A construction method for reinforced piles

Abstract

The invention discloses a construction method of a force-expanded pile, relates to the field of building pile bottom, and aims to improve the pile body quality of the force-expanded pile. The key points of the technical solution are: S1, a pile driver with a blade steel casing equipped with a rotating device and a shotcreting system is moved to the pile position, a tamping column hammer is arranged in the steel casing, and the rotating device is turned on when sinking the pipe to the designed elevation, and the column hammer is used to tamp the soil body, and the steel casing is sunk to the designed elevation synchronously or alternately; S2, the expansion base material is put into the entrance of the steel casing, and the expansion base material is compacted with the column hammer; S3, after the bearing capacity required by the design is reached, the column hammer is raised, and the core pile is placed or cast; S4, the shotcreting system is turned on, the steel casing with a blade is rotated, the slurry is sprayed out from the bottom of the pile and stirred and lifted, and the steel casing is raised after the stirring is completed; S5, after the bottom of the steel casing reaches the pile top elevation, the powder spraying or shotcreting is stopped, and the steel casing is continuously raised until it is raised to the ground to form a pile. The construction method of a force-expanded pile of the invention can prepare a pile with high bearing capacity.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and more specifically, to a construction method of a reinforced expanded pile. Background Art

[0002] In multi-story or high-rise buildings in soft soil areas, prestressed concrete pipe piles and bored cast-in-place piles are the most commonly used foundation forms. However, both prestressed concrete pipe piles and bored cast-in-place piles are friction piles, and the bearing capacity of their pile bodies needs to be improved.

[0003] At present, a kind of rigid composite pile has appeared on the market, which is generally composed of cement soil mixing pile and pipe pile. The cement soil mixing pile uses a large mixing rod to spray cement slurry from its nozzle into the foundation at high pressure, and forcibly mixes it with the original soil to form a large diameter cement soil mixing pile. Before the cement soil mixing pile begins to set, the pipe pile is inserted into it to form a new type of composite load-bearing pile.

[0004] However, the current construction of rigid composite piles requires multiple devices to perform construction in turns or simultaneously. This affects the construction period and cannot achieve complete concentricity and coaxiality, which affects the molding quality of the piles.

[0005] Therefore, a new solution needs to be proposed to solve this problem. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention aims to provide a construction method for reinforced expanded piles, by simultaneously expanding the bottom during piling and spraying and mixing during lifting, so that the outer mixing piles and the core piles are formed synchronously.

[0007] The above technical purpose of the present invention is achieved through the following technical solutions: A construction method of a reinforced pile, comprising the following steps:

[0008] S1. Move the pile driver with blade steel casing equipped with a rotating device and a shotcrete system to the pile position. A tamping column hammer is installed in the steel casing. When sinking the pipe, turn on the rotating device to sink it to the designed elevation. At the same time, use the column hammer to tamp the soil, and sink it to the designed elevation synchronously or alternately.

[0009] S2. Add the expansion material in batches from the entrance of the steel casing for multiple times, compact the expansion material with a column hammer, lift the column hammer to a certain height, and determine the end bearing capacity by measuring the cumulative penetration of 3 to 10 hits;

[0010] S3. After the bearing capacity required by the design is reached, the column hammer is raised and the core pile is placed or cast;

[0011] S4, start the spraying system, rotate the steel casing with blades, spray the slurry from the bottom of the pile and stir and lift it up, stir it up and down several times as required and spray powder or slurry at the same time, and lift the steel casing after stirring;

[0012] S5. After the bottom of the steel casing reaches the pile top elevation, stop spraying powder or grouting, and continue to lift the steel casing until it is out of the ground, thus forming a pile.

[0013] The present invention is further configured as follows: the blades of the steel casing are spirally arranged on the outer peripheral wall of the steel casing.

[0014] The present invention is further configured as follows: the steel casing is connected to at least one motor, and the steel casing is driven to rotate by the motor when the pipe is sunk or pulled out.

[0015] The present invention is further configured as follows: the steel casing is a single-layer casing or a double-layer casing.

[0016] The present invention is further configured as follows: when the steel casing is a double-layer casing, the spraying system is arranged in the gap between the double-layer casing.

[0017] The present invention is further configured as follows: the double-layer casing comprises an outer cylinder and an inner cylinder, a bearing is installed between the inner cylinder and the outer cylinder, the inner cylinder and the outer cylinder are rotatably connected, an inner ring gear is fixed on the top of the outer cylinder, two groups of motors are fixed on the inner cylinder, and the motor shaft ends of the two groups of motors are respectively fixed with driving gears meshing with the inner ring gear; the spraying system comprises a spraying pipe, and two groups of stirring structures are arranged at the bottom of the outer cylinder, and the stirring structure comprises an auxiliary blade, an overhanging block, a fixing seat, a spring latch and an unlocking drive pin; the overhanging block is fixed on the auxiliary blade, and the fixing seat is fixed It is fixed at the end of the outer cylinder, and the protruding block and the auxiliary blade are fixed by a spring pin arranged at the fixing seat, and the unlocking drive pin is fixed on the outside of the end of the shotcrete pipe; when the shotcrete pipe is not grouting, the auxiliary blade is horizontally clamped at the bottom of the outer cylinder by a spring pin installed at the bottom of the outer cylinder; when the shotcrete pipe is grouting, the pipeline at the bottom of the shotcrete pipe expands and the unlocking drive pin is used to unlock the auxiliary blade clamped at the bottom of the outer cylinder, and the auxiliary blade flips at a certain angle under its own gravity and pulls open the cover at the end of the shotcrete pipe for grouting, and the auxiliary blade is used to stir and degas the grouting slurry.

[0018] The present invention is further configured as follows: when the steel casing is a single-layer casing, the spraying system is arranged on the outer wall of the single-layer casing.

[0019] The present invention is further configured as follows: the steel casing is also equipped with a vibration device.

[0020] The present invention is further configured as follows: the blade is a single-layer blade or a multi-layer spiral blade.

[0021] The present invention is further configured as follows: the pile driver is an integrated machine, integrating external pile construction, internal pile construction, body expansion construction, and powder spraying and grouting construction. The walking mode can be pipe-walking type, walking type, crawler type, hydraulic type, etc. The pipe sinking method includes rotary drilling pipe sinking, vibration pipe sinking, counter-pressure pipe sinking, or a combination of the three.

[0022] The present invention is further configured as follows: the base expansion material is one or more of dry cement mortar, dry concrete, concrete, crushed stone, crushed brick or steel slag.

[0023] The present invention is further configured as follows: the core pile is cast-in-place reinforced concrete, cast-in-place plain concrete, prefabricated pipe pile, prefabricated solid square pile, prefabricated hollow square pile or prefabricated special-shaped pile.

[0024] The present invention is further configured as follows: the powder spraying material can be various types of cementitious materials such as cement, cement paste, cement mortar or concrete, and can be dry sprayed or wet sprayed according to the geological conditions.

[0025] In summary, the present invention has the following beneficial effects:

[0026] 1. The present invention expands the bottom and forms piles at the same time as the core pile is constructed, thus solving the problem that multiple devices are required to construct the piles at the same time. The present invention only needs one device, which has the functions of hole forming (with or without soil taking), bottom expansion and compaction, powder spraying and grouting, etc., which greatly reduces the construction cost and improves the work efficiency;

[0027] 2. The present invention solves the problem that the bottom expansion effect of the force-expanded pile is not obvious and the bearing capacity is low by using a column hammer to expand the bottom in the steel casing;

[0028] 3. The present invention can arbitrarily select the core pile forming method, which solves the problem of single core pile of rigid expansion pile. The present invention can diversify the core pile selection to meet the requirements of various projects;

[0029] 4. The present invention solves the pile body quality problems of the reinforced concrete piles using cast-in-place reinforced concrete as the core piles, such as grout leakage, grout leakage, reinforcement leakage, neck shrinkage, etc. after the piles are completed;

[0030] 5. The present invention solves the problem that the core pile of the rigid expansion pile and the outer pile are not concentric or coaxial. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the construction steps of the present invention;

[0032] Figure 2 It is one of the structural schematic diagrams of the double-layer casing;

[0033] Figure 3 This is one of the structural cross-sectional views of the double-layer casing;

[0034] Figure 4 This is the second structural diagram of the double-layer casing;

[0035] Figure 5 for Figure 4 A in the enlarged view;

[0036] Figure 6 This is the third structural diagram of the double-layer casing;

[0037] Figure 7 This is the second structural cross-sectional view of the double-layer casing;

[0038] Figure 8 for Figure 7 Enlarged view of point B in .

[0039] In the figure: 1. electric motor; 2. steel casing; 3. shotcrete pipe; 4. column hammer; 5. blade; 6. bottom expansion material; 7. core pile; 8. outer pile; 21. outer cylinder; 22. inner cylinder; 23. bearing; 24. inner ring gear; 26. driving gear; 27. stirring structure; 271. auxiliary blade; 272. overhanging block; 273. fixing seat; 275. spring latch; 277. unlocking drive pin; 276. cover. DETAILED DESCRIPTION

[0040] The present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0041] refer to Figures 1 to 8 , a construction method of reinforced pile expansion, such as Figure 1 As shown, it includes the following steps:

[0042] S1. Move the pile driver with a rotating device or a vibrating rotating device and a blade 5 steel casing 2 with a powder spraying or grouting system to the pile position. The steel casing 2 with the blade 5 is provided with a tamping column hammer 4. When sinking the pipe, turn on the rotating device or the vibrating rotating device to sink to the designed elevation, or use the column hammer 4 to tamp the soil at the same time, and sink to the designed elevation synchronously or alternately. The pipe sinking method is one of the following or a combination:

[0043] The bottom of the steel casing 2 is sealed, the steel casing 2 is rotated, and the blade 5 is used to cut the soil and sink it to the pile bottom elevation.

[0044] The steel casing 2 is rotated, the soil is cut by the blade 5, and the soil in the pipe is rammed by the column hammer 4, and the pipe is sunk to the designed elevation simultaneously.

[0045] The soil in the pipe is tamped with a column hammer 4, and the vibration device is turned on to simultaneously sink the pipe to the designed elevation.

[0046] S2. After the pipe is sunk to the pile bottom elevation, the bottom expansion material 6 is added in batches from the feeding port for multiple times, and the bottom expansion material 6 is compacted by the column hammer 4. According to the feeding amount indicated by the mark on the wire rope, the bottom expansion material 6 is added multiple times for compaction until the feeding amount or bearing capacity requirement required by the design is reached. The column hammer 4 is lifted to a certain height, and the end bearing capacity is determined by measuring the cumulative penetration of 3 to 10 hits.

[0047] S3. After the bearing capacity reaches the design requirements, the column hammer 4 is brought out and the core pile 7 is placed or cast: the column hammer 4 is brought out of the casing and the core pile 7 is hoisted by the winch on the pile driver. If the core pile 7 is a reinforced concrete pile or a plain concrete pile, the pile body concrete needs to be cast.

[0048] S4. After the core pile 7 is placed or poured, the powder spraying or grouting port is connected, the powder spraying or grouting system is turned on, and the steel casing 2 with the blade 5 is rotated. The powder spraying or grouting material is sprayed out from the nozzle at the bottom of the pile and stirred and lifted. According to the requirements, multiple up and down stirring is carried out while powder spraying or grouting, and the steel casing 2 is lifted out while stirring. The rotation and lifting speed are adjusted according to the geological conditions.

[0049] S5. After the bottom of the steel casing 2 reaches the pile top elevation, the powder spraying or grouting can be stopped, and the steel casing 2 can be continuously raised until it is raised from the ground, thus forming a pile.

[0050] The rotating device or vibrating rotating device described in the above step S1 has a steel casing 2 with a blade 5 of a powder spraying or spraying system, the diameter of the steel casing 2 is 100mm~5000mm, and the top of the steel casing 2 with the blade 5 is provided with a gear, which is driven by one or more motors 1, and the steel casing 2 with the blade 5 can be driven to rotate when sinking or pulling the pipe. The steel casing 2 can be a single-layer casing or a double-layer casing. There are several powder spraying and spraying pipes 3 in the double-layer casing that are connected to the rotating blade 5 at the bottom of the casing, or powder or spraying can be directly performed from the gap between the double-layer casing. There are several powder spraying and spraying pipes 3 on the outside of the single-layer casing that are connected to the bottom rotating blade 5. The rotating device on the top of the steel casing 2 can be provided with a vibration device, and the vibration device can be turned on to assist in sinking or pulling the pipe for complex terrain.

[0051] The rotating blade 5 can be set at the bottom of the steel casing 2, or can be installed on the outer wall of the steel casing 2 through the entire length or partially. The spraying pipe 3 can be set at any position of the rotating blade 5 or the steel casing 2. The rotating blade 5 can be a single-layer blade 5 or a multi-layer spiral blade 5.

[0052] The hammer 4 that strikes in S1 has a certain mass and rigidity.

[0053] The expansion material described in S2 includes dry hard materials such as dry cement mortar, dry concrete, concrete, crushed stone, broken bricks, steel slag, etc.

[0054] The core pile 7 described in S3 includes various types of prefabricated piles such as cast-in-place reinforced concrete, cast-in-place plain concrete, prefabricated pipe piles, prefabricated solid square piles, prefabricated hollow square piles, and prefabricated special-shaped piles.

[0055] The powder spraying material described in S4 can be various types of cementitious materials such as cement, cement paste, cement mortar or concrete, and can be dry sprayed or wet sprayed according to the geological conditions.

[0056] refer to Figures 2 to 8 , wherein, when the steel casing 2 is a double-layer casing, the double-layer casing includes an outer cylinder 21 and an inner cylinder 22, a bearing 23 is installed between the inner cylinder 22 and the outer cylinder 21, and the inner cylinder 22 and the outer cylinder 21 are rotatably connected, an inner ring gear 24 is fixed on the top of the outer cylinder 21, two groups of motors 1 are fixed on the inner cylinder 22, and the ends of the motor 1 shafts of the two groups of motors 1 are respectively fixed with driving gears 26 meshing with the inner ring gear 24; the spraying system includes a spraying pipe 3, and two groups of stirring structures 27 are arranged at the bottom of the outer cylinder 21, and the stirring structure 27 includes an auxiliary blade 271, an overhanging block 272, a fixing seat 273, a spring latch 275 and an unlocking drive pin 277; the overhanging block 272 is fixed on the auxiliary blade 271, and the fixing seat 273 is fixed on the auxiliary blade 271. The fixed seat 273 is fixed to the end of the outer cylinder 21, and the spring pin 275 arranged at the fixed seat 273 fixes the protruding block 272 and the auxiliary blade 271, and the unlocking drive pin 277 is fixed to the outer side of the end of the spraying pipe 3; when the spraying pipe 3 is not grouting, the auxiliary blade 271 is horizontally clamped to the bottom of the outer cylinder 21 through the spring pin 275 installed at the bottom of the outer cylinder 21; when the spraying pipe 3 is grouting, the pipeline at the bottom of the spraying pipe 3 expands and the unlocking drive pin 277 is used to unlock the auxiliary blade 271 clamped to the bottom of the outer cylinder 21, and the auxiliary blade 271 flips at a certain angle under its own gravity and pulls open the cover 276 at the end of the spraying pipe 3 for grouting, and the auxiliary blade 271 is used to stir and degas the grouting slurry.

[0057] refer to Figures 2 to 8When the steel casing 2 adopts a double-layer casing, two sets of motors 1 can be used to drive the driving gear 26 to rotate during drilling, and then the driving gear 26 is meshed with the inner ring gear 24 to drive the outer cylinder 21 to rotate. The rotation of the outer cylinder 21 can drive the blade 5 outside it to perform the drilling operation; when the drilling is completed and grouting operation is required, the grouting can be performed by the grouting pipe 3 in the grouting system. Before grouting, since the grouting pipe 3 is empty, the fixing seat 273 and the overhanging block 272 will be locked by the spring latch 275, and the auxiliary blade 271 set at the bottom of the outer cylinder 21 will be fixed; when grouting starts, since the bottom of the grouting pipe 3 will be The slurry drives expansion, and the expanded spray pipe 3 will deform, so that the unlocking drive pin 277 pushes the spring pin 275, so that the spring pin 275 releases the lock between the protruding block 272 and the fixed seat 273, so that the auxiliary blade 271 flips downward under the action of its own gravity. The downward flipped auxiliary blade 271 can stir the injected slurry when the outer cylinder 21 rotates, thereby improving the mixing uniformity of the slurry. Since a pull rope is connected between the auxiliary blade 271 and the cover 276 at the end of the spray pipe 3, when the auxiliary blade 271 flips, the cover 276 can be pulled open synchronously to perform grouting operations, thereby realizing linkage and feedback linkage.

[0058] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A construction method for a reinforced expanded pile, characterized in that: The following steps are involved: S1. Move a pile driver equipped with a rotating device and a blade (5) of a shotcrete system and a steel casing (2) to the pile position. A tamping column hammer (4) is provided in the steel casing (2). When sinking the pipe, turn on the rotating device and sink it to the designed elevation. At the same time, use the column hammer (4) to tamp the soil, and sink it to the designed elevation synchronously or alternately. S2, adding the bottom expansion material (6) in batches multiple times from the entrance of the steel casing (2), compacting the bottom expansion material (6) with a column hammer (4), lifting the column hammer (4) to a certain height, and determining the end bearing capacity by measuring the cumulative penetration of 3 to 10 hits; S3. After the bearing capacity required by the design is reached, the column hammer (4) is removed and the core pile (7) is placed or cast; S4, start the spraying system, rotate the steel casing (2) with the blade (5), spray the slurry from the bottom of the pile and stir and lift it, stir it up and down several times as required, and spray powder or slurry at the same time, and take out the steel casing (2) after stirring; S5. After the bottom of the steel casing (2) reaches the pile top elevation, stop spraying powder or grouting, and continue to lift the steel casing (2) until it is lifted out of the ground, thus forming a pile.

2. A construction method for reinforced expanded piles according to claim 1, characterized in that: The blades (5) of the steel casing (2) are spirally arranged on the outer peripheral wall of the steel casing (2).

3. A construction method for reinforced piles according to claim 1 or 2, characterized in that: The steel casing (2) is connected to at least one motor (1), and the steel casing (2) is driven to rotate by the motor (1) when the pipe is sunk or pulled out.

4. The construction method of a reinforced expanded pile according to claim 1, characterized in that: The steel casing (2) is a single-layer casing or a double-layer casing.

5. A construction method for reinforced expanded piles according to claim 4, characterized in that: When the steel casing (2) is a double-layer casing, the spraying system is arranged in the gap between the double-layer casing.

6. A construction method for reinforced expanded piles according to claim 5, characterized in that: The double-layer casing comprises an outer cylinder (21) and an inner cylinder (22); a bearing (23) is installed between the inner cylinder (22) and the outer cylinder (21); the inner cylinder (22) and the outer cylinder (21) are rotatably connected; an inner ring gear (24) is fixed on the top of the outer cylinder (21); two groups of motors (1) are fixed on the inner cylinder (22); the shaft ends of the two groups of motors (1) are respectively fixed with driving gears (26) meshing with the inner ring gear (24); the spraying system comprises a spraying pipe (3); two groups of stirring structures (27) are arranged at the bottom of the outer cylinder (21); the stirring structures (27) comprise auxiliary blades (271), an overhanging block (272), a fixing seat (273), a spring latch (275) and an unlocking drive pin (277); the overhanging block (272) is fixed on the auxiliary blade (271); the fixing seat (273) is a spring latch (275) and an unlocking drive pin (277); The outer tube (21) is fixed to the end of the outer tube (21), and the protruding block (272) and the auxiliary blade (271) are fixed by a spring latch (275) arranged at the fixing seat (273), and the unlocking driving pin (277) is fixed to the outer side of the end of the spraying pipe (3); when the spraying pipe (3) is not grouting, the auxiliary blade (271) is horizontally clamped to the bottom of the outer tube (21) by the spring latch (275) installed at the bottom of the outer tube (21); when the spraying pipe (3) is grouting, the pipeline at the bottom of the spraying pipe (3) expands and the auxiliary blade (271) clamped to the bottom of the outer tube (21) is unlocked by the unlocking driving pin (277), and the auxiliary blade (271) turns over at a certain angle under its own weight and pulls open the cover (276) at the end of the spraying pipe (3) to perform grouting, and the auxiliary blade (271) is used to stir and degas the grouting slurry.

7. The construction method of a reinforced expanded pile according to claim 4, characterized in that: When the steel casing (2) is a single-layer casing, the spraying system is arranged on the outer wall of the single-layer casing; the steel casing (2) is also equipped with a vibration device.

8. The construction method of a reinforced expanded pile according to claim 2, characterized in that: The blade (5) is single-layer or multi-layer.

9. The construction method of a reinforced expanded pile according to claim 1, characterized in that: The pile driver is an integrated machine, integrating external pile (8) construction, internal pile construction, bottom expansion construction, and powder spraying and grouting construction. The walking mode is pipe-walking type, walking type, crawler type or hydraulic type.

10. The construction method of a reinforced expanded pile according to claim 1, characterized in that: The pipe sinking method is a rotating pipe sinking method, a vibrating pipe sinking method, a counter-pressure pipe sinking method or a combination of the three.

11. The construction method of a reinforced expanded pile according to claim 1, characterized in that: The base expansion material (6) is one or more of dry cement mortar, concrete, crushed stone, crushed brick or steel slag; the core pile (7) is cast-in-place reinforced concrete, cast-in-place plain concrete, prefabricated pipe pile, prefabricated solid square pile, prefabricated hollow square pile or prefabricated special-shaped pile.

12. A construction method for reinforced expanded piles according to claim 1, characterized in that: The powder spraying material is cement, cement paste, cement mortar or concrete, and can be dry sprayed or wet sprayed according to geological conditions.

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