Complex geological pile foundation dry type rotary drilling hole collapse disposal construction method

Abstract

The invention belongs to a hole pile construction technology, and discloses a hole collapse treatment construction method for complex geological pile foundation dry type rotary excavating hole forming, which comprises the following steps: according to the diameter of a hole pile, a cylindrical steel casing with a corresponding size is processed, and the two ends of the steel casing are opened; backfill materials are injected into the hole piles till the backfill materials are flush with the bottoms of the hole collapse parts of the hole piles; a steel casing is placed at the upper end of the backfill material in the hole pile, and the steel casing and the hole pile are coaxially placed; filling a filling material into the steel casing; concrete is poured into a gap between the peripheral wall of the outer side of the steel casing and the hole collapse part; after concrete pouring is completed, the steel casing is pulled out of the concrete and discharged out of the hole pile; after the concrete is solidified, the filling materials and the backfill materials are cleaned and discharged out of the hole piles; the concrete is effectively supported by the filling material and the backfill material, so that the concrete is prevented from collapsing and falling off, the use amount of the concrete in the repairing process is effectively reduced, meanwhile, the waste of the concrete is reduced, and rotary drilling after repairing is completed is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of bored pile construction, and in particular relates to a construction method for dry-type rotary drilling of a hole in a complex geological pile foundation and disposal of a collapsed hole. Background Art

[0002] The method of drilling holes with a rotary drilling rig is mainly suitable for bored pile construction in clay, silt, sand, silty soil, artificial fill, pebbles, crushed stones and some rock formations; it is divided into wet rotary drilling and dry rotary drilling. Sufficient stabilizing fluid should be prepared before wet rotary drilling, usually mud, and the stabilizing fluid is used to form a protective wall. Dry rotary drilling is suitable for formations above the groundwater level or with poor water-bearing properties, such as plain fill, clay, silt and weathered rock formations that do not require protective wall measures;

[0003] Especially when dry drilling is adopted, a protective wall structure cannot be formed in the pile hole, and the self-stabilizing ability of the soil is relied upon. The hole is prone to collapse in the part passing through the strongly weathered layer or interlayer, especially when it rains, rainwater penetrates into the pile hole through the cracks, causing the broken part or the weak layer hole wall to become unstable; in the process of repairing the collapsed hole of the pile hole, a concrete filling method is usually adopted, but the filled concrete is prone to collapse or fall into the pile hole before solidification due to lack of support, which easily causes a large amount of concrete waste; therefore, there is a problem in the prior art that the concrete filling is prone to collapse during the repair of the collapsed hole of the pile hole, resulting in waste. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a construction method for dry rotary drilling of pile foundations in complex geology, which solves the problem in the prior art that concrete filling is prone to collapse during the repair of pile collapse, resulting in waste.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A construction method for dry rotary drilling of pile foundations in complex geology, comprising the following steps:

[0007] According to the diameter of the pile, a cylindrical steel casing of corresponding size is processed, and both ends of the steel casing are open;

[0008] Inject backfill into the pile hole until the backfill is flush with the bottom of the collapsed hole of the pile hole;

[0009] The steel casing is placed on the upper end of the backfill material in the pile hole, and the steel casing and the pile hole are placed coaxially;

[0010] Fill the steel casing with filler;

[0011] Pour concrete into the gap between the outer peripheral wall of the steel casing and the collapsed hole;

[0012] After the concrete pouring is completed, the steel casing is pulled out of the concrete and the bored pile is discharged;

[0013] After the concrete solidifies, clean out the filling material and backfill material and discharge them from the pile hole.

[0014] Filling the steel casing with filler material specifically includes the following steps:

[0015] A guide tube is inserted into the hole pile, and the lower end of the guide tube extends into the interior of the steel casing;

[0016] The upper end of the conduit extends to the outside of the hole pile and is connected to the hopper;

[0017] According to the volume of the steel casing, pour the corresponding volume of filler into the hopper;

[0018] The fill material is injected through the conduit and fills the steel casing.

[0019] The diameter of the bored pile is larger than the diameter of the outer circumferential wall of the steel casing. Suppose the difference between the diameter of the bored pile and the diameter of the outer circumferential wall of the steel casing is S, and the diameter of the outer circumferential wall of the conduit is N, S≥N.

[0020] The material of the backfill material is slag, and the particle size of the slag used near the collapsed hole is smaller than the particle size of the slag used near the bottom of the pile.

[0021] The filling material is crushed stone or sand.

[0022] Pouring concrete into the gap between the outer peripheral wall of the steel casing and the collapsed hole specifically includes the following steps:

[0023] Insert the lower end of the conduit into the gap between the outer peripheral wall of the steel casing and the collapsed hole;

[0024] Measure the height difference L between the upper and lower ends of the collapsed hole by measuring the rope;

[0025] If the height difference L is less than or equal to the length of the steel casing, concrete is poured directly into the gap between the steel casing and the collapsed hole through the hopper and the conduit until the upper end surface of the concrete is higher than the upper end of the collapsed hole;

[0026] If the height difference L is greater than the length of the steel casing, pour concrete in sections until the upper end surface of the concrete is higher than the upper end of the collapsed hole.

[0027] The concrete is poured in sections until the upper end surface of the concrete is higher than the upper end of the collapsed hole, which specifically includes the following steps:

[0028] S1. Pour concrete into the gap between the steel casing and the collapsed hole through the hopper and the conduit until the upper end surface of the concrete is lower than or equal to the upper end surface of the steel casing;

[0029] S2. Pull the steel casing upward along the axial direction of the steel casing, and the distance the steel casing moves upward is less than or equal to the length of the steel casing;

[0030] S3. Fill the steel casing with filler material through the hopper and the conduit until the filler material fills the steel casing again;

[0031] S4. Pour concrete into the gap between the steel casing and the collapsed hole through the hopper and the conduit until the upper end surface of the concrete is lower than or equal to the upper end surface of the steel casing;

[0032] S5. Repeat S2 to S4 continuously until the upper end surface of the concrete exceeds the upper end of the collapsed hole.

[0033] A lifting rod is provided on the steel casing, and both ends of the lifting rod are fixed to the upper end of the steel casing.

[0034] Beneficial effects of the present invention:

[0035] The backfill material is used to backfill the part of the bored pile located at the lower end of the collapsed hole, and then the filling material is filled into the steel casing, and concrete is filled into the gap between the outer side of the steel casing and the collapsed hole. When the concrete filling is completed, the steel casing is immediately pulled out of the concrete, and the steel casing is lifted out of the bored pile. When the steel casing is pulled out of the concrete, the filling material in the steel casing continues to remain between the concrete to support the concrete on the surrounding side. After the concrete solidifies, the repair of the collapsed hole is completed. After the repair of the collapsed hole is completed, rotary drilling is performed to clean and discharge the filling material and backfill material from the bored pile, so as to facilitate the subsequent reuse of the filling material and backfill material. When the collapsed hole is repaired by the method, the concrete is effectively supported by the filling material and the backfill material to avoid concrete collapse and falling, effectively reducing the amount of concrete used in the repair process, while also reducing the waste of concrete, and facilitating rotary drilling after the repair is completed. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 It is a schematic diagram of placing a steel casing in a pile hole of the present invention;

[0038] Figure 2 It is a schematic diagram of the state of filling the filling material in the steel casing of the present invention;

[0039] Figure 3 It is a schematic diagram of the state of concrete filling in the collapsed hole part of the present invention. DETAILED DESCRIPTION

[0040] 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.

[0041] like Figures 1 to 3 As shown, a construction method for dry rotary drilling of pile foundations in complex geology and hole collapse treatment includes the following steps:

[0042] According to the diameter of the bored pile 100, a cylindrical steel casing 200 of corresponding size is processed, and both ends of the steel casing 200 are open;

[0043] Injecting backfill material 300 into the pile 100 until the backfill material 300 is flush with the bottom of the collapsed hole 101 of the pile 100;

[0044] The steel casing 200 is placed on the upper end of the backfill material 300 in the pile hole 100, and the steel casing 200 and the pile hole 100 are placed coaxially;

[0045] Filling the steel casing 200 with filler 400;

[0046] Pouring concrete 500 into the gap between the outer peripheral wall of the steel casing 200 and the collapsed hole portion 101;

[0047] After the concrete 500 is poured, the steel casing 200 is pulled out from the concrete 500 and the bored pile 100 is ejected;

[0048] After the concrete 500 solidifies, rotary drilling is performed, and the filling material 400 and the backfill material 300 are cleaned and discharged from the pile 100;

[0049] The portion of the bored pile 100 located at the lower end of the collapsed hole portion 101 is backfilled with the backfill material 300, and then the filling material 400 is poured into the steel casing 200, and the concrete 500 is poured into the gap between the outer side of the steel casing 200 and the collapsed hole portion 101. When the concrete 500 is poured, the steel casing 200 is immediately pulled out of the concrete 500, and the steel casing 200 is lifted out of the bored pile 100. When the steel casing 200 is pulled out of the concrete 500, the filling material 400 in the steel casing 200 continues to remain between the concrete 500 to support the concrete 500 on the surrounding side. After the concrete 500 solidifies, the repair process of the collapsed hole portion 101 is completed. After the repair of the collapsed hole portion 101 is completed, rotary drilling is performed to clean and discharge the filling material 400 and the backfill material 300 from the pile 100, so as to facilitate the subsequent reuse of the filling material 400 and the backfill material 300. When the collapsed hole portion 101 is repaired by the present method, the filling material 400 and the backfill material 300 effectively support the concrete 500, thereby preventing the concrete 500 from collapsing and falling, effectively reducing the amount of concrete 500 used in the repair process, and also reducing the waste of concrete 500, and facilitating rotary drilling after the repair is completed.

[0050] Filling the steel casing 200 with filler 400 specifically includes the following steps:

[0051] A guide tube 600 is inserted into the bored pile 100, and the lower end of the guide tube 600 extends into the interior of the steel casing 200;

[0052] The upper end of the conduit 600 extends to the outside of the hole pile 100 and is connected to the hopper 700;

[0053] According to the volume of the steel casing 200, a corresponding volume of filler 400 is poured into the hopper 700;

[0054] The filling material 400 is injected through the conduit 600 and fills the steel casing 200;

[0055] When the filling material 400 is continuously injected into the steel casing 200 through the conduit 600, as the filling material 400 in the steel casing 200 is continuously injected, the lower end of the conduit 600 can be continuously moved upward from the steel casing 200 until the hopper 700 and the filling material 400 in the conduit 600 all fall into the steel casing 200.

[0056] The diameter of the bored pile 100 is greater than the diameter of the outer peripheral wall of the steel casing 200. The difference between the diameter of the bored pile 100 and the diameter of the outer peripheral wall of the steel casing 200 is assumed to be S, and the diameter of the outer peripheral wall of the conduit 600 is assumed to be N, and S≥N.

[0057] Preferably, the length of the steel casing 200 is 3 m, and the difference S between the diameter of the bored pile 100 and the diameter of the outer peripheral wall of the steel casing 200 is 20 cm.

[0058] The material of the backfill material 300 is slag, and the particle size of the slag used near the collapsed hole portion 101 is smaller than the particle size of the slag used near the bottom of the pile 100;

[0059] When the slag particle size used near the lower end of the collapsed hole 101 is small, the leakage of concrete 500 into the backfill layer can be reduced.

[0060] The material of the filler 400 is crushed stone or sand.

[0061] Pouring concrete 500 into the gap between the outer peripheral wall of the steel casing 200 and the collapsed hole portion 101 specifically includes the following steps:

[0062] Insert the lower end of the conduit 600 into the gap between the outer peripheral wall of the steel casing 200 and the collapsed hole 101;

[0063] Measure the height difference L between the upper and lower ends of the collapsed hole 101 by using a measuring rope;

[0064] If the height difference L is less than or equal to the length of the steel casing 200, concrete 500 is poured directly into the gap between the steel casing 200 and the collapsed hole portion 101 through the hopper 700 and the conduit 600 until the upper end surface of the concrete 500 is higher than the upper end of the collapsed hole portion 101;

[0065] If the height difference L is greater than the length of the steel casing 200, the concrete 500 is poured in sections until the upper end surface of the concrete 500 is higher than the upper end of the collapsed hole 101;

[0066] Preferably, as the concrete 500 is continuously injected, the height of the lower end of the conduit 600 can be continuously raised;

[0067] Preferably, when the pouring of the concrete 500 is completed, the upper end surface of the concrete 500 needs to be located 10-20 cm above the upper end of the collapsed hole 101.

[0068] The concrete 500 is poured in sections until the upper end surface of the concrete 500 is higher than the upper end of the collapsed hole 101, which specifically includes the following steps:

[0069] S1. Pour concrete 500 into the gap between the steel casing 200 and the collapsed hole 101 through the hopper 700 and the conduit 600 until the upper end surface of the concrete 500 is lower than or equal to the upper end surface of the steel casing 200;

[0070] S2. Pull the steel casing 200 upward along the axial direction of the steel casing 200, and the upward distance of the steel casing 200 is less than or equal to the length of the steel casing 200;

[0071] S3. Filling the filler 400 into the steel casing 200 through the hopper 700 and the conduit 600 until the filler 400 fills the steel casing 200 again;

[0072] S4. Pour concrete 500 into the gap between the steel casing 200 and the collapsed hole portion 101 through the hopper 700 and the conduit 600 until the upper end surface of the concrete 500 is lower than or equal to the upper end surface of the steel casing 200;

[0073] S5. Repeat steps S2 to S4 until the upper end surface of the concrete 500 exceeds the upper end of the collapsed hole 101.

[0074] The steel casing 200 is provided with a lifting rod, both ends of which are fixed to the upper end of the steel casing 200, so as to facilitate the placement or extraction of the steel casing 200 into or out of the bored pile 100 by a rotary drilling rig or a crane.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0076] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A construction method for dry rotary drilling of pile foundations in complex geology, characterized in that: The following steps are involved: According to the diameter of the bored pile (100), a cylindrical steel casing (200) of corresponding size is processed, and both ends of the steel casing (200) are open; Injecting backfill material (300) into the pile hole (100) until the backfill material (300) is flush with the bottom of the collapsed hole portion (101) of the pile hole (100); Placing the steel casing (200) on the upper end of the backfill material (300) in the bored pile (100), and placing the steel casing (200) and the bored pile (100) coaxially; Filling the steel casing (200) with filler (400); Pouring concrete (500) into the gap between the outer peripheral wall of the steel casing (200) and the collapsed hole portion (101); After the concrete (500) is poured, the steel casing (200) is pulled out from the concrete (500) and the bored pile (100) is removed; After the concrete (500) solidifies, rotary drilling is performed, and the filling material (400) and the backfill material (300) are cleaned out and discharged from the pile hole (100).

2. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 1 is characterized in that: Filling the steel casing (200) with filler (400) specifically includes the following steps: A guide tube (600) is inserted into the bored pile (100), and the lower end of the guide tube (600) extends into the interior of the steel casing (200); The upper end of the conduit (600) extends to the outside of the hole pile (100) and is connected to the hopper (700); According to the volume of the steel casing (200), a corresponding volume of filler (400) is poured into the hopper (700); The filling material (400) is injected through the conduit (600) and fills the steel casing (200).

3. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 2 is characterized in that: The diameter of the bored pile (100) is greater than the diameter of the outer peripheral wall of the steel casing (200). The difference between the diameter of the bored pile (100) and the diameter of the outer peripheral wall of the steel casing (200) is S, and the diameter of the outer peripheral wall of the conduit (600) is N, and S≥N.

4. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 3 is characterized in that: The material of the backfill material (300) is slag, and the particle size of the slag used near the collapsed hole portion (101) is smaller than the particle size of the slag used near the bottom of the pile hole (100).

5. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 4 is characterized in that: The material of the filler (400) is crushed stone or sand.

6. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 5 is characterized in that: Pouring concrete (500) into the gap between the outer peripheral wall of the steel casing (200) and the collapsed hole portion (101) specifically comprises the following steps: Insert the lower end of the conduit (600) into the gap between the outer peripheral wall of the steel casing (200) and the collapsed hole portion (101); Measuring the height difference L between the upper and lower ends of the collapsed hole (101) by means of a measuring rope; If the height difference L is less than or equal to the length of the steel casing (200), concrete (500) is directly poured into the gap between the steel casing (200) and the collapsed hole portion (101) through the hopper (700) and the guide tube (600) until the upper end surface of the concrete (500) is higher than the upper end of the collapsed hole portion (101); If the height difference L is greater than the length of the steel casing (200), the concrete (500) is poured in sections until the upper end surface of the concrete (500) is higher than the upper end of the collapsed hole (101).

7. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 6 is characterized in that: The concrete (500) is poured in sections until the upper end surface of the concrete (500) is higher than the upper end of the collapsed hole (101), which specifically includes the following steps: S1. pouring concrete (500) into the gap between the steel casing (200) and the collapsed hole portion (101) through the hopper (700) and the conduit (600) until the upper end surface of the concrete (500) is lower than or equal to the upper end surface of the steel casing (200); S2. Pull the steel casing (200) upward along the axial direction of the steel casing (200), and the distance of the steel casing (200) moving upward is less than or equal to the length of the steel casing (200); S3. Filling the filling material (400) into the steel casing (200) through the hopper (700) and the conduit (600) until the filling material (400) fills the steel casing (200) again; S4. Pour concrete (500) into the gap between the steel casing (200) and the collapsed hole portion (101) through the hopper (700) and the conduit (600) until the upper end surface of the concrete (500) is lower than or equal to the upper end surface of the steel casing (200); S5. Repeat steps S2 to S4 until the upper end surface of the concrete (500) exceeds the upper end of the collapsed hole (101).

8. The construction method for dry rotary drilling and hole collapse treatment in complex geological pile foundation according to claim 7 is characterized in that: A lifting rod is provided on the steel casing (200), and both ends of the lifting rod are fixed to the upper end of the steel casing (200).

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