Screw anchor counter-force pile pressing method suitable for foundation reinforcement

Abstract

The invention discloses a screw anchor counter-force pile pressing method suitable for foundation reinforcement. The screw anchor counter-force pile pressing method comprises the steps that S1, a plurality of screw anchors are drilled into a soil body within the pile pressing range; s2, grouting reinforcement is conducted on the soil body around the spiral anchor; s3, the top of the spiral anchor is fixedly connected with a pressing pile base; s4, a pile pressing device is installed on the pile pressing base; s5, the first-section reinforcing pile body is clamped through a force transmission hoop, and the jack drives the force transmission hoop to move downwards through an inner push rod so that the first-section reinforcing pile body can be pressed into the soil body step by step; the next section of reinforcing pile body is connected, and the pile pressing operation is repeated until all the reinforcing pile bodies are pressed into the soil body; s6, the pile pressing device and the pile pressing base are sequentially dismantled; s7, the reinforcing piles are sealed; and S8, the spiral anchor is rotationally pulled out in the direction opposite to the direction in which the spiral anchor is drilled into the soil body within the pile pressing range, and holes caused by pulling out the spiral anchor are grouted and blocked. The device has the advantages that the structure is simple, construction is convenient, and counterforce provided by a raft or a bearing platform is not needed.

Description

Technical Field

[0001] The present invention relates to the technical field of building foundation reinforcement, and in particular to a screw anchor reaction force pile pressing method applicable to foundation reinforcement. Background Art

[0002] The pile pressing method for foundation reinforcement utilizes static pressure to press precast piles or steel pipe piles into the soil, and the upper load is jointly borne by the friction force, cohesive force between the pile and the soil mass, and the end resistance of the pile. The core lies in using a reaction device (such as a jack) to press the pile body into a predetermined depth section by section to achieve the purpose of reinforcing the foundation.

[0003] The disadvantages of the traditional pile pressing method for building foundation reinforcement are as follows: (1) The pile pressing device is relatively bulky and the operation is complex; (2) An existing bearing platform or raft foundation is required to provide reaction force; (3) The construction cost is relatively high.

[0004] Therefore, a screw anchor reaction force pile pressing method applicable to foundation reinforcement that can solve the above problems is needed. Summary of the Invention

[0005] The purpose of the present invention is to provide a screw anchor reaction force pile pressing method applicable to foundation reinforcement according to the deficiencies of the above-mentioned prior art. This reaction force pile pressing method utilizes a reaction device and a pile pressing device to press the reinforcement pile into the soil body, achieving rapid pile pressing.

[0006] The purpose of the present invention is achieved by the following technical solutions: A screw anchor reaction force pile pressing method applicable to foundation reinforcement, the reaction force pile pressing method comprising: S1: Driving a plurality of screw anchors into the soil within the pile pressing range; S2: Grouting and reinforcing the soil around the screw anchors to form a grouted body; S3: Erecting a pile pressing base on the grouted body and connecting and fixing the top of the screw anchor to the pile pressing base to form a reaction device; S4: Installing a pile pressing device on the pile pressing base; Wherein, the pile pressing device includes a jack, an inner push rod, and a force transmission clamping hoop. The upper end and the lower end of the inner push rod are respectively connected to the jack and the force transmission clamping hoop, and the force transmission clamping hoop is used for clamping the reinforcement pile body; S5: Using the force transmission clamping hoop to clamp the first section of the reinforcement pile body, and the jack drives the force transmission clamping hoop to move downward through the inner push rod to press the first section of the reinforcement pile body into the soil step by step to complete the pile pressing operation; connecting the next section of the reinforcement pile body and repeating the pile pressing operation until all the reinforcement pile bodies are pressed into the soil to form a reinforcement pile; S6: dismantling the pile pressing device and the pile pressing base in sequence; S7: sealing the reinforcement piles; S8: pulling out the spiral anchor by rotating it in the direction opposite to the direction in which the spiral anchor is drilled into the soil within the pile driving range, and sealing the pores caused by pulling out the spiral anchor by grouting.

[0007] The pile driving device also includes connecting rods, transverse connecting plates and longitudinal connecting plates. There are four connecting rods and the four connecting rods are arranged in a rectangular shape. The top ends of the four connecting rods are connected in the transverse and longitudinal directions respectively by two transverse connecting plates and two longitudinal connecting plates. There are two jacks and the two jacks are respectively installed on the two transverse connecting plates. The lower end of the inner push rod passes through the transverse connecting plate and is connected to the force transmission hoop. The force transmission hoop is respectively mounted on the four connecting rods.

[0008] The pile driving base includes two relatively arranged longitudinal plates and two relatively arranged transverse plates, the two transverse plates are located in the middle of the two longitudinal plates, the reinforced pile body is located in the space formed by the two longitudinal plates and the two transverse plates, the four connecting rods are respectively arranged on the two transverse plates in pairs, and the spiral anchor is connected to the end of the longitudinal plate.

[0009] A plurality of large-diameter spiral steel blades are arranged at the bottom of the spiral anchor.

[0010] In step S1, according to the pile driving load required for foundation reinforcement and the soil conditions, the spiral anchors of different specifications, sizes, lengths and quantities are selected; when the shallow soil properties are good, a combination of small specifications and large quantities of spiral anchors is selected; when the shallow soil properties are poor, a combination of large specifications and small quantities of spiral anchors is selected; when the soil layer is uneven, a combination of large specifications and small specifications of spiral anchors is selected.

[0011] In step S1, a first limiting nut is installed on the top of the spiral anchor.

[0012] In step S3, a second limiting nut is installed on the top of the spiral anchor, and the pile driving base is fixed by the first limiting nut and the second limiting nut.

[0013] In step S5, pressing the reinforced pile body into the soil step by step means that when the reinforced pile body is pressed into the soil to a certain distance, the inner push rod reaches the maximum stroke, the connection between the force transmission hoop and the reinforced pile body is released, the inner push rod retreats to the minimum stroke, the force transmission hoop is reconnected to the reinforced pile body, and the reinforced pile body continues to be pressed into the soil.

[0014] The advantages of the present invention are: (1) Simple structure and convenient construction, without the need for raft or pile cap to provide reaction force; (2) The combination of soil grouting and multiple large-diameter spiral steel blades can effectively improve the anchoring force of the screw anchor; (3) There are various combinations of screw anchors, which can give full play to the bearing capacity of uneven soil layers; (4) The screw anchor can be recycled; (5) High construction efficiency and low construction cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an elevation view of the screw anchor reaction force pile pressing device of the present invention; Figure 2 It is a plan view of the screw anchor reaction force pile pressing device of the present invention; Figure 3 It is a construction schematic diagram of step S1 of the reaction force pile pressing method of the present invention; Figure 4 It is a construction schematic diagram of step S2 of the reaction force pile pressing method of the present invention; Figure 5 It is a construction schematic diagram of step S3 of the reaction force pile pressing method of the present invention; Figure 6 It is a construction schematic diagram of step S4 of the reaction force pile pressing method of the present invention; Figure 7 It is a construction schematic diagram of step S5 of the reaction force pile pressing method of the present invention; Figure 8 It is a construction schematic diagram of step S6 of the reaction force pile pressing method of the present invention; Figure 9 It is a construction schematic diagram of step S7 of the reaction force pile pressing method of the present invention; Figure 10 It is a construction schematic diagram of step S8 of the reaction force pile pressing method of the present invention; As Figures 1 - 10 shown, the marks in the figure are respectively represented as: Screw anchor 10, spiral steel blade 101, pile pressing base 20, longitudinal plate 201, transverse plate 202, limit nut 30, inner push rod 40, force transmission hoop 50, jack 60, reinforcement pile 70, connecting rod 80, grouting body 90, transverse connecting plate 100, longitudinal connecting plate 110. DETAILED DESCRIPTION OF THE INVENTION

[0016] The features of the present invention and other related features will be further described in detail below with reference to the accompanying drawings through examples for the understanding of those skilled in the same industry: Example: As Figures 1 - 10As shown in the figure, this embodiment relates to a screw anchor reaction pile pressing method applicable to foundation reinforcement, which utilizes a screw anchor reaction pile pressing device. The screw anchor reaction pile pressing device is composed of a reaction device and a pile pressing device. The reaction pile pressing method mainly includes the following steps: S1: As Figure 3 shown in the figure, several screw anchors 10 are drilled into the soil within the pile pressing range.

[0017] Among them, as Figures 1 - 2 shown in the figure, according to the pile pressing load required for foundation reinforcement and the soil layer conditions, screw anchors 10 with different specifications, sizes, lengths, and quantities are selected. Specifically, in the case of good shallow soil properties, a combination of small - specification and large - quantity screw anchors is selected to make full use of the shallow soil; in the case of poor shallow soil properties, a combination of large - specification and small - quantity screw anchors is selected to make full use of the deep soil; in the case of uneven soil layers, a combination of large - specification and small - specification screw anchors is selected to give full play to the bearing capacity of the uneven soil layer. Multiple large - diameter spiral steel blades 101 are arranged at the bottom of the screw anchor 10 to improve the anchoring force of the screw anchor 10. After determining the screw anchor 10, a torque is applied to the end of the screw anchor 10 so that the screw anchor 10 can be normally screwed, the spiral steel blade 101 can smoothly cut the soil, and it is driven into the predetermined soil layer. The end of the screw anchor 10 protrudes from the ground by an appropriate length (to facilitate the subsequent installation of the pile pressing base 20), and the first limiting nut 30 is installed.

[0018] S2: As Figure 4 shown in the figure, the soil around the screw anchor 10 is grouted for reinforcement to form a grouted body 90.

[0019] Among them, the grouting reinforcement area is about 2m outside the area where the screw anchor 10 is set.

[0020] S3: As Figure 5 shown in the figure, a pile pressing base 20 is erected on the grouted body 90, and the top of the screw anchor 10 is connected and fixed to the pile pressing base 20 to form a reaction device.

[0021] Among them, as Figures 1 - 2 shown in the figure, the pile pressing base 20 includes two relatively arranged longitudinal plates 201 and two relatively arranged transverse plates 202. The two transverse plates 202 are located in the middle of the two longitudinal plates 201, and the screw anchor 10 is connected to the end of the longitudinal plate 201. In this embodiment, two screw anchors 10 are provided at each end of each longitudinal plate 201. The two screw anchors 10 are respectively a long screw anchor and a short screw anchor, and the long screw anchor is relatively close to the corresponding end of the longitudinal plate 201, and the short screw anchor is relatively far from the corresponding end of the longitudinal plate 201.

[0022] A second limiting nut 30 is installed on the top of the spiral anchor 10, and the pile base 20 is fixed by the first limiting nut 30 and the second limiting nut 30. The first limiting nut 30 and the second limiting nut 30 are respectively tightly attached to the bottom surface and the top surface of the pile base 20.

[0023] S4: Figure 6 As shown, a pile driving device is installed on the pile driving base 20 .

[0024] Among them, Figures 1 - 2 As shown, the pile driving device includes a jack 60, an inner push rod 40, a force transmission hoop 50, a connecting rod 80, a transverse connecting plate 100 and a longitudinal connecting plate 110. The upper end and the lower end of the inner push rod 40 are respectively connected to the jack 60 and the force transmission hoop 50. The force transmission hoop 50 is used to clamp and reinforce the pile body. There are four connecting rods 80, and the four connecting rods 80 are arranged in a rectangular shape. The four connecting rods 80 are respectively arranged on two transverse plates 202 of the pile driving base 20. The top ends of the four connecting rods 80 are connected in the transverse and longitudinal directions by two transverse connecting plates 100 and two longitudinal connecting plates 110, respectively. There are two jacks 60, and the two jacks 60 are respectively installed on the two transverse connecting plates 100. The lower end of the inner push rod 40 passes through the transverse connecting plate 100 to be connected to the force transmission hoop 50, and the force transmission hoop 50 is respectively sleeved on the four connecting rods 80. The jack 60 drives the force transmission hoop 50 to move vertically through the inner push rod 40 , and the connecting rod 80 can guide the force transmission hoop 50 .

[0025] S5: Figure 7 As shown, the force transmission hoop 50 is used to clamp the first section of the reinforced pile body, and the jack 60 drives the force transmission hoop 50 to move downward through the inner push rod 40 to press the first section of the reinforced pile body into the soil step by step to complete the pile pressing operation; the next section of the reinforced pile body is connected, and the pile pressing operation is repeated until all the reinforced pile bodies are pressed into the soil to form a reinforced pile 70.

[0026] Among them, the length of each section of the reinforced pile body is determined according to the construction operation space, the reinforced pile body is placed in the pile driving device and accurately positioned (the reinforced pile body is located in the space formed by the two longitudinal plates 201 and the two transverse plates 202 of the pile driving base 20), the force transmission hoop 50 is connected with the reinforced pile body in an embrace, and the friction force of the force transmission hoop 50 is adjusted by the pre-tightening of the bolts.

[0027] Pressing the reinforced pile body into the soil step by step means that when the reinforced pile body is pressed into the soil to a certain distance, the inner push rod 40 reaches the maximum stroke, the connection between the force transmission hoop 50 and the reinforced pile body is released, the inner push rod 40 retreats to the minimum stroke, the force transmission hoop 50 is reconnected to the reinforced pile body, and the reinforced pile body continues to be pressed into the soil.

[0028] S6: Figure 8As shown, the pile pressing device and the pile pressing base 20 are removed in sequence.

[0029] S7: As Figure 9 shown, the reinforcement pile 70 is sealed.

[0030] Among them, sealing the pile means that the reinforcement pile 70 is effectively connected to the existing structure through measures such as implanting steel bars, chiseling the concrete surface, and pouring grouting material. After the slurry solidifies, the reinforcement pile 70 and the existing structure are connected by the slurry to form a stable whole. The reinforcement pile 70 serves as the new foundation of the reinforced building and complements the existing structure, greatly improving the building safety.

[0031] S8: As Figure 10 shown, the screw anchor 10 is rotated and pulled out in the opposite direction of the direction in which the screw anchor 10 drills into the soil within the pile pressing range, and the pores formed by pulling out the screw anchor 10 are grouted and sealed, and the ground surface returns to its original state.

[0032] Among them, the strength of the grouting body 90 can be controlled by the water-cement ratio in actual construction. Grouting is only an auxiliary means, and it is only necessary to appropriately improve the bearing capacity of the soil. The main purpose is to appropriately improve the anchoring force of the screw anchor 10, but it will be less than the shear force when the screw anchor 10 is rotated and pulled out in the reverse direction. Therefore, the grouting body 90 will be shear-damaged when the screw anchor 10 is rotated in the reverse direction, so that the screw anchor 10 can be pulled out. The residual grouting body 90 on the screw anchor 10 will be cleaned by mechanical knocking. After the screw anchor 10 is cleaned, appropriate maintenance is carried out for subsequent use.

[0033] The beneficial technical effects of this embodiment are as follows: (1) Simple structure and convenient construction, without the need for a raft or a pile cap to provide reaction force; (2) The combination of soil grouting and multiple large-diameter spiral steel blades can efficiently improve the anchoring force of the screw anchor; (3) There are various combinations of screw anchors, which can give full play to the bearing capacity of uneven soil layers; (4) The screw anchor can be recycled; (5) High construction efficiency and low construction cost.

[0034] Although the above embodiments have described in detail the concept and embodiments of the present invention with reference to the accompanying drawings, those of ordinary skill in the art can recognize that various improvements and transformations can still be made to the present invention without departing from the scope defined by the claims. Therefore, they are not elaborated one by one here.

Claims

1. A spiral anchor reaction pile method suitable for foundation reinforcement, characterized in that The reaction pile pressing method comprises: S1: Drill several screw anchors into the soil within the range of pile pressure; S2: Grouting and reinforcing the soil around the spiral anchor to form a grouting body; S3: setting up a pile pressing base on the grouting body, and connecting and fixing the top of the spiral anchor to the pile pressing base to form a reaction force device; S4: Installing a pile pressing device on the pile pressing base; The pile driving device comprises a jack, an inner push rod and a force transmission hoop, the upper end and the lower end of the inner push rod are respectively connected to the jack and the force transmission hoop, and the force transmission hoop is used to clamp and reinforce the pile body; S5: The force transmission hoop is used to clamp the first section of the reinforced pile body, and the jack drives the force transmission hoop to move downward through the inner push rod, so as to press the first section of the reinforced pile body into the soil step by step to complete the pile pressing operation; the next section of the reinforced pile body is connected, and the pile pressing operation is repeated until all the reinforced pile bodies are pressed into the soil to form a reinforced pile; S6: dismantling the pile pressing device and the pile pressing base in sequence; S7: sealing the reinforcement piles; S8: pulling out the spiral anchor by rotating it in the direction opposite to the direction in which the spiral anchor is drilled into the soil within the pile driving range, and sealing the pores caused by pulling out the spiral anchor by grouting.

2. A spiral anchor reaction pile method suitable for foundation reinforcement as claimed in claim 1, characterized in that The pile driving device also includes connecting rods, transverse connecting plates and longitudinal connecting plates. There are four connecting rods and the four connecting rods are arranged in a rectangular shape. The top ends of the four connecting rods are connected in the transverse and longitudinal directions respectively by two transverse connecting plates and two longitudinal connecting plates. There are two jacks and the two jacks are respectively installed on the two transverse connecting plates. The lower end of the inner push rod passes through the transverse connecting plate and is connected to the force transmission hoop. The force transmission hoop is respectively mounted on the four connecting rods.

3. A spiral anchor reaction pile method suitable for foundation reinforcement as claimed in claim 2, characterized in that The pile driving base includes two relatively arranged longitudinal plates and two relatively arranged transverse plates, the two transverse plates are located in the middle of the two longitudinal plates, the reinforced pile body is located in the space formed by the two longitudinal plates and the two transverse plates, the four connecting rods are respectively arranged on the two transverse plates in pairs, and the spiral anchor is connected to the end of the longitudinal plate.

4. A spiral anchor reaction pile method suitable for foundation reinforcement as claimed in claim 1, characterized in that A plurality of large-diameter spiral steel blades are arranged at the bottom of the spiral anchor.

5. A spiral anchor reaction pile method suitable for foundation reinforcement as claimed in claim 1, characterized in that In step S1, a first limiting nut is installed on the top of the spiral anchor.

6. A spiral anchor reaction pile method suitable for foundation reinforcement as claimed in claim 5, characterized in that In step S3, a second limiting nut is installed on the top of the spiral anchor, and the pile driving base is fixed by the first limiting nut and the second limiting nut.

7. A spiral anchor counterforce pile method suitable for foundation reinforcement as claimed in claim 1, characterized in that In step S5, pressing the reinforced pile body into the soil step by step means that when the reinforced pile body is pressed into the soil to a certain distance, the inner push rod reaches the maximum stroke, the connection between the force transmission hoop and the reinforced pile body is released, the inner push rod retreats to the minimum stroke, the force transmission hoop is reconnected to the reinforced pile body, and the reinforced pile body continues to be pressed into the soil.

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