Suspension bridge anchorage split type seabed open caisson foundation construction method and device

Abstract

The invention relates to the technical field of bridge construction, in particular to a suspension bridge anchorage split type seabed open caisson foundation construction method and device. The construction method comprises the steps of foundation pit excavation, concrete replacement and filling, steel open caisson manufacturing, undocking and floating transportation, positioning and sinking, bottom sealing and core filling, sandwich wall concrete pouring, straining beam construction, cover plate construction and gravel backfilling. The concrete replacement filling comprises pouring point arrangement, foundation pouring device erection and underwater concrete pouring; the positioning sinking refers to water injection sinking and rapid high-precision positioning of the open caisson by utilizing an automatic positioning anchor cable device, an automatic positioning control device and an open caisson leveling and supporting device; the straining beam construction step comprises the steps of hanging a straining beam pouring device, floating pouring of straining beam concrete, joint construction of the open caisson and the straining beam pouring device, dry pouring of residual straining beam concrete and dismantling of the straining beam pouring device. The foundation is high in bearing capacity and flatness and good in applicability; the positioning precision of the open caisson is high; the large-span high-water-head-difference reinforced concrete straining beam is short in construction period and low in cost.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a method and a device for constructing a suspension bridge anchored split-type submarine caisson foundation. Background Art

[0002] The anchor of a suspension bridge is the anchorage end of the main cable, and its foundation is the key to the stress of the suspension bridge. Therefore, the stress, deformation and displacement of the anchor foundation must be strictly limited. The caisson foundation structure has become the main foundation structure type for the anchor of a suspension bridge due to its good stress performance, mature construction technology and low project cost.

[0003] With the continuous increase in the span of suspension bridges, the main cable stress increases, and the size of the anchor structure is getting larger and larger. For example, the caisson foundation of the north anchor of Wufengshan Yangtze River Bridge is 100.7m long, 72.1m wide, and 56m high, and the caisson foundation of the north anchor of the north channel bridge of Zhangjinggao Yangtze River Bridge is 75m long, 70m wide, and 57m high. The increase in the size of the anchor foundation will not only increase the project cost, but also increase the construction difficulty of the caisson foundation sharply. The anchor caisson foundation is mainly affected by the tension of the main cable, and its anti-slip and anti-overturning performance is the key to the structural design. In order to improve the anti-slip and anti-overturning performance of the caisson, optimize the caisson structure design, and reduce the project cost, the super-large caisson foundation can be split into two small caissons, one front caisson and one rear caisson. The front caisson has a small mass and the rear caisson has a large mass. The two are separated by a certain distance and connected by a tie beam to form a split caisson foundation.

[0004] At the same time, for cross-sea suspension bridges, under complex and harsh marine environmental conditions, it is more convenient and quicker to set the caisson foundation on the seabed. The submarine caisson foundation is a caisson structure prefabricated on land, which is then directly set in the deep-water foundation. For example, the caisson foundation of the 4# pier of the Xi'aomen highway-railway dual-use bridge adopts a submarine caisson foundation.

[0005] However, the construction of the split-type submarine caisson foundation for anchoring a suspension bridge mainly faces the following difficulties: (1) Since there is no need to excavate soil for sinking, the caisson load is borne only by the foundation at the bottom of the caisson, so the bearing capacity and flatness of the foundation are required to be high, and conventional foundation treatment methods cannot meet the requirements; (2) Since the tie beam exists between the two caissons, the subsequent tie beam construction requires that the caisson must be accurately positioned and sunk, especially the relative error of the positioning of the two caissons needs to be strictly controlled; (3) As the tie beam is a force-transmitting component, its quality requirements are high. However, the construction of underwater tie beams faces problems such as difficulty in stopping water, limited working surface for steel bar tying, and difficulty in concrete pouring, which makes the construction difficult. Summary of the invention

[0006] The present invention provides a method and device for constructing a split-type submarine caisson foundation for an anchored suspension bridge. Compared with a traditional submarine caisson foundation construction method, the caisson foundation of the present invention has high bearing capacity and flatness, can be applied to various geological conditions, and has good applicability; it can also achieve centimeter-level positioning and sinking of the caisson, which greatly improves the positioning accuracy of the caisson compared with the past; at the same time, it solves the construction problem of reinforced concrete tie beams with large spans and high head differences, and the overall construction period is short and the cost is low.

[0007] The above-mentioned split-type submarine caisson foundation includes a caisson, a tie beam, and a top plate. The caisson includes a front well and a rear well, the front well is lighter in weight, and the rear well is heavier in weight; the upper ends of the front well and the rear well are both connected to the top plate; one end of the tie beam is connected to the top plate of the front well, and the other end is connected to the top plate of the rear well.

[0008] The technical solution of the present invention is: a method for constructing a suspension bridge anchor split-type submarine caisson foundation, comprising the following steps:

[0009] Including: foundation pit excavation, concrete replacement, steel caisson manufacturing, undocking and floating, positioning and sinking, bottom sealing and core filling, sandwich wall concrete pouring, tie beam construction, cover plate construction and gravel backfilling;

[0010] The processes of foundation pit excavation, caisson manufacturing, undocking and floating, bottom sealing and core filling, sandwich wall concrete pouring, cover plate construction, and gravel backfilling are similar to conventional caisson construction methods and will not be described in detail here;

[0011] After the excavation of the foundation pit is completed, the concrete replacement includes pouring self-leveling, non-dispersing concrete of no more than 2m at the bottom of the foundation pit, and its construction steps include pouring point arrangement, foundation pouring device erection, and underwater concrete pouring; the positioning sinking includes using an automatic positioning anchor cable device, a caisson leveling and support device to achieve water injection and sinking of the caisson and rapid and high-precision positioning;

[0012] After the front well and the rear well sink and stabilize, the tie beam construction includes constructing a reinforced concrete structure between the front well and the rear well to connect them as a whole. The construction steps include hanging and lowering the tie beam casting device, floating casting of tie beam concrete, construction of the joint between the caisson and the tie beam casting device, dry pouring of the remaining tie beam concrete, and dismantling of the tie beam casting device.

[0013] According to a method for constructing a suspension bridge anchored split-type submarine caisson foundation provided by the present invention, the pouring points are arranged in such a way that the spacing between adjacent pouring points is determined according to the fluidity of self-leveling, non-dispersing concrete, so that the flow areas of all pouring points cover the entire pouring area.

[0014] According to a suspension bridge anchor split-type submarine caisson foundation construction method provided by the present invention, the method of setting up the foundation casting device includes setting up one end of the foundation casting device on a floating crane and placing the other end on a casting point.

[0015] According to a method for constructing a suspension bridge anchor split-type submarine caisson foundation provided by the present invention, the underwater concrete pouring method includes determining a pouring sequence of pouring points, and pouring all pouring points in sequence.

[0016] According to a method for constructing a suspension bridge anchored split-type submarine caisson foundation provided by the present invention, the method for hoisting a tie beam casting device includes using a floating crane to hoist the tie beam casting device above a designed position of the tie beam, and slowly lowering it to the water surface until the tie beam casting device floats by itself.

[0017] According to a method for constructing a split-type submarine caisson foundation for an anchored suspension bridge provided by the present invention, the method for floating casting of tie beam concrete comprises: when the tie beam casting device is in a floating state, concrete is cast into the tie beam casting device by using a concrete mixing ship, and at this time, the draft of the tie beam casting device gradually increases until the tie beam casting device sinks to the designed position of the tie beam.

[0018] According to a method for constructing a split-type submarine caisson foundation for an anchored suspension bridge provided by the present invention, the method for constructing the joint between the caisson and the tie beam casting device includes providing a water-stopping structure at the connection between the front caisson, the rear caisson and the tie beam, and then pumping out seawater at the connection to form a dry construction environment.

[0019] According to a suspension bridge anchor split-type submarine caisson foundation construction method provided by the present invention, the method of dry pouring the remaining tie beam concrete includes continuing to pour concrete into the tie beam pouring device until the tie beam casting is completed.

[0020] According to a suspension bridge anchor split-type submarine caisson foundation construction method provided by the present invention, the method for removing the tie beam casting device includes removing the entire tie beam casting device after the tie beam concrete is completely solidified.

[0021] A foundation pouring device, which is used in any of the above-mentioned methods for constructing a split-type submarine caisson foundation for an anchored suspension bridge, comprises: a guide frame, a concrete conduit, a roller and a support frame, wherein the guide frame is a truss structure, one end of which is fixedly connected to a floating crane, and the other end extends downward into the sea; one end of the concrete conduit is connected to a hopper on the floating crane, and the other end passes through the guide frame and extends downward into the sea to connect to the support frame; the support frame is placed on a pouring point; the bottom of the concrete conduit is 20 cm higher than the bottom of the support frame; and the roller is installed in the gap between the guide frame and the concrete conduit.

[0022] An automatic positioning anchor cable device, which is used in any of the above-mentioned methods for constructing a split-type submarine caisson foundation for an anchored suspension bridge, comprises: a gravity anchor, an anchor cable, a continuous jack, an automatic positioning controller and a monitor, wherein one end of the anchor cable is connected to the gravity anchor, and the other end is connected to the continuous jack; the gravity anchor is anchored on the seabed around the caisson foundation; the continuous jack is connected to the caisson; the automatic positioning controller is installed on the continuous jack and is used to control the continuous jack to retract and release the anchor cable; the monitor is connected to the automatic positioning controller through electrical signals and is used to monitor the plane position and inclination of the caisson and the tension of the anchor cable.

[0023] A caisson leveling and supporting device, which is used in any of the above-mentioned methods for constructing a split-type submarine caisson foundation for an anchored suspension bridge, and comprises: supporting piles, leveling jacks and capsule pads, wherein the lower ends of the supporting piles are supported on a concrete foundation, and the upper ends are connected to the leveling jacks; the leveling jacks can support the entire caisson to achieve precise control of the inclination of the caisson; the capsule pads are hollow structures with certain expansion properties, which are arranged at the bottom of the caisson, and when quick-hardening mortar is poured into the capsule pads, the capsule pads can rapidly expand and fill the gap between the caisson and the concrete foundation.

[0024] A tie beam casting device, which is used in any of the above-mentioned methods for constructing a split-type submarine caisson foundation for an anchored suspension bridge, comprising: a bottom plate, a web plate, a temporary partition plate and an inner support, wherein the bottom plate is perpendicular to both sides of a front well and a rear well and is respectively vertically connected to the web plate, and the bottom plate is parallel to both sides of the front well and the rear well and is respectively vertically connected to the temporary partition plate; the bottom plate, the web plate and the temporary partition plate together form a semi-enclosed structure; the inner support is arranged in the semi-enclosed structure in a "well" shape; the temporary partition plate can be removed at any time.

[0025] The advantages of the present invention are:

[0026] 1. The present invention provides a detailed split-type submarine caisson foundation construction method for the first time at home and abroad, solving the construction difficulties of the split-type caisson foundation.

[0027] 2. The present invention adopts a self-leveling, non-dispersing concrete replacement foundation treatment solution, which solves the problems of insufficient bearing capacity and poor flatness of the foundation after excavation. It can be applied to various geological conditions and has good applicability. At the same time, it provides a large-scale underwater concrete pouring construction method in open sea areas without cofferdam conditions, saving the construction cost of cofferdams and offshore construction platforms.

[0028] 3. The present invention adopts an automatic positioning anchor cable device, a caisson leveling and supporting device, which can achieve centimeter-level positioning and sinking of the caisson, greatly improving the positioning accuracy of the caisson compared with the past, and provides a prerequisite for the construction of the foundation tie beam of the split-type submarine caisson.

[0029] 4. The present invention proposes for the first time a construction scheme for floating cast tie beams, which solves the construction difficulties of reinforced concrete tie beams with large spans and high head differences. Compared with the conventional scheme of first constructing a cofferdam and then draining the water, the construction period is shorter and the cost is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic elevation diagram of the split-type submarine caisson foundation of the present invention;

[0031] Figure 2 It is a schematic plan view of the split-type submarine caisson foundation of the present invention;

[0032] Figure 3 It is a schematic diagram of a construction method of a suspension bridge anchor split-type submarine caisson foundation according to the present invention;

[0033] Figure 4 It is a plan view of the foundation pouring device of the present invention;

[0034] Figure 5 It is a schematic elevation diagram of the foundation pouring device of the present invention;

[0035] Figure 6 It is a schematic diagram of the underwater concrete pouring construction method of the present invention;

[0036] Figure 7 It is a schematic plan view of the automatic positioning anchor cable device of the present invention;

[0037] Figure 8 It is a schematic elevation view of the automatic positioning anchor cable device of the present invention;

[0038] Fig. 9 It is a schematic diagram of the caisson leveling and supporting device of the present invention;

[0039] Fig.10 It is a schematic plan view of the tie beam casting device of the present invention;

[0040] Fig.11 It is a schematic elevation view of the tie beam casting device of the present invention;

[0041] Fig.12 This is a schematic diagram of the hanging of the tie beam casting device of the present invention;

[0042] Fig.13 This is a schematic diagram of floating pouring of tie beam concrete according to the present invention;

[0043] Fig.14 It is a schematic diagram of the construction of the caisson and tie beam steel shell joint according to the present invention.

[0044] Among them: 2—foundation pouring device; 21—guide frame; 22—conduit; 23—roller; 24—support frame; 311—gravity anchor; 312—anchor cable; 313—continuous jack; 314—automatic positioning controller; 315—monitor; 321—support pile; 322—leveling jack; 323—capsule support pad; 324—reaction seat; 325—limiting hoop; 41—bottom plate; 42—web plate; 43—temporary partition; 44—internal support. DETAILED DESCRIPTION

[0045] The embodiments of the present invention are described in detail below, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0046] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0047] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0048] The present invention relates to a method and device for constructing a split-type submarine caisson foundation for an anchored suspension bridge. The caisson foundation has high bearing capacity and flatness, can be applied to various geological conditions, and has good applicability. The caisson can also be positioned and sunk at the centimeter level, which greatly improves the positioning accuracy of the caisson compared with the past. At the same time, the construction problem of reinforced concrete tie beams with large spans and high head differences is solved, and the overall construction period is short and the cost is low.

[0049] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0050] A method for constructing a suspension bridge anchor split-type submarine caisson foundation, specifically, Figure 3 As shown, including:

[0051] Foundation pit excavation, concrete replacement, steel caisson manufacturing, undocking and floating, positioning and sinking, bottom sealing and core filling, sandwich wall concrete pouring, tie beam construction, cover plate construction and gravel backfilling;

[0052] The processes of foundation pit excavation, caisson manufacturing, undocking and floating, bottom sealing and core filling, sandwich wall concrete pouring, cover plate construction, and gravel backfilling are similar to the conventional caisson construction method and will not be described in detail here.

[0053] After the excavation of the foundation pit is completed, the concrete replacement includes pouring self-leveling, non-dispersing concrete of no more than 2m at the bottom of the foundation pit, and its construction steps include pouring point arrangement, foundation pouring device erection, and underwater concrete pouring; the positioning sinking includes using an automatic positioning anchor cable device, a caisson leveling and support device to achieve water injection and sinking of the caisson and rapid and high-precision positioning;

[0054] After the front well and the rear well sink and stabilize, the tie beam construction includes constructing a reinforced concrete structure between the front well and the rear well to connect them as a whole. The construction steps include hanging and lowering the tie beam casting device, floating casting of tie beam concrete, construction of the joint between the caisson and the tie beam casting device, dry pouring of the remaining tie beam concrete, and dismantling of the tie beam casting device.

[0055] In some embodiments, Figure 6 As shown, the above-mentioned pouring point arrangement is optimized. The method of pouring point arrangement in this embodiment includes determining the spacing between adjacent pouring points according to the fluidity of self-leveling and non-dispersing concrete, so that the flow area of ​​all pouring points covers the entire pouring area.

[0056] like Figure 6 As shown, in this embodiment, the pouring points are arranged in a matrix manner, and each pouring point on the same row is numbered in sequence from left to right, and the distance between the pouring points is 6-10m.

[0057] In some embodiments, Figure 6 As shown, the above-mentioned underwater concrete pouring is optimized. The method for underwater concrete pouring in this embodiment includes determining the pouring sequence of pouring points, and pouring all pouring points in sequence.

[0058] Specifically, when pouring concrete at a pouring point, if the concrete of this pouring point is buried deeper than 0.3m into the concrete conduit at the next pouring point, the concrete pouring of this pouring point is stopped and the concrete pouring of the next pouring point is started;

[0059] In this embodiment, if Figure 6As shown, firstly, the 1# pouring point is poured by the plug-pulling method, and the pouring is stopped after the bottom of the concrete conduit at the 2# pouring point is buried at a depth of not less than 0.3m. Then the 2# pouring point is poured by the plug-pulling method, and so on. After all the pouring points in a single horizontal row are completed, the same method is used to pour the next row of horizontal pouring points until the concrete pouring of all the pouring points in the foundation pit is completed.

[0060] In some embodiments, Fig.12 As shown, the hoisting of the above-mentioned tie beam casting device is optimized. The method for hoisting the tie beam casting device in this embodiment includes using a floating crane to hoist the tie beam casting device above the designed position of the tie beam, and slowly lowering it to the water surface until the tie beam casting device floats by itself.

[0061] In some embodiments, Fig.13 As shown, the above-mentioned floating pouring of tie beam concrete is optimized. The method for floating pouring of tie beam concrete in this embodiment includes pouring concrete into the tie beam pouring device by using a concrete mixing ship when the tie beam pouring device is in a floating state. At this time, the draft of the tie beam pouring device gradually increases until the tie beam pouring device sinks to the designed position of the tie beam.

[0062] In fact, if Fig.13 As shown, in this embodiment, two supporting brackets are arranged below the design position of the tie beam, and the two supporting brackets are respectively connected to the walls of the front well and the rear well to support the tie beam casting device to prevent the tie beam casting device from further sinking when continuing to pour concrete into the tie beam casting device.

[0063] In some embodiments, Fig.14 As shown, the construction of the joint between the caisson and the tie beam casting device is optimized. The method for constructing the joint between the caisson and the tie beam casting device in this embodiment includes setting a water-stop structure at the connection between the front well, the rear well and the tie beam, and then pumping out the seawater at the connection to form a dry construction environment, which is convenient for the subsequent dry pouring of the tie beam concrete.

[0064] A foundation pouring device is used for replacing concrete in any of the above-mentioned methods for constructing a suspension bridge anchor split-type submarine caisson foundation, specifically, Figure 4 , 5 As shown, it includes: a guide frame 21, a concrete conduit 22, a roller 23 and a support frame 24. The guide frame 21 is a truss structure, one end of which is fixedly connected to the floating crane, and the other end extends downward into the sea; one end of the concrete conduit 22 is connected to the hopper on the floating crane, and the other end passes through the guide frame 21 and extends downward into the sea to connect with the support frame 24; the support frame 24 is placed on the pouring point; the bottom of the concrete conduit 22 is 20 cm higher than the bottom of the support frame 24; the roller 23 is installed in the gap between the guide frame 21 and the concrete conduit 22.

[0065] During actual construction, a number of guide frames 21 are first arranged at intervals of 6-10m on the side of the floating crane. In this embodiment, there are four guide frames 21, which are truss structures and are welded and fixed to the floating crane. A concrete conduit 22 is installed on the guide frame 21. A number of rollers 23 are installed in the gap between the guide frame 21 and the concrete conduit 22. The interval between each roller 23 is 2m. The rollers 23 limit the plane displacement of the concrete conduit 22 while allowing the concrete conduit 22 to move freely in the vertical direction, thereby adapting to the change of tidal range. A support frame 24 is used to fix the bottom of the concrete conduit 22 on the casting point arranged on the seabed. The bottom of the concrete conduit 22 is 20cm higher than the bottom of the support frame to avoid clogging the concrete conduit 22 during concrete casting.

[0066] An automatic positioning anchor cable device is used for positioning and sinking in any of the above-mentioned methods for constructing a suspension bridge anchor split-type submarine caisson foundation. Specifically, Figure 7 , 8 As shown, it includes: a gravity anchor 311, an anchor cable 312, a continuous jack 313, an automatic positioning controller 314 and a monitor 315, wherein one end of the anchor cable 312 is connected to the gravity anchor 311, and the other end is connected to the continuous jack 313; the gravity anchor 311 is anchored on the seabed around the caisson foundation; the continuous jack 313 is connected to the caisson; the automatic positioning controller 314 is installed on the continuous jack 313, and is used to control the continuous jack 313 to retract and release the anchor cable 312; the monitor 315 is connected to the automatic positioning controller 314 through electrical signals, and is used to monitor the plane position and inclination of the caisson, and the tension of the anchor cable 312.

[0067] In this case, 8 gravity anchors 311, 8 anchor cables 312, 8 continuous jacks 313, 8 automatic positioning controllers 314, and 1 monitor 315 are used to form an automatic positioning anchor cable device. Under complex marine environmental conditions, the anchor cable 312 is a flexible connecting rope, which can greatly reduce the wave force on the automatic positioning anchor cable device and reduce the construction cost.

[0068] The monitor 315 can monitor the plane position, inclination, tension of the anchor cable 312 and water injection volume of the caisson compartment in real time. The automatic positioning controller 314 can control the continuous jack 313 to retract and release the anchor cable 312 through the PLC (programmable logic controller), thereby realizing automatic high-precision positioning of the plane position of the caisson.

[0069] A caisson leveling and supporting device is used for positioning and sinking in any of the above-mentioned methods for constructing a suspension bridge anchor split-type submarine caisson foundation. Specifically, Fig. 9As shown, it includes: a support pile 321, a leveling jack 322 and a capsule support pad 323. The lower end of the support pile 321 is supported on the concrete foundation, and the upper end is connected to the leveling jack 322; the leveling jack 322 can support the entire caisson to achieve precise control of the inclination of the caisson; the capsule support pad 323 is a cavity structure with a certain expansion performance, which is arranged at the bottom of the caisson. When pouring fast-hardening mortar into the capsule support pad 323, the capsule support pad 323 can expand rapidly and fill the gap between the caisson and the concrete foundation.

[0070] In this embodiment, Fig. 9 As shown, the caisson leveling and supporting device also includes a reaction seat 324 and a limiting hoop 325. One end of the reaction seat 324 is installed on the top of the leveling jack 322, and the other end is connected to the caisson; the limiting hoop 325 connects the supporting pile 321 and the reaction seat 324;

[0071] When pouring quick-hardening mortar into the capsule support pad 323, the grouting pipe and the exhaust pipe both penetrate the caisson and extend into the capsule support pad 323. The grouting pipe is used to pour quick-hardening mortar into the capsule support pad 323, and the exhaust pipe is used to exhaust the air of the capsule support pad 323. After the quick-hardening mortar 334 solidifies, the supporting piles 331, the leveling jack 332, the reaction seat 324 and the limiting hoop 325 can be removed. At this time, the weight of the caisson can be converted from the supporting piles 331 and the leveling jack 332 to the capsule support pad 333. Subsequently, water is injected into the caisson for ballast to ensure the stability of the caisson.

[0072] A tie beam casting device is used for the tie beam construction in any of the above-mentioned methods for constructing a suspension bridge anchor split-type submarine caisson foundation, specifically, Fig.10 , 11 As shown, it includes: a bottom plate 41, a web 42, a temporary partition 43 and an inner support 44. The bottom plate 41 is perpendicular to the two sides of the front well and the rear well and is vertically connected to the web 42 respectively. The bottom plate 41 is parallel to the two sides of the front well and the rear well and is vertically connected to the temporary partition 43 respectively; the bottom plate 41, the web 42 and the temporary partition 43 together form a semi-enclosed structure; the inner support 44 is arranged in the semi-enclosed structure in a "well" shape; the temporary partition 43 can be removed at any time.

[0073] When performing the dry pouring step of the remaining tie beam concrete, after the seawater at the connection part is pumped out, the temporary partition 43 is first removed, and then the remaining concrete is poured into the tie beam pouring device until the tie beam concrete is completely poured.

[0074] During the dismantling step of the tie beam casting device, after the tie beam concrete is completely solidified, the remaining bottom plate 41 and web plate 42 of the tie beam casting device are removed one by one.

[0075] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for constructing a suspension bridge anchor split-type submarine caisson foundation, characterized in that: include: Excavation of foundation pit, concrete replacement, steel caisson manufacturing, undocking and floating, positioning and sinking, bottom sealing and core filling, sandwich wall concrete pouring, tie beam construction, cover plate construction and gravel backfilling; After the excavation of the foundation pit is completed, the concrete replacement includes pouring self-leveling, non-dispersing concrete of no more than 2m at the bottom of the foundation pit, and its construction steps include pouring point arrangement, foundation pouring device erection, and underwater concrete pouring; the positioning sinking includes using an automatic positioning anchor cable device, a caisson leveling and support device to achieve water injection and sinking of the caisson and rapid and high-precision positioning; After the front well and the rear well sink and stabilize, the tie beam construction includes constructing a reinforced concrete structure between the front well and the rear well to connect them as a whole. The construction steps include hanging and lowering the tie beam casting device, floating casting of tie beam concrete, construction of the joint between the caisson and the tie beam casting device, dry pouring of the remaining tie beam concrete, and dismantling of the tie beam casting device.

2. A suspension bridge anchor split-type submarine caisson foundation construction method as claimed in claim 1, characterized in that: The method for arranging the pouring points includes determining the spacing between adjacent pouring points according to the fluidity of the self-leveling, non-dispersing concrete, so that the flow areas of all pouring points cover the entire pouring area.

3. A suspension bridge anchor split-type submarine caisson foundation construction method as claimed in claim 1, characterized in that: The method for underwater concrete pouring includes determining the pouring sequence of pouring points, and pouring all the pouring points in sequence.

4. A suspension bridge anchor split-type submarine caisson foundation construction method as claimed in claim 1, characterized in that: The hanging and placing of the tie beam casting device includes using a floating crane to hang the tie beam casting device above the designed position of the tie beam, and slowly lowering it to the water surface until the tie beam casting device floats by itself.

5. The method for constructing a suspension bridge anchor split-type submarine caisson foundation as claimed in claim 1, characterized in that: The floating pouring of tie beam concrete includes pouring concrete into the tie beam pouring device by using a concrete mixing ship when the tie beam pouring device is in a floating state, and the draft of the tie beam pouring device gradually increases until the tie beam pouring device sinks to the designed position of the tie beam.

6. A suspension bridge anchor split-type submarine caisson foundation construction method as claimed in claim 1, characterized in that: The construction of the joint between the caisson and the tie beam casting device includes setting a water-stop structure at the connection between the front caisson, the rear caisson and the tie beam, and then pumping out the seawater at the connection to form a dry construction environment.

7. A foundation pouring device, characterized in that: The foundation pouring device is used for a suspension bridge anchor split-type submarine caisson foundation construction method as described in any one of claims 1 to 6, comprising: a guide frame (21), a concrete conduit (22), a roller (23) and a support frame (24), wherein the guide frame (21) is a truss structure, one end of which is fixedly connected to a floating crane, and the other end of which extends downward into the sea; one end of the concrete conduit (22) is connected to a hopper on the floating crane, and the other end of the concrete conduit (22) passes through the guide frame (21) and extends downward into the sea to connect with the support frame (24); the support frame (24) is placed at a pouring point; the bottom of the concrete conduit (22) is 20 cm higher than the bottom of the support frame (24); and the roller (23) is installed in the gap between the guide frame (21) and the concrete conduit (22).

8. An automatic positioning anchor cable device, characterized in that: The automatic positioning anchor cable device is used in a suspension bridge anchor split-type submarine caisson foundation construction method as described in any one of claims 1 to 7, comprising: a gravity anchor (311), an anchor cable (312), a continuous jack (313), an automatic positioning controller (314) and a monitor (315), wherein one end of the anchor cable (312) is connected to the gravity anchor (311), and the other end is connected to the continuous jack (313); the gravity anchor (311) is anchored on the seabed around the caisson foundation; the continuous jack (313) is connected to the caisson; the automatic positioning controller (314) is installed on the continuous jack (313) and is used to control the continuous jack (313) to retract and release the anchor cable (312); the monitor (315) is connected to the automatic positioning controller (314) through electrical signals and is used to monitor the plane position and inclination of the caisson and the tension of the anchor cable (312).

9. A caisson leveling and supporting device, characterized in that: The caisson leveling and supporting device is used in a suspension bridge anchor split-type submarine caisson foundation construction method as described in any one of claims 1 to 8, comprising: support piles (321), leveling jacks (322) and capsule pads (323), wherein the lower end of the support piles (321) is supported on a concrete foundation, and the upper end is connected to the leveling jacks (322); the leveling jacks (322) can support the entire caisson to achieve precise control of the inclination of the caisson; the capsule pads (323) are hollow structures with certain expansion properties, arranged at the bottom of the caisson, and when quick-hardening mortar is poured into the capsule pads (323), the capsule pads (323) can rapidly expand and fill the gap between the caisson and the concrete foundation.

10. A tie beam casting device, characterized in that: The tie beam casting device is used for a suspension bridge anchor split-type submarine caisson foundation construction method as described in any one of claims 1 to 9, comprising: a bottom plate (41), a web plate (42), a temporary partition plate (43) and an inner support (44), wherein the bottom plate (41) is perpendicular to the two sides of the front well and the rear well and is respectively vertically connected to the web plate (42), and the bottom plate (41) is parallel to the two sides of the front well and the rear well and is respectively vertically connected to the temporary partition plate (43); the bottom plate (41), the web plate (42) and the temporary partition plate (43) together form a semi-enclosed structure; the inner support (44) is arranged in the semi-enclosed structure in a "well" shape; the temporary partition plate (43) can be removed at any time.

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