Double-pipe wall intelligent pumping well structure close to fault and construction method thereof

Abstract

The application provides a double-pipe-wall intelligent well structure near a fault and a construction method thereof, and particularly relates to the technical field of underground water level control. The well structure comprises a well body and an intelligent pumping system. The well body adopts a double-pipe structure. The intelligent pumping system comprises an intelligent pumping pipe, a water level sensor, a flow rate sensor and a control system. The control system is arranged on the ground. The intelligent pumping pipe extends into the well body. The well provided by the application is configured with specific materials to adapt to the geological conditions near the fault, improve the dewatering effect and the stability of the well shaft, and particularly considers the discontinuity of the underground water distribution near the fault when designing the outer pipe structure, so that the effective control of the underground water level can be realized under the complex geological conditions of the fault, thereby reducing the engineering risk.

Description

TECHNICAL FIELD

[0001] The present invention relates to the technical field of groundwater level control, specifically to a double-pipe-wall intelligent pumping well structure near a fault and a construction method thereof. BACKGROUND

[0002] In geotechnical engineering, the presence of groundwater can cause foundation instability, ground subsidence, and seepage problems. The treatment of groundwater in fault zones has certain particularities, such as complex rock structure, diverse groundwater flow channels, and large changes in groundwater pressure. These characteristics make it difficult for traditional groundwater extraction methods to achieve effective water level control near faults, increasing the risk of construction. Therefore, groundwater level reduction technology is of great significance in geotechnical engineering.

[0003] Traditional methods for reducing groundwater include well-point method, dewatering curtain method, and groundwater cutoff wall method. The well-point method involves setting multiple well points for groundwater extraction. Although the well-point method can improve the efficiency of groundwater extraction, it still has difficulty achieving stable water level control near faults due to the complexity of groundwater flow channels and large changes in groundwater pressure. The dewatering curtain method involves setting a dewatering curtain for groundwater control. However, in the vicinity of faults, the setting and construction of the dewatering curtain are difficult, and long-term stability of water level control cannot be guaranteed. When geotechnical engineering is located near a fault, these traditional methods may have limited effectiveness because the rock and soil conditions and groundwater flow characteristics in the fault area are very different from those in ordinary areas.

[0004] In summary, the existing groundwater treatment methods have many limitations near faults and cannot meet the needs of engineering construction for groundwater level control. Therefore, it is necessary to develop a new double-pipe-wall intelligent pumping well structure near a fault and a construction method to achieve effective control of groundwater levels near fault areas and reduce engineering risks. SUMMARY

[0005] To overcome the shortcomings of the prior art and solve the problem that existing groundwater treatment methods have many limitations near faults and cannot meet the needs of construction for groundwater level control, the present invention provides a double-pipe-wall intelligent pumping well structure near a fault and a construction method thereof, with the specific technical solutions as follows:

[0006] The double-pipe-wall intelligent pumping well structure near a fault includes a pumping well body and an intelligent pumping system. The pumping well body is a double-pipe structure. The intelligent pumping system includes an intelligent pumping pipe, a water level sensor, a flow rate sensor, and a control system. The control system is set on the ground, and the intelligent pumping pipe extends into the interior of the pumping well body.

[0007] Preferably, the inner-outer double tube structure comprises an inner tube and an outer tube; a gap exists between the inner tube and the outer tube, and a plurality of inflatable capsules are arranged in the gap.

[0008] Preferably, the length of the inflatable capsule is 1.5 m, and the internal-external pressure difference of the inflatable capsule is 1.0 Mpa.

[0009] Preferably, the outer tube is sequentially divided into a water-stable section, a filter section and a filter pipe section from top to bottom.

[0010] Preferably, the water-stable section is made of clay balls; the clay balls have a clay particle content of not less than 65% of the total components, a sand content of less than 18% of the total components, a water content of less than 13% of the total components, and a dry density of greater than 2.0 g / cm 3 ;

[0011] Preferably, the filter section is made of filter material with a particle size of 0.5-2.5 cm, and 25%-35% of coarse sand is added and stirred uniformly.

[0012] Preferably, the filter pipe section is made of a bridge-type filter pipe with a thickness of 8 mm.

[0013] Further preferably, the water level sensor and the flow rate sensor are fixed to the inner side of the inner tube wall.

[0014] Further preferably, the intelligent pumping pipe, the water level sensor and the flow rate sensor are electrically connected to the control system.

[0015] Further preferably, a plurality of water inlets are formed in the inner tube wall of the filter pipe section of the outer tube.

[0016] Further preferably, the bottom of the pumping well body is sealed by PVC material.

[0017] A construction method of a double tube wall intelligent pumping well structure near a fault, specifically comprising the following steps:

[0018] S1. Geological exploration and evaluation

[0019] Before the engineering construction, the geological conditions around the fault are explored in detail, including rock type, rock structure and underground water flow characteristics; according to the exploration results of the geological conditions, the reduction demand of the underground water level in the construction scheme is evaluated;

[0020] S2. Design scheme and determination of pumping well position

[0021] According to the geological exploration results in S1 and the control demand of the underground water level, the position of the pumping well body and the configuration parameters of each component in the intelligent pumping system are determined, and the design scheme of the pumping well is obtained;

[0022] S3. Excavation of the wellbore and installation of the outer pipe

[0023] According to the design scheme in S2, the wellbore is excavated and the outer pipe is installed, and the outer pipe is sequentially provided with a filter pipe section, a filter material section and a water-resisting stable section from bottom to top;

[0024] S4. Installation and fixation of the inner pipe and sealing of the well bottom

[0025] The inner pipe is installed in the outer pipe, and a plurality of inflatable capsules are arranged in the gap between the inner pipe and the outer pipe at intervals, so as to prevent the deformation of the wellbore through the support performance and sealing effect of the inflatable capsules; finally, the well bottom of the pumping well is sealed with PVC material;

[0026] S5. Installation of the intelligent pumping system

[0027] The control system of the intelligent pumping system is installed on the ground, and the water level sensor and the flow rate sensor are installed on the inner side of the inner pipe wall, so as to monitor the underground water level and flow rate in real time, and the control system automatically adjusts the pumping amount according to the monitoring result;

[0028] S6. Construction monitoring and adjustment

[0029] During the whole process of engineering construction, the underground water level, flow rate and dewatering effect are continuously monitored; according to the monitoring result, the parameters of the intelligent pumping system are timely adjusted.

[0030] The beneficial effects of the present application are:

[0031] The present application has higher stability and good pumping effect, can reduce the engineering risk and improve the construction efficiency. At the same time, the present application fully considers the particularity of fault geological conditions in the construction process, ensures the safety and reliability of engineering construction, and reduces the difficulty and cost of engineering construction in the vicinity of the fault. BRIEF DESCRIPTION OF DRAWINGS

[0032] The drawings attached to the specification of the present application are used to provide further understanding of the present application and do not constitute an improper limitation on the present application.

[0033] Figure 1 It is a schematic diagram of the overall structure of the present application;

[0034] Figure 2 It is a schematic diagram of the outer pipe structure in the present application;

[0035] In the figure, 1 is the ground, 2 is the fault, 3 is the underground water level, 4 is the well bottom, 5 is the inner pipe, 6 is the outer pipe, 6-1 is the water-resisting stable section, 6-2 is the filter material section, 6-3 is the filter pipe section, 7 is the inflatable capsule, 8 is the intelligent pumping pipe, 9 is the control system, 10 is the water level sensor, and 11 is the flow rate sensor. DETAILED DESCRIPTION

[0036] In combination with the drawings Figures 1-2 and examples, the specific embodiments of the double-pipe wall intelligent well structure near a fault and its construction method provided by the present application are further described.

[0037] A double-pipe wall intelligent well structure near a fault, comprising a well body and an intelligent pumping system. Preferably, the well body is a double-pipe structure, comprising an inner pipe 5 and an outer pipe 6; a gap exists between the inner pipe 5 and the outer pipe 6, and a plurality of inflatable capsules 7 are arranged in the gap at intervals, which support the whole wellbore and prevent the wellbore from deforming. The length of the inflatable capsule 7 is 1.5 m, and the pressure difference between the inside and outside of the inflatable capsule 7 is 1.0 Mpa under the premise of meeting the stress intensity of the inner pipe 5 and the outer pipe 6.

[0038] Preferably, the intelligent pumping system comprises an intelligent pumping pipe 8, a control system 9, a water level sensor 10 and a flow rate sensor 11; the control system 8 is arranged on the ground near the wellhead; the intelligent pumping pipe 8 extends into the inside of the well body and is close to the position of the well bottom 4; the water level sensor 10 and the flow rate sensor 11 are both fixed to the inside of the pipe wall of the inner pipe 5 and are close to the lower part of the well. The intelligent pumping pipe 8, the water level sensor 10 and the flow rate sensor 11 are all electrically connected with the control system 9.

[0039] Further preferably, the outer pipe 6 is sequentially provided with a water-resisting stable section 6-1, a filter section 6-2 and a filter pipe section 6-3 from top to bottom. The water-resisting stable section 6-1 is made of clay balls, the clay ball has a clay particle content of not less than 65% of the total components, a sand content of less than 18% of the total components, a water content of less than 13% of the total components, and a dry density of greater than 2.0 g / cm 3 ; the filter section 6-2 is made of filter material with a particle size of 0.5-2.5 cm, and 25%-35% of coarse sand is added and stirred uniformly; the filter pipe section 6-3 is made of a bridge-type filter pipe with a thickness of 8 mm, and the specification of the filter mesh of the filter pipe can be selected according to the actual formation conditions.

[0040] Further preferably, a plurality of water inlets are formed in the pipe wall of the inner pipe 5 at the position of the filter pipe section 6-3 of the outer pipe 6. The water-resisting stable section 6-1 is a water-impermeable structure, the groundwater enters the outer pipe 6 after being filtered by the filter section 6-2, then reaches the lowermost filter pipe section 6-3, and then enters the well by the plurality of small water inlets in the pipe wall of the inner pipe 5 by using the pressure difference between the inside and outside of the pipe wall.

[0041] The specific construction steps of the double-pipe wall intelligent well structure are as follows:

[0042] S1. Before the construction near the fault 2, the overall geological conditions around the fault 2 are explored in detail, mainly including rock type, rock structure and underground water flow characteristics; according to the above exploration results, the reduction requirement of underground water level in the construction scheme is evaluated; S2. According to the geological exploration results and the control requirement of underground water level obtained in step S1, the specific excavation position of the pumping well body and the configuration parameters and models of each component in the intelligent pumping system are determined, and the design scheme of the double-pipe-wall intelligent pumping well is obtained; S3. According to the design scheme in S2, the well shaft is excavated and the outer pipe 6 is installed, and the outer pipe 6 is sequentially divided into the filter pipe section 6-3, the filter material section 6-2 and the water-resisting stable section 6-1 from bottom to top; S4. The inner pipe 5 is installed in the outer pipe 6, and a plurality of inflatable capsules 7 are arranged in the gap between the inner pipe 5 and the outer pipe 6, which can prevent the deformation of the well shaft by the supporting performance and sealing effect of the inflatable capsules 7; finally, the well bottom 4 of the pumping well is sealed by using PVC material, and the installation work of the pumping well body is completed; S5. The control system 9 of the intelligent pumping system is installed on the ground 1 near the well mouth, the water level sensor 10 and the flow rate sensor 11 are installed on the inner side of the pipe wall of the inner pipe 5, which can monitor the underground water level and flow rate in real time, and the control system can automatically adjust the pumping amount according to the monitoring results of the water level sensor 10 and the flow rate sensor 11; S6. During the whole construction process, the underground water level, flow rate and dewatering effect are continuously monitored, and the parameters of the intelligent pumping system are adjusted in time, and in actual engineering application, it is very important to adjust the pumping parameters according to the underground water level and flow rate to achieve the best dewatering effect.

[0043] In practical application, when the construction site is located in sandstone stratum, the underground water flow rate is fast, and the pumping speed is appropriately reduced to prevent the blockage of particles in the well shaft and ensure the stability of water flow; when the construction site is located in clay stratum, the underground water flow rate is slow, and the pumping speed and water level need to be paid special attention during the pumping process, and the intermittent pumping method can be used to allow the underground water to recover during the pumping interval.

[0044] Finally, after the completion of the project, the dewatering effect and the stability of the well shaft of the intelligent pumping well are evaluated: a. continuously monitor the change of underground water level to evaluate the dewatering effect; b. monitor the deformation of the inner and outer diameters of the well shaft to evaluate the stability of the well shaft; c. detect the water quality of the underground water to ensure that the water quality meets the requirements. The intelligent pumping well structure provided by the present application can realize effective dewatering control of underground water level in rock and soil engineering near the fault, and the overall stability of the well shaft is good.

[0045] It is also worth mentioning that, considering the discontinuity of underground water distribution caused by the fault, the present application takes the normal fault as an example (such as Figure 2As shown in the figure), the underground water level of the lower wall is higher than that of the upper wall, at this time, the left and right sides of the outer tube 6 adopt water-resisting stable sections 6-1 with different heights according to the shape of the fault 2 and the underground water level, and the length of the water-resisting stable section 6-1 near the lower wall side is greater than that of the water-resisting stable section 6-1 near the upper wall side, so as to meet the water source filtering of the water well at the fault to different underground water levels.

[0046] In the present application, the terms such as "upper", "lower", "bottom", "top" and the like indicate the orientation or positional relationship shown in the drawings, which is only a relationship word determined for the convenience of describing the structural relationship of the components or elements of the present application, and is not intended to specify any component or element in the present application, and cannot be understood as a limitation on the present application. The terms such as "connected", "connected" and the like should be understood broadly, which means that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For relevant researchers or technicians in the field, the specific meaning of the above terms in the present application can be determined according to the specific circumstances, and cannot be understood as a limitation on the present application.

[0047] Of course, the above description is not a limitation on the present application, and the present application is not limited to the above examples. Changes, modifications, additions or replacements made by the skilled in the art within the essential scope of the present application should also be within the protection scope of the present application.

Claims

1. A double-tube wall intelligent pumping well structure near a fault, comprising a pumping well body and an intelligent pumping system, characterized in that, The well body is a double-pipe structure; the intelligent pumping system comprises an intelligent pumping pipe, a water level sensor, a flow rate sensor and a control system; the control system is arranged on the ground; the intelligent pumping pipe extends into the well body; The double-pipe structure comprises an inner pipe and an outer pipe; a gap exists between the inner pipe and the outer pipe, and a plurality of inflatable capsules are arranged in the gap at intervals; The outer pipe is divided into a water-stable section, a filter section and a filter pipe section from top to bottom; The water-stable section has different heights on the left and right sides of the outer pipe according to the shape of the fault and the height of the underground water level, so as to meet the water source filtering requirements of the well at the fault for different underground water levels.

2. The near fault double wall intelligent water well structure according to claim 1, wherein, The length of the inflatable capsule is 1.5 m, and the pressure difference between the inside and outside of the inflatable capsule is 1.0 Mpa.

3. The near fault double wall intelligent water well structure according to claim 1, wherein, The water-proof stable section is made of clay ball material; the clay ball has a clay particle content of not less than 65% of total components, a sand content of less than 18% of total components, a water content of less than 13% of total components, and a dry density of greater than 2.0 g / cm 3 ; The filter section uses filter material with a particle size of 0.5-2.5 cm, and 25-35% of coarse sand is added and stirred uniformly to form the filter section; The filter pipe section uses a bridge-type filter pipe with a thickness of 8 mm.

4. The near fault double wall intelligent water well structure according to claim 1, wherein, The water level sensor and the flow rate sensor are fixed to the inner side of the inner pipe wall.

5. The near fault double wall intelligent water well structure according to claim 1, wherein, The intelligent pumping pipe, the water level sensor and the flow rate sensor are electrically connected to the control system.

6. The near fault double wall intelligent water well structure according to claim 1, wherein, A plurality of water inlets are also formed in the inner pipe wall of the filter pipe section of the outer pipe.

7. The near fault double wall intelligent water well structure according to claim 1, wherein, The bottom of the well body is sealed by a PVC material.

8. A method of constructing a near-fault double-wall smart well structure, characterized by, The double-pipe wall intelligent well structure near the fault comprises the following steps: S1. Geological exploration and evaluation Before the construction, the geological conditions around the fault are explored in detail, including rock type, rock structure and underground water flow characteristics; according to the exploration results of the geological conditions, the reduction requirement of the underground water level in the construction scheme is evaluated; S2. Design scheme and determination of well position According to the geological exploration results in S1 and the control requirement of the underground water level, the position of the well body and the configuration parameters of each component in the intelligent pumping system are determined, and the design scheme of the well is obtained; S3. Excavation of wellbore and installation of outer pipe According to the design scheme in S2, the wellbore is excavated and the outer pipe is installed, and the outer pipe is sequentially provided with a filter pipe section, a filter section and a water-stable section from bottom to top; S4. Installation and fixation of inner pipe and sealing of well bottom The inner pipe is installed in the outer pipe, and a plurality of inflatable capsules are arranged in the gap between the inner pipe and the outer pipe at intervals, so as to prevent the deformation of the wellbore by the supporting performance and sealing effect of the inflatable capsules; finally, the well bottom is sealed by a PVC material; S5. Installation of intelligent pumping system The control system of the intelligent pumping system is installed on the ground, and the water level sensor and the flow rate sensor are installed on the inner side of the inner pipe wall, so as to monitor the underground water level and water flow rate in real time, and the control system automatically adjusts the pumping amount according to the monitoring results; S6. Construction monitoring and adjustment During the whole construction process, the underground water level, water flow rate and dewatering effect are continuously monitored, and the parameters of the intelligent pumping system are adjusted in a timely manner according to the monitoring results.

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