Contraction pipe type shear stress coordinated type spiral steel pipe-cement soil combined structure

Abstract

The present application relates to a kind of pipe-reducing shear stress coordination type spiral steel pipe-cement soil combination structure, including pipe-reducing shear stress coordination type spiral steel pipe for implanting in cement soil mixing pile, pipe-reducing shear stress coordination type spiral steel pipe includes steel pipe, the outer side of the steel pipe is sleeved with steel ring cylinder, the outer circumferential surface of the steel ring cylinder is equipped with helical blade extending along the axis direction of steel ring cylinder;The outer circumferential surface of the steel pipe is respectively provided with annular barrier protrusion on the upper and lower sides of steel ring cylinder, and the barrier protrusion is used for limiting steel ring cylinder.This application is simple and reasonable in design, load is transmitted more by the relative sliding between helical blade and steel pipe, greatly relieve the stress concentration problem at the junction of upper helical blade and steel pipe, better comply with the load transmission theory of stiff cement soil composite pile.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of pipe type shear stress coordination type spiral steel pipe-cement soil combined structure. BACKGROUND

[0002] Under the construction requirements of national resource-conserving, environment-friendly society, the low-carbon and sustainable development of engineering field is imperative, and the use of energy-saving, more economical engineering measures and methods is the inevitable choice of development. In the infrastructure of various types of engineering, pile foundation can often provide considerable bearing capacity, but with high cost and huge energy and material consumption, in some engineering construction that only needs small bearing capacity, such as the construction of photovoltaic power station on coastal beach, a large amount of resources is often wasted to meet the minimum requirement of specification. At this time, if the use of reinforced cement composite pile is selected, the cost and energy consumption will be greatly reduced.

[0003] Reinforced cement composite pile is a new type of composite pile in which a reinforced core pile is vertically implanted into a cement soil mixing pile after the construction of the cement soil mixing pile, and the periphery is wrapped by cement soil. It has larger pile side friction of cement soil mixing pile and higher strength and stiffness of core pile.

[0004] In the current reinforced cement composite pile, the reinforced core pile adopts the form of pipe pile, steel pipe, spiral steel pipe, etc. Among them, for the spiral steel pipe used as the inner core, the load borne by the spiral steel pipe is mainly concentrated on the upper spiral blade, and the welding position between the steel pipe and the spiral blade has stress concentration phenomenon, while the lower spiral blade bears too little load. Therefore, it is necessary to improve the above technical problems, and the present case is born accordingly. SUMMARY

[0005] The present application improves the existing problems in the prior art, that is, the technical problem to be solved by the present application is to provide a pipe type shear stress coordination type spiral steel pipe-cement soil combined structure.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is: a pipe type shear stress coordination type spiral steel pipe-cement soil combined structure, which comprises a pipe type shear stress coordination type spiral steel pipe for implanting into a cement soil mixing pile. The pipe type shear stress coordination type spiral steel pipe comprises a steel pipe, a steel ring cylinder is slidably sleeved on the outer side of the steel pipe, and a spiral blade extending along the axis direction of the steel ring cylinder is arranged on the outer circumferential surface of the steel ring cylinder. Ring-shaped barrier protrusions are arranged on the upper and lower sides of the steel ring cylinder on the outer circumferential surface of the steel pipe, and the barrier protrusions are used for limiting the steel ring cylinder.

[0007] Further, the barrier protrusions are coaxially arranged with the steel pipe, and the outer diameter of the barrier protrusions is greater than the outer diameter of the steel ring cylinder.

[0008] Further, the steel ring cylinder is located at the middle of the two side blocking protrusions.

[0009] Further, the steel pipe is of equal cross section; the steel ring cylinder comprises two oppositely arranged half cylinders, the left and right ends of each half cylinder are provided with outwardly extending flange ears, a plurality of vertically spaced connecting bolts are penetrated between the flange ears of the two half cylinders, and the connecting bolts are locked and fixed with nuts to fix the flange ears of the two half cylinders.

[0010] Further, the inner circumferential side of each half cylinder is provided with an inwardly protruding arc arch.

[0011] Further, the minimum distance between the two blocking protrusions is greater than the length of the steel ring cylinder.

[0012] Further, the cross-sectional dimension of the steel pipe uniformly increases from bottom to top; the steel ring cylinder is integrally formed, and the cross-sectional dimension of the steel ring cylinder uniformly increases from bottom to top.

[0013] Further, the steel ring cylinder is a plurality of, and the plurality of steel ring cylinders are spaced apart along the axial direction of the steel pipe; the upper and lower sides of each steel ring cylinder are provided with blocking protrusions.

[0014] Another technical solution adopted by the present application is: a construction method of a shrink pipe type shear stress coordination type spiral steel pipe-cement soil combined structure, comprising the following steps:

[0015] (1) detecting underground obstacles in the application area of the shrink pipe type shear stress coordination type spiral steel pipe-cement soil combined structure, removing the obstacles and backfilling the soil body in time, leveling the site, and layering and ramming;

[0016] (2) excavating the earthwork to the design elevation, measuring and positioning according to the requirements, and making permanent and temporary marks;

[0017] (3) positioning the triaxial mixing pile hole, positioning the pile machine, preparing and injecting the cement slurry according to the requirements, and controlling the sinking and lifting speed of the mixing pile according to the requirements;

[0018] (4) implanting the shrink pipe type shear stress coordination type spiral steel pipe, ensuring the pile position, pile body perpendicularity and elevation.

[0019] Compared with the prior art, the present application has the following effects: the present application is simple and reasonable in design, the load is transmitted more by the relative sliding between the spiral blade and the steel pipe, the stress concentration problem at the connection between the upper spiral blade and the steel pipe is greatly relieved, and the load transmission theory of the reinforced cement soil composite pile is better met. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 is a schematic diagram of the three-dimensional structure of the first embodiment of the present application;

[0021] Fig. 2 is a schematic view of the main cross-sectional structure of embodiment one of the present application;

[0022] Fig. 3 is a schematic view of the three-dimensional structure of the steel pipe in embodiment one of the present application;

[0023] Fig. 4 is a schematic view of the three-dimensional structure of the steel ring cylinder in embodiment one of the present application;

[0024] Fig. 5 is a schematic view of the three-dimensional structure of embodiment two of the present application;

[0025] Fig. 6 is a schematic view of the three-dimensional structure of the steel pipe in embodiment two of the present application;

[0026] Fig. 7 is a schematic view of the three-dimensional structure of the steel ring cylinder in embodiment two of the present application.

[0027] In the drawings:

[0028] 1 - helical blade; 2 - constant-section steel ring cylinder; 3 - constant-section steel pipe; 4 - barrier protrusion; 5 - flange ear; 6 - connecting bolt; 7 - variable-section steel pipe; 8 - variable-section steel ring cylinder; 9 - arc-shaped arch. DETAILED DESCRIPTION

[0029] The present application will be further described in detail below with reference to the drawings and specific embodiments.

[0030] In the description of the present application, it should be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0031] Embodiment one: as Figs. 1-4As shown, the pipe-reducing shear stress coordination type spiral steel pipe-cement soil combined structure of the present application comprises a pipe-reducing shear stress coordination type spiral steel pipe for implanting into a cement soil mixing pile, the pipe-reducing shear stress coordination type spiral steel pipe comprises an equal cross-section steel pipe 3, an equal cross-section steel ring cylinder 2 is sleeved on the outer side of the equal cross-section steel pipe 3 in the vertical direction, and the outer circumferential surface of the equal cross-section steel ring cylinder 2 is provided with spiral blades 1 extending along the axial direction of the equal cross-section steel ring cylinder 2; the outer circumferential surface of the equal cross-section steel pipe 3 is provided with annular barrier protrusions 4 on the upper side and the lower side of the equal cross-section steel ring cylinder 2, respectively, and the barrier protrusions 4 are used for limiting the upward and downward sliding of the equal cross-section steel ring cylinder 2.

[0032] In the embodiment, the barrier protrusions 4 are coaxially arranged with the equal cross-section steel pipe 3, and the outer diameter of the barrier protrusions 4 is greater than the outer diameter of the equal cross-section steel ring cylinder 2.

[0033] In the embodiment, the equal cross-section steel ring cylinder 3 is located in the middle of the barrier protrusions 4 on the upper side and the lower side. By arranging the equal cross-section steel ring cylinder in the middle of the two barrier protrusions, the steel pipe is continuously reduced into the steel ring cylinder, and the compressive bearing capacity can be better provided when the steel pipe is relatively displaced downward, and the anti-pulling bearing capacity can be better provided when the steel pipe is relatively displaced upward.

[0034] In the embodiment, the equal cross-section steel ring cylinder 2 comprises two oppositely arranged half cylinders, the left and right ends of each half cylinder are provided with flange ears 5 extending outward, a plurality of connecting bolts 6 are penetrated between the flange ears of the two half cylinders 5 and are distributed in the vertical direction, and the connecting bolts 6 are locked and fixed with nuts to fix the flange ears of the two half cylinders.

[0035] In the embodiment, the inner circumferential surface of each half cylinder is provided with an arc-shaped arch 9 protruding inward, and the arc-shaped arch 9 is used for embedding into the wall of the equal cross-section steel pipe 3 by a certain depth. During construction, the two half cylinders are butted and sleeved on the outer side of the equal cross-section steel pipe, the arc-shaped arch is used for embedding into the wall of the equal cross-section steel pipe by a certain depth, and then the flange ears of the two half cylinders are locked and fixed with the nuts. During use, when the load value continuously increases, the equal cross-section steel pipe is continuously reduced into the equal cross-section steel ring cylinder, the equal cross-section steel pipe is relatively displaced downward, the load is gradually shared by the lower spiral blades, and so on, the load is gradually transmitted and the stress is redistributed, so as to better realize the purpose of load distribution along the whole length of the pile.

[0036] In the embodiment, the minimum distance between the two barrier protrusions 4 is greater than the length of the equal cross-section steel ring cylinder 2.

[0037] In this embodiment, there are multiple equal-section steel ring cylinders 2, which are spaced apart along the axial direction of the equal-section steel pipe 3; each equal-section steel ring cylinder 2 has a barrier protrusion 4 on its upper and lower sides. Multiple equal-section steel ring cylinders are used in combination to meet the greater shear strength requirements of the inner and outer core interface, and the number of ring-shaped barrier protrusions is set synchronously in proportion to the number of helical blades.

[0038] It should be noted that the steel ring cylinder with uniform cross-section is equipped with a single helical blade on the outside, or it can be composed of multiple helical blades.

[0039] In this embodiment, the uniform cross-section steel pipe is a steel pipe used for construction structures, and a type with a larger wall thickness is adopted.

[0040] Example 2: Figs. 5-7 As shown, the difference between this embodiment and Embodiment 1 lies in the use of a variable cross-section structure for the steel pipe and the steel ring cylinder. Specifically, a variable cross-section steel pipe 7 and a variable cross-section steel ring cylinder 8 are used. Specifically, the variable cross-section steel pipe 7 can be a steel pipe with an inner and outer diameter that increases uniformly from bottom to top, or it can be a solid component with an outer diameter that increases uniformly from bottom to top. The cross-sectional dimensions of the variable cross-section steel ring cylinder 8 increase uniformly from bottom to top.

[0041] In this embodiment, the interior of the variable cross-section steel ring cylinder 8 is no longer equipped with an arc-shaped arch.

[0042] In this embodiment, compared with Embodiment 1, the outer and inner diameters of the variable cross-section steel ring cylinder 8 are scaled up proportionally, the flange ears on both sides are eliminated, and the variable cross-section steel ring cylinder 8 is integrally formed. The assembly sequence is as follows: first, weld the upper annular barrier protrusion of the variable cross-section steel pipe, then pressurize and push the variable cross-section steel ring cylinder to the variable cross-section steel pipe from the lower end of the variable cross-section steel pipe for installation and connection, and finally weld the lower annular barrier protrusion.

[0043] Another technical solution adopted in this invention is: a construction method for a shear stress-coordinated spiral steel pipe-cement-soil composite structure with a reduced-tube design, comprising the following steps:

[0044] (1) Detect underground obstacles in the application area of ​​the shear stress coordinated spiral steel pipe-cement soil composite structure, remove obstacles and backfill soil in a timely manner, level the site, and compact it in layers.

[0045] (2) Excavate the earthwork to the design elevation, measure and set out the location according to the requirements, and make permanent and temporary marks;

[0046] (3) Positioning of the three-axis mixing pile hole, positioning of the pile driver, preparation and injection of cement grout as required, and control of the sinking and lifting speed of the mixing pile as required;

[0047] (4) Insert a shrink-tube shear stress coordinated spiral steel pipe to ensure the pile position, pile verticality and elevation.

[0048] The present application has the advantages that: by changing the stable and unchangeable welding connection between the spiral blade and the steel pipe in the spiral steel pipe-cement soil composite pile into a slidable connection, the load is transmitted into the spiral blade steel cylinder ring through the steel pipe and is transmitted more to the lower spiral blade, the stress is redistributed, the purpose of load distribution along the whole length of the pile is achieved, the stress concentration problem at the connection between the upper spiral blade and the steel pipe is greatly relieved, the load transmission theory of the reinforced cement soil composite pile is better met, the steel pipe continuously enters and shrinks into the steel ring cylinder, the compression bearing capacity is better provided when the relative downward displacement is provided, the uplift bearing capacity is better provided when the relative upward displacement is provided, better bearing performance is achieved, materials are saved, and energy consumption is reduced.

[0049] If the present application discloses or involves mutually fixed and connected parts or structural members, unless otherwise stated, the fixed connection can be understood as: detachable fixed connection (for example, connected by using bolts or screws), and can also be understood as: non-detachable fixed connection (for example, riveting, welding), of course, the mutually fixed connection can also be replaced by an integral structure (for example, integrally formed by using a casting process) (except that the integral forming process is obviously unavailable).

[0050] In addition, the terms used to represent the positional relationship or shape in any of the technical solutions disclosed in the present application include approximate, similar or close states or shapes, unless otherwise stated.

[0051] Any part provided by the present application can be assembled from multiple individual components, or can be an individual component manufactured by an integral forming process.

[0052] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application and not to limit them; although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or some technical features can be replaced by equivalent ones; without departing from the spirit of the technical solutions of the present application, they should be covered in the technical solution range of the present application claimed.

Claims

1. A reduced pipe shear stress accommodating type spiral steel pipe-cement soil composite structure including a reduced pipe shear stress accommodating type spiral steel pipe for implanting into a cement soil mixing pile, the reduced pipe shear stress accommodating type spiral steel pipe including a steel pipe, characterized by: The outer side of the steel pipe is sleeved with a steel ring cylinder, and the outer circumferential surface of the steel ring cylinder is provided with helical blades extending along the axial direction of the steel ring cylinder; the outer circumferential surface of the steel pipe is provided with annular barrier protrusions on the upper and lower sides of the steel ring cylinder, respectively, and the barrier protrusions are used for limiting the steel ring cylinder; The steel pipe is of equal cross section; the steel ring cylinder comprises two oppositely arranged half cylinders, and the left and right ends of each half cylinder are provided with outwardly extending flange ears; a plurality of vertically spaced connecting bolts are penetrated between the flange ears of the two half cylinders, and the connecting bolts are locked and fixed with nuts to lock and fix the flange ears of the two half cylinders. The inner circumferential surface of each half cylinder is provided with an inwardly protruding arc-shaped arch; The steel ring cylinder is a plurality of steel ring cylinders, and the plurality of steel ring cylinders are spaced apart along the axial direction of the steel pipe; the upper and lower sides of each steel ring cylinder are provided with barrier protrusions.

2. The pipe-in-pipe type shear stress coordinating type steel pipe-cement-soil composite structure according to claim 1, characterized by: The barrier protrusions are coaxially arranged with the steel pipe, and the outer diameter of the barrier protrusions is greater than the outer diameter of the steel ring cylinder.

3. The pipe-in-pipe type shear stress coordinating type steel pipe-cement-soil composite structure according to claim 1, characterized by: The steel ring cylinder is located in the middle of the barrier protrusions on the upper and lower sides thereof.

4. The pipe-in-pipe type shear stress coordinating type steel pipe-cement-soil composite structure according to claim 1, characterized by: The distance between the two barrier protrusions is greater than the length of the steel ring cylinder.

5. A construction method of the pipe-in-pipe type shear stress accommodating type helical steel pipe-cement-soil composite structure according to any one of claims 1 to 4, characterized by: The method comprises the following steps: (1) detecting underground obstacles in the application area of the shrink pipe type shear stress coordinated spiral steel pipe-cement soil composite structure, removing the obstacles and backfilling the soil in time, leveling the site, and layering and tamping; (2) excavating the earthwork to the design elevation, measuring and positioning according to the requirements, and making permanent and temporary marks; (3) positioning the triaxial mixing pile hole, positioning the pile machine, preparing and injecting cement slurry according to the requirements, and controlling the sinking and lifting speed of the mixing pile according to the requirements; (4) implanting the shrink pipe type shear stress coordinated spiral steel pipe, and ensuring the pile position, pile body perpendicularity and elevation.

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