Prestressed pipe pile composite foundation

Abstract

The invention belongs to the civil construction technology, and relates to a prestressed pipe pile composite foundation which comprises pipe piles (1) arranged at intervals and inter-pile soil layers (2) located between the adjacent pipe piles (1), and cemented soil supporting layers (3) are arranged on the inter-pile soil layers (2) and the pipe piles (1) on the two sides of the inter-pile soil layers (2). The cement soil supporting layer (3) sequentially comprises a fiber reinforced cement soil layer (31), a gravel and cement soil mixed layer (32) and a gravel drainage layer (33) from top to bottom. The prestressed pipe pile composite foundation has the advantages that the stress ratio of the pipe piles to soil between the piles is large, and the cost is low.

Description

Technical Field

[0001] The present invention belongs to the technical field of civil engineering construction, and relates to a prestressed pipe pile composite foundation. Background Art

[0002] In current construction operations, after prestressed pipe piles are driven into the ground, according to construction standards, the stress between the pipe piles and the soil between the piles should be within the standard range to ensure that the supporting force of the pipe piles can be fully utilized. In current construction operations, a layer of crushed stones is laid on the surface between the pipe piles. Although the voids between the crushed stones can displace within a certain range and can adapt to the minor deformation of the foundation, this method will disperse the load stress, thereby reducing the stress ratio between the pipe piles and the soil between the piles, that is, weakening the supporting effect of the pipe piles. On the other hand, the cost of using a large amount of crushed stones is relatively high. Summary of the Invention

[0003] The purpose of the present invention is to solve the above problems and provide a prestressed pipe pile composite foundation.

[0004] To achieve the above purpose, the present invention provides a prestressed pipe pile composite foundation, which includes spaced pipe piles and a soil layer between adjacent pipe piles. A cement soil support layer is provided on the soil layer between the piles and on the two sides of the pipe piles. The cement soil support layer successively includes a fiber-reinforced cement soil layer, a crushed stone-cement soil mixed layer, and a crushed stone drainage layer from top to bottom.

[0005] Further, an inverted conical structure is provided at the upper end of the pipe pile, and a plurality of steel bars are spaced on the outer periphery of the inverted conical structure.

[0006] Further, the crushed stone drainage layer is located on the soil layer between the piles, the crushed stone-cement soil mixed layer is located on the crushed stone drainage layer and the inverted conical structure, and the fiber-reinforced cement soil layer is located on the crushed stone-cement soil mixed layer.

[0007] Further, the steel bars extend into the crushed stone drainage layer and the crushed stone-cement soil mixed layer.

[0008] Further, a geogrid is provided between the crushed stone drainage layer and the crushed stone-cement soil mixed layer, and between the crushed stone-cement soil mixed layer and the fiber-reinforced cement soil layer.

[0009] Further, the cement content of the fiber-reinforced cement soil layer is 6%, and the polypropylene fiber is 0.8 kg / m 3 .

[0010] Further, the volume ratio of crushed stones to cement soil in the crushed stone-cement soil mixed layer is 4:6, the cement content in the cement soil is 4%, and the particle size of the crushed stones is 10-20 mm.

[0011] Further, the gravel particle size of the gravel drainage layer is 20-30 mm.

[0012] The beneficial effects of the present invention are as follows:

[0013] For the pre-stressed pipe pile composite foundation of the present invention, the inverted conical structure, the radially arranged steel bar claws and the layered cement soil support layer are adopted, which can realize the smooth transfer of rigidity to flexibility from top to bottom, effectively improve the stress ratio between the pipe piles and the soil layer between the piles, enhance the support effect of the pipe piles, and at the same time solve the problems of interval water permeability and support of small deformations.

[0014] For the pre-stressed pipe pile composite foundation of the present invention, the application of a large amount of gravel is replaced by cement soil, which can significantly reduce the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematically showing the structural diagram of a pre-stressed pipe pile composite foundation according to an embodiment of the present invention.

[0016] The meanings represented by the reference numerals in the drawings are as follows:

[0017] 1, pipe pile; 2, soil layer between piles; 3, cement soil support layer; 31, fiber-reinforced cement soil layer; 32, gravel-cement soil mixed layer; 33, gravel drainage layer; 11, inverted conical structure; 12, steel bar claws; 4, geogrid. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] The present invention will be described in detail below with reference to the drawings and specific embodiments. The embodiments cannot be enumerated one by one here, but the embodiments of the present invention are not limited to the following embodiments.

[0020] As Figure 1 shown, the present invention provides a pre-stressed pipe pile composite foundation, including spaced pipe piles 1 and the soil layer 2 between adjacent pipe piles 1. A cement soil support layer 3 is provided on the soil layer 2 between the piles and on both sides of the pipe piles 1. The cement soil support layer 3 includes a fiber-reinforced cement soil layer 31, a gravel-cement soil mixed layer 32 and a gravel drainage layer 33 in sequence from top to bottom.

[0021] Specifically, the upper end of the pipe pile 1 is provided with an inverted conical structure 11. A plurality of steel bar claws 12 are arranged at intervals on the outer periphery of the inverted conical structure 11. The gravel drainage layer 33 is located on the inter-pile soil layer 2. The gravel-cement-soil mixed layer 32 is located on the gravel drainage layer 33 and the inverted conical structure 11. The fiber-reinforced cement soil layer 31 is located on the gravel-cement-soil mixed layer 32. The steel bar claws 12 extend into the gravel drainage layer 33 and the gravel-cement-soil mixed layer 32. A geogrid 4 is provided between the gravel drainage layer 33 and the gravel-cement-soil mixed layer 32, and between the gravel-cement-soil mixed layer 32 and the fiber-reinforced cement soil layer 31.

[0022] In the specific construction process of the prestressed pipe pile composite foundation of the present invention, the pipe pile 1 can be driven into the inter-pile soil layer 2 so that the inverted conical structure 11 is located above the inter-pile soil layer 2, and then the gravel drainage layer 33, the geogrid 4, the gravel-cement-soil mixed layer 33, the geogrid 4 and the fiber-reinforced cement soil layer 31 are laid in sequence. Among them, the cement content of the fiber-reinforced cement soil layer 31 is 6%, and the polypropylene fiber is 0.8 kg / m 3 . In the gravel-cement-soil mixed layer 32, the volume ratio of gravel to cement soil is 4:6. The cement content in the cement soil is 4%. The particle size of the gravel is 10-20 mm, and the particle size of the gravel in the gravel drainage layer 33 is 20-30 mm.

[0023] The comparison between the prestressed pipe pile composite foundation of the present invention and the traditional gravel cushion through experiments is as follows:

[0024]

[0025] The prestressed pipe pile composite foundation of the present invention adopts the settings of the inverted conical structure 11, the radial steel bar claws and the layered cement soil support layer 3, which can realize the smooth transfer of rigidity to flexibility from top to bottom, can effectively increase the stress ratio between the pipe pile 1 and the inter-pile soil layer 2, improve the support effect of the pipe pile 1, and at the same time solve the problems of interval water permeability and support of small deformations.

[0026] The above is only one embodiment of the present invention and is not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A prestressed pipe pile composite foundation, characterized in that: The invention comprises pipe piles (1) arranged at intervals and an inter-pile soil layer (2) located between adjacent pipe piles (1); a cement soil support layer (3) is provided on the inter-pile soil layer (2) and the pipe piles (1) on both sides thereof; the cement soil support layer (3) comprises, from top to bottom, a fiber-reinforced cement soil layer (31), a crushed stone cement soil mixed layer (32) and a crushed stone drainage layer (33).

2. The prestressed pipe pile composite foundation according to claim 1, characterized in that: An inverted cone structure (11) is provided at the upper end of the pipe pile (1), and a plurality of steel bar claws (12) are provided at intervals on the outer periphery of the inverted cone structure (11).

3. The prestressed pipe pile composite foundation according to claim 2, characterized in that: The crushed stone drainage layer (33) is located on the inter-pile soil layer (2), the crushed stone cement soil mixed layer (32) is located on the crushed stone drainage layer (33) and the inverted cone structure (11), and the fiber-reinforced cement soil layer (31) is located on the crushed stone cement soil mixed layer (32).

4. The prestressed pipe pile composite foundation according to claim 3, characterized in that: The steel bar claws (12) extend into the gravel drainage layer (33) and the gravel cement soil mixed layer (32).

5. The prestressed pipe pile composite foundation according to claim 4, characterized in that: A geogrid (4) is provided between the crushed stone drainage layer (33) and the crushed stone cement soil mixed layer (32), and between the crushed stone cement soil mixed layer (32) and the fiber-reinforced cement soil layer (31).

6. The prestressed pipe pile composite foundation according to claim 5, characterized in that: The fiber reinforced cement soil layer (31) has a cement content of 6% and polypropylene fibers of 0.8 kg / m 3 .

7. The prestressed pipe pile composite foundation according to claim 6, characterized in that: The volume ratio of crushed stone to cement soil in the crushed stone cement soil mixed layer (32) is 4:6, the cement content in the cement soil is 4%, and the crushed stone particle size is 10-20 mm.

8. The prestressed pipe pile composite foundation according to claim 7, characterized in that: The crushed stone drainage layer (33) has a particle size of 20-30 mm.

Images