Cast-in-situ bored pile construction method capable of preventing soil squeezing

Abstract

The invention relates to a soil-squeezing-preventing cast-in-situ bored pile construction method which comprises the steps that a drilling machine is used for drilling a cast-in-situ pile hole, a cast-in-situ pile reinforcement cage is put into the cast-in-situ pile hole, a soil-squeezing-preventing ring is arranged at the set position of the cast-in-situ pile reinforcement cage in a sleeving mode, and an air bag is filled with fluid to set pressure through a pressure pump; cast-in-place pile concrete is poured into the cast-in-place pile hole to pour the cast-in-place pile reinforcement cage, the cast-in-place pile concrete and the cast-in-place pile reinforcement cage are poured together to form a cast-in-place pile body, after fluid is injected into the soil squeezing prevention ring to reach the set pressure, precast pile penetration located around the cast-in-place pile hole is conducted, and after the cast-in-place pile concrete reaches the designed age, the cast-in-place pile reinforcement cage is closed. And the air bag is decompressed, the soil squeezing prevention ring is taken down, and cement grout is injected into the area where the soil squeezing prevention ring is located for filling. The invention aims to provide the construction method for the cast-in-situ bored pile capable of preventing soil squeezing, which can be used for simultaneously constructing the cast-in-situ bored pile and the prefabricated pipe pile, so that the problem that the existing cast-in-situ bored pile can only be constructed after the prefabricated pipe pile is constructed is solved.

Description

Technical Field

[0001] The invention relates to the technical field of foundation pile construction, and in particular to a soil-squeezing-proof bored cast-in-place pile construction method. Background Art

[0002] Precast pipe piles and bored cast-in-place piles have become widely used foundation forms in engineering due to their respective advantages. Many large-scale projects often use both foundation forms at the same time. Precast pipe piles, which are more convenient to construct, are used for locations with lower load-bearing requirements, while bored cast-in-place piles are used for locations with higher load-bearing requirements. However, there is a soil squeezing effect during the penetration construction of precast pipe piles, which will have an adverse effect on the adjacent bored cast-in-place piles. In particular, the soil squeezing effect caused by large-scale penetration construction will cause problems such as extrusion fracture and necking of the bored cast-in-place piles that have not reached the age limit, which will not only have a significant impact on the construction quality, but also affect the construction period. For this reason, when precast pipe piles and bored cast-in-place piles are used as the foundation at the same time, the precast pipe piles are constructed first, and then the bored cast-in-place piles are constructed, which leads to a long construction period. Summary of the invention

[0003] The invention aims to provide a soil-squeezing-proof bored cast-in-place pile construction method which enables bored cast-in-place piles and prefabricated pipe piles to be constructed simultaneously, thereby solving the problem that the existing bored cast-in-place piles can only be constructed after the prefabricated pipe piles are constructed.

[0004] The above technical problems are solved by the following technical solutions: a method for constructing bored piles to prevent soil squeezing, characterized in that the bored piles include a bored pile body with a squeezed section at the upper end and an anti-squeezing ring sleeved on the squeezed section, the anti-squeezing ring is formed by splicing four air bags distributed along the circumference of the bored pile body, and the air bags are provided with valves; the process of bored pile construction is: using a drilling rig to drill a bored pile hole, lowering a bored pile steel cage into the bored pile hole, sleeve the anti-squeezing ring onto the bored pile At the set position of the steel cage, the air bag is filled with fluid to the set pressure using a pressure pump, the bored pile concrete is poured into the bored pile hole to cast the bored pile steel cage, the bored pile concrete and the bored pile steel cage are poured together to form the bored pile body, the anti-squeezing ring is filled with fluid to the set pressure and the precast piles located around the bored pile hole are penetrated, after the bored pile concrete reaches the designed age, the air bag is depressurized and the anti-squeezing ring is removed, and cement slurry is penetrated into the area where the anti-squeezing ring is located for filling.

[0005] Preferably, the wall of the airbag facing the squeezed section is a steel plate structure, the wall slopes of the adjacent airbags facing the squeezed section are butted together, the wall of the airbag away from the squeezed section is a steel plate structure, the end face of the wall of the airbag away from the squeezed section is provided with a butting slope, and the walls of the adjacent airbags away from the squeezed section are supported by the butting slope when they are butted together. The cast-in-place pile body can be reliably protected, and the squeezing on one side can be resisted by the airbag on the remaining side.

[0006] Preferably, the airbag comprises a rubber tube, one end of the rubber tube is sealed by the wall of the airbag facing the squeezed section, and the other end is sealed by the wall of the airbag away from the squeezed section, and the rubber tubes are spaced apart when the walls of adjacent airbags away from the squeezed section abut against each other, so as to avoid the rubber tubes from being damaged by wear when subjected to squeeze impact.

[0007] Preferably, the walls of the adjacent airbags away from the squeezed section are connected together by a vertically extending elastic sealing strip, which can prevent mud from entering and improve the reliability of protection.

[0008] Preferably, both ends of the outer surface of the wall of the airbag away from the squeezed section are provided with vertical card slots in the horizontal direction, and both sides of the elastic sealing strip are provided with card heads in the horizontal direction, and the card heads at both ends of the elastic sealing strip are correspondingly connected to the vertical card slots of the walls of the two adjacent airbags away from the squeezed section. The connection is convenient and reliable.

[0009] Preferably, a liquid bag is provided inside the air bag, and the liquid bags of adjacent air bags are connected together through energy dissipation tubes, so as to consume the extrusion energy when repeatedly impacted and extruded.

[0010] Preferably, the energy dissipation pipe comprises a plurality of energy dissipation sheet groups distributed along the length direction of the energy dissipation pipe, the energy dissipation sheet group comprises four energy dissipation sheets, one end of one energy dissipation sheet in the energy dissipation sheet group is hinged on the top wall of the energy dissipation pipe through an upper hinge shaft and is located between two upper limit blocks, one end of another energy dissipation sheet is hinged on the bottom wall of the energy dissipation pipe through a lower hinge shaft and is located between two lower limit blocks, one end of the remaining two energy dissipation sheets is hinged on the middle part of the height direction of the front and rear side walls of the energy dissipation pipe through a middle hinge shaft and is located between two middle limit blocks, the upper limit is used to keep the one energy dissipation sheet at a set inclination angle, and the one The energy dissipation sheet can swing between the two upper limit blocks with the upper hinge axis as the axis, the lower limit is used to keep the other energy dissipation sheet at a set tilt angle, the other energy dissipation sheet can swing between the two lower limit blocks with the lower hinge axis as the axis, the one energy dissipation sheet is aligned with the other energy dissipation sheet, the middle limit block is used to keep the remaining two energy dissipation sheets at a set opening angle, the remaining two energy dissipation sheets can rotate between the two middle limit blocks, the remaining two energy dissipation sheets are located on the upper and lower sides of the middle limit block, and a plurality of resistance-increasing teeth are provided on the two side surfaces of the energy dissipation plate. A specific structure of an energy dissipation pipe is provided, which has a good energy dissipation effect and can automatically change direction to maintain the energy dissipation effect when the liquid flow direction changes.

[0011] Preferably, a groove is formed between the resistance increasing teeth and the energy dissipation plate at the rear end of the liquid flow direction in the energy dissipation pipe, which can improve the energy dissipation effect.

[0012] Preferably, the walls of adjacent airbags facing the squeezed section are clamped and abutted together by elastic shielding clips, and both ends of the inner surface of the walls of adjacent airbags facing the squeezed section are provided with vertical slots, and the two ends of the elastic shielding clips are correspondingly inserted into the vertical slots of the walls of the two airbags facing the squeezed section, so that the walls of the airbags facing the squeezed section can be conveniently and reliably maintained to abut against each other reliably.

[0013] Preferably, the cast-in-place pile reinforcement cage is provided with horizontal reinforcements, the air bags arranged opposite to each other are penetrated on the horizontal reinforcements, and the horizontal reinforcements are threadedly connected with anti-slip nuts, so as to prevent the anti-squeeze ring from being squeezed and causing the upward displacement phenomenon.

[0014] The present invention has the following advantages: the prefabricated pipe piles can be constructed synchronously with the bored cast-in-place pile construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a top view schematic diagram of bored cast-in-place piles; Figure 2 for Figure 1 A local enlarged schematic diagram of the A; Figure 3 for Figure 1 B-B cross-sectional view of FIG. Figure 4 for Figure 3 A local enlarged schematic diagram of point C; Figure 5 is a cross-sectional schematic diagram of an energy dissipation pipe; Figure 6 for Figure 5 A local enlarged schematic diagram of point D.

[0016] In the figure: cast-in-place pile body 1, anti-squeeze ring 2, air bag 3, rubber tube 4, wall 5 of the air bag facing the squeezed section side, wall 6 of the air bag away from the squeezed section side, elastic shielding clamp 7, vertical slot 8, longitudinal horizontal steel bar 9, transverse horizontal steel bar 10, longitudinal steel bar portion lock nut 11, transverse steel bar portion lock nut 12, abutment inclined surface 13, avoidance gap 14, elastic sealing strip 15, vertical slot 16, clamp head 17, liquid bag 29, energy dissipation pipe 18, one energy dissipation sheet 19, upper hinge shaft 20, top wall 21 of energy dissipation pipe, another energy dissipation sheet 22, lower hinge shaft 23, lower limit block 24, remaining two energy dissipation sheets 25, middle hinge shaft 26, resistance increasing tooth 27, groove 28, middle limit block 30, bottom wall 31 of energy dissipation pipe, rear side wall 32 of energy dissipation pipe, upper limit block 33, squeezed section 34. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figures 1 to 6A bored cast-in-place pile construction method for preventing soil extrusion, the bored cast-in-place pile comprises a cast-in-place pile body 1, and the upper end of the cast-in-place pile body is an extruded section 34. An anti-squeezing ring 2 is sleeved on the extruded section. The anti-squeezing ring is formed by splicing four air bags 3 distributed along the circumference of the cast-in-place pile body. The air bag is provided with an air valve. The air bag comprises a rubber tube 4. One end of the rubber tube facing the cast-in-place pile body is closed by a wall 5 on the side of the air bag facing the extruded section, and the other end is closed by a wall 6 on the side of the air bag away from the extruded section. The wall of the air bag facing the extruded section is a steel plate structure, and the wall slopes of the adjacent air bags facing the extruded section are butted together. The walls of the adjacent airbags facing the squeezed section are clamped and abutted together by elastic shielding clamps 7. The two ends of the inner surface of the wall of the adjacent airbags facing the squeezed section are provided with vertical slots 8 in the horizontal direction. The two ends of the elastic shielding clamps are correspondingly inserted into the vertical slots of the walls of the two airbags facing the squeezed section. The cast-in-place pile reinforcement cage is provided with longitudinal horizontal reinforcements 9 and transverse horizontal reinforcements 10. The airbags arranged opposite to each other in the front and back are inserted on the longitudinal horizontal reinforcements, and the airbags arranged opposite to each other in the left and right are inserted on the transverse horizontal reinforcements. The longitudinal reinforcement part anti-slip nuts 11 are threadedly connected to the longitudinal horizontal reinforcement, and the transverse reinforcement part anti-slip nuts 12 are threadedly connected to the transverse horizontal reinforcement. The wall of the airbag away from the squeezed section is a steel plate structure, and the end face of the wall of the airbag away from the squeezed section is provided with an abutting inclined surface 13. When the walls of the adjacent airbags away from the squeezed section are abutted together, they are supported by the abutting inclined surface. When the walls of the adjacent airbags on the side away from the squeezed section are butted together, the rubber tubes are spaced apart to form an escape gap 14. The walls of the adjacent airbags on the side away from the squeezed section are connected together by a vertically extending elastic sealing strip 15. Vertical clamping grooves 16 are provided at both ends of the outer surface of the wall of the airbag away from the squeezed section in the horizontal direction, and clamping heads 17 are provided on both sides of the elastic sealing strip in the horizontal direction. The clamping heads at both ends of the elastic sealing strip are correspondingly clamped in the vertical clamping grooves of the walls of the two adjacent airbags on the side away from the squeezed section.

[0019] A liquid bag 29 is arranged in the airbag, and the liquid bags of adjacent airbags are connected together by an energy dissipation pipe 18 so that the liquid bags in each airbag are connected. The energy dissipation pipe passes through the wall of the airbag facing the squeezed section. The energy dissipation pipe protrudes on the end surface of the wall of the airbag facing the squeezed section to form a sealing ring, so that the energy dissipation pipes on adjacent airbags are sealed and connected together when the wall of the airbag facing the squeezed section abuts together.

[0020] The energy dissipation pipe includes a plurality of energy dissipation sheet groups distributed along the length direction of the energy dissipation pipe, and the energy dissipation sheet group includes four energy dissipation sheets. One end of one energy dissipation sheet 19 in the energy dissipation sheet group is hinged on the top wall 21 of the energy dissipation pipe through an upper hinge shaft 20 and is located between two upper limit blocks 33, one end of another energy dissipation sheet 22 is hinged on the bottom wall 31 of the energy dissipation pipe through a lower hinge shaft 23 and is located between two lower limit blocks 24, and one end of the remaining two energy dissipation sheets 25 are hinged on the middle part of the height direction of the rear side wall 32 of the energy dissipation pipe and the front side wall of the energy dissipation pipe through a middle hinge shaft 26 and are located between two middle limit blocks 30. The upper limit is used to keep one energy dissipation sheet at a set tilt angle, and one energy dissipation sheet can swing between the two upper limit blocks with the upper hinge axis as the axis. The lower limit is used to keep another energy dissipation sheet at a set tilt angle, and the other energy dissipation sheet can swing between the two lower limit blocks with the lower hinge axis as the axis. One energy dissipation sheet is aligned with another energy dissipation sheet. The middle limit block is used to keep the remaining two energy dissipation sheets at a set opening angle, and the remaining two energy dissipation sheets can rotate between the two middle limit blocks. The remaining two energy dissipation sheets are located on the upper and lower sides of the middle limit block. A plurality of resistance-increasing teeth 27 are provided on the two side surfaces of the energy dissipation plate. A groove 28 located at the rear end of the liquid flow direction in the energy dissipation pipe is formed between the resistance-increasing teeth and the energy dissipation plate. When the liquid flow direction in the energy dissipation pipe changes, the resistance-increasing sheet swings and changes direction, so that energy dissipation can be performed while maintaining smooth flow.

[0021] The process of bored pile construction is as follows: use a drilling rig to drill a bored pile hole, lower the bored pile reinforcement cage into the bored pile hole, set an anti-squeezing ring on the set position of the bored pile reinforcement cage, use a pressure pump to fill the air bag with fluid to a set pressure, pour the bored pile concrete into the bored pile hole to cover the bored pile reinforcement cage, pour the bored pile concrete and the bored pile reinforcement cage together to form the bored pile body, and after the anti-squeezing ring is filled with fluid to a set pressure, penetrate the precast piles located around the bored pile hole, and after the bored pile concrete reaches the designed age, depressurize the air bag and remove the anti-squeezing ring, and penetrate cement slurry into the area where the anti-squeezing ring is located for filling.

Claims

1. A method for constructing bored piles to prevent soil extrusion, characterized in that: The bored pile comprises a bored pile body with an extruded section at the upper end and an anti-squeezing ring sleeved on the extruded section, wherein the anti-squeezing ring is formed by splicing four air bags distributed along the circumference of the bored pile body, and the air bags are provided with valves; the process of bored pile construction is: using a drilling rig to drill a bored pile hole, lowering a bored pile reinforcement cage into the bored pile hole, sleeve the anti-squeezing ring on a set position of the bored pile reinforcement cage, using a pressure pump to fill the air bag with fluid to a set pressure, pouring bored pile concrete into the bored pile hole to cast the bored pile reinforcement cage, pouring the bored pile concrete and the bored pile reinforcement cage together to form the bored pile body, and after the anti-squeezing ring is filled with fluid to the set pressure, the precast pile located around the bored pile hole is penetrated, and after the bored pile concrete reaches the designed age, the air bag is depressurized and the anti-squeezing ring is removed, and cement slurry is penetrated into the area where the anti-squeezing ring is located for filling.

2. The method for constructing bored piles to prevent soil extrusion according to claim 1, characterized in that: The wall of the airbag facing the squeezed section is a steel plate structure, and the wall slopes of the adjacent airbags facing the squeezed section are butted together. The wall of the airbag away from the squeezed section is a steel plate structure, and the end surface of the wall of the airbag away from the squeezed section is provided with a butting slope. When the walls of the adjacent airbags away from the squeezed section are butted together, they are supported by the butting slope. The cast-in-place pile body can be reliably protected, and the squeezing on one side can be resisted by the airbag on the remaining side.

3. The method for constructing bored piles to prevent soil extrusion according to claim 2, characterized in that: The airbag includes a rubber tube, one end of the rubber tube is closed by the wall of the airbag facing the squeezed section, and the other end is closed by the wall of the airbag away from the squeezed section, and the rubber tubes are spaced apart when the walls of adjacent airbags away from the squeezed section abut against each other, so as to avoid the rubber tubes from being damaged by wear when subjected to squeeze impact.

4. A method for constructing bored piles to prevent soil extrusion according to claim 2 or 3, characterized in that: The walls of the adjacent airbags away from the squeezed section are connected together by a vertically extending elastic sealing strip, which can prevent mud from entering and improve the reliability of protection.

5. The method for constructing bored piles to prevent soil extrusion according to claim 4, characterized in that: Vertical slots are provided at both ends of the outer surface of the wall of the airbag away from the squeezed section in the horizontal direction, and clamps are provided at both sides of the elastic sealing strip in the horizontal direction, and the clamps at both ends of the elastic sealing strip are correspondingly clamped in the vertical slots of the walls of the two adjacent airbags away from the squeezed section. The connection is convenient and reliable.

6. A method for constructing bored piles to prevent soil extrusion according to claim 2 or 3, characterized in that: The airbag is provided with a liquid bag, and the liquid bags of adjacent airbags are connected together through energy dissipation pipes, so as to consume the extrusion energy when repeatedly impacted and extruded.

7. The method for constructing bored piles to prevent soil extrusion according to claim 6, characterized in that: The energy dissipation pipe includes a plurality of energy dissipation sheet groups distributed along the length direction of the energy dissipation pipe, and the energy dissipation sheet group includes four energy dissipation sheets, one end of one energy dissipation sheet in the energy dissipation sheet group is hinged on the top wall of the energy dissipation pipe through an upper hinge shaft and is located between two upper limit blocks, one end of another energy dissipation sheet is hinged on the bottom wall of the energy dissipation pipe through a lower hinge shaft and is located between two lower limit blocks, and one end of the remaining two energy dissipation sheets is hinged on the middle part of the height direction of the front and rear side walls of the energy dissipation pipe through a middle hinge shaft and is located between two middle limit blocks, the upper limit is used to keep the energy dissipation sheet at a set inclination angle, and the energy dissipation sheet is located between two middle limit blocks. The energy dissipation plate can swing between the two upper limit blocks with the upper hinge axis as the axis, the lower limit is used to keep the other energy dissipation plate at a set inclination angle, the other energy dissipation plate can swing between the two lower limit blocks with the lower hinge axis as the axis, one energy dissipation plate is aligned with the other energy dissipation plate, the middle limit block is used to maintain the remaining two energy dissipation plates at a set opening angle, the remaining two energy dissipation plates can rotate between the two middle limit blocks, the remaining two energy dissipation plates are located on the upper and lower sides of the middle limit block, and a number of resistance-increasing teeth are provided on the two side surfaces of the energy dissipation plate. A specific structure of an energy dissipation pipe is provided, which has a good energy dissipation effect and can automatically change direction to maintain the energy dissipation effect when the direction of the liquid flow changes.

8. The method for constructing bored piles to prevent soil extrusion according to claim 7, characterized in that: A groove located at the rear end of the liquid flow direction in the energy dissipation pipe is formed between the resistance increasing teeth and the energy dissipation plate, which can improve the energy dissipation effect.

9. A method for constructing bored piles to prevent soil extrusion according to claim 2 or 3, characterized in that: The walls of the adjacent airbags facing the squeezed section are clamped and abutted together by elastic shielding clips, and both ends of the inner surface of the walls of the adjacent airbags facing the squeezed section are provided with vertical slots, and the two ends of the elastic shielding clips are correspondingly inserted into the vertical slots of the walls of the two airbags facing the squeezed section. It is convenient and reliable to maintain the walls of the airbags facing the squeezed section reliably abutting together.

10. A method for constructing bored piles to prevent soil extrusion according to claim 1, 2 or 3, characterized in that: The cast-in-place pile reinforcement cage is provided with horizontal reinforcements, and the air bags arranged oppositely are penetrated on the horizontal reinforcements, and the horizontal reinforcements are threadedly connected with anti-slip nuts, so as to ensure that the air bags of the anti-squeeze ring are reliably abutted together.

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