Stiff composite uplift pile structure

Abstract

The stiff composite uplift pile structure is used as a rear-row pile of a retaining wall, comprises a cement soil pile, and is characterized in that a steel pipe pile is inserted into the cement soil pile, a horizontal circular bottom plate is fixed at the middle upper part of an inner cavity of the steel pipe pile, longitudinal reinforcing steel bars are arranged above the circular bottom plate and are bound together through a plurality of circles of stirrups, and a plurality of reinforcing steel bars are arranged on the circular bottom plate. Core filling concrete is poured in an inner cavity of the steel pipe pile above the circular bottom plate; the upper ends of the steel pipe piles, the core filling concrete and the longitudinal steel bars are all poured in the bearing platform, and studs inserted into the cement soil piles are evenly fixed to the outer walls of the steel pipe piles. According to the stiff composite uplift pile structure, firstly, large frictional resistance generated by the large surface area of the cement soil pile is utilized, and secondly, the steel pipe pile has high tensile capacity, so that the formed stiff composite uplift pile structure integrates the advantages of the cement soil pile and the steel pipe pile, the process is simple, the manufacturing cost is low, and the construction cost is low. The problems that the high filling roadbed is large in protection amount and high in manufacturing cost are well solved.

Description

Technical Field

[0001] The utility model belongs to the field of road subgrade protection, and more specifically, particularly relates to a rigid composite anti-pulling pile structure. Background Art

[0002] With the rapid development of social economy, more and more highways are being built in mountainous and hilly areas. In order to meet the needs of highway lines, more and more high-fill roadbeds are being built. With the increase of extreme weather in my country, road construction has put forward higher requirements for the protection of high-fill roadbeds, especially high-fill retaining walls, which often use pull-out piles for anti-overturning design. Pull-out piles are usually designed with reinforced concrete piles, but the cost is relatively high. Therefore, there is an urgent need for a pull-out pile structure with low cost, good pull-out performance and stable structure. Summary of the invention

[0003] In order to overcome the disadvantages of the above technical problems, the utility model provides a rigid composite anti-pulling pile structure.

[0004] The utility model discloses a rigid composite pull-out resistant pile structure, which is used as a rear-row pile of a retaining wall and comprises a cement soil pile, wherein a cap of the retaining wall is arranged at the upper end of the cement soil pile, and the retaining wall is fixed on the cap. The utility model is characterized in that a steel pipe pile is inserted into the cement soil pile, the steel pipe pile and the cement soil pile are arranged coaxially, a horizontal circular bottom plate is fixed to the middle and upper part of the inner cavity of the steel pipe pile, longitudinal steel bars evenly distributed at intervals in a circular ring are arranged above the circular bottom plate, the longitudinal steel bars are bound together by multiple circles of stirrups, and core-filled concrete is poured in the inner cavity of the steel pipe pile above the circular bottom plate; the upper ends of the steel pipe pile, the core-filled concrete and the longitudinal steel bars are all poured in the cap, and bolts inserted into the cement soil pile are evenly fixed on the outer wall of the steel pipe pile.

[0005] The utility model discloses a rigid composite anti-pulling pile structure, wherein the outer diameter of the cement soil pile is 65 cm to 100 cm, and the 7-day unconfined compressive strength of the cement soil constituting the cement soil pile is not less than 0.8 MPa.

[0006] The utility model discloses a rigid composite pull-out resistant pile structure, wherein the outer diameter of the steel pipe pile is 30 cm to 60 cm, the wall thickness of the steel pipe pile is 8 mm to 10 mm, the lower end of the steel pipe pile is the same length as the cement soil pile, and the length of the steel pipe pile extending into the cap is 5 cm to 10 cm.

[0007] The utility model discloses a rigid composite pull-out resistant pile structure, wherein the bolts on the outer wall of the steel pipe pile are arranged in rows in the vertical and horizontal directions, and the distance between two adjacent rows of bolts in the vertical direction is 35cm-45cm; the diameter of the bolts is 10mm-12mm, and the length is 12cm-15cm.

[0008] The utility model provides a rigid composite pull-out resistant pile structure, wherein the circular bottom plate is made of a circular steel plate, and the circular steel plate is vertically welded to the inner wall of the steel pipe pile; the height of the core-filling concrete is not less than 300 cm, and the core-filling concrete is made of micro-expansive concrete with a grade of 35MPa-45MPa.

[0009] In the rigid composite anti-pulling pile structure of the utility model, the length of the upper end of the longitudinal steel bar extending into the cap is not less than 30 times the diameter of the longitudinal steel bar.

[0010] The utility model discloses a rigid composite anti-pulling pile structure, wherein the steel pipe pile is vibrated and implanted within 6 hours after the cement soil pile is formed, and the axis error between the steel pipe pile and the cement soil pile does not exceed 1 cm.

[0011] The beneficial effects of the utility model are as follows: the rigid composite pull-out resistant pile structure of the utility model has steel pipe piles implanted in the cement soil piles of the rear row piles serving as the retaining wall, the upper ends of the steel pipe piles are provided with longitudinal reinforcement and core-filled concrete, the upper ends of the steel pipe piles, the core-filled concrete and the longitudinal reinforcement are all cast in the cap of the retaining wall, thus realizing a firm connection between the steel pipe piles and the cap; the bolts fixed on the outer wall of the steel pipe piles and extending into the cement soil piles ensure the anchor connection between the steel pipe piles and the cement soil piles, thus, in the rigid composite pull-out resistant pile structure serving as the retaining wall During the service of the rear row piles of the wall, firstly, the greater friction resistance generated by the larger surface area of ​​the cement soil piles is used to resist the uplift force generated when used as the rear row piles, and secondly, the steel pipe piles have a higher tensile capacity, so that the formed rigid composite uplift pile structure combines the advantages of cement soil piles and steel pipe piles, and can resist the uplift force transmitted by the retaining wall when used as the rear row piles. Compared with the existing use of reinforced concrete piles as uplift piles, the process is simple and the cost is low, which better solves the problem of large protection volume and high cost of high fill roadbed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 The utility model is a structural schematic diagram of a rigid composite anti-pulling pile structure applied to a retaining wall.

[0013] In the figure: 1 cement soil pile, 2 steel pipe pile, 3 circular base plate, 4 core filling concrete, 5 longitudinal steel bars, 6 stirrups, 7 studs, 8 front row piles, 9 rear row piles, 10 cap, 11 retaining wall. DETAILED DESCRIPTION

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0015] like Figure 1As shown, a structural schematic diagram of the rigid composite pull-out pile structure of the utility model applied to a retaining wall is given, in which the rigid composite pull-out pile is used as the rear row pile 9 of the retaining wall, and the retaining wall also includes a front row pile 8, a cap 10 and a retaining wall 11, the front row pile 8 is located on the outside, and the rear row pile 9 is located on the inside, the front row pile 8 and the rear row pile 9 are both arranged in a plurality of intervals, the cap 10 is fixed to the upper ends of the front row pile 8 and the rear row pile 9, and the retaining wall 11 is fixed on the cap 10. The rear facade of the retaining wall 11 (i.e., the surface facing the rear row of piles 9) is the retaining surface. The force direction of the retaining wall 11 is shown by the arrow direction in the figure, that is, the rear facade of the retaining wall 11 is subjected to an outward thrust, which is transmitted through the pedestal 10 to the front row of piles 8 under compression and the rear row of piles 9 under tension. Therefore, the front row of piles 8 can be ordinary precast concrete piles, while the rear row of piles 9 need to be pull-out piles. For this reason, the utility model provides a rigid composite pull-out pile structure for use as the rear row of piles 9 of the retaining wall.

[0016] The rigid composite anti-pulling pile structure shown is composed of a cement soil pile 1 and a steel pipe pile 2. The cement soil pile 1 is formed by mixing a curing agent with soil. The curing agent is usually a mixture of cement and fly ash. The cement soil pile 1 adopts a three-tube high-pressure rotary jet pile construction process, and cement slurry, water and high-pressure air mixed with cement and fly ash are driven into the ground by a rotary jet drill. The steel pipe pile 2 is implanted in the cement soil pile 1. The steel pipe pile 2 is implanted by vibration within 6 hours after the cement soil pile 1 is formed. Under normal circumstances, the steel pipe pile 2 is required to be coaxial with the cement soil pile 1. Even if there is a deviation, the error between the axis of the steel pipe pile 2 and the axis of the cement soil pile 1 is required to be no more than 1 cm.

[0017] A horizontal circular bottom plate 3 is fixed in the middle and upper part of the inner cavity of the steel pipe pile 2 shown. Longitudinal steel bars 5 spaced apart in a circular column are arranged above the circular bottom plate 3. The longitudinal steel bars 5 are bound together by multiple circles of stirrups 6 spaced apart along the longitudinal direction. After the longitudinal steel bars 5 and stirrups 6 are arranged above the circular bottom plate 3, core-filling concrete 4 is poured in the inner cavity of the steel pipe pile 2 above the circular bottom plate 3. The core-filling concrete 4 usually adopts micro-expansive concrete. After the core-filling concrete 4 solidifies, a firm connection between the longitudinal steel bars 5, the core-filling concrete 4 and the steel pipe pile 2 is achieved.

[0018] The upper ends of the steel pipe pile 2, the core concrete 4 and the longitudinal reinforcement 5 are all cast in the cap 10, so that the cap 10 and the steel pipe pile 2 are firmly connected. The outer wall of the steel pipe pile 2 is evenly welded with studs 7, which extend into the cement soil pile 1. After the cement soil of the cement soil pile 1 solidifies, the outer wall of the steel pipe pile 2 and the studs 7 are in close contact with the cement soil pile 1, so as to ensure the stable anchoring between the steel pipe pile 2 and the cement soil pile 1.

[0019] It can be seen that in the rigid composite pull-out pile structure of the utility model, the steel pipe pile 2 is anchored with the cement soil pile 1 by bolts 7, and the steel pipe pile 2 is firmly connected with the cap 10 by pouring its upper end, core-filled concrete 4 and longitudinal steel bars 5 in the cap 10. In this way, when the retaining wall 11 is subjected to the external thrust and forms the pull-out force on the steel pipe pile 2 through the transfer of the cap 10, the large friction resistance generated by the large surface area around the cement soil pile 1 and the surrounding soil, and the high tensile strength of the steel pipe pile 2, make the rigid composite pull-out pile structure of the utility model can withstand the large pull-out force, and can be used as the rear pile 9 of the retaining wall. Compared with the existing use of reinforced concrete piles as pull-out piles, the process is simple and the cost is low, which better solves the problem of large protection amount and high cost of high fill roadbed.

[0020] As a specific requirement, the outer diameter of the cement soil pile 1 is 65 cm to 100 cm, and the 7-day unconfined compressive strength of the cement soil constituting the cement soil pile 1 is not less than 0.8 MPa. The outer diameter of the steel pipe pile 2 is 30 cm to 60 cm, the wall thickness of the steel pipe pile 2 is 8 mm to 10 mm, the lower end of the steel pipe pile 2 is the same length as the cement soil pile 1, and the length of the steel pipe pile extending into the cap 10 is 5 cm to 10 cm.

[0021] The bolts 7 on the outer wall of the steel pipe pile 2 are arranged in rows in the vertical and horizontal directions, and the distance between two adjacent rows of bolts in the vertical direction is 35cm~45cm; the diameter of the bolt 7 is 10mm~12mm, and the length is 12cm~15cm. The circular bottom plate 3 is made of a round steel plate, which is vertically welded to the inner wall of the steel pipe pile 2; the height of the core filling concrete 4 is not less than 300cm, and the core filling concrete 4 is a micro-expansive concrete with a grade of 35MPa~45MPa. The length of the upper end of the longitudinal steel bar 5 extending into the cap 10 is not less than 30 times the diameter of the longitudinal steel bar 5.

Claims

1. A rigid composite anti-pulling pile structure, used as a rear row pile (9) of a retaining wall, comprising a cement soil pile (1), a retaining wall cap (10) being arranged at the upper end of the cement soil pile, and a retaining wall (11) being fixed on the cap; characterized in that: A steel pipe pile (2) is inserted into the cement soil pile. The steel pipe pile and the cement soil pile are arranged coaxially. A horizontal circular bottom plate (3) is fixed to the middle and upper part of the inner cavity of the steel pipe pile. Longitudinal steel bars (5) are evenly distributed in a circular ring shape above the circular bottom plate. The longitudinal steel bars are tied together by multiple circles of stirrups (6). Core-filling concrete (4) is poured into the inner cavity of the steel pipe pile above the circular bottom plate. The upper ends of the steel pipe pile, the core-filling concrete and the longitudinal steel bars are all poured into the cap. Bolts (7) inserted into the cement soil pile are evenly fixed on the outer wall of the steel pipe pile.

2. The rigid composite anti-pulling pile structure according to claim 1 is characterized in that: The outer diameter of the cement soil pile (1) is 65 cm to 100 cm, and the 7-day unconfined compressive strength of the cement soil constituting the cement soil pile is not less than 0.8 MPa.

3. The rigid composite anti-pulling pile structure according to claim 1 or 2, characterized in that: The outer diameter of the steel pipe pile (2) is 30 cm to 60 cm, the wall thickness of the steel pipe pile is 8 mm to 10 mm, the lower end of the steel pipe pile is the same length as the cement soil pile (1), and the length of the steel pipe pile extending into the cap (10) is 5 cm to 10 cm.

4. The rigid composite anti-pulling pile structure according to claim 1 or 2, characterized in that: The studs (7) on the outer wall of the steel pipe pile (2) are arranged in rows in both the vertical and horizontal directions, and the distance between two adjacent rows of studs in the vertical direction is 35 cm to 45 cm; the diameter of the studs is 10 mm to 12 mm, and the length is 12 cm to 15 cm.

5. The rigid composite anti-pulling pile structure according to claim 1 or 2, characterized in that: The circular bottom plate (3) is made of a circular steel plate, which is vertically welded to the inner wall of the steel pipe pile (2); the height of the core-filling concrete (4) is not less than 300 cm, and the core-filling concrete is micro-expansive concrete with a grade of 35 MPa to 45 MPa.

6. The rigid composite anti-pulling pile structure according to claim 1 or 2, characterized in that: The length of the upper end of the longitudinal steel bar (5) extending into the cap (10) is not less than 30 times the diameter of the longitudinal steel bar.

7. The rigid composite anti-pulling pile structure according to claim 1 or 2, characterized in that: The steel pipe pile (2) is vibrated and implanted within 6 hours after the cement soil pile (1) is formed, and the axis error between the steel pipe pile and the cement soil pile does not exceed 1 cm.

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