Single pile guide frame

Abstract

The utility model relates to a single-pile guide frame which comprises a single-pile foundation, a guide frame and an inclined support connecting the single-pile foundation and the guide frame. The lower end of the single pile is vertically inserted into a seabed rock stratum, and the top of the single pile is exposed out of the sea surface; the guide frame is of a rectangular beam structure with the middle sitting on the top of the single pile, and guide cylinders are symmetrically arranged at the two ends of the guide frame. The device can adapt to the operation of the seabed abrupt slope cast-in-situ bored pile, the construction operation process is relatively simple, the construction cost is low, the operation efficiency is high, and a small floating crane can be used for operation.

Description

Technical Field

[0001] The utility model belongs to the technical field of offshore bored pile construction, and in particular relates to a single pile guide frame used for offshore drilling and rock embedding. Background Art

[0002] When offshore construction projects are located in shallow waters, the foundation form of a jacket is often used. When the seabed conditions are complex, for example, the jacket needs to be located on a steep slope, and the surface of the steep slope is a certain thickness of soft soil, and below the soft soil is a certain thickness of rock layer. In this case, because the slope is very steep, the surface soft soil is extremely unstable under the marine environmental forces such as earthquakes or the forces of pile construction, and landslides are prone to occur. Therefore, during the installation of the jacket platform support positioning piles (hereinafter referred to as jacket piles), it is not advisable for the jacket piles to only penetrate the surface soft soil. They need to be embedded in the rock to ensure safety. Vibratory hammers or impact hammers cannot be used to pile, which have a great impact on the stability of the surface soil. This requires the use of bored cast-in-place piles, a method that has the least impact on the surface soft soil.

[0003] When constructing the jacket pile, the installation method is to sink the pile first and then insert it into the jacket platform foundation. The jacket is generally a structure with more than three legs, and there is a certain distance between the legs. Usually, the distance from the center of the jacket to the center of each leg is equal. Correspondingly, the number and position of the jacket piles correspond to the jacket legs. At present, there are mainly two forms of bored pile operations on steep seabed slopes:

[0004] Form 1: survey and locate each drilling position of each jacket pile, build a guide cylinder for the jacket pile at the drilling position, use the guide cylinder to install the steel casing, then drill holes in the casing using a drilling rig arranged on the guide cylinder structure, place the jacket pile in the steel casing, pour concrete, and remove the steel casing and guide cylinder.

[0005] Form 2 uses multiple pile guide frames to be put in place at one time to complete the positioning, insertion and pouring of each pipe frame pile in sequence.

[0006] In the seabed steep slope bored cast-in-place pile operation of the prior art form 1, each installation position of the jacket pile needs to be individually surveyed and positioned and drilled, the overall operation process is complicated, positioning errors are prone to occur, and the relative position accuracy between the piles is low; in the seabed steep slope bored cast-in-place pile operation of the prior art form 2, it is necessary to install a multi-pile guide frame, the guide frame itself is heavy, and a large floating crane needs to be used for installation and removal, the construction cost is high, especially the steep slope conditions of the seabed also limit the use of large floating cranes.

[0007] Therefore, there is an urgent need for an offshore drilling guide frame that can adapt to the bored pile operation on the steep slope of the seabed, has a simple construction process, low construction cost, high operation efficiency, and can meet the operation requirements using only a small floating crane. Summary of the invention

[0008] The purpose of the utility model is to overcome the above-mentioned shortcomings and provide a single pile guide frame that can adapt to the operation of bored piles on steep slopes of the seabed, and has a relatively simple construction process, low construction cost, high operation efficiency, and can use a small floating crane for operation.

[0009] The purpose of the utility model is achieved in this way:

[0010] A single pile guide frame comprises a single pile foundation, a guide frame, and an inclined support connecting the single pile foundation and the guide frame;

[0011] The monopile foundation comprises a monopile with the lower end vertically inserted into the seabed rock layer and the top exposed above the sea surface;

[0012] The guide frame is a rectangular beam structure with the middle portion sitting on the top of the single pile, and guide cylinders are symmetrically arranged at both ends of the guide frame;

[0013] The inclined support comprises an upper inclined support symmetrically installed at the bottom of both sides of the guide frame and a plurality of lower inclined supports evenly arranged on the upper outer circumference of the single pile; the upper inclined support and the lower inclined support are connected by flanges.

[0014] Furthermore, the number of the lower oblique supports is not less than the number of the pipe frame piles to be installed.

[0015] Furthermore, the number of the guide cylinders is an even number, and they are symmetrically arranged at both ends of the guide frame.

[0016] Furthermore, a plurality of protruding pads are provided on the outer circumference of the portion where the lower portion of the single pile is inserted into the seabed rock formation.

[0017] Furthermore, the contact portion between the bottom of the guide frame and the top of the single pile is welded and connected via a fillet weld.

[0018] Furthermore, a limiting block for installing a counterweight or a drilling rig is provided on the top of the guide frame.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] The utility model adopts a single pile guide frame in the form of a single pile foundation. First, a hole is drilled at the center of the position where the conductor frame is to be installed to install the single pile. Then, the guide frame is rotated so that the guide cylinder on the guide frame automatically locates the positions of all conductor frame piles to be installed, thereby reducing the construction difficulty and eliminating the need for repeated surveying and positioning. The position deviation between the piles is small, the accuracy is high, the operation efficiency is high, and the operation cost is low. The single pile and the guide frame are separately disassembled and assembled, and the weight of a single component is low, which significantly reduces the floating crane capacity requirement. A small floating crane can meet the construction needs, thereby greatly reducing the construction cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The utility model is a schematic diagram of the installation structure of a single pile guide frame.

[0022] Figure 2 The utility model is a schematic diagram of a single pile foundation structure of a single pile guide frame.

[0023] Figure 3 The utility model is a schematic diagram of a guide frame structure of a single pile guide frame.

[0024] Figure 4 The utility model is a schematic diagram of the working state of a single pile guide frame.

[0025] Figure 5 The utility model is a schematic diagram of the installation and construction of a four-legged conductor frame.

[0026] Figure 6 The utility model is a top view of the first pile construction process of a pipe frame pile installation method.

[0027] Figure 7 The utility model is a top view of the construction process of three or four piles of a pipe frame pile installation method.

[0028] Figure 8 The utility model is a top view of a preferred single pile corresponding to a three-legged jacket in a jacket pile installation method.

[0029] Fig. 9 The utility model is a top view of the construction of a six-legged conductor frame according to a conductor frame pile installation method.

[0030] in:

[0031] Guide frame 1, single pile 2, guide cylinder 3, upper oblique support 4, lower oblique support 5, jacket pile 6, liner 7, limit block 8, counterweight block 9, drilling rig 10, jacket 11. DETAILED DESCRIPTION Embodiment 1:

[0032] See also Figure 1~Figure 5 The utility model relates to a single pile guide frame, comprising a single pile foundation, a guide frame 1, and an inclined support connecting the single pile foundation and the guide frame 1;

[0033] The monopile foundation comprises a monopile 2 with its lower end vertically inserted into the seabed rock layer and its top exposed above the sea surface; a plurality of protruding pads 7 are provided on the outer circumference of the portion of the monopile 2 inserted into the seabed rock layer, which are used to increase the grouting contact area, improve the grouting connection performance, and improve the bonding force between the monopile 2 and the rock layer;

[0034] The guide frame 1 is a rectangular beam structure with the middle part sitting on the top of the single pile 2. The two ends of the guide frame 1 are symmetrically provided with guide cylinders 3. The center distance between the guide cylinder 3 on one side of the guide frame 1 and the single pile 2 is equal to the center distance between the center position of the jacket pile 6 and the jacket 11. Figure 3 When the center distances of the jacket piles 6 and the center position of the jacket 11 are different, multiple guide cylinders 3 can be set on the guide frame 1 to adapt to them. For example, the jacket piles 6 of the six-leg jacket 11 include four corner piles and two side piles, and the distances between the two and the center of the jacket 11 are different. Then four symmetrical guide cylinders 3 can be set on the guide frame 1 to adapt them respectively, the two outer guide cylinders 3 are adapted to the four corner piles, and the two inner guide cylinders 3 are adapted to the two side piles, see Fig. 9 ;

[0035] The contact part between the bottom of the guide frame 1 and the top of the single pile 2 can be connected by corner weld welding or bolt matching; a limit block 8 for installing a counterweight 9 or a drilling rig 10 is provided on the top of the guide frame 1, and a drilling rig is arranged on the guide frame 1 to drill holes in the rock formation; the counterweight 9 and the drilling rig 10 are symmetrically arranged on both sides of the guide frame 1 to adjust the force balance of the guide frame 1, reduce the internal stress of the guide frame 1, reduce the external force of the contact part of the guide frame 1 and the single pile 2, reduce the internal stress of the oblique support, and realize the optimization of the overall structure of the single pile guide frame;

[0036] The inclined support comprises an upper inclined support 4 symmetrically installed at the bottom of both sides of the guide frame 1, and a plurality of lower inclined supports 5 evenly arranged on the upper outer circumference of the single pile 2; the upper inclined support 4 and the lower inclined support 5 are connected by a flange;

[0037] The number of the lower oblique supports 5 is not less than the number of the jacket piles 6 to be installed, for example, if the jacket 11 has three legs, the number of the lower oblique supports 5 on the single pile 2 is not less than three, and can be three or six; if the jacket 11 has four legs, the number of the lower oblique supports 5 on the single pile 2 is four; if the jacket 11 has six legs, the number of the lower oblique supports 5 on the single pile 2 is six; Embodiment 2:

[0038] On the basis of the single pile guide frame of Example 1, when the jacket frame 11 has four legs, the jacket frame 11 and the jacket frame pile 6 are installed. Figure 5 The number of lower inclined supports 5 on the single pile 2 is four, see Figure 2 ; For the specific working principle, please refer to Construction Example 5; Embodiment 3:

[0039] On the basis of the single pile guide frame of Example 1, when the jacket frame 11 has three legs, the number of the lower oblique supports 5 on the single pile 2 is three or six. Figure 8; For the specific working principle, please refer to Construction Example 6; Embodiment 4:

[0040] On the basis of the single pile guide frame of Example 1, when the jacket frame 11 has six legs, the number of the lower oblique supports 5 on the single pile 2 is six, and the number of the guide cylinders 3 is four. Fig. 9 ; For the specific working principle, please refer to Construction Example 7. Embodiment 5:

[0041] Based on Example 2, the pipe frame 11 has four legs. Figure 5 The specific installation process of the jacket pile 6 includes the following steps:

[0042] 1) Single pile installation

[0043] A. Determine the center point of the jacket; determine the center position of the jacket installation through surveying and positioning;

[0044] B. Single pile sleeve installation: Install the single pile sleeve at the center position;

[0045] C. Arrange the drilling rig and drill holes in the rock. The drilling rig drills holes at the center and the drilling depth must reach the seabed rock layer to ensure that the rock layer provides sufficient support for the single pile;

[0046] D. Insert the single pile and grout the part where it enters the rock section; insert the single pile 2 into the single pile sleeve, insert the bottom of the single pile 2 into the rock formation hole, and grout the bottom of the single pile 2 to combine the bottom of the single pile 2 and the rock formation into one; after the single pile 2 and the rock layer are connected by grouting, they can provide sufficient supporting force to resist the horizontal and vertical loads caused by the installation of the jacket pile 6;

[0047] E. Pull out the sleeve; pull out the single pile sleeve to complete the installation of the single pile 2;

[0048] 2) Guide frame installation

[0049] F. Position the guide cylinder on the guide frame above the first pile of the jacket; hoist the guide frame 1 to the top of the single pile 2, adjust the position of the guide frame 1 sitting on the top of the single pile 2, so that the guide cylinder 3 on one side of the guide frame 1 is located above the first pile of the jacket; since the guide frame 1 is a centrally symmetrical structure, and the position of the single pile 2 is at the center of the position where the guide frame 1 is to be installed, the guide cylinder 3 of the guide frame 1 corresponds to the position of the jacket pile 6 to be installed; thanks to the separate design of the guide frame 1 and the single pile 2, the guide frame 1 itself has a simple structure and light weight, and only needs a small floating crane to lift it, saving construction costs;

[0050] G. The upper oblique support and the lower oblique support are butt-jointed and flange-connected; if the position of the guide cylinder 3 corresponds to the jacket pile 6, the upper oblique support 4 and the lower oblique support 5 can also be matched and connected; therefore, it is only necessary to butt-join the upper oblique support 4 of the guide frame 1 and the lower oblique support 5 of the single pile 2, and the geometrical dimension relationship between the parts can ensure that the position of the guide cylinder 3 and the jacket pile 6 to be installed in step F corresponds;

[0051] H. The bottom of the guide frame and the top of the single pile are welded or bolted; the connection between the bottom of the guide frame 1 and the top of the single pile 2 is welded or bolted by fillet welds, which further stabilizes the connection between the guide frame 1 and the single pile 2 and shares part of the structural force;

[0052] 3) First pile installation

[0053] I. Insert the sleeve from the guide cylinder at the first pile position; insert the sleeve for guiding the jacket pile 6 into the guide cylinder 3 at the first pile position;

[0054] J. Arrange a drilling rig at the first pile position on the guide frame, and arrange counterweights at the symmetrical pile positions; that is, install a drilling rig 10 on the guide frame 1 above the guide cylinder 3 at the first pile position, and extend the drill bit into the sleeve to drill into the seabed and rock formation; at the same time, in order to balance the force of the guide frame 1 and the single pile 2, install a counterweight 9 on the guide frame 1 above the guide cylinder 3 on the other side symmetrical to the guide cylinder 3 of the first pile, reduce the internal stress of the guide frame 1, reduce the external force of the contact part of the guide frame 1 and the single pile 2, reduce the internal stress of the oblique support, and optimize the overall structure of the guide frame;

[0055] K. Drilling rig rock drilling; during the drilling process, as the reaction force of rock drilling gradually increases, the counterweight blocks in the symmetrical position can be gradually reduced to ensure the force balance of the guide frame structure;

[0056] L. Insert the jacket pile and grout the part where it enters the rock section; insert the jacket pile 6 into the sleeve 6 through the guide tube 3 until the bottom of the drilled hole in the rock layer, and grout the part where the jacket pile 6 is inserted into the rock layer, so that the jacket pile 6 is fixedly installed and connected with the rock layer;

[0057] M. Pull out the sleeve to complete the installation of the first jacket pile 6;

[0058] 4) Secondary pile installation

[0059] N. Insert a sleeve into the guide tube at the symmetrical position of the first pile guide tube; exchange the roles of the two symmetrical guide tubes 3, and then install the jacket pile 6 at the diagonal position of the first pile, that is, the secondary pile, the second pile;

[0060] O. Repeat steps J, K, L and M to complete the secondary pile installation;

[0061] 5) Loop installation

[0062] P. Release the connection between the bottom of the guide frame and the top of the single pile; if it is welded, use thermal cutting to separate it; if it is bolted, remove the bolts;

[0063] Q. Release the flange connection between the upper diagonal support and the lower diagonal support; release all connections between the guide frame 1 and the monopile 2;

[0064] R. Position the guide cylinder on the guide frame above the third pile; lift the guide frame 1 and rotate it so that the guide cylinder is above the installation position of the jacket pile, and align the upper oblique support 4 and the lower oblique support 5 to achieve precise alignment;

[0065] S. Repeat steps G to O, wherein the first pile is changed to the third pile, and the second pile is changed to the fourth pile, to complete the installation of the third pile and the fourth pile;

[0066] At this point, the jacket piles 6 of the four-leg jacket 11 of Example 2 are all installed in place. If the number of the jacket 11 legs is an even number greater than four, then step 6) is executed, otherwise, step 7) is continued to complete the construction;

[0067] 6) Installation of remaining piles

[0068] T. Repeat step 5) until all piles are installed;

[0069] 7) Remove the guide frame

[0070] U. Repeat steps P and Q; release the connection between the guide frame 1 and the monopile 2;

[0071] V. Remove the guide frame;

[0072] W. Cut off and remove the single pile at the underwater seabed position to complete the installation construction of the jacket pile 6.

[0073] Embodiment 6:

[0074] On the basis of the basic construction method of Example 5, when the jacket 11 has three legs, that is, the case of Example 3, the installation of the second jacket pile 6, that is, the secondary pile installation method, is to replace the execution steps N and O of step 4) of Example 4 with steps P, Q and R, wherein the third pile is changed to the secondary pile; the execution step S of step 5) of the cyclic installation is changed to only complete the installation of the third pile;

[0075] In order to improve the stability of the connection between the guide frame 1 and the single pile 2, when the jacket frame 11 has three legs, the lower oblique support 5 is preferably set to six, so that the oblique support connection between the guide frame 1 and the single pile 2 is symmetrically connected to form two sets of upper and lower oblique support connection structures, so that the overall structure of the single pile guide frame is more balanced. Figure 8 . Embodiment 7:

[0076] On the basis of the basic construction method of Example 5, when the jacket 11 has six legs, that is, the case of Example 4, after the jacket piles 6 at the four corners are installed, step 5) is performed for circular installation to complete the jacket piles 6 at the two side positions, and the rock-embedded installation construction of all six jacket piles 6 can be completed.

[0077] The utility model adopts a guide frame for bored cast-in-place piles for single pile foundation and rock-embedded application, which is suitable for pile-first jacket foundation, especially when the seabed conditions are relatively complex, there are particularly steep slopes and the surface soft soil is unstable. The single pile itself is first drilled and embedded in the rock, and the piles used for jacket support positioning are also drilled and embedded in the rock, which effectively solves the installation problem of jacket platform piles under such complex seabed conditions.

[0078] In addition: It should be noted that the above specific implementation is only an optimization scheme of this patent. Any changes or improvements made by technicians in this field based on the above concept are within the scope of protection of this patent.

Claims

1. A single pile guide frame, characterized in that: It comprises a monopile foundation, a guide frame (1), and an inclined support connecting the monopile foundation and the guide frame (1); The monopile foundation comprises a monopile (2) with the lower end vertically inserted into the seabed rock layer and the top exposed above the sea surface; The guide frame (1) is a rectangular beam structure with its middle portion sitting on top of the single pile (2), and guide cylinders (3) are symmetrically arranged at both ends of the guide frame (1); The inclined support comprises an upper inclined support (4) symmetrically mounted on the bottom of both sides of the guide frame (1), and a plurality of lower inclined supports (5) mounted on the upper outer circumference of the single pile (2) and evenly arranged; the upper inclined support (4) and the lower inclined support (5) are connected via a flange.

2. The single pile guide frame according to claim 1, characterized in that: The number of the lower inclined supports (5) is not less than the number of the jacket piles (6) to be installed.

3. The single pile guide frame according to claim 1, characterized in that: The number of the guide cylinders (3) is an even number, and they are symmetrically arranged at both ends of the guide frame (1).

4. The single pile guide frame according to claim 1, characterized in that: A plurality of protruding pads (7) are provided on the outer circumference of the lower portion of the monopile (2) inserted into the seabed rock formation.

5. The single pile guide frame according to claim 1, characterized in that: The contact portion between the bottom of the guide frame (1) and the top of the monopile (2) is welded and connected via a fillet weld.

6. The single pile guide frame according to claim 1, characterized in that: A limit block (8) for mounting a counterweight block (9) or a drilling rig (10) is provided on the top of the guide frame (1).

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