CN111733802A - Construction method of cast-in-place pile penetrating through karst cave - Google Patents
Construction method of cast-in-place pile penetrating through karst cave Download PDFInfo
- Publication number
- CN111733802A CN111733802A CN202010630905.2A CN202010630905A CN111733802A CN 111733802 A CN111733802 A CN 111733802A CN 202010630905 A CN202010630905 A CN 202010630905A CN 111733802 A CN111733802 A CN 111733802A
- Authority
- CN
- China
- Prior art keywords
- pile
- casing
- hole
- pile casing
- enlarged hole
- 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
Images
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
- E02D5/38—Concrete or concrete-like piles cast in position ; Apparatus for making same making by use of mould-pipes or other moulds
-
- 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
- E02D5/665—Mould-pipes or other moulds for making piles
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)
Abstract
The invention discloses a construction method of a cast-in-place pile penetrating through a karst cave, which is characterized by comprising the following steps of: drilling an enlarged hole, drilling an enlarged hole slightly larger than the designed pile diameter on the ground, and penetrating through a karst cave area until the designed pile depth; lowering the pile casing into the enlarged hole, wherein the bottom of the pile casing reaches the designed pile depth, and the inner diameter of the pile casing is slightly larger than the designed pile diameter and slightly smaller than the aperture of the enlarged hole; stabilizing the pile casing, and filling the gap between the pile casing and the enlarged hole with crushed materials until the crushed materials are higher than the ground surface; cleaning a hole and sealing a bottom, cleaning residues in the pile casing, and pouring the bottom seal after the design requirements are met; cleaning a hole and sealing a bottom, cleaning residues in the pile casing, and pouring the bottom seal after the design requirements are met; and (4) pouring a pile foundation, placing a reinforcement cage in the pile casing, and pouring pile body concrete. According to the invention, the enlarged hole is drilled on the ground, the pile casing is placed downwards, the hole is cleaned in the pile casing, and the bottom sealing is poured, so that the hole forming rate can be ensured, and the phenomena of cast concrete loss, pile body cavity and the like are avoided.
Description
Technical Field
The invention relates to the technical field of civil engineering, in particular to a construction method of a cast-in-place pile penetrating through a karst cave.
Background
The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.
The karst landform of China is widely distributed, and the total area reaches 200 kilo square kilometers according to incomplete statistics. The karst area carbonate rock forms a karst cave under the long-term corrosion action of underground water. When the slurry retaining wall is adopted to dig the bored pile in a rotary mode, slurry leakage occurs when a karst cave exists in a stratum, so that an upper soil layer is not supported, the phenomenon of serious hole wall collapse or even the condition of incapability of forming a hole can occur, and the phenomena of concrete loss, pile body necking, pile body cavity, pile breakage and the like can also occur when the pile with the formed hole is poured with concrete in accidental situations. The above conditions show that when karst regions encounter karst caves, the slurry retaining wall is dug into the bored pile in a rotary mode, normal construction cannot be carried out, the quality cannot be guaranteed, and meanwhile, resource waste is serious. The processing of the karst cave and the foundation construction at the karst cave are the important points of various construction project foundation projects, the construction cost and the construction quality are directly influenced, and the key to the successful project construction is the adoption of the measures with economy, reasonability and reliable technology.
Disclosure of Invention
Aiming at the problems, the invention provides a construction method of a cast-in-place pile penetrating through a karst cave.
The invention discloses a construction method of a cast-in-place pile penetrating through a karst cave, which comprises the following steps:
drilling an enlarged hole, drilling an enlarged hole slightly larger than the designed pile diameter on the ground, and penetrating through a karst cave area until the designed pile depth;
lowering the pile casing into the enlarged hole, wherein the bottom of the pile casing reaches the designed pile depth, and the inner diameter of the pile casing is slightly larger than the designed pile diameter and slightly smaller than the aperture of the enlarged hole;
stabilizing the pile casing, and filling the gap between the pile casing and the enlarged hole with crushed materials until the crushed materials are higher than the ground surface;
cleaning a hole and sealing a bottom, cleaning residues in the pile casing, and pouring the bottom seal after the design requirements are met;
and (4) pouring a pile foundation, placing a reinforcement cage in the pile casing, and pouring pile body concrete.
Furthermore, dry operation is adopted during drilling of the enlarged hole, and no slurry is used for supporting.
Further, before drilling the enlarged hole, the following preparation is made:
leveling the site, namely, after determining that the site condition is matched with the geological survey data, leveling and compacting the pile foundation site by using bulldozer equipment;
measuring and positioning, namely measuring the center point of a pile releasing position by using a measuring tool total station or a theodolite according to a design drawing, and leading out positioning piles from the center point to the periphery;
the drilling machine is in place, the central point of the pile position is redetermined by the positioning pile by adopting a cross method, and the central point is checked with the central point of the drill bit of the rotary excavating machine.
And further, when the enlarged hole is drilled, the drill bit adopts a type of drill bit with a diameter larger than the designed pile diameter to perform drilling operation without mud support until the designed pile depth.
Furthermore, the mode of lowering the protection cylinder is mainly based on static insertion and pressing, the lowering process is monitored and checked synchronously, and the protection cylinder is lowered in a vibration mode when lowering difficulty occurs.
And further, after the protective barrel is stabilized, a rotary drilling rig is adopted to clean residues in the protective barrel until the residues meet the design and specification requirements, a back cover is poured at the bottom of the protective barrel, then floating slurry on the surface of the back cover is removed, and then the hole is manually cleaned and the reinforcement cage is placed.
Furthermore, the protective cylinder is made of steel, and the crushed materials used for stabilizing the protective cylinder are drilling slag or soil.
Furthermore, the inner diameter of the pile casing is 150-250 mm larger than the designed pile diameter and 50-150 mm smaller than the diameter of the enlarged hole; the pouring height of the inner back cover of the pile casing is 800-1200 mm, and the cleaning height of the back cover floating slurry accounts for 30% -60% of the total height of the back cover.
By comprehensively adopting the technical scheme, the invention can obtain the following beneficial effects:
the problem that slurry loss, hole collapse, necking down, concrete loss and other phenomena of the retaining wall slurry rotary-excavated pore-forming bored concrete pile in karst landform areas can be effectively solved, construction progress is accelerated, construction quality is guaranteed, serious resource waste is avoided, and the construction requirement of green environmental protection is met.
Drawings
The invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic sectional view of a construction site of a cast-in-place pile according to an embodiment;
fig. 2 is a partially enlarged view of a portion a in fig. 1.
Description of reference numerals:
1-miscellaneous fill layer, 2-clay layer, 3-strongly weathered rock layer, 4-karst cave, 5-rock layer crack, 6-bottom sealing concrete top end, 7-floating slurry bottom end, 8-medium weathered rock layer, 9-drilling slag, 10-steel casing, 11-bottom sealing and 12-enlarged hole.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention.
In the description of the present invention, it is to be understood that the terms indicating an orientation or positional relationship are based on the orientation or positional relationship shown in the drawings only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the drawings of the present invention, it should be understood that different technical features which are not mutually substituted are shown in the same drawing only for the convenience of simplifying the drawing description and reducing the number of drawings, and the embodiment described with reference to the drawings does not indicate or imply that all the technical features in the drawings are included, and thus the present invention is not to be construed as being limited thereto.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
The invention discloses a construction method of a cast-in-place pile penetrating through a karst cave, which comprises the following steps:
Firstly, after confirming that the field condition is consistent with the geological survey data, flattening and compacting the pile foundation field by using bulldozer equipment;
Measuring the center point of a pile releasing position by using a measuring tool total station or a theodolite according to a design drawing, and leading out positioning piles from the center point to the periphery;
step 3, positioning the drilling machine
The positioning pile adopts a cross method to determine the center point of the pile position again and checks the center point with the drill bit of the rotary excavating machine;
Drilling an enlarged hole 12 slightly larger than the designed pile diameter on the ground, wherein the drill bit adopts a type of drill bit larger than the designed pile diameter, and performing drilling operation without mud support to penetrate through a karst cave area until the designed pile depth is reached;
drilling by adopting a drill bit with a diameter larger than the designed pile diameter to form an expanded pile hole, namely an expanded hole 12, so that the pile casing can be smoothly put down to the designed position in the step 5;
the slurry-free supporting hole forming mode is adopted, so that the loss caused by slurry leakage can be effectively avoided;
step 5, lowering down the protective sleeve
A vibration hammer is adopted to lower the protection cylinder into the enlarged hole 12, the mode of lowering the protection cylinder is mainly static insertion, and the monitoring and synchronous checking are carried out simultaneously in the lowering process; the protective sleeve is placed downwards in a static force insertion and pressing mode, so that the hole wall can be prevented from being disturbed, and the collapse of the hole wall caused by vibration in the process of placing is prevented;
when the downward movement is difficult, the vibration mode of the vibration hammer is started to downward move the pile casing, and the bottom of the pile casing directly reaches the designed pile depth; the protective sleeve is lowered in a vibration mode, so that the resistance of lowering the protective sleeve can be reduced, and the protective sleeve can be conveniently lowered to a designed position;
the inner diameter of the pile casing is 150-250 mm larger than the designed pile diameter and 50-150 mm smaller than the aperture of the enlarged hole 12;
the pile casing can be a steel pile casing or a concrete pile casing;
Filling the gap between the protective cylinder and the enlarged hole 12 with crushed aggregates until the crushed aggregates are higher than the ground surface;
the space between the outer side of the pile casing and the wall of the enlarged hole 12 is densely backfilled, so that the pile casing can be stabilized, and the conditions that the pile casing deviates and the verticality does not reach the standard due to mechanical collision during subsequent construction operation, particularly hole cleaning, are ensured;
the crushed aggregates used for stabilizing the casing can be drilling slag 9 or loose materials such as soil and the like, have certain fluidity and stacking strength, can be stacked along the outer wall of the casing when encountering a karst cave, and can plug the interface between the pile and the karst cave by less materials;
Replacing the pile casing with a drill bit meeting the requirement of the designed pile diameter, performing hole cleaning operation in the pile casing, and pouring a back cover 11 at the bottom of the pile casing after the hole cleaning meets the design and specification requirements;
Putting a steel reinforcement cage in the pile casing, and pouring pile body concrete, specifically comprising the following steps,
step 8.1, pouring a back cover 11 at the bottom of the pile casing, wherein the pouring height is 800-1200 mm, as shown in figure 1;
the application of the pile casing and the arrangement of the back cover 11 of the pile casing can effectively solve the problems of hole collapse, hole shrinkage, pile breakage, hole bottom grout flushing, concrete loss and the like, and can smoothly complete the construction of the rotary-excavated hole-filling pile at the karst cave;
the purpose of the bottom sealing 11 is to seal the bottom of the pile casing, prevent the inside and the outside of the pile casing from being communicated at the hole bottom, prevent underground water from permeating into the pile casing to cause hole bottom concrete grout flushing, prevent concrete grout from losing and further reduce pile strength due to the fact that the pressure generated by the concrete in the pile casing is greater than the pressure of underground water outside the pile casing when concrete is poured, and prevent a large amount of concrete grout from losing due to the fact that a karst cave is communicated with underground cracks around the karst cave;
step 8.2, removing the floating slurry on the surface of the back cover 11, wherein the cleaning height accounts for 30-60% of the total height of the back cover 11;
and 8.3, cleaning holes, and then putting down a reinforcement cage.
At least one exemplary embodiment is now provided in connection with the drawings, a detailed description of which is provided in the drawings not intended to limit the scope of the claimed invention, but is merely representative of exemplary embodiments provided in the invention.
The exemplary embodiment specifically relates to a construction method of a cast-in-place pile for penetrating through a karst cave, which comprises the following construction processes:
analyzing and counting whether karst caves exist in the stratum traversed during pile construction and the size, the position and other conditions of the karst caves according to a histogram in a report of pile foundation construction investigation of an engineering project; as shown in fig. 1, the stratum penetrated by the designed pile comprises a mixed filling layer 1, a clay layer 2, a strong weathered rock layer 3 and a medium weathered rock layer 8 from top to bottom, and a karst cave 4 and a stratum fracture 5 exist in the stratum;
measuring the center point of a pile releasing position by using a measuring tool total station or a theodolite according to a design drawing, and leading out positioning piles from the center point to the periphery;
the positioning pile adopts a cross method to determine the center point of the pile position again and checks the center point with the drill bit of the rotary excavating machine;
installing a drill bit which is one type larger than the designed pile diameter on the rotary excavating machine, and performing drilling operation without mud support on the ground to penetrate through a karst cave area until the designed pile depth; the drilled holes are called enlarged holes 12, and the hole diameter of the enlarged holes 12 is 300mm larger than the designed pile diameter;
a vibration hammer is adopted to lower the steel casing 10 into the enlarged hole 12, the lowering mode of the steel casing 10 is a static pressure insertion mode, and the steel casing 10 is monitored and checked synchronously during the lowering process; the inner diameter of the steel casing 10 is 200mm larger than the designed pile diameter, and the length of the steel casing 10 is as deep as the designed pile;
filling and compacting a gap between the outer side of the steel casing 10 and the wall of the enlarged hole 12 by using the drilling slag 9 until the drilling slag 9 is higher than the ground surface so as to stabilize the steel casing 10;
replacing a drill bit of the rotary drilling machine with a drill bit meeting the designed pile diameter, performing hole cleaning operation in the steel casing 10, and pouring a back cover 11 at the bottom of the steel casing 10 after the hole cleaning meets the design and specification requirements;
pouring a back cover 11 at the bottom of the steel casing 10 by using concrete with the same label as the designed pile, wherein the position of the top end 6 of the back cover concrete is shown in figures 1-2; pouring the height of 1000mm by taking the bottom of the steel casing 10 as a reference;
manually chiseling floating slurry on the surface of the bottom-sealed concrete, wherein the position of the bottom end 7 of the floating slurry is shown in figures 1-2; taking the top end 6 of the bottom sealing concrete as a reference, and the cleaning depth is 500 mm;
and (5) cleaning holes, and then putting down a reinforcement cage for dry operation to pour pile body concrete.
The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.
Claims (8)
1. A construction method of a cast-in-place pile penetrating through a karst cave is characterized by comprising the following steps:
drilling an enlarged hole, drilling an enlarged hole slightly larger than the designed pile diameter on the ground, and penetrating through a karst cave area until the designed pile depth;
lowering the pile casing into the enlarged hole, wherein the bottom of the pile casing reaches the designed pile depth, and the inner diameter of the pile casing is slightly larger than the designed pile diameter and slightly smaller than the aperture of the enlarged hole;
stabilizing the pile casing, and filling the gap between the pile casing and the enlarged hole with crushed materials until the crushed materials are higher than the ground surface;
cleaning a hole and sealing a bottom, cleaning residues in the pile casing, and pouring the bottom seal after the design requirements are met;
and (4) pouring a pile foundation, placing a reinforcement cage in the pile casing, and pouring pile body concrete.
2. The construction method according to claim 1, characterized in that: the expanded hole is drilled by dry operation without mud support.
3. The construction method according to claim 1 or 2, characterized in that: before drilling the enlarged hole, the following preparation is carried out:
leveling the site, namely, after determining that the site condition is matched with the geological survey data, leveling and compacting the pile foundation site by using bulldozer equipment;
measuring and positioning, namely measuring the center point of a pile releasing position by using a measuring tool total station or a theodolite according to a design drawing, and leading out positioning piles from the center point to the periphery;
the drilling machine is in place, the central point of the pile position is redetermined by the positioning pile by adopting a cross method, and the central point is checked with the central point of the drill bit of the rotary excavating machine.
4. The construction method according to claim 1 or 2, characterized in that: when the enlarged hole is drilled, the drill bit is the type of the drill bit with the diameter larger than the designed pile diameter, and the drilling operation without mud support is carried out until the designed pile depth.
5. The construction method according to claim 1 or 2, characterized in that: the mode of transferring the protective cylinder is mainly static insertion pressure, the transfer process is monitored and checked synchronously, and the protective cylinder is transferred in a vibration mode when the transfer is difficult.
6. The construction method according to claim 1 or 2, characterized in that: and after the protective barrel is stabilized, cleaning residues in the protective barrel by adopting a rotary drilling rig until the residues meet the design and specification requirements, pouring a back cover at the bottom of the protective barrel, removing floating slurry on the surface of the back cover, and manually cleaning holes and lowering a reinforcement cage.
7. The construction method according to claim 1 or 2, characterized in that: the protective cylinder is made of steel, and the crushed materials used for stabilizing the protective cylinder are drilling slag or soil.
8. The construction method according to claim 1 or 2, characterized in that: the inner diameter of the pile casing is 150-250 mm larger than the designed pile diameter and 50-150 mm smaller than the aperture of the enlarged hole; the pouring height of the inner back cover of the pile casing is 800-1200 mm, and the cleaning height of the back cover floating slurry accounts for 30% -60% of the total height of the back cover.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010630905.2A CN111733802A (en) | 2020-07-03 | 2020-07-03 | Construction method of cast-in-place pile penetrating through karst cave |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010630905.2A CN111733802A (en) | 2020-07-03 | 2020-07-03 | Construction method of cast-in-place pile penetrating through karst cave |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111733802A true CN111733802A (en) | 2020-10-02 |
Family
ID=72654047
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010630905.2A Pending CN111733802A (en) | 2020-07-03 | 2020-07-03 | Construction method of cast-in-place pile penetrating through karst cave |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111733802A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115450204A (en) * | 2022-10-17 | 2022-12-09 | 上海宝冶集团有限公司 | Construction method for hole forming of karst cave geological concrete by recharging and matching with rotary digging of steel pile casing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204401612U (en) * | 2015-01-21 | 2015-06-17 | 成都市第四建筑工程公司 | A kind of super-large diameter all steel casing does operation pore-creating filling pile construction equipment |
| CN205046551U (en) * | 2015-09-29 | 2016-02-24 | 昆明捷程桩工有限责任公司 | Solution cavity district sleeve pipe bored concrete pile |
| CN105386408A (en) * | 2015-11-02 | 2016-03-09 | 中交第二航务工程局有限公司 | Deep-water bridge pile foundation construction method |
| CN206859211U (en) * | 2017-06-08 | 2018-01-09 | 中交第二航务工程勘察设计院有限公司 | A kind of elastic steel cylinder of drilled pile solution cavity leak stopping |
| CN109629563A (en) * | 2019-01-10 | 2019-04-16 | 湖北工业大学 | A kind of pile foundation goes along with sb. to guard him construction method |
-
2020
- 2020-07-03 CN CN202010630905.2A patent/CN111733802A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN204401612U (en) * | 2015-01-21 | 2015-06-17 | 成都市第四建筑工程公司 | A kind of super-large diameter all steel casing does operation pore-creating filling pile construction equipment |
| CN205046551U (en) * | 2015-09-29 | 2016-02-24 | 昆明捷程桩工有限责任公司 | Solution cavity district sleeve pipe bored concrete pile |
| CN105386408A (en) * | 2015-11-02 | 2016-03-09 | 中交第二航务工程局有限公司 | Deep-water bridge pile foundation construction method |
| CN206859211U (en) * | 2017-06-08 | 2018-01-09 | 中交第二航务工程勘察设计院有限公司 | A kind of elastic steel cylinder of drilled pile solution cavity leak stopping |
| CN109629563A (en) * | 2019-01-10 | 2019-04-16 | 湖北工业大学 | A kind of pile foundation goes along with sb. to guard him construction method |
Non-Patent Citations (1)
| Title |
|---|
| 刘君城: "浅议桩基施工遇地下废弃防空洞的处理办法", 《江西化工》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115450204A (en) * | 2022-10-17 | 2022-12-09 | 上海宝冶集团有限公司 | Construction method for hole forming of karst cave geological concrete by recharging and matching with rotary digging of steel pile casing |
| CN115450204B (en) * | 2022-10-17 | 2023-11-21 | 上海宝冶集团有限公司 | Construction method for rotary digging and pore forming of karst cave geological concrete recharging matched with steel casing |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106400782B (en) | A kind of construction method for going along with sb. to guard him hole-drilling interlocking pile using rotary drilling rig construction foundation pit | |
| KR101071958B1 (en) | underground excuvation pile construction method using percussion rotary drill | |
| CN111236216A (en) | Construction method of bridge drilled pile | |
| CN110761265A (en) | Karst cave disposal method for deep foundation pit pile foundation construction in karst area | |
| CN113668527A (en) | Construction method for inserting long steel pile casing under rotary digging pile construction of deep rockfill silt stratum | |
| CN105649010A (en) | Grouting pile construction technology | |
| CN104652427A (en) | Construction method of drilling pile | |
| CN111733802A (en) | Construction method of cast-in-place pile penetrating through karst cave | |
| CN110306536A (en) | A kind of mud off pore-creating filling pile construction technology | |
| CN114059527A (en) | Large-diameter mixing pile construction method suitable for high-groundwater-level hard soil layer | |
| CN113216142A (en) | Grouting treatment method and system for underwater karst cave in karst development area | |
| CN113668564A (en) | Construction method for supporting and reinforcing open-cut underground passage adjacent to subway station | |
| CN202925575U (en) | Pre-buried structure for core-drilling detection of foundation pile | |
| CN112878315A (en) | End-bearing rotary-digging hole-forming cast-in-place pile based on Civil 3D technology and construction method | |
| CN111962507A (en) | Pile foundation hole forming method | |
| CN110067205A (en) | A kind of permanent protecting tube embedding construction method of bridge pier column outsourcing | |
| CN211735404U (en) | Anti-over-irrigation system for long spiral bored pile | |
| CN211113598U (en) | Karst cave handling system for deep foundation pit pile foundation construction in karst area | |
| CN113481971A (en) | Construction method for forming hole of cast-in-place pile under complex geological condition | |
| KR101962341B1 (en) | Construction method of cast-in-place concrete pile with semi-spherical end | |
| CN110820733A (en) | Improved mechanical rapid hole forming construction method for simple rectangular slide-resistant pile | |
| CN113718798B (en) | Construction method for layered construction pore-forming of rock-socketed secant pile in riprap region near sea | |
| CN114197453B (en) | Bored pile adopting prefabricated high-strength concrete pile head | |
| CN112431195B (en) | Pile planting and grouting construction method for tubular piles | |
| CN114622559B (en) | Construction method for controlling perpendicularity of ultra-large diameter rock-socketed rotary digging pile |
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: 20201002 |
|
| RJ01 | Rejection of invention patent application after publication |