Construction method of steel pipe pile

Abstract

The invention relates to the technical field of wharf steel pipe pile construction, in particular to a steel pipe pile construction method which comprises the following steps that a steel pipe pile guide frame is installed at the current preset construction position; the corresponding number of steel pipe piles are hoisted into a plurality of guide frames, the perpendicularity of the steel pipe piles is adjusted, and the steel pipe piles are fixed through guide wheels on the guide frames; sinking the steel pipe pile to a first designed elevation by using a vibration method; the steel pipe pile guide frame is dismantled, and the steel pipe pile continues to be sunk to the second design elevation through the hammering method; if the remaining unconstructed predetermined construction position exists, the steel pipe pile guide frame is installed to the next predetermined construction position; and the steps are repeated till pile sinking construction of all the steel pipe piles is completed. After the steel pipe pile guide frame is moved and reinstalled every time, pile sinking construction can be conducted on a plurality of steel pipe piles at a time, so that the moving frequency of the steel pipe pile guide frame is reduced, the overall construction time is shortened, and the construction efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of dock steel pipe pile construction, and in particular to a steel pipe pile construction method. Background Art

[0002] In dock construction projects, steel pipe piles are widely used as pile foundation materials, especially in dock construction near rivers, seas, lakes and other water bodies, where a large number of steel pipe piles are usually required to be installed in batches. Currently, the industry generally uses steel pipe pile guide frames to assist in the sinking of steel pipe piles. This technology aims to ensure that steel pipe piles can be accurately and efficiently sunk into the designated position.

[0003] However, the traditional steel pipe pile guide frame can only support the sinking of a single steel pipe pile at a time. The specific operation process includes: first, the steel pipe pile guide frame is installed at the predetermined position, then the steel pipe pile is aligned and installed on the guide frame, and then the pile sinking operation is started until the steel pipe pile reaches the predetermined depth. After completing the sinking of a steel pipe pile, the guide frame needs to be moved to the next predetermined position, and the above steps are repeated to construct the next steel pipe pile.

[0004] Although this one-by-one approach is technically mature, it has significant defects: the steel pipe pile guide frame needs to be moved frequently, resulting in slow overall steel pipe pile construction progress and low construction efficiency. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art that the steel pipe pile guide frame needs to be frequently moved, resulting in slow overall steel pipe pile construction progress and low construction efficiency, and to provide a steel pipe pile construction method.

[0006] The present invention provides a construction method of a steel pipe pile, comprising the following steps:

[0007] S1: installing a steel pipe pile guide frame to a currently scheduled construction position; the steel pipe pile guide frame comprises a plurality of guide frames, and the arrangement of the plurality of guide frames is consistent with the position of the currently scheduled steel pipe pile to be constructed;

[0008] S2: Hanging a corresponding number of steel pipe piles into a plurality of the guide frames, adjusting the verticality of the steel pipe piles, and fixing the steel pipe piles using guide wheels on the guide frames;

[0009] S3: sinking the steel pipe pile to a first design elevation using a vibration method;

[0010] S4: dismantling the steel pipe pile guide frame, and continuing to sink the steel pipe pile to the second design elevation by hammering; if there is a scheduled construction position remaining that has not been constructed, installing the steel pipe pile guide frame to the next scheduled construction position;

[0011] S5: Repeat steps S2 to S4 until all the steel pipe pile sinking construction is completed.

[0012] The present invention provides a steel pipe pile construction method, wherein the steel pipe pile guide frame can fix a plurality of the steel pipe piles at one time, and after each movement and reinstallation of the steel pipe pile guide frame, the plurality of steel pipe piles can be sunk at one time, thereby reducing the movement times of the steel pipe pile guide frame, thereby shortening the overall construction time and improving the construction efficiency.

[0013] The vibration method is a method of sinking steel pipe piles into the foundation by using high-frequency vibration and exciting force generated by a vibrator. Under the action of the vibration force, the stratum will be squeezed and liquefied, forming a contact surface that is convenient for the steel pipe piles to sink. The vibration method can be implemented by applying a high-frequency hydraulic vibrator hammer or an electric vibrator hammer. The vibration method is characterized by a high vibration frequency and a small single vibration amplitude. During the pile sinking stage assisted by the steel pipe pile guide frame, it is helpful to reduce interference with the steel pipe pile guide frame and avoid excessive impact force causing the steel pipe pile guide frame to deviate, thereby ensuring the smooth progress of subsequent construction.

[0014] The hammering method utilizes the instantaneous impact mechanical energy of the pile hammer when it falls to overcome the resistance of the soil to the pile, destroy its static equilibrium state, cause the pile body to sink, and reach a new static pressure equilibrium state. The hammering method can be implemented by using a diesel impact hammer or a hydraulic impact hammer. The vibration method is characterized by a low vibration frequency, but a large amplitude of each vibration, and a strong hammering force generated at a single time. When the steel pipe pile guide frame has been dismantled, this method can more effectively accelerate the sinking of the steel pipe pile to the second design elevation.

[0015] The second design elevation means that the bottom position of the steel pipe pile has reached the predetermined bearing layer according to the design requirements.

[0016] Preferably, in step S3, when the number of the steel pipe piles is greater than or equal to 3, step S3 includes the following steps:

[0017] S31: sinking the steel pipe piles at the two ends to a predetermined height;

[0018] S32: sinking the middle steel pipe pile or two steel pipe piles to the predetermined height;

[0019] S33: If there are any remaining steel pipe piles that have not been sunk, sink the remaining steel pipe piles to the predetermined height;

[0020] S34: Repeat steps S31 to S33 to sink all the current steel pipe piles to the first design elevation.

[0021] In this solution, the steel pipe piles at the two ends are first driven, and then the steel pipe pile or two steel pipe piles in the middle are driven, and finally the remaining steel pipe piles are driven. This solution allows the steel pipe pile guide frame to use the steel pipe piles that have been driven as fixed support points, thereby improving the overall stability of the steel pipe pile guide frame. In particular, the steel pipe piles at the two ends and the middle are first driven, so that the two ends and the middle of the steel pipe pile guide frame can be quickly fixed and supported, thereby improving the overall stability of the steel pipe pile guide frame more quickly.

[0022] The predetermined height may be the distance that the steel pipe pile sinks to the first design elevation at one time, or may be 1 meter to 3 meters, or 1 / 10-1 / 5 of the height of the steel pipe pile.

[0023] Preferably, in step S31 to step S33, the predetermined height is 1 / 10-1 / 5 of the height of the steel pipe pile.

[0024] In this solution, each of the steel pipe piles on the steel pipe pile guide frame is first sunk to a predetermined height, and then this step is repeated until all the steel pipe piles are sunk to the first design elevation. This solution allows the steel pipe pile guide frame and the steel pipe piles to interact with each other to form a stable whole during multiple sinking processes, which is beneficial to improving the pile sinking effect. This can prevent the steel pipe pile guide frame from having a large positional offset when some steel pipe piles are sunk to the first design elevation at one time, thereby hindering the smooth sinking of subsequent steel pipe piles.

[0025] At the same time, the method of sinking in stages and multiple times can not only monitor the verticality of the suspended steel pipe piles, but also make corresponding adjustments based on the monitoring data to ensure the quality of pile sinking. This method also helps to quickly discover possible problems that may occur during the pile sinking process, such as soil heave, thereby reducing risks during the construction process.

[0026] Preferably, in step S31-step S34, except for the last steel pipe pile that is sunk to the first design elevation, after the other steel pipe piles are sunk to the predetermined height or to the first design elevation, the pile bodies of the other steel pipe piles are temporarily fixed to the steel pipe pile guide frame. This solution can increase the fixed support points of the steel pipe pile guide frame and the steel pipe piles that have been sunk, so that the steel pipe pile guide frame can further use the steel pipe piles that have been sunk to improve the overall stability of the steel pipe pile guide frame.

[0027] The temporary fixing method may be to spot-weld the pile body of the steel pipe pile and the steel pipe pile guide frame, or to connect the pile body of the steel pipe pile and the steel pipe pile guide frame using a clamping tool.

[0028] Preferably, the temporary fixation between the pile body of the steel pipe pile and the steel pipe pile guide frame is achieved by a clamping component. This solution simplifies the temporary fixation setting process and makes the subsequent temporary fixation removal work faster and easier.

[0029] Preferably, in step S3, during the pile sinking process, the verticality allowable deviation of the steel pipe pile is limited to within 1%.

[0030] Preferably, in step S3, an electric vibratory hammer is used to sink the steel pipe pile. Compared with a high-frequency hydraulic vibratory hammer, the electric vibratory hammer has a simpler structure and lower cost. At the same time, the maintenance of the electric vibratory hammer is relatively simple and the maintenance cost is lower.

[0031] Preferably, in step S4, a diesel impact hammer is used to sink the steel pipe pile. In the second half of the steel pipe pile sinking operation, as the pile body gradually penetrates into the soil, the required impact force also increases to ensure that the pile end of the steel pipe pile can penetrate the soil layer and reach the predetermined design depth. The diesel impact hammer, with its ability to generate higher impact kinetic energy, enables the steel pipe pile to continue to sink until the bottom of the steel pipe pile can be sunk to the design elevation. Compared with a hydraulic impact hammer, the maintenance of the diesel impact hammer is relatively simple and has lower maintenance costs.

[0032] Preferably, in step S3, the first design elevation refers to when the bottom of the steel pipe pile passes through the sand layer, or when the top elevation of the steel pipe pile is higher than the guide frame by 0.5 to 1.0 meters. The vibration method uses a vibrating hammer to clamp the top of the steel pipe pile. The first design elevation is defined as when the top elevation of the steel pipe pile is higher than the guide frame by 0.5 to 1.0 meters. This is to maximize the use of the steel pipe pile guide frame to sink the steel pipe pile, while preventing the vibrating hammer from colliding with the guide frame, which may cause damage to the guide frame or the steel pipe pile guide frame.

[0033] Preferably, the method further includes S6: performing high-strain dynamic testing on the steel pipe piles after the pile driving construction is completed. This scheme is to understand the axial bearing capacity and overall integrity of the steel pipe piles, so as to take corresponding measures to correct the problems or defects found according to the test results.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1. The present invention provides a steel pipe pile construction method, which can carry out pile sinking construction on a plurality of steel pipe piles at one time after each movement and reinstallation of the steel pipe pile guide frame, thereby reducing the number of times the steel pipe pile guide frame is moved, thereby shortening the overall construction time and improving construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The present invention is a flow chart of a construction method of steel pipe piles.

[0037] Figure 2 Schematic diagram of pile sinking in step S3 in Example 1.

[0038] Markings in the figure:

[0039] 1-Steel pipe piles,

[0040] 2-Steel pipe pile guide frame,

[0041] 3- Foundation. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0043] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or are the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.

[0044] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0045] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0046] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0047] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0048] Example 1

[0049] Figure 1 A flow chart of a steel pipe pile construction method of the present application is shown, and the construction method of the present application is explained below using a certain wharf project as an example.

[0050] The wharf project has a total of 784 steel pipe piles 1, all of which are constructed using onshore piling technology. The 784 steel pipe piles 1 are divided into 112 rows and arranged at a certain interval along the coast. Each row contains 7 steel pipe piles 1, and the relative positions of the steel pipe piles 1 in all rows remain consistent. The steel pipe pile guide frame 2 used includes 7 guide frames, the relative positions of the 7 guide frames match the relative positions of the steel pipe piles 1 in each row, and the 7 guide frames are all connected to the first horizontal longitudinal component at the top of the steel pipe pile guide frame 2.

[0051] When the steel pipe pile 1 is subjected to pile sinking operation, the following steps are specifically included:

[0052] S1: Install the steel pipe pile guide frame 2 to the location where the first row of steel pipe piles 1 are scheduled to be constructed on the wharf project. The steel pipe pile guide frame 2 includes a plurality of guide frames, and the arrangement of the plurality of guide frames is consistent with the location of the steel pipe piles 1 to be constructed.

[0053] Before the implementation of step S1, the construction site of the steel pipe pile 1 can be leveled, specifically including flattening the raised parts and backfilling the low-lying areas to ensure the flatness of the site surface. If the low-lying area is a pool or fish pond, the silt in the water body or fish pond needs to be replaced. After the site is leveled, safeguard measures are taken according to the actual situation of the foundation 3 by placing steel plates, roadbed plates, etc. In step S1, a crane or crawler crane can be used to transport the steel pipe pile guide frame 2 to the corresponding position and install it.

[0054] S2: Hang a corresponding number of steel pipe piles 1 into several guide frames, adjust the verticality of the steel pipe piles 1, and use the guide wheels on the guide frames to fix the steel pipe piles 1. Specifically, the length of the steel pipe pile 1 is 25.2 meters to 37.2 meters. Two holes are opened in the pile head of the steel pipe pile 1 before leaving the factory for hanging the pile, and two-end hanging is adopted when unloading. When the steel pipe pile 1 is hung into the corresponding guide frame, the pile head of the steel pipe pile 1 is hung at two points, and a steel wire rope is used to pass through the two opened holes respectively, and the steel wire rope is connected to the hook of the crane. By adjusting the relative position of the crane arm and the steel pipe pile 1, the hook rises slowly, and one end of the steel pipe pile 1 rises slowly. During the lifting process, the hook remains basically vertical. After the steel pipe pile 1 is vertical, the position and height are adjusted, and it is placed in the corresponding guide frame. The hook is raised and lowered slowly. Rubber sheets or rubber wheels are installed on the guide frame in the area where friction with the steel pipe pile 1 may occur, so as to prevent scratches on the coating of the steel pipe pile 1 when the pile is hoisted. After the bottom end of the steel pipe pile 1 contacts the surface of the foundation 3, check whether the verticality of the steel pipe pile 1 meets the requirements. If it does not meet the requirements, it needs to be re-lifted for adjustment. After the verticality of the steel pipe pile 1 meets the requirements, use a dehooker to decouple it and separate the steel wire rope from the steel pipe pile 1.

[0055] S3: Using a vibration method to sink the steel pipe pile 1 to a first designed elevation.

[0056] like Figure 2 As shown, step S3 may include the following steps:

[0057] S31: sinking the two steel pipe piles 1 at the two ends to a predetermined height;

[0058] S32: sinking the middle steel pipe pile 1 to a predetermined height;

[0059] S33: sinking the remaining four steel pipe piles 1 to the predetermined height;

[0060] S34: repeating steps S31 to S33 to sink all the steel pipe piles 1 currently to the first design elevation.

[0061] Figure 2A schematic diagram showing various steps of sinking the steel pipe pile 1 to a first design elevation using a vibration method is shown. Figure 2 The hollow arrows in the diagram indicate the sequence of construction steps, showing the progression from one step to the next. Figure 2 A total of 6 step diagrams are shown in the figure, which are:

[0062] The steel pipe pile 1 is hoisted into place and fixed;

[0063] The steel pipe piles 1 at the two ends are sunk to a predetermined height;

[0064] The middle steel pipe pile 1 is sunk to a predetermined height;

[0065] The remaining steel pipe piles 1 are sunk to a predetermined height;

[0066] Continue with the next round of sinking operations;

[0067] All steel pipe piles 1 are sunk to the first design elevation.

[0068] The predetermined height is 1 / 10-1 / 5 of the height of the steel pipe pile 1, and can be specifically 1 / 10, 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5 of the height of the steel pipe pile 1. In this embodiment, 1 / 5 of the height of the steel pipe pile 1 is selected as the predetermined height. For a steel pipe pile 1 with a length of 25.2 meters to 37.2 meters, the specific value of the predetermined height is 5.04 meters to 7.44 meters.

[0069] The first design elevation refers to the elevation when the bottom of the steel pipe pile 1 passes through the sand layer, or when the top elevation of the steel pipe pile 1 is 0.5 to 1.0 meters higher than the guide frame. The specific higher range can be 0.5 meters, 0.6 meters, 0.7 meters, 0.75 meters, 0.8 meters, 0.9 meters, and 1.0 meters.

[0070] In step S31-step S34, except for the last steel pipe pile 1 that is sunk to the first design elevation, after the other steel pipe piles 1 are sunk to the predetermined height or to the first design elevation, the pile bodies of the other steel pipe piles 1 are temporarily fixed to the steel pipe pile guide frame 2. Specifically, the steel pipe pile guide frame 2 is further provided with a second horizontal longitudinal component at a portion close to the ground, the second horizontal longitudinal component is perpendicular to the steel pipe pile 1, and a clamping component is provided on the second horizontal longitudinal component, and the temporary fixation between the pile body of the steel pipe pile 1 and the steel pipe pile guide frame 2 is achieved by the clamping component.

[0071] During the pile sinking process, the verticality of the steel pipe pile 1 is checked at any time, and the verticality allowable deviation of the steel pipe pile 1 is limited to within 1%. If the verticality allowable deviation of the steel pipe pile 1 exceeds the limit, the steel pipe pile 1 needs to be corrected and adjusted, and the pile sinking can continue after the requirements are met.

[0072] Specifically, an electric vibrating hammer can be used to sink the steel pipe pile 1, and the electric vibrating hammer can be lifted by a crawler crane. Specifically, the electric vibrating hammer can be an EP270 vibrating hammer or an EP200 vibrating hammer.

[0073] S4: dismantle the steel pipe pile guide frame 2, and continue to sink the steel pipe pile 1 to the second design elevation using a hammering method; if there are any remaining scheduled construction positions that have not been constructed, install the steel pipe pile guide frame 2 to the next scheduled construction position.

[0074] The second design elevation means that the bottom position of the steel pipe pile 1 has reached the predetermined bearing layer according to the design requirements.

[0075] When dismantling the steel pipe pile guide frame 2, the clamping component needs to be separated from the steel pipe pile 1 to release the temporary fixation of the steel pipe pile 1. If all 112 rows of steel pipe piles 1 have been subjected to the pile sinking operation of this step, after the steel pipe pile guide frame 2 is dismantled for the last time, the steel pipe pile guide frame 2 is put back into the predetermined site or warehouse.

[0076] In this step, the order of sinking the seven steel pipe piles 1 may be from left to right.

[0077] Specifically, a diesel impact hammer can be used to sink the steel pipe pile 1, and the diesel impact hammer can be lifted by a crawler crane. Specifically, the diesel impact hammer can be a D160 diesel impact hammer.

[0078] In this step, when the corresponding steel pipe pile 1 is sunk to a pile top elevation lower than the ground elevation and the corresponding steel pipe pile 1 has not yet sunk to the designed elevation, a pile driver can be used to continue to sink the steel pipe pile 1 to the designed elevation.

[0079] S5: Repeat steps S2 to S4 until all 112 rows of steel pipe piles 1 are completed.

[0080] S6: Perform high-strain dynamic testing on the steel pipe piles 1 that have been completed by pile driving construction, and take corresponding measures to correct the steel pipe piles 1 that are found to have problems or defects.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A construction method for steel pipe piles, characterized in that: The following steps are involved: S1: installing a steel pipe pile guide frame to a currently scheduled construction position; the steel pipe pile guide frame comprises a plurality of guide frames, and the arrangement of the plurality of guide frames is consistent with the position of the currently scheduled steel pipe pile to be constructed; S2: Hanging a corresponding number of steel pipe piles into a plurality of guide frames, adjusting the verticality of the steel pipe piles, and fixing the steel pipe piles using guide wheels on the guide frames; S3: sinking the steel pipe pile to a first design elevation using a vibration method; S4: dismantling the steel pipe pile guide frame, and continuing to sink the steel pipe pile to the second design elevation by hammering; if there is a scheduled construction position remaining that has not been constructed, installing the steel pipe pile guide frame to the next scheduled construction position; S5: Repeat steps S2 to S4 until all the steel pipe pile sinking construction is completed.

2. A construction method for steel pipe piles according to claim 1, characterized in that: In step S3, when the number of the steel pipe piles is greater than or equal to 3, step S3 includes the following steps: S31: sinking the steel pipe piles at the two ends to a predetermined height; S32: sinking the middle steel pipe pile or two steel pipe piles to the predetermined height; S33: If there are any remaining steel pipe piles that have not been sunk, sink the remaining steel pipe piles to the predetermined height; S34: Repeat steps S31 to S33 to sink all the current steel pipe piles to the first design elevation.

3. A construction method for steel pipe piles according to claim 2, characterized in that: In step S31 to step S33, the predetermined height is 1 / 10-1 / 5 of the height of the steel pipe pile.

4. A construction method for steel pipe piles according to claim 3, characterized in that: In step S31 to step S34, except for the last steel pipe pile that is sunk to the first design elevation, after the other steel pipe piles are sunk to the predetermined height or to the first design elevation, the pile bodies of the other steel pipe piles are temporarily fixed to the steel pipe pile guide frame.

5. A construction method for steel pipe piles according to claim 4, characterized in that: The temporary fixation between the pile body of the steel pipe pile and the steel pipe pile guide frame is achieved by means of a clamping component.

6. A construction method for steel pipe piles according to any one of claims 1 to 5, characterized in that: In step S3, during the pile sinking process, the verticality allowable deviation of the steel pipe pile is limited to within 1%.

7. A construction method for steel pipe piles according to claim 6, characterized in that: In step S3, an electric vibratory hammer is used to perform pile sinking construction on the steel pipe pile.

8. The construction method of a steel pipe pile according to claim 6, characterized in that: In step S4, a diesel impact hammer is used to sink the steel pipe piles.

9. A construction method for steel pipe piles according to claim 6, characterized in that: In step S3, the first design elevation refers to when the bottom of the steel pipe pile passes through the sand layer, or when the top elevation of the steel pipe pile is higher than the guide frame by 0.5 m to 1.0 m.

10. A construction method for steel pipe piles according to claim 6, characterized in that: It also includes S6: conducting high-strain dynamic testing on the steel pipe piles that have been completed by the pile driving construction.

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