Large diameter steel pipe pile and micro pile combined support structure and construction method

Abstract

The present invention discloses a combined support structure of large-diameter steel pipe piles and micro-piles and a construction method, which comprises more than two large-diameter steel pipe piles buried in the foundation at intervals, and I-beams arranged along the axial direction are symmetrically fixed on the outer walls of both sides of each large-diameter steel pipe pile, and the flange at one end of the I-beam is fixedly connected to the outer wall of the large-diameter steel pipe pile; pile holes are respectively opened between two adjacent large-diameter steel pipe piles, and the I-beams on both sides of the large-diameter steel pipe piles are respectively arranged in the pile holes on the corresponding sides, and small-diameter steel pipe piles are also arranged in each pile hole, and the flange at the other end of the I-beam is placed inside the small-diameter steel pipe pile on the corresponding side; concrete is poured in each pile hole. The present invention can increase the overall support capacity and section stiffness of the combined retaining structure.

Description

Technical Field

[0001] The invention relates to the field of supporting structures, and in particular to a supporting structure combined with large-diameter steel pipe piles and micro piles and a construction method. Background Art

[0002] For a long time, the foundation pit support engineering has been mostly in the form of reinforced concrete support and steel structure support, especially reinforced concrete support is widely used. However, with the development of engineering technology, the structure of reinforced concrete support system has shown shortcomings in terms of cost, construction period, environmental protection, etc. Nowadays, PC construction method pile construction technology has become mature and is suitable for support engineering of deep foundation pits in coastal soft soil. This process mainly uses a variety of materials such as steel, steel plate, steel pipe piles, etc. These materials can be combined and spliced ​​arbitrarily to form different forms of retaining piles, and different combinations can be selected according to the actual engineering form. Conventional composite steel piles include composite steel pipe piles, composite U-shaped pipe piles or Larsen steel sheet piles. These composite steel piles are widely used in foundation pit support engineering. However, because the composite steel piles are formed by rigid connection, the connection joint part is prone to joint deformation or even disconnection due to the large force of the overall composite steel pile. Simple steel sheet piles or steel pipe piles, due to their small cross-sectional stiffness, must require multi-layer support and anchor structures when applied in deep foundation pits, which increases the construction difficulty and construction cost, making it difficult to play its advantages of fast and efficient. Therefore, it is necessary to study new combinations that can not only achieve stable joints, but also improve the cross-sectional stiffness of steel pipe piles, reduce support and anchor structures, and reduce construction costs. Summary of the invention

[0003] The object of the present invention is to provide a combined support structure of large-diameter steel pipe piles and micro piles and a construction method thereof, which can increase the overall support capacity and cross-sectional rigidity of the combined support structure.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A combined support structure of large-diameter steel pipe piles and micro piles comprises more than two large-diameter steel pipe piles buried in the foundation at intervals, I-beams arranged along the axial direction are symmetrically fixed on the outer walls of both sides of each large-diameter steel pipe pile, and the flange at one end of the I-beam is fixedly connected to the outer wall of the large-diameter steel pipe pile; pile holes are respectively opened between two adjacent large-diameter steel pipe piles, the I-beams on both sides of the large-diameter steel pipe piles are respectively arranged in the pile holes on the corresponding sides, and a small-diameter steel pipe pile is also arranged in each pile hole, and the flange at the other end of the I-beam is placed inside the small-diameter steel pipe pile on the corresponding side; and concrete is poured into each pile hole.

[0006] The outer diameter of the large-diameter steel pipe pile is greater than 600 mm.

[0007] The inner diameter of the pile hole is 300 mm, and the outer diameter of the small-diameter steel pipe pile is 114-273 mm.

[0008] The I-beam is fixed on the outer wall of the large-diameter steel pipe pile by welding.

[0009] The small-diameter steel pipe pile consists of two symmetrically arranged semicircular pipes.

[0010] The construction method of the large-diameter steel pipe pile and micro-pile combined support structure comprises the following steps:

[0011] 1) Pile holes A and B are drilled at intervals on the foundation, and large-diameter steel pipe piles A with I-beams fixed on both sides are sunk between pile holes A and B. The I-beams on both sides of the large-diameter steel pipe piles A are sunk into pile holes A and B respectively; small-diameter steel pipe piles A are sunk into pile holes A, and then concrete is poured into pile holes A to form micro piles A;

[0012] 2) Drill a pile hole C on one side of the pile hole B, sink a large-diameter steel pipe pile B with I-beams fixed on both sides between the pile holes B and C, sink the I-beams on both sides of the large-diameter steel pipe pile B into the pile hole B and the pile hole C respectively, sink a small-diameter steel pipe pile B into the pile hole B, and then pour concrete into the pile hole B to form a micro pile B;

[0013] 3) Drill a pile hole D on one side of the pile hole C, sink a large-diameter steel pipe pile C with I-beams fixed on both sides between the pile holes C and D, sink the I-beams on both sides of the large-diameter steel pipe pile C into the pile hole C and the pile hole D respectively, sink a small-diameter steel pipe pile C into the pile hole C, and then pour concrete into the pile hole C to form a micro pile C;

[0014] 4) This process is repeated in this way until the last large-diameter steel pipe pile is constructed. A small-diameter steel pipe pile is inserted into the pile hole on the side of the last large-diameter steel pipe pile plate that has not been poured with concrete, and concrete is injected to eventually form a combined support structure of large-diameter steel pipe piles and micro piles.

[0015] The present invention adopts the above technical scheme and has the following beneficial effects: large-diameter steel pipe piles and micro piles are connected by I-beams to realize the combination of steel pipe piles, and micro concrete steel pipe piles are realized by pouring concrete to increase the overall supporting capacity and cross-sectional stiffness of the combined retaining structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments;

[0017] Figure 1 A schematic diagram of a combined support structure of large-diameter steel pipe piles and micro piles according to the present invention;

[0018] Figure 2 It is a schematic diagram of step 1) of the construction method of the present invention;

[0019] Figure 3It is a schematic diagram of step 2) and step 3) of the construction method of the present invention. DETAILED DESCRIPTION

[0020] like Figure 1 As shown, the combined supporting structure of large-diameter steel pipe piles 1 and micro piles of the present invention comprises more than two large-diameter steel pipe piles 1 buried in the foundation at intervals, and I-beams 2 arranged along the axial direction are symmetrically fixed on the outer walls of both sides of each large-diameter steel pipe pile 1, and the flange at one end of the I-beam 2 is fixedly connected to the outer wall of the large-diameter steel pipe pile 1; pile holes 3 are respectively opened between two adjacent large-diameter steel pipe piles 1, and the I-beams 2 on both sides of the large-diameter steel pipe piles 1 are respectively arranged in the pile holes 3 on the corresponding sides, and small-diameter steel pipe piles 4 are also arranged in each pile hole 3, and the flange at the other end of the I-beam 2 is placed inside the small-diameter steel pipe pile 4 on the corresponding side; and concrete 5 is poured into each pile hole 3.

[0021] The outer diameter of the large-diameter steel pipe pile 1 is greater than 600 mm, the inner diameter of the pile hole 3 is 300 mm, and the outer diameter of the small-diameter steel pipe pile 4 is 114-273 mm.

[0022] The I-beam 2 is fixed to the outer wall of the large-diameter steel pipe pile 1 by welding.

[0023] The small-diameter steel pipe pile 4 is composed of two symmetrically arranged semicircular pipes.

[0024] like Figure 2 or Figure 3 As shown, the construction method of the large-diameter steel pipe pile and micro-pile combined support structure of the present invention comprises the following steps:

[0025] 1) Pile holes A and B are drilled at intervals on the foundation, and large-diameter steel pipe piles A with I-beams fixed on both sides are sunk between pile holes A and B. The I-beams on both sides of the large-diameter steel pipe piles A are sunk into pile holes A and B respectively; small-diameter steel pipe piles A are sunk into pile holes A, and then concrete is poured into pile holes A to form micro piles A;

[0026] 2) Drill a pile hole C on one side of the pile hole B, sink a large-diameter steel pipe pile B with I-beams fixed on both sides between the pile holes B and C, sink the I-beams on both sides of the large-diameter steel pipe pile B into the pile hole B and the pile hole C respectively, sink a small-diameter steel pipe pile B into the pile hole B, and then pour concrete into the pile hole B to form a micro pile B;

[0027] 3) Drill a pile hole D on one side of the pile hole C, sink a large-diameter steel pipe pile C with I-beams fixed on both sides between the pile holes C and D, sink the I-beams on both sides of the large-diameter steel pipe pile C into the pile hole C and the pile hole D respectively, sink a small-diameter steel pipe pile C into the pile hole C, and then pour concrete into the pile hole C to form a micro pile C;

[0028] 4) This process is repeated in this way until the last large-diameter steel pipe pile is constructed. A small-diameter steel pipe pile is inserted into the pile hole on the side of the last large-diameter steel pipe pile plate that has not been poured with concrete, and concrete is injected to eventually form a combined support structure of large-diameter steel pipe piles and micro piles.

[0029] The implementation of the present invention is described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes. The above-mentioned specific implementation modes are illustrative rather than limiting the present invention. Those skilled in the art should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. The construction method of the combined support structure of large-diameter steel pipe piles and micro piles is characterized by: The supporting structure includes more than two large-diameter steel pipe piles buried in the foundation at intervals, and I-beams arranged along the axial direction are symmetrically fixed on the outer walls of both sides of the large-diameter steel pipe piles, and the flange at one end of the I-beam is fixedly connected to the outer wall of the large-diameter steel pipe pile; a pile hole is opened between two adjacent large-diameter steel pipe piles, and the I-beams on both sides of the large-diameter steel pipe piles are respectively arranged in the pile holes on the corresponding sides, and a small-diameter steel pipe pile is also arranged in each pile hole, and the flange at the other end of the I-beam is placed inside the small-diameter steel pipe pile on the corresponding side; concrete is poured into each pile hole; The construction method comprises the following steps: 1) Pile holes A and B are drilled at intervals on the foundation, and large-diameter steel pipe piles A with I-beams fixed on both sides are sunk between pile holes A and B. The I-beams on both sides of the large-diameter steel pipe piles A are sunk into pile holes A and B respectively; small-diameter steel pipe piles A are sunk into pile holes A, and then concrete is poured into pile holes A to form micro piles A; 2) Drill a pile hole C on one side of the pile hole B, sink a large-diameter steel pipe pile B with I-beams fixed on both sides between the pile holes B and C, sink the I-beams on both sides of the large-diameter steel pipe pile B into the pile hole B and the pile hole C respectively, sink a small-diameter steel pipe pile B into the pile hole B, and then pour concrete into the pile hole B to form a micro pile B; 3) Drill a pile hole D on one side of the pile hole C, sink a large-diameter steel pipe pile C with I-beams fixed on both sides between the pile holes C and D, sink the I-beams on both sides of the large-diameter steel pipe pile C into the pile hole C and the pile hole D respectively, sink a small-diameter steel pipe pile C into the pile hole C, and then pour concrete into the pile hole C to form a micro pile C; 4) This process is repeated in this way until the last large-diameter steel pipe pile is constructed. A small-diameter steel pipe pile is inserted into the pile hole on the side of the last large-diameter steel pipe pile plate that has not been poured with concrete, and concrete is injected to eventually form a combined support structure of large-diameter steel pipe piles and micro piles.

2. The construction method of the large-diameter steel pipe pile and micropile combined support structure according to claim 1 is characterized in that: The outer diameter of the large-diameter steel pipe pile is greater than 600 mm.

3. The construction method of the large-diameter steel pipe pile and micropile combined support structure according to claim 1 is characterized in that: The inner diameter of the pile hole is 300 mm, and the outer diameter of the small-diameter steel pipe pile is 114-273 mm.

4. The construction method of the large-diameter steel pipe pile and micropile combined support structure according to claim 1 is characterized in that: The I-beam is fixed on the outer wall of the large-diameter steel pipe pile by welding.

5. The construction method of the large-diameter steel pipe pile and micropile combined support structure according to claim 1 is characterized in that: The small-diameter steel pipe pile consists of two symmetrically arranged semicircular pipes.

Images