Underground diaphragm wall construction method without disturbing surrounding existing structures

Abstract

The invention relates to an underground diaphragm wall construction method without disturbing surrounding existing structures, which comprises the following steps of: carrying out geological re-exploration on a related area before construction, analyzing and obtaining the geological state of the corresponding area according to a re-exploration result, and analyzing and judging the influence of the geological state of each part on diaphragm wall construction and a diaphragm wall. Treatment measures are adopted for the unfavorable geology influencing the diaphragm wall construction and / or the diaphragm wall, and the influence of the unfavorable geology on the diaphragm wall construction and the diaphragm wall is eliminated; or the design scheme of the anti-seepage wall is modified based on the unfavorable geology influencing the construction of the anti-seepage wall and / or the anti-seepage wall, and the influence of the unfavorable geology on the construction of the anti-seepage wall and the anti-seepage wall is avoided. By means of the method, the underground structure and the geological condition of the corresponding area can be fully known before construction, and passivity and loss caused by the fact that relevant conditions are not fully known are avoided.

Description

Technical Field

[0001] The invention relates to a method for constructing an underground anti-seepage wall without disturbing surrounding existing structures. Background Art

[0002] The quality and location of existing underground structures (for example, underground structures) and the geological conditions of the surrounding areas affect the construction of new cut-off walls. Improper equipment selection, improper control of the mud circulation system and various mud indicators will also affect the construction or quality of the project. At present, the location of the new cut-off wall is usually determined based on the existing underground structure archives and geological data of the relevant area, and the cut-off wall design and cut-off wall construction process design are implemented to avoid existing underground structures such as underground structures. The construction unit conducts construction according to the design. However, due to incomplete and erroneous data in some cases, unexpected problems will inevitably be encountered during the construction process. Although some problems can be solved by relevant remedial measures during construction, it will still cause unnecessary cost increases and time delays, and even lead to construction failure. For example, Chinese patent document CN117569263A discloses a dam anti-seepage wall and its construction method, including temporary works, anti-seepage wall drilling, concrete pouring to form an anti-seepage wall, anti-seepage wall slot section connection, through-wall curtain drilling and drilling grouting and core wall base pouring, the anti-seepage wall body is divided into an anti-seepage wall main body section, an anti-seepage wall upper part and an anti-seepage wall lower part; the anti-seepage wall body is coaxially arranged with the clay core wall, and curtain grouting is arranged under the anti-seepage wall to form a reliable anti-seepage system; before pouring the anti-seepage wall, the construction accuracy is determined by zoning the dam and calculating the drilling depth of each part; during the construction of the anti-seepage wall, a construction mode combining excavation and construction of a construction platform with half-excavation and half-filling construction of a construction platform is adopted to clarify the exact position of the foundation rock layer of the base and reduce the difficulty of subsequent excavation of the base. Chinese patent document CN117845993A discloses a construction method of a composite vertical anti-seepage isolation wall for a landfill, comprising the following steps: step 1, drilling holes in the proposed vertical anti-seepage wall by curtain grouting, the holes are symmetrically arranged along the central axis of the proposed vertical anti-seepage wall, and grouting is performed after flushing the holes, and the grouting height is more than 0.5m higher than the interface of the dense layer / loose layer; step 2, after the grouting is completed, a concrete guide wall is built on both sides of the proposed vertical anti-seepage wall, and the wall is cured for 7-14 days; then a trench is excavated in the proposed vertical anti-seepage wall area until the interface of the dense layer / loose layer; step 3, a steel plate coated with epoxy resin is inserted at the intersection of the trench axis and the interface of the dense layer / loose layer, and the top of the steel plate is flush with the grouting horizontal surface in the drill hole; the trench is protected by bentonite slurry; step 4, casting the vertical anti-seepage isolation wall; step 5, after the casting is completed, a layer of in-situ soil is covered on the top of the vertical anti-seepage isolation wall. Chinese patent document CN115748601A discloses a method for repairing dam leakage, which includes the following steps: S1: material preparation; S2: construction preparation, which also includes preparation of a construction platform, and the preparation of the construction platform includes excavation and filling; S3: anti-seepage wall construction, which also includes setting up embedded pipes; S4: anti-seepage reinforcement construction.The dam leakage repair method provided by the present invention can greatly improve the integrity of the dam leakage repair work by completely repairing the concrete anti-seepage wall of the dam body and the dam foundation cover layer, the anti-seepage reinforcement of the dam foundation bedrock, the anti-seepage reinforcement of the anti-seepage wall connection parts, and the anti-seepage reinforcement processing parts of the dam culvert, thereby avoiding the dam foundation leakage from reducing the benefits of the reservoir and the uplift pressure at the bottom of the dam, effectively avoiding the occurrence of erosion of the dam foundation rock and soil and instability of the dam foundation, and effectively improving the overall stability of the dam. Since the existing anti-seepage wall research and practice focus on the anti-seepage wall construction process, the geological conditions of the relevant area are often not re-explored before construction. Once bad geology is encountered, it often becomes passive, resulting in unnecessary losses. Summary of the invention

[0003] The purpose of the present invention is to fully understand the underground structure and geological conditions of the corresponding area before construction, so as to avoid passivity and losses caused by failure to fully understand the relevant conditions.

[0004] The technical solution of the present invention is: a method for constructing an underground anti-seepage wall without disturbing the existing surrounding structures, before the construction, geological re-exploration (re-exploration based on the existing geological related data) of the relevant area (the area that affects the construction of the anti-seepage wall and the anti-seepage wall) is carried out, the geological state of the corresponding area is obtained according to the analysis of the re-exploration results, the influence (negative influence) of the geological conditions of each part on the construction of the anti-seepage wall and the anti-seepage wall is analyzed and judged, and treatment measures are adopted for the unfavorable geology that affects the construction of the anti-seepage wall and / or the anti-seepage wall to eliminate the influence of the unfavorable geology on the construction of the anti-seepage wall and the anti-seepage wall; or, based on the unfavorable geology that affects the construction of the anti-seepage wall and / or the anti-seepage wall, the anti-seepage wall design plan is modified to avoid the influence of the unfavorable geology on the construction of the anti-seepage wall and the anti-seepage wall.

[0005] Preferably, the geological re-exploration is carried out by using natural source surface wave advance detection technology.

[0006] Furthermore, it is preferred to use micro-motion B-ultrasound technology to implement the geological re-exploration.

[0007] When implementing geological re-exploration, a survey network can be constructed using parallel survey lines or grid survey lines.

[0008] The geological conditions include the conditions of existing underground structures and the surrounding (within the relevant area) media conditions.

[0009] The status of the existing underground structures includes two situations: the existence of existing underground structures and the absence of existing underground structures.

[0010] The adverse geology includes any one or more of loose / low density, weak, easy to flow, easy to erode (for example, mud erosion during construction), collapse, voids, high water level and high stress.

[0011] The relevant area includes the area around the cut-off wall (design location), especially the area between the existing underground structures and the cut-off wall.

[0012] The impact on the construction and construction of the cut-off wall can be determined based on the characteristics of the adverse geology and the scope of the area in which it is located.

[0013] Furthermore, when the cut-off wall overlaps (including partial overlap) with an existing underground structure, it is preferred to modify the cut-off wall design.

[0014] Furthermore, when the construction of the cut-off wall is affected or the adverse geology of the cut-off wall is not suitable and / or difficult to be effectively treated, it is preferred to modify the design of the cut-off wall.

[0015] Preferably, in the construction of the anti-seepage wall hole making, the project adopts a combination of the "grabbing method" and the "drilling and splitting method", that is, the upper covering layer is grabbed with a grab bucket, and the bottom bedrock is drilled and split into grooves with a rotary drilling rig (XR240E).

[0016] Preferably, during the construction of the hole making in the anti-seepage wall, a grab bucket is used to grab the upper covering layer, and a rotary drilling rig is used to drill and split the bottom bedrock into a groove.

[0017] Preferably, in trenching construction, three grips are used to form trenches, first gripping the main holes on both sides and then gripping the small wall in the middle.

[0018] Preferably, the drilling and splitting method is used to make holes and grooves on the bedrock. After the grooves extend to the bedrock, the main hole positions are set alternately, and the auxiliary hole positions are between adjacent main holes. The auxiliary holes (after drilling) overlap with the adjacent edge parts between adjacent main holes to form a groove shape. After the main holes on both sides of the auxiliary holes are completed, the auxiliary holes are drilled and split (a rotary drilling rig can be used).

[0019] The beneficial effects of the present invention are as follows: since geological re-exploration of the corresponding area is carried out before construction, the geological conditions including the conditions of the existing underground structures can be more fully understood, and then it is effectively analyzed and determined whether there is unfavorable geology that affects the construction of the cut-off wall and the cut-off wall after construction. In the case of such unfavorable geology, necessary treatment measures can be adopted before construction to avoid the influence on the construction of the cut-off wall and the cut-off wall, or in the case where it is not appropriate or difficult to adopt effective treatment measures, the influence of unfavorable geology on the construction of the cut-off wall and the cut-off wall can be avoided by modifying the cut-off wall design, thereby avoiding the influence of unfavorable geology on the construction of the cut-off wall and the cut-off wall due to the failure to fully understand the geological conditions. The passivity and losses caused by understanding the relevant situation can be avoided; since the micro-motion B-ultrasound technology or other natural source surface wave advance detection technology is used to implement geological re-exploration, the cost is low, the data is easy to obtain, it is environmentally friendly and pollution-free, the anti-interference ability is strong, the exploration depth is large, and the operation is simple and safe; since the measurement network is constructed by parallel measurement lines or grid-shaped measurement lines, it is suitable for occasions where there are existing anti-seepage walls and / or occasions where the space is small; since it can also cooperate with the implementation of optimized mechanical equipment and hole-making technology, reasonable configuration of mud circulation system and mud quality control, and selection of appropriate catheter lifting devices, the construction quality of the anti-seepage wall is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an example diagram of the arrangement of the linear array survey line involved in the present invention; Figure 2 yes Figure 1 The natural source surface wave advance detection diagram of the example; Figure 3 The present invention relates to a schematic diagram of the working sequence of a rotary drilling rig for making holes and grooves on bedrock. DETAILED DESCRIPTION

[0021] When a new cutoff wall is adjacent to an existing structure (for example, an old cutoff wall), the quality and position of the existing underground structure will affect the construction of the new cutoff wall. If the new cutoff wall is improperly positioned or constructed in an improper manner, it may cause problems such as collapse of the soil between the two walls. The present invention solves the technical problem of constructing an underground cutoff wall without disturbing the surrounding existing structures by re-exploring the distribution range of the existing underground structure, and coordinating the optimization of mechanical equipment and hole-making technology, reasonably configuring the mud circulation system and mud quality control, and optimizing the manufacture of the conduit lifting device.

[0022] The specific implementation modes of the present invention are described below with reference to examples.

[0023] The present invention comprises the following steps: 1. Detection (re-exploration) of existing underground structures / regional geological detection (re-exploration) In one example, the distance between the newly built concrete anti-seepage wall and the old anti-seepage wall is 0.8m. The quality of the old anti-seepage wall and the structure of the bedrock strata below it, as well as whether they will affect the construction of the new anti-seepage wall, are unclear. The newly built anti-seepage wall is further penetrated into the rock by 1m based on the penetration of the original anti-seepage wall. As the distance between the new and old anti-seepage walls is close, the risk of landslides is very likely to occur.

[0024] To provide a basis for solving such problems, the natural source surface wave detection technology was used for the first time on the dam body to detect the distribution range of the old anti-seepage wall. Before the construction of the project, the natural source surface wave advance detection technology was used to conduct underground detection in the relevant areas, arrange micro-motion B-ultrasound profiles, analyze the change law of the surface wave velocity of each profile, and obtain the distribution range, structural quality and damage of the bedrock under the original structure. Based on this, the degree of impact on the construction of the project can be further accurately inferred, eliminating the construction risk problem of possible safety accidents due to the close distance between the new and old anti-seepage wall structures.

[0025] First, it is necessary to collect information on the topography of the survey area, external interference sources, geological data, on-site environment, types of above-ground and underground engineering facilities and their distribution (for example, the original topography of the construction site, the specific position of the top of the old anti-seepage wall, the plane position of the new anti-seepage wall, the impact of the road, wave-breaking wall and lamp poles on the top of the dam on the construction of the new anti-seepage wall, the underground pipelines such as wires and cables within the scope of the new anti-seepage wall, the geological conditions of the dam, the working environment of the construction site, the mechanical equipment and layout, the determination of the guide wall position and elevation, etc.), verify the conformity and relevance of the collected data, investigate the main safety risk sources affecting the detection work, and analyze their adverse effects on the on-site detection work.

[0026] According to the purpose of detection, on-site topography, geology and geophysical detection conditions, select typical sections to carry out experimental tests, determine the effectiveness and suitability of micro-seismic detection methods, determine the array type and acquisition parameters, and design measurement points and lines. Measurement points and lines are arranged according to exploration points and exploration lines. Parallel measurement lines or grid-shaped measurement lines can be used to form a measurement network (see Figure 1 ), the density of the survey network is determined according to the complexity of geological conditions and detection conditions. The measurement points and acquisition unit positions are measured and positioned using RTK (Real-time kinematic). The consistency check between the instrument and the acquisition unit is performed before and after the formal detection. The collection time of the consistency check record should be 10 minutes to 30 minutes; the consistency check record between the instrument and the acquisition unit is analyzed and evaluated by visual or software analysis methods; the collection parameters of the consistency check are the same as those of the formal detection work.

[0027] The length of data collection time is determined based on factors such as detection depth, accuracy, and environmental interference, to meet the needs of extracting qualified dispersion curve data that meets the task requirements. During data collection, prevent human vibration interference near the collection unit; monitor micro-motion signals during the collection process, record the abnormal period when abnormalities are found, and eliminate the fault and re-collect when abnormalities are found in the collection unit; after the collection work is completed, store the data in a timely manner and make data backups, conduct quality inspections on the original data and organize the data, and form a results report.

[0028] The domestically produced WD-1 micro-motion intelligent exploration instrument can be used to implement the above-mentioned on-site detection. The device has a frequency bandwidth of 0.5 to 4000 Hz, a sampling rate selectable between 1 and 20 ms, a maximum acquisition time of 1 hour, 10 channels, a detection depth of 200 m, a weight of 7 kg, a power supply voltage of DC12 V, and a storage medium of CF card, which can meet the detection needs under normal circumstances.

[0029] In the above example, four micro-motion B-ultrasound profiles were arranged along the top of the old cut-off wall, with the two middle measuring lines arranged at the top edge of the old cut-off wall and the other two 0.8m outside the top edge of the old cut-off wall. The distance between each measuring line was 0.8m, and the measuring length of each micro-motion B-ultrasound profile was 95m. There were three measuring frames in total, with sizes of 40m, 40m, and 15m. The measuring depth of each micro-motion B-ultrasound profile was 40m.

[0030] 2. Analysis of detection results (regional geological analysis) According to the distribution of surface wave apparent layer velocity, the strata above the bedrock vary greatly, with the main strata being the original dam body filling, sandy clay and sandy loam with gravel layers, and the bedrock being siliceous shale and quartzite. Specifically: the main components of the original dam body filling are asphalt pavement and cushion layer, with backfill gravel underneath, with a surface wave apparent layer velocity of 130-300m / s and a rock layer thickness of 8.0-15.0m; the surface wave apparent layer velocity of the gravel layer is 300-500m / s and a rock layer thickness of 6.0-15.0m; the surface wave apparent layer velocity of the gravel layer is 300-450m / s and the cover layer thickness is 6.0-15.0m; the surface wave apparent layer velocity of the quartzite is 200-300m / s, which is speculated to be quartzite crushing; the quartzite The surface wave apparent layer velocity is 300-400m / s, which is speculated to be that the quartzite is relatively broken; the surface wave apparent layer velocity of quartzite is 400-600m / s, and the thickness is greater than the detection depth; in the fault fracture zone, the surface wave apparent layer velocity is 400-600m / s; the surface wave apparent layer velocity of siliceous shale is 200-300m / s, which is speculated to be that the siliceous shale is broken; the surface wave apparent layer velocity of siliceous shale is 300-450m / s, which is speculated to be that the siliceous shale is relatively broken; the surface wave apparent layer velocity of siliceous shale is 450-800m / s, and the thickness is greater than the detection depth.

[0031] Figure 2Three detection images (grayscale images, the original images are color images) of the above examples are shown. From the analysis of the first image, it can be ruled out that the old anti-seepage wall is tilted to the position of the new anti-seepage wall on a large scale. From the analysis of the second image, the shallow layer (about 10 meters) is filled material. In the section of 28 to 75 meters in length, the speed of the filling material is significantly higher than the corresponding position in the first image. It is speculated that there is a possibility that the anti-seepage wall is tilted to this position. From the third image, it can be inferred that the main part of the old anti-seepage wall is located at the designed position.

[0032] The conclusion drawn from this is: if the new cutoff wall can be guaranteed to be built vertically downwards, it will not affect the construction of the new cutoff wall. If the construction of the new cutoff wall is inclined towards the old cutoff wall, it is easy to hit the edge or neck of the old cutoff wall.

[0033] By analyzing the variation of surface wave velocity in each section, we can obtain the distribution range of the old anti-seepage wall, the quality of the wall and the damage of the underlying bedrock, and further accurately infer the impact of the old anti-seepage wall on the construction of the project, eliminating the construction risk of safety accidents that may occur due to the close distance between the new and old walls. At the same time, this technology can be used to re-explore the stratum structure and structural distribution, solving the problem of insufficient exploration accuracy due to the inability to fully explore the reservoir during the high water level operation period.

[0034] 3. Treatment of unfavorable geology When adverse geology or underground defects / diseases that affect the construction or quality of the cut-off wall are detected, necessary countermeasures can be adopted, such as pressure grouting, pouring concrete, lowering the groundwater level, etc. in the defective area, and, if necessary, modifying the cut-off wall location or other related designs.

[0035] 4. Hole making in anti-seepage wall 1) Machine selection Combined with the actual hydrological and geological conditions, a trenching machine is selected to cooperate with a rotary drilling rig for drilling and splitting construction. The rotary drilling rig not only greatly improves the construction speed and significantly reduces the construction cost, but also has obvious advantages in terms of construction quality.

[0036] 2) Hole forming construction method The project adopts a combination of "grabbing method" and "drilling and splitting method" for construction, that is, the upper covering layer is grabbed with a grab bucket, and the bottom bedrock is drilled and split into grooves with a rotary drilling rig (XR240E). When drilling holes, first, the inclination of the hole should be measured at any time, and the deviation should be corrected in time if it is found; second, the mud quality and mud surface height should be maintained during construction to prevent leakage and hole collapse; third, according to geological data, when the borehole is close to the bedrock surface, timely and accurate sampling should be carried out to ensure that the depth of the wall embedded in the bedrock meets the requirements. For the upper covering layer of soil, a groove forming machine is used to directly grab the groove. The groove forming method adopts three grabs, first grab the main holes on both sides and then grab the small wall in the middle. According to the formation conditions, the length of the groove section is divided into 6.2 meters. After drilling into the bedrock, the rotary drilling rig drilling and splitting method is used for construction. According to the main hole of 1-1.2 meters, the main hole is constructed first, and after the adjacent main hole is completed, the secondary hole is drilled and split until the groove is formed (see Figure 3 as shown).

[0037] The working width of the grab bucket is 2.8m, and three grab buckets are required to complete a standard slot section. When the grab bucket reaches the bedrock, a rotary drill is used to drill holes until the designed position is reached.

[0038] There are verticality display devices on the trenching machine and rotary drilling rig. When the deviation is greater than 1 / 300, correction work will be carried out.

[0039] There are three methods for trenching correction: one is to use the grab's own correction device (eight correction plates); the second is to use the grab's own rotating head to rotate the grab 180 degrees every 3-5 grabs, and flip it back and forth to offset the deflection caused by the trenching process; the third is to replace the bucket teeth on both sides of the grab, increase the width and height of the bucket teeth in the opposite direction of the deflection, and correct the grab back.

[0040] 5. Mud circulation According to the requirements of hole making construction, mud circulation is implemented.

[0041] 1) Pulping equipment An NJ-600 high-speed mixer is used to make pulp, and a pulping station is built to centrally produce and supply mud.

[0042] 2) Storage equipment assembly The mud storage equipment is a combined assembled box, which can be one set or multiple sets. They are interconnected by DN200 steel pipes. The layout can be flexibly adjusted according to the site occupation.

[0043] 3) Slurry supply and return pipelines The slurry supply pipeline is a DN200 steel pipe that connects all the mud boxes. A slurry supply pump is set at the front end to send the mud into the slot hole. The return slurry pipeline is a hose that uses a mud pump to pump the mud into the mud purification device. After purification, the slurry is returned to the mud box for storage and recycling.

[0044] 4) Mud purification device The mud purification device adopts ZX-100 / 30 type, with a liquid processing capacity of 100m³ / h and a slag screening capacity of 25-50t / h. 5) Mud anti-sedimentation device In order to prevent mud from settling, continuous aeration is required to keep the mud particles in suspension. The anti-sedimentation device uses an air compressor to continuously supply air to the mud box through an air supply pipe.

[0045] 6) Clean the hole and change the slurry The hole is cleaned by pump suction reverse circulation method. A single-type sand and gravel pump is used to suck the mud at the bottom of the hole. After being processed by a ZX-200 mud purifier through a discharge pipe, the mud is returned to the trough hole to suspend the sediment.

[0046] 7) Mud recovery and treatment The mud circulation trenching process focuses on solving the problems of mud with a large amount of soil debris in the trenching stage and mud replaced from pouring concrete. The recovered mud is precipitated after removing larger soil debris through a vibrating screen, and then removed with a cyclone to remove smaller particles of soil debris. If it still does not meet normal use conditions, it will be chemically treated. Mud is prone to gelation when pouring concrete. As the mud skin forming characteristics of the slurry weaken, the viscosity increases, the separation of soil debris becomes difficult, and the flow resistance in the pipe increases, the slurry performance will deteriorate and it needs to be chemically treated. Generally, it is treated with a dispersant before the soil debris separation treatment. After the mud is chemically treated, various indicators of the mud are tested. If necessary, slurry materials can be added for regeneration and modulation. The regenerated and modulated mud is sent to the slurry storage tank and reused after the newly added materials and the treated mud are fully mixed. 8) Mud detection The newly mixed mud shall be tested for viscosity and density once a day. The main technical indicators of the mud in the hole shall be measured for viscosity, density, sand content, water loss, etc. before concrete pouring. The mud replaced by concrete pouring must be treated by sedimentation or other purification methods before it can be reused.

[0047] 6. Casting of anti-seepage wall (concrete) The impermeable wall casting / construction can be carried out according to the existing technology.

[0048] Before pouring concrete, the anti-seepage wall steel grid should be laid out according to the design requirements, and the prefabricated steel grid should be hoisted into the groove used to construct the anti-seepage wall.

[0049] When pouring concrete, a mobile crane (such as a truck crane) can be used to lift the conduit. Workers hang the wire rope on the crane hook, then tie the wire rope to the conduit and fix it with a special rope clamp. A conduit is hoisted into place. According to the concrete pouring process, the conduit will be lifted and lowered many times. The crane should be commanded by a dedicated person to ensure the safety of the crane. According to the requirements for pouring concrete for anti-seepage walls, two conduits need to be hoisted for each warehouse to pour concrete.

[0050] In order to effectively solve the problem that the connection of the conduit in the above construction method is time-consuming and labor-intensive, which affects the efficiency of conduit hoisting, especially when the construction site is small and the mobile crane does not meet the construction requirements, a fixed anti-seepage wall concrete pouring conduit lifting device can be used. This device is simple to manufacture, easy to install, and easy to operate. It has the advantages of fewer construction workers, convenient operation, high work efficiency, and is more economical than a car crane, which effectively ensures the safety of engineering construction.

[0051] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present invention can be arbitrarily combined to form several different specific implementation methods.

Claims

1. A method for constructing an underground anti-seepage wall without disturbing surrounding existing structures, characterized in that Before construction, geological re-exploration is carried out in relevant areas, and the geological status of the corresponding areas is obtained based on the analysis of the re-exploration results. The impact of the geological conditions of each part on the construction of the cut-off wall and the cut-off wall is analyzed and determined. Treatment measures are adopted for the unfavorable geology that affects the construction of the cut-off wall and / or the cut-off wall to eliminate the impact of the unfavorable geology on the construction of the cut-off wall and the cut-off wall; or, based on the unfavorable geology that affects the construction of the cut-off wall and / or the cut-off wall, the design plan of the cut-off wall is modified to avoid the impact of the unfavorable geology on the construction of the cut-off wall and the cut-off wall.

2. The underground cut-off wall construction method without disturbing surrounding existing structures as claimed in claim 1, characterized in that The geological re-exploration is carried out by using natural source surface wave advance detection technology.

3. The underground cut-off wall construction method without disturbing surrounding existing structures as claimed in claim 2, characterized in that The geological re-exploration is carried out using micro-motion B-ultrasound technology.

4. The underground cut-off wall construction method without disturbing surrounding existing structures as claimed in claim 3, characterized in that When implementing geological re-exploration, parallel survey lines or grid survey lines are used to construct a survey network.

5. The underground cut-off wall construction method without disturbing surrounding existing structures as claimed in claim 1, characterized in that The geological conditions include the conditions of existing underground structures and the surrounding media conditions.

6. The method for constructing an underground cut-off wall without disturbing surrounding existing structures according to any one of claims 1 to 5, characterized in that Determine the impact on the construction and construction of the cut-off wall based on the characteristics of the adverse geology and the scope of the area where it is located.

7. The method for constructing an underground cut-off wall without disturbing surrounding existing structures as claimed in any one of claims 1 to 5, characterized in that When the cut-off wall overlaps with an existing underground structure, it is preferred to modify the cut-off wall design.

8. The method for constructing an underground cut-off wall without disturbing surrounding existing structures according to any one of claims 1 to 5, characterized in that When adverse geology affects the construction of the cut-off wall or the cut-off wall is not suitable and / or difficult to effectively treat, it is preferred to modify the cut-off wall design.

9. The method for constructing an underground cut-off wall without disturbing surrounding existing structures according to any one of claims 1 to 8, characterized in that During the construction of drilling holes in the anti-seepage wall, a grab bucket is used to grab the upper covering layer, and a rotary drilling rig is used to drill and split the bottom bedrock into grooves.

10. The method for constructing an underground cut-off wall without disturbing surrounding existing structures according to any one of claims 1 to 8, characterized in that The drilling and splitting method is used to make holes and grooves on the bedrock. After the grooves extend to the bedrock, the main hole positions are set alternately. The auxiliary hole positions are between adjacent main holes. The adjacent edge parts between the auxiliary holes and the adjacent main holes overlap. After the main holes on both sides of the auxiliary holes are completed, the auxiliary holes are drilled and split.

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