Flexible-rigid composite pile and construction method thereof

Abstract

The invention discloses a flexible-rigid composite pile and a construction method thereof. The flexible-rigid composite pile comprises a rigid pile provided with a core pile and a cement soil bulk pile, the rigid pile is configured to be a prefabricated concrete pipe pile, and the concrete pipe pile is provided with a pile body with blades and a conical pile head; and the cement soil bulk piles are configured to be formed by grouting construction along with the rotary excavating vibration pile forming process of the rigid piles. The bearing capacity can be improved, the construction cost can be reduced, the construction period can be shortened, and the construction efficiency and quality are improved.

Description

Technical Field

[0001] The invention relates to a rigid composite pile, in particular to a flexible-rigid composite pile and a construction method thereof, belonging to the technical field of pile foundation construction. Background Art

[0002] As is known, pile foundation is a foundation form with high bearing capacity, wide application range and long history. When the bearing capacity of shallow foundation cannot meet the design requirements of superstructure load, pile foundation can be used to transfer and absorb the load to deeper soil layer. Pile foundation has been widely used in industrial and civil construction, ports, highways, power, railway bridges and other projects.

[0003] Traditional pile foundations are mainly divided into two categories: cast-in-place pile foundations and direct hammer / static pressure precast pile foundations. Cast-in-place piles are not restricted by stratum changes, do not require pile connection and cutting, have strong adaptability, and have neither the negative effect of soil squeezing nor the ability to pass through various hard interlayers, embedded rocks, and enter various hard bearing layers. However, their shortcomings are that cast-in-place piles have slow efficiency, high cost, difficult quality control, and are not environmentally friendly. Precast piles are prefabricated in factories and have the advantages of high strength, reliable quality, fast construction efficiency, low cost, energy saving and environmental protection. Their shortcomings are that precast piles directly driven / pressed into the factory are only suitable for soft soil areas, and the soil squeezing effect produced in some soft soil areas is more obvious, and the scope of application of the soil layer is relatively limited.

[0004] As a new type of combined pile foundation, composite piles combine the outer core solidified soil piles and the inner core precast piles. They fully utilize the larger contact area of ​​the outer core solidified soil piles to provide lateral friction resistance, while giving full play to the higher strength precast core piles to bear vertical loads, improving the load transfer path and depth of the pile foundation, and giving full play to the advantages of the two materials. They are not only reliable in quality, simple in construction, and low in cost, but also greatly improve the state of the soil between piles, and the bearing capacity of a single pile is higher. At the same time, they greatly broaden the application scope of single pile methods and processes, and have good economic and social benefits.

[0005] At present, common methods of composite pile construction include the central excavation and bottom expansion method and the rotary drilling and pile planting method. The central excavation and bottom expansion method is a method of first constructing a loose pile and then expanding the bottom at the pile end. The rotary drilling and pile planting method is a method of pre-drilling a hole to the designed elevation using a rotary drilling device, injecting cement soil, concrete or other pile-fixing liquid into the hole, and then using a pile driving device to press the prefabricated pile into the hole.

[0006] Both of the above methods require the construction of loose piles first and then rigid piles. During this period, rigid pile construction has the problem of pile sinking difficulties, and loose pile construction has the problem of hole collapse when encountering silt, which leads to reduced construction efficiency, extended construction period, increased project cost, and is not conducive to ensuring the good bearing capacity of composite piles.

[0007] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0008] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention proposes a flexible-rigid composite pile and a construction method thereof, which can not only improve the bearing capacity and reduce the construction cost, but also shorten the construction period and improve the construction efficiency and quality.

[0009] A flexible-rigid composite pile according to the present invention comprises:

[0010] A rigid pile with a core pile, the rigid pile is configured as a prefabricated concrete pipe pile, the concrete pipe pile has a pile body with blades and a conical pile head;

[0011] Cement-soil bulk piles are configured to be constructed by grouting simultaneously with the rotary drilling and vibration pile-forming process of rigid piles.

[0012] According to one embodiment of the present invention, the blades of the bladed pile shaft are configured as single spiral blades integrally connected to the outer surface of the pile shaft.

[0013] According to one embodiment of the present invention, the single spiral blade is integrally arranged at one end close to the cone pile head.

[0014] According to one embodiment of the present invention, the core pile is configured as a cast-in-place reinforced concrete structure, which is formed inside the top end of the concrete pipe pile. The binding steel bars of the reinforced concrete structure have connecting steel bars extending above the ground, and the connecting steel bars are used to connect the base structure.

[0015] According to one embodiment of the present invention, the shape of the connecting steel bar is configured as a cone, and the connecting steel bar is butted against the binding steel bars of the reinforced concrete structure through the small end of the cone.

[0016] According to one embodiment of the present invention, the rigid piles and the cement-soil bulk piles adopt an equal core structure.

[0017] According to the present invention, a construction method of the above-mentioned flexible-rigid composite pile comprises the following steps:

[0018] Make rigid piles without core piles;

[0019] Construct rigid piles on the ground at predetermined pile locations;

[0020] During the pile sinking process, soil is taken and grouting is performed simultaneously to construct cement-soil bulk piles;

[0021] Sink the rigid pile to the designed elevation before the cement-soil bulk pile begins to set;

[0022] By tying steel bars and pouring concrete, the support plate and core pile are constructed inside the rigid pile;

[0023] The construction is completed after the cement soil on the sides and bottom of the rigid pile is solidified.

[0024] According to one embodiment of the present invention, making a rigid pile without a core pile specifically includes:

[0025] A steel cage in the form of a tube is processed, and a conical pile head and blades are welded to the end and outer wall thereof respectively, and concrete is poured until the steel cage is formed into a pile body with blades.

[0026] According to one embodiment of the present invention, constructing a rigid pile on the ground at a predetermined pile position specifically includes:

[0027] During construction, rotary drilling and vibration are used to form piles, and the pile body with blades is used to take soil.

[0028] According to one embodiment of the present invention, during the pile sinking process, soil is taken and grouting is performed to construct cement-soil bulk piles, which specifically includes:

[0029] After the bladed pile body of the rigid pile enters a predetermined depth below the ground, grouting is injected into the surrounding soil of the bladed pile body below the ground.

[0030] According to the flexible-rigid composite pile and the construction method thereof of the present invention, a new pile type consisting of a core pile, a rigid pile and a cement-soil bulk pile can be utilized, which can improve the bearing capacity while reducing the construction cost. In particular, the rigid pile is innovatively constructed first, and then the bulk pile is cast during the pile sinking process, thereby achieving the purpose of shortening the construction period and improving the construction efficiency and quality.

[0031] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0033] Figure 1 Schematic diagram of the structure of some embodiments of the flexible-rigid composite pile of the present invention.

[0034] Figures 2 to 5 It is a schematic structural diagram of some embodiments of the flexible-rigid composite piles of the present invention during the construction process.

[0035] Figure 6 Schematic diagram of the process of some embodiments of the construction method of the flexible-rigid composite pile of the present invention.

[0036] Meaning of reference numerals in the figure:

[0037] 100-rigid pile;

[0038] 101-pile with blades; 1011-single spiral blade;

[0039] 102-conical pile head;

[0040] 103-core pile;

[0041] 1031-Reinforced concrete structure; 1031-1-Binding of steel bars;

[0042] 1032-Connecting steel bars;

[0043] 200-cement soil bulk pile. DETAILED DESCRIPTION

[0044] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0045] In the related art, composite piles constructed by conventional mid-excavation and bottom expansion methods and rotary drilling and piling methods, as well as some known composite piles, such as CN115807427A (cement soil steel spiral composite piles and their construction methods) and CN117488777A (spiral rigid composite piles, their construction methods and construction pile drivers), all require the construction of loose piles first and then rigid piles. Obviously, this has become a common, long-term and consistent practice in the industry. Therefore, there are problems such as difficulty in sinking rigid piles, easy collapse of loose piles when encountering silt, reduced construction efficiency, extended construction period, increased project cost and impact on bearing capacity.

[0046] In view of this, the embodiments of the present invention application aim to provide a flexible-rigid composite pile and a construction method thereof. By arranging a rigid pile with a core pile and a cement-soil bulk pile, the respective advantages of the bulk pile and the rigid pile can be fully utilized to improve the bearing capacity. In addition, during the rotary drilling and forming process of the rigid pile, the cement-soil bulk pile is subsequently constructed by grouting. The construction is completed before the bulk pile solidifies. This not only makes it easier to penetrate the sand layer and form a pile, but also has no window period, fast construction and a short cycle, which can significantly reduce the project cost and greatly shorten the construction period, thereby solving the above-mentioned problems.

[0047] According to the following Figure 1-Figure 6 The invention provides a detailed description of the quick-change mechanism of the ceiling light for the vacuum forming mould of the refrigerator refrigeration liner.

[0048] like Figure 1As shown, an embodiment of the present invention provides a flexible-rigid composite pile, including a rigid pile 100 provided with a core pile 103 and a cement-soil bulk pile 200. The rigid pile 100 is configured as a prefabricated concrete pipe pile, and the concrete pipe pile has a pile body 101 with blades and a conical pile head 102; the cement-soil bulk pile 200 is configured to be grouting-constructed simultaneously with the rotary drilling and vibration pile-forming process of the rigid pile 100.

[0049] In some implementations of the flexible-rigid composite pile embodiment of the present invention, the blades of the bladed pile body 101 are configured as single spiral blades 1011 integrally connected to the outer surface of the pile body.

[0050] When in use, the concrete pipe pile acts on the ground at a predetermined pile position with the help of the conical pile head 102, and then the rotating single spiral blade 1011 is used to continuously sink the pile and take soil. While sinking the pile and taking soil, a certain gap is formed on the side of the concrete pipe pile for grouting construction of cement soil bulk pile 200.

[0051] In some implementations of the flexible-rigid composite pile embodiment of the present invention, the single spiral blade 1011 is integrally arranged at one end close to the conical pile head 102 .

[0052] Reference Figure 2-5 The single spiral blades 1011 are concentrated at the lower end of the concrete pipe pile, which is close to the cone pile head 102, so that the bladed pile body 101 follows the cone pile head 102 to sink the pile more smoothly, quickly and directionally. There is a section at the upper end of the concrete pipe pile where the single spiral blades 1011 are not set. This section increases the cement soil loose pile body at the end, which is conducive to optimizing the more complete and reliable integration with the rigid pile 100.

[0053] In some embodiments of the flexible-rigid composite pile embodiment of the present invention, the core pile 103 is configured as a cast-in-place reinforced concrete structure 1031, which is formed inside the top of the concrete pipe pile. The binding steel bars 1031-1 of the reinforced concrete structure 1031 have connecting steel bars 1032 extending above the ground, and the connecting steel bars 1032 are used to connect the base structure.

[0054] In some implementations of the flexible-rigid composite pile embodiment of the present invention, the connecting steel bar 1032 is configured as a cone, and the connecting steel bar 1032 is connected to the binding steel bar 1031 - 1 of the reinforced concrete structure 1031 through the small end of the cone.

[0055] Reference Figure 1The binding steel bars 1031-1 and the connecting steel bars 1032 can be a steel cage that is connected together or formed in one piece. The lower end of the column of the steel cage serves as the binding steel bars 1031-1, which is arranged inside the top of the concrete pipe pile and cast to form a reinforced concrete structure 1031. The lower end of the cone of the steel cage serves as the connecting steel bars 1032, which is cast on the ground to form a foundation structure.

[0056] In some implementations of the embodiments of the present invention, the rigid pile 100 and the cement-soil bulk pile 200 adopt an equal core structure. Exemplarily, in this implementation, the rigid pile 100 and the cement-soil bulk pile 200 have the same pile bottom elevation.

[0057] like Figure 2-6 As shown, an embodiment of the present invention provides a construction method of the above-mentioned flexible-rigid composite pile, comprising the following steps:

[0058] S100, manufacturing a rigid pile 100 without a core pile 103;

[0059] More specifically, the rigid pile 100 without the core pile 103 is produced in a prestressed manner in a factory.

[0060] S200, constructing a rigid pile 100 on the ground at a predetermined pile position;

[0061] More specifically, a control network is established, pile positions are measured and placed, pile position alignment is reviewed, and the rigid piles 100 are constructed on the ground at predetermined pile positions.

[0062] S300, taking soil and grouting at the same time during the pile sinking process, constructing cement soil bulk pile 200;

[0063] More specifically, a vibrating long spiral drill is used to construct the pile foundation, and a vibration pile-making method is adopted. A vibrating hammer is started at the top of the pile, and the pile sinks under the action of vibration. During the pile sinking process, soil is taken and grouting is performed simultaneously. During the grouting process, the bearing layer is stirred so that the sand and gravel of the bearing layer are fully mixed. 200 cement-soil bulk piles are constructed, and construction errors are well controlled.

[0064] S400, sinking the rigid pile 100 to the designed elevation before the cement-soil bulk pile 200 begins to set;

[0065] More specifically, each pile foundation is constructed at one time, and the rigid pile 100 is sunk to the designed elevation before the cement soil bulk pile 200 begins to set.

[0066] S500, by tying the steel bars 1031-1 and pouring concrete, a support plate and a core pile 103 are constructed inside the rigid pile 100;

[0067] As is known, a support plate is arranged at the lower part of the steel cage to prevent concrete from falling.

[0068] S600: After the cement soil on the side and bottom of the rigid pile 100 is solidified, the construction is completed.

[0069] In some implementations of the construction method of the present invention, manufacturing a rigid pile 100 without a core pile 103 specifically includes:

[0070] A steel cage in the form of a tube is processed, and a conical pile head 102 and blades are welded to the end and outer wall thereof respectively, and concrete is poured until the steel cage is formed into a pile body 101 with blades.

[0071] In some implementations of the construction method of the present invention, constructing a rigid pile 100 on the ground at a predetermined pile position specifically includes:

[0072] During construction, rotary drilling and vibration are used to form piles, and the pile body 101 with blades is used to take soil.

[0073] In some implementations of the construction method of the present invention, soil is taken and grouting is performed during the pile sinking process to construct the cement soil bulk pile 200, which specifically includes:

[0074] After the bladed pile body 101 of the rigid pile 100 enters a predetermined depth below the ground, grouting is injected into the surrounding soil of the bladed pile body 101 below the ground.

[0075] The load transfer path of the flexible-rigid composite pile provided by the embodiment of the present invention is: the upper load is transferred from the pile top to the bulk pile side and the bottom of the rigid pile 100, taking advantage of the respective end resistance and side resistance, thereby effectively improving the bearing capacity of the composite pile and reducing the settlement of the pile. The construction method of the flexible-rigid composite pile provided by the embodiment of the present invention greatly improves the construction efficiency by grouting the cement-soil bulk pile 200 while the rigid pile 100 is being drilled and bored, and has the advantages of small construction disturbance, fast construction speed, and low cost.

[0076] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0077] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0078] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0079] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Any simple modifications and equivalent changes made to the above embodiments based on the technical essence of the present invention fall within the protection scope of the present invention.

Claims

1. A flexible-rigid composite pile, characterized in that: include: A rigid pile with a core pile, wherein the rigid pile is configured as a prefabricated concrete pipe pile, and the concrete pipe pile has a pile body with blades and a conical pile head; The cement-soil bulk pile is configured to be formed by grouting during the rotary drilling and vibration pile-forming process of the rigid pile.

2. The flexible-rigid composite pile according to claim 1, characterized in that: The blades of the bladed pile body are configured as single spiral blades integrally connected to the outer surface of the pile body.

3. The flexible-rigid composite pile according to claim 2, characterized in that: The single spiral blade is integrally arranged at one end close to the cone pile head.

4. The flexible-rigid composite pile according to claim 1, characterized in that: The core pile is configured as a cast-in-place reinforced concrete structure, which is formed inside the top end of the concrete pipe pile. The binding steel bars of the reinforced concrete structure have connecting steel bars extending above the ground, and the connecting steel bars are used to connect the base structure.

5. The flexible-rigid composite pile according to claim 4, characterized in that: The connecting steel bar is configured in the shape of a cone, and the connecting steel bar is butted against the binding steel bars of the reinforced concrete structure through the small end of the cone.

6. The flexible-rigid composite pile according to any one of claims 1 to 5, characterized in that: The rigid pile and the cement-soil bulk pile adopt an equal core structure.

7. A construction method of a flexible-rigid composite pile according to any one of claims 1 to 6, characterized in that: The following steps are involved: Making the rigid pile without a core pile; constructing the rigid piles on the ground at predetermined pile positions; During the pile sinking process, soil is taken and grouting is performed simultaneously to construct cement-soil bulk piles; Before the cement-soil bulk pile begins to set, the rigid pile is sunk to the designed elevation; By tying steel bars and pouring concrete, a support plate and a core pile are constructed inside the rigid pile; The construction is completed after the cement soil on the sides and ends of the rigid pile is solidified.

8. The construction method according to claim 7, characterized in that: The method of making the rigid pile without a core pile specifically comprises: A steel cage in the form of a tube is processed, and the conical pile head and blades are welded to the end and outer wall of the cage respectively, and concrete is poured into the steel cage to form the pile body with blades.

9. The construction method according to claim 7, characterized in that: Constructing the rigid pile on the ground at the predetermined pile position specifically includes: During construction, rotary drilling and vibration are used to form piles, and the pile body with blades is used to take soil.

10. The construction method according to claim 7, characterized in that: During the pile sinking process, soil is taken and grouting is performed simultaneously to construct cement soil bulk piles, which specifically include: After the bladed pile body of the rigid pile enters a predetermined depth below the ground, grouting is injected into the surrounding soil of the bladed pile body below the ground.

Images