth of each soil layer at the end point according to the top surface depth and the bottom surface depth of each soil layer at the end point; obtaining the average foundation bearing capacity of each soil layer between the starting point and the end point according to the foundation bearing capacity of the centerline depth of each soil layer at the starting point and the centerline depth of each soil layer at the end point;

[0021] Step 214, using formula (1) to calculate the vibration frequency of the stirring assembly when manufacturing a single-stage barrier:

[0022] Formula (1)

[0023] In the formula, It represents the vibration frequency of the stirring assembly when manufacturing the i-th barrier segment, in Hz; It represents the average thickness of the first soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the first soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the second soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the second soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the nth soil layer between the starting point and the end point of the i-th barrier segment, in meters; It represents the average foundation bearing capacity of the nth soil layer between the starting point and the end point of the i-th barrier segment, in MPa; Indicates the preset depth of the barrier; Indicates the first preset coefficient, in Hz; Indicates the second preset coefficient, in Hz·MPa-1 ; represents the total number of barrier segments, and n represents the total number of soil layers.

[0024] As a further improvement of the embodiment of the present invention, according to the in-situ geological conditions of the location of the barrier, the moving speed of the walking base is calculated using formula (2):

[0025] Formula (2)

[0026] In the formula, represents the moving speed of the walking base in step 202 when manufacturing the i-th barrier segment, in m / min; Indicates the third preset coefficient, in m / min; Indicates the fourth preset coefficient, the unit is m·min -1 MPa -1 .

[0027] As a further improvement of the embodiment of the present invention, The value range is 30 to 60. The value range is 8 to 12. The value range is 1.8~2.2, The value range is 0.08~0.12.

[0028] As a further improvement of the embodiment of the present invention, in step 201, the moving speed of the walking base is 1.0 m / min; in step 203, the moving speed of the walking base is 2.0 m / min.

[0029] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0030] (1) The present invention provides a device for manufacturing a barrier for contaminated sites. The stirring assembly is connected to the vibrating traction arm through a vibrating drive assembly. During mixing, the vibration of the stirring assembly improves the mixing efficiency of the cementitious material and the in-situ soil, improves the homogeneity of the barrier, and effectively improves the effect of blocking pollutants. At the same time, it can shorten the mixing time and improve manufacturing efficiency. The device occupies a small construction area and does not require on-site installation. Construction can start as soon as the device arrives at the site, which can effectively improve manufacturing efficiency and is suitable for sites with limited working areas. In addition, the vibrating traction arm is connected to the walking base through a rotating drive assembly. When not in operation, the stirring assembly can be fixed in the horizontal direction with the vibrating traction arm and moved with the walking base without disassembling the stirring assembly, which has good transfer efficiency.

[0031] (2) The refined manufacturing method of the contaminated site barrier provided by the present invention manufactures the barrier in sections; when manufacturing a single-section barrier segment, the walking base first moves from the starting point of the single-section barrier segment to the end point of the single-section barrier segment, and the stirring component mixes the gel material with the in-situ soil to form a first-stage barrier segment; then the vibration drive component is turned on to make the stirring component vibrate along the axial direction of the stirring component; the walking base moves from the end point of the single-section barrier segment to the starting point of the single-section barrier segment, and the stirring component mixes the air with the first-stage barrier segment to form a second-stage barrier segment; finally, the walking base moves from the starting point of the single-section barrier segment to the end point of the single-section barrier segment, and the stirring component mixes the second-stage barrier segment to form a third-stage barrier segment; thereby completing the manufacturing of the single-section barrier segment. The present invention uses three stages of mixing to respectively mix the gel material with the in-situ soil, intensively mix the gel material with the in-situ soil, and remove bubbles from the gel material and the in-situ soil. In the first stage, the gel material is first mixed with the in-situ soil to achieve the mixing of the gel material with the sand, silt and clay in the in-situ soil. Due to the large spatial distribution of the above components, it is not necessary to turn on the vibration mode of the stirring component to achieve the initial mixing of the above components, so that the gel material, sand, silt and clay are distributed throughout the depth of the barrier. Since the stratum distribution has not been completely broken in the early stage of mixing, if air is injected during this process, it will cause disturbance of groundwater in the permeable layer and pollution migration, thereby increasing the risk of pollution migration on the site, so air is not introduced in the first stage. In the second stage, the gel material, sand, silt and clay have been initially mixed, the permeable layer has disappeared, and the barrier has a certain barrier capacity. Therefore, the introduction of air can increase the fluidity of the barrier material and improve the mixing efficiency, and this process will not cause large-scale migration of polluted groundwater. In addition, in this stage, the sand particles have been dispersed in fine-grained clay (silt and clay) and colloids (cementitious materials), and it is difficult to further disperse them by conventional mixing. After the stirring component turns on the vibration mode, the colloids produced by the cementitious materials and the agglomerates formed with the fine particles are gradually transformed into suspensions under the action of vibration cutting, increasing their fluidity. In this stage, by injecting air and turning on the vibration mode of the stirring component, the barrier can be fully mixed and the energy can be fully utilized. The third stage is mainly to expel the bubbles in the barrier under more uniform mixing conditions. Since the injected air will exist in the barrier and form cavities and holes, thereby creating a dominant channel for the migration of pollutants, the bubbles in it need to be expelled. It is carried out in the vibration mode, which can prevent the barrier material from being converted from a suspension to a network colloid, thereby reducing the difficulty of expelling bubbles.

[0032] (3) The refined manufacturing method of the contaminated site barrier provided by the present invention determines the vibration frequency of the mixing component when constructing each barrier section according to the foundation bearing capacity of the soil layer of the in-situ site where each barrier section is located and the preset depth of the barrier. The barrier often involves a strong permeable layer (sand, silt) when passing through the strata, and the barrier base needs to be embedded in a weak permeable layer (clay). Therefore, the soil particle seal within the construction range of the barrier is often complex. Since the mixing component operates in a vibration mode, a large amount of energy input is required (about 3 to 5 times that of the non-vibration mode). Therefore, it is necessary to find a balance between the homogeneous mixing of the barrier material and the energy consumption. According to the geological conditions, the present invention refines the vibration frequency of the mixing tool by quantitatively calculating the thickness of each stratum, so as to achieve homogeneous mixing of the barrier material and reduce construction energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a side view of a contaminated site barrier manufacturing device according to an embodiment of the present invention;

[0034] Figure 2 is a front view of a contaminated site barrier manufacturing device according to an embodiment of the present invention;

[0035] Figure 3 It is a point arrangement diagram for testing before manufacturing the barrier in a specific example of the present invention;

[0036] Figure 4 It is the actual soil layer distribution and theoretical soil layer distribution diagram of the locations of the two barrier sections in the specific example of the present invention.

[0037] In the figure: walking base 1, traction shaft 101, vibrating traction arm 2, motor 201, power shaft 202, limit guide rail 203, stirring assembly 3, stirring arm 301, stirring tool 302, power wheel 3021, guide wheel 3022, bracket 3023, chain 3024, stirring blade 30241, positioning and signal interactor 4, first discharge pipe 501, second discharge pipe 502, barrier barrier towards stratum 6, first soil layer 601, second soil layer 602, third soil layer 603, preset depth of barrier barrier 7, first test point 801, second test point 802, third test point 803. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is described in detail below.

[0039] The embodiment of the present invention provides a contaminated site barrier manufacturing device, such as Figure 1 and Figure 2As shown, it includes a walking base 1, a vibrating traction arm 2 and a stirring assembly 3, the vibrating traction arm 2 is connected to the walking base 1 through a rotating drive assembly, and the stirring assembly 3 is connected to the vibrating traction arm 2 through a vibrating drive assembly. The rotating drive assembly is used to drive the vibrating traction arm 2 to drive the stirring assembly 3 to rotate relative to the walking base 1. The vibrating drive assembly is used to drive the stirring assembly 3 to vibrate along the axial direction of the stirring assembly 3 relative to the vibrating traction arm 2. The positioning and signal interactor 4 is installed on the walking base 1. The contaminated site barrier manufacturing device of this embodiment also includes a first discharge pipe 501 and a second discharge pipe 502, and the first discharge pipe 501 and the second discharge pipe 502 are both fixed on the stirring assembly 3. The first discharge pipe 501 is used to convey gel material, and the second discharge pipe 502 is used to convey air.

[0040] In the above embodiment, the walking base 1 is provided with a walking mechanism and can walk on the ground. According to the position of the barrier barrier, the manufacturing device moves to the designated position through the walking mechanism. The walking base 1 occupies a small area. Before walking, the rotating drive assembly drives the vibrating traction arm 2 to drive the stirring assembly 3 to rotate, so that the stirring assembly 3 is in a horizontal state, so that the walking base 1 walks normally. When the walking base 1 stops walking and builds a barrier barrier in the formation soil, the rotating drive assembly drives the vibrating traction arm 2 to drive the stirring assembly 3 to rotate, so that the stirring assembly 3 is in a vertical state, and the bottom of the stirring assembly 3 is located in the formation soil.

[0041] The gel material is delivered into the stirred soil through the first discharge pipe, and the air is delivered into the stirred soil through the second discharge pipe, so that the isolation barrier is manufactured.

[0042] As a preferred example, Figure 2 As shown, the stirring assembly 3 includes a stirring arm 301 and a stirring tool 302, wherein the stirring arm 301 is mounted on the vibrating traction arm 2 through a vibration drive assembly, and the stirring tool 302 is mounted on the stirring arm 301. The stirring tool includes a power wheel 3021, a guide wheel 3022, a bracket 3023, a chain 3024, a stirring blade 30241 and a stirring drive member. The bracket 3023 is fixedly connected to the stirring arm 301. The power wheel 3021 and the guide wheel 3022 are respectively mounted at both ends of the bracket 3023, and the chain 3024 is sleeved on the power wheel 3021 and the guide wheel 3022. The stirring drive member is connected to the power wheel 3021 to drive the power wheel 3021 to rotate. A plurality of stirring blades 30241 are installed on the chain 3024 at intervals along one circle of the chain 3024.

[0043] When working, the stirring drive member is turned on, and the stirring drive member drives the power wheel 3021 to rotate, driving the chain 3024 and the guide wheel 3022 to rotate. In this way, the stirring blade 30241 fixedly connected to the chain 3024 also rotates accordingly. The stirring purpose is achieved through the action between the stirring blade 30241 and the soil. During the working process of the stirring blade 30241, a stable mud vortex is formed around the chain 3024, which promotes the uniform mixing of the cementitious material and the in-situ soil.

[0044] Preferably, the rotation drive assembly includes a rotation drive member and a traction shaft 101, and the vibrating traction arm 2 is connected to the walking base 1 through the traction shaft 101, and the traction shaft 101 is arranged horizontally. The rotation drive member is installed on the vibrating traction arm 2 or the walking base 1 and connected to the traction shaft 101. When working, the rotation drive member drives the vibrating traction arm 2 to rotate around the traction shaft 101.

[0045] Preferably, the vibration drive assembly includes two counter-rotating motors 201 and two power shafts 202. The two motors 201 are mounted on the vibration traction arm 2. One end of the two power shafts 202 is connected to the two motors 201 respectively, and the other end is connected to two elliptical limit holes provided on the stirring arm 301 of the stirring assembly 3. The vibration traction arm 2 is provided with a limit rail 203 arranged along the axial direction of the bracket, and the stirring arm 301 is slidably connected to the limit rail 203 through a roller. The two counter-rotating motors 201 respectively drive the two power shafts to move along the elliptical limit holes, thereby causing the stirring assembly to reciprocate along the axial direction of the bracket to form vibration.

[0046] The embodiment of the present invention also provides a method for finely manufacturing a contaminated site barrier, using the contaminated site barrier manufacturing device provided in the above embodiment. It includes:

[0047] Step 10, performing segmented manufacturing along the extending direction of the barrier according to the preset depth, preset thickness and preset length of the barrier.

[0048] Among them, manufacturing a single-stage barrier segment specifically includes:

[0049] Step 201, the walking base 1 moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier barrier to the end point of the single-stage barrier segment. During the movement, the stirring component 3 mixes the gel material with the in-situ soil to form a first-stage barrier segment.

[0050] Step 202, start the vibration drive assembly, so that the stirring assembly 3 vibrates along the axial direction of the stirring assembly 3 relative to the vibration traction arm 2. The walking base 1 moves from the end point of the single-stage barrier segment to the starting point of the single-stage barrier segment along the preset extension direction of the barrier. During the movement, the stirring assembly 3 mixes the air with the first-stage barrier segment, and increases the uniformity of the cementitious material and the in-situ soil through the enhanced disturbance and vibration of the air, so as to form the second-stage barrier segment.

[0051] Step 203, the walking base 1 moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier barrier to the end point of the single-stage barrier segment. During the movement, the stirring assembly 3 stirs the second-stage barrier segment to expel the gas in the barrier barrier to form a third-stage barrier segment, thereby completing the manufacture of the single-stage barrier segment.

[0052] As a preferred example, in step 202 and step 203, the vibration frequency of the stirring assembly 3 is set according to the in-situ geological conditions of the location where the single-stage barrier segment is located. In step 202, the moving speed of the walking base 1 is set according to the in-situ geological conditions of the location where the single-stage barrier segment is located.

[0053] Due to the colloidal properties of the gelling material in the barrier, it gradually transforms from a network colloid to a suspension under vibration conditions, and then transforms from a suspension to a network colloid after the vibration stops. In order to achieve the third stage of being able to efficiently expel the bubbles in the gel material and the in-situ soil, the present invention optimizes the moving speed of the walking base in the second stage, and the time between the end point of the single-stage barrier section being mixed in the second stage and being mixed in the third stage, that is, the total time for the walking base to move from the end point to the starting point in the second stage, and from the starting point to the end point in the third stage, is greater than the time for the colloidal material in the barrier at the end point to be transformed from a suspension to a network colloid. By optimizing the moving speed of the walking base, the present invention can reduce the energy consumption of the construction process and improve the mixing uniformity of the barrier material.

[0054] Preferably, the vibration frequency of the stirring assembly 3 is set according to the in-situ geological conditions of the location of the single-stage barrier segment, specifically including:

[0055] Step 211, detect and obtain the foundation bearing capacity of the starting point and the end point of the single-segment barrier section. The stratum bearing capacity is the cone tip resistance, the side wall resistance or the total penetration resistance. According to the foundation bearing capacity of the starting point and the end point, the strata are divided, and there are n soil layers in total. According to the foundation bearing capacity of the starting point, the top surface depth and the bottom surface depth of each soil layer at the starting point are obtained. According to the foundation bearing capacity of the end point, the top surface depth and the bottom surface depth of each soil layer at the end point are obtained. Among them, the preset depth of the blocking barrier is used as the bottom surface depth of the soil layer where the bottom end of the blocking barrier at the starting point and the end point is located. For example, the preset depth of the blocking barrier is 7m, and the bottom surface depth of the second soil layer from top to bottom at the starting point (that is, the top surface depth of the third soil layer) is 6.05m, and the bottom surface depth of the third soil layer is greater than 7m, that is, the bottom end of the blocking barrier is located in the third soil layer, and 7m is used as the bottom surface depth of the third soil layer at the starting point.

[0056] Step 212: According to the top surface depth and bottom surface depth of each soil layer at the starting point, the thickness of each soil layer at the end point is obtained by subtracting the top surface depth from the bottom surface depth. According to the top surface depth and bottom surface depth of each soil layer at the end point, the thickness of each soil layer at the end point is obtained by subtracting the top surface depth from the bottom surface depth. The average thickness of each soil layer between the starting point and the end point is calculated. represents the average thickness of the jth soil layer between the starting point and the end point of the i-th barrier segment, represents the thickness of the jth soil layer at the starting point of the i-th barrier segment, Represents the thickness of the jth soil layer at the end point of the i-th barrier segment.

[0057] Step 213, according to the top surface depth and bottom surface depth of each soil layer at the starting point, the midline depth of each soil layer at the end point is obtained. According to the top surface depth and bottom surface depth of each soil layer at the end point, the midline depth of each soil layer at the end point is obtained. According to the foundation bearing capacity of the midline depth of each soil layer at the starting point and the midline depth of each soil layer at the end point, the foundation bearing capacity of the midline depth of each soil layer at the starting point and the midline depth of each soil layer at the end point is obtained. The average foundation bearing capacity of each soil layer between the starting point and the end point is calculated. represents the average foundation bearing capacity of the jth soil layer between the starting point and the end point of the i-th barrier segment, represents the bearing capacity of the foundation at the midline depth of the jth soil layer at the starting point of the i-th barrier segment, Represents the foundation bearing capacity at the midline depth of the jth soil layer at the end point of the i-th barrier segment.

[0058] Step 214, using formula (1) to calculate the vibration frequency of the stirring assembly when manufacturing a single-stage barrier segment:

[0059] Formula (1)

[0060] In the formula, It represents the vibration frequency of the stirring assembly when manufacturing the i-th barrier segment, in Hz; It represents the average thickness of the first soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the first soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the second soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the second soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the nth soil layer between the starting point and the end point of the i-th barrier segment, in meters; It represents the average foundation bearing capacity of the nth soil layer between the starting point and the end point of the i-th barrier segment, in MPa; Indicates the preset depth of the barrier; Indicates the first preset coefficient, in Hz; Indicates the second preset coefficient, in Hz·MPa -1 ; represents the total number of barrier segments, and n represents the total number of soil layers. Preferably, The value range is 30 to 60. The value range is 8 to 12.

[0061] Since the barrier is a linear structure that spans a long distance, the strata along the line will change, especially for complex strata formed by impact along rivers and streams. The number of soil layers traversed within the preset depth of the barrier, the thickness of each layer, the properties of the soil, etc. will affect the homogeneity and service performance of the barrier. For example, if there is only sand in the stratum to be traversed, after the cementitious material and the sand are mixed, the agglomeration of the two is weak, so it is less difficult to achieve uniform mixing, which can be completed under the low-frequency vibration conditions of the mixing component; however, when there is a large amount of fine-grained clay (silt and clay) in the stratum to be traversed, the cementitious material and the clay particles are cemented to form agglomerates. At this time, it is difficult to achieve effective mixing of sand and agglomerates. Therefore, it is necessary to provide more kinetic energy for the sand particles under high-frequency vibration conditions so that they can enter the agglomerates and form a stable network-like colloid-sand core structure. According to the geological conditions, the embodiment of the present invention refines the vibration frequency of the mixing component by quantitatively calculating the thickness of each stratum, so as to achieve homogeneous mixing of the barrier material and reduce construction energy consumption.

[0062] Preferably, according to the in-situ geological conditions of the location of the barrier, the moving speed of the walking base is calculated using formula (2):

[0063] Formula (2)

[0064] In the formula, represents the moving speed of the walking base in step 202 when manufacturing the i-th barrier segment, in m / min; Indicates the third preset coefficient, in m / min; Indicates the fourth preset coefficient, the unit is m·min -1 MPa -1 Preferably, The value range is 1.8~2.2, The value range is 0.08~0.12.

[0065] Preferably, in step 201, the moving speed of the walking base is 1.0 m / min. In step 203, the moving speed of the walking base is 2.0 m / min.

[0066] A specific example is provided below.

[0067] The soil and groundwater of a contaminated site are contaminated. In order to control the migration of pollutants in the soil and groundwater of the site to the downstream direction of the groundwater flow, a barrier is built at the boundary of the site. After preliminary design, the barrier is 7.0 m deep, 0.8 m thick, and 60 m long. The barrier is designed and constructed in sections of 30 m, and a total of two barrier sections are built.

[0068] Before entering the site to manufacture the barrier, a geological survey is first carried out. The bearing capacity parameters of the strata within the preset depth at the starting point and end point of each barrier section are tested. Three in-situ test points are arranged along the extension direction of the barrier, such as Figure 3 As shown, they are the first test point 801, the second test point 802 and the third test point 803. The first test point is the starting point of the first barrier section, the second test point 802 is the end point of the first barrier section and the starting point of the second barrier section, and the third test point 803 is the end point of the second barrier section. In this example, the cone tip resistance obtained by the in-situ double-bridge probe test is used as the foundation bearing capacity. According to the foundation bearing capacity obtained by the test, it is obtained that within a depth of 7.0m, it spans three geological layers from top to bottom, namely the first soil layer 601, the second soil layer 602 and the third soil layer 603, as shown in Figure 4 shown.

[0069] Manufacturing parameter design of the first barrier section:

[0070] The thicknesses of the three soil layers at the starting point of the first barrier section are obtained, as shown in Table 1.

[0071] Table 1 Soil parameters at the starting point of the first barrier section

[0072]

[0073] The thicknesses of the three soil layers at the end point of the first barrier section are shown in Table 2.

[0074] Table 2 Soil parameters at the end of the first barrier section

[0075]

[0076] Calculation shows that the average thickness of the three soil layers from top to bottom in the first barrier section are 1.81m, 3.87m, and 1.33m.

[0077] The cone tip resistance of the midline depth of the three soil layers between the starting point and the end point of the first barrier section was detected, and the average cone tip resistance of each soil layer between the starting point and the end point of the first barrier section was calculated, as shown in Table 3. In this specific example, since the preset depth of the barrier is 7m, only a part of the barrier within the depth range (minimum immersion depth 0.95m, maximum embedding depth 1.70m) is embedded in the third soil layer, so the cone tip resistance of the barrier embedded in the 1 / 2 depth of the third soil layer (i.e., 0.48m below the top surface of the third soil layer at the starting point and 0.85m below the top surface of the third soil layer at the end point) is used as the cone tip resistance of the midline depth of the layer.

[0078] Table 3 Cone tip resistance of the first barrier section

[0079]

[0080] The vibration frequency of the stirring assembly when manufacturing the first barrier segment is calculated using formula (1), where: a =50Hz, b =10 Hz MPa -1 , the vibration frequency of the stirring assembly in the second and third stages when manufacturing the first barrier segment is 110.4 Hz, and the value is rounded down to an integer multiple of 5, and the vibration frequency is 110 Hz.

[0081] The moving speed of the walking base in the second stage when manufacturing the first barrier segment is calculated using formula (2). In formula (2), c =2.00 m / min, d =0.10 Hz MPa -1 The moving speed of the walking base when manufacturing the first barrier segment is 1.40 m / min.

[0082] In order to compare the effects of the vibration of the stirring assembly and the introduction of compressed air during the stirring process on the pollution interception effect of the constructed barrier, the first barrier section was divided into 5 subsections for construction, each of which was 6 m long. The construction parameters of the 5 subsections are shown in Table 4. In Table 4, vibration means that the stirring assembly is in vibration mode, and the vibration frequency is 110 Hz. The other construction parameters of the 5 subsections are the same.

[0083] Table 4 Construction process of the five sub-sections

[0084]

[0085] The steps for manufacturing the first sub-section of the first barrier section are as follows:

[0086] Step (1) The walking base 1 moves to the starting point of the first sub-section and keeps the axis of the manufacturing device consistent with the extension direction of the barrier.

[0087] Step (2) turns on the stirring drive of the stirring assembly 3, so that the chain 3024 drives the stirring blade 30241 to rotate, and the rotation speed is controlled at 2.5 rad / min.

[0088] Step (3) The walking base 1 remains stationary, and the rotation drive assembly is turned on to drive the vibrating traction arm 2 and the stirring assembly 3 to rotate around the traction shaft 101. The rotation speed is appropriately adjusted according to the soil quality of the stratum until the stirring tool 302 is in a vertical state.

[0089] Step (4) The cement-based cementitious material is sprayed out through the first discharge pipe 501 and contacts with the in-situ soil. Under the action of the stirring component 3, the cementitious material and the in-situ soil are mixed. At this time, the stirring component 3 is in a static working state (non-vibrating working state). The walking base 1 travels along the extension direction of the barrier at a speed of 1.0 m / min. After traveling to the end point of the first sub-segment, the cementitious material is stopped from being sprayed. At this point, the first stage barrier section of the first sub-segment is completed.

[0090] Step (5) The walking base 1 remains stationary, and the rotation drive assembly is turned on to drive the vibrating traction arm 2 and the stirring assembly 3 to rotate around the traction shaft 101, so that the stirring tool 302 is in an inclined state, and the angle between it and the vertical plane is 15°.

[0091] Step (6) turns on the vibration drive assembly with a vibration frequency of 110 Hz, and drives the stirring assembly to vibrate along the axis of the stirring assembly relative to the vibration traction arm. Compressed air is ejected through the second discharge pipe 502 and contacts the first-stage barrier segment. The walking base 1 travels along the extension direction of the barrier at a speed of 1.40 m / min, returning from the end point of the first sub-segment to the starting point of the first sub-segment. After reaching the starting point of the first sub-segment, stop ejecting compressed air. At this point, the second-stage barrier segment of the first sub-segment is completed.

[0092] Step (7) The walking base 1 remains stationary, and the rotation drive assembly is turned on to drive the vibrating traction arm 2 and the stirring assembly 3 to rotate around the axis of the traction shaft 101, so that the stirring tool 302 is in an inclined state, and the angle between it and the vertical plane is 30°.

[0093] Step (8) The walking base 1 moves along the extending direction of the barrier at a speed of 2.0 m / min from the starting point of the first sub-segment to the end point of the first sub-segment, and the stirring drive of the stirring assembly 3 is turned off. At this point, the first sub-segment is completed.

[0094] According to the construction process in Table 4, repeat steps (1) to (8) to construct the remaining fields, thereby completing the construction of the first barrier segment.

[0095] After 28 days of curing, samples were collected at depths of 1.0m, 3.0m, and 6.0m in the middle of each subsection, and the permeability coefficient of the samples was tested in accordance with the Standard for Geotechnical Test Methods (GB / T 50123-2019). The average values ​​of the three test values ​​of samples at different depths were taken. The average permeability coefficients of the five subsections were 2.15×10 -7 cm / s、6.50×10 -6 cm / s、7.03×10 -7 cm / s, 2.37×10 -7 cm / s、2.91×10 -7 cm / s.

[0096] By comparing the first, second and third subsections, it can be found that the vibration process in the second and third stages can significantly increase the mixing efficiency and reduce the permeability coefficient of the barrier. By comparing the first, fourth and fifth subsections, it can be found that the vibration and gas injection process in the first stage not only did not reduce the permeability coefficient of the barrier, but also slightly increased the permeability coefficient of the barrier after vibration and gas injection in the first stage, indicating that it is not suitable to start vibration and gas injection in the first stage. Due to the migration of the contaminated area caused by the vibration and gas injection process in the first stage, the groundwater pollution concentration at the construction location of the barrier increased, which inhibited the hydration process of the cementitious material and led to an increase in the permeability coefficient.

[0097] Manufacturing parameter design of the second barrier segment:

[0098] The thicknesses of the three soil layers at the starting point of the second barrier section are obtained, as shown in Table 5.

[0099] Table 5 Soil parameters at the starting point of the second barrier section

[0100]

[0101] The thicknesses of the three soil layers at the end point of the second barrier section are shown in Table 6.

[0102] Table 6 Soil parameters at the end of the second barrier section

[0103]

[0104] Calculation shows that the average thickness of the three soil layers from top to bottom in the second barrier section are 2.59m, 1.99m, and 2.43m.

[0105] The cone tip resistance of the midline depth of the three soil layers between the starting point and the end point of the second barrier section was detected, and the average cone tip resistance of each soil layer between the starting point and the end point of the second barrier section was calculated, as shown in Table 7. In this specific example, since the preset depth of the barrier is 7m, only a part of the barrier within the depth range (minimum immersion depth 1.70m, maximum embedding depth 3.15m) is embedded in the third soil layer, so the cone tip resistance of the barrier embedded in the 1 / 2 depth of the third soil layer (i.e. 0.85m below the top surface of the third soil layer at the starting point and 1.58m below the top surface of the third soil layer at the end point) is used as the cone tip resistance of the midline depth of the layer.

[0106] Table 7 Cone tip resistance of the second barrier section

[0107]

[0108] The vibration frequency of the stirring assembly when manufacturing the second barrier segment is calculated using formula (1), where: a =50Hz, b =10Hz·MPa -1 , the vibration frequency of the second and third stage stirring components when manufacturing the second barrier segment is 99 Hz, and the value is taken as an integer multiple of 5, and the vibration frequency is 95 Hz.

[0109] The moving speed of the walking base when manufacturing the second barrier segment is calculated using formula (2). In formula (2), c =2.00m / min, d =0.10Hz·MPa-1 The moving speed of the second-stage walking base when manufacturing the second barrier segment is 1.51 m / min.

[0110] In order to compare the effects of the vibration frequency of the stirring assembly and the moving speed of the walking base on the pollution interception effect of the constructed barrier, the second barrier section was divided into 5 subsections for construction, each with a length of 6m. The construction parameters of the 5 subsections are shown in Table 8. The other construction parameters of the 5 subsections are the same.

[0111] Table 8 Construction process of the five subsections

[0112]

[0113] According to the construction process shown in Table 8, steps (1) to (8) are repeated to construct five sub-segments, thereby completing the construction of the second barrier segment.

[0114] After 28 days of curing, samples were collected at depths of 1.0m, 3.0m, and 6.0m in the middle of each subsection to test the permeability coefficient of the samples. The average values ​​of the three test values ​​of samples at different depths were taken. The average permeability coefficients of the barriers in the five subsections were 2.32×10 -7 cm / s、1.53×10 -6 cm / s, 2.35×10 -7 cm / s、2.27×10 -7 cm / s、8.11×10 -7 cm / s.

[0115] Comparing the first, second and third sub-paragraphs, it can be found that when the vibration frequency is lower than 95 Hz, the permeability coefficient of the barrier increases (second sub-paragraph), while when the vibration frequency is greater than 95 Hz, the permeability coefficient of the barrier remains basically unchanged (third sub-paragraph). Comparing the first, fourth and fifth sub-paragraphs, it can be found that when the moving speed of the walking base is lower than 1.51 m / min, the permeability coefficient of the barrier remains basically unchanged (fourth sub-paragraph), while when the vibration frequency is greater than 95 Hz, the permeability coefficient of the barrier increases significantly (fifth sub-paragraph).

[0116] It can be concluded that the method of the present invention uses formulas (1) and (2) to calculate the vibration frequency of the stirring assembly and the moving speed of the walking base, which can ensure that the permeability coefficient of the barrier is minimized and reduce construction energy consumption.

[0117] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above specific embodiments, and the descriptions in the above specific embodiments and the specification are only for further illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed for protection.

Claims

1. A refined manufacturing method for a contaminated site barrier, characterized in that: A contaminated site barrier manufacturing device is used, the contaminated site barrier manufacturing device comprising a walking base (1), a vibrating traction arm (2) and a stirring assembly (3), the vibrating traction arm (2) being connected to the walking base (1) via a rotating drive assembly, and the stirring assembly (3) being connected to the vibrating traction arm (2) via a vibrating drive assembly; the vibrating traction arm (2) can drive the stirring assembly (3) to rotate relative to the walking base (1), and the stirring assembly (3) can vibrate relative to the vibrating traction arm (2) along the axial direction of the stirring assembly (3); The method comprises: Step 10, performing segmented manufacturing along a preset extension direction of the barrier according to a preset depth, a preset thickness and a preset length of the barrier; Among them, manufacturing a single-stage barrier segment specifically includes: Step 201, the walking base (1) moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier segment to the end point of the single-stage barrier segment; during the movement, the stirring component (3) mixes the gel material with the in-situ soil to form a first-stage barrier segment; Step 202, start the vibration drive assembly, so that the stirring assembly (3) vibrates relative to the vibration traction arm (2) along the axial direction of the stirring assembly (3); the walking base (1) moves from the end point of the single-stage barrier segment along the preset extension direction of the barrier segment to the starting point of the single-stage barrier segment; during the movement, the stirring assembly (3) mixes air with the first-stage barrier segment to form a second-stage barrier segment; Step 203, the walking base (1) moves from the starting point of the single-stage barrier segment along the preset extension direction of the barrier barrier to the end point of the single-stage barrier segment; during the movement, the stirring component (3) stirs the second-stage barrier segment to form a third-stage barrier segment; and the manufacture of the single-stage barrier segment is completed.

2. The refined manufacturing method of the contaminated site barrier according to claim 1 is characterized in that: In step 202 and step 203, the vibration frequency of the stirring assembly (3) is set according to the in-situ geological conditions at the location of the single-stage barrier segment; in step 202, the moving speed of the walking base (1) is set according to the in-situ geological conditions at the location of the single-stage barrier segment.

3. The refined manufacturing method of the contaminated site barrier according to claim 2 is characterized in that: According to the in-situ geological conditions of the location of the single-stage barrier section, the vibration frequency of the stirring assembly (3) is set, specifically including: Step 211, detecting and obtaining the foundation bearing capacity of the starting point and the end point of the single-segment barrier segment; obtaining the top surface depth and the bottom surface depth of each soil layer at the starting point according to the foundation bearing capacity of the starting point; obtaining the top surface depth and the bottom surface depth of each soil layer at the end point according to the foundation bearing capacity of the end point; wherein the preset depth of the barrier is used as the bottom surface depth of the soil layer where the bottom end of the barrier at the starting point and the end point is located; Step 212, obtaining the thickness of each soil layer at the starting point according to the top surface depth and the bottom surface depth of each soil layer at the starting point; obtaining the thickness of each soil layer at the end point according to the top surface depth and the bottom surface depth of each soil layer at the end point; obtaining the average thickness of each soil layer between the starting point and the end point according to the thickness of each soil layer at the starting point and the thickness of each soil layer at the end point; Step 213, obtaining the centerline depth of each soil layer at the starting point according to the top surface depth and the bottom surface depth of each soil layer at the starting point; obtaining the centerline depth of each soil layer at the end point according to the top surface depth and the bottom surface depth of each soil layer at the end point; obtaining the average foundation bearing capacity of each soil layer between the starting point and the end point according to the foundation bearing capacity of the centerline depth of each soil layer at the starting point and the centerline depth of each soil layer at the end point; Step 214, using formula (1) to calculate the vibration frequency of the stirring assembly when manufacturing a single-stage barrier: Formula (1) In the formula, It represents the vibration frequency of the stirring assembly when manufacturing the i-th barrier segment, in Hz; It represents the average thickness of the first soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the first soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the second soil layer between the starting point and the end point of the i-th barrier segment, in m; It represents the average foundation bearing capacity of the second soil layer between the starting point and the end point of the i-th barrier segment, in MPa; It represents the average thickness of the nth soil layer between the starting point and the end point of the i-th barrier segment, in meters; It represents the average foundation bearing capacity of the nth soil layer between the starting point and the end point of the i-th barrier segment, in MPa; Indicates the preset depth of the barrier; Indicates the first preset coefficient, in Hz, The value range of is 30~60; Indicates the second preset coefficient, in Hz·MPa -1 , The value range of is 8 to 12; represents the total number of barrier segments, and n represents the total number of soil layers.

4. The refined manufacturing method of the contaminated site barrier according to claim 3 is characterized in that: According to the in-situ geological conditions of the location of the barrier, the moving speed of the walking base is calculated using formula (2): Formula (2) In the formula, represents the moving speed of the walking base in step 202 when manufacturing the i-th barrier segment, in m / min; Indicates the third preset coefficient, in m / min. The value range of is 1.8~2.2; Indicates the fourth preset coefficient, the unit is m·min -1 MPa -1 , The value range is 0.08~0.

12.

5. The refined manufacturing method of the contaminated site barrier according to claim 1 is characterized in that: In step 201, the moving speed of the walking base is 1.0 m / min; in step 203, the moving speed of the walking base is 2.0 m / min.

6. The refined manufacturing method of the contaminated site barrier according to claim 1 is characterized in that: The stirring assembly (3) comprises a stirring arm (301) and a stirring tool (302); the stirring arm (301) is mounted on a vibrating traction arm (2) via a vibration drive assembly, and the stirring tool (302) is mounted on the stirring arm (301); the stirring tool comprises a power wheel (3021), a guide wheel (3022), a bracket (3023), a chain (3024), a stirring blade (30241) and a stirring drive member; the bracket (3023) and the stirring arm (301) are fixedly connected; the power wheel (3021) and the guide wheel (3022) are respectively mounted on two ends of the bracket (3023), and the chain (3024) is sleeved on the power wheel (3021) and the guide wheel (3022); the stirring drive member is connected to the power wheel (3021) and is used to drive the power wheel (3021) to rotate; and the stirring blade (30241) is fixedly connected to the chain (3024).

7. The refined manufacturing method of the contaminated site barrier according to claim 1 is characterized in that: The stirring assembly (3) is slidably connected to the vibrating traction arm (2); the vibrating drive assembly comprises two motors (201) rotating in opposite directions and two power shafts (202); the two motors (201) are mounted on the vibrating traction arm (2); one end of the two power shafts (202) is respectively connected to the two motors (201), and the other end is respectively connected to two elliptical limiting holes on the stirring assembly (3).

8. The refined manufacturing method of the contaminated site barrier according to claim 1 is characterized in that: The contaminated site barrier manufacturing device further comprises a first discharge pipe (501) and a second discharge pipe (502), wherein the first discharge pipe (501) and the second discharge pipe (502) are fixed on the stirring assembly (3).

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