CN110158579A - A kind of bored pile construction method - Google Patents
A kind of bored pile construction method Download PDFInfo
- Publication number
- CN110158579A CN110158579A CN201910344873.7A CN201910344873A CN110158579A CN 110158579 A CN110158579 A CN 110158579A CN 201910344873 A CN201910344873 A CN 201910344873A CN 110158579 A CN110158579 A CN 110158579A
- Authority
- CN
- China
- Prior art keywords
- conduit
- casing
- bored pile
- concrete
- construction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/22—Piles
- E02D5/34—Concrete or concrete-like piles cast in position ; Apparatus for making same
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D5/00—Bulkheads, piles, or other structural elements specially adapted to foundation engineering
- E02D5/66—Mould-pipes or other moulds
- E02D5/68—Mould-pipes or other moulds for making bulkheads or elements thereof
Landscapes
- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Piles And Underground Anchors (AREA)
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
Abstract
The invention discloses a kind of bored pile construction methods, characterized by the following steps: preparation of construction, shield-tube embedment, clay pulping, drilling and forming hole, borehole cleaning, lift steel reinforcement cage, conduit is set up, secondary pile hole cleaning, filling concrete, remove conduit, remove casing and drilling machine displacement, implementation through the invention, the construction of pile foundation can be gone on smoothly under conditions of the complicated geologies such as mountain area, pass through the safeguard procedures such as casing when construction, it prevents from collapsing in stake holes, improve the safety and construction efficiency of construction, cast-in-situ bored pile can effectively control settlement of foundation, to generate consolidation effect to soil layer, so that pile foundation is reliable and stable.
Description
Technical field
The invention belongs to building engineering construction method field more particularly to a kind of bored pile construction methods.
Background technique
Make in the area construction bridge of the complex geologic conditions such as some mountain areas, in order to guarantee the stabilization of bridge, bridge pier needs ground
Face direct requirement is attached by pile foundation, and in the case where the complexity of mountain area geology rock stratum, slope is relatively steep in length and breadth in mountain area, earth's surface
The factors such as weathering, it is stronger to act on, job location height above sea level, and relative relief is big cause site operation difficult, influence pile foundation
Construction speed and efficiency, and the construction speed of pile foundation influences whether the construction speed of Bridge Project, it is therefore desirable to a kind of drilling
Cast-in-place pile construction method can carry out the construction of pile foundation under the geological conditions of mountain area complexity.
Summary of the invention
In order to solve the above technical problems, can solve existing skill the present invention provides a kind of bored pile construction method
The low problem of art construction efficiency.
The present invention is achieved by the following technical programs.
A kind of bored pile construction method provided by the invention, it is characterised in that the following steps are included:
Levelling of the land to designed elevation is removed sundries, surface dust in work scene by S1, preparation of construction, hand fit's machinery,
And soil layer does compacting processing, does cure process within the scope of hell surrounding 2m；
S2, shield-tube embedment, casing top side location deviation need to be less than 5cm, and vertical line gradient need to be less than 1%, casing center
It is overlapped with pile center, casing height is 0.3m higher than ground to 2.5m；
S3, clay pulping excavate mud pit, produce slurry coat method using clay for preparing mud or bentonite, pulping amount is 2 to 3
The volume of concrete of stake again；
S4, drilling and forming hole drill to ground by drilling machine, drilling rod, drill bit, in drilling process, often extremely into 5m
8m checks bore diameter and vertical degree, and checks slag specimen, is checked with log sheet；
S5, borehole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes；
S6 lifts steel reinforcement cage, steel reinforcement cage is mounted in stake holes by lifting equipment；
S7, conduit are set up, and conduit is mounted in stake holes；
S8, secondary pile hole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes；
S9, filling concrete, by conduit into stake holes concrete perfusion, form pile foundation.
S10 removes conduit, and when carrying out step S9, conduit lower end is constantly lifted with the height of concrete grout, and is removed
Part on conduit, shortens catheter length；
S11 removes casing and drilling machine displacement, the casing in stake holes is removed, and drilling machine is shifted, complete cast-in-situ bored pile
Construction operation.
In step s 2, the casing with a thickness of the steel plate of 6mm to 15mm using rolling, and the internal diameter of casing is than stake diameter
Big 20cm to 40cm.
In step s3, the colloidity of the slurry coat method is greater than 95%, and sand factor is not more than 4%, relative density 1.2
To 1.4, viscosity is 16 to 28pa.s, and acidity-basicity ph value is 8~10.
In step s3, the liquid level of the slurry coat method is 1.0m higher than level of ground water to 1.5m.
It in step S3 and step S8, is sprayed using air compressor machine and carries out borehole cleaning, injection pressure is 0.8Mpa to 1Mpa, when borehole cleaning
Grout-jetting pipe need to be inserted into bottom hole.
In the step s 7, the conduit is made of more piece single tube, and single tube internal diameter is 25cm to 30cm, and every section single tube is a length of
2.5m to 3m, single tube part are connected with each other by ring flange.
In step s 9,2m to 6m in conduit Transducers Embedded in Concrete, and gradually risen with hole inner concrete face.
The beneficial effects of the present invention are: implementation through the invention, it can be suitable under conditions of the complicated geologies such as mountain area
Benefit carries out the construction of pile foundation, by safeguard procedures such as casings when construction, prevents from collapsing in stake holes, improve construction safety and
Construction efficiency, cast-in-situ bored pile can effectively control settlement of foundation, so that consolidation effect is generated to soil layer, so that pile foundation stabilization can
It leans on.
Detailed description of the invention
Fig. 1 is construction process for bored pile flow chart；
Specific embodiment
Be described further below technical solution of the present invention, but claimed range be not limited to it is described.
As shown in Figure 1, a kind of bored pile construction method, it is characterised in that the following steps are included:
Levelling of the land to designed elevation is removed sundries, surface dust in work scene by S1, preparation of construction, hand fit's machinery,
And soil layer does compacting processing, and cure process, while the accurate surveying and locating of survey crew are done within the scope of hell surrounding 2m, is accurately applied
Pile foundation center line is put, determines aperture absolute altitude.And establish 4 points of cross hairs around hole and fender pile is set, hole is checked and corrected in time
Position drift condition, bore operation elevation bench mark lead to retaining wall top by control bench mark.
S2, shield-tube embedment, casing top side location deviation need to be less than 5cm, and vertical line gradient need to be less than 1%, casing center
Be overlapped with pile center, casing height is 0.3m higher than ground to 2.5m, casing under conditions of Ordinary Work occasion and small aperture,
Steel plate using thickness not less than 6mm rolls, and under the conditions ofs deep water, complicated geological and large aperture etc., is preferably not less than using thickness
10mm steel plate rolls, and perpendicular positioning is accurate when burying casing, and top side location deviation is not more than 5cm, and vertical line gradient is little
In 1%.After actual measurement positioning, it is overlapped casing center with pile center, casing height 0.3m preferably above ground level or water surface 1.0m is extremely
2.0m should be higher than that when there is artesian water in drilling and hold hydraulic pressure water level 2.0m or more after stablizing, if pressure water head is unstable or steady
It is many to be higher by level of ground water for pressure water head after fixed, should first do test pile, identify and use the feasibility of cast-in-situ bored pile in such area.
Shield-tube embedment excavates certain depth and buries casing, buried depth is 2~4m, casing pair i.e. after stake position cross centre line is released in measurement
After position checks, in its surrounding backfill cohesive soil and compaction in layers.
S3, clay pulping excavate mud pit, produce slurry coat method using clay for preparing mud or bentonite, pulping amount is 2 to 3
The volume of concrete of stake again.
S4, drilling and forming hole drill to ground by drilling machine, drilling rod, drill bit, in drilling process, often extremely into 5m
8m checks bore diameter and vertical degree, and checks slag specimen, is checked with log sheet, rushes the wirerope of cone with casing center
Position deviation is not more than 2cm, steadily must not collide retaining wall and hole wall when going up and down conehead.Bore operation must be continuous, and bores
Hole construction note, and need that periodically drilling slurry is detected and tested, it needs to adjust at any time when undesirable, entire
In work progress, the loss of mud is smaller, and head is always ensured that in 2m to 3m, effectively prevents hole wall collapse, burying head
Phenomenon occurs, it is ensured that the hole quality and speed of fulfiling hole of drilled pile.When boring procedure such as encounters loose sand sand cobble layer, Yao Jinhang
It after retaining wall, can drill to next process, bore operation must work continuously, and must not interrupt, because extraordinary circumstances are necessary
When stopping boring, aperture should add protecting cover, and drill bit is forbidden to stay in hole, to prevent burying, be reached with drilling steel wire fathom drilling drilling depth
After design requirement, hole depth, aperture and hole shape etc. are checked, after confirmation meets design requirement, whole hole is filled in and checks card, through staying
Ground supervising engineer approves, can carry out the preparation of bottom hole cleaning and pouring underwater concrete.
S5, borehole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes.
S6 lifts steel reinforcement cage, steel reinforcement cage is mounted in stake holes by lifting equipment, steel reinforcement cage is added at the construction field (site)
Work, main reinforcement are mechanically connected with straight screw sleeve, and using being welded to connect, crane cooperation lifting is pacified for stirrup, stiffener, spacer bar
Dress.Reinforcement cage skeleton has enough rigidity and stability, to transport, lift and will not loose, deformation when concrete perfusion.
Reinforced steel is added together every 2m when production, and in skeleton upper end, hanging ring is rationally set according to actual needs.
S7, conduit are set up, and conduit is mounted in stake holes, and conduit is the important tool of concrete perfusion, this process selection
Rigid conduit, conduit setting stock chest suitable for reading and funnel.
S8, secondary pile hole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes；
S9, filling concrete, by conduit into stake holes concrete perfusion, form pile foundation, first batch of concrete be perfused and exists
Lock gate is set at conduit funnel base opening, and conduit bottom end to bottom hole spacing about 40cm, concrete pours into funnel, pushes down check (non-return) valve
It moves downward, water is extruded from tube bottom in conduit, is gradually arranged from well head to outside well, and concrete is depressed into hole by self weight and to lower punch power
Bottom, conduit length of embedment are controlled in 2~6m, and as concrete constantly pours into, hole inner concrete face is gradually risen, and hole internal water accumulation is not
Disconnected to rise, until concrete fills complete opening, mud is all discharged, after perfusion starts, it is necessary to continuously carry out in an orderly manner, shortening is torn open
Except the time of conduit then needs to reduce filling concrete speed, prevents from causing height in conduit when conduit inner concrete is discontented
Air bag is pressed, so that concrete filling is not gone down or is pressed and leaks conduit.
The calculating formula being perfused for the first time: V >=π D2(H1+H2)/4+πd2hl/4
In formula: V --- first batch of concrete requirement (m is perfused3)
D --- stake holes diameter (m)
H1 --- stake holes is down to conduit bottom end apart from (m)
H2 --- the first buried depth (m) of conduit
D --- catheter diameter (m)
H1 --- stake holes inner concrete reaches buried depth H2,
Height (m) needed for outer (or mud) pressure of conduit inner concrete column equilibration conduit, hl=H3rw/rc
In H3 --- wellhole or the depth of mud
Rw --- the severe (KN/m of water or mud in wellhole3)
The severe of rc --- concrete mix (takes 24KN, m3)
S10 removes conduit, and when carrying out step S9, conduit lower end is constantly lifted with the height of concrete grout, and is removed
Part on conduit, shortens catheter length, when conduit is promoted, holding position placed in the middle, determines conduit according to conduit buried depth
Hoisting depth, the promotion embedding depth of rear tube are 2m to 6m.
S11 removes casing and drilling machine displacement, the casing in stake holes is removed, and drilling machine is shifted, complete cast-in-situ bored pile
Construction operation will extract casing after concrete perfusion is complete, be in ground and stake top well head Integral rigid casing below,
It is extracted immediately after concrete has been perfused, more than ground, the casing that can be dismantled must be after concrete crushing strength reaches 5MPa
It could remove.
In step s 2, the casing with a thickness of the steel plate of 6mm to 15mm using rolling, and the internal diameter of casing is than stake diameter
Big 20cm to 40cm is convenient for concrete casting and removes.
In step s3, the colloidity of the slurry coat method is greater than 95%, and sand factor is not more than 4%, relative density 1.2
To 1.4, viscosity is 16 to 28pa.s, and acidity-basicity ph value is 8~10.
In step s3, the liquid level of the slurry coat method is 1.0m higher than level of ground water to 1.5m.
It in step S3 and step S8, is sprayed using air compressor machine and carries out borehole cleaning, injection pressure is 0.8Mpa to 1Mpa, when borehole cleaning
Grout-jetting pipe need to be inserted into bottom hole, and the insertion depth of Grout-jetting pipe is not in place will to be caused to spray collapse hole.
In the step s 7, the conduit is made of more piece single tube, and single tube internal diameter is 25cm to 30cm, and every section single tube is a length of
2.5m to 3m, single tube part are connected with each other by ring flange, after conduit integral raising, can remove the single tube on top, to guarantee
Normal perfusion.
In step s 9,2m to 6m in conduit Transducers Embedded in Concrete, and gradually risen with hole inner concrete face, guarantee coagulation
The quality of soil perfusion.
Claims (7)
1. a kind of bored pile construction method, it is characterised in that the following steps are included:
Levelling of the land to designed elevation is removed sundries, surface dust in work scene, and soil by S1, preparation of construction, hand fit's machinery
Layer does compacting processing, does cure process within the scope of hell surrounding 2m；
S2, shield-tube embedment, casing top side location deviation need to be less than 5cm, and vertical line gradient need to be less than 1%, casing center and stake
Center is overlapped, and casing height is 0.3m higher than ground to 2.5m；
S3, clay pulping excavate mud pit, produce slurry coat method using clay for preparing mud or bentonite, pulping amount is 2 to 3 times
The volume of concrete of stake；
S4, drilling and forming hole drill to ground by drilling machine, drilling rod, drill bit, in drilling process, often need into 5m to 8m
It checks bore diameter and vertical degree, and checks slag specimen, checked with log sheet；
S5, borehole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes；
S6 lifts steel reinforcement cage, steel reinforcement cage is mounted in stake holes by lifting equipment；
S7, conduit are set up, and conduit is mounted in stake holes；
S8, secondary pile hole cleaning, by changing slurry, taking out slurry, draw slag or the method for air compressor machine injection, to being cleaned in stake holes；
S9, filling concrete, by conduit into stake holes concrete perfusion, form pile foundation.
S10 removes conduit, and when carrying out step S9, conduit lower end is constantly lifted with the height of concrete grout, and removes conduit
Upper part, shortens catheter length；
S11 removes casing and drilling machine displacement, the casing in stake holes is removed, and drilling machine is shifted, complete bored pile construction
Operation.
2. a kind of bored pile construction method as described in claim 1, it is characterised in that: in step s 2, the casing
It is rolled using the steel plate with a thickness of 6mm to 15mm, the internal diameter of casing is 20cm bigger than stake diameter to 40cm.
3. a kind of bored pile construction method as described in claim 1, it is characterised in that: in step s3, the retaining wall
The colloidity of mud is greater than 95%, and sand factor is not more than 4%, and relative density is 1.2 to 1.4, and viscosity is 16 to 28pa.s, soda acid
Spending pH value is 8~10.
4. a kind of bored pile construction method as described in claim 1, it is characterised in that: in step s3, the retaining wall
The liquid level of mud is 1.0m higher than level of ground water to 1.5m.
5. a kind of bored pile construction method as described in claim 1, it is characterised in that: in step S3 and step S8, adopt
Carries out borehole cleaning with air compressor machine injection, injection pressure is 0.8Mpa to 1Mpa, and Grout-jetting pipe need to be inserted into bottom hole when borehole cleaning.
6. a kind of bored pile construction method as described in claim 1, it is characterised in that: in the step s 7, the conduit
It is made of more piece single tube, single tube internal diameter is 25cm to 30cm, and every section single tube a length of 2.5m to 3m, it is mutual that single tube part passes through ring flange
Connection.
7. a kind of bored pile construction method as described in claim 1, it is characterised in that: in step s 9, conduit embedment
2m to 6m in concrete, and gradually risen with hole inner concrete face.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910344873.7A CN110158579A (en) | 2019-04-26 | 2019-04-26 | A kind of bored pile construction method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910344873.7A CN110158579A (en) | 2019-04-26 | 2019-04-26 | A kind of bored pile construction method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110158579A true CN110158579A (en) | 2019-08-23 |
Family
ID=67638724
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910344873.7A Pending CN110158579A (en) | 2019-04-26 | 2019-04-26 | A kind of bored pile construction method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110158579A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111535305A (en) * | 2020-05-07 | 2020-08-14 | 中铁隧道局集团有限公司 | Construction method of cast-in-situ bored pile for air well |
| CN113216163A (en) * | 2021-04-27 | 2021-08-06 | 中铁三局集团第二工程有限公司 | Construction method for large-diameter bored pile in water to penetrate through sand layer |
| CN114738553A (en) * | 2022-04-18 | 2022-07-12 | 中建八局第二建设有限公司 | Pipeline centering positioning construction method and centering positioning device |
| CN117702727A (en) * | 2024-02-06 | 2024-03-15 | 江苏筑港建设集团有限公司 | Cast-in-place pile construction technology |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014088687A (en) * | 2012-10-29 | 2014-05-15 | Yokoyama Kiso Koji:Kk | Method for creating pile body |
| CN104153352A (en) * | 2014-07-31 | 2014-11-19 | 广西科技大学 | Karst geology rotary-drilling bored concrete pile hole forming process |
| CN106013092A (en) * | 2016-06-08 | 2016-10-12 | 深圳市宏业基基础工程有限公司 | Cast-in-situ bored pile construction method |
| CN107905118A (en) * | 2017-12-26 | 2018-04-13 | 杭州市城市建设基础工程有限公司 | Large bridge pile base construction method |
| CN108049396A (en) * | 2017-12-21 | 2018-05-18 | 中铁三局集团华东建设有限公司 | Cast-in-situ bored pile churning driven sleeve drilling construction method |
-
2019
- 2019-04-26 CN CN201910344873.7A patent/CN110158579A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2014088687A (en) * | 2012-10-29 | 2014-05-15 | Yokoyama Kiso Koji:Kk | Method for creating pile body |
| CN104153352A (en) * | 2014-07-31 | 2014-11-19 | 广西科技大学 | Karst geology rotary-drilling bored concrete pile hole forming process |
| CN106013092A (en) * | 2016-06-08 | 2016-10-12 | 深圳市宏业基基础工程有限公司 | Cast-in-situ bored pile construction method |
| CN108049396A (en) * | 2017-12-21 | 2018-05-18 | 中铁三局集团华东建设有限公司 | Cast-in-situ bored pile churning driven sleeve drilling construction method |
| CN107905118A (en) * | 2017-12-26 | 2018-04-13 | 杭州市城市建设基础工程有限公司 | Large bridge pile base construction method |
Non-Patent Citations (2)
| Title |
|---|
| 沈文军等: "《建筑施工技术》", 31 January 2017, 北京理工大学出版社 * |
| 郭发忠: "《桥梁工程技术》", 31 December 2007, 中央广播电视大学出版社 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111535305A (en) * | 2020-05-07 | 2020-08-14 | 中铁隧道局集团有限公司 | Construction method of cast-in-situ bored pile for air well |
| CN113216163A (en) * | 2021-04-27 | 2021-08-06 | 中铁三局集团第二工程有限公司 | Construction method for large-diameter bored pile in water to penetrate through sand layer |
| CN114738553A (en) * | 2022-04-18 | 2022-07-12 | 中建八局第二建设有限公司 | Pipeline centering positioning construction method and centering positioning device |
| CN117702727A (en) * | 2024-02-06 | 2024-03-15 | 江苏筑港建设集团有限公司 | Cast-in-place pile construction technology |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108086340B (en) | Open caisson construction structure and construction method thereof | |
| CN110158579A (en) | A kind of bored pile construction method | |
| CN110424381A (en) | A kind of process for rotary digging drilling hole stake | |
| CN104563098B (en) | A kind of super-large diameter all steel casing does operation pore-creating filling pile construction method | |
| CN105275381B (en) | Impact drill drilling construction method in rich water pebble layer | |
| CN106638640B (en) | Construction method without bottom concrete combined type cofferdam under the conditions of formation geology | |
| CN203846485U (en) | Long pile percussion drill hole forming construction device | |
| CN106245626A (en) | A kind of hard formation churning driven enters method | |
| CN102720186B (en) | Underwater once pouring method for variable cross-section bored cast-in-place pile | |
| CN208996025U (en) | A kind of double casing pile foundation construction structures of thick silt layer | |
| CN106836206A (en) | Casing rotary digging bore forming method | |
| CN104818712A (en) | Construction method of cast-in-situ bored pile suitable for karst cave geology | |
| CN113550340A (en) | Construction method of deepwater foundation of double-wall steel cofferdam without sealing bottom under deepwater rock entering condition | |
| CN108166483A (en) | Bored pile construction method | |
| CN109083183A (en) | Collapsible loess super long large diameter pile foundation churning driven expires hole mud wet process pore-forming technique | |
| CN103388333A (en) | Construction process for carrying out construction on interlocking pile by adopting rotary drilling rig and mud protection wall method | |
| CN112482364A (en) | Construction process of rotary digging cast-in-place pile under strong corrosive soft geological conditions in coastal region | |
| CN110284885A (en) | Shield inspection-pit construction method | |
| CN108589711A (en) | A kind of construction method of bead string type solution cavity development area fender post | |
| CN106677166A (en) | Flow construction method for forming cast-in-place bored pile for gravel-decomposed rock stratum in double-machine combined mode | |
| CN112281880A (en) | Construction method of complex stratum long spiral hole-leading inserting-driving locking opening steel pipe pile cofferdam | |
| CN107653878A (en) | Cast-in-situ bored pile is reusable to be longitudinally separated formula steel pile casting construction | |
| CN115341533A (en) | Drilling construction method for cast-in-place pile in easily collapsed stratum | |
| CN110080779A (en) | Tunnel tunnel bottom karst cave treatment construction method | |
| CN106087996B (en) | Manual digging pile construction method based on self leveling backpressure device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20190823 |
|
| RJ01 | Rejection of invention patent application after publication |