An operating method for caisson pressure sinking process

Abstract

The present invention relates to an operating method for a caisson pressure sinking process, which uses an assembled corbel to configure a through-hole oil cylinder and a sinking-assisting device. First, a lifting through-hole oil cylinder is used to replace the commonly used tensioning and anchoring through-hole oil cylinder. The lifting through-hole oil cylinder is used to configure a steel strand and anchor plate combination to prevent uneven force on each strand during operation. The anchor plate for clamping the steel strand is placed on top of the lifting through-hole oil cylinder, facilitating replacement or repositioning of the anchor plate clip in the event of accidental damage, jamming, or detachment. The present invention can improve and resolve the drawbacks of the current caisson pressure-assisted sinking process that uses a through-hole oil cylinder and steel strand, anchor plate, and fixed anchor combination.

Description

Technical Field

[0001] The present invention relates to the field of underground engineering caisson construction, in particular to an operating method of a caisson pressure sinking process. Background Art

[0002] In recent years, the advantages of caisson pressure-assisted sinking technology have become more prominent and have been gradually promoted and applied. However, it is different from working conditions such as lifting with through-hole cylinders, VSM shaft operations, and steel strand tensioning. Figure 1 Figure 2 is a commonly used schematic diagram of a caisson sinking process using pressure (force). When a caisson through-hole oil cylinder, steel strands, anchor plates, and fixed anchors are used as the loading source, improper operation can cause the anchor plate clips to become stuck, the steel strands to become loose, and a group of steel strands within the through-hole oil cylinder to break due to uneven force, affecting the efficiency and safety of caisson construction. Although a through-hole oil cylinder with a tie rod and bolt pair can replace the steel strand and anchor plate combination to avoid the above problems, this combination is much more complicated to operate than the steel strand and anchor plate combination and is rarely used in actual construction. Summary of the Invention

[0003] In response to the above improper operations and safety hazards, the present invention proposes an operating method for the caisson pressure sinking process according to different situations to improve and solve the disadvantages of the current caisson pressure-assisted sinking process which uses a combination of through-core oil cylinders and steel strands, anchor plates and fixed anchors.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The invention discloses an operating method for a caisson pressure sinking process, which adopts an assembled bull leg to match a through-hole cylinder and a sinking aid. First, a through-hole cylinder for lifting is adopted to replace a commonly used through-hole cylinder for tensioning and anchoring. The through-hole cylinder for lifting is adopted to configure a steel strand and an anchor plate combination to prevent uneven force on each strand during operation. The anchor plate for clamping the steel strand is placed on the top of the through-hole cylinder for lifting, so as to facilitate replacement or return of the anchor plate clip when it is accidentally damaged, stuck, or popped off.

[0006] Furthermore, when using a through-hole cylinder to configure a steel strand and anchor plate combination to implement the caisson sinking process, when the through-hole cylinder for lifting reaches the set maximum loading value, the ballast force of the cylinder is balanced with the resistance of the soil plug at the bottom of the well, the support force of the foundation and the buoyancy during the water sinking condition, and the caisson no longer moves downward, the sinking process is completed.

[0007] Furthermore, when the caisson is being pressed down, the oil supply pressure of the pump station is set so that the through-hole oil cylinder for lifting has two working conditions: maximum loading value and pressure maintaining value. When the caisson is being pressed down, when the through-hole oil cylinder for lifting reaches the set maximum loading value, the ballast force and the lifting force of the caisson are balanced, and the caisson is no longer moving down, the tool anchor plate 2 of the through-hole oil cylinder for lifting is put into working state, the steel strand is clamped, the tool anchor plate 1 of the through-hole oil cylinder for lifting releases the steel strand, the through-hole oil cylinder for lifting is retracted to the bottom, and then the working anchor plate is re-clamped to the steel strand, the upper tool anchor plate 2 is opened, and at the same time, the pump station enters the pressure maintaining value working condition, and the through-hole oil cylinder for lifting is always kept in the jacking mode, so that the steel strand is in In the low-tension state, the caisson completes the sinking process and switches from pressure sinking to the bottom mud excavation mode. The continuous increase in the amount of soil excavated causes the ballast force and the lifting force of the caisson to be unbalanced. The caisson slowly moves downward and the tension of the steel strands decreases. At this time, the pump station starts automatically, and the lifting cylinder is lifted to restore the low-tension state of the steel strands. The pump is stopped to ensure that the net distance between the tool anchor plate of the lifting cylinder on the caisson's bracket and the fixed anchor at the top of the pull-out pile remains unchanged. The steel strands are in a tensioned working condition from beginning to end to avoid some steel strands from loosening and losing load, and the load on the remaining steel strands becomes larger and larger, resulting in a group of steel strands in the lifting cylinder being unevenly stressed and the serious consequences brought about.

[0008] Furthermore, when the pump station maintains a low-pressure oil supply state, the lifting through-core cylinder maintains a certain jacking force, always keeping the steel strands tensioned, the caisson sinks slightly, and the lifting through-core cylinder is lifted. Each steel strand can always be in a small-load tensioned state without loosening, thereby avoiding a group of steel strands in the lifting through-core cylinder from being loose due to uneven force, and some steel strands being overloaded and breaking wires or strands, and a strand of overloaded steel strand clips in the anchor plate being stuck because they cannot be detached from the steel strand due to overload.

[0009] Furthermore, during the caisson loading and sinking process, when the loading force of the lifting through-core cylinder reaches the upper limit of the set value and the sinking stops, the hydraulic pump station is operated to briefly switch the lifting through-core cylinder from the extension working condition to the retraction mode, and then the tool anchor plate 2 of the through-core cylinder and the tool anchor plate 1 are released to exchange the clamping steel strand mode. With the slight retraction of the lifting through-core cylinder, the tension of the taut steel strand decreases and the elastic variable value increases, thereby eliminating the adverse consequences of the soil compression rebound force on the steel strand and the problem of the tool anchor plate clip jumping out of the cone groove.

[0010] Furthermore, the taper angle between the tool anchor plate and the anchor plate clip is reduced to reduce the chance of getting stuck.

[0011] The beneficial effects of the present invention are:

[0012] The advantage of using a through-hole cylinder for lifting to replace the commonly used through-hole cylinder for tensioning and anchoring is that the anchor plate for clamping the steel rope is placed on the top of the cylinder, which is convenient for replacing or returning the anchor plate clip when it is accidentally damaged, stuck, or popped off; in addition, the taper angle between the tool anchor plate and the clip is reduced to reduce the chance of getting stuck.

[0013] The invention can improve and solve the drawbacks of the current caisson pressure-assisted sinking process which adopts the combined operation of a through oil cylinder and a steel strand, an anchor plate and a fixed anchor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a common vertical view of the fixed bracket configuration through-hole oil cylinder caisson pressure (force) sinking process;

[0015] Figure 2 yes Figure 1 A partial enlarged view of the commonly used fixed bracket configuration through-core cylinder;

[0016] Figure 3 This is an elevational view of the sinking process of the caisson assembled type bracket fixed through-core oil cylinder and other sinking aids of the present invention;

[0017] Figure 4 This is a detailed diagram of a through-hole cylinder used for lifting and hoisting. DETAILED DESCRIPTION

[0018] The following is a further detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. The following figures are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0019] like Figure 3 As shown in Figure 4, the present invention employs an assembled corbel with a through-hole cylinder and a sinking aid to implement a caisson sinking process. The assembled corbel, through-hole cylinder, and sinking aid include an assembled main corbel 1, a through-hole cylinder for a horizontal tie rod 3, an auxiliary corbel 4 for a horizontal tie rod and its embedded parts 5, a through-hole cylinder for lifting 2, a steel strand 7, a pull-out pile 9, and an anchor 8 for securing a steel strand. The through-hole cylinder 2 includes a tool anchor plate 11, a tool anchor plate 2 12, an adjusting nut 13, an adjusting spring 14, and an anchor plate clip 15.

[0020] First, a lifting through-hole cylinder is used to replace the commonly used tensioning and anchoring through-hole cylinder, and the anchor plate that clamps the steel rope is placed on the top of the lifting through-hole cylinder to facilitate the replacement or return of the anchor plate clip 15 when it is accidentally damaged, stuck, or popped off; in addition, the cone angle between the tool anchor plate and the anchor plate clip 15 is reduced to reduce the chance of getting stuck.

[0021] When the caisson sinking process is implemented by using a through-core lifting cylinder 2 configured with a steel strand and an anchor plate, when the through-core lifting cylinder 2 reaches the set maximum loading value, and the ballast force of the cylinder is balanced with the resistance of the soil plug at the bottom of the well, the support force of the foundation and the buoyancy during the water sinking condition, and the caisson 10 no longer moves downward, the sinking process is completed.

[0022] like Figure 1 , as shown in 2, the conventional operation is to use the tension anchor cylinder as the pressure sinking booster cylinder; and the hoisting lifting cylinder as the pressure sinking booster cylinder:

[0023] The lifting cylinder's tool anchor plate 1 (tensioning cylinder) or tool anchor plate 2 (lifting cylinder) enters operation, clamping the steel strand. The lifting cylinder's working anchor plate releases the anchor plate, and the lifting cylinder unloads. However, at this point, the caisson is in a state of dynamic equilibrium under load. The caisson transitions from pressure sinking to bottom dredging and soil extraction. As the amount of soil extracted increases, the load balance is disrupted, and the caisson begins to move downward slightly. The clearance between the caisson's upper cylinder anchor plate clamping the steel strand and the fixed anchor at the top of the pullout pile shortens, causing the steel strand, which is elastically deformed and elongated, to relax somewhat, but the degree of relaxation varies between strands. When the caisson transitions from soil extraction to pressure sinking, some strands are subjected to greater stress than others. With the constant transition between operating conditions, some strands completely relax and lose their load, while the remaining strands experience increasing load. As a result, a group of steel strands in the through-hole cylinder may become loose due to uneven force, some steel strands may be overloaded and break wires or strands, and a strand of overloaded steel strand clip in the anchor plate may be stuck because it cannot be detached from the steel strand due to overload.

[0024] The solution adopted by the present invention is: the pump station maintains a low-pressure oil supply state, the oil cylinder maintains a certain jacking force, always keeps the steel strands tensioned, the caisson sinks slightly, and the oil cylinder rises, so that each steel strand can always be in a light-load tensioned state without loosening.

[0025] The use of a through-hole hydraulic cylinder for lifting is used to assemble a steel strand and anchor plate to prevent uneven force on each strand during operation. By setting the oil supply pressure of the pump station, the through-hole hydraulic cylinder has two working conditions: maximum loading value and pressure holding value. During the caisson's pressure sinking operation, when the cylinder reaches its maximum set load, the caisson's ballast force and lifting force reach equilibrium, and the caisson stops moving downward. The lifting through-hole cylinder 2's tool anchor plate 2 (12) enters its operating state, clamping the strand 7. The cylinder's tool anchor plate 1 (11) releases the strand 7, and the cylinder retracts to the bottom. The working anchor plate then re-clamps the strand 7, and the upper tool anchor plate 2 (12) is opened. Simultaneously, the pump station enters its pressure-holding mode, maintaining the cylinder in its lifting mode, keeping the strand 7 in a low tension state. The caisson completes its sinking process and transitions from pressure sinking to bottom dredging mode (7). The increasing amount of soil removed causes an imbalance between the caisson's ballast force and lifting force, causing the caisson to slowly move downward and the tension in the strand 7 to decrease. At this point, the pump station automatically activates, the cylinders lift, restoring the low tension in the strand 7, and the pump stops. This ensures that the net distance between the hydraulic cylinder tool anchor plate on the caisson bracket and the fixed anchor at the top of the pullout pile 9 remains constant, and the steel strands 7 remain in tension. This prevents some steel strands from slackening and losing their load, while the load on the remaining steel strands increases. This can prevent a group of steel strands in the through-cylinder from being unevenly stressed, with the resulting serious consequences.

[0026] In another case, during the caisson loading and sinking process, when the cylinder loading force reaches the set upper limit, the sinking process ends. Normally, the cylinder is unloaded. At this moment, the compressed soil rebounds forcefully like a compressed spring, causing the caisson to rise slightly, exerting upward tension on the steel strands and potentially causing the working anchor plate clips to jump out of the conical grooves.

[0027] The operating method of the present invention for preventing the clip from falling out of the groove is as follows: after the sinking process is completed, the through-core oil cylinder is switched from the piston rod extending downward pressing working condition to the retraction working condition, the tension of the taut steel rope is reduced, the elastic variable value is increased, and the compression and rebound amount of the soil is offset, thereby eliminating the disadvantage that the working anchor plate clip jumps out of the conical groove due to the rebound force of the soil.

[0028] During the caisson loading and sinking process, when the cylinder loading force reaches the set upper limit and the sinking stops, operate the hydraulic pump station to briefly switch the through-hole cylinder from the extension mode to the retraction mode, and then enter the through-hole cylinder's tool anchor plate 2 and tool anchor plate 1 to release the anchor plates and exchange the clamping steel strand mode. As the cylinder retracts slightly, the tension of the taut steel strand decreases and the elastic variable value increases, eliminating the adverse consequences of the soil compression rebound force on the steel strand and the problem of the tool anchor plate clip jumping out of the cone groove.

Claims

1. A method for operating a caisson sinking process, using an assembled bracket, a through-hole cylinder and a sinking aid, characterized by: First, a lifting through-core oil cylinder is used to replace the commonly used tensioning and anchoring through-core oil cylinder. The lifting through-core oil cylinder is configured with a steel strand and an anchor plate combination to prevent uneven force on each steel strand during operation; the anchor plate for clamping the steel strand is placed on the top of the lifting through-core oil cylinder, which is convenient for replacing or returning the anchor plate clip when it is accidentally damaged, stuck, or popped off; when implementing the caisson pressure sinking process, the oil supply pressure of the pump station is set to make the lifting through-core oil cylinder have two working conditions of maximum loading value and pressure holding value; when the caisson is sinking, when the lifting through-core oil cylinder reaches the set maximum loading value, the ballast force and the lifting force of the caisson are balanced, and the caisson no longer moves downward, the tool anchor plate 2 of the lifting through-core oil cylinder is put into working state to clamp the steel strand, the tool anchor plate 1 of the lifting through-core oil cylinder releases the steel strand, the lifting through-core oil cylinder is retracted to the bottom, and then the working When the jacking action is resumed, the hydraulic cylinder is lifted and the tension of the steel strands is reduced, so that the hydraulic cylinder is lifted and the hydraulic cylinder is lowered to the working state of the jacking action.

2. The operating method of the caisson sinking process according to claim 1, characterized in that: When using a through-hole cylinder with a combination of steel strands and anchor plates to implement the caisson sinking process, the sinking process ends when the lifting through-hole cylinder reaches the set maximum loading value, and the ballast force of the cylinder is balanced with the resistance of the soil plug at the bottom of the well, the support force of the foundation and the buoyancy during the water sinking condition, and the caisson no longer moves downward.

3. The operating method of the caisson pressure sinking process according to claim 1, characterized in that: When the pump station maintains a low-pressure oil supply state, the lifting through-core cylinder maintains a certain jacking force, always keeping the steel strands tensioned, the caisson sinks slightly, and the lifting through-core cylinder is lifted. Each steel strand can always be in a tensioned state with a small load without being loose, thereby avoiding a group of steel strands in the lifting through-core cylinder from being unevenly stressed, some steel strands being loose, and some steel strands being overloaded and breaking wires or strands, and a certain overloaded steel strand clip in the anchor plate being unable to disengage from the steel strand due to overload and being stuck.

4. The operating method of the caisson pressure sinking process according to claim 1, characterized in that: During the caisson loading and sinking process, when the loading force of the lifting through-core cylinder reaches the upper limit of the set value and the sinking stops, operate the hydraulic pump station to briefly switch the lifting through-core cylinder from the top extension condition to the retraction mode, and then enter the lifting through-core cylinder tool anchor plate 2 and tool anchor plate 1 to release the anchor plate and exchange the clamping steel strand mode. With the slight retraction of the lifting through-core cylinder, the tension of the taut steel strand decreases and the elastic variable value increases, eliminating the adverse consequences of the soil compression rebound force on the steel strand and the problem of the tool anchor plate clip jumping out of the cone groove.

5. The operating method of the caisson pressure sinking process according to claim 1, characterized in that: The taper angle of the tool anchor plate and the anchor plate clip is reduced to reduce the chance of getting stuck.

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