Method and system for detecting defects of vertical impervious curtain
阅读说明：本技术 一种用以检测垂直防渗帷幕缺陷的方法和系统 (Method and system for detecting defects of vertical impervious curtain ) 是由 *** 杨亮 杨铸 徐亚 刘玉强 张尚锁 万越 朱海 万娟 朱中静 于 2019-09-16 设计创作，主要内容包括：本发明提供一种用以检测垂直防渗帷幕缺陷的方法和系统,所述方法包括：步骤S1：围绕垂直防渗帷幕布置多组试验井,其中每一组所述试验井包括位于垂直防渗帷幕一侧的抽水井和位于所述垂直防渗帷幕另一侧的观测井；步骤S2：对每一组所述试验井的所述观测井的进行背景水位测定试验,以获得所述观测井的背景水位随时间变化的数据；步骤S3：对每一组所述试验井的所述抽水井进行抽水试验,以获得所述观测井的动态水位随时间变化的数据；步骤S4：对每一组所述试验井的所述背景水位随时间变化的数据和所述动态水位随时间变化的数据进行对比判断所述垂直防渗帷幕的缺陷情况。根据本发明能够准确判定垂直防渗墙的缺陷情况。(The invention provides a method and a system for detecting defects of a vertical impervious curtain, wherein the method comprises the following steps: step S1: arranging a plurality of groups of test wells around the vertical impervious curtain, wherein each group of test wells comprises a pumping well positioned on one side of the vertical impervious curtain and an observation well positioned on the other side of the vertical impervious curtain; step S2: performing a background water level determination test on the observation wells of each group of the test wells to obtain data of the change of the background water level of the observation wells along with time; step S3: carrying out pumping tests on the pumping wells of each group of test wells to obtain data of the dynamic water level of the observation well changing along with time; step S4: and comparing the data of the background water level changing along with the time of each group of test wells with the data of the dynamic water level changing along with the time to judge the defect condition of the vertical impervious curtain. According to the invention, the defect condition of the vertical impervious wall can be accurately judged.)
1. A method for detecting defects in a vertical impervious curtain, comprising:
step S1: arranging a plurality of groups of test wells around the vertical impervious curtain, wherein each group of test wells comprises a pumping well positioned on one side of the vertical impervious curtain and an observation well positioned on the other side of the vertical impervious curtain;
step S2: performing a background water level determination test on the observation wells of each group of the test wells to obtain data of the change of the background water level of the observation wells along with time;
step S3: carrying out pumping tests on the pumping wells of each group of test wells to obtain data of the dynamic water level of the observation well changing along with time;
step S4: comparing the data of the background water level changing with time and the data of the dynamic water level changing with time of each group of the test wells to judge the defect condition of the vertical impervious curtain, wherein,
when the dynamic water level of the observation well in the test well is unchanged or the change of the dynamic water level of the observation well is smaller than the change of the background water level of the observation well, the dynamic water level of the observation well is judged to be normal, and the integrity of the vertical impervious curtain is good; otherwise, judging that the dynamic water level of the observation well is abnormal, and the vertical impervious curtain has defects.
2. The method of claim 1, wherein the step S1 includes:
step S11: determining the distance between the well position of the test well and the impervious curtain;
step S12: determining the distance between the well positions of two adjacent groups of test wells and the detection range of each group of test wells;
step S13: constructing to dig a well according to the distance between the test well positions and the impervious curtains determined in the step S11, the distance between two adjacent groups of the test well positions determined in the step S12 and the detection range of each group of the test wells.
3. The method of claim 1, wherein the test well is pumped and flushed during the step S1 of deploying the test well so that the water pumped from the test well is free of silt.
4. The method as claimed in claim 2, wherein the distance between the test well position and the impervious curtain is 1.5 times to 2.5 times the diameter of the pumping well hole in the step S11.
5. The method of claim 2, wherein in step S12, the spacing d between adjacent test wells satisfies R ≦ d ≦ 2R, wherein R is based on empirical formula
6. The method as recited in claim 1, in said step S2, further comprising plotting the background water level of said observation well over time based on the data of the background water level of said observation well over time; and
in step S3, the method further includes drawing a time-varying curve of the dynamic water level of the observation well according to the time-varying data of the dynamic water level of the observation well.
7. The method of claim 4, wherein the step of comparing the time-dependent background water level data and the time-dependent dynamic water level data for each set of the test wells comprises comparing a time-dependent background water level profile of the observation wells to a time-dependent dynamic water level profile of the observation wells.
8. The method of claim 5, further comprising, when it is determined that the vertical impervious curtain has a defect, further determining a range where the defect exists.
9. The method of claim 8, wherein the step of further determining the range in which the defect location exists comprises:
and when the distance d between two adjacent groups of test well positions is equal to 2R, the integrity of the vertical impervious wall in the detection range of each group of test wells is directly judged according to a relation curve of the dynamic water level changing along with time, which is measured by a pumping test of the vertical impervious wall.
10. The method of claim 8, wherein the step of further determining the range in which the defect location exists comprises:
when the distance d between two adjacent groups of the test well positions satisfies that R is more than or equal to d and less than 2R,
if the dynamic water level of the observation well of one group of the test wells is abnormal, and the dynamic water level of the observation well of the other group of the test wells is normal, determining that the defect is located in the range that the center point of the test well with the abnormal dynamic water level of the observation well is close to one side of the test well with the abnormal dynamic water level of the observation well and the radius of one side of the test well is R;
and if the dynamic water levels of the observation wells of each group of the test wells are abnormal, judging that:
1) 1 defect exists between the central points of the two adjacent groups of test wells, and the defect is located in a range with the center point between the central points of the two groups of test wells as the circle center and the radius of d/2; or
2) There are more than 2 defects, and 2 defects belong to any one of the following three cases:
the two adjacent groups of the test wells comprise a first group of the test wells and a second group of the test wells which are adjacent,
a: the radius of the center point of the first group of test wells close to one side of the second group of test wells is within a range d;
b: the second group of the test well center points are close to the area within the range of the radius d of one side of the first group of the test wells;
c: and taking the midpoint between the central points of the two groups of test wells as the circle center and the radius of the midpoint as the range of d/2.
11. A system for detecting defects in a vertical impervious curtain, comprising:
a plurality of groups of test wells arranged around the vertical impervious curtain, wherein each group of test wells comprises a pumping well positioned in the inner area of the vertical impervious curtain and an observation well positioned in the outer area of the vertical impervious curtain;
the water pumping measuring device is used for performing a water pumping test on the water pumping well;
the water level detection device is used for detecting the water level of the observation well before the water pumping test is carried out on the water pumping well by the water pumping measuring device or during the water pumping test so as to respectively obtain data of the change of the background water level of the observation well with time and data of the change of the dynamic water level of the observation well with time.
12. The system of claim 9, wherein the test well comprises an underground tubular and a subterranean tubular, the subterranean tubular comprising a settling tube, a strainer, and a casing tube arranged in that order from bottom to top;
the above-ground tubular comprises a wellhead casing comprising a protective casing, a plastic cover plate and a protective cover plate.
Technical Field
The invention relates to the field of garbage disposal, in particular to a method and a system for detecting defects of a vertical impervious curtain.
Background
Along with the development of national economy, the living standard of people is increasingly improved, the population of cities is continuously increased, the number of municipal solid wastes is increased, and the wastes must be treated in order to prevent the wastes from polluting the environment.
A safety landfill is a disposal facility for disposing or storing hazardous waste garbage in soil, the purpose of which is to bury or change the characteristics of hazardous waste, and is suitable for landfill disposal of hazardous waste which cannot recycle its useful components and cannot recycle its energy. The general aim of a safety landfill is to isolate the hazardous waste from the environment as much as possible, so that a containment curtain must be placed around the safety landfill. The anti-seepage performance of the anti-seepage curtain influences the safety of the surrounding environment. In the prior art, a geophysical prospecting method is often used to detect the structural integrity of the vertical impervious curtains.
Due to the poor adaptability of the geophysical prospecting technology to complex engineering conditions and detection environments and the limited detection precision of the equipment, the defect condition in the vertical impervious curtain cannot be accurately judged.
Therefore, there is a need for a system and method for detecting defects in a vertical impervious curtain, which solves the problems of the prior art.
Disclosure of Invention
In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
The invention provides a method for detecting defects of a vertical impervious curtain, which comprises the following steps:
step S1: arranging a plurality of groups of test wells around the vertical impervious curtain, wherein each group of test wells comprises a pumping well positioned on one side of the vertical impervious curtain and an observation well positioned on the other side of the vertical impervious curtain;
step S2: performing a background water level determination test on the observation wells of each group of the test wells to obtain data of the change of the background water level of the observation wells along with time;
step S3: carrying out pumping tests on the pumping wells of each group of test wells to obtain data of the dynamic water level of the observation well changing along with time;
step S4: comparing the data of the background water level changing with time and the data of the dynamic water level changing with time of each group of the test wells to judge the defect condition of the vertical impervious curtain, wherein,
when the dynamic water level of the observation well in the test well is unchanged or the change of the dynamic water level of the observation well is smaller than the change of the background water level of the observation well, the dynamic water level of the observation well is judged to be normal, and the integrity of the vertical impervious curtain is good; otherwise, judging that the dynamic water level of the observation well is abnormal, and the vertical impervious curtain has defects.
Exemplarily, the step S1 includes:
step S11: determining the distance between the well position of the test well and the impervious curtain;
step S12: determining the distance between the well positions of two adjacent groups of test wells and the detection range of each group of test wells;
step S13: constructing to dig a well according to the distance between the test well positions and the impervious curtains determined in the step S11, the distance between two adjacent groups of the test well positions determined in the step S12 and the detection range of each group of the test wells.
Illustratively, the test well is pumped and washed during the step S1 of arranging the test well so that the water pumped from the test well is free of silt.
Illustratively, the distance between the well testing position and the impervious curtain in the step S11 is 1.5-2.5 times of the aperture of the well testing.
Illustratively, in the step S12, the distance d between adjacent test wells satisfies R ≦ d ≦ 2R, where R is based on an empirical formula
Exemplarily, in the step S2, the method further includes plotting a time-varying curve of the background water level of the observation well according to the time-varying data of the background water level of the observation well; and
in step S3, the method further includes drawing a time-varying curve of the dynamic water level of the observation well according to the time-varying data of the dynamic water level of the observation well.
Illustratively, the step of comparing the time-dependent background water level data and the time-dependent dynamic water level data for each set of the test wells comprises comparing a time-dependent background water level profile of the observation wells with a time-dependent dynamic water level profile of the observation wells.
Illustratively, when the vertical impervious curtain is judged to have defects, the range of the positions of the defects is further judged.
Illustratively, the step of further judging the range in which the defect position exists includes:
and when the distance d between two adjacent groups of test well positions is equal to 2R, the integrity of the vertical impervious wall in the detection range of each group of test wells is directly judged according to a relation curve of the dynamic water level changing along with time, which is measured by a pumping test of the vertical impervious wall.
Illustratively, the step of further judging the range in which the defect position exists includes:
when the distance d between two adjacent groups of the test well positions satisfies that R is more than or equal to d and less than 2R,
if the dynamic water level of the observation well of one group of the test wells is abnormal, and the dynamic water level of the observation well of the other group of the test wells is normal, determining that the defect is located in the range that the center point of the test well with the abnormal dynamic water level of the observation well is close to one side of the test well with the abnormal dynamic water level of the observation well and the radius of one side of the test well is R;
and if the dynamic water levels of the observation wells of each group of the test wells are abnormal, judging that:
1) 1 defect exists between the central points of the two adjacent groups of test wells, and the defect is located in a range with the center point between the central points of the two groups of test wells as the circle center and the radius of d/2; or
2) There are more than 2 defects, and 2 defects belong to any one of the following three cases:
the two adjacent groups of the test wells comprise a first group of the test wells and a second group of the test wells which are adjacent,
a: the radius of the center point of the first group of test wells close to one side of the second group of test wells is within a range d;
b: the second group of the test well center points are close to the area within the range of the radius d of one side of the first group of the test wells;
c: and taking the midpoint between the central points of the two groups of test wells as the circle center and the radius of the midpoint as the range of d/2.
The present invention also provides a system for detecting defects of a vertical impervious curtain, comprising:
a plurality of groups of test wells arranged around the vertical impervious curtain, wherein each group of test wells comprises a pumping well positioned in the inner area of the vertical impervious curtain and an observation well positioned in the outer area of the vertical impervious curtain;
the water pumping measuring device is used for performing a water pumping test on the water pumping well;
the water level detection device is used for detecting the water level of the observation well before the water pumping test is carried out on the water pumping well by the water pumping measuring device or during the water pumping test so as to respectively obtain data of the change of the background water level of the observation well with time and data of the change of the dynamic water level of the observation well with time.
Illustratively, the test well comprises an underground pipe and a subterranean pipe, wherein the subterranean pipe comprises a sedimentation pipe, a water filter pipe and a well wall pipe which are arranged in sequence from bottom to top;
the above-ground tubular comprises a wellhead casing comprising a protective casing, a plastic cover plate and a protective cover plate.
According to the method and the system for detecting the defects of the vertical impervious curtain, disclosed by the invention, the periodic change rule of underground water and the dynamic change characteristics of the underground water level are obtained by observing the background water level and the dynamic water level of the test well, the hydraulic connection strength of the underground water on two sides of the vertical impervious curtain is determined, and therefore whether the vertical impervious wall really has structural defects can be effectively detected and judged.
Drawings
The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
In the drawings:
FIG. 1 is a flowchart of a method for detecting defects in a vertical impervious curtain according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a test well in a method for detecting defects in a vertical impervious curtain according to an embodiment of the present invention;
FIG. 3 is a schematic view of a test well arranged in a detection area of a vertical impervious curtain in a method for detecting defects of the vertical impervious curtain according to an embodiment of the present invention;
4A-4E are graphs of pumping well water level depression versus time for a pumping test on a pumping well having 5 sets of test wells according to one example of the present invention; and
figures 5A-5E are graphs of water level drop in observation wells as a function of time for a pumping trial of a pumping well having 5 test wells according to one example of the invention.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.
In order to provide a thorough understanding of the present invention, a detailed description will be provided in the following description to illustrate a method and system for detecting defects of a vertical impervious curtain of the present invention. It will be apparent that the practice of the invention is not limited to the specific details known to those skilled in the art of waste treatment. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.
It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular is intended to include the plural unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Exemplary embodiments according to the present invention will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art. In the drawings, the thicknesses of layers and regions are exaggerated for clarity, and the same elements are denoted by the same reference numerals, and thus the description thereof will be omitted.
A safety landfill is a disposal facility for disposing or storing hazardous waste garbage in soil, the purpose of which is to bury or change the characteristics of hazardous waste, and is suitable for landfill disposal of hazardous waste which cannot recycle its useful components and cannot recycle its energy. The general aim of a safety landfill is to isolate the hazardous waste from the environment as much as possible, so that a containment curtain must be placed around the safety landfill. The anti-seepage performance of the anti-seepage curtain influences the safety of the surrounding environment. In the prior art, a geophysical prospecting method is often used to detect the structural integrity of the vertical impervious curtains.
Due to the poor adaptability of the geophysical prospecting technology to complex engineering conditions and detection environments and the limited detection precision of the equipment, the defect condition in the vertical impervious curtain cannot be accurately judged.