CN103147467A - Leak detection device for underground diaphragm wall and construction method of leak detection device - Google Patents
Leak detection device for underground diaphragm wall and construction method of leak detection device Download PDFInfo
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- CN103147467A CN103147467A CN2013100804304A CN201310080430A CN103147467A CN 103147467 A CN103147467 A CN 103147467A CN 2013100804304 A CN2013100804304 A CN 2013100804304A CN 201310080430 A CN201310080430 A CN 201310080430A CN 103147467 A CN103147467 A CN 103147467A
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Abstract
The invention provides a leak detection device for an underground diaphragm wall, and a construction method of the leak detection device. The detection device comprises a composite water level monitoring well at a seam of the diaphragm wall to be detected; a wellhole of the monitoring well is internally provided with a plurality of well tubes; the bottom ends of the well tubes penetrate to-be-detected confined water layers in different depths respectively; the to-be-detected confined water layers are covered by filter materials; and the filter materials of the to-be-detected confined water layers are separated by clay balls. The construction method comprises the steps of constructing at least one wellhole, placing the first well tube in the wellhole, allowing the first well tube to penetrate the undermost confined water layer, backfilling the filter material and the clay balls into the wellhole, placing the second well tube in the wellhole, allowing the second well tube to penetrate the second confined water layer, backfilling the filter material and the clay balls into the wellhole, placing the Nth well tube in the wellhole according to the number of the required detection layers in sequence, allowing the Nth well tube to penetrate the uppermost confined water layer, backfilling the filter material and the clay balls, placing the (N+1)th well tube in the wellhole finally for monitoring a shallow water level, and backfilling the filter material to the ground level. Water level situations of the confined water layers can be reflected really.
Description
Technical field
The present invention relates to a kind of checkout gear and job practices thereof of diaphragm wall seepage, especially, relate to a kind of device and job practices thereof for detection of soft clay area deep footing groove enclosing structure diaphragm wall seepage situation.
Background technology
In deep footing groove enclosing structure construction and later stage foundation ditch, construction is subjected to the impact of artesian water larger, and the seepage situation easily occurs, and the dangerous situations such as piping, space enclosing structure unstability can occur when serious.Verify in advance dangerous situation, determine the seepage position, hidden danger is made administered and carry out the foundation ditch strengthening measure in advance, the safe construction of foundation ditch is had very important effect.In the so many underground construction of typical rich water soft clay area construction, the safe construction of foundation ditch is faced with formidable challenges.Diaphragm wall had obtained being widely used at underground space construction field as the good space enclosing structure of a kind of combination property in recent years.But the existence of the construction technology of diaphragm wall, joint form, the factor such as be subjected to that ground environment affects makes body of wall in digging process, more or less exists hidden leakage defect, and the excavation of foundation pit security risk exists constantly.Because body of wall is hidden under soil layer before excavation, artesian water and water barrier are having again discontinuous interlock, in the construction of diaphragm wall process and in digging process, artesian water can not represent to construction technical staff intuitively on the impact of body of wall, must take certain measure indirectly to observe the body of wall situation, distinguish whether risk of leakage is arranged, whether excavation of foundation pit is in safe controllable state.Therefore underground diaphragm wall seepage situation is necessary to design a kind of new checkout gear.
Summary of the invention
For overcoming the existing defective of prior art, the present invention proposes a kind of diaphragm wall leak detection apparatus and method thereof, judge by the observation to water level in the outside compound water level monitor well of laying of foundation ditch whether the correspondence position diaphragm wall seepage occurs, thereby take corresponding remedial measure.
Diaphragm wall leak detection apparatus of the present invention, described checkout gear comprises the compound water level monitor well that is opened in the diaphragm wall to be measured outside, described compound water level monitor well is positioned at the seam crossing of diaphragm wall, be provided with the complex root well casing in the wellhole of described compound water level monitor well, the bottom of described each well casing is deep into respectively the artesian aquifer to be measured of different depth, described each artesian aquifer to be measured covers by filtrate, and separates by clay ball between the filtrate of described each artesian aquifer to be measured.
Described compound water level monitor well is apart from diaphragm wall seam 1m to 3m.
The zone that the bottom of described each well casing is positioned at the artesian aquifer to be measured at its place offers through hole, and described through hole is wound with filter screen outward.
The job practices of diaphragm wall leak detection apparatus of the present invention comprises the following steps:
In at least one wellhole of the outside of diaphragm wall seam crossing to be detected construction, put into the first well casing in wellhole, make it go deep into the orlop artesian aquifer, cover this artesian aquifer toward interior backfill the first filtrate of wellhole, and then fill out the first clay ball;
Then put into the second well casing in wellhole, make its second layer artesian aquifer that gos deep into orlop artesian aquifer top, cover this artesian aquifer toward interior backfill the second filtrate of wellhole, and then fill out the second clay ball;
With this sequence construction, put into the N well casing according to the number of plies of required detection artesian aquifer in wellhole, go deep into the superiors' artesian aquifer, backfill N filtrate, cover this artesian aquifer in wellhole, and then fill out the N clay ball;
Put at last N+1 root well casing in wellhole, in order to monitor the shallow water water level, backfill N+1 filtrate is to ground level.
The bottom of described well casing is positioned at shoaling layer to be measured or the artesian aquifer zone at its place and offers through hole, and is wound with filter screen outside through hole.
The present invention makes its beneficial effect that has be owing to using above technical scheme:
In shoaling layer, artesian aquifer, water passes through the certain height of monitoring well casing rising of this layer under the effect of pressure, by measuring every SEA LEVEL VARIATION in the well casing that gos deep into different shoaling layers, artesian aquifer, obtain the data of underground different shoaling layer, artesian aquifer, can judge the proterties of shallow water, artesian water, thereby analyze the situation whether the deep footing groove enclosing structure diaphragm wall seepage occurs.The present invention is also by the way at the compound water level monitor well of diaphragm wall seam outside certain distance construction, the outer underground SEA LEVEL VARIATION in combination monitoring hole of one well multitube, reduced the usage space of leak detection process, improve monitoring of leakage efficient, and can continuous monitoring the wall quality situation of different depth at same position, accuracy of detection is high, and detection method is simply easy to implement.
Description of drawings
Fig. 1 is water level combined monitoring well construction flow chart 1 of the present invention;
Fig. 2 is water level combined monitoring well construction flow chart 2 of the present invention;
Fig. 3 is water level combined monitoring well construction flow chart 3 of the present invention;
Fig. 4 is water level combined monitoring well construction flow chart 4 of the present invention;
Fig. 5 is water level combined monitoring well construction flow chart 5 of the present invention;
Fig. 6 is water level combined monitoring well construction flow chart 6 of the present invention;
Fig. 7 is water level combined monitoring well construction flow chart 7 of the present invention;
Fig. 8 is the well casing bottom opening schematic diagram of water level combined monitoring well of the present invention;
Fig. 9 is the layout schematic diagram of water level combined monitoring well of the present invention and diaphragm wall.
The specific embodiment
For the benefit of to the understanding of structure of the present invention, describe below in conjunction with drawings and Examples.
In conjunction with shown in Figure 7, diaphragm wall leak detection apparatus of the present invention, take monitoring one deck shoaling layer, two-layer artesian aquifer as example, at first offer at least one compound water level monitor well in the outside of diaphragm wall seam crossing to be measured, in conjunction with shown in Figure 9, monitor well and diaphragm wall 9 seams 10 are at a distance of 1m to 3m.being provided with three calibers in the wellhole 1 of monitor well is 110mm, the pvc pipe of wall thickness 2.5mm is as well casing 2, 2 of well casings adopt pipe collar to connect, the bottom of each well casing 2 offers plural through hole 7, as shown in Figure 8, through hole 7 is offered scope and is these well casing 2 place shoaling layers, the thickness of artesian aquifer, and the outer filter screen that is wound with of through hole 7, in order to the impurity such as sandstone particle in filtered water, in order to avoid stop up well casing 2, each well casing 2 is deep into respectively the bottom of different water layers to be measured simultaneously, each water layer to be measured covers by filtrate 3, but the impurity such as sandstone particle in filtrate 3 filtered water, make simultaneously part and the soil layer of the interior filling filtrate 3 of wellhole 1 keep certain stability, and 3 of the filtrates of each water layer to be measured separate by clay ball 4.
To shown in Figure 7, the job practices of diaphragm wall leak detection apparatus of the present invention comprises in conjunction with Fig. 1:
at least one wellhole 1 of outside left construction at diaphragm wall seam crossing to be detected, the diameter of wellhole 1 is 600mm, wellhole 1 is deeply to orlop artesian aquifer to be detected 5 positions, put into the first well casing 21 in the good wellhole 1 of construction, make it go deep into bottom artesian aquifer 5, toward interior backfill the first filtrate 31 of wellhole 1, the first filtrate 31 covers orlop artesian aquifer 5, then backfill the first clay ball 41 on the first filtrate 31, and offer through hole 7 in the first well casing 21 bottoms according to the thickness of orlop artesian aquifer 5 on tube wall, as shown in Figure 8, the aperture of through hole 7 is 5mm, spacing 3cm * 3cm, the scope of offering of through hole 7 is orlop artesian aquifer 5 thickness, and at first well casing 21 perforate scope outer cladding 4mm * 4mm plastic filter screens, filter screen is around 21 liang of circles of the first well casing, in order to isolate large-sized particle, in order to avoid through hole 7 is stopped up.
Put into the second well casing 22 in wellhole 1, the second well casing 22 and the first well casing 21 spacings are the 200mm left and right, make it go deep into middle level artesian aquifer 6, toward interior backfill the second filtrate 32 of wellhole 1, the second filtrate 32 covers middle level artesian aquifer 6, then fill out the second clay ball 42, equally offer through hole 7 according to the thickness of middle level artesian aquifer 6 in the second well casing 22 bottoms, and at perforate scope outer cladding two circle plastic filter screens.
Then at interior placement the 3rd well casing 23 of wellhole 1, make it go deep into shoaling layer 8, about the 3rd well casing 23 branches and the first well casing 21, the second well casing 22 spacing 200mm, three well casings 2 are overlooked downwards formed one " product " font layout (as Fig. 9), and around the 3rd well casing 23 backfill the 3rd filtrate 33 to ground level, the 3rd filtrate 33 is covered shoaling layer 8, and enter the shoaling layer thickness range according to the thickness of shoaling layer 8 at the 3rd well casing 23 in the same way and offer through hole 7, and at perforate scope outer cladding two circle plastic filter screens.
The top of three well casings 2 all exceeds the height of ground 1m, is convenient to measurement and the sign of water level, has also realized effect attractive in appearance, and teeming stage carries out well casing 2 protections.
Complete compound water level monitor well construction, in shoaling layer, artesian aquifer, water passes through the well casing 2 certain height of rising of this layer under the effect of pressure, by measuring three interior SEA LEVEL VARIATION of well casing 2 that rise up into different water layers, obtain the data of underground different water layers, can judge the proterties of shoaling layer and artesian aquifer, thereby analyze the situation whether the deep footing groove enclosing structure diaphragm wall seepage occurs.The present invention is also by the way at the compound water level monitor well of diaphragm wall seam outside certain distance construction, the outer underground SEA LEVEL VARIATION in combination monitoring hole of one well multitube, reduced the usage space of leak detection process, improve monitoring of leakage efficient, and can continuous monitoring the wall quality situation of different depth at same position, accuracy of detection is high, and detection method is simply easy to implement.
Claims (5)
1. diaphragm wall leak detection apparatus, it is characterized in that: described checkout gear comprises the compound water level monitor well that is opened in the diaphragm wall to be measured outside, described compound water level monitor well is positioned at the seam crossing of diaphragm wall, be provided with the complex root well casing in the wellhole of described compound water level monitor well, the bottom of described each well casing is deep into respectively the artesian aquifer to be measured of different depth, described each artesian aquifer to be measured covers by filtrate, and separates by clay ball between the filtrate of described each artesian aquifer to be measured.
2. checkout gear as claimed in claim 1, it is characterized in that: described compound water level monitor well is apart from diaphragm wall seam 1m to 3m.
3. checkout gear as claimed in claim 1, it is characterized in that: the zone that the bottom of described each well casing is positioned at the artesian aquifer to be measured at its place offers through hole, and described through hole is wound with filter screen outward.
4. the job practices of a diaphragm wall leak detection apparatus is characterized in that comprising the following steps:
In at least one wellhole of the outside of diaphragm wall seam crossing to be detected construction, put into the first well casing in wellhole, make it go deep into the orlop artesian aquifer, cover this artesian aquifer toward interior backfill the first filtrate of wellhole, and then fill out the first clay ball;
Then put into the second well casing in wellhole, make its second layer artesian aquifer that gos deep into orlop artesian aquifer top, cover this artesian aquifer toward interior backfill the second filtrate of wellhole, and then fill out the second clay ball;
With this sequence construction, put into the N well casing according to the number of plies of required detection artesian aquifer in wellhole, go deep into the superiors' artesian aquifer, backfill N filtrate, cover this artesian aquifer in wellhole, and then fill out the N clay ball;
Put at last N+1 root well casing in wellhole, in order to monitor the shallow water water level, backfill N+1 filtrate is to ground level.
5. job practices as claimed in claim 4 is characterized in that: the bottom of described well casing is positioned at shoaling layer to be measured or the artesian aquifer zone at its place and offers through hole, and is wound with filter screen outside through hole.
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| CN2013100804304A CN103147467A (en) | 2013-03-13 | 2013-03-13 | Leak detection device for underground diaphragm wall and construction method of leak detection device |
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| CN2013100804304A CN103147467A (en) | 2013-03-13 | 2013-03-13 | Leak detection device for underground diaphragm wall and construction method of leak detection device |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103266638A (en) * | 2013-06-14 | 2013-08-28 | 江苏方建工程质量鉴定检测有限公司 | Detection method of leakage site position of underground concrete continuous wall |
| CN103471978A (en) * | 2013-10-08 | 2013-12-25 | 中国水电顾问集团西北勘测设计研究院 | Face plate dam leakage monitor structure on deep covering layer |
| CN103628510A (en) * | 2013-12-17 | 2014-03-12 | 上海岩土工程勘察设计研究院有限公司 | Underground diaphragm wall model for test of underground diaphragm wall defect detection method |
| CN104314091A (en) * | 2014-10-20 | 2015-01-28 | 中国建筑第八工程局有限公司 | Around-foundation pit water level observation well pumping system |
| CN106320397A (en) * | 2016-08-28 | 2017-01-11 | 神翼航空器科技（天津）有限公司 | Advanced prediction and renovation method for foundation pit seepage |
| CN106320393A (en) * | 2016-08-21 | 2017-01-11 | 浙江科技学院 | Leak detection method for underground diaphragm wall in soft soil area |
| CN107178076A (en) * | 2017-05-05 | 2017-09-19 | 张浩冉 | It is a kind of to be segmented controllable seepage well of pouring water |
| CN109060073A (en) * | 2018-10-17 | 2018-12-21 | 贵州省水利水电勘测设计研究院 | Single hole observes Karst Mountain bilayer level of ground water device and method |
| CN110541436A (en) * | 2019-08-20 | 2019-12-06 | 浙江大学 | Double-layer HDPE (high-density polyethylene) film vertical antifouling barrier structure containing leakage detection layer and method |
| CN111305180A (en) * | 2020-02-24 | 2020-06-19 | 姚燕明 | Foundation pit confined water early warning equipment system and monitoring method |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103471978A (en) * | 2013-10-08 | 2013-12-25 | 中国水电顾问集团西北勘测设计研究院 | Face plate dam leakage monitor structure on deep covering layer |
| CN103628510A (en) * | 2013-12-17 | 2014-03-12 | 上海岩土工程勘察设计研究院有限公司 | Underground diaphragm wall model for test of underground diaphragm wall defect detection method |
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| CN106320393B (en) * | 2016-08-21 | 2018-08-28 | 浙江科技学院 | A kind of soft clay area diaphram wall leakage detection method |
| CN106320393A (en) * | 2016-08-21 | 2017-01-11 | 浙江科技学院 | Leak detection method for underground diaphragm wall in soft soil area |
| CN106320397A (en) * | 2016-08-28 | 2017-01-11 | 神翼航空器科技（天津）有限公司 | Advanced prediction and renovation method for foundation pit seepage |
| CN106320397B (en) * | 2016-08-28 | 2018-05-29 | 神翼航空器科技（天津）有限公司 | The advanced prediction of Leakage of Foundation Pit and advanced regulation method |
| CN107178076A (en) * | 2017-05-05 | 2017-09-19 | 张浩冉 | It is a kind of to be segmented controllable seepage well of pouring water |
| CN109060073A (en) * | 2018-10-17 | 2018-12-21 | 贵州省水利水电勘测设计研究院 | Single hole observes Karst Mountain bilayer level of ground water device and method |
| CN110541436A (en) * | 2019-08-20 | 2019-12-06 | 浙江大学 | Double-layer HDPE (high-density polyethylene) film vertical antifouling barrier structure containing leakage detection layer and method |
| CN110541436B (en) * | 2019-08-20 | 2021-04-06 | 浙江大学 | Double-layer HDPE (high-density polyethylene) film vertical antifouling barrier structure containing leakage detection layer and method |
| CN111305180A (en) * | 2020-02-24 | 2020-06-19 | 姚燕明 | Foundation pit confined water early warning equipment system and monitoring method |
| CN111305180B (en) * | 2020-02-24 | 2024-05-17 | 宁波市轨道交通集团有限公司 | Early warning equipment system and monitoring method for foundation pit confined water |
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Application publication date: 20130612 |