CN110424430A - Deep basal pit powder land floor Deep Pumped Wells construction method and its application - Google Patents

Deep basal pit powder land floor Deep Pumped Wells construction method and its application Download PDF

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Publication number
CN110424430A
CN110424430A CN201910680134.5A CN201910680134A CN110424430A CN 110424430 A CN110424430 A CN 110424430A CN 201910680134 A CN201910680134 A CN 201910680134A CN 110424430 A CN110424430 A CN 110424430A
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China
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well
hole
deep
dewatering
dewatering well
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Inventor
高凯凯
高书义
冯超强
陈芳
努尔麦麦提·阿卜力米提
蒲荣泽
刘博�
马峥
杨秋菊
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Xinjiang Communications Construction Group Co Ltd
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Xinjiang Communications Construction Group Co Ltd
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Priority to CN201910680134.5A priority Critical patent/CN110424430A/en
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D19/00Keeping dry foundation sites or other areas in the ground
    • E02D19/06Restraining of underground water
    • E02D19/10Restraining of underground water by lowering level of ground water

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)

Abstract

The embodiment provides a kind of deep basal pit powder land floor Deep Pumped Wells construction method and its applications, are related to transport development construction field.The construction method, comprising: be drilled with multiple outer dewatering well in hole outside foundation pit, dewatering well in multiple holes is drilled in foundation pit;Multiple well casings are transferred respectively into dewatering well in corresponding outer dewatering well in hole and hole and form well casing and hole outer well tube in corresponding hole.The application carries out precipitation by combining dewatering well in outer dewatering well in hole and hole, it effectively prevents when light well point is unable to satisfy precipitation requirement, it is continuously increased the increase of well point caused by the quantity of light well point, the increase of shoveling amount and so on, pass through the combination of the outer precipitation in cheating and hole, the underground water in the soil body within the scope of effective drainage excavation of foundation pit facilitates construction equipment and the worker construction operation in cheating.

Description

Deep basal pit powder land floor Deep Pumped Wells construction method and its application
Technical field
The present invention relates to transport development construction fields, drop in particular to a kind of deep basal pit powder land floor deep well points Water construction method and its application.
Background technique
To traffic route carry out work progress in, if encountering the geology on silty clay stratum, due to its stability compared with Difference for the underground water within the scope of drainage excavation of foundation pit in the soil body, and reduces lower part in subway station deep foundation pit excavation project The head height of artesian aquifer, it is ensured that the stability of foundation pit when construction, traditional water discharge method have been unable to satisfy wanting for construction It asks.If dewatering construction cannot be carried out in time, it there is also serious frost boiling, emit mud and quicksand phenomenon, dig foundation pit can not It is deep, but also will cause a large amount of soil erosions, slope instability or neighbouring ground are collapsed, also will affect when serious and nearby build Build the safety of object.
It in view of the specific geological conditions in silty clay stratum, constructs on the ground in silt, since powder land floor infiltration is difficult Degree is big, is to carry out precipitation by the way of light well point when usually constructing, by being arranged in a certain range inside and outside foundation pit Multiple light well points realize Multipoint synchronous precipitation, but are set as if it is desired to reaching preset precipitation requirement, then needing Numerous light well points, and the arrangement dispersion of light well point are set, this can cause greatly to hinder to construction in hole, while light After the quantity of type well point is excessive, need that suction pump is arranged for each light well point, and to the situation of drawing water of each light well point It is observed, this undoubtedly increases equipment cost and cost of labor.
In consideration of it, special propose the application.
Summary of the invention
The purpose of the present invention includes, for example, a kind of deep basal pit powder land floor Deep Pumped Wells construction method is provided, Displacement is big, and precipitation is deep, can underground water within the scope of drainage excavation of foundation pit in the soil body, facilitate construction equipment and worker to exist Construction operation in cheating.
Another object of the present invention includes, such as provides above-mentioned deep basal pit powder land floor Deep Pumped Wells construction method In the application in Deep Pumped Wells engineering, the design and construction decision for similar regional engineering provides reference.
The embodiment of the present invention this can be implemented so that
In a first aspect, the embodiment of the present invention provides a kind of deep basal pit powder land floor Deep Pumped Wells construction method, comprising:
It is drilled with multiple outer dewatering well in hole outside foundation pit, dewatering well in multiple holes is drilled in the foundation pit;
Multiple well casings are transferred respectively into dewatering well in the corresponding outer dewatering well in hole and the hole formed it is corresponding Well casing and hole outer well tube in cheating.
In alternative embodiments, the section of the foundation pit is rectangle, and the outer dewatering well in hole is along foundation pit periphery It is distributed in a ring, dewatering well is distributed along the middle line of the length direction of the foundation pit in the hole.
In alternative embodiments, the well casing includes sequentially connected well head section, non-porous pipeline section, drainage from top to bottom Pipeline section and precipitating pipeline section, the well head section 0.3-0.5m above ground level, the drainage pipeline section offer directly along its length Diameter is multiple circular holes of 8-12mm, the sealed bottom of the precipitating pipeline section;
Preferably, multiple circular holes carry out array row along the drainage pipeline section with (40-60) mm × (40-60) mm Cloth;
Preferably, it is coated with multistorey strainer mesh on the outside of the drainage pipeline section, and is wound with iron wire;
Preferably, the strainer is the nylon leaching net of 50-70 mesh, and the iron wire is with the spacing spiral winding of 90-110mm.
In alternative embodiments, depth, respectively 24-26m and 30-32m there are two types of the outer dewatering well in hole tools, In, the outer dewatering well in hole that depth is 30-32m is set to bottom of foundation ditch, and there are the regions of multilayer circle gravel artesian aquifer;
Preferably, it is placed in the drainage pipeline section buried depth 3-30m of the well casing in the outer dewatering well in hole that depth is 30-32m;
Preferably, it is placed in the drainage pipeline section buried depth 3-24m of the well casing in the outer dewatering well in hole that depth is 24-26m.
In alternative embodiments, the spacing of dewatering well is 21.0~22.0m in the hole;
Preferably, the depth of dewatering well is 24-26.0m in the hole;
Preferably, it is placed in the drainage pipeline section buried depth 3-24m of the well casing in the hole in dewatering well.
In alternative embodiments, foundation pit area and single sinking area, foundation pit area and list are calculated by area-method Quantity of the ratio of well precipitation area as dewatering well in the hole;
The calculation formula of the quantity of dewatering well in the hole are as follows: n=A/a
In formula: n-- well number (mouth);
A-- foundation pit area (m2);
A-- single sinking area (m2);
Preferably, the quantity of dewatering well is 10-12 mouthfuls in the hole.
In alternative embodiments, by generally to change big well to calculate the water outflow from single well of big well, as base pit dewatering Total yield;Quantity of the ratio of total yield and dewatering well water outflow from single well as the outer dewatering well in hole, wherein always gush The calculation formula of water is as follows:
In formula: the total yield (m of Q-- base pit dewatering3/d);
K-- infiltration coefficient (m/d);
H0-- phreatic aquifer thickness (m);
s0-- Water Level in Foundation Pit drawdown (m);
R-- Rainfall Influence radius (m);
r0-- the radius (m) for the precipitation gang of wells institute's envelope surface product equivalent circular being evenly arranged along foundation pit periphery;
The calculation formula of the quantity of outer dewatering well in hole are as follows: N=Q/q, wherein q-- water outflow from single well (m3/d);
Preferably, the quantity of the outer dewatering well in hole is 30-35 mouthfuls.
In alternative embodiments, the section of the foundation pit is rectangle, and the outer dewatering well in hole is along foundation pit periphery It is distributed in a ring, dewatering well is distributed along the middle line of the length direction of the foundation pit in the hole.
In alternative embodiments, by the way that groundwater flow direction is divided into upstream and downstream, wherein upstream it is described The spacing of outer dewatering well in hole is 15.5-16.5m, and the spacing of the outer dewatering well in hole in downstream is 17.5-18.5m.
In alternative embodiments, the hole outer well tube is pvc pipe, and the diameter of the hole outer well tube is 240-260mm, Wall thickness is 5-7mm;
Preferably, well casing is steel well casing in the hole, and the diameter of well casing is 263-283mm, wall thickness 2- in the hole 4mm。
Second aspect, the embodiment of the present invention provide such as the described in any item deep basal pit powder land floor deep-wells of aforementioned embodiments Application of the well-points dewatering construction method in Deep Pumped Wells engineering, the infiltration coefficient of the Deep Pumped Wells engineering are 20 ~250m/d;
Preferably, the soil property of the Deep Pumped Wells engineering is sandy soil or silt;
Preferably, the precipitation depth of the Deep Pumped Wells engineering is 15~50m.
The beneficial effect of the embodiment of the present invention includes, for example: the application and passes through dewatering well knot by outer dewatering well in hole and in cheating It closes and carries out precipitation, effectively prevent being continuously increased the quantity of light well point when light well point is unable to satisfy precipitation requirement and leading The increase of the well point of cause, the increase of shoveling amount and so on, pass through the combination of the outer precipitation in cheating and hole, effective drainage foundation pit The underground water in the soil body in range is excavated, construction equipment and the worker construction operation in cheating are facilitated;Reduce the soil body in cheating Water content improves soil strength in cheating, and reduces the deflection of bottom heave and building enclosure, prevents from cheating outer earth's surface Excessive Settlement; Soil body stability in digging process is improved, prevents soil layer from longitudinally coming down;The head height for reducing lower part artesian aquifer in time, prevents The only prominent generation gushed of bottom of foundation ditch, it is ensured that the stability of base plate of foundation pit when construction.
Detailed description of the invention
In order to illustrate the technical solution of the embodiments of the present invention more clearly, below will be to needed in the embodiment attached Figure is briefly described, it should be understood that the following drawings illustrates only certain embodiments of the present invention, therefore is not construed as pair The restriction of range for those of ordinary skill in the art without creative efforts, can also be according to this A little attached drawings obtain other relevant attached drawings.
Fig. 1 is the hydrogeological plan view of the application construction area;
Fig. 2 is the hydrogeological profile of the application construction area;
Fig. 3 is the precipitation floor plan of deep basal pit powder land floor Deep Pumped Wells construction method provided by the present application;
Fig. 4 is the partial enlarged view in Fig. 3 at A;
Fig. 5 is the dewatering and drainage pipe network figure of deep basal pit powder land floor Deep Pumped Wells construction method provided by the present application;
Fig. 6 is the process flow chart of deep basal pit powder land floor Deep Pumped Wells construction method provided by the present application;
Fig. 7 is that the air compressor machine well-flushing principle of deep basal pit powder land floor Deep Pumped Wells construction method provided by the present application is shown It is intended to;
Fig. 8 is that the drainage well of deep basal pit powder land floor Deep Pumped Wells construction method provided by the present application draws water signal Figure.
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention In attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is A part of the embodiment of the present invention, instead of all the embodiments.The present invention being usually described and illustrated herein in the accompanying drawings is implemented The component of example can be arranged and be designed with a variety of different configurations.
Therefore, the detailed description of the embodiment of the present invention provided in the accompanying drawings is not intended to limit below claimed The scope of the present invention, but be merely representative of selected embodiment of the invention.Based on the embodiments of the present invention, this field is common Technical staff's every other embodiment obtained without creative efforts belongs to the model that the present invention protects It encloses.
It should also be noted that similar label and letter indicate similar terms in following attached drawing, therefore, once a certain Xiang Yi It is defined in a attached drawing, does not then need that it is further defined and explained in subsequent attached drawing.
In the description of the present invention, it should be noted that if there is the side of the instructions such as term " on ", "lower", "inner", "outside" Position or positional relationship be based on the orientation or positional relationship shown in the drawings or the invention product using when the side usually put Position or positional relationship, are merely for convenience of description of the present invention and simplification of the description, rather than the device or member of indication or suggestion meaning Part must have a particular orientation, be constructed and operated in a specific orientation, therefore be not considered as limiting the invention.
In addition, being only used for distinguishing description if there is term " first ", " second " etc., it is not understood to indicate or imply phase To importance.
It should be noted that in the absence of conflict, the feature in the embodiment of the present invention can be combined with each other.
Embodiment
This application provides a kind of deep basal pit powder land floor Deep Pumped Wells construction methods, and it is viscous to be particularly suitable for silty Soil layer.
The application is specifically said using Urumchi rail transit Line 2 first stage of the project level land way station as typical case It is bright.Please refer to Fig. 1 and Fig. 2, way station geology in Urumchi rail transit Line 2 first stage of the project level land is mainly silty clay Layer, stability is poor, and base area is surveyed there are artesian water, diving in report display stratum, and water-bearing layer distribution is discontinuous.Diving is main It buries in silt, gravel concentration about 15%, part reachable 20%, top plate buried depth 1.2-4m, thickness about 14-17m.Depth to water 3-5m, fixed level absolute altitude 854.6-856.1m, convert water yield 454.102m3/ d, watery is medium, infiltration coefficient 7.87m/ D, experience specific yield 0.05.Artesian aquifer is mainly distributed on the station south position 120m long, and station the north partial region is in saturating Mirror body exists, water-bearing layer lithology be the 4th be gravel layer, top plate buried depth 17.5-19m, absolute altitude 840.7-842.28m, bottom plate buried depth 19.4-25m, absolute altitude 834.6-842.6m, water-bearing layer thickness 1.8-3.7m.Depth to water 1.38m, absolute altitude 858.4m, conversion are gushed Water 235.168m3/ d, watery is medium, infiltration coefficient 4.34m/d.
Since way station pattern foundation pit supporting structure in level land usesSpacing 1400mm reinforced concrete bored pile, goes along with sb. to guard him There are gaps between stake, do not form closed water-stop curtain.By the demonstration repeatedly of applicant, it is found by the applicant that using existing Precipitation method (Application of light well point precipitation) arranged along fender post outer boundary, to block or weaken inside and outside foundation pit diving and artesian water The mode of hydraulic connection carries out precipitation.But according to Pumping Test Data early period, when cheating outer multi-well pumping, interior observation Well Water Level is cheated Drawdown is smaller, is still unable to satisfy the demand of precipitation, and therefore, the application is using deep well points in cheating outer Deep Pumped Wells and cheating The method that precipitation combines handles the underground water within the scope of main structure foundation pit construction, by the way that dewatering well is arranged in hole Pipe is realized that drainage cheats the effect of interior soil body underground water, is gone on smoothly convenient for earth excavation construction.
Next it will be specifically described the deep basal pit powder land floor Deep Pumped Wells construction method of the application, referring to Fig. 6, The construction method of the application specifically includes the following steps:
S1: multiple outer dewatering well in hole are drilled with outside foundation pit;
By precalculating quantity, spacing and the depth of calculating outer dewatering well in hole to determine the arrangement feelings of outer dewatering well in hole Condition.
Specifically, by generally to change total yield of the big well to calculate the water outflow from single well of big well, as base pit dewatering;Always Quantity of the ratio of water yield and dewatering well water outflow from single well as outer dewatering well in hole.
Specifically, the precipitation gang of wells institute's envelope surface being evenly arranged along foundation pit periphery product generalization is done into the big well of a bite, calculates this The water outflow from single well of big well, the as total yield of base pit dewatering.
Water yield of well under being drawn water using the disturbed wells in place bailing test achievement early period is as this engineering dewatering The expection dewatering well water yield of well of operation phase.
Quantity of the ratio of total yield and dewatering well water outflow from single well as outer dewatering well in hole.
(1) calculating process of the quantity of outer dewatering well in hole is as follows:
Foundation pit total yield is calculated using following formula:
In formula: the total yield (m of Q-- base pit dewatering3/d);
K-- infiltration coefficient (m/d), integrates the preceding result of bailing test several times and surveying report takes 3.0m/d in detail;
H0-- phreatic aquifer thickness (m) takes 20.0m;
s0-- Water Level in Foundation Pit drawdown (m) takes 16.0m;
R-- Rainfall Influence radius (m) takes 140.0m according to bailing test result;
r0-- the radius (m) for the precipitation gang of wells institute's envelope surface product equivalent circular being evenly arranged along foundation pit periphery;
It is therefore counted below in view of Urumchi rail transit Line 2 first stage of the project level land way station is directed in the application According to the specific example for being Urumchi rail transit Line 2 first stage of the project level land way station, by the construction method application of the application When to other same type building sites, can the actual conditions in concrete foundation place calculate and value.
It is 3.0m/d specific in the present embodiment, integrating the preceding result of bailing test several times and surveying report in detail to take K;Take H0For 20.0m;Take s0For 16.0m;Taking R according to bailing test result is 140.0m;It is rectangle foundation pit by foundation pit in this present embodiment, For rectangle foundation pit r0It can be by formula r0=ξ (l+b)/4 is calculated, and l is foundation pit length (m) herein;B is foundation pit width (m);ξ is foundation pit Shape correlation coefficients, ξ=1.05 of tabling look-up to obtain.r0By calculating to obtain 70.35m.
It substitutes into all data and calculates to obtain Q=3288.4m3/d。
Water outflow from single well q takes 100.0m according to the result that multi-well pumping is tested3/d。
Calculate 33 mouthfuls of number of dewatering well N=Q/q ≈.
It is calculated according to above, in conjunction with foundation pit supporting construction feature, this programme arranges 33 mouthfuls of precipitation pipe well altogether on the outside of foundation pit, Number S1~S33.Specific well location is detailed in Fig. 3, Fig. 4 and Fig. 5.
It should be understood that the quantity of outer dewatering well in hole can be carried out according to the actual conditions of construction site in other similar projects Adjustment.
(2) determination of the spacing of outer dewatering well in hole
According to region hydrogeology condition, underground latent water and artesian water are fed northeastward by southwest, by place along underground water Middle line on runoff direction is divided into two parts, and southwestward is upstream, and northeastward is downstream.It is closeer according to upstream dewatering well, The thinner principle in downstream determines that the well spacing of upstream is 15.5-16.5m, and preferably 16.0m, the well spacing in downstream is 17.5- 18.5m, preferably 18.0m.
(3) determination of the depth of outer dewatering well in hole
According to the earth formation of place different zones and the buried depth situation in each water-bearing layer, determine that precipitation well depth is 24-26m With two kinds of 30-32m, it is preferable that the depth of outer dewatering well in hole is 25m and two kinds of 31m.Wherein, foundation pit the north place foundation pit bottom surface In following 15.0m depth bounds (18.5~31.6m of buried depth) there are multilayer circle gravel artesian aquifer.To reduce its artesian head, Reduce its influence to hole bottom, 3 mouthfuls of dewatering wells in one's respective area are deepened to 30-32m, pipeline section buried depth 3.0-30.0m is filtered;Its Remaining well depth 25.0m filters pipeline section buried depth 3.0-24.0m.Consider the factors such as economic, feasible, outer dewatering well in hole pipe uses pvc pipe.
S2: dewatering well in multiple holes is drilled in foundation pit.
Need to precalculate quantity, spacing and the depth of dewatering well in cheating when being drilled with and cheating interior dewatering well.
According to bailing test early period, when the outer group wells of foundation pit persistently draws water, cheats interior inspection well SEA LEVEL VARIATION and be not obvious.Cause This, the application lays certain amount drainage precipitation pipe well in hole to meet the requirement of underground water position, is calculated using area-method true Determine dewatering well quantity.
N=A/a
In formula: n-- well number (mouth);
A-- foundation pit area (m2);
A-- single sinking area (m2), 500m is determined as according to regional experience and geological conditions2
It is calculated by above formula, the well spacing quantity in excavation of foundation pit region is as follows: excavation of foundation pit area about 5536.5m2, determine in hole 11 mouthfuls of dewatering well n=5536.5/500 ≈, number S34~S44, in multiple holes dewatering well along the length direction of foundation pit middle line It is distributed and (please refers to Fig. 3, Fig. 4 and Fig. 5), the spacing for cheating interior dewatering well is 21.0-22.0m, and the depth for cheating interior dewatering well is 24-26m (preferably 25m) filters pipeline section buried depth 3.0-24.0m.For the integrity for ensuring well casing during earth excavation, in hole Dewatering well uses the higher steel well casing of intensity.
The filtering pipeline section of dewatering well is through top powder soil horizon and lower part circle gravel artesian aquifer in cheating, in drainage cutting depth In range while diving, lower part artesian head is reduced, drainage and decompression can be played a dual role of, it is ensured that dewatering effect And the safety and stability of base plate of foundation pit.
In the application, by the way that dewatering well in multiple holes to be distributed along the middle line of the length direction of foundation pit, interior drop is cheated The spacing of well is 21.0-22.0m, and such distribution mode can guarantee to cheat what two sides of the interior dewatering well apart from foundation pit were reserved Distance is sufficient, not will receive the destruction of mechanical equipment, meanwhile, well spacing is big in the application, and it is smaller to the soil layer disturbance of foundation pit, and Conducive to the arrangement of plane, subsequent construction will not be impacted.
The precipitation operation of observation during to(for) underground water position can choose 1~2 mouthful when necessary and cheat interior dewatering well, and pause is drawn water Its water level is observed after about 12 hours, can be obtained more really and accurately mine water position data.
Specifically, drilling forms outer dewatering well in hole and the process of dewatering well in hole includes:
(1) when being drilled with to form outer dewatering well in hole, according to well point horizontal layout, pipe well points are in ring along foundation pit periphery Shape distribution, using total station measuring well location, well location measuring error is less than 30cm.Influenced by ground obstacle when the well point of laying or When execution conditions influence, scene can be appropriately adjusted.This engineering arranges 33 mouthfuls of precipitation pipe well altogether on the outside of foundation pit, between the well of upstream It is 18.0m away from the well spacing for 16.0m, downstream.Be drilled with cheat in dewatering well when, hole according to well point horizontal layout, in foundation pit Interior dewatering well is distributed along the middle line of the length direction of foundation pit, and the spacing for cheating interior dewatering well is 21.0~22.0m.
(2) drilling machine is in place and drills
Rig substructure should install firm level, hook alignment hole center, and hook, turntable, hole center should be at sight alignments.
It generally uses nature pulping to creep into when drilling, when chance layer of sand is thicker, should manually prepare mud off, mud density control System is in 1.15~1.25g/cm3.When promoting drilling tool and interim brill stopping time, full mud should be pressed in hole, prevents hole wall collapse.When necessary Heavy weight additive (such as blanc fixe) Lai Tigao mud density can be added in mud, increase drilling head of liquid, to prevent drilling from gushing Water.
Outer dewatering well in hole depth is two kinds of 25.0m, 31.0m.(buried depth 18.5- in 15.0m depth bounds below foundation pit bottom surface 31.6m) there are multilayer circle gravel artesian aquifers, to reduce its artesian head, reduce its influence to hole bottom, will be in one's respective area 3 mouthfuls outer dewatering well in hole (S16~No. S18) is deepened to 31.0m, and pipeline section buried depth 3.0-30.0m is filtered;Remaining well depth 25.0m, filtering Pipeline section buried depth 3.0-24.0m.
(3) borehole cleaning changes slurry
After drilling drilling to designed elevation, by drilling tool lifting at away from bottom hole 20-30cm, slush pump borehole cleaning is started, with clear Except inner hole deposition slag, inner hole deposition silt should be less than 20cm.
Borehole cleaning is changed slurry and is constructed using direct circulation method, using the viscous force of mud colloidality, the flushing cinder or boring mud in stake holes Adhesive tape along mud flowing be discharged stake holes.The specific gravity for strictly controlling mud, makes density domination in 1.10g/cm3Left and right is to balance Soil pressure and water pressure.
It should be understood that before being drilled, it should carry out conventional smooth location, connect the power supply of drilling machine while also wrapping It includes and excavates corresponding mud ditch and sedimentation basin, after then band drilling machine is in place, it can start to drill.
S3: multiple well casings are transferred respectively and form well in corresponding hole into dewatering well in corresponding outer dewatering well in hole and hole Pipe and hole outer well tube.
Well casing in the application includes sequentially connected well head section, non-porous pipeline section, drainage pipeline section and precipitating from top to bottom Pipeline section, in the present embodiment, well head section, non-porous pipeline section, drainage pipeline section and precipitate pipeline section diameter it is identical.Wherein, well head section is high Ground 0.3-0.5m out, to prevent mud and surface waste water from flowing into well outside pipe.Drainage pipeline section offers along its length Diameter is multiple circular holes of 8-12mm, and multiple circular holes carry out array along drainage pipeline section with (40-60) mm × (40-60) mm Arrangement;It is coated with multistorey strainer mesh on the outside of the drainage pipeline section, and is wound with iron wire;Preferably, strainer is the nylon of 50-70 mesh Strainer, iron wire is with the spacing spiral winding of 90-110mm.The sealed bottom for precipitating pipeline section, the length for precipitating pipeline section is 1m.
Preferably, in the application, consider the factors such as economic, feasible, hole outer well tube is pvc pipe, and the diameter for cheating outer well tube is 240-260mm, wall thickness 5-7mm.
It preferably, is the integrity of well casing during ensuring earth excavation in the application, cheating interior well casing is that intensity is higher Steel well casing, the diameter for cheating interior well casing is 263-283mm, wall thickness 2-4mm.
When placing well casing, in the present embodiment, down tube is carried out using lifting method, specifically, using hoist engine or hanging Vehicle, by root, tripping in is connected in order, and well casing should be connected firmly, seal, is waterproof.When down tube, pays attention to gently proposing slow play, make every effort to well casing The centralizer that a set of diameter is less than aperture 5cm is respectively arranged in arranged orthogonal, filter pipe upper and lower ends, to guarantee that it is placed in the middle.Tube top portion 30cm-50cm higher than nature ground or so prevents sewage from entering in well.When top hole wall undergauge or bottom hole are silted up, in Ying Xiangkong Water filling, is slowly put into, and forbids lifting and impacting by force up and down.
S4: it is backfilled between the tube wall of hole outer well tube and the hole wall of outer dewatering well in hole, while in the pipe for cheating interior well casing It is backfilled between wall and the hole wall for cheating interior dewatering well.
Filling gravel filtrate is layered with spade between well casing and hole wall.Partial size should be greater than the aperture of strainer, and generally 3mm~ 8mm bird's-eye gravel.The completion of filtrate one-time continuous is filled out, fills out the bottom of to well head and divides into position, top uses the clay without sandstone to seal. During delivering filtrate, answers surrounding uniformly to put into gravel material and survey the height that feeds intake when throwing, until gravel material tripping in predetermined position is Only.
Gravel material Duan Shangyong clay ball sealing, sealing height 6.0m.Sealing section above section local sticky earthen backfill, decentralization Speed should not be too fast.
Well head closing, borehole wall periphery are generally closed using tonerde or cement slurry, and depth is not less than 2.0m.
S5: well-flushing is carried out to well casing in hole outer well tube and hole after backfill.
Using air compressor machine well-flushing method, well-flushing answers observed stage and water yield to change, well-flushing in the process until water sand removal is net Principle sees Fig. 7.
S6: pumping equipment is then installed and is drained.
After well construction, tripping in water pump carries out examination and draws water, to check into well quality.To avoid drawing water, facility is touched It hits, roll impaired, pumping equipment must be identified.The water that well-flushing and precipitation are discharged when running, is discharged into field by pipeline or open channel In outer municipal pipeline, principle of drawing water sees Fig. 8.
The application is by above-mentioned deep basal pit powder land floor Deep Pumped Wells construction method by that will cheat in outer precipitation and hole The mode that precipitation combines effectively prevents being continuously increased the number of light well point when light well point is unable to satisfy precipitation requirement The increase of well point caused by amount, the increase of shoveling amount, in the application by Deep Pumped Wells in cheating and The combination of outer Deep Pumped Wells is cheated, outer dewatering well in hole is 33 mouthfuls in the application, and outer dewatering well in hole is along foundation pit periphery It is distributed in a ring, can be effectively reduced the underground water in hole, while can also effectively avoid cheating outer underground water to the supply in hole, from And outer underground water barrier will be cheated, guarantee the safety constructed in hole.In addition, dewatering well is 11 mouthfuls in hole in the application, and edge The length direction of foundation pit middle line distribution, not only play the role of drainage mine water, while also will not influence in hole The construction of big machinery facilitates construction equipment (especially excavator) and the worker construction operation in cheating;Hole is reduced simultaneously Interior water content of soil improves soil strength in cheating, and reduces the deflection of bottom heave and building enclosure, prevents from cheating outer earth's surface excess Sedimentation;Soil body stability in digging process is improved, prevents soil layer from longitudinally coming down;The head for reducing lower part artesian aquifer in time is high Degree prevents the prominent generation gushed of bottom of foundation ditch, it is ensured that the stability of base plate of foundation pit when construction.In addition, the application is also by above-mentioned deep base Hole powder land floor Deep Pumped Wells construction method has been successfully applied in multiple real cases.
Specifically, the application is in Urumqi City's rail transit Line 2 first stage of the project civil construction B-05 contract section, crow It is applied in the city Lu Muqi rail transit Line 2 first stage of the project B-03 bid section engineering, it is consistent with management to obtain owner Favorable comment.
Urumqi City's rail transit Line 2 first stage of the project civil construction B-05 contract section: this project site is located at Xinjiang Urumqi City, this engineering are made of one section of a station, are respectively as follows: level land way station, level land way station~nine gulf station section.Level land Way station geology is mainly silty clay stratum, and stability is poor, base area survey report display stratum in there are artesian water, diving, Water-bearing layer distribution is discontinuous.Diving mainly buries in silt, and watery is medium, infiltration coefficient 7.87m/d, experience specific yield 0.05.Artesian aquifer is mainly distributed on the station south position 120m long, and station the north partial region exists in lenticular body, aqueous Thickness 1.8~3.7m of degree, watery is medium, infiltration coefficient 4.34m/d.Plan was gone into operation on October 01st, 2016, be completed in On December 31st, 2019.
Urumqi City's rail transit Line 2 first stage of the project B-03 bid section: this project site is located at Xinjiang Urumqi city, The beginning and the end mileage is YCK22+178.184~YCK24+127.815 (ZCK22+178.184~ZCK24+127.815), and it is big to be divided into two Part: Huashan street station, the Urumchi Station~Huashan section Jie Zhan.It is Holocene series element that master stratum, which is the 4th, in the yard ground of Huashan street It bankets, rush proluvial clayey silt, sandy silt, circle gravel, cobble, stability is poor.This place surface water derives from local earth's surface Underground water overflows band and wound reaches the reservoir of garden No. 1, No. 2.Groundwater type is mainly pore ground water, Bedrock Crevice Water, construction Crevice water.In the 4th system and basement rock contact in neighbouring mid Pleistocene series stratum, Bedrock Crevice Water is distributed in main preservation of diving under water In the basement rock weathered layer on basement rock surface layer, water is smaller, and structural fissured water is distributed mainly in nine gulf fractures.Plan go into operation in It is completed on December 31st, 2019 on October 01st, 2016.
Urumqi City's rail transit Line 2 first stage of the project civil construction B-05 contract section engineering uses " deep basal pit silt Stratum Deep Pumped Wells construction method " construction, economical, societal benefits are prominent.In terms of economic benefits, Comprehensive Correlation is traditional The features such as dewatering construction, the application have displacement big, and well spacing is big, and precipitation is deep, and well point setting is few, shortens the construction period, Reduce construction cost;In addition, well-point pipe uses steel pipe, pvc pipe, it whole can eradicate out and reuse, precipitation average cost is low, Resource is saved, cost-effective and environmentally friendly.In terms of social benefit, present application addresses northwest arid area (especially Xinjiang regions) The problem of deep basal pit powder land floor Deep Pumped Wells, the design and construction decision for similar regional engineering provide reference.Especially It is suitable for be 20~250m/d in infiltration coefficient, soil property is sandy soil or silt, rich groundwater, precipitation depth be 15~ In the Deep Pumped Wells engineering of 50m.
In conclusion a kind of deep basal pit powder land floor Deep Pumped Wells construction method provided in this embodiment at least has Following advantages:
The application by by outer dewatering well in hole and cheat in dewatering well combine carry out precipitation, effectively prevent light well point without When method meets precipitation requirement, it is continuously increased the increase of well point caused by the quantity of light well point, situations such as the increase of shoveling amount Generation, compare traditional precipitation (light well point) construction method, the application has displacement big, and precipitation is deep (> 15m), will dive Water pump sink to well casing bottom do not limited by suction (in the prior art, due to light well point be by foundation pit surrounding by diameter compared with Thin well casing, which is sunk to, is deeper than substrate hereinafter, then connecting using well casing top with general pipeline, utilizes pumping equipment by ground by general pipeline It is lauched and is constantly extracted out out of well casing, so that original level of ground water is reduced to substrate mode of operation below and carry out precipitation, due to light-duty Well point is to carry out suction underground water using vacuum principle, and suction is restricted, and depth of usually drawing water is 8m or so), draining The advantages that effect is outstanding.Well spacing is big, smaller to the soil layer disturbance of foundation pit, and is conducive to the arrangement of plane.It is comprehensive with other methods Compare well spacing and displacement, hole is outer in the application only needs 33 mouthfuls of dewatering wells, while only needing 11 mouthfuls of dewatering wells in hole, compared to existing For carrying out precipitation by arrangement light well point in technology, well point setting is greatly reduced, shoveling amount is decreased, reduces and apply Expenses of labour is used and energy consumption, and environmental benefit is prominent, is conducive to economize on resources.Pore-forming (well-digging) can use mechanical execution, and speed of application is fast, by The precipitation of dewatering well is big in outer dewatering well in hole and hole in the application, can effectively ensure the duration.Well point production, drop Wetting system and operating procedure are relatively simple, and speed of application is fast.Individual well independently working is only limitted to single if immersible pump breaks down Well point, replacement is convenient, is easily installed maintenance, the normal operation of precipitation system is effectively guaranteed.Well casing uses steel pipe, pvc pipe, It whole can eradicate out and reuse, precipitation average cost is low, and energy-saving and environmental protection benefit is prominent.Use scope is wide, can be according to specifically Matter condition, which is adjusted, to be used.
The above description is merely a specific embodiment, but scope of protection of the present invention is not limited thereto, any In the technical scope disclosed by the present invention, any changes or substitutions that can be easily thought of by those familiar with the art, all answers It is included within the scope of the present invention.Therefore, protection scope of the present invention should be with the scope of protection of the claims It is quasi-.

Claims (10)

1. a kind of deep basal pit powder land floor Deep Pumped Wells construction method characterized by comprising
It is drilled with multiple outer dewatering well in hole outside foundation pit, dewatering well in multiple holes is drilled in the foundation pit;
Multiple well casings are transferred respectively into dewatering well in the corresponding outer dewatering well in hole and the hole and are formed in corresponding hole Well casing and hole outer well tube.
2. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that the base The section in hole is rectangle, and the outer dewatering well in hole is distributed in a ring along foundation pit periphery, and dewatering well is along described in the hole The middle line of the length direction of foundation pit is distributed.
3. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that the well Pipe includes that sequentially connected well head section, non-porous pipeline section, drainage pipeline section and precipitating pipeline section, the well head section are higher by ground from top to bottom Face 0.3-0.5m, the drainage pipeline section offer multiple circular holes that diameter is 8-12mm, the precipitating pipeline section along its length Sealed bottom;
Preferably, multiple circular holes carry out array arrangement along the drainage pipeline section with (40-60) mm × (40-60) mm;
Preferably, it is coated with multistorey strainer mesh on the outside of the drainage pipeline section, and is wound with iron wire;
Preferably, the strainer is the nylon leaching net of 50-70 mesh, and the iron wire is with the spacing spiral winding of 90-110mm.
4. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 2, which is characterized in that the hole There are two types of depth, respectively 24-26m and 30-32m for outer dewatering well tool, wherein depth is that the outer dewatering well in hole of 30-32m is set Being placed in bottom of foundation ditch, there are the regions of multilayer circle gravel artesian aquifer;
Preferably, it is placed in the drainage pipeline section buried depth 3-30m of the well casing in the outer dewatering well in hole that depth is 30-32m;
Preferably, it is placed in the drainage pipeline section buried depth 3-24m of the well casing in the outer dewatering well in hole that depth is 24-26m.
5. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 2, which is characterized in that the hole The spacing of interior dewatering well is 21.0~22.0m;
Preferably, the depth of dewatering well is 24-26.0m in the hole;
Preferably, it is placed in the drainage pipeline section buried depth 3-24m of the well casing in the hole in dewatering well.
6. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that pass through face The ratio of area method calculating foundation pit area and single sinking area, foundation pit area and single sinking area is as dewatering well in the hole Quantity;
The calculation formula of the quantity of dewatering well in the hole are as follows: n=A/a
In formula: n-- well number (mouth);
A-- foundation pit area (m2);
A-- single sinking area (m2);
Preferably, the quantity of dewatering well is 10-12 mouthfuls in the hole.
7. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that by with Generally change big well to calculate the water outflow from single well of big well, as the total of base pit dewatering
Water yield;Quantity of the ratio of total yield and dewatering well water outflow from single well as the outer dewatering well in hole, wherein always gush The calculation formula of water is as follows:
In formula: the total yield (m of Q-- base pit dewatering3/d);
K-- infiltration coefficient (m/d);
H0-- phreatic aquifer thickness (m);
s0-- Water Level in Foundation Pit drawdown (m);
R-- Rainfall Influence radius (m);
r0-- the radius (m) for the precipitation gang of wells institute's envelope surface product equivalent circular being evenly arranged along foundation pit periphery;
The calculation formula of the quantity of outer dewatering well in hole are as follows: N=Q/q, wherein q-- water outflow from single well (m3/d);
Preferably, the quantity of the outer dewatering well in hole is 30-35 mouthfuls.
8. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that pass through by Groundwater flow direction is divided into upstream and downstream, wherein the spacing of the outer dewatering well in hole of upstream is 15.5-16.5m, downstream The outer dewatering well in hole spacing be 17.5-18.5m.
9. deep basal pit powder land floor Deep Pumped Wells construction method according to claim 1, which is characterized in that the hole Outer well tube is pvc pipe, and the diameter of the hole outer well tube is 240-260mm, wall thickness 5-7mm;
Preferably, well casing is steel well casing in the hole, and the diameter of well casing is 263-283mm, wall thickness 2-4mm in the hole.
10. if the described in any item deep basal pit powder land floor Deep Pumped Wells construction methods of claim 1-9 are in deep well points Application in dewatering project, which is characterized in that the infiltration coefficient of the Deep Pumped Wells engineering is 20~250m/d;
Preferably, the soil property of the Deep Pumped Wells engineering is sandy soil or silt;
Preferably, the precipitation depth of the Deep Pumped Wells engineering is 15~50m.
CN201910680134.5A 2019-07-26 2019-07-26 Deep basal pit powder land floor Deep Pumped Wells construction method and its application Pending CN110424430A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113605428A (en) * 2021-07-30 2021-11-05 中煤长江基础建设有限公司 Method for rapidly treating soft construction surface of pile foundation in sandy soil area
CN114703880A (en) * 2022-04-28 2022-07-05 华能鹤岗发电有限公司 Method for lowering water level of fan foundation of 200MW wind power project
CN114934530A (en) * 2022-04-07 2022-08-23 生态环境部南京环境科学研究所 Polluted underground water treatment method for building construction polluted soil
CN115492142A (en) * 2022-06-25 2022-12-20 中建五局土木工程有限公司 Monitoring and control system for uneven dewatering and draining of large-scale deep foundation pit

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
卢春房: "《隧道工程》", 30 April 2015, 中国铁道出版社 *
李长山: "深基坑降水对基坑稳定影响的分析", 《土工基础》 *
汤伟等: "《工程施工与质量简明手册丛书 城市管廊》", 31 October 2018, 中国建材工业出版社 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113605428A (en) * 2021-07-30 2021-11-05 中煤长江基础建设有限公司 Method for rapidly treating soft construction surface of pile foundation in sandy soil area
CN114934530A (en) * 2022-04-07 2022-08-23 生态环境部南京环境科学研究所 Polluted underground water treatment method for building construction polluted soil
CN114703880A (en) * 2022-04-28 2022-07-05 华能鹤岗发电有限公司 Method for lowering water level of fan foundation of 200MW wind power project
CN115492142A (en) * 2022-06-25 2022-12-20 中建五局土木工程有限公司 Monitoring and control system for uneven dewatering and draining of large-scale deep foundation pit
CN115492142B (en) * 2022-06-25 2024-04-09 中建五局土木工程有限公司 Monitoring and control system for non-uniform water lowering and draining of large deep foundation pit

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