Undisturbed foundation trench hydraulic excavation slag removal device and technology

Abstract

The device mainly comprises a high-pressure cutting assembly and a vacuum slag suction assembly, the high-pressure cutting assembly comprises a high-pressure cutting water gun and a high-pressure pump connected with a background, the high-pressure pump outputs high-pressure jet water flow to cut a soil layer, and crushed sludge is deposited to the bottom of a groove; the vacuum slag suction assembly comprises a vacuum suction pump and a connected sludge suction pump pipe, the sludge suction pump pipe is vertically arranged at the bottom of the foundation trench, sludge which is dispersed to the bottom of the trench through hydraulic force can be immediately sucked away and conveyed to the settling tank through a pipeline for secondary treatment, and clear water separated from the settling tank can be recycled to a high-pressure pump for recycling. And the precipitated slurry is transported outwards by a closed container or is transported outwards by dry soil after further dehydration. According to the technology, the foundation trench section conforming to the set shape is excavated through cyclic operation of hydraulic cutting, trench bottom precipitation and vacuum suction removal, compared with traditional mechanical excavation, disturbance-free hydraulic cutting excavation is adopted in the technology, the excavation range can be accurately controlled, interference to the surrounding environment is extremely small, the risk of violent accidental injury to original underground infrastructures is greatly reduced, and the construction efficiency is improved. The method is particularly suitable for being implemented in a complex environment with densely-distributed pipe networks, and is an efficient and safe non-destructive excavation method.

Description

Technical Field

[0001] This invention relates to the excavation and cleaning of foundation trenches for building structures, specifically belonging to the field of foundation trench excavation and cleaning construction, and is applicable to non-destructive foundation trench construction scenarios in environments with dense underground facilities. Background Technology

[0002] In complex environments with dense pipe networks, various high-pressure gas pipes, fiber optic cables, electrical cables, water supply pipes, and other pipelines are often intricately buried underground. Currently, the mainstream trench excavation technology in the industry mainly relies on mechanical excavation and manual excavation, which has significant technical shortcomings and application limitations.

[0003] While mechanical excavation (such as excavators and hydraulic breakers) is highly efficient, it has low excavation accuracy. Especially in urban old districts and commercial areas with dense underground pipelines (water supply, drainage, gas, and communication cables), mechanical operation errors can easily damage underground structures, causing pipeline leaks, communication interruptions, and other accidents. Subsequent repair costs are high and seriously affect the lives of citizens. At the same time, mechanical operations can severely disturb the surrounding soil layers, which may lead to road subsidence, cracking of nearby buildings, and strong environmental interference.

[0004] While manual excavation can reduce the risk of accidental injury to structures, it is labor-intensive and extremely inefficient, and is only suitable for shallow trenches and small-scale operations, which cannot meet the time requirements of large-scale projects. Moreover, when excavating deep trenches manually, there are prominent safety hazards such as soil collapse, and the safety of the operation is difficult to guarantee.

[0005] Furthermore, some projects have attempted simple hydraulic excavation (using only high-pressure water to cut through the soil layers), but lack a supporting efficient slag removal system. The accumulation of slag at the bottom of the trench hinders subsequent excavation, and water resources cannot be recycled, resulting in waste. Simultaneously, the indiscriminate transportation of slag can easily cause road pollution, failing to meet environmental protection construction requirements. In summary, existing processes struggle to balance the three-dimensional requirements of "safety, accuracy, efficiency, and environmental protection," especially exhibiting poor applicability in complex and sensitive environments. Therefore, a trench excavation and slag removal technology that balances safety, efficiency, and environmental protection is urgently needed. Summary of the Invention

[0006] This invention aims to address the technical pain points of existing trench excavation and slag removal processes, such as low precision of mechanical excavation, easy damage to underground infrastructure and disturbance to the surrounding environment, low efficiency and high safety hazards of manual excavation, and lack of supporting slag removal and water circulation systems for simple hydraulic excavation. The invention provides a undisturbed trench hydraulic excavation and slag removal device and process that takes into account safety, efficiency and environmental protection.

[0007] I. Device Composition The core of this invention's device includes a high-pressure cutting assembly and a vacuum slag suction assembly, which work together to achieve an integrated "cutting-slag removal-disposal" operation. The high-pressure cutting assembly consists of a high-pressure cutting water gun, a connecting hose, and a high-pressure pump. The high-pressure pump is connected to the high-pressure cutting water gun via the connecting hose, providing power for cutting the soil layer in the trench. The vacuum slag suction assembly includes a vacuum slag suction pump pipe, a conveying pipe, and a sedimentation tank. The vacuum slag suction pump pipe is vertically inserted into the bottom of the trench to adsorb slag from the bottom. The conveying pipe transports the adsorbed slag to the sedimentation tank, which serves as a secondary treatment unit, handling slag separation and water recovery. Simultaneously, the high-pressure pump has a pressure regulation function, allowing for flexible adjustment of the jet water pressure according to the hardness of the excavated soil layer, ensuring cutting effectiveness under different geological conditions. The placement of the vacuum slag suction pump pipe is adapted to the cutting position of the high-pressure cutting water gun, and the suction port is lower than the cutting position, ensuring sufficient slag adsorption and preventing accumulation at the bottom of the trench.

[0008] II. Process Steps The process of this invention achieves trench excavation through a cyclical operation of "high-pressure water jet cutting - bottom sedimentation - vacuum suction". The specific steps are as follows: Step 1: Start the high-pressure cutting assembly. The high-pressure pump in the background delivers high-pressure jet water to the high-pressure cutting water gun through the connecting hose. The water jet impact force cuts the soil layer in the foundation trench, breaking the soil layer into mud. The broken mud is naturally deposited to the bottom of the foundation trench under the action of gravity. Step 2: Insert a negative pressure vacuum sludge suction pump pipe at the corresponding position at the bottom of the foundation trench, turn on the vacuum suction pump, and quickly suck up the sludge deposited at the bottom of the trench through the sludge suction pump pipe; Step 3: The sucked-in sludge is transported to the sedimentation tank through the conveying pipe. The sedimentation tank performs secondary treatment on the sludge, separating the slurry and clear water through sedimentation. The separated clear water can be recycled to the high-pressure pump for reuse, while the sedimented sludge is transported off-site in a sealed container or transported off-site as dry soil after further dehydration treatment to avoid environmental pollution.

[0009] By repeatedly performing the above three steps, a foundation trench section that meets the predetermined shape requirements can be gradually excavated. Beneficial effects

[0010] Compared with existing processes, this invention has significant advantages: First, it adopts a non-disruptive hydraulic cutting method, and the high-pressure jet water flow can precisely control the cutting range, effectively reducing disturbance to the surrounding soil layers and greatly reducing the risk of violent damage to underground cables, pipelines and other infrastructure. It is especially suitable for complex environments such as old urban areas and commercial districts with dense pipe networks. Second, the "cutting-slag removal" is carried out simultaneously, which greatly improves efficiency compared to manual excavation and eliminates the need for frequent movement of large equipment, making the operation more flexible. Third, the sedimentation tank enables the recycling of clean water, reducing water waste. At the same time, the mud is transported in a closed manner or dehydrated, which meets the requirements of environmentally friendly construction and avoids the pollution of roads and the environment caused by the random discharge of mud. It is a non-destructive excavation technology that combines safety, efficiency and environmental protection. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of the undisturbed trench hydraulic excavation and slag removal device of the present invention, which is used to clearly show the structural composition of the device, the connection relationship of each component and the working status. The device and working process will be described in detail below with reference to this figure.

[0012] I. Overall Structure of the Device The core of this device consists of two major functional components: a high-pressure cutting component (1) and a vacuum slag suction component (2). The two work together to complete the excavation and slag removal of the foundation trench soil layer, and also involve the relevant foundation trench soil layer (3), the foundation trench cross section (5) formed after excavation, and underground structures such as existing underground cables (41) and underground pipelines (42) that need to be avoided.

[0013] II. Structure and Function of Each Component (a) High-pressure cutting assembly (1) The high-pressure cutting assembly (1) provides power for soil cutting and includes a high-pressure cutting water gun (11), a connecting hose (12), and a high-pressure pump (13) connected to the back end.

[0014] Component connection relationship: The high pressure pump (13) is connected to the high pressure cutting water gun (11) through the connecting hose (12) to form a high pressure water flow delivery channel; the high pressure cutting water gun (11) has a nozzle (111) at the lower end, which is the spray outlet of the high pressure water flow.

[0015] Working function: After the high pressure pump (13) is started, the high pressure water flow is delivered to the high pressure cutting water gun (11) through the connecting hose (12), and the high pressure jet water flow (112) is output from the nozzle (111); the high pressure jet water flow (112) acts on the soil layer (3) of the foundation trench with strong impact force, thereby cutting and breaking the soil layer. The mud (31) formed after breaking is naturally deposited to the bottom of the foundation trench under the action of gravity.

[0016] (ii) Vacuum slag suction assembly (2) The vacuum sludge suction assembly (2) is responsible for the removal and subsequent treatment of sludge at the bottom of the tank. It includes a vacuum sludge suction pump pipe (21), a conveying pipe (22), and a sedimentation tank (23).

[0017] Component connection relationship: The vacuum suction pump pipe (21) is a mud suction component, and the two ends of the conveying pipe (22) are connected to the vacuum suction pump pipe (21) and the sedimentation tank (23) respectively, forming a mud conveying channel.

[0018] Working function: The vacuum sludge pump pipe (21) needs to be vertically inserted into the bottom of the soil layer (3) of the foundation trench, and can immediately adsorb the sludge (31) deposited at the bottom of the trench; the adsorbed sludge (31) is transported to the sedimentation tank (23) through the conveying pipe (22), and the sedimentation tank (23) performs secondary treatment on the sludge, separating the clear water and sludge through sedimentation. The separated clear water can be recycled back to the high-pressure pump (13) to realize the recycling of water resources; the sludge after sedimentation is transported out in a closed container, or transported out in the form of dry soil after further dehydration treatment to avoid environmental pollution.

[0019] III. Working Process and Technological Advantages Work process: When the device is running, the trench is excavated by the cycle of "high pressure water jet cutting - bottom sedimentation - vacuum suction". First, the high pressure cutting component (1) cuts the soil layer to produce mud (31). After the mud is deposited, it is promptly removed and disposed of by the vacuum suction component (2). The cycle is repeated until the trench section (5) that meets the predetermined shape requirements is excavated.

[0020] Operational precautions and technical advantages: During the hydraulic excavation and slag removal process, it is necessary to control the operating position of the high-pressure pump (13) and the high-pressure cutting water gun (11) and appropriately avoid existing underground cables (41), underground pipelines (42) or other underground structures. This device adopts a high-pressure water jet non-disturbance excavation method. Compared with traditional mechanical excavation, it will not cause physical damage to existing underground structures during the operation. This is the core technical advantage of this process, which can effectively ensure the safety of underground infrastructure. Detailed Implementation

[0021] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0022] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention. The invention will now be described in detail with reference to the accompanying drawings.

[0023] The specific implementation of this invention needs to be combined with the on-site environment and device characteristics, and carried out according to the "preparation-operation-monitoring" process. The following are the detailed implementation steps.

[0024] I. On-site preparation stage First, a site survey was conducted. Existing underground cables, pipes, and other structures were located using an underground pipeline detector and marked on the construction drawings to clarify the obstacle avoidance range of the high-pressure cutting components. Next, the device components were inspected: the power systems of the high-pressure pump and vacuum suction pump were confirmed to be normal; the connecting hoses and delivery pipes were free of damage and leaks; the nozzles of the high-pressure cutting water gun were not blocked; and the filter screen inside the sedimentation tank was clean. Finally, the equipment was arranged, placing the high-pressure pump and sedimentation tank in a flat area at the edge of the trench (at least 1.5m from the edge to avoid affecting operations). The high-pressure pump and high-pressure cutting water gun were connected via connecting hoses, and the vacuum sludge suction pump pipe was connected to the sedimentation tank via a delivery pipe, completing the assembly and commissioning of the device.

[0025] II. Core Operating Procedures The operation is structured as a cycle unit consisting of "high-pressure water jet cutting - bottom sedimentation - vacuum removal", as detailed below: 1. Cutting operation: Start the high-pressure pump and adjust the pressure according to the softness or hardness of the soil layer in the trench (the pressure can be appropriately reduced for soft soil and increased for hard soil). The high-pressure water flows through the connecting hose and sprays out from the nozzle of the water gun. The operator holds the high-pressure cutting water gun and cuts the soil layer from top to bottom along the design line of the trench section. The cutting width is controlled within ±5cm of the design value. The broken mud and debris naturally settle to the bottom of the trench. 2. Slag removal operation: After the slag generated in the cutting area has settled, the vacuum slag suction pump pipe is vertically placed into the bottom of the tank, ensuring that the suction port is 5-10cm lower than the cutting position. The vacuum suction pump is started, and the slag at the bottom of the tank is sucked in through the slag suction pump pipe. The slag is then conveyed into the sedimentation tank through the conveying pipe. 3. Sludge Treatment: The sludge in the sedimentation tank is allowed to settle, and the clear water is collected at the bottom of the tank through a filter. The recovery valve is then opened to return the clear water to the high-pressure pump for recycling. When the sludge in the sedimentation tank reaches 2 / 3 of its volume, the suction pump is turned off, and the sludge is transported in a sealed tanker truck, or dewatered into dry soil using a dewatering machine before being transported off-site. This cycle is repeated, gradually excavating to the designed depth to form a foundation trench cross-section that meets the requirements.

[0026] III. Operational Monitoring and Precautions During the operation, dedicated personnel monitored the process in real time: first, observing the position of the high-pressure water jet cutting gun to ensure it avoided underground structures; second, checking the stability of the trench walls, and immediately suspending cutting and implementing support measures if a risk of local collapse occurred; and third, monitoring the clean water recovery rate in the sedimentation tank to ensure efficient water resource recycling. Additionally, after every three cycles, the cross-sectional dimensions of the trench were measured, and the cutting trajectory was adjusted promptly to ensure excavation accuracy.

[0027] IV. Implementation Results Verification After excavation is completed, check the cross-sectional dimensions of the foundation trench (≤±10mm), inspect the underground structures for integrity, and after confirming that there is no damage, clean up the residual mud at the bottom of the trench to complete the foundation trench excavation. Example

[0028] I. Project Background This case study involves the renovation of streetlights on a main urban road. It requires the construction of 200 new cast-in-place concrete foundations for streetlight poles, each with a trench dimension of 0.8m (length) × 0.8m (width) × 1.2m (depth). The project route runs along an old city commercial street with a dense underground network of 10kV power cables, fiber optic cables, and DN100-DN200 water supply pipelines. The core requirement is to employ a undisturbed hydraulic excavation and slag removal process to ensure zero damage to existing underground pipelines and cables, while simultaneously guaranteeing excavation efficiency and construction safety for the 200 foundations.

[0029] II. Preliminary Preparations 1. Precise pipeline location: In conjunction with municipal, power, and telecommunications departments, we obtain underground pipeline maps along the route and use the RD8000 underground pipeline detector to conduct on-site re-measurement of each basic point, marking the pipeline location (such as communication optical cables at 0.5-0.8m from the ground surface and water supply pipelines at 1.0-1.3m). We then mark the "no-cutting zone" on the ground with colored spray paint to ensure that the working range of the high-pressure cutting components is ≥30cm away from the pipeline.

[0030] 2. Equipment adaptation and adjustment: Select miniaturized equipment to adapt to the narrow working space of 0.8m×0.8m - the high-pressure cutting water gun adopts a handheld small gun body (gun head diameter ≤5cm), the vacuum mud suction pump pipe adopts a rigid pipe with a diameter of 80mm (for easy flexible movement in the trench), and the high-pressure pump adopts a 3kW small portable pump (pressure adjustment range 10-20MPa, suitable for shallow trench soil layer cutting).

[0031] 3. Specialized training for personnel: Specialized training will be conducted for operators, focusing on the techniques for shallow trench cutting of street light foundations (avoiding over-excavation) and key points for pipeline obstacle avoidance operations (stopping the machine immediately if pipeline signal fluctuations are encountered). Three simulated foundation excavation practical assessments will be conducted, and only those who pass the assessments can be allowed to work.

[0032] III. Core Implementation Process (Single Foundation Excavation) 1. Cutting operation: The operator holds a high-pressure cutting water gun and cuts from the edge of the trench to the center in 4 areas. The pressure is adjusted according to the hardness of the soil layer (12MPa for silty clay and 18MPa for clay layer). Cutting is done layer by layer from top to bottom (each layer is cut to a depth of 20cm to avoid trench wall collapse). The cutting trajectory strictly follows the 0.8m×0.8m boundary. The broken mud and debris are naturally deposited at the bottom of the trench.

[0033] 2. Sludge removal operation: After each layer is cut, wait for the sludge to settle, then vertically place the flexible sludge suction pump pipe into the bottom of the tank (the suction port is 5cm below the cutting surface), start the vacuum suction pump, and slowly move the sludge suction pipe along the bottom of the tank to ensure that all the sludge in the 0.8m×0.8m range is removed (the sludge removal time is about 3 minutes per cycle). The sludge is then sent to the mobile sedimentation tank through the conveying pipe.

[0034] 3. Cyclic operation and depth control: Repeat the "layer cutting - layer cleaning" process. After every 3 layers (60cm depth), use a steel tape measure to measure the trench depth and dimensions to ensure no over-excavation (dimensional deviation ≤ ±5mm). When excavating to a depth of 1.0m (close to the water supply pipeline), reduce the cutting pressure to 10MPa and use the "point cutting method" (cutting small areas point by point). At the same time, observe the position of the pipeline below the trench wall to ensure safe excavation to the designed depth of 1.2m.

[0035] IV. Batch Implementation Control and Results 1. Batch Excavation Strategy: Divide the 200 foundations into 20 groups (10 foundations per group) according to road sections. Each group is equipped with 1 set of equipment and 2 operators. Complete the excavation of 40 foundations per day (including equipment transfer time) and complete all excavation work in 5 days. This avoids continuous disturbance to underground pipelines caused by concentrated construction in the same area.

[0036] 2. Quality and safety control: Each group is equipped with one full-time safety officer to monitor the pipeline detector signal in real time (stop immediately if any abnormality is found) and check the stability of the trench wall (lay plastic film in time to prevent collapse of loose soil layers); after all foundation excavation is completed, check the integrity of underground pipelines in each trench and check the dimensions of the foundation trench (0.8m×0.8m×1.2m deviation ≤±5mm).

[0037] 3. Implementation Results: No underground cables or pipelines were damaged during the excavation of the foundation trenches for 200 streetlights. The water recycling rate reached 85% (the water consumption per foundation was only 0.3m³, which is 60% less than that of traditional hydraulic excavation). The excavation time for a single foundation was controlled within 40 minutes, which met the project schedule requirements and laid a safe foundation for the subsequent cast-in-place concrete foundation construction.

[0038] This invention patent has significant advantages: First, it employs undisturbed hydraulic cutting, coupled with an adjustable pressure high-pressure pump suitable for different soil layers, enabling precise control of the excavation range and significantly reducing the risk of accidental damage to underground cables, pipelines, and other infrastructure, especially suitable for environments with dense pipe networks; Second, the "hydraulic cutting-bottom sedimentation-vacuum removal" cyclic operation, combined with the reasonable layout of the sludge suction pump pipe, can efficiently remove slag and ensure a regular trench cross-section; Third, the sedimentation tank realizes the recycling of clean water, saving water resources, and the sedimented sludge is transported off-site in a closed manner or dehydrated to avoid environmental pollution; The overall process takes into account safety, efficiency, and environmental protection, solving the problems of disturbance, inefficiency, and pollution of traditional excavation.

[0039] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A device and process for undisturbed hydraulic excavation and slag removal in foundation trenches, characterized in that, It includes a high-pressure cutting assembly and a vacuum slag suction assembly; the high-pressure cutting assembly includes a high-pressure cutting water gun and a high-pressure pump connected to the back end via a hose, the high-pressure pump can provide high-pressure jet water to the high-pressure cutting water gun to cut the soil layer of the foundation trench; the vacuum slag suction assembly includes a vacuum sludge suction pump pipe, a conveying pipe and a sedimentation tank, the sludge suction pump pipe is vertically placed at the bottom of the foundation trench, the vacuum sludge suction pump pipe sucks up the sludge at the bottom of the trench and transports it to the sedimentation tank through the pipeline for secondary treatment.

2. The undisturbed hydraulic trench excavation and slag removal device and process according to claim 1, characterized in that, Includes the following steps: Step 1: Using a high-pressure cutting water gun, a high-pressure water jet is output from a high-pressure pump to cut the soil layer, causing the broken mud to settle at the bottom of the trench. Step 2: A negative pressure vacuum mud suction pump pipe is placed at the bottom of the trench, and the mud at the bottom of the trench is sucked in by the vacuum suction pump. Step 3: The sucked mud is transported through pipelines to a sedimentation tank for secondary treatment.

3. The undisturbed hydraulic trench excavation and slag removal device and process according to claim 1, characterized in that, The high-pressure water jet pressure provided by the high-pressure pump can be adjusted according to the hardness of the excavated soil layer to meet the cutting requirements of different soil layers.

4. The undisturbed hydraulic trench excavation and slag removal device and process according to claim 2, characterized in that, The insertion position of the negative pressure vacuum sludge suction pump pipe in step two is adapted to the cutting position of the high-pressure cutting water gun, and the sludge suction port position is lower than the cutting position.

5. The undisturbed hydraulic trench excavation and slag removal device and process according to claim 1, characterized in that, The secondary treatment of sludge in the sedimentation tank includes: sedimentation to separate sludge from water. The separated water can be recycled to a high-pressure pump for reuse. The sedimented sludge can be transported out through a sealed container or dehydrated and then transported out as dry soil.

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