Combined pile group control system and method of steel casing-steel pipe piles in water environment

Abstract

The invention discloses a combined pile group control system and method of steel casing-steel pipe piles in a water environment, wherein the combined pile group comprises a steel casing, a steel track assembly and a combined steel rod truss; the steel track assembly comprises a plurality of vertical steel tracks arranged on the outer wall of the steel casing and a horizontal steel track arranged at the bottom of the vertical steel track and horizontally arranged along the circumference of the outer wall of the steel casing; the combined steel rod truss comprises a plurality of steel rod truss units which simultaneously comprise steel rod limiters, steel rods and steel pile limiters; grouting pipes are respectively arranged on the lower sides of the inner walls of the steel casing and the steel piles; the control system comprises an axial force strain gauge, an underwater controllable jack and a ground management system; the axial force change of the pile group structure during actual operation is measured by the steel rod axial force strain gauge, and is input and output to the ground management system; the position of the steel rod limiter is adjusted by the underwater controllable jack, so that the axial force of the overall truss structure is evenly distributed to a limited range, thereby realizing real-time monitoring and adjustment of the stability of the combined pile group structure.

Description

Technical Field

[0001] The present invention belongs to the technical field of underwater pile foundation engineering, and more specifically, relates to a combined pile group control system and method of steel casing-steel pipe piles in a water environment. Background Art

[0002] In water conservancy projects, when bored piles are set up in underwater environments, steel casings are usually used to form cofferdams to determine the position of the pile body, isolate water from entering the borehole, and effectively protect the pile body. After the construction is completed, it is generally retained as part of the permanent structure. When considering horizontal extreme loads (earthquakes, ship collisions), its actual bearing capacity must be utilized, and the premise is to maintain the joint action state of the steel casing and the pile. According to current research findings, in water conservancy projects, after the steel casing is sunk to a predetermined depth, the combined pile structure of the steel casing and bored piles can give full play to the bearing capacity of the soft soil layer, improve the bearing capacity of the piles, reduce the displacement of the piles, and determine the position of the piles.

[0003] However, when constructing steel casings for composite piles in aquatic environments, due to the difficulty of construction, the problem of reliable connection often occurs. According to research, if the connection between composite piles is unreliable, a sharp axial force mutation will occur at the connection, and the pile-soil interaction will be obvious, which is easy to cause the inclination of the pile connection; in deep water environments, the influence of horizontal loads such as water flow and earthquakes has a greater impact on pile foundations with smaller cross-sections, and the pile body part in the soft soil layer is difficult to fully exert the bearing effect; considering the rise of the weak slurry layer with poor quality on the top of the underwater concrete, especially when the cross-sectional diameter of the pile hole changes, there will be a situation that is unfavorable to the control of concrete quality, and the concrete quality in a certain range around the pile is poor; for the safety and stability of composite pile groups in aquatic environments, it is also necessary to establish an adjustable control system to deal with sudden changes in loads such as water flow in complex environments, so as to control the safety of composite pile group structures in aquatic environments.

[0004] Therefore, it is necessary to design an underwater composite pile that can be prefabricated and assembled on the ground, easy to position underwater, improve the quality of bored piles, increase the horizontal bearing capacity of the pile body, strengthen soft soil layers, and set up an adjustable control system to solve the above technical problems. Summary of the invention

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a combined group pile control system and method of steel casing-steel pipe piles in a water environment. By establishing an underwater group pile structure and its control system, the soft soil layer of the pile body can be reinforced while improving the quality of pile formation, and the pile body can be further reinforced to improve the flexibility and reliability of the device; it can solve the problems of accurate and reliable connection and water flow and earthquake horizontal loads described in the background technology.

[0006] In order to achieve the above-mentioned object, one aspect of the present invention provides a combined pile group control system of steel casing-steel pipe piles in a water environment, wherein the combined pile group comprises a steel casing, a steel track assembly arranged on the outer wall of the steel casing, and a combined steel rod truss connected to the steel track assembly; wherein:

[0007] The steel rail assembly comprises a plurality of vertical steel rails evenly spaced and vertically arranged on the outer wall of the steel casing, and a horizontal steel rail arranged at the bottom of the vertical steel rails and horizontally arranged along the circumference of the outer wall of the steel casing; the combined steel rod truss comprises a plurality of steel rod truss units including steel rod stoppers, steel rods and steel pile stoppers; grouting pipes are respectively arranged on the steel casing and the steel piles;

[0008] The combined pile group control system includes an axial force strain gauge arranged on some steel rods, an underwater controllable jack arranged at the bottom of the steel rod limiter on the vertical steel track, and a ground management system connected to the axial force strain gauge; the axial force change of the pile group structure during actual operation is measured by the axial force strain gauge, and the signal is output to the ground management system; the position of the steel rod limiter is adjusted by the underwater controllable jack, so that the axial force of the overall truss structure is evenly distributed within a limited range, thereby realizing real-time monitoring and adjustment of the stability of the combined pile group.

[0009] Furthermore, the inner diameter of the steel casing is 300-400 mm larger than the design diameter of the bored pile; the bottom elevation of the steel casing is lower than the top surface of the riverbed and enters the impermeable layer.

[0010] Furthermore, the center of the vertical steel rail coincides with the center plane of the steel casing; the upper end of the vertical steel rail is located at the upper edge of the steel casing, and the lower end is located at the lower middle part of the steel casing, and the height from the bottom of the steel casing is higher than the thickness of the soft soil layer.

[0011] Further, the steel bar truss units are adapted to the number of the vertical steel rails;

[0012] The steel rod stoppers are respectively arranged on the vertical steel rail and the horizontal steel rail; each steel rod stopper is connected to the steel pile stopper by a steel rod; the steel pile stopper and the steel rod stopper arranged on the horizontal steel rail are located in the same horizontal plane; the steel rod stoppers are respectively arranged at the bottom and the middle of the vertical steel rail;

[0013] The steel rod limiter and the steel track assembly are combined and fixed by adopting a plum blossom splicing structure.

[0014] Furthermore, the two ends of the steel rod are respectively connected to a steel rod limiter and a steel pile limiter; and the two ends of the steel rod are spherical.

[0015] Furthermore, the steel pile stopper comprises a stopper block connected to the steel rod and a steel sleeve arranged on the side of the stopper block and adapted to the outer diameter of the steel pile;

[0016] The limiting block is provided with a circular hole fixed to the end of the steel rod on a rectangular cross section according to the different directions of the steel rod.

[0017] Furthermore, the steel pile is a prefabricated hollow steel pile with a conical tip at the bottom, which is vertically installed and fixed on the steel sleeve of the steel pile limiter;

[0018] A plurality of rows of circular holes are symmetrically provided within the lower 1 / 2 of the steel pile;

[0019] A movable rubber sealing plug is arranged inside the steel pile; a second grouting pipe on the lower side of the steel pile passes through the rubber sealing plug to the inside of the steel pile and is fixed to the lower side.

[0020] Furthermore, the grouting pipe is a steel circular pipe with a conical tip at the bottom end; the grouting pipe is a steel circular pipe with a conical tip at the bottom end; cement slurry is sprayed into the soft soil layer under the riverbed between the steel casing and the bored piles through the first grouting pipe on the lower side of the inner wall of the steel casing for reinforcement; the second grouting pipe passes through the rubber sealing plug and sprays cement slurry into the soft soil layer around the pile body through the flower-eye circular hole on the lower side of the steel pile for reinforcement, and after the spraying is completed, cement slurry is continuously filled into the steel pile to the designed elevation of the pile top; water is isolated from entering the interior of the steel pile by the rubber sealing plug, and as the steel pile is filled with cement slurry, the rubber sealing plug gradually moves to the top of the steel pile.

[0021] Furthermore, 2 to 4 axial force strain gauges are arranged at different positions; the axial force difference range of each horizontally arranged steel rod is within 30%, and the pile group structure is regarded as being uniformly stressed.

[0022] A second aspect of the present invention provides a construction method of a combined pile group control system of steel casing-steel pipe piles in a water environment, which is implemented by using the combined pile group control system of steel casing-steel pipe piles in a water environment, and comprises the following steps:

[0023] S1: Assembly of various components of the combined pile group control system of steel casing-steel pipe piles in aquatic environment;

[0024] S2: Locate at the construction site to ensure the accurate position of the steel casing; drive the steel casing into the mud surface of the riverbed in sections to the predetermined elevation; pump the prepared mud into the steel casing to ensure that the mud level inside the steel casing is higher than the level outside the casing;

[0025] S3: driving the steel pile according to the position of the preset steel pile stopper;

[0026] S4: Drilling is carried out under the protection of steel casing, and the concrete conduit is hoisted after the hole is cleaned;

[0027] S5: pouring underwater concrete in the concrete conduit in batches until the top design elevation of the steel casing is reached, completing the construction of bored piles;

[0028] S6: injecting cement slurry through the first grouting pipe on the inner wall of the steel casing to reinforce the soft soil layer under the riverbed between the steel casing and the bored piles;

[0029] S7: Use the second grouting pipe on the inner wall of the steel pile to spray cement slurry through the circular hole to reinforce the soft soil layer around the steel pile; after the second grouting pipe sprays cement slurry, fill the steel pile with cement slurry to the pile top until the designed elevation of the steel pile is reached, completing the construction of the underwater steel casing-steel pipe pile group structure with integrated steel casing, steel pile and bored pile;

[0030] S8: Measure the axial force changes of the combined pile group structure of underwater steel casing-steel pipe piles during actual operation through the steel rod axial force strain gauge, and output the signal to the ground management system; adjust the position of the steel rod limiter through the underwater controllable jack, so that each steel rod top support combined structure is in place, and the axial force of the overall truss structure is evenly distributed to a limited range, so as to realize real-time monitoring and adjustment of the stability of the combined pile group structure.

[0031] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0032] (1) Compared with the traditional composite piles, the composite pile group control system of steel casing-steel pipe piles in the water environment of the present invention can weld and set steel rod limiters, steel rods and steel pile limiters on the steel casing in the ground environment, and then sink them into place together with the steel casing after the truss structure is set. It is simple to operate and convenient to construct, and can solve the problem of unreliable connection of traditional composite piles.

[0033] (2) The combined pile group control system of steel casing-steel pipe piles in aquatic environments of the present invention not only provides expandable steel pile support for traditional combined piles, improves the overall stiffness of steel casings, and changes the cross-sectional mutation of "large and small piles" directly connected to each other in traditional combined piles by welding steel rails on steel casings, setting steel rod limiters and steel pile limiters, and using steel rods for connection; the traditional cast-in-place piles and the surrounding steel piles are connected by a truss of steel rod limiters, steel rods, and steel pile limiters, so that the force transmission paths for coping with horizontal and vertical loads are diversified, thereby improving the stress condition of the pile body; the surrounding pile group itself is also a protective structure and guide structure for pile holes, and forms a structure similar to a "pile group" with the steel casing, further improving the stiffness of the piles. Compared with traditional bored cast-in-place piles, the combined pile group structure of steel casing-steel pipe piles provided by the present invention has greater bearing capacity and stiffness.

[0034] (3) The combined pile group control system of steel casing-steel pipe piles in aquatic environment of the present invention measures the axial force changes of the pile group structure during actual operation through the steel rod axial force strain gauge, controls the steel rod strain information in real time, and controls the axial force difference range of each horizontal steel rod within 30% to ensure that the pile group structure is uniformly stressed; if the difference exceeds the control range, the jack is operated and regulated by a pump machine on the ground through an oil pipe to adjust the steel rod truss structure, so that the steel rods of each part of the combined steel rod truss are pulled or the original pressure value becomes smaller, so that the axial force of the overall truss structure is redistributed evenly, thereby effectively controlling the reasonable sharing of loads in all directions when the structural combination of steel casing-steel pipe piles is working, and giving full play to the structural bearing capacity.

[0035] (4) The combined pile control system of steel casing and steel pipe pile in the water environment of the present invention has grouting pipes installed on the lower side of the inner wall of the steel casing and the steel pile respectively. After the bored pile is cast, cement slurry is injected into the steel casing and the steel pile respectively to reinforce the soil, and cement slurry is filled into the steel pile to the pile top. The traditional bored pile does not have a reasonable process system to deal with this weak interlayer soil during construction. The present invention uses a first grouting pipe arranged on the inner wall of the steel casing to inject grout into the weak soil layer under the riverbed between the steel casing and the bored pile, and a second grouting pipe arranged on the inner wall of the steel pile to spray cement slurry into the weak soil layer around the steel pile for reinforcement. This not only reinforces the soil between the bored pile and the steel pipe pile and improves the mechanical properties of the soil itself, but also improves the integrity of this part of the soil and the bored pile, thereby further improving the lateral bearing capacity of the pile body.

[0036] (5) The underwater composite pile group structure of steel casing-steel pipe piles of the present invention can effectively improve the bearing capacity of the piles and reduce the displacement of the piles, which is crucial for the stability of structures in water conservancy projects, such as sluice gates, dams, etc.; soft soil layers are often encountered in water conservancy projects, and the underwater composite pile structure can give full play to the bearing capacity of the soft soil layers and improve the stability and safety of the pile foundation; the underwater composite pile structure can be prefabricated and assembled on the ground, and is easy to position underwater, which can improve the construction efficiency and safety of underwater construction in water conservancy projects; the application of underwater concrete in bored pile construction can improve project quality, reduce costs, and improve construction efficiency, which is of great significance to the quality and economic benefits of water conservancy projects. There is a direct impact; water conservancy projects need to consider the impact of extreme loads such as earthquakes and water scouring. The underwater composite pile structure can improve the horizontal bearing capacity of the pile body and effectively cope with these loads; water conservancy projects need to establish an adjustable control system to deal with sudden changes in loads such as water flow in complex environments. The adjustable control system in the underwater composite pile structure can control the safety of the composite pile group structure in the water environment, which is crucial to the safe operation of water conservancy projects; in summary, the application of underwater composite pile structures in water conservancy projects can not only improve the bearing capacity and stability of the structure, but also improve construction efficiency and project quality. At the same time, it plays an important role in protecting the water environment and ensuring the safe operation of water conservancy projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0038] Figure 2 A schematic diagram of a side view structure and grouting area of ​​a combined pile group control system of steel casing-steel pipe piles arranged underwater in a water environment according to an embodiment of the present invention;

[0039] Figure 3 A schematic diagram of a steel pile grouting section AA in a side view of an underwater arrangement of a combined pile group control system of a steel casing-steel pipe pile in a water environment according to an embodiment of the present invention;

[0040] Figure 4 A schematic diagram of a steel casing grouting section BB in a side view of an underwater arrangement of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0041] Figure 5 It is a schematic diagram of a top view of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0042] Figure 6 A schematic diagram of the structure of steel piles in a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of the installation structure of a second grouting pipe and a rubber sealing plug inside a steel pile of a combined pile group control system of a steel casing-steel pipe pile in a water environment according to an embodiment of the present invention;

[0044] Figure 8 A schematic diagram of the installation position of a steel rod limiter of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0045] Fig. 9 It is a structural schematic diagram of a steel pile limiter of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0046] Fig.10 It is a schematic diagram of the arrangement of rectangular surface circular holes of a steel pile stopper of a combined pile group control system of a steel casing-steel pipe pile in a water environment according to an embodiment of the present invention;

[0047] Fig.11 It is a schematic structural diagram of steel rods of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0048] Fig.12It is a schematic diagram of the exploded structure of a vertical steel rod stopper and a first horizontal steel rod stopper of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0049] Fig.13 It is a schematic diagram of the exploded structure of a second horizontal steel rod stopper and a third horizontal steel rod stopper in a common position of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention;

[0050] Fig.14 The present invention is a flowchart of a construction method of a combined pile group control system of steel casing-steel pipe piles in a water environment according to an embodiment of the present invention.

[0051] In all the drawings, the same figure marks represent the same technical features, specifically: 1-steel casing, 2-steel rail assembly, 21-vertical steel rail, 22-horizontal steel rail, 3-steel rod limiter, 30-vertical steel rod limiter, 31-first horizontal steel rod limiter, 32-second horizontal steel rod limiter, 33-third horizontal steel rod limiter, 4-steel rod, 41-inclined steel rod, 42-horizontal steel rod, 5-steel pile limiter, 51-limiting block, 511-round hole, 52-steel sleeve, 6-steel pile, 71-first grouting pipe, 72-second grouting pipe, 8-bored pile, 9-eye round hole, 10-underwater controllable jack, 11-axial force strain gauge, 12-rubber sealing plug. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0053] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, when an element is referred to as being "fixed to", "disposed on" or "provided on" another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element; the terms "installed", "connected", "connected" and "provided with" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal connection of the two elements or the interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0054] In addition, the terms "first", "second", etc. 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" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0055] like Figure 1-Figure 13As shown, one aspect of the present invention provides a combined pile group control system of steel casing-steel pipe piles in a water environment, which is suitable for a water environment. The combined pile group of steel casing-steel piles includes a steel casing 1 for ensuring the construction position of a bored pile 8, a steel track assembly 2 arranged on the outer wall of the steel casing 1, and a combined steel rod truss connected to the steel track assembly 2; the steel track assembly 2 includes a plurality of vertical steel rails 21 evenly spaced vertically arranged on the outer wall of the steel casing 1 and a horizontal steel rail 22 arranged at the bottom of the vertical steel rail 21 and horizontally arranged along the circumference of the outer wall of the steel casing 1; the combined steel rod truss includes a plurality of vertical steel rails 21 that are suitable in number for the vertical steel rails 21 The invention discloses a plurality of steel bar truss units including steel bar limiters 3, steel bars 4 and steel pile limiters 5; the steel bar limiters 3 are respectively arranged on the vertical steel rail 21 and the horizontal steel rail 22; each steel bar limiter 3 is connected to the steel pile limiter 5 through the steel bar 4; the steel pile limiter 5 and the steel bar limiter 3 arranged on the horizontal steel rail 22 are located in the same horizontal plane, and the two are connected through the horizontally arranged steel bar 4; the steel pile limiter 5 and the steel bar limiter 3 arranged on the vertical steel rail 21 are connected through the inclined steel bar 4; the steel pile 6 is driven vertically into the ground along the side of the steel pile limiter 5 away from the steel bar 4; the inner wall of the steel casing 1 and the steel pile 6 are respectively provided with There is a grouting pipe; the combined pile group control system includes an axial force strain gauge 11 arranged in the middle of the horizontally arranged steel rod 4, an underwater controllable jack 10 arranged at the bottom of the steel rod limiter 3 on the vertical steel track 21, and a ground management system arranged on the ground and connected to the axial force strain gauge 11; the axial force change of the pile group structure during actual operation is measured by the steel rod axial force strain gauge 11, and the signal is output to the ground management system; the difference range between the axial forces measured by the axial force strain gauges 11 on each horizontally arranged steel rod 4 is controlled within 30%, and the combined pile group structure connected by the overall steel rod truss is considered to be in a stable state; if the difference exceeds the control range, The underwater controllable jack 10 is operated on the ground through an oil pipe using a pump to adjust the position of the steel rod limiter 3, so that the steel rods of each part of the combined steel rod truss are pulled or the original pressure value becomes smaller, so that the axial force distribution of the overall truss structure is uniform within a limited range, and real-time monitoring and adjustment of the stability of the combined pile group structure is achieved, thereby effectively controlling the effectiveness of the actual combination work of the steel casing-steel pile group structure; the present invention can be prefabricated and assembled on the ground, conveniently positioned underwater, improve the quality of bored piles, and improve the horizontal bearing capacity of the pile body. An adjustable control system is also provided to solve the safety and stability problems of the combined pile groups in aquatic environments.

[0056] Furthermore, if Figure 1-Figure 13As shown, the inner diameter of the steel casing 1 is 300-400mm larger than the design diameter of the bored pile 8; for small-diameter bored piles, the wall thickness of the steel casing is 1 / 150-1 / 100 of its diameter, and for large-diameter extra-long bored piles, the wall thickness of the steel casing is 15-25mm, so as to ensure that the steel casing 1 does not deform during the construction process; at the same time, it should be noted that the thickness of the steel casing 1 is closely related to the diameter of the steel casing 1, the depth of burial, etc., so the thickness selection of the steel casing 1 needs to be closely related to the actual situation of the project; the center of the steel casing 1 and the center plane position deviation of the bored pile 8 are not more than 50mm, so as to ensure the positioning and anti-deviating effect. The top elevation of the steel casing 1 is 1-2m higher than the maximum water level to prevent surface water from entering the borehole; the bottom elevation of the steel casing 1 is lower than the top surface of the riverbed, and is driven into a soil layer with higher bearing capacity and lower permeability, so that the structure is stable and mud loss is prevented.

[0057] Furthermore, if Figure 1-Figure 13 As shown, the steel track assembly 2 is welded to the outer wall of the steel casing 1, and the steel track assembly 2 is made of steel bars with a thickness of 20 to 40 mm; a steel rod limiter 3 is arranged on the steel track assembly 2 so that it can slide on the steel track assembly 2; the center of the vertical steel track 21 coincides with the center plane of the steel casing 1, its upper end is located at the upper edge of the steel casing 1, and the lower end is located at the middle and lower part of the steel casing 1, and the height from the bottom of the steel casing 1 is higher than the thickness of the soft soil layer; the horizontal steel track 22 is arranged at the bottom of the vertical steel track 21 and surrounds the steel casing 1; the steel track assembly 2 plays the role of fixing the position of the steel rod limiter 3, transferring load The steel rail assembly 2 forms a steel rod truss structure of steel casing-steel pile with the steel casing 1 and the steel pile 6 through the steel rod stopper 3, the steel rod 4 and the steel pile stopper 5, thereby determining the driving position of the steel pile 6; the combined truss structure can effectively eliminate the characteristics of the pile body being easily affected by water flow in the soft soil layer and having insufficient horizontal bearing capacity; the steel rod truss structure makes the load transfer path diverse, effectively improving the stability of the overall combined structure; when pouring cast-in-place pile concrete, it can also avoid the abnormality of the soft layer on the top of the underwater concrete at the cross-section change.

[0058] Furthermore, if Figure 1-Figure 13As shown, each steel bar truss unit includes a vertical steel bar stopper 30 arranged in the middle of the vertical steel rail 21, a first horizontal steel bar stopper 31 arranged at the bottom of the vertical steel rail 21, a second horizontal steel bar stopper 32 and a third horizontal steel bar stopper 33 respectively arranged on the horizontal steel rail 22 and located on both sides of the vertical steel rail 21, and a steel pile stopper 5 connected to the vertical steel bar stopper 30, the first horizontal steel bar stopper 31, the second horizontal steel bar stopper 32 and the third horizontal steel bar stopper 33; the first horizontal steel bar stopper 31 is also arranged on the horizontal steel rail 22. On the flat steel rail 22; the steel pile stopper 5 and the three horizontal steel rod stoppers are located in the same horizontal plane; two adjacent steel rod truss units share a horizontal steel rod stopper; the steel pile stopper 5 and each steel rod stopper 3 are connected through a steel rod 4; specifically, the first horizontal steel rod stopper 31, the second horizontal steel rod stopper 32 and the third horizontal steel rod stopper 33 are connected to the steel pile stopper 5 through a horizontal steel rod 42 respectively; the vertical steel rod stopper 30 is connected to the steel pile stopper 5 through an inclined steel rod 41; the vertical steel rod stopper 30 and the first horizontal steel rod stopper 31 are Fig.12 The second horizontal steel rod stopper 32 and the third horizontal steel rod stopper 33 are Fig.13 Steel rod stop shown.

[0059] Furthermore, if Figure 1-Figure 13 As shown, the steel rod limiter 3 can be fixed on the steel track assembly 2 at the bottom and middle of the vertical steel track 21, evenly distributed on the horizontal steel track 22, and driven into the riverbed together with the steel casing 1; the steel rod limiter 3 and the steel track assembly 2 are fixed in combination with a plum blossom splicing structure, the diameter of the middle circular hole is 20 to 50 mm, and the preferred size of the rectangular side length of the cross-section is 60 to 120 mm; this structure ensures the integrity of the structure with the main bored pile 8, and provides a guarantee for the fixation of the steel rod 4 and the further fixation of the position of the steel pile 6.

[0060] Furthermore, if Figure 1-Figure 13 As shown, the two ends of the steel rod 4 are respectively connected to the steel rod limiter 3 and the steel pile limiter 5; the diameter of the steel rod 4 is preferably 50-80 mm, and the two ends of the steel rod 4 are spherical connection sections, and the diameter is preferably 70-100 mm.

[0061] Furthermore, if Figure 1-Figure 13As shown, the steel pile stopper 5 comprises a stopper block 51 connected to the steel rod 4 and a steel sleeve 52 arranged on the side of the stopper block 51 and adapted to the outer diameter of the steel pile 6; the steel sleeve 52 is used to fix the driven steel pile 6, the steel sleeve 52 is about 100mm to 200mm high, and the preferred diameter is slightly larger than the diameter of the steel pile 6 by 2 to 5mm; the steel pile 6 is driven along the center of the steel sleeve 52; the side of the stopper block 51 close to the steel rod 4 is a rectangular surface, and the side close to the steel sleeve 52 is an arc surface; according to the number and direction of the steel rods 4, The rectangular surface is provided with a plurality of circular holes 511 matching the end spherical connecting section of the steel rod 4; the circular holes 511 are distributed in two layers, upper and lower, on the rectangular surface; the upper holes are used to connect with the inclined steel rod 41; the lower holes are used to connect with the horizontal steel rod 42; the diameter of the circular holes 511 is 20 to 50 mm, and the side length of the rectangular surface is preferably 60 to 120 mm; the overall combined steel rod truss can effectively ensure the stability of the connection of the driven steel piles 6, so that the steel piles 6 can effectively play the role of horizontal bearing capacity and improve the stability of the overall combined structure.

[0062] Furthermore, if Figure 1-Figure 13 As shown, the steel pile 6 is a prefabricated hollow steel pile with a conical tip at the bottom, which is vertically installed and fixed on the steel sleeve 52 of the steel pile stopper 5; the diameter of the steel pile 6 is 20-50 mm; it is driven into the riverbed according to the position of the steel pile stopper 5, and its top elevation is higher than the steel casing 1, and the bottom elevation is located between the soft soil layers under the mud surface; multiple rows (preferably 4 rows) of symmetrical eye holes 9 are opened in the lower 1 / 2 range of the steel pile 6, and the eye holes 9 have a diameter of 5-8 mm and a spacing of 15 cm. Cement slurry passes through the eye holes 9 to achieve the effect of large-area grouting reinforcement of the soft interlayer; the eye holes 9 are inserted into the soil when the steel pile 6 is inserted The steel pile 6 is sealed with tape before use to prevent blockage. After being inserted into the soil, the tape will be washed away as cement slurry is poured in, thereby reinforcing the soft soil layer around the steel pile 6. A movable rubber sealing plug 12 is arranged inside the steel pile 6. The second grouting pipe 72 inside the steel pile 6 passes through the rubber sealing plug 12 and is fixed to the lower side of the steel pile 6, and the rubber sealing plug 12 is used to isolate the outside water from entering the steel pile 6. After the steel pile 6 is driven into place along the steel pile limiter 5, cement slurry is injected through the first grouting pipe 71 on the inner wall of the steel casing 1 to reinforce the soft soil between the lower part of the steel casing 1 and the bored pile 8 and around the steel pile 6, thereby improving the stability of the soil layer.

[0063] Furthermore, if Figure 1-Figure 13As shown, the grouting pipe is a steel round pipe with a conical tip at the bottom, which is convenient for driving into the soil; the first grouting pipe 71 has a diameter of 20-60 mm, is closely attached to the inner wall of the steel casing 1, and is driven into the riverbed together with the steel casing 1, and its top elevation is higher than the steel casing 1, and the bottom elevation is located between the soft soil layers under the mud surface; the second grouting pipe 72 has a diameter of 20-60 mm, is fixed on the inner wall of the steel pile 6, and is driven into the soil layer together with the steel pile 6. After the bored pile 8 is cast, cement slurry is injected into the steel casing 1 and the steel pile 6 through the first grouting pipe 71 and the second grouting pipe 72 respectively to reinforce part of the soil.

[0064] Furthermore, if Figure 1-Figure 13 As shown, 2 to 4 axial force strain gauges 11 can be arranged at different positions. The axial force change of the pile group structure during actual operation is measured according to the axial force strain gauges 11 on the horizontally arranged steel rods 4, and the strain information of the horizontally arranged steel rods 4 is controlled in real time. The signal is output to the ground management system, and the axial force difference range of each horizontally arranged steel rod 4 is statistically analyzed to see whether it is within 30% to ensure that the pile group structure is uniformly stressed. If the difference exceeds the control range, the underwater controllable jack 10 is operated and regulated by a pump machine through an oil pipe on the ground to adjust the steel rod truss structure, so that the steel rods of each part of the combined steel rod truss are pulled or the original pressure value becomes smaller, so that the axial force of the overall truss structure is evenly redistributed, thereby effectively controlling the reasonable sharing of directional loads when the steel casing-steel pile structure combination works, and giving full play to the structural bearing capacity.

[0065] like Fig.14 As shown, the second aspect of the present invention provides a construction method of a combined pile group control system of steel casing-steel pipe piles in a water environment, comprising the following steps:

[0066] S1: Assembly of a combined pile group control system of steel casing-steel pipe piles in aquatic environments; prefabricate a steel casing 1 on the ground, design and install a steel track 2, a steel rod stopper 3, a steel rod 4, and a steel pile stopper 5 according to construction requirements, and weld them to form a steel rod truss structure; install grouting pipes on the inner walls of the steel casing 1 and the steel pile 6 respectively; install an underwater controllable jack 10 below the steel rod stopper 3 of the vertical steel track 21, and install an axial force strain gauge 11 in the middle of the horizontal steel rod 4; connect the axial force strain gauge 11 to the ground information management system for communication;

[0067] Specifically, the dimensions and specifications of components such as steel casings, steel tracks, steel rod trusses, and steel piles are designed according to the project requirements; the required construction materials and equipment, including steel casings, steel tracks, steel rods, steel pile limiters, grouting pipes, axial force strain gauges, underwater controllable jacks, and ground management systems, are prepared; a steel casing 1 is prefabricated on the ground, a steel track component 2 is installed on the steel casing 1 according to the design of the construction requirements, a steel rod limiter 3 is installed on the steel track component 2, a steel rod 4 is connected to the steel rod limiter 3, and a steel rod 4 is installed on the steel rod The other end of 4 is connected to the steel pile stopper 5 to form a combined steel rod truss structure; the first grouting pipe 71 is set on the lower side of the inner wall of the steel casing 1; the second grouting pipe 72 passes through the movable rubber sealing plug 12 inside the steel pile 6 and is set on the lower side of the inner wall of the steel pile 6 to prepare for subsequent grouting reinforcement; an underwater controllable jack 10 is installed below the steel rod stopper 3 of the vertical steel track 21, and an axial force strain gauge 11 is installed in the middle of the horizontal steel rod 4; the axial force strain gauge 11 is connected to the ground information management system for communication;

[0068] S2: Stake out at the construction site to determine the correct position of the steel casing 1; drive the steel casing 1 into the mud surface of the riverbed in sections to a predetermined elevation; pump the prepared mud into the steel casing 1 to ensure that the mud level inside the steel casing 1 is higher than the level outside the casing;

[0069] S3: driving the steel pile 6 according to the preset position of the steel pile stopper 5;

[0070] Specifically, the steel pile 6 is driven vertically into the ground along the steel sleeve 52 of the steel pile stopper 5, ensuring that the top elevation of the steel pile 6 is higher than the steel casing 1, and the bottom elevation is located between the soft soil layers under the mud surface;

[0071] S4: drilling a hole under the protection of the steel casing 1, and hoisting the concrete conduit after cleaning the hole;

[0072] Specifically, under the protection of the steel casing 1, a drilling rig is lowered at the center point of the lower tube of the steel casing 1 to drill a hole, and mud circulation is continuously performed during the process, thereby removing drilling debris and mud wall protection. After the drilling is completed, the hole is cleaned and the concrete pipe is hoisted;

[0073] S5: pouring underwater concrete in the concrete conduit in batches until the top design elevation of the steel casing 1 is reached, completing the construction of the bored pile 8;

[0074] S6: Cement slurry is injected into the soft soil layer under the riverbed between the steel casing 1 and the bored pile 8 through the first grouting pipe 71 on the inner wall of the steel casing 1 for reinforcement ( Figure 2 Middle C is the grouting area of ​​the second grouting pipe; Figure 4 F in the middle is the soft soil layer between the bored piles and the steel casing reinforced with cement slurry);

[0075] S7: The second grouting pipe 72 on the inner wall of the steel pile 6 is used to inject cement slurry through the circular hole 9 to reinforce the soft soil layer around the steel pile 6 ( Figure 2 D in the middle is the grouting area of ​​the first grouting pipe; Figure 3 E is the soft soil layer around the steel pile reinforced with cement slurry); after the second grouting pipe 72 is sprayed with cement slurry, the cement slurry is filled into the steel pile 6 to the pile top until the designed elevation of the steel pile 6 is reached, completing the construction of the underwater steel casing-steel pipe pile group structure of the integrated steel casing 1, steel pile 6, and bored pile 8;

[0076] Specifically, underwater concrete is poured in batches until it reaches the top surface of the riverbed, and concrete is poured upwards so that the steel casing 1 is filled with cast-in-place concrete until the designed elevation of the bored pile 8 is reached; concrete is poured into the steel pile 6 to the pile top until the designed elevation of the steel pile 6 is reached, thereby realizing an underwater steel casing-steel pipe pile combined pile group structure integrating the steel casing 1, the steel pile 6, and the bored pile 8;

[0077] S8: Measure the axial force change of the combined pile group structure of the underwater steel casing-steel pipe pile during actual operation through the steel rod axial force strain gauge 11, and output the signal to the ground management system; adjust the 3 positions of the steel rod limiter through the underwater controllable jack 10, so that each steel rod 4 supports the combined structure in place, and the axial force of the overall truss structure is evenly distributed within a limited range, so as to realize real-time monitoring and adjustment of the stability of the combined pile group structure;

[0078] Specifically, the axial force change of the combined pile group structure of the underwater steel casing-steel pipe pile during actual operation is measured by the steel rod axial force strain gauge 11, and the strain information of the steel rod 4 is controlled in real time, and the axial force difference range measured by each horizontal steel rod 4 is controlled within 30% to ensure that the pile group structure is uniformly stressed; if the difference exceeds the control range, the underwater controllable jack 10 is operated and regulated by the pump machine through the oil pipe on the ground to adjust the steel rod truss structure, so that the steel rods 4 of each part of the combined steel rod truss are pulled or the original pressure value is reduced, so that the axial force of the overall truss structure is evenly redistributed, thereby effectively controlling the reasonable sharing of the loads in all directions when the structural combination of the steel casing-steel pipe pile works, and giving full play to the structural bearing capacity. The completed combined pile group structure is quality inspected to ensure that it meets the design requirements.

[0079] The steel casing of the present invention is used as the main protective structure, which is driven into the riverbed mud surface to a certain depth, and the top elevation is higher than the horizontal plane, so as to ensure the construction position of the bored pile and prevent water from entering the drill hole; the steel rail is welded to the inner wall of the steel casing, and is used to fix the steel rod limiter and the steel pile limiter to transfer the load; the steel rod limiter is fixed on the steel rail, and is used to determine the position of the steel rod; the steel rod connects the steel rod limiter and the steel pipe limiter to form a truss structure, and improves the overall rigidity; the steel pile limiter is used to determine the driving position of the steel pile; the steel pile is a prefabricated hollow steel pile, and the bottom is a conical tip, which is used to improve the horizontal bearing capacity; the grouting pipe is used to Inject cement slurry into the steel casing and steel piles to reinforce the soil; underwater controllable jacks are used to adjust the steel rod truss structure to ensure uniform axial force distribution; axial force strain gauges are used to measure the axial force changes of the steel rods and monitor the stability of the structure in real time; through ground prefabrication and assembly, the complexity of underwater construction is simplified; through the combined use of steel casings and steel piles, the bearing capacity and stiffness of the piles are improved; through truss structures and grouting reinforcement, the overall stability of the structure is enhanced; through the control system of axial force strain gauges and jacks, the stability of the combined pile group structure of steel casing-steel piles is monitored and adjusted in real time. The present invention welds steel rails on steel casings and sets steel rod limiters and steel pile limiters, which is simple to construct and solves the problem of difficult installation in water environments; using steel rods for connection not only provides expansive steel pile support at the place where the pile body diameter changes, but also improves the overall stiffness of the steel casing, and changes the cross-sectional mutation of the traditional variable cross-section piles "large and small piles" directly connected, thereby improving the stress condition of the pile body. Therefore, the surrounding pile group itself is also the surrounding structure and guide structure of the pile hole, and forms a structure similar to a "pile group" with the steel casing, further improving the horizontal stiffness of the pile. Compared with traditional bored piles, the combined pile group structure of steel casing-steel pipe piles provided by the present invention has greater horizontal bearing capacity and stiffness.

[0080] According to existing research, the properties of the surface soil of traditional bored piles are generally poor, the stiffness of the pile is much greater than the stiffness of the soil layer, and the horizontal resistance of the soil around the pile is low. In aquatic environments, the entire pile body is prone to tilting under horizontal loads such as water flow and earthquakes. The calculation formula for the horizontal bearing capacity of the pile can be calculated as follows:

[0081] (1)

[0082] Where:

[0083] represents the characteristic value of the horizontal bearing capacity of the pile; represents the horizontal deformation coefficient of the pile; According to the nature of the vertical force at the top of the pile, the pressure is "+" and the tension is "-"; is the plasticity coefficient of pile section modulus; is the design value of the tensile strength of the pile concrete; is the maximum bending moment coefficient of the pile; is the reinforcement ratio of the pile body; is the influence coefficient of the vertical force of the pile; is the vertical force at the pile top under the standard combination of load effects; The elastic resistance moment of the tensile edge of the converted section of the pile body; Converted cross-sectional area of ​​the pile body.

[0084] It can be seen from formula (1) that compared with the equal-section piles of the same length and diameter equal to the pile top diameter, the combined pile group system of steel casing-steel pipe piles has a larger cross-section and reinforces the soil around the piles, with a higher horizontal bearing capacity. In the formula, the elastic resistance moment of the tensile edge of the pile conversion section is The theoretical horizontal bearing capacity characteristic value is improved accordingly. Therefore, the combined pile group of steel casing-steel pipe piles of the present invention has a higher bearing capacity and can improve the horizontal stress of the pile body; the weak soil at the lower part of the variable cross-section is reinforced by the use of the grouting pipe, so that it can provide a greater bearing capacity.

[0085] The present invention measures the axial force change of the pile group structure during actual operation through the axial force strain gauge 11, and outputs the signal into the ground information management system. If the difference range between the axial forces is controlled within 30%, it means that the steel rods of the overall truss structure are evenly stressed, the connection between the surrounding steel piles and the steel casing is reliable, and they share the load, so the bearing capacity of the combined structure can be effectively exerted; if the difference exceeds the control range, the ground uses a pump to operate and control the jack through the oil pipe, adjusts the position of the steel rod limiter, and adjusts the position of the steel pile limiter through the top support, so that the connected horizontal steel rods are reliably connected, so that the steel rods of each part of the combined steel rod truss are pulled or the original pressure value is reduced, so that the axial force distribution of the overall truss structure is evenly distributed within the limited range, and the stability and effectiveness of the combined pile group structure are fully realized.

[0086] It will be easily understood by those skilled in the art that 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 combined pile group control system of steel casing and steel pipe piles in a water environment, characterized by: The combined pile group comprises a steel casing (1), a steel track assembly (2) arranged on the outer wall of the steel casing (1), and a combined steel rod truss connected to the steel track assembly (2); wherein: The steel rail assembly (2) comprises a plurality of vertical steel rails (21) evenly spaced and vertically arranged on the outer wall of the steel casing (1) and a horizontal steel rail (22) arranged at the bottom of the vertical steel rail (21) and horizontally arranged along the circumference of the outer wall of the steel casing (1); the combined steel rod truss comprises a plurality of steel rod truss units simultaneously comprising steel rod stoppers (3), steel rods (4) and steel pile stoppers (5); the steel rod stoppers (3) are respectively arranged on the vertical steel rails (21) and the horizontal steel rails (22); each steel rod stopper (3) and the steel pile stopper (5) are connected via the steel rod (4); the steel pile stopper (5) and the steel rod stopper (3) arranged on the horizontal steel rail (22) are located on the same horizontal plane; The steel rod stopper (3) is respectively arranged at the bottom and the middle of the vertical steel rail (21); the two ends of the steel rod (4) are respectively connected to the steel rod stopper (3) and the steel pile stopper (5); the steel pile stopper (5) comprises a stopper block (51) connected to the steel rod (4) and a steel sleeve (52) arranged on the side of the stopper block (51) and adapted to the outer diameter of the steel pile (6); the steel pile (6) is driven vertically into the ground along the steel sleeve (52) of the steel pile stopper (5); and grouting pipes are respectively arranged on the steel casing (1) and the steel pile (6); The combined pile group control system comprises an axial force strain gauge (11) arranged on a portion of the steel rods (4), an underwater controllable jack (10) arranged at the bottom of the steel rod stopper (3) on the vertical steel track (21), and a ground management system connected to the axial force strain gauge (11); the axial force change of the pile group structure during actual operation is measured by the axial force strain gauge (11), and the signal is output to the ground management system; the position of the steel rod stopper (3) is adjusted by the underwater controllable jack (10), so that the axial force of the overall truss structure is evenly distributed within a limited range, thereby achieving real-time monitoring and adjustment of the stability of the combined pile group.

2. The combined pile group control system of steel casing and steel pipe piles in a water environment according to claim 1 is characterized in that: The inner diameter of the steel casing (1) is 300-400 mm larger than the design diameter of the bored pile (8); the bottom elevation of the steel casing (1) is lower than the top surface of the riverbed and enters the impermeable layer.

3. The combined pile group control system of steel casing and steel pipe piles in water environment according to claim 2 is characterized by: The center of the vertical steel track (21) coincides with the center plane of the steel casing (1); the upper end of the vertical steel track (21) is located at the upper edge of the steel casing (1), and the lower end is located at the middle and lower part of the steel casing (1), and the height from the bottom of the steel casing (1) is higher than the thickness of the soft soil layer.

4. A combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 3, characterized in that: The number of the steel bar truss units matches the number of the vertical steel rails (21); The steel rod stopper (3) and the steel track assembly (2) are combined and fixed using a plum blossom splicing structure.

5. A combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 3, characterized in that: Both ends of the steel rod (4) are spherical.

6. A combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 3, characterized in that: The limiting block (51) is provided with a circular hole (511) on a rectangular cross section according to the different directions of the steel rod (4) and fixed to the end of the steel rod (4).

7. A combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 3, characterized in that: The steel pile (6) is a prefabricated hollow steel pile with a conical tip at the bottom, and is vertically mounted and fixed on the steel sleeve (52) of the steel pile stopper (5); A plurality of rows of circular holes (9) are symmetrically provided in the lower 1 / 2 of the steel pile (6); A movable rubber sealing plug (12) is provided on the lower side of the interior of the steel pile (6); a second grouting pipe (72) on the lower side of the interior of the steel pile (6) passes through the rubber sealing plug (12) to the interior of the steel pile (6) and is fixed to the lower side.

8. The combined pile group control system of steel casing and steel pipe piles in water environment according to claim 7, characterized in that: The grouting pipe is a steel round pipe with a conical tip at the bottom. The first grouting pipe (71) on the lower side of the inner wall of the steel casing (1) is used to spray cement slurry into the soft soil layer under the riverbed between the steel casing (1) and the bored pile (8) for reinforcement. The second grouting pipe (72) passes through the rubber sealing plug (12) and sprays cement slurry into the soft soil layer around the pile body through the round hole (9) on the lower side of the steel pile (6) for reinforcement. After the spraying is completed, cement slurry is continuously filled into the steel pile (6) to the designed elevation of the pile top. The rubber sealing plug (12) is used to prevent water from entering the interior of the steel pile (6). As the steel pile (6) is filled with cement slurry, the rubber sealing plug (12) gradually moves to the top of the steel pile (6).

9. A combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 3, characterized in that: The axial force strain gauges (11) are arranged in 2 to 4 pieces at different positions; the axial force difference range of each horizontally arranged steel rod (4) is within 30%, and the pile group structure is regarded as being uniformly stressed.

10. A construction method for a combined pile group control system of steel casing and steel pipe piles in a water environment, characterized in that: The combined pile group control system of steel casing-steel pipe piles in a water environment according to any one of claims 1 to 9 is implemented, comprising the following steps: S1: Assembly of various components of the combined pile group control system of steel casing-steel pipe piles in aquatic environment; S2: Stake out at the construction site to determine the correct position of the steel casing (1); drive the steel casing (1) into the mud surface of the riverbed in sections to a predetermined elevation; pump the prepared mud into the steel casing (1) to ensure that the mud level inside the steel casing (1) is higher than the level outside the casing; S3: driving the steel pile (6) according to the preset position of the steel pile stopper (5); S4: drilling a hole under the protection of the steel casing (1), and hoisting the concrete conduit after cleaning the hole; S5: pouring underwater concrete in batches in the concrete conduit until the top design elevation of the steel casing (1) is reached, thereby completing the construction of the bored piles (8); S6: injecting cement slurry through the first grouting pipe (71) on the inner wall of the steel casing (1) into the soft soil layer under the riverbed between the steel casing (1) and the bored piles (8) for reinforcement; S7: injecting cement slurry through the second grouting pipe (72) on the inner wall of the steel pile (6) through the eyelet circular hole (9) to reinforce the soft soil layer around the steel pile (6); after the second grouting pipe (72) injects cement slurry, the cement slurry is filled into the steel pile (6) to the pile top until the designed elevation of the steel pile (6) is reached, thereby completing the construction of the underwater steel casing-steel pipe pile combined pile group structure integrating the steel casing (1), the steel pile (6) and the bored pile (8); S8: Measure the axial force change of the underwater steel casing-steel pipe pile combined pile group structure during actual operation through the steel rod axial force strain gauge (11), and output the signal to the ground management system; adjust the position of the steel rod limiter (3) through the underwater controllable jack (10), so that each steel rod (4) supports the combined structure in place, and the axial force of the overall truss structure is evenly distributed within a limited range, thereby realizing real-time monitoring and adjustment of the stability of the combined pile group structure.

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