Method for detecting leakage of plastic concrete diaphragm wall
By demarcating weak areas in plastic concrete anti-seepage walls, scientifically arranging holes, and combining multiple detection methods, the problems of detection accuracy and cost limitations in existing technologies are solved, and efficient and accurate leakage point detection and repair are achieved. It is suitable for anti-seepage wall detection in complex strata.
Patent Information
- Application Number
- CN202511061912.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-31
- Publication Date
- 2025-09-30
AI Technical Summary
Existing technologies for detecting leakage in plastic concrete anti-seepage walls are limited in accuracy and cost, making it difficult to detect leakage points efficiently and accurately and potentially causing damage to the wall.
Through comprehensive analysis to identify weak areas, scientifically arrange hole positions, accurately drill holes and conduct water injection experiments, combined with resistivity imaging, electromagnetic wave tomography and flow meter monitoring, leakage points are systematically detected, and the wall is protected from serious damage during the detection process.
It realizes efficient and accurate detection of leakage points of plastic concrete anti-seepage walls, and is suitable for leakage detection and repair of anti-seepage walls under complex strata, avoiding serious damage to the wall.
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of concrete anti-seepage, and particularly relates to a method for detecting leakage of a plastic concrete anti-seepage wall. Background Art
[0002] Plastic concrete cut-off walls are widely used in underground anti-seepage projects due to their excellent anti-seepage properties, low construction costs, and good seismic and crack resistance. However, due to complex geological conditions, the quality of cut-off wall construction is difficult to guarantee, and wall leakage is a common problem. Existing leak detection technologies, such as resistivity imaging, electromagnetic tomography, flow velocity measurement, and pigment reagent methods, can detect leaks to a certain extent, but due to limitations in accuracy, depth, and cost, the detection results are less than ideal. Summary of the Invention
[0003] The purpose of the present invention is to provide a method for detecting leakage of a plastic concrete anti-seepage wall, which can efficiently and accurately detect the leakage point of the plastic concrete anti-seepage wall and does not cause serious damage to the wall during the detection process.
[0004] The technical solution of the present invention is as follows: A method for detecting leakage of a plastic concrete anti-seepage wall comprises the following steps:
[0005] Step 1: Check for leaks;
[0006] Step 2: hole arrangement;
[0007] Step 3: Drilling rig in place;
[0008] Step 4: Drilling and recording;
[0009] Step 5: Clean the hole;
[0010] Step 6: Water injection experiment;
[0011] Step 7: Data analysis and abnormal hole processing.
[0012] In the above-mentioned step 1, a comprehensive analysis is first conducted to delineate weak areas. The analysis is conducted in combination with the quality control details of the construction process, self-inspection and self-correction records, settlement and displacement monitoring data, trenching records and geological survey reports. The wall quality directly affects the anti-seepage performance. The long concrete interval during the construction process affects the bonding of new and old concrete, and the cold joints that may be formed are easy to become water channels; the conduit falls off or is not buried deep enough during concrete segregation or pouring, which can easily lead to mud inclusion and looseness in the concrete; the mud is not cleaned cleanly during the construction of the trench joint, which can easily lead to loose wall connections; the wall inclination is too large, resulting in a reduction in the wall thickness at the junction of adjacent trench sections; excessive local settlement and displacement can easily cause wall cracks; there may be misjudgment when trenching the geological mutation position of the impermeable layer at the bottom of the wall, or the bottom of the adjacent trench joint is not deep enough into the stratum required by the design. Areas with the above problems are all regarded as weak areas of the wall.
[0013] In the step 2, the leak detection holes are arranged on the axis of the anti-seepage wall, and the hole center is allowed to deviate by 50 mm. The slot section joints are the weak parts of the anti-seepage wall, and the holes are arranged first. The drilling plan is arranged in the order of Ⅰ-Ⅲ-Ⅱ-Ⅲ-Ⅰ. First, the sequence I holes are arranged with three joints at intervals of about 20 m; the joints between adjacent sequence I holes are sequence II holes, and the remaining joints are sequence III holes. The sequence I holes are constructed first, followed by sequence II, and finally the sequence III holes. If no leakage point is found after all three sequences are completed, the holes are continued to be arranged in the middle of adjacent holes.
[0014] In step 3, the construction site is cleaned to ensure that the drilling rig is placed stably and firmly. After the drilling rig is in place, the horizontality of the drilling rig is measured with a spirit level, and the verticality of the drill rod and drilling tool is measured by a total station or theodolite. The deviation is no more than 5‰. After the horizontality of the pile driver and the verticality of the drill rod meet the standards, the drill bit position is fine-tuned so that its apex corresponds to the hole position.
[0015] In step 4, the upper limit of the slope is calculated based on the actual slope of the wall, the position of the leak detection hole, the wall thickness and the drilling depth, and 50% of this value is used as the verticality control parameter to prevent the drill hole from penetrating the wall and affecting the leakage judgment.
[0016] In step 5, the hole is cleaned immediately after the drilling is completed to prevent the wall mud or sediment from temporarily blocking the seepage cracks, and water is added to circulate the hole until the hole wall mud is basically cleaned.
[0017] In step 6, fill the hole with water, mark the hole mouth, and observe and record the distance from the water surface in the hole to the mark every 5 minutes. The total observation time is generally 1 hour. If the water level drops rapidly, the water level continues to drop visibly after water filling, and drops by more than 5 cm per minute, then shorten the observation time interval.
[0018] After the leak detection holes in step 7 are completed, they are promptly sealed and protected to prevent foreign matter from falling in. All completed leak detection holes are marked on the drawing, with emphasis on abnormal holes. On the plan layout of the leak detection holes on the anti-seepage wall, a seepage change trend diagram is drawn based on the seepage velocity of each hole.
[0019] The beneficial effects of the present invention are: through comprehensive analysis to delineate weak areas, scientifically arrange hole positions, accurately drill holes and analyze data, it is possible to efficiently and accurately detect leakage points of plastic concrete anti-seepage walls without causing serious damage to the wall during the detection process. It is suitable for leakage detection and repair of anti-seepage walls under complex strata. DETAILED DESCRIPTION
[0020] The present invention is further described in detail below with reference to specific embodiments.
[0021] The present invention provides a method for detecting leakage of a plastic concrete anti-seepage wall, which is combined with strong drainage and is suitable for leakage detection of anti-seepage walls under complex strata.
[0022] A method for detecting leakage in plastic concrete cutoff walls begins with a comprehensive analysis to delineate weak areas. This method then systematically checks for leaks through procedures such as hole placement, drilling rig positioning and drilling records, hole cleaning and water injection testing, as well as data analysis and abnormal hole handling. Each step ensures data accuracy and validity, particularly in the delineation of weak areas and hole placement, which emphasize precise measurements and detailed records.
[0023] The equipment used in the leak detection process includes resistivity imaging equipment, electromagnetic tomography (CT) equipment, flowmeters, and water injection test equipment. These devices are used to detect differences in the conductivity of the underground medium, infer the distribution of the medium's attenuation coefficient, monitor the speed and direction of underwater undercurrents near the anti-seepage wall, and determine the leakage situation by observing water level changes through water injection experiments.
[0024] The leak detection process begins with a comprehensive analysis of the common causes of leakage in the cut-off wall, and combines self-inspection and self-correction with the details of construction quality control, marking the prominent parts of the cut-off wall deformation, and analyzing the weak points of the wall. Subsequently, the leak detection holes are arranged on the axis of the cut-off wall, with priority given to the weak links such as the slot joints. After the drilling rig is in place, the construction site needs to be cleaned, the horizontality of the drilling rig and the verticality of the drill rod must be ensured, and the construction process and data of each leak detection hole must be recorded in detail. After the drilling is completed, the hole is immediately cleaned and a water injection test is carried out to observe and record the changes in the water level in the hole to determine the leakage situation. Finally, the water injection test data is analyzed, a seepage change trend chart is drawn, abnormal holes are marked, and the hole layout plan is adjusted in a timely manner to improve the efficiency of leak detection.
[0025] The present invention provides a combined drainage and drilling leak detection method. In this example, the process of leak detection in the vertical plastic concrete cutoff wall of the sodium-cooled fast reactor water intake cofferdam is described in detail. The wall has a total length of 1,352 meters, a top elevation of +5.0 meters, a width of 0.8 meters, and a bottom that extends no less than 2 meters into the impermeable layer.
[0026] A method for detecting leakage of a plastic concrete anti-seepage wall comprises the following steps:
[0027] Step 1: Check for leaks
[0028] First, a comprehensive analysis is conducted to delineate weak areas. Analysis is conducted based on construction process quality control details, self-inspection and self-correction records, settlement and displacement monitoring data, trenching records, and geological survey reports. Wall quality directly affects anti-seepage performance. For example, if the interval between concrete fillings during construction is too long, it will affect the bonding between new and old concrete, and the cold joints that may form can easily become water channels. Concrete segregation or the detachment of conduits during pouring or insufficient burial depth can easily lead to mud inclusions and loose concrete. Failure to clean the mud during trench joint construction can easily lead to loose wall connections. Excessive wall inclination can reduce the wall thickness at the junction of adjacent trench sections. Excessive local settlement and displacement can easily cause wall cracking. Trenching at the location of a sudden change in the geological aquifer at the bottom of the wall, which is not (weakly) permeable, may result in misjudgment, or the bottom of the adjacent trench joints may not penetrate the stratum to the required depth as designed. Areas with these problems can be considered weak areas in the wall.
[0029] Step 2: Hole Arrangement
[0030] Leak detection holes are placed on the axis of the anti-seepage wall, with a tolerance of 50mm for hole centering. Slot joints are weak points in the anti-seepage wall and are therefore prioritized for drilling. Drilling plans follow a I-III-II-III-I sequence. First, drill I holes every three joints, approximately 20m apart. The joint between adjacent I holes becomes a II hole, and the remaining joints become III holes. Drill I holes first, followed by II, and finally III. If no leaks are found after completing all three sequences, continue drilling between adjacent holes.
[0031] Step 3: Drilling Rig in Place
[0032] First, clean the construction site and ensure the drilling rig is positioned steadily and securely. Once the drilling rig is in place, measure its levelness with a spirit level. Measure the verticality of the drill rod and drill bit using a total station or theodolite, with a deviation of no more than 5‰. Once the pile driver's levelness and drill rod verticality meet the standards, fine-tune the drill bit position so that its apex aligns with the hole location.
[0033] Step 4: Drilling and Recording
[0034] Strictly control the verticality of the drill hole. Calculate the upper limit of the slope based on the actual wall slope, the location of the leak detection hole, the wall thickness, and the drill depth. Use 50% of this value as the verticality control parameter to prevent the drill hole from protruding through the wall and affecting leakage detection. Drill to the bedrock to verify the connection between the wall and the bedrock. Detailed records should be kept for each leak detection hole, including hole number, location, water injection test data, special circumstances, and treatment measures.
[0035] Step 5: Cleaning the Hole
[0036] Clean the hole immediately after drilling to prevent the retaining mud or sediment from temporarily blocking the water seepage cracks. Add water and circulate the hole until the mud on the hole wall is basically cleared.
[0037] Step 6: Water injection test
[0038] Fill the hole with water, mark the hole, and observe and record the distance from the water surface to the mark every 5 minutes. The total observation time is generally 1 hour. If the water level drops rapidly after filling, and the water level continues to drop visibly after filling, dropping by more than 5 cm per minute, shorten the observation interval.
[0039] Step 7: Data analysis and abnormal hole processing
[0040] After completing the leak detection holes, promptly seal and protect them to prevent foreign objects from falling in. Mark all completed leak detection holes on the drawing, focusing on abnormal holes. On the plan layout of the leak detection holes in the anti-seepage wall, draw a seepage trend chart based on the seepage velocity of each hole. Based on the seepage velocity distribution, analyze the weak sections of the anti-seepage wall and the leakage distribution. Wall sections with high and relatively concentrated seepage velocities of leak detection holes are more likely to contain water channels. These areas can be identified as key areas for timely adjustment of the hole layout plan to improve leak detection efficiency.
[0041] Implementation Effect
[0042] Through a combination of intensive drainage and drilling for leaks, significant leaks were successfully discovered and sealed in the anti-seepage walls of the East and West Intake Dikes. With timely plugging, precipitation requirements were met. Drilling was particularly successful in identifying major leaks near the mountain. Based on the principle of hole placement, the impact of the leak was determined and effectively sealed.
Claims
1. A method for detecting leakage of a plastic concrete anti-seepage wall, characterized in that: The following steps are involved: Step 1: Check for leaks; Step 2: hole arrangement; Step 3: Drilling rig in place; Step 4: Drilling and recording; Step 5: Clean the hole; Step 6: Water injection experiment; Step 7: Data analysis and abnormal hole processing.
2. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In the above-mentioned step 1, a comprehensive analysis is first conducted to delineate weak areas. The analysis is conducted in combination with the quality control details of the construction process, self-inspection and self-correction records, settlement and displacement monitoring data, trenching records and geological survey reports. The wall quality directly affects the anti-seepage performance. The long concrete interval during the construction process affects the bonding of new and old concrete, and the cold joints that may be formed are easy to become water channels; the conduit falls off or is not buried deep enough during concrete segregation or pouring, which can easily lead to mud inclusion and looseness in the concrete; the mud is not cleaned cleanly during the construction of the trench joint, which can easily lead to loose wall connections; the wall inclination is too large, resulting in a reduction in the wall thickness at the junction of adjacent trench sections; excessive local settlement and displacement can easily cause wall cracks; there may be misjudgment when trenching the geological mutation position of the impermeable layer at the bottom of the wall, or the bottom of the adjacent trench joint is not deep enough into the stratum required by the design. Areas with the above problems are all regarded as weak areas of the wall.
3. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In the step 2, the leak detection holes are arranged on the axis of the anti-seepage wall, and the hole center is allowed to deviate by 50 mm. The slot section joints are the weak parts of the anti-seepage wall, and the holes are arranged first. The drilling plan is arranged in the order of Ⅰ-Ⅲ-Ⅱ-Ⅲ-Ⅰ. First, the sequence I holes are arranged with three joints at intervals of about 20 m; the joints between adjacent sequence I holes are sequence II holes, and the remaining joints are sequence III holes. The sequence I holes are constructed first, followed by sequence II, and finally the sequence III holes. If no leakage point is found after all three sequences are completed, the holes are continued to be arranged in the middle of adjacent holes.
4. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In step 3, the construction site is cleaned to ensure that the drilling rig is placed stably and firmly. After the drilling rig is in place, the horizontality of the drilling rig is measured with a spirit level, and the verticality of the drill rod and drilling tool is measured by a total station or theodolite. The deviation is no more than 5‰. After the horizontality of the pile driver and the verticality of the drill rod meet the standards, the drill bit position is fine-tuned so that its apex corresponds to the hole position.
5. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In step 4, the upper limit of the slope is calculated based on the actual slope of the wall, the position of the leak detection hole, the wall thickness and the drilling depth, and 50% of this value is used as the verticality control parameter to prevent the drill hole from penetrating the wall and affecting the leakage judgment.
6. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In step 5, the hole is cleaned immediately after the drilling is completed to prevent the wall mud or sediment from temporarily blocking the seepage cracks, and water is added to circulate the hole until the hole wall mud is basically cleaned.
7. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: In step 6, fill the hole with water, mark the hole mouth, and observe and record the distance from the water surface in the hole to the mark every 5 minutes. The total observation time is generally 1 hour. If the water level drops rapidly, the water level continues to drop visibly after water filling, and drops by more than 5 cm per minute, then shorten the observation time interval.
8. A method for detecting leakage of a plastic concrete anti-seepage wall according to claim 1, characterized in that: After the leak detection holes in step 7 are completed, they are promptly sealed and protected to prevent foreign matter from falling in. All completed leak detection holes are marked on the drawing, with emphasis on abnormal holes. On the plan layout of the leak detection holes on the anti-seepage wall, a seepage change trend diagram is drawn based on the seepage velocity of each hole.