High-strength hard rock hammering guide hole pile foundation steel casing and construction method thereof

Abstract

The invention relates to a high-strength hard rock hammering guide hole pile foundation steel casing and a construction method thereof. Comprising a steel casing positioning type double-layer guide frame, a finalization operation platform steel casing quick splicing support, a casing bottom pumping fiber solidified soil consolidation system, an inclined rock stratum percussion drill touch hitting artificial covering layer system, a steel casing deformation area hanging type inner supporting frame opposite-top repairing system and a steel casing step-by-step pulling-out technology. The construction efficiency of high-strength hard rock hammering guide hole pile foundation steel casing construction can be improved, construction safety is guaranteed, and engineering quality and safety are guaranteed.

Description

Technical Field

[0001] This invention relates to a high-strength hard rock hammer-driven pre-drilled pile foundation steel casing and its construction method, belonging to the field of highway bridge technology, and is applicable to the construction of pile foundation steel casing under high-strength hard rock conditions. Background Technology

[0002] With the development of my country's social and economic construction, transportation infrastructure is becoming increasingly sophisticated, and the number of bridges, as a key component of transportation infrastructure, is increasing year by year. Pile foundations are an important part of bridge structures, playing a vital supporting role for the entire bridge. Their construction quality directly affects the stability, safety, and service life of the entire bridge. Bridge pile foundations are located at the lowest point, extending deep below the ground surface, and are considered concealed works. Due to numerous unforeseen factors such as geological and hydrological conditions, the construction of underwater pile foundations is highly challenging and prone to quality problems.

[0003] When constructing bored piles in water areas or complex geological environments, it is often necessary to pre-install steel casings of a certain depth to ensure the quality of pile foundation construction. During the construction of steel casings, their verticality and stability are often the key points and difficulties in construction control. When encountering hard rock strata, it is also necessary to solve problems such as improving the efficiency of steel casing construction and rapid sinking of steel casings.

[0004] For the construction of steel casing for pile foundations under high-strength hard rock conditions, there is an urgent need to propose a construction method that can improve construction efficiency while ensuring project quality and safety. Summary of the Invention

[0005] The purpose of this invention is to provide a high-strength steel casing for hammer-drilled pile foundations in hard rock and its construction method, which improves the construction efficiency of steel casing construction for high-strength hard rock hammer-drilled pile foundations, ensures construction safety, and guarantees project quality and safety. To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A construction method for steel casing of high-strength hard rock hammer-driven pre-hole pile foundation includes the following construction steps:

[0007] S1. Install a steel casing positioning double-layer guide frame:

[0008] First, the first layer of steel frame is constructed at the construction site level. After the construction is completed, the supporting steel uprights, reinforcing ribs, second layer of steel frame and steel diagonal braces are installed and connected together by welding. Finally, the steel casing is placed in the double-layer guide frame.

[0009] S2. Install the standardized operating platform steel casing quick-assembly bracket:

[0010] Weld the longitudinal beams and transverse beams of the grid frame together beforehand, install the jacks, and fix the arc-shaped limiters to the front end of the jacks;

[0011] After temporarily fixing the conveying steel casing by adjusting the position of the conveying arc limiter with a jack, the upper and lower sections of the steel casing are spliced ​​and welded together.

[0012] S3. Install the fiber-reinforced soil consolidation system by pumping the bottom of the casing:

[0013] A pumping pipe consisting of a three-hole pumping head and a fiber soil outlet is pre-installed, and then the pumping pipe is sent to the bottom of the inner and outer sides of the steel casing to achieve uniform consolidation of the bottom of the steel casing during construction.

[0014] S4. Install an inclined rock strata impact drill for blind drilling of artificial overburden systems:

[0015] First, a steel cofferdam is constructed and inserted into the inclined rock layer. Then, counterweight water bags and fixed steel plates are installed before blind drilling with an impact drill.

[0016] After the construction is completed, insert the delivery pipe into the bottom of the steel cofferdam;

[0017] S5. Install a top-mounted repair system for the suspended internal support frame in the deformation zone of the steel casing:

[0018] First, insert steel columns into the steel casing. After pre-assembling and installing the telescopic rods and rod bases, weld them symmetrically to the steel columns on the left and right sides, and then align them with the deformation area of ​​the top steel casing.

[0019] After the top is completed, the deformed area is cut and re-welded, and mud is injected through the grouting pipe to fill the karst cave to prevent it from collapsing further.

[0020] S6. Use the steel casing step-by-step extraction technique: Install jacks and steel pads at the construction floor level, and install a capping steel plate on the steel casing for the initial extraction of the steel casing;

[0021] Subsequently, the air jack of the steel casing is pulled out by pre-installing the air pump control box, air pipe, low-pressure control port, high-pressure control port, exhaust port, and reinforcing steel.

[0022] Furthermore, the steel casing positioning double-layer guide frame includes a first layer steel frame and a second layer steel frame set at the construction ground level. The first layer steel frame and the second layer steel frame are connected by welded steel diagonal braces, supporting steel uprights and reinforcing ribs to complete the installation of the positioning guide frame for the steel casing.

[0023] Furthermore, the standardized operating platform steel casing quick-assembly support consists of welded grid-like longitudinal beams and grid-like transverse beams. The grid-like frame is equipped with jacks, arc-shaped limiters, and temporarily fixed steel casings.

[0024] Furthermore, during construction, the pumping fiber-reinforced soil consolidation system at the bottom of the casing involves inserting pumping pipes both inside and outside the steel casing to achieve uniform consolidation on both the inside and outside of the casing.

[0025] Furthermore, in the inclined rock strata percussion drilling blind drilling artificial overburden system, a steel cofferdam is first inserted into the inclined rock strata and fixed by a counterweight system consisting of counterweight water bags and fixed steel plates; during installation, the delivery pipe is inserted into the rock strata after blind drilling.

[0026] Furthermore, the top-mounted repair system of the suspended internal support frame in the deformation zone of the steel casing includes steel columns, telescopic rods and rod bases, and grouting pipes are installed inside the karst cave and the steel casing.

[0027] Furthermore, the step-by-step extraction technology for steel casing includes an initial extraction system and an air-jacking extraction system. The initial extraction system includes jacks, steel pads, and capping steel plates at the construction ground level. The air-jacking extraction system consists of an air pump control box, air pipes, low-pressure control holes, high-pressure control holes, exhaust holes, and reinforcing steel.

[0028] Furthermore, the high-strength hard rock hammer-driven pre-hole pile foundation steel casing is constructed using the aforementioned construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing.

[0029] Furthermore, the two pumping pipes outside the steel casing are arranged symmetrically.

[0030] Furthermore, the telescopic rods are installed step by step from top to bottom.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] 1) The steel casing positioning double-layer guide frame and standardized operation platform quick splicing bracket of the present invention can improve the construction quality of steel casing, ensure the verticality of steel casing, and have a good positioning and guiding effect.

[0033] 2) The pumping fiber-reinforced soil consolidation system and the artificial cover layer system for blind drilling of inclined rock strata of the present invention effectively solve the problem of sinking steel casings into rock strata and avoid grout leakage at the bottom of the casing.

[0034] 3) The steel casing deformation zone suspended internal support frame top repair system of the present invention can prevent the sinkhole from continuing to collapse and reduce the safety hazards of construction.

[0035] 4) The step-by-step extraction technology of the steel casing of the present invention can improve the extraction efficiency of the steel casing, and the extracted steel casing can still be reused, which has significant economic benefits.

[0036] 5) This invention innovates the construction process for steel casing construction of high-strength hard rock hammer-driven pile foundations, proposing a steel casing positioning double-layer guide frame, a standardized operation platform for rapid splicing of steel casing, a fiber-reinforced soil consolidation system pumped to the bottom of the casing, an artificial covering layer system for blind drilling of inclined rock strata, a top-mounted internal support system for the deformation zone of the steel casing, and a step-by-step extraction technology for the steel casing. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a steel casing positioning double-layer guide frame structure;

[0038] Figure 2 This is a schematic diagram of a steel casing positioning double-layer guide frame;

[0039] Figure 3 This is a schematic diagram of the standardized operating platform steel casing quick-assembly support structure;

[0040] Figure 4 This is a schematic diagram of the system structure for the fiber-reinforced soil consolidation pumped from the bottom of the casing.

[0041] Figure 5 This is a schematic diagram of the pump pipe head structure;

[0042] Figure 6 This is a schematic diagram of the system architecture for blind drilling of artificial overburden in inclined rock strata using impact drilling.

[0043] Figure 7 This is a schematic diagram of the top-mounted repair system structure of the suspended internal support frame in the deformation zone of the steel casing;

[0044] Figure 8 This is a schematic diagram of the step-by-step extraction structure of the steel casing.

[0045] Explanation of reference numerals in the attached drawings: 1. First layer steel frame; 2. Second layer steel frame; 3. Steel diagonal brace; 4. Supporting steel upright; 5. Reinforcing rib; 6. Construction ground level; 7. Steel casing; 8. Longitudinal beam of the grid frame; 9. Crossbeam of the grid frame; 10. Jack; 11. Arc-shaped limiter; 12. Pumping pipe; 13. Three-hole pumping pipe head; 14. Fiber soil outlet; 15. Inclined rock strata; 16. Counterweight water bag; 17. Fixed steel plate; 18. Steel cofferdam; 19. Conveying pipe; 20. Steel column; 21. Telescopic rod; 22. Rod base; 23. Grouting pipe; 24. Karst cave; 25. Steel pad; 26. Capping steel plate; 27. Air pump control box; 28. Low-pressure control hole; 29. ​​High-pressure control hole; 30. Exhaust hole; 31. Stiffening steel; 32. Air pipe. Detailed Implementation

[0046] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0047] Those skilled in the art should understand that, in the disclosure of this application, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on this application.

[0048] Example 1

[0049] The construction method for steel casing of high-strength hard rock hammer-driven bored pile foundation includes the following steps:

[0050] S1. Install a steel casing positioning double-layer guide frame:

[0051] First, the first layer of steel frame 1 is constructed at a construction ground height of 6. After the construction is completed, the supporting steel uprights 4, reinforcing ribs 5, the second layer of steel frame 2 and steel diagonal braces 3 are installed and connected together by welding. Finally, the steel casing 7 is placed inside the double-layer guide frame.

[0052] S2. Install the standardized operating platform steel casing quick-assembly bracket:

[0053] The longitudinal beams 8 and the transverse beams 9 of the grid frame are pre-welded together, and the jacks 10 are installed. The arc-shaped limiters 11 are fixed to the front end of the jacks 10. After temporarily fixing the steel casing 7 by adjusting the position of the arc-shaped limiters 11 with the jacks 10, the upper and lower sections of the steel casing 7 are spliced ​​and welded together.

[0054] S3. Install the fiber-reinforced soil consolidation system by pumping the bottom of the casing:

[0055] A pumping pipe 12 consisting of a three-hole pumping head 13 and a fiber soil outlet 14 is pre-installed. The pumping pipe 12 is then sent to the bottom of the inner and outer sides of the steel casing 7 to achieve uniform consolidation of the bottom of the steel casing 7 during construction.

[0056] S4. Install an inclined rock strata impact drill for blind drilling of artificial overburden systems:

[0057] First, construct a steel cofferdam 18 and insert it into the inclined rock layer 15. After installing the counterweight water bag 16 and fixing the steel plate 17, perform blind drilling with an impact drill. After the construction is completed, insert the delivery pipe 19 into the bottom of the steel cofferdam 18.

[0058] S5. Install a top-mounted repair system for the suspended internal support frame in the deformation zone of the steel casing:

[0059] First, insert steel columns 20 into the steel casing 7. After pre-assembling and installing telescopic rods 21 and rod bases 22, weld them symmetrically to the steel columns 20 and then align them with the deformed area of ​​the steel casing 7. After aligning, cut and re-weld the deformed area, and inject mud through the grouting pipe 23 to fill the karst cave 24 to prevent the karst cave 24 from collapsing further.

[0060] S6. Construction using a step-by-step extraction technique with steel casing:

[0061] Install jacks 10 and steel pads 25 on the construction ground level 6, and install capping steel plates 26 on the steel casing 7 to perform initial extraction of the steel casing 7;

[0062] Subsequently, by pre-installing the air pump control box 27, air pipe 32, low-pressure control port 28, high-pressure control port 29, exhaust port 30, and reinforcing steel 31, the steel casing 7 is pulled out by air.

[0063] like Figure 1 , Figure 2 As shown, the steel casing positioning double-layer guide frame includes a first layer steel frame 1 and a second layer steel frame 2 set at a construction ground height 6. The first layer steel frame 1 and the second layer steel frame 2 are connected by welded steel diagonal braces 3, supporting steel uprights 4 and reinforcing ribs 5 to complete the installation of the positioning guide frame for the steel casing 7.

[0064] like Figure 3 As shown, the standardized operating platform steel casing quick-assembly bracket consists of welded grid frame longitudinal beams 8 and grid frame transverse beams 9. The grid frame is equipped with jacks 10, arc-shaped limiters 11, and temporarily fixed steel casings 7.

[0065] like Figure 4 , Figure 5 As shown, the bottom pumping fiber-stabilized soil consolidation system is constructed by inserting pumping pipes 12 inside and outside the steel casing 7 during construction to achieve uniform consolidation inside and outside the casing. The pumping pipe 12 includes a three-hole pumping pipe head 13 located at the bottom of the casing and a fiber soil outlet 14.

[0066] like Figure 6 As shown, in the inclined rock strata percussion drilling blind drilling artificial overburden system, a steel cofferdam 18 is first inserted into the inclined rock strata 15 and fixed by a counterweight system consisting of a counterweight water bag 16 and a fixing steel plate 17. During installation, the delivery pipe 19 is inserted into the blind-drilled rock strata.

[0067] like Figure 7 As shown, the top-mounted repair system of the suspended internal support frame in the deformation zone of the steel casing includes steel columns 20, telescopic rods 21, and rod bases 22. Grouting pipes 23 are installed inside the karst cave 24 and the steel casing 7.

[0068] like Figure 8As shown, the step-by-step extraction technology for steel casing includes an initial extraction system and an air-jacking extraction system. The initial extraction system includes jacks 10 at a construction ground height of 6, steel pads 25, and a capping steel plate 26; the air-jacking extraction system consists of an air pump control box 27, air pipes 32, a low-pressure control port 28, a high-pressure control port 29, an exhaust port 30, and reinforcing steel 31.

[0069] Example 2

[0070] The high-strength hard rock hammer-driven pre-hole pile foundation steel casing was constructed using the construction method of the high-strength hard rock hammer-driven pre-hole pile foundation steel casing in Example 1.

[0071] The parts not described in detail in this application are prior art, and therefore are not described in detail in this application.

[0072] It is understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple, and the term "a" should not be understood as a limitation on the number.

[0073] Although this document uses a significant amount of technical terminology, the possibility of using other terms is not excluded. These terms are used merely to facilitate the description and explanation of the nature of this application; interpreting them as any additional limitation would be contrary to the spirit of this application.

[0074] This application is not limited to the above-described preferred embodiments. Anyone can derive other products in various forms under the guidance of this application. However, regardless of any changes made to their shape or structure, any technical solution that is the same as or similar to that of this application falls within the protection scope of this application.

Claims

1. A construction method for steel casing of high-strength hard rock hammer-driven pre-drilled pile foundations, characterized in that, The construction steps include the following: S1. Install a steel casing positioning double-layer guide frame: First, the first layer of steel frame (1) is constructed at the construction ground height (6). After the construction is completed, the supporting steel uprights (4), reinforcing ribs (5), the second layer of steel frame (2) and steel diagonal braces (3) are installed and connected together by welding. Finally, the steel casing (7) is placed in the double-layer guide frame. S2. Install the standardized operating platform steel casing quick-assembly bracket: Weld the longitudinal beam (8) and the transverse beam (9) of the grid frame together in advance, install the jack (10), and fix the arc-shaped limiter (11) at the front end of the jack (10); After using the jack (10) to adjust the position of the conveying arc limiter (11) to temporarily fix the conveying steel casing (7), the upper and lower sections of the steel casing (7) are spliced ​​and welded together. S3. Install the fiber-reinforced soil consolidation system by pumping the bottom of the casing: A pumping pipe (12) consisting of a three-hole pumping head (13) and a fiber soil outlet (14) is pre-installed, and then the pumping pipe (12) is sent to the bottom of the inner and outer sides of the steel casing (7) to achieve uniform consolidation of the bottom of the steel casing (7) during construction. S4. Install an inclined rock strata impact drill for blind drilling of artificial overburden systems: First, a steel cofferdam (18) is constructed. The steel cofferdam (18) is inserted into the inclined rock layer (15). Then, a counterweight water bag (16) and a fixed steel plate (17) are installed before blind drilling with an impact drill. After the construction is completed, insert the delivery pipe (19) into the bottom of the steel cofferdam (18); S5. Install a top-mounted repair system for the suspended internal support frame in the deformation zone of the steel casing: First, insert the steel column (20) into the steel casing (7). After the telescopic rod (21) and the rod base (22) are assembled and installed in advance, they are symmetrically welded to the steel column (20) and then to the deformation area of ​​the top steel casing (7). After the top is completed, the deformed area is cut and re-welded, and mud is injected through the grouting pipe (23) to fill the karst cave (24) to prevent the karst cave (24) from collapsing further; S6. Construction using a step-by-step extraction technique with steel casing: Install jacks (10) and steel pads (25) at the construction ground height (6), and install a capping steel plate (26) on the steel casing (7) to perform the initial extraction of the steel casing (7); Subsequently, the steel casing (7) is pried out by pre-installing the air pump control box (27), air pipe (32), low pressure control hole (28), high pressure control hole (29), exhaust hole (30) and stiffening steel (31).

2. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, The steel casing positioning double-layer guide frame includes a first layer steel frame (1) and a second layer steel frame (2) set at the construction ground height (6). The first layer steel frame (1) and the second layer steel frame (2) are connected by welded steel diagonal braces (3), supporting steel uprights (4) and reinforcing ribs (5) to complete the installation of the positioning guide frame for the steel casing (7).

3. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, The standardized operating platform steel casing quick splicing bracket is composed of welded grid frame longitudinal beams (8) and grid frame cross beams (9). The grid frame is equipped with jacks (10), arc-shaped limiters (11), and temporarily fixed steel casings (7).

4. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, During construction, the pumping fiber-stabilized soil consolidation system at the bottom of the casing is constructed by inserting pumping pipes (12) inside and outside the steel casing (7) to achieve uniform consolidation inside and outside the casing.

5. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, The inclined rock strata impact drilling blind drilling artificial overburden system first inserts a steel cofferdam (18) into the inclined rock strata (15) and fixes it by a counterweight system consisting of a counterweight water bag (16) and a fixed steel plate (17); during installation, the delivery pipe (19) is inserted into the rock strata after blind drilling.

6. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, The steel casing deformation zone suspended internal support top repair system includes steel columns (20), telescopic rods (21) and rod bases (22), and grouting pipes (23) are installed in the karst cave (24) and the steel casing (7).

7. The construction method for high-strength hard rock hammer-driven pre-hole pile foundation steel casing according to claim 1, characterized in that, The step-by-step extraction technology of the steel casing includes an initial extraction system and an air-jacking extraction system. The initial extraction system includes a jack (10) at the construction ground height (6), a steel pad (25), and a capping steel plate (26). The air-jacking extraction system consists of an air pump control box (27), an air pipe (32), a low-pressure control hole (28), a high-pressure control hole (29), an exhaust hole (30), and a reinforcing steel (31).

8. A high-strength steel casing for hammer-driven bored pile foundations in hard rock, characterized in that, The steel casing for high-strength hard rock hammer-driven pile foundations is constructed using the construction method described in any one of claims 1-7.

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