Construction method of bored pile and bored pile

Abstract

The invention discloses a construction method of a bored pile and the bored pile, and relates to the technical field of pile foundation construction.The construction method of the bored pile comprises the steps that a stratum is excavated downwards to the first depth to form a first hole section with the hole diameter being the first diameter; a wall protecting cylinder is installed in the first hole section; the stratum is excavated downwards from the bottom of the first hole section to a second depth to form a second hole section with the hole diameter being a second diameter; expanding the second hole section to increase the aperture of the second hole section; the step of expanding the second hole section to increase the hole diameter of the second hole section is repeatedly executed until the hole diameter of the second hole section is increased to the first diameter, and the first hole section and the second hole section are communicated to form a pile hole; a reinforcement cage is installed in the pile hole; and concrete is poured into the pile hole. According to the construction method of the drilled pile, when pile foundation construction is conducted on a rock-soil stratum with high structural strength, pile hole forming is easy, and the construction difficulty is low.

Description

Technical Field

[0001] The present invention relates to the technical field of pile foundation construction, in particular to a construction method of a bored pile and a bored pile. Background Art

[0002] In the current pile foundation construction process, when encountering rock formations with high structural strength such as moderately weathered sandstone, basalt or high-density gravel layers, it is difficult to use traditional mechanical drilling technology to excavate these rock formations to form pile holes, and the construction difficulty is relatively high. Summary of the Invention

[0003] The main purpose of the present invention is to provide a bored pile construction method and bored pile, aiming to solve the technical problem that pile hole forming is difficult and construction is difficult when pile foundation construction is carried out in rock and soil strata with relatively high structural strength.

[0004] To achieve the above-mentioned object, the bored pile construction method proposed by the present invention comprises:

[0005] Bury the wall protection tube in the stratum from the surface downward;

[0006] Excavating the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter; wherein the hole diameter of the wall protection tube is larger than the first diameter;

[0007] Installing a wall protection tube in the first hole section;

[0008] excavating the stratum downward from the bottom of the first hole section to a second depth to form a second hole section having a second diameter; wherein the first diameter is greater than the second diameter, and the first hole section and the second hole section are connected to form a pile hole;

[0009] expanding the second hole segment to increase the hole diameter of the second hole segment;

[0010] Repeating the step of expanding the second hole segment to increase the diameter of the second hole segment until the diameter of the second hole segment increases to the first diameter, and the first hole segment and the second hole segment are connected to form a pile hole;

[0011] installing a steel cage in the pile hole;

[0012] pouring concrete into the pile hole;

[0013] When the concrete in the pile hole solidifies, the bored pile construction is completed.

[0014] In one embodiment, the step of expanding the second hole segment to increase the diameter of the second hole segment includes:

[0015] The aperture of the second hole section is expanded by a preset length.

[0016] In one embodiment, the preset length is A, wherein 0.3m≤A≤0.5m.

[0017] In one embodiment, before the step of installing the steel cage in the pile hole, the method further comprises:

[0018] The drilling debris in the pile hole is fished out.

[0019] In one embodiment, after the step of removing the drilling debris from the pile hole, the method further comprises:

[0020] pouring slurry into the pile hole;

[0021] The slurry in the pile hole is pumped out to complete the cleaning of the pile hole.

[0022] In one embodiment, the step of pumping out the slurry in the pile hole to complete the cleaning of the pile hole includes:

[0023] The mud in the pile hole is pumped out, and fresh mud is continuously poured into the pile hole while the mud is being pumped out, so that the mud level in the pile hole remains constant.

[0024] In one embodiment, the step of excavating the stratum downward in the retaining wall tube to a first depth to form a first hole section with a first diameter includes:

[0025] Using a drill bit to dig the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter;

[0026] The step of excavating the stratum downward from the bottom of the first hole section to a second depth to form a second hole section with a second diameter includes:

[0027] A drill bit is used to drill downward from the bottom of the first hole section into the ground formation to a second depth to form a second hole section with a second diameter.

[0028] In one embodiment, the step of using a drill bit to excavate the stratum downward in the retaining wall tube to a first depth to form a first hole section with a first diameter includes:

[0029] Using the drill bit to excavate the stratum downwards from the ground surface to a first preset depth in the retaining wall tube;

[0030] Continuing to drill downward into the formation to a first preset depth;

[0031] Repeating the step of continuing to drill downward to a preset depth of the first formation until a first hole section having a first diameter is formed by drilling to the first depth;

[0032] The step of drilling the stratum downward from the bottom of the first hole section to a second depth using a drill bit to form a second hole section with a second diameter comprises:

[0033] Drilling downward from the bottom of the first hole section to a second preset depth using the drill bit;

[0034] Continuing to drill downward to a second preset depth of the formation;

[0035] The step of continuing to drill downward to a second preset depth of the formation is repeated until the second depth is reached and a hole section having a diameter of the second hole is formed.

[0036] In one embodiment, the first preset depth is B, and the second preset depth is C; wherein, 0.5m≤B≤0.8m, 0.5m≤C≤0.8m.

[0037] The present invention also provides a bored pile, which is constructed using the above-mentioned bored pile construction method.

[0038] The technical solution of the present invention is to first excavate downward to the top of the rock and soil stratum with higher structural strength to form a first hole section with a hole diameter equal to the hole diameter of the pile hole to be formed, so as to quickly and efficiently complete the construction of the part of the pile hole that is not located in the rock and soil stratum with higher structural strength, and then preliminarily excavate a second hole section with a hole diameter significantly smaller than the hole diameter of the pile hole to be formed in the rock and soil stratum with higher structural strength. Since the hole diameter of the second hole section is smaller, it is simpler and more convenient to excavate in the rock and soil stratum with higher structural strength, and the forming is faster. Then, the hole diameter of the second hole section can be expanded to the first diameter through multiple expansions. The first hole section and the second hole section, both of which have a hole diameter of the first diameter, are connected to complete the construction of the pile hole. The pile hole is simple and convenient to form, and the construction difficulty is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0040] Figure 1 A schematic flow chart of the bored pile construction method provided by the present invention;

[0041] Figure 2 A schematic diagram of the structure of a bored pile construction method and a bored pile in one embodiment of the present invention, in which the pile hole is in an unexpanded state in the second hole section;

[0042] Figure 3This is a schematic diagram of the structure of a bored pile construction method and a bored pile embodiment provided by the present invention, with the pile hole in a state where the second hole section is fully expanded.

[0043] Description of Figure Numbers:

[0044] 10. Pile hole; 20. First hole section; 30. Second hole section; 40. Rock and soil stratum.

[0045] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0046] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0047] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0048] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of such features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0049] In the current pile foundation construction process, when encountering rock formations with high structural strength such as moderately weathered sandstone, basalt or high-density gravel layers, it is difficult to use traditional mechanical drilling technology to excavate these rock formations to form pile holes, and the construction difficulty is relatively high.

[0050] The invention provides a construction method of bored piles.

[0051] See also Figures 1 to 3 In one embodiment of the present invention, the bored pile construction method includes:

[0052] Step S100: burying a wall protection tube in the stratum from the surface downward;

[0053] By setting up a wall protection tube in the stratum where construction is required, the stratum can be reinforced to improve the stability of subsequent construction.

[0054] Step S200: excavating the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter; wherein the hole diameter of the wall protection tube is larger than the first diameter;

[0055] A first hole section 20 with a first diameter is formed by excavating downwardly along the retaining wall tube to a first depth, so that the first hole section 20 can penetrate the stratum above the rock formation 40 with higher structural strength, thereby directly excavating above the rock formation 40 with higher structural strength to form the first hole section 20 with a diameter matching the pile hole 10.

[0056] Step S300: excavating the stratum downward from the bottom of the first hole section to a second depth to form a second hole section with a second diameter; wherein the first diameter is greater than the second diameter, and the first hole section and the second hole section are connected to form a pile hole;

[0057] The rock and soil stratum 40 with relatively high structural strength below the first hole section 20 is excavated downward from the bottom of the first hole section 20 so that the bottom depth of the second hole section 30 is the bottom depth of the pile hole 10 to be formed. Since the hole diameter of the preliminarily formed second hole section 30 is smaller than that of the pile hole 10, the excavation of the second hole section 30 is relatively simple and convenient.

[0058] Step S400, expanding the second hole segment to increase the aperture of the second hole segment;

[0059] Step S500, repeating step S400 until the diameter of the second hole segment increases to the first diameter;

[0060] By gradually expanding the second hole section 30 in multiple steps, the diameter of the second hole section 30 can be gradually increased to the diameter of the pile hole 10 to be formed. Once the diameter of the second hole section 30 has increased to the diameter of the pile hole 10 to be formed, that is, to the first diameter, the first hole section 20 and the second hole section 30 jointly form the pile hole 10, thereby completing the construction of the pile hole 10. Furthermore, compared to a single step of expanding the second hole section 30, the multiple steps of gradually expanding the second hole section 30 are simpler and more convenient, and have less impact on the first hole section 20 above the second hole section 30. This further reduces the possibility of instability in the first hole section 20 caused by excavating the second hole section 30, and provides higher reliability.

[0061] Step S600, installing a steel cage in the pile hole;

[0062] Step S700, pouring concrete into the pile hole;

[0063] Step S800: After the concrete in the pile hole solidifies, the bored pile construction is completed.

[0064] Then a steel cage is installed in the pile hole 10 and concrete is poured. After the concrete in the pile hole 10 solidifies, the construction of the bored pile is completed.

[0065] The technical solution of the present invention is to first excavate downward to the top of the rock and soil stratum 40 with higher structural strength to form a first hole section 20 with a hole diameter equal to the hole diameter of the pile hole 10 to be formed, so as to quickly and efficiently complete the construction of the portion of the pile hole 10 not located in the rock and soil stratum 40 with higher structural strength. Then, a second hole section 30 with a hole diameter significantly smaller than the hole diameter of the pile hole 10 to be formed is preliminarily excavated in the rock and soil stratum 40 with higher structural strength. Since the hole diameter of the second hole section 30 is smaller, it is simpler and more convenient to excavate in the rock and soil stratum 40 with higher structural strength, and the forming is faster. Then, the hole diameter of the second hole section 30 can be expanded to the first diameter through multiple expansions. The first hole section 20 and the second hole section 30, both of which have the first diameter, are connected to complete the construction of the pile hole 10. The pile hole 10 is simple and convenient to form, and the construction difficulty is relatively low.

[0066] In one embodiment of the present invention, step S400 includes:

[0067] Step S400: expanding the aperture of the second hole segment by a preset length.

[0068] Specifically, each time the second hole section 30 is expanded according to a preset length, standardized operation of expanding the second hole section 30 can be achieved. Through standardized operation, the hole diameter deviation caused by operation fluctuations can be reduced, the efficiency and refinement of bored pile construction can be achieved, local over-expansion or under-expansion can be avoided, and the qualified rate of the verticality and diameter of the pile hole 10 can be guaranteed.

[0069] In one embodiment of the present invention, the preset length is A, wherein 0.3m≤A≤0.5m.

[0070] Furthermore, the preset length of each expansion of the second hole section 30 is set between 0.3m and 0.5m, which has little impact on the first hole section 20 above the second hole section 30, effectively reducing the possibility of instability of the first hole section 20 due to excavation of the second hole section 30, while still ensuring a high hole expansion efficiency and avoiding an increase in the construction period due to excessive hole expansion times.

[0071] In one embodiment of the present invention, before step S600, the method further includes:

[0072] Step A100: fishing out the drill cuttings in the pile hole.

[0073] Specifically, after the pile hole 10 is constructed, the drilled debris in the pile hole 10 is removed, making it easier to install the steel cage in the pile hole 10. This prevents the drilled debris in the pile hole 10 from obstructing the installation of the steel cage, making installation of the steel cage more convenient. Furthermore, the possibility of abnormal installation of the steel cage or quality problems with the concrete can be effectively reduced, thereby improving the quality of the bored pile.

[0074] In one embodiment of the present invention, after step A100, the method further includes:

[0075] Step A110, pouring slurry into the pile hole;

[0076] In step A120, the slurry in the pile hole is pumped out to complete the cleaning of the pile hole.

[0077] Specifically, by pouring slurry into the pile hole 10 and then pumping out the slurry, the sediment in the pile hole 10 can be taken out, thereby further cleaning the pile hole 10 and further improving the forming quality of the bored pile.

[0078] In one embodiment of the present invention, step A120 includes:

[0079] Step A121: pumping out the mud in the pile hole, and continuously injecting fresh mud into the pile hole while pumping out the mud, so that the mud level in the pile hole remains unchanged.

[0080] Furthermore, while slurry is being pumped out of the pile hole 10, fresh slurry is continuously injected into the pile hole 10 to replenish the slurry in the pile hole 10, thereby maintaining a constant slurry level in the pile hole 10. This provides support for the wall of the pile hole 10 and prevents collapse of the pile hole 10. Furthermore, the circulating flow created by pumping out the slurry and injecting fresh slurry into the pile hole 10 accelerates the floating speed of sediment in the pile hole 10, thereby effectively improving hole cleaning efficiency.

[0081] In one embodiment of the present invention, step S200 includes:

[0082] Step S210: using a drill bit to excavate the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter;

[0083] Step S300 includes:

[0084] Step S310: using a drill bit to drill downward from the bottom of the first hole section into the stratum to a second depth to form a second hole section with a second diameter.

[0085] Specifically, the first hole section 20 and the second hole section 30 can be formed by directly drilling into the stratum with a drill bit, which is simple and convenient, and has a high hole-forming efficiency, thereby effectively shortening the construction period.

[0086] In one embodiment of the present invention, step S210 includes:

[0087] Step S211, using the drill bit to excavate the stratum downward from the ground surface to a first preset depth in the retaining wall tube;

[0088] Step S212, continue drilling downward to the first preset depth of the formation;

[0089] Step S213, repeating step S212 until drilling reaches the first depth to form a first hole section with a first diameter;

[0090] Step S310 includes:

[0091] Step S311, using the drill bit to drill downward from the bottom of the first hole section to a second preset depth;

[0092] Step S312, continue drilling downward to a second preset depth of the formation;

[0093] Step S313, repeating step S312 until drilling reaches a second depth and forming a hole with a diameter of the second hole section.

[0094] Furthermore, when the drill bit is used to drill the formation to form the first hole section 20, the drilling is performed in multiple passes, each time drilling downward to a first preset depth. When the drill bit is used to drill the formation to form the second hole section 30, the drilling is performed in multiple passes, each time drilling downward to a second preset depth. Forming both the first pile hole 10 and the second pile hole 10 in multiple passes maintains a stable drill bit torque and axial force, avoids excessive load on the drill bit, and prolongs the service life of the drill bit.

[0095] In one embodiment of the present invention, the first preset depth is B, and the second preset depth is C; wherein, 0.5m≤B≤0.8m, 0.5m≤C≤0.8m.

[0096] Specifically, setting the first preset depth and the second preset depth to 0.5m to 0.8m can effectively avoid excessive load on the drill bit, effectively improve the service life of the drill bit, and avoid the excavation of the first hole section 20 and the second hole section 30 taking a long time due to insufficient drilling depth each time, thereby ensuring high construction efficiency.

[0097] The present invention also proposes a bored pile, which is constructed using the above-mentioned bored pile construction method. The steps of the bored pile construction method refer to the above-mentioned embodiment. Since this bored pile adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0098] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformation made by utilizing the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A method for constructing bored piles, characterized in that: The construction method comprises: Bury the wall protection tube in the stratum from the surface downward; Excavating the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter; wherein the hole diameter of the wall protection tube is larger than the first diameter; Excavating the stratum downward from the bottom of the first hole section to a second depth to form a second hole section with a second diameter; wherein the first diameter is greater than the second diameter; expanding the second hole segment to increase the hole diameter of the second hole segment; Repeating the step of expanding the second hole segment to increase the diameter of the second hole segment until the diameter of the second hole segment increases to the first diameter, and the first hole segment and the second hole segment are connected to form a pile hole; installing a steel cage in the pile hole; pouring concrete into the pile hole; When the concrete in the pile hole solidifies, the bored pile construction is completed.

2. The bored pile construction method according to claim 1, wherein: The step of expanding the second hole segment to increase the aperture of the second hole segment includes: The aperture of the second hole section is expanded by a preset length.

3. The bored pile construction method according to claim 2, wherein: The preset length is A, wherein 0.3m≤A≤0.5m.

4. The bored pile construction method according to claim 1, wherein: Before the step of installing the steel cage in the pile hole, the method further comprises: The drilling debris in the pile hole is fished out.

5. The bored pile construction method according to claim 4, wherein: After the step of fishing out the drilling debris in the pile hole, the method further comprises: pouring slurry into the pile hole; The slurry in the pile hole is pumped out to complete the cleaning of the pile hole.

6. The bored pile construction method according to claim 5, characterized in that: The step of pumping out the slurry in the pile hole to complete the cleaning of the pile hole includes: The mud in the pile hole is pumped out, and fresh mud is continuously poured into the pile hole while the mud is being pumped out, so that the mud level in the pile hole remains constant.

7. The bored pile construction method according to any one of claims 1 to 6, characterized in that: The step of excavating the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter includes: Using a drill bit to dig the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter; The step of excavating the stratum downward from the bottom of the first hole section to a second depth to form a second hole section with a second diameter includes: A drill bit is used to drill downward from the bottom of the first hole section into the ground formation to a second depth to form a second hole section with a second diameter.

8. The bored pile construction method according to claim 7, wherein: The step of using a drill bit to excavate the stratum downward in the wall protection tube to a first depth to form a first hole section with a first diameter includes: Using the drill bit to excavate the stratum downwards from the ground surface to a first preset depth in the retaining wall tube; Continuing to drill downward into the formation to a first preset depth; Repeating the step of continuing to drill downward to a preset depth of the first formation until a first hole section having a first diameter is formed by drilling to the first depth; The step of drilling the stratum downward from the bottom of the first hole section to a second depth using a drill bit to form a second hole section with a second diameter comprises: Drilling downward from the bottom of the first hole section to a second preset depth using the drill bit; Continuing to drill downward to a second preset depth of the formation; The step of continuing to drill downward to a second preset depth of the formation is repeated until the second depth is reached and a hole section having a diameter of the second hole is formed.

9. The bored pile construction method according to claim 8, wherein: The first preset depth is B, and the second preset depth is C; wherein, 0.5m≤B≤0.8m, 0.5m≤C≤0.8m.

10. A bored pile, characterized in that: The bored pile is constructed by using the bored pile construction method according to any one of claims 1 to 9.

Images