Coral sand foundation reinforcing device and method based on biological grouting

Abstract

The invention provides a coral sand foundation reinforcing device and method based on biological grouting, the coral sand foundation reinforcing device comprises normal pipelines and horizontal pipelines, the coral sand foundation reinforcing device is laid on a coral sand foundation, and every two adjacent layers of horizontal pipelines are communicated through the corresponding normal pipeline; the horizontal pipeline is provided with a through hole, and the interior of the through hole is blocked through low-melting-point alloy. A conductive assembly is arranged on the pipe wall of the horizontal pipeline and electrically connected with the low-melting-point alloy, and after the low-melting-point alloy is electrified and melted, slurry in the pipeline system flows out of the through hole and is solidified. The characteristics of layered dynamic compaction construction of the ocean island coral sand foundation are combined, dynamic compaction energy in the reinforcing process is utilized, the compaction energy is converted into electric energy, the hot melting process of low-melting-point alloy after pipeline burying is completed is achieved, dependence on an external power source in the ocean island construction process is reduced, and the construction efficiency is improved. And the pipeline system can be used as a reinforcing structure to form a three-dimensional reinforcing body, so that the bearing capacity of the coral sand foundation is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of marine engineering foundation reinforcement, and relates to a coral sand foundation reinforcement device and reinforcement method based on biological grouting. Background Art

[0002] Layered filling is a commonly used construction method for coral sand island and reef foundations. As a typical marine sediment, coral sand has complex particle morphology, poor gradation, and poor cementation. The coral sand foundation formed by filling has defects such as high porosity, low compression modulus, and low bearing capacity, so the coral sand foundation needs to be reinforced. However, for offshore coral sand islands and reefs, there are problems such as high transportation costs of large machinery and difficulty in maintaining a stable power supply before they are built. Therefore, current conventional foundation treatment methods are difficult to implement, have low implementation efficiency, and the treatment effect is less than ideal. Therefore, there is an urgent need to propose an environmentally friendly, efficient, economical, and adaptable coral sand foundation reinforcement treatment method.

[0003] The main principle of the biologically induced carbonate precipitation reinforcement method is that urease catalyzes the hydrolysis of urea to produce carbonate ions, which form calcium carbonate cement in the coral sand with the calcium ions in the reinforcement slurry, filling the pores between the coral sand particles, enhancing the adhesion and strength of the soil particles, and improving the stability of the foundation. However, the existing technical means for treating coral sand foundations usually involve building vertical reinforcement grouting pipelines through secondary construction after the coral sand filling is completed, and injecting reinforcement slurry into the coral sand foundation, which does not effectively take into account the construction characteristics of layered filling of island and reef foundations; at the same time, the reinforcement grouting pipelines laid out after the reinforcement is completed are usually buried at a very limited depth, and do not serve as a permanent reinforcement structure for the coral sand foundation, and it is difficult to effectively improve the overall stability of the deep coral sand foundation formed by multiple layered filling; in this context, due to the limitations of the current grouting pipeline layout, the current microbial grouting liquid has a two-dimensional diffusion characteristic in the form of points and lines, which often leads to problems such as uneven distribution of reinforcement slurry, limited reinforcement range, blockage of reinforcement grouting pipelines, and unstable reinforcement effect. It is difficult to form a three-dimensional site-scale reinforcement body, and thus it is impossible to achieve an overall improvement in the bearing capacity of the coral sand foundation.

[0004] In summary, combined with the characteristics of coral sand foundation blown fill layered construction, the present invention proposes a coral sand foundation reinforcement device and reinforcement method based on bio-grouting, which realizes multi-dimensional reinforcement of blown fill coral sand foundation and has practical engineering value. Summary of the Invention

[0005] To overcome the problems of the existing technology, the present invention provides a coral sand foundation reinforcement device and method based on bio-grouting. This method is suitable for the construction of new coral sand island and reef foundations. Through a two-stage collaborative reinforcement mechanism of reinforcing reinforcement implants and microbial grouting, multi-dimensional reinforcement is achieved. A real-time monitoring system is used to regulate the grouting process, ensuring the long-term and stable reinforcement of the coral sand foundation. While adhering to the principles of environmental protection, the technical solution of the present invention achieves a significant increase in the foundation's bearing capacity, providing a solid foundation for the construction of new island and reef infrastructure.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a coral sand foundation reinforcement device based on biological grouting, comprising a pipeline system for grouting; the pipeline system comprises normal pipelines and horizontal pipelines; the horizontal pipelines are arranged in several layers and laid on the coral sand foundation, and two adjacent horizontal pipeline layers are connected via the normal pipeline, and the top opening of the normal pipeline can be passed into the biological slurry, and the biological slurry enters the horizontal pipeline through the normal pipeline; the horizontal pipeline is provided with several through holes, and the through holes are blocked by a low-melting-point alloy; the pipe wall of the horizontal pipeline is provided with a conductive component, and the conductive component is electrically connected to the low-melting-point alloy. When the low-melting-point alloy is energized and melted, the biological slurry in the horizontal pipeline flows out from the through holes and solidifies in the coral sand.

[0008] Furthermore, the conductive component includes a power generation element and a conductive wire; the power generation element includes an upper copper film, a lower copper film and a plurality of polytetrafluoroethylene dielectric balls, the upper copper film and the lower copper film are arranged inside the pipe wall of the horizontal pipeline, and the polytetrafluoroethylene dielectric balls are movably arranged between the upper copper film and the lower copper film; the upper copper film and the lower copper film are respectively connected to the low-melting-point alloy through conductive wires; when the coral sand layer above the horizontal pipeline is rammed, the horizontal pipeline vibrates or deforms accordingly, and the polytetrafluoroethylene dielectric balls can collide and rub with the upper copper film / lower copper film to generate current, and the generated current is discharged through the wires on the upper copper film / lower copper film to form a current loop, thereby converting the ramming energy into electrical energy.

[0009] Furthermore, the horizontal pipeline is also provided with an epoxy glass fiber outer shell and a reinforced inner shell; the power generation component is arranged between the epoxy glass fiber outer shell and the reinforced inner shell, the upper copper film is attached to the inner wall of the epoxy glass fiber outer shell, and the lower copper film is attached to the inner wall of the reinforced inner shell; the reinforced inner shell includes a silicone tube wall and a carbon fiber mesh tube, and the carbon fiber mesh tube is embedded and laid in the silicone tube wall.

[0010] Furthermore, the horizontal pipeline is also provided with a flap structure having the same number as the through holes; the flap structure is arranged inside the through hole, one side of the flap structure is fixedly connected to the epoxy glass fiber outer shell and the reinforced inner shell, and the other side is in contact with the low melting point alloy.

[0011] Furthermore, the cross-sectional area of ​​the through hole gradually decreases from the inside to the outside.

[0012] Furthermore, the horizontal pipeline includes several horizontal grouting pipes, and two adjacent horizontal grouting pipes are connected through a first connecting piece; the first connecting piece includes a U-shaped tube or a straight tube, and the connecting end of the U-shaped tube / straight tube is provided with a first clamping plate, and a first clamping slot is provided on the first clamping plate. The horizontal grouting pipe is provided with a first buckle, and when the first connecting piece is connected to the horizontal grouting pipe, the first buckle is clamped in the first clamping slot.

[0013] Furthermore, the horizontal pipeline and the normal pipeline are connected through a second connecting piece; the second connecting piece includes a hollow shell, and the hollow shell is provided with a horizontal connecting end and a vertical connecting end respectively adapted to the horizontal pipeline and the normal pipeline; the horizontal connecting end and the vertical connecting end are respectively provided with a second clamping plate, and a second clamping slot is provided on the second clamping plate, and the horizontal pipeline and the normal pipeline are respectively provided with a second clip. When the horizontal pipeline and the normal pipeline are connected to the horizontal connecting end and the vertical connecting end respectively, the second clip is clamped in the second clip slot.

[0014] Furthermore, a monitoring system is provided at the end of the horizontal pipeline; the monitoring system includes a pH sensor head, a signal transmitter and a power supply element; the power supply element is used to power the pH sensor head and the signal transmitter, and the pH sensor head is used to detect the pH of the grouting area and send it to the main control system through the signal transmitter.

[0015] (2) The present invention also provides an application method of the above-mentioned coral sand foundation reinforcement device based on bio-grouting, comprising the following steps:

[0016] S1. Pre-fill a layer of coral sand on the coral sand foundation;

[0017] S2. Lay the first-layer horizontal pipeline on the surface of the blown-in coral sand formation, connect the first-layer normal pipeline to the connection end of the first-layer horizontal pipeline, and seal the normal pipeline. Then, blow-fill the coral sand above the first-layer horizontal pipeline. After the blow-fill is completed, perform a dynamic compaction operation until the low-melting-point alloy in the first-layer horizontal pipeline is completely melted.

[0018] S3. Unblock the normal pipeline and lay the second layer of horizontal pipeline on the surface of the compacted layer. Connect the lower connecting end of the second layer of horizontal pipeline to the normal pipeline of the first layer, and connect the upper connecting end to the normal pipeline of the second layer. Block the second layer of normal pipeline. Then, blow-fill coral sand above the second layer of normal pipeline. After the blow-fill is completed, perform a dynamic compaction operation until the low-melting-point alloy in the second layer of horizontal pipeline is completely melted.

[0019] S4. Repeat step S3 until the design height is reached and all horizontal pipelines are laid;

[0020] S5. Grouting is performed through the normal pipeline of the top layer into the horizontal pipelines of each layer. The slurry is injected into the coral sand layer through the through holes, causing a mineralization reaction to solidify the coral sand layers, thus completing the coral sand foundation reinforcement.

[0021] Furthermore, in steps S2 and S3, the dynamic compaction operation is specifically as follows: tamping the coral sand layer above the horizontal pipeline; during tamping, the horizontal pipeline vibrates or deforms, and the polytetrafluoroethylene dielectric ball collides and rubs with the upper copper film / lower copper film to generate current, which is conducted through the wires on the upper copper film / lower copper film to form a current loop, converting the tamping energy into electrical energy to melt the low-melting-point alloy of the horizontal pipeline.

[0022] Furthermore, the slurry is a premixed solution of urea-hydrolyzing microorganisms and a urea-calcium source. This premixed solution has a low pH property. During grouting, the premixed solution is injected into the piping system and flows out of the through-holes of the piping system to reinforce the coral sand layer. Alternatively, the slurry is divided into a urea-hydrolyzing microorganism culture solution and a urea-calcium source solution. During grouting, the urea-hydrolyzing microorganism culture solution is first injected, and then allowed to stand for a period of time to allow the microorganisms to adhere to the coral sand layer. Then, the urea-calcium source solution is injected in batches to initiate the curing reaction.

[0023] The present invention utilizes the construction characteristics of the coral sand foundation's layered filling to carry out a two-stage collaborative reinforcement of the coral sand foundation, which involves implanting reinforcements and microbial grouting reinforcement. The first reinforcement stage is the reinforcement implantation stage. Utilizing the characteristics of the island and reef filling process, the horizontal pipeline system is laid out layer by layer and assembled through the normal pipeline system to form a multi-layer assembled pipeline system. The pipeline systems in each region are connected through connectors. The impact energy generated during the strong compaction stage of the filling process is converted and utilized to generate electrical energy to melt the preset positions in the pipeline system. The second reinforcement stage, bio-grouting reinforcement, is carried out using the reinforced body structure of the first reinforcement stage as a carrier for transporting the reinforcing slurry. The bio-grouting reinforcement performs layered reinforcement on the coral sand foundation, forming calcium carbonate precipitation to fill the pores between the coral sand particles, thereby improving the density and bearing capacity of the coral sand foundation. The two-stage synergistic effect forms a multi-dimensional three-dimensional reinforcement body.

[0024] The beneficial effects of the present invention are:

[0025] (1) The present invention makes full use of the process flow of layered filling of coral sand foundation to carry out two-stage coordinated reinforcement of coral sand foundation. Different from the traditional biological grouting reinforcement method or reinforcement structure, the present invention combines the reinforcement structure and the biological reinforcement grouting pipeline into one, organically combining the two types of reinforcement methods, so that the bearing capacity of the coral sand foundation is further improved. After the filling work of each layer of coral sand foundation is completed, the horizontal and normal reinforcement grouting pipelines are arranged to finally form a three-dimensional structure, completing the first stage reinforcement of the coral sand foundation soil. During this period, the impact energy of the strong compaction process is converted by means of friction nanogenerators to melt low-melting-point alloys, and the reinforcement grouting pipelines are arranged in a flower-shaped manner, which is convenient for the subsequent grouting process. After the layout of all pipeline systems is completed, the reinforcement pipelines arranged in the previous stage are used as the reinforcement slurry transport carrier to inject the reinforcement slurry and carry out the second stage of biological reinforcement of the coral sand foundation, finally forming a three-dimensional reinforcement structure. Unlike traditional reinforcement piping systems, this structure can be used as a permanent structure after the bio-grouting process is complete, allowing for further treatment of the coral sand foundation as needed. This ultimately creates a three-dimensional composite reinforcement system that synergizes reinforcement with bio-grouting. This approach effectively reduces the existing reinforcement method's dependence on a stable power source, significantly reducing construction costs and leveraging the layer-by-layer construction characteristics of the blown-fill process. Furthermore, the reinforced structure utilizes an assembled construction process, offering the advantage of convenient construction.

[0026] (2) The pipeline system of the present invention ensures the smooth vertical injection of the bioreinforcement slurry while ensuring the flexible deformation of the horizontal pipeline system according to the actual layout position and usage requirements, thereby avoiding the possible blockage of the pipeline system. The friction nanogenerator technology is used on the outside of the pipeline system to convert the impact energy during the tamping process. The outer shell of the pipeline system is made of epoxy glass fiber material, which has the advantages of corrosion resistance, impact resistance and high temperature resistance. A polytetrafluoroethylene dielectric ball is placed inside the epoxy glass fiber shell, and the inner wall of the shell is covered with a copper film, and the reinforced inner shell is also covered with a copper film. After a layer of pipeline is laid, it is tamped mechanically. During the tamping, the polytetrafluoroethylene dielectric ball and the copper film undergo elastic collision, resulting in an exchange of charges, which are then collected by the copper film. The flap structure can adopt a silicone insulation structure, and a copper transmission contact is provided inside it. The two ends of the copper transmission contact are respectively connected to the copper film and the low-melting-point alloy to form a current loop. When electric current flows through the low-melting-point alloy, the low-melting-point alloy melts due to the electrothermal effect, completing the tubing process of the reinforced grouting pipeline. The molten low-melting-point alloy flows out of the through-hole under the action of gravity and solidifies, and can be used as part of the reinforcement body. In addition, the reinforced grouting pipeline (reinforced inner shell) adopts a carbon fiber mesh structure inside, which effectively improves the pipeline's ability to resist deformation. This kind of piping system converts the impact energy generated during the strong compaction process to realize the power supply of the structure itself, effectively reducing the dependence on external stable power supply during the construction process. It circumvents the problems often seen in traditional biological reinforcement methods, such as uneven distribution of reinforcement slurry, limited reinforcement range, blockage of reinforcement grouting pipelines, and unstable reinforcement effect. It promotes the formation of three-dimensional site-scale reinforcement bodies and achieves an overall improvement in the bearing capacity of the coral sand foundation.

[0027] (3) The connector of the present invention realizes the connection of adjacent pipeline systems through the card slot card buckle structure, and realizes the connection between the reinforced grouting pipeline and the connector structure by utilizing the elastic buckle of the card buckle structure, thereby ensuring the effective movement of the reinforcement slurry, ensuring the tightness of the connector in actual application state, and avoiding the reinforcement slurry leakage caused by the loose connection between the connector and the pipeline system. At the same time, the card buckle structure is designed with a self-locking function, and a firm connection is achieved through structural preload and elastic deformation. It can still maintain a stable position when subjected to strong tamping. The card buckle structure can be formed in one step by injection molding, and its weight is light and the processing technology is simple. At the same time, a monitoring system is integrated at the end of the pipeline system to realize real-time monitoring of the environmental conditions of coral sand strata at different depths, and to transmit real-time data through wireless signals, thereby realizing real-time adjustment of relevant parameters such as the reinforcement slurry ratio. This structural arrangement effectively reduces the manufacturing and transportation costs, provides a guarantee for the effective reinforcement of the coral sand foundation, and solves the problems of the traditional reinforcement method being difficult to implement, low in efficiency, and unsatisfactory treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1Schematic diagram of the coral sand formation and its reinforcement structure according to the present invention;

[0029] Figure 2 Schematic diagram of the reinforcement structure of the present invention; Figure A is a schematic diagram of the connection relationship of the reinforcement structure of different layers, and Figure B is a schematic diagram of the connection relationship of the reinforcement structure of the same layer;

[0030] Figure 3 Schematic diagram of the connection relationship between horizontal pipelines and their auxiliary structures; Figure A is a schematic diagram of the horizontal cross-sectional structure of the pipeline system, and Figure B is a schematic diagram of the longitudinal cross-sectional structure of the pipeline system;

[0031] Figure 4 Schematic diagram of the low-melting alloy flow direction; Figure A is a cross-sectional view of the pipeline under normal conditions, and Figure B is a cross-sectional view of the pipeline after the low-melting alloy is melted;

[0032] Figure 5 Schematic diagram of the connection relationship between the auxiliary structure and connectors of the piping system; Figure A is a schematic diagram of the normal connection relationship of the flap structure, and Figures B, C, and D are schematic diagrams of the connection status of different forms of connectors and the piping system;

[0033] Figure 6 Flow chart of power generation for triboelectric nanogenerator;

[0034] Figure 7 Schematic diagram of the connector connection structure and monitoring system, where Figures A, B, and C are schematic diagrams of the connection relationship between connectors of different forms and the piping system, Figures D and E are schematic diagrams of the connector structure, and Figure E is a schematic diagram of the cross-section of the monitoring system structure;

[0035] Figure 8 This is a schematic flow chart of the coral sand foundation reinforcement method of the present invention;

[0036] The symbols in the accompanying drawings are:

[0037] 1-Coral sand foundation; 2-Bio-grouting reinforcement area; 3-Pipeline system; 31-Normal pipeline; 32-Horizontal pipeline; 321-Epoxy fiberglass shell; 3211-Upper copper film; 3212-Lower copper film; 322-PTFE dielectric ball; 323-Flanged structure; 324-Low melting point alloy; 325-Reinforced inner shell; 3251-Silicone tube wall; 3252-Carbon fiber mesh tube; 4-Second connecting piece; 41-Second clip; 42-Second card board; 5-Monitoring system; 51-pH sensor head; 52-Signal transmitter; 53-Power supply element; 6-First connecting piece; 61-First clip; 62-First card board. DETAILED DESCRIPTION

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] like Figures 1-2 As shown, the present invention provides a coral sand foundation reinforcement device based on bio-grouting, including a piping system 3 for grouting, wherein the piping system 3 comprises a normal pipe 31 with a uniform outer diameter and a horizontal pipe 32. The horizontal pipe 32 is arranged in several layers and laid on the coral sand foundation 1. Two adjacent layers of horizontal pipes 32 are connected by the normal pipe 31. The normal pipe 31 is made of high-strength rigid material and is responsible for the top-down transfer of the reinforcement slurry. The top opening of the normal pipe 31 allows the biological slurry to pass through the normal pipe 31 and enter the horizontal pipe 32.

[0040] like Figures 2 to 5 As shown, the horizontal pipe 32 is provided with a plurality of through holes, and the cross-sectional area of ​​the through holes gradually decreases from the inside to the outside. The through holes are sealed by a low-melting-point alloy 324. The low-melting-point alloy 324 is a truncated cone structure with a wide top and a narrow bottom under normal conditions, and an environmentally friendly alloy such as a tin-bismuth alloy can be used. The pipe wall of the horizontal pipe 32 is provided with a conductive component, and the conductive component is electrically connected to the low-melting-point alloy 324. In other embodiments of the present invention, a heating wire is provided in the through hole, the heating wire is in contact with the low-melting-point alloy 324, and the conductive component is electrically connected to the heating wire. When the heating wire is energized and heated, the low-melting-point alloy 324 can be thermally melted. When the low-melting-point alloy 324 is energized and thermally melted, the biological slurry in the horizontal pipe 32 flows out of the through hole and solidifies in the coral sand.

[0041] During application, the normal pipe 31 and horizontal pipe 32 are laid on the coral sand foundation 1. Current is supplied through the conductive component, causing the low-melting-point alloy 324 to melt and detach from the through-holes, thus forming the horizontal pipes 32. Grout is then injected into the pipe system 3 through the inlet of the normal pipe 31, filling the pipe system and flowing through the through-holes to the external coral sand layer. The slurry solidifies in the coral sand layer, forming the bio-grouting reinforcement area 2, thus completing the reinforcement of the coral sand foundation.

[0042] like Figures 3-4As shown, a group of conductive components corresponds to one low-melting-point alloy 324, and two adjacent conductive components are independent of each other. The conductive components include a power generation element and conductive wires. The power generation element includes an upper copper film 3211, a lower copper film 3212, and a plurality of polytetrafluoroethylene dielectric balls 322. The upper copper film 3211 and the lower copper film 3212 are arranged inside the wall of the horizontal pipe 32. The polytetrafluoroethylene dielectric balls 322 are movably arranged between the upper copper film 3211 and the lower copper film 3212. The upper copper film 3211 and the lower copper film 3212 are respectively connected to the low-melting-point alloy 324 via conductive wires. In the present invention, the horizontal pipeline 32 can be slightly deformed (or elastic) to a certain extent. When the horizontal pipeline 32 is laid, a coral sand layer is blown above the horizontal pipeline 32. After the blowing is completed, a strong compaction operation is performed, that is, the coral sand layer is compacted by manual or mechanical hammering to reduce its porosity. During the compaction process, the horizontal pipeline 32 vibrates or slightly deforms, and the polytetrafluoroethylene dielectric ball 322 inside it can collide and rub with the upper copper film 3211 / lower copper film 3212 to generate current. The generated current is conducted through the wires on the upper copper film 3211 / lower copper film 3212 to form a current loop, converting the impact energy into electrical energy, achieving the functions of power supply and conductivity, and is used for thermal melting of the low-melting-point alloy 324.

[0043] As a further preferred embodiment of the present invention, the horizontal pipeline 32 is further provided with an epoxy fiberglass outer shell 321 and a reinforced inner shell 325. The epoxy fiberglass outer shell 321 is the outermost layer of the pipeline, and the reinforced inner shell 325 is the innermost layer of the pipeline. The power generation element is arranged between the epoxy fiberglass outer shell 321 and the reinforced inner shell 325. The upper copper film 3211 is attached to the inner wall of the epoxy fiberglass outer shell 321, and the lower copper film 3212 is attached to the inner wall of the reinforced inner shell 325. The reinforced inner shell 325 includes a silicone tube wall 3251 and a carbon fiber mesh tube 3252. The carbon fiber mesh tube 3252 is embedded and laid in the silicone tube wall 3251. The reinforced inner shell 325 can play a supporting role. The dense mesh structure can effectively avoid deformation and damage of the pipeline caused by the compaction process, ensure the circulation of the bioreinforcement slurry during the grouting process, and better ensure the effect of bioreinforcement grouting.

[0044] As a further preferred embodiment of the present invention, the horizontal pipe 32 is further provided with a flap structure 323 having the same number of through holes as the through holes, and the flap structure 323 is made of insulating and high-temperature resistant material. The flap structure 323 is disposed within the through hole, with one side of the flap structure 323 fixedly connected to the epoxy fiberglass outer shell 321 and the reinforced inner shell 325, and the other side in contact with the low-melting-point alloy 324. While ensuring a good connection between the epoxy fiberglass outer shell 321 and the reinforced inner shell 325, the flap structure 323 provides a suitable placement for the low-melting-point alloy 324, avoiding the hole obstruction phenomenon that may occur when a single hole is opened in a traditional flower pipe structure under the action of strong compaction, thereby ensuring smooth injection of the bioreinforcement slurry. Copper power transmission contacts are embedded within the flap structure 323. A single flap structure houses only one pair of copper power transmission contacts, each with a wire hole. The copper power transmission contacts are directly connected to the low-melting alloy (or to a heating wire). Wires connect the copper film and the copper contacts. The positive electrode wire connects to the upper portion of the flap structure 323, while the negative electrode wire connects to the lower portion. The significant difference in melting point between the flap structure 323 and the low-melting alloy 324 provides sufficient conditions for the subsequent melting of the low-melting alloy 323 to form the flower tube hole, ensuring proper connection between the remaining structures in the piping system 3 when the low-melting alloy 324 melts to form the flower tube hole.

[0045] like Figure 2 and Figure 7 As shown, in the present invention, the horizontal pipeline 32 includes several horizontal grouting pipes. Two adjacent horizontal grouting pipes are connected by a first connector. The first connector includes a U-shaped pipe or a straight pipe with an outer diameter consistent with the pipeline system. The connecting end of the U-shaped pipe / straight pipe is provided with a first clamping plate, which has a first slot. The horizontal grouting pipe is provided with a first buckle. When the first connector is connected to the horizontal grouting pipe, the first buckle is engaged in the first slot. The U-shaped pipe or straight pipe is connected to the horizontal grouting pipe via four sets of slot and buckle structures.

[0046] like Figure 2 and Figure 7 As shown, in the present invention, the horizontal pipeline 32 and the normal pipeline 31 are connected through the second connecting member 4. The second connecting member 4 includes a hollow shell, which is provided with a horizontal connecting end and a vertical connecting end respectively adapted for the horizontal pipeline 32 and the normal pipeline 31. The horizontal connecting end and the vertical connecting end are respectively provided with a second clamping plate 42, and the second clamping plate 42 is provided with a second clamping slot. The horizontal pipeline 32 and the normal pipeline 31 are respectively provided with a second clamping buckle 41. The clamping structure can be designed as a triangular shape. When the horizontal pipeline 32 and the normal pipeline 31 are connected to the horizontal connecting end and the vertical connecting end respectively, the second clamping buckle 41 is clamped into the second clamping slot. The second connecting member 4 is connected to the horizontal pipeline 32 and the normal pipeline 31 respectively through four sets of clamping slot and clamping structures.

[0047] Both the slot structure and the buckle structure are made of plastic material with a certain strength, which can realize the effective connection between the reinforced grouting pipeline and the connecting parts, effectively avoiding the failure of reinforcement slurry transmission and overflow of slurry at non-preset positions caused by disconnection of the overall reinforcement pipeline system due to loose connection, ensuring the effective transmission of slurry. At the same time, the buckle structure is simple and easy to implement.

[0048] As a further preference of the present invention, Figure 7 As shown, a monitoring system 5 is provided at the end of the horizontal pipeline 32. The monitoring system 5 is connected to the pipeline system in a point-to-point manner, that is, the two are connected under normal conditions. When the tamping force is applied, the point-to-point connection fractures brittlely and the two are separated. The monitoring system 5 includes a pH sensor head 51, a signal transmitter 52, and a power supply element 53. The power supply element 53 is used to supply power to the pH sensor head 51 and the signal transmitter 52. The pH sensor head 51 is used to detect the pH of the grouting area and transmit it to the main control system through the signal transmitter 52. The power supply element 53 can be a battery component, which provides electrical energy to other components through a wire. This structure effectively realizes the monitoring of the acidic and alkaline environment in the reinforced stratum, provides a real-time basis for adjusting the pH of the reinforcement slurry, reduces the influence of the stratum's own environmental conditions on the bio-grouting reinforcement effect, effectively improves the reinforcement effect of the bio-grouting reinforcement on the coral sand foundation 1, and realizes adjustable and controllable bio-grouting reinforcement to a certain extent.

[0049] The reinforcement method of the coral sand foundation reinforcement device based on bio-grouting of the present invention comprises the following steps:

[0050] Step 1: Pre-fill a layer of coral sand on the coral sand foundation 1.

[0051] Step 2: Lay the first-layer horizontal pipe 32 on the surface of the coral sand formation. Connect the first-layer normal pipe 31 to the connection end of the first-layer horizontal pipe 32. Seal the normal pipe 31 to prevent coral sand from entering the pipe during subsequent filling. Then, fill the coral sand above the first-layer horizontal pipe 32. After filling, perform dynamic compaction until the low-melting-point alloy 324 in the first-layer horizontal pipe 32 is completely melted. The reserved height of the normal pipe system should not exceed 20 cm.

[0052] Step 3: Unblock the normal pipeline 31 and lay the second layer of horizontal pipeline 32 on the surface of the compacted layer. The lower connecting end of the second layer of horizontal pipeline 32 is connected to the first layer of normal pipeline 31, and the upper connecting end is connected to the second layer of normal pipeline 31. The second layer of normal pipeline 31 is blocked, and then coral sand is blown over the second layer of normal pipeline 31. After the blowing and filling is completed, a strong compaction operation is performed until the low-melting-point alloy 324 of the second layer of horizontal pipeline 32 is completely melted.

[0053] Step 4: Repeat step 3 until the designed height is reached, completing the laying of all horizontal pipelines 32.

[0054] Step 5: Grouting is performed through the inlet of the uppermost normal pipeline 31 into the horizontal pipelines 32 of each layer. The slurry is injected into the coral sand layer through the through-holes, causing a mineralization reaction to solidify the coral sand layers, thereby completing the coral sand foundation reinforcement.

[0055] In the present invention, the slurry is a premixed solution of urea-hydrolyzing microorganisms (Bacillus pasteurianus) and urea-calcium source. The premixed solution has a low pH characteristic. During grouting, the premixed solution is injected into the pipeline system 3 and flows out from the through hole of the pipeline system (3) to reinforce the coral sand layer. Alternatively, the slurry is divided into a urea-hydrolyzing microorganism culture solution (Bacillus pasteurianus culture solution) and a urea-calcium source solution. During grouting, the urea-hydrolyzing microorganism culture solution is first injected, and the culture solution is allowed to stand for a period of time to allow the bacteria to adhere to the coral sand layer. Then, the urea-calcium source solution is injected in batches to perform a curing reaction. Before the cyclic reinforcement grouting, the reinforcement slurry should be adjusted according to the underground environmental information collected by the comprehensive monitoring system to achieve the optimal reinforcement effect.

[0056] The present invention applies a microbial-induced carbonate precipitation reinforcement method. Before use, Bacillus pasteurianus should be screened for multi-generation activity, salt tolerance and other properties. Subsequently, the screened Bacillus pasteurianus is cultivated in a seawater-like solution and screened for a second multi-generation. During the second multi-generation screening process, the cultivation environment is gradually improved to gradually approach the real seawater environment, and a third multi-generation screening is performed in the real seawater environment to ensure that its salt tolerance and calcium carbonate cement formation ability tend to be stable and do not degenerate, and finally obtain a strain that is adapted to the seawater working environment of the engineering site. The seawater-like solution used in the above process should be dried by a drying method on a certain amount of real seawater, and 1 / 3-1 / 2 of the dried product is prepared to obtain a solution with the same volume as the real seawater before drying, which is referred to as a seawater-like solution. The urease-induced carbonate precipitation reinforcement method does not require a microbial passage screening process. The amount of urease added to the biological reinforcement slurry can be controlled in a timely manner according to the needs of on-site construction.

[0057] Application principle of the present invention:

[0058] Under the action of dynamic compaction, the coral sand particles break up, reducing the porosity of the coral sand foundation and increasing the density of the ground. This changes the arrangement and position of the coral sand particles, causing the piping system 3 arranged in the coral sand foundation 1 to deform or vibrate. This causes the polytetrafluoroethylene dielectric balls 322 in the horizontal piping 32 to collide and rub against the upper and lower copper films 3211 and 3212. This causes an equal exchange of charge between the polytetrafluoroethylene dielectric balls 322, the upper and lower copper films 3211 and 3212, creating a potential difference and thus a current. This current is conducted through the conductors on the upper and lower copper films 3211 and 3212, which are connected via copper transmission contacts arranged above and below the flap structure 323, forming a circuit loop. The electrical energy generated by the friction during the dynamic compaction process melts the low-melting-point alloy 324 in the flap structure 323, completing the process of forming the pipe system 3. The coral sand foundation 1 is circulated with a bioreinforcement slurry, which catalyzes the hydrolysis of urea through urease to produce carbonate ions. The carbonate ions combine with the calcium ions in the bioreinforcement slurry to induce the production of calcium carbonate cement, which fills and reinforces the gaps in the coral sand foundation 1, thereby increasing the density of the coral sand stratum and thus enhancing the bearing capacity of the coral sand foundation. The coral sand foundation 1 is reinforced using the pipeline system 3 after the grouting is completed, improving the mechanical properties of the soil and increasing the bearing capacity of the stratum. The above reinforcement methods work synergistically to achieve multi-dimensional reinforcement of the coral sand foundation 1.

[0059] The present invention utilizes the layered filling method of islands and reefs to arrange a multi-layer assembled reinforced pipe system to achieve soil reinforcement, and uses it as a reinforced grouting pipe in the two-stage bio-grouting reinforcement process. The energy in the dynamic compaction process is efficiently utilized, and the impact energy in the dynamic compaction process is converted by means of polytetrafluoroethylene dielectric balls 322 attached to the pipe system. The pipe system is treated with a flower pipe by using the electrothermal effect. After the splicing is completed, bio-grouting reinforcement is carried out to form calcium carbonate precipitation to fill the gaps between the coral sand particles, thereby improving the density of the coral sand foundation. Through the two-stage reinforcement process, a multi-dimensional three-dimensional reinforcement body of the coral sand foundation is formed, and finally the bearing capacity of the newly built coral sand island reef foundation is improved. The detailed technical principles are as follows: give full play to the characteristics of the filling process, realize the layer-by-layer arrangement of the reinforced pipe system in the coral sand foundation, reinforce the coral sand foundation, and achieve a preliminary enhancement of the bearing capacity of the newly built coral sand island reef foundation. In the reinforced grouting system, a polytetrafluoroethylene (PTFE) dielectric ball is placed between the epoxy fiberglass shell and the silicone tube. The inner walls of both the epoxy fiberglass shell and the silicone tube are coated with a copper film, which serves as a friction layer. During dynamic compaction, the dielectric ball undergoes normal displacement, causing friction with the copper film and exchanging charge, creating a potential difference. The upper copper film serves as the positive electrode, while the lower copper film serves as the negative electrode. Wires are connected to the two ends of the flap structure to form a circuit. The flap structure is sealed with a low-melting-point alloy. Due to the electrothermal effect, the low-melting-point alloy heats and melts under the influence of the current, completing the tubularization process of the pipeline system. Circulating bioreinforcement slurry, through mineralization reactions, forms a calcium carbonate cement, filling and reinforcing the pores between the coral sand grains, increasing the density of the coral sand foundation and achieving a secondary increase in the bearing capacity of the newly constructed island reef foundation. These processes work synergistically to achieve multi-dimensional reinforcement of the coral sand foundation.

[0060] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A coral sand foundation reinforcement device based on bio-grouting, characterized in that: including piping system (3); The pipeline system (3) includes a normal pipeline (31) and a horizontal pipeline (32); The horizontal pipelines (32) are arranged in several layers and laid on the coral sand foundation (1). The upper and lower adjacent horizontal pipelines (32) are connected through the normal pipeline (31). The top opening of the normal pipeline (31) can be used to pass biological slurry, and the biological slurry enters the horizontal pipeline (32) through the normal pipeline (31); The horizontal pipeline (32) is provided with a plurality of through holes, and the through holes are blocked by a low-melting-point alloy (324); a conductive component is provided on the wall of the horizontal pipeline (32), and the conductive component is electrically connected to the low-melting-point alloy (324); when the low-melting-point alloy (324) is energized and melted, the biological slurry in the horizontal pipeline (32) flows out from the through holes and solidifies in the coral sand.

2. The coral sand foundation reinforcement device based on bio-grouting according to claim 1 is characterized in that: The conductive component includes a power generation component and a conductive wire; The power generation element comprises an upper copper film (3211), a lower copper film (3212) and a plurality of polytetrafluoroethylene dielectric balls (322); the upper copper film (3211) and the lower copper film (3212) are arranged inside the wall of the horizontal pipeline (32); the polytetrafluoroethylene dielectric balls (322) are movably arranged between the upper copper film (3211) and the lower copper film (3212); the upper copper film (3211) and the lower copper film (3212) are respectively connected to the low melting point alloy (324) via conductive wires; When the coral sand layer above the horizontal pipe (32) is rammed, the horizontal pipe (32) vibrates or deforms, and the polytetrafluoroethylene dielectric ball (322) collides and rubs with the upper copper film (3211) / lower copper film (3212) to generate current. The generated current is conducted through the wires on the upper copper film (3211) / lower copper film (3212), forming a current loop, thereby converting the ramming energy into electrical energy.

3. The coral sand foundation reinforcement device based on bio-grouting according to claim 2, characterized in that: The horizontal pipeline (32) is further provided with an epoxy glass fiber outer shell (321) and a reinforced inner shell (325); The power generation element is arranged between the epoxy fiberglass outer shell (321) and the reinforced inner shell (325), the upper copper film (3211) is attached to the inner wall of the epoxy fiberglass outer shell (321), and the lower copper film (3212) is attached to the inner wall of the reinforced inner shell (325); The reinforced inner shell (325) comprises a silicone tube wall (3251) and a carbon fiber mesh tube (3252), and the carbon fiber mesh tube (3252) is embedded and laid in the silicone tube wall (3251).

4. The coral sand foundation reinforcement device based on bio-grouting according to claim 3 is characterized in that: The horizontal pipeline (32) is also provided with opening structures (323) having the same number as the through holes; The flap structure (323) is arranged inside the through hole, one side of the flap structure (323) is fixedly connected to the epoxy glass fiber outer shell (321) and the reinforced inner shell (325), and the other side is in contact with the low melting point alloy (324).

5. The coral sand foundation reinforcement device based on bio-grouting according to claim 1, characterized in that: The cross-sectional area of ​​the through hole gradually decreases from the inside to the outside.

6. The coral sand foundation reinforcement device based on bio-grouting according to claim 1, characterized in that: The horizontal pipeline (32) includes a plurality of horizontal grouting pipes, and two adjacent horizontal grouting pipes are connected through a first connecting piece; The first connecting member includes a U-shaped tube or a straight tube, and the connecting end of the U-shaped tube / straight tube is provided with a first clamping plate, and a first clamping slot is opened on the first clamping plate. The horizontal grouting pipe is provided with a first buckle. When the first connecting member is connected to the horizontal grouting pipe, the first buckle is clamped in the first clamping slot.

7. The coral sand foundation reinforcement device based on bio-grouting according to claim 1, characterized in that: The horizontal pipeline (32) and the normal pipeline (31) are connected via a second connecting piece (4); The second connecting member (4) comprises a hollow shell, wherein the hollow shell is provided with a horizontal connecting end and a vertical connecting end respectively adapted to the horizontal pipeline (32) and the normal pipeline (31); the horizontal connecting end and the vertical connecting end are respectively provided with a second clamping plate (42), and the second clamping plate (42) is provided with a second clamping groove, and the horizontal pipeline (32) and the normal pipeline (31) are respectively provided with a second clamping buckle (41). When the horizontal pipeline (32) and the normal pipeline (31) are respectively connected to the horizontal connecting end and the vertical connecting end, the second clamping buckle (41) is clamped in the second clamping groove.

8. The coral sand foundation reinforcement device based on bio-grouting according to claim 1, characterized in that: A monitoring system (5) is provided at the end of the horizontal pipeline (32); The monitoring system (5) includes a pH sensor head (51), a signal transmitter (52) and a power supply element (53); The power supply element (53) is used to supply power to the pH sensor head (51) and the signal transmitter (52); the pH sensor head (51) is used to detect the pH of the grouting area and transmit the pH to the main control system via the signal transmitter (52).

9. The method for reinforcing a coral sand foundation reinforcement device based on bio-grouting according to any one of claims 2 to 8, characterized in that: The following steps are involved: S1, pre-filling a layer of coral sand on the coral sand foundation (1); S2, laying the first-layer horizontal pipeline (32) on the surface of the coral sand stratum to be filled, connecting the first-layer normal pipeline (31) with the connecting end of the first-layer horizontal pipeline (32), and blocking the normal pipeline (31), and then filling the coral sand above the first-layer horizontal pipeline (32); after the filling is completed, performing a strong compaction operation until the low-melting-point alloy (324) of the first-layer horizontal pipeline (32) is completely melted; S3, unblocking the normal pipeline (31), laying the second layer of horizontal pipeline (32) on the surface of the compacted layer, connecting the lower connecting end of the second layer of horizontal pipeline (32) to the first layer of normal pipeline (31), and connecting the upper connecting end to the second layer of normal pipeline (31), and blocking the second layer of normal pipeline (31), and then filling coral sand above the second layer of normal pipeline (31); after the filling is completed, performing a strong compaction operation until the low melting point alloy (324) of the second layer of horizontal pipeline (32) is completely melted; S4, repeat step S3 until the design height is reached, completing the laying of all horizontal pipelines (32); S5. Grouting is performed through the uppermost normal pipeline (31) into the horizontal pipelines (32) of each layer. The slurry is injected into the coral sand layer through the through holes, causing a mineralization reaction to solidify the coral sand layers, thereby completing the coral sand foundation reinforcement.

10. The coral sand foundation reinforcement device based on bio-grouting according to claim 9, characterized in that: In the steps S2 and S3, the dynamic compaction operation specifically includes: compacting the coral sand layer above the horizontal pipeline (32); During the tamping, the horizontal pipe (32) vibrates or deforms, and the polytetrafluoroethylene dielectric ball (322) collides and rubs with the upper copper film (3211) / lower copper film (3212) to generate current. The generated current is conducted through the wires on the upper copper film (3211) / lower copper film (3212), forming a current loop, converting the tamping energy into electrical energy, and causing the low melting point alloy (324) of the horizontal pipe (32) to melt.

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