An ultra-deep assembled vertical shaft underwater bottom sealing tool and a construction method thereof

Abstract

The application provides an ultra-deep assembled vertical shaft underwater bottom sealing tool and a construction method, and relates to the technical field of concrete bottom sealing construction. The tool abuts against the inner side wall or the reinforced ring beam when moving downward in the water-filled vertical shaft during the construction process. The multi-point abutment of the support assembly and the inner wall of the vertical shaft can provide reliable guidance and constraint for the tool, effectively inhibiting the position deviation caused by the disturbed water flow. The hydraulic hinge makes the support rod automatically retract when touching the obstacles such as the reinforced ring beam, and automatically open after passing through, realizing automatic obstacle avoidance without power. At the same time, cooperating with the speed control model constructed based on the size parameters of the vertical shaft and the tool parameters, the tool downward speed can be accurately controlled. Therefore, the application improves the downward stability and positioning accuracy of the tool in the deep water high pressure environment, and ensures that the tool is accurately pre-buried in the concrete bottom sealing without personnel diving.

Description

Technical Field

[0001] This invention generally relates to the field of concrete bottom sealing construction technology, and specifically to an underwater bottom sealing tooling and construction method for ultra-deep prefabricated vertical shafts. Background Technology

[0002] The VSM (Video Shaft Scraper) method, with its advantages of no dewatering, high degree of mechanization, and minimal impact on the surrounding environment, is gradually being promoted and applied in shaft engineering in water-rich and soft strata. Underwater concrete sealing is the core and critical control process in shaft construction, directly determining the structure's buoyancy resistance, seepage resistance, and load-bearing safety.

[0003] Generally, the engineering site is mainly composed of fluid-plastic to soft-plastic silty soil and silty clay, which have typical soft strata characteristics of high water content, high compressibility, high sensitivity and strong thixotropy. At the same time, the site is directly connected to the Yangtze River, with high water head, high pressure and close hydraulic connection. The total amount of bottom sealing concrete is nearly 6000 m³, the working water depth exceeds 57 m, and the hydrostatic pressure at the base reaches 6 bar. The deep soft soil strata adjacent to the river, the multi-layered ring beams, connecting beams, cutting edge, and inner lining are all superimposed on each other.

[0004] In deep-water, high-pressure environments, concrete is prone to segregation and dispersion. Large-section pouring is susceptible to problems such as cold joints, slag inclusions, and foundation disturbance, leading to an exponential increase in the difficulty of quality control. Underwater geogrids (tooling) are key filter components for sealing the bottom of soft strata, but existing laying tools and processes are only suitable for shallow water environments or flat foundations without internal obstacles. When sealing the bottom of ultra-deep, large-diameter vertical shafts with internal ring beams, connecting beams, cutting edges, and linings, the tooling is prone to positional instability and displacement due to disturbed water flow in deep-water, high-pressure environments, resulting in uneven strength distribution of the sealing concrete structure. Summary of the Invention

[0005] In view of the above-mentioned defects or deficiencies in the existing technology, it is desirable to provide an ultra-deep prefabricated vertical shaft underwater sealing fixture and construction method, which can suppress the positional displacement of the fixture due to the disturbance of water flow in the well during the sinking process in the water injection vertical shaft, improve the stability of the fixture's downward movement, and ensure uniform strength distribution of the concrete sealing structure.

[0006] In a first aspect, the present invention provides an ultra-deep prefabricated vertical shaft underwater sealing fixture, the fixture comprising a bracket and a support assembly hinged to the bracket; the support assembly is provided in at least three sets. The support assembly includes a first support rod and a second support rod whose ends are hinged to each other; the end of the first support rod away from the second support rod is hinged to the bracket; the hinge axes of the first support rod and the second support rod are both parallel to the horizontal direction. Hydraulic hinges are installed between the first support rod and the bracket, and between the second support rod and the first support rod, to limit the first maximum tilt angle between the first support rod and the bracket, and the second maximum tilt angle between the second support rod and the first support rod; The support assembly has target size parameters and target shape parameters. When the tooling moves downward at the maximum downward speed in a water-filled shaft, the first support rod and the second support rod are used to slide against the inner wall of the shaft or the reinforcing ring beam inside the shaft.

[0007] Secondly, the present invention provides a construction method for an ultra-deep prefabricated vertical shaft underwater bottom sealing fixture, applied to the fixture described in the first aspect, comprising: S1: Obtain the vertical shaft dimensions; the vertical shaft dimensions include: the inner diameter of the vertical shaft, the width of the reinforcing ring beam, and the height difference between the reinforcing ring beam and the bottom of the vertical shaft. S2: Determine the tooling size parameter constraints based on the shaft size parameters; S3: Construct a first function relating the tooling's downward movement speed to the tooling's dimensional parameters and shape parameters; the tooling's dimensional parameters include: the length of the first support rod and the length of the second support rod; the tooling's shape parameters include: the number of support components and the width of the support components along the horizontal direction; S4: Calculate the maximum downward movement speed, target size parameters, and target shape parameters of the tooling using the first function and the tooling size parameter constraints; S5: Prepare the tooling as described in the first aspect according to the target size parameters and target shape parameters; S6: The tooling is placed in a water-filled vertical shaft, and the tooling is controlled to move downward in the vertical shaft according to the maximum downward movement speed; S7: Construct a concrete seal for the bottom of the shaft and embed the tooling in the concrete seal.

[0008] According to the technical solution provided by the present invention, S2: determining the tooling size parameter constraints based on the vertical shaft size parameters includes: S2-1: Obtain the first constraint condition that the tooling dimensional parameters satisfy when the tooling passes through the reinforcing ring beam inside the shaft and abuts against the inner wall of the shaft or the reinforcing ring beam inside the shaft; the first constraint condition includes: the tooling can pass through the reinforcing ring beam, multiple support components can simultaneously abut against the inner wall of the shaft, and both the first support rod and the second support rod can fit against the surface of the bottom stratum. S2-2: Obtain the first conversion relationship between the support diameter, the shaft inner diameter and the width of the reinforcing ring beam that satisfy the first constraint condition, and the first maximum tilt angle of the first support rod relative to the support; S2-3: Substitute the first conversion relationship and the first maximum tilt angle into the first constraint condition to calculate the tooling size parameter constraint condition.

[0009] According to the technical solution provided by the present invention, the tooling dimensional parameter constraint condition is expressed as follows:

[0010] Where D0 is the inner diameter of the shaft. b To increase the width of the ring beam, H To enhance the height difference between the ring beam and the bottom of the shaft, L1 is the length of the first support rod, L2 is the length of the second support rod, and c is the first maximum tilt angle of the first support rod relative to the support frame.

[0011] According to the technical solution provided by the present invention, S3: Constructing a first function between the tooling downward movement speed and the tooling size parameters and tooling shape parameters, including: S3-1: Based on the support diameter, the shaft inner diameter and the first conversion relationship, calculate the volume of the support and the projected area of ​​the support along the horizontal plane. S3-2: Construct the force relationship equations for the tooling during its descent in water; S3-3: Substitute the volume of the support, the projected area of ​​the support along the horizontal plane, the tooling size parameters, and the tooling shape parameters into the force relationship to construct the first function.

[0012] According to the technical solution provided by the present invention, the first function is expressed as:

[0013] in, v Let ρ be the downward velocity of the tooling, ρ0 be the density of the tooling, ρ be the density of water, g be the acceleration due to gravity, V0 be the volume of the support, A0 be the projected area of ​​the support along the horizontal plane, and C be the velocity of the tooling. d Let n be the resistance coefficient of the tooling in water, n be the number of support components, and D be the diameter of the support.

[0014] According to the technical solution provided by the present invention, S4: Calculating the maximum downward movement speed, target size parameters, and target shape parameters of the tooling using the first function and the tooling size parameter constraints includes: S4-1: Set the target optimization function according to the first function; set the second constraint condition according to the tooling size parameter constraint condition; S4-2: Based on the target optimization function and the second constraint, with the tooling size parameters and tooling shape parameters as the search targets, the optimization algorithm is used to search for the target size parameters and target shape parameters that maximize the tooling's downward movement speed and minimize the cost. S4-3: The downward movement speed corresponding to the target size parameter and the target shape parameter is taken as the maximum downward movement speed.

[0015] According to the technical solution provided by the present invention, S4-2: Based on the objective optimization function and the second constraint condition, taking the tooling size parameters and tooling shape parameters as search targets, an optimization algorithm is used to search for the target size parameters and target shape parameters that maximize the tooling's downward movement speed and minimize the cost, including: S4-2-1: Randomly set the iteration value of the search target; or update the iteration value of the search target according to the iteration formula of the optimization algorithm; S4-2-2: Substitute the iterative value of the search target into the target optimization function to calculate the iterative fitness corresponding to the iterative value; S4-2-3: If the termination condition of the optimization algorithm is met, the iteration value of the search target corresponding to the highest historical iteration fitness during the entire iteration process is used as the target size parameter and the target shape parameter; otherwise, repeat steps S4-2-1 to S4-2-3.

[0016] According to the technical solution provided by the present invention, controlling the downward movement of the tooling according to the maximum downward movement speed includes: The tooling is controlled to move downwards within a water-filled vertical shaft at a first downward speed; the first downward speed is less than the maximum downward speed.

[0017] According to the technical solution provided by the present invention, the first downward movement speed is greater than 0.6 times the maximum downward movement speed.

[0018] The beneficial effects of this invention are as follows: To address the technical problem in existing technologies where the workpiece is difficult to maintain its position and prone to displacement due to disturbed water flow in deep-water, high-pressure environments during concrete sealing of water-filled shafts, resulting in uneven strength distribution of the sealing concrete structure, this invention provides an ultra-deep prefabricated underwater sealing workpiece and construction method for vertical shafts. This method uses a workpiece pre-embedded in the concrete sealing layer as the core carrier. The workpiece includes a support frame and a support assembly hinged to the support frame. The support assembly consists of a first support rod and a second support rod hinged at their ends. During construction, as the workpiece moves downwards within the water-filled shaft, the first and second support rods abut against the inner wall of the shaft or a reinforcing ring beam. Hydraulic hinges are installed between the first support rod and the support frame, and between the second support rod and the first support rod, to limit the maximum tilt angle. Through the aforementioned structure, the multi-point contact between the support components and the inner wall of the shaft provides reliable guidance and constraint for the tooling, effectively suppressing positional deviations caused by disturbed water flow. The hydraulic hinges automatically retract the support rods when they encounter obstacles such as the reinforcing ring beam, and automatically open them after passing, achieving automatic obstacle avoidance without power. Simultaneously, in conjunction with a speed control model constructed based on shaft dimensions and tooling parameters, the descent speed of the tooling can be precisely controlled. Therefore, this invention improves the descent stability and positioning accuracy of the tooling in deep-water, high-pressure environments, ensuring accurate pre-embedding of the tooling in the concrete seal without requiring personnel to dive. Attached Figure Description

[0019] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the tooling; Figure 2 This is a top view of the tooling; Figure 3 A top view of the tooling installed inside the shaft; Figure 4 This is the front view when both the first and second support rods are at their maximum tilt angles. Figure 5 A front view with the first support rod horizontally positioned and the second support rod at the second maximum tilt angle; Figure 6 This is the front view when both the first and second support rods are horizontally positioned. Figure 7 This is a schematic diagram showing the tooling installed inside the shaft. Figure 8 This is a schematic diagram showing the contact between the tooling and the reinforcing ring beam. Figure 9 This is a schematic diagram of the tooling passing through the reinforced ring beam; Figure 10 A schematic diagram showing the tooling installed on the bottom stratum inside the shaft; Figure 11 This is a schematic diagram when the tilt angle of the second support rod is too large. The components are: 1. Support frame; 2. First support rod; 3. Second support rod; 4. Reinforcing ring beam; 5. Outer ring; 6. Inner ring; 7. Connecting beam; 8. Traction rope; 9. Water; 10. Shaft; 11. Lifting beam; 12. Bottom stratum. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] Example 1 This invention provides an ultra-deep prefabricated vertical shaft underwater sealing fixture, referenced Figure 1 , Figure 2 , Figure 3 The tooling includes a bracket 1 and a support assembly hinged to the bracket 1; the support assembly is provided in at least three sets. The support assembly includes a first support rod 2 and a second support rod 3 whose ends are hinged to each other; the end of the first support rod 2 away from the second support rod 3 is hinged to the bracket 1; the hinge axes of the first support rod 2 and the second support rod 3 are both parallel to the horizontal direction. The support assembly has target size parameters and target shape parameters. When the tooling moves downward at the maximum downward speed in the vertical shaft 10 filled with water 9, the first support rod 2 and the second support rod 3 are used to slide against the inner wall of the vertical shaft 10 or the reinforcing ring beam 4 inside the vertical shaft 10.

[0023] The contact state between the tooling and the inner wall of shaft 10 includes: refer to Figure 7 The first support rod 2 remains horizontal, and the end of the second support rod 3 abuts against the inner wall of the shaft 10. refer to Figure 8 The first support rod 2 abuts against the reinforcing ring beam 4, causing it to tilt, while the second support rod 3 abuts against both the reinforcing ring beam 4 and the inner wall of the shaft 10. refer to Figure 9 The first support rod 2 is in the first maximum tilt angle state, and the second support rod 3 is only in contact with the reinforcing ring beam 4; refer to Figure 10The first support rod 2 and the second support rod 3 are attached to the bottom stratum 12. After construction is completed, the tooling is embedded in the concrete bottom seal.

[0024] Hydraulic hinges are installed between the first support rod 2 and the bracket 1, and between the second support rod 3 and the first support rod 2, to limit the first maximum tilt angle between the first support rod 2 and the bracket 1, and the second maximum tilt angle between the second support rod 3 and the first support rod 2 (the rotation axis is horizontal, and in this embodiment, the second maximum tilt angle is assumed to be 45 degrees). When the support rod touches the reinforcing ring beam 4 or an obstacle in the shaft 10, the hydraulic hinge is automatically triggered to retract when the force exceeds a preset threshold. After passing the reinforcing ring beam 4 or the obstacle, it automatically opens under the action of the hydraulic hinge. Its angle is pre-adjusted by the hydraulic hinge, and the movement angle of different support components remains consistent. The tooling descent process is controlled by the suspension equipment and requires no manual intervention. The support components can move during contact with obstacles, achieving automatic obstacle avoidance without power.

[0025] A lifting beam 11 is fixedly installed on the support 1. The lifting beam 11 is detachably connected to the traction rope 8 (for example, the end of the traction rope 8 is equipped with a gripper to hold the opening on the lifting beam 11). The traction rope 8, which is wound around the tool, is released through the suspension equipment, causing the tooling to move downwards into the water-filled vertical shaft 10. Because the support components of the tooling are hinged and have hydraulic hinges as limits, the relative movement of the two support rods results in various states. Three typical states are referenced below. Figures 4 to 6 .

[0026] refer to Figures 4 to 6 The shortest horizontal length of the first support rod 2 and the second support rod 3 is denoted as L3, the longest horizontal length of the first support rod 2 and the second support rod 3 is denoted as L4, the first maximum tilt angle of the first support rod 2 relative to the bracket 1 is denoted as c, and the second maximum tilt angle of the second support rod 3 relative to the first support rod 2 is denoted as d. The diameter of the bracket 1 is denoted as D, the length of the first support rod 2 is denoted as L1, and the length of the second support rod 3 is denoted as L2.

[0027] refer to Figures 7 to 10 This is a schematic diagram of the tooling moving downwards within the shaft 10, where the inner diameter of the shaft 10 is represented by D0, the width of the reinforcing ring beam 4 in the horizontal direction is represented by b, and the height difference between the reinforcing ring beam 4 and the bottom of the shaft is represented by H.

[0028] Example 2 During the process of the tooling moving down into the water-filled vertical shaft 10, the tooling does not shift position without significant disturbance to the water flow because multiple support components abut against the inner wall of the vertical shaft 10.

[0029] If the downward movement is too fast, the following will occur: the resistance from the water will push the first support rod 2 and the second support rod 3, thereby increasing the tilt angle of the first support rod 2 and the second support rod 3, which may cause the first support rod 2 and the second support rod 3 to no longer be able to abut against the inner wall of the shaft 10; at the same time, the excessively fast movement speed of the tooling itself will also bring about a disturbed water flow, which will affect the horizontal position of the tooling at the moment when the first support rod 2 and the second support rod 3 disengage from the inner wall of the shaft 10, ultimately causing a positional shift.

[0030] However, for any type of tooling, there is a corresponding maximum downward movement speed to keep the supporting components stable. But if the projected area of ​​the tooling on the horizontal plane is too large and its weight is too light, its corresponding maximum downward movement speed will be too small, which will prolong the time to control the downward movement of the tooling. In special cases, this may affect the construction progress.

[0031] Therefore, it is necessary to design a tooling with the maximum downward movement speed as large as possible; while ensuring that the tooling does not exceed the maximum downward movement speed during the downward movement process, and that the support components can always stably abut against the shaft 10 or the reinforcing ring beam 4, the time consumption of the tooling downward movement should be shortened.

[0032] refer to Figures 1 to 10 This invention provides a construction method for an ultra-deep prefabricated vertical shaft underwater bottom sealing fixture, applied to the fixture described in Example 1, comprising: S1: Obtain the vertical shaft dimension parameters; the vertical shaft dimension parameters include: vertical shaft inner diameter D0, reinforcing ring beam width b, and height difference H from the reinforcing ring beam to the bottom of the vertical shaft; S2: Determine the tooling dimension parameter constraints based on the shaft dimension parameters; the tooling dimension parameters include: the length of the first support rod L1 and the length of the second support rod L2. Step S2 includes: S2-1: The first constraint condition that the tooling dimensional parameters satisfy when the tooling passes through the reinforcing ring beam 4 inside the shaft 10 and abuts against the inner side wall of the shaft 10 or the reinforcing ring beam 4 inside the shaft 10. Specifically, the purpose of the first constraint is to enable the tooling to pass through the reinforcing ring beam 4, for multiple support components to simultaneously abut against the inner wall of the shaft 10, and for both the first support rod 2 and the second support rod 3 to fit against the surface of the bottom stratum 12. The first constraint condition is expressed as follows:

[0033] Where D0 is the inner diameter of the shaft. b To increase the width of the ring beam, HTo enhance the height difference between the ring beam and the bottom of the shaft, L1 is the length of the first support rod, L2 is the length of the second support rod, D is the diameter of the support, and c is the first maximum tilt angle of the first support rod relative to the support.

[0034] The purpose of the first constraint in the first constraint condition is to ensure that the tooling is in the narrowest possible horizontal position. When passing through the narrowest of the four reinforcing ring beams within shaft 10, it is possible to pass through them. ).

[0035] The purpose of the second constraint in the first constraint condition is to ensure that the first support rod 2 and the second support rod 3 are not too short, so that when the tooling is located at the position of the non-reinforced ring beam 4 inside the shaft 10, it can simultaneously abut against multiple positions on the inner sidewall of the shaft 10.

[0036] The purpose of the third constraint in the first constraint is to ensure that when the tooling is moved down to the bottom stratum 12 inside the shaft 10, the length of the first support rod 2 will not be too long to fit the surface of the bottom stratum 12.

[0037] The purpose of the fourth constraint in the first constraint is to ensure that the second support rod 3 is not too long and will not be restricted by the reinforcing ring beam 4 when it moves down to the bottom stratum 12 in the shaft 10, thus preventing it from fitting against the surface of the bottom stratum 12.

[0038] Based on the first constraint condition, the length range of the first support rod 2 and the second support rod 3 can be constrained to ensure that the tooling is in the narrowest state when passing through the reinforcing ring beam 4, and can effectively abut and fit when in contact with the inner wall of the shaft 10 and the bottom stratum 12, thereby ensuring the smoothness of the sinking process and the accuracy of the final positioning.

[0039] S2-2: Obtain the first conversion relationship between the support diameter D, the shaft inner diameter D0, and the reinforcing ring beam width b that satisfy the first constraint condition, and the first maximum tilt angle c of the first support rod 2 relative to the support. Generally, the first conversion relationship can be set according to actual needs, provided that the first constraint condition is met. It should be noted that during the tooling design phase, although the support diameter D can be used as a free variable in the calculation, if the support diameter is set too large, the distance between support 1 and the narrowest reinforcing ring beam 4 within the shaft 10 will be too small. Consequently, the selectable length range of the first support rod 2 and the second support rod 3 will be too small, increasing the probability that subsequent steps will fail to obtain parameters that meet the first constraint condition. If the support diameter is too small, the tooling will be more susceptible to positional shifts due to water flow disturbances.

[0040] In this embodiment, the first conversion relationship is set as: D=0.5D0-b; that is, the diameter D of the support is half of the spacing at the narrowest reinforcing ring beam 4 in the vertical shaft 10; thus, the support 1 is not too small and the first support rod 2 and the second support rod 3 have a sufficient range of length options, making it easier to obtain parameters that meet the first constraint condition in subsequent steps; at the same time, the tooling is not too easily affected by water flow.

[0041] S2-3: Substitute the first conversion relationship and the first maximum tilt angle into the first constraint condition to calculate the tooling size parameter constraint condition.

[0042] The tooling dimension parameter constraints are expressed as follows:

[0043] Where D0 is the inner diameter of the shaft. b To increase the width of the ring beam, H To enhance the height difference between the ring beam and the bottom of the shaft, L1 is the length of the first support rod, L2 is the length of the second support rod, and c is the first maximum tilt angle of the first support rod relative to the support frame.

[0044] In this embodiment, c=d=45°, which ensures that when the first support rod 2 and the second support rod 3 are in their shortest horizontal position, the second support rod 3 remains vertical, avoiding the situation where... Figure 11 The second support rod 3 shown cannot return to a horizontal state. In this embodiment, the maximum tilt angle is limited by a hydraulic hinge.

[0045] At this point, only L1 and L2 are free variables in the tooling dimension parameter constraints; the remaining parameters can be measured according to the actual situation.

[0046] S3: Construct a first function relating the tooling's downward movement speed to the tooling's size parameters and shape parameters; the tooling shape parameters include: the number of support components n, and the width of the support components k along the horizontal direction; Step S3 includes: S3-1: Based on the support diameter D, the shaft inner diameter D0 and the first conversion relationship, the volume V0 of the support and the projected area A0 of the support along the horizontal plane are calculated. Specifically, V0 and A0 need to be calculated based on the actual shape of the bracket 1. This embodiment uses... Figure 2 Taking the medium-shaped support 1 as an example, different shapes of support 1 need to be substituted into different formulas to complete the calculation; the calculation process of step S3-1 is a conventional mathematical method, and the calculation process for different shapes will not be described in detail.

[0047] refer to Figure 2In this embodiment, it is assumed that the cross-section of each part of the tooling is square. The bracket 1 includes an outer ring 5, an inner ring 6, and 12 connecting beams 7 that fix the outer ring 5 and the inner ring 6; the diameter of the inner ring is half the diameter of the outer ring. The horizontal width of the outer ring 5 and the horizontal width k0 of the inner ring 6 can be obtained through actual measurement. Therefore, after calculation and derivation, Figure 2 The volume V0 of the support frame and the projected area A0 of the support frame along the horizontal plane satisfy:

[0048] Substituting the first conversion relation, we get:

[0049] Where π is the mathematical constant pi. Therefore, all parameters in the formula are known, and the volume V0 of the support and the projected area A0 of the support along the horizontal plane can be directly calculated, facilitating subsequent calculations.

[0050] S3-2: Construct the force relationship equations for the tooling during its descent in water; Specifically, in order for the tooling to move downwards in the water so that its own weight can overcome buoyancy and resistance, the force relationship is expressed as:

[0051] Among them, F 浮 F is the buoyancy of the tool in the water. 阻 Let G be the resistance force encountered by the tooling as it moves in the water, and G be the total weight of the tooling. Based on common knowledge and the structure of the tooling in this embodiment, we can obtain:

[0052] Where G0 is the weight of the support frame, G1 is the weight of a set of support components, n is the number of support components, k is the width of the support component in the horizontal direction, and ρ0 is the density of the tooling. ρ The density of water, g For gravitational acceleration, C d The drag coefficient of the tool in water, v V1 is the volume of a set of support components, and A1 is the projected area of ​​a set of support components along the horizontal plane when they come into contact with the inner wall of the shaft.

[0053] In this embodiment, the drag coefficient C of the tooling in water is... d The value is obtained from actual measurements or set to 1.2 to 1.5 based on empirical values, with 1.3 being preferred.

[0054] It should be noted that: based on the above formula, A1 and v The values ​​are inversely proportional, and the size of A1 varies depending on the tooling's state. The goal is to find the maximum value that satisfies the first constraint in all states.v The maximum value of A1 needs to be substituted into the calculation. In this embodiment, when A1 reaches its maximum value, it corresponds to the state when the support component abuts against the inner wall of the shaft 10, referring to... Figure 7 Therefore, the length of a set of support components is expressed as... .

[0055] S3-3: Substitute the volume V0 of the support, the projected area A0 of the support along the horizontal plane, the tooling size parameters, and the tooling shape parameters into the force relationship to construct the first function.

[0056] Based on the preceding text, the force relationship after substituting into the calculation only contains... v , n, k, L1, L2 are free variables, and the remaining parameters are known. Thus, the first function representing the relationship between the tooling's downward movement speed and the tooling's size and shape parameters can be derived.

[0057] The first function is represented as:

[0058] After obtaining the first function, n, k, L1, and L2 can be used as search targets, and optimization algorithms can be used to search for the function that satisfies the given condition. v The maximum values ​​of n, k, L1, and L2 are obtained. Then, the obtained n, k, L1, and L2 are used as the target size and target shape parameters, and the maximum value is selected. v To determine the maximum downward movement speed, please refer to the following steps: S4: Calculate the maximum downward movement speed, target size parameters, and target shape parameters of the tooling using the first function and the tooling size parameter constraints, including: S4-1: Set the target optimization function according to the first function; set the second constraint condition according to the tooling size parameter constraint condition; Specifically, the objective optimization function is a weighted sum of the first function and the tooling preparation cost:

[0059] in, f Let Q be the fitness represented by the objective optimization function, Q be the tooling preparation cost, Q0 be the scaffold preparation cost, Q1 be the preparation cost of a set of support components, w1 and w2 be the weights, and q be the cost per unit volume of the support component.

[0060] In this embodiment, fitness and v Positively correlated with, and negatively correlated with, tooling preparation cost; therefore, the value of the search objective obtained using the objective optimization function can make v Make it as large as possible, while ensuring that the tooling preparation cost is as low as possible.

[0061] The tooling manufacturing cost is the sum of the manufacturing cost of bracket 1 and the manufacturing cost of multiple support components. Since the structure, shape, and size of bracket 1 are designed to be fixed according to the dimensions of the shaft 10 in this embodiment, its manufacturing cost can also be set to a fixed value based on experience. The manufacturing cost of a set of support components can also be calculated based on the cost per unit volume q. After obtaining n, k, L1, and L2 in each iteration, the final tooling manufacturing cost can be calculated.

[0062] In some implementations, w1=0.8 and w2=0.2 can make the optimization algorithm more inclined to guarantee... v Maximize the size while minimizing tooling preparation costs; conversely, minimize them.

[0063] In some implementations, the second constraint includes tooling dimensional parameter constraints, and further includes: The range of the number of supporting components is: 3 ≤ n ≤ πD / k; Width range of first support rod 2 and second support rod 3: lower limit of width k min ≤k≤width limit k max ; The number of support components is greater than 3 to ensure support stability, and less than πD / k is set to take into account the production cost of the tooling. On the other hand, since only a limited number of support components can be installed on the outer edge of the bracket 1, the number of support components exceeding the installation limit has no practical construction significance. Therefore, this range is set to ensure that the obtained search target meets the needs of the real scenario.

[0064] Width lower limit k min Set the minimum width (e.g., 5cm) that the support component can provide sufficient support; maximum width k max Set to 0.1D, which is one-tenth of the support diameter D.

[0065] Setting a lower width limit ensures sufficient support strength for the supporting components, while setting an upper width limit reduces the search range. Excessive width significantly increases water resistance, making it harder to achieve greater adaptability. Therefore, excluding excessively wide widths allows the optimization algorithm to preemptively eliminate obviously unsuitable cases, making it easier to find the target size and shape parameters.

[0066] S4-2: Based on the objective optimization function and the second constraint, using the tooling size parameters and tooling shape parameters as search targets, an optimization algorithm is used to search for the target size parameters and target shape parameters that maximize the tooling's downward movement speed and minimize the cost, including: S4-2-1: Randomly set the iteration value of the search target; or update the iteration value of the search target according to the iteration formula of the optimization algorithm; Specifically, optimization algorithms can include particle swarm optimization, genetic algorithms, etc.

[0067] Before the first iteration, the iteration value of the search target is randomly set, that is, the search target is randomly selected within the range of the second constraint condition.

[0068] During the iteration process, the iteration value obtained from the previous iteration is substituted into the iteration formula of the optimization algorithm to calculate the value of the search target within the range of the second constraint condition in the next iteration, thus obtaining the iteration value of the search target in this iteration.

[0069] S4-2-2: Substitute the iterative value of the search target into the target optimization function to calculate the iterative fitness corresponding to the iterative value; S4-2-3: If the termination condition of the optimization algorithm is met, the iteration value of the search target corresponding to the highest historical iteration fitness during the entire iteration process is used as the target size parameter and the target shape parameter; otherwise, repeat steps S4-2-1 to S4-2-3.

[0070] Taking genetic algorithms as an example, the settings required to implement the above steps include: The maximum number of iterations is 200 generations, the population size is set to 50 to 200, the crossover probability is set to 0.8 to 0.9, the mutation probability is set to 0.01 to 0.1, and the termination condition is set to reach the maximum number of iterations or the historical maximum value of the iteration fitness increases by no more than 1% for 10 consecutive generations.

[0071] S4-3: The downward movement speed corresponding to the target size parameter and the target shape parameter is taken as the maximum downward movement speed.

[0072] The tooling size and shape parameters obtained in the above steps are the optimal solutions that maximize the downward movement speed. The corresponding downward movement speed is the maximum possible speed among all feasible parameter combinations. Using this speed as the maximum downward movement speed provides a clear upper limit for controlling the tooling sinking rate during subsequent construction, ensuring that the tooling sinks stably and does not deviate during the sinking process.

[0073] S5: Prepare the tooling as described in Example 1 according to the target size parameters and target shape parameters; S6: The tooling is placed in the vertical shaft 10 filled with water 9, and the tooling is controlled to move down in the vertical shaft 10 according to the maximum downward movement speed; The tooling is controlled to move downwards at a first downward speed within a vertical shaft 10 filled with water 9; the first downward speed is less than the maximum downward speed but greater than 0.6 times the maximum downward speed.

[0074] Specifically, after obtaining the maximum downward speed, controlling the tool to move at a speed lower than the maximum downward speed reduces the resistance of the tool in water 9, thereby reducing the disturbance of the water flow. At the same time, the support components on the tool abut against multiple positions on the inner wall of the shaft 10, which can significantly reduce the probability of the tool shifting due to the influence of water flow during its downward movement in water 9.

[0075] In cases of tight construction schedules, the equipment can be moved at maximum speed in the water to reach the bottom stratum 12 as quickly as possible to complete the concrete sealing construction.

[0076] For the reasons mentioned above, the solution in this embodiment can ensure that the tooling is accurately positioned in the predetermined location and embedded in the concrete bottom seal, thereby ensuring the balance of structural strength of each part of the bottom seal concrete.

[0077] S7: Construct a concrete seal for the bottom of the shaft 10 and embed the tooling in the concrete seal.

[0078] Based on the above, the overall construction process includes: I. Final Settling Acceptance and VSM Initial Cleaning and Slurry Replacement After the shaft is lowered to the design elevation, the elevation, verticality, and ellipticity of the shaft body are immediately re-measured, a final settlement record is generated and submitted for inspection; if the cumulative self-sinking within 8 hours is ≤10mm, the pipe section lifting device is locked, thixotropic mud is injected, the wellhead limit device is checked, and the final settlement is confirmed to be stable.

[0079] The VSM milling arm was used to trim and over-excavate the base, with an over-excavation width of 50mm, ensuring that the bottom of the cutting edge was covered with sealing concrete. Milling was repeated clockwise according to the excavation width, and slag was pumped out. A D-GPS unmanned surface vessel, in conjunction with a multi-beam MBES ultrasonic dual-frequency echo reflector and a measuring rope, was used to detect the elevation and flatness of the base, forming a uniform pot-shaped base. The VSM slurry removal system was simultaneously activated for the first slurry replacement, and clean water was continuously injected into the wellhead.

[0080] The VSM main unit is lifted to the wellhead using the main unit lifting and recovery track inside the tunnel lining segment. Modifications are then made to the cutting arm's slurry inlet and outlet pipelines, flushing pipes, and grating plates, and a wall-brushing fixture is installed. This fixture mainly consists of a brush plate and a flushing system. The brush plate uses a hydraulic and sliding wheel assembly with two degrees of freedom adjustable angles and a 70cm... 1cm A 1.5m Q355b steel plate is used to position the wire brush. The steel plate is then welded and fixed to the cutting drum. Before fixing, the corresponding cutting teeth must be removed. The flushing system consists of an adjustable angle gradually telescopic nozzle and a multi-stage booster pump, which is fixed around or on both sides of the brush plate. Each nozzle is connected to the P2.1 slurry pump plug plate by a high-pressure water pipe. At the same time, the slurry inlet pipeline is changed to the slurry outlet pipeline, and a multi-stage booster pump is added to provide flushing pressure using backflushing. Before positioning the tooling in the well, the nozzles are fixed to the brush plate. The brush plate must be cut to the outer arc surface of the drum and positioned parallel to the well wall.

[0081] The VSM main unit was lowered back to the design bottom elevation, and the well wall within the sealing concrete area was flushed and brushed by switching clockwise and counterclockwise cycles. The FIFISH real-time underwater robot was used for inspection and acceptance. The relative density of the base mud was tested to see if it dropped to below 1.08 to 1.10 g / cm³, the sand content was ≤8%, and the sediment thickness was ≤100 mm. After passing the test, the VSM main unit was recovered.

[0082] II. Wellbore sectional flushing and vacuum mud suction secondary cleaning The well wall is flushed in two sections: For the well wall above the connecting beam: a truck crane is used to suspend the wall-scrubbing machine, and high-pressure water is used to clean from top to bottom, section by section. The working width of a single section is 1.0m, and the effective spray height is 50 to 60cm. An underwater robot assists in checking the cleanliness.

[0083] For hard-to-clean areas such as the cutting edge, bottom of the ring beam, and groove of the support shoe: a bent-head flushing and suction mud machine is used, which has the functions of high-pressure water jetting and mud removal. It can specifically flush mud cakes in the inside and outside corners, and discharge the mixed slag outside the well while flushing and suctioning.

[0084] After the well wall is cleaned to a satisfactory standard, an air suction machine is used to perform full-area vacuum suction of the base. The suction pipe is kept 15 to 50 cm away from the mud surface. The machine is moved frequently to ensure a good mud removal rate. At the same time, a second mud replacement is carried out, and clean water is continuously added to the wellhead to keep the water level in the well 0.5 to 1.0 m higher than the groundwater level.

[0085] After the mud replacement is completed, the following test indicators are required: relative density of mud 1.08 to 1.10 g / cm³, sand content ≤5%, sediment thickness ≤100 mm. After the underwater robot passes the full-area inspection, the process proceeds to the next stage.

[0086] III. Proceeding steps S1 to S6, during which: The double-layer arc-shaped tooling is laid out using 50×5mm square steel pipes welded together. The diameters of the inner ring (6mm) and outer ring (5mm) maintain a safe distance from the ring beam. Radial movable arms are set on the outer edge, with each arm being 3.0 to 5.0m long. They are connected by hydraulic limit hinges and can automatically retract when they touch an obstacle and automatically open after passing through, adapting to the ring beam avoidance requirements.

[0087] The bidirectional warp-knitted polyester geogrid is tied to the tooling on the ground at the wellhead with No. 4 iron wire. A steel bar counterweight is added to the inner ring of the tooling to counteract the buoyancy of the mud.

[0088] The lifting device is lifted by a crawler crane and lowered slowly in the center, maintaining stability and preventing eccentricity during the process; the boom automatically retracts when it touches the ring beam and automatically opens and resets after passing through the ring beam area.

[0089] Use an underwater robot to check the flatness of the grille, confirming that there is no displacement, curling, or stacking, and that the edges and corners are properly covered.

[0090] After the tooling is moved to the designated position, proceed with S7, including: The suspension equipment is automatically disconnected from the hoisting beam 11; then the concrete sealing construction is carried out: To address the complex internal structure and actual site layout of the vertical shaft, a "tiered inner and outer ring, four-zone symmetrical" guide pipe injection system was designed. Fourteen Φ273mm guide pipes are arranged in a ring around the entire well. Four guide pipes are set in the inner ring to cover the inner area of ​​the ring beam, and ten guide pipes are set in the outer ring to cover the outer area of ​​the ring beam. The spacing between the guide pipes is 2.85 to 3.25m. The spacing and number need to be considered in advance to avoid the internal structure of the shaft. The entire shaft is divided into 4 work zones, each equipped with 1 pump truck, 1 crane, and 4 tank trucks, with clear responsibilities. The initial grouting follows the principle of "inner first, outer second, symmetrical intervals, and avoiding mud heave". The initial grouting of the 4 inner ring pipes is completed first, and then the initial grouting of the 10 outer ring pipes is completed symmetrically in a clockwise direction. Both the initial grouting and normal grouting adopt a continuous operation mode. During normal grouting, the burial depth of the guide pipe is controlled at 1.5 to 3.5m, and the grouting interval of the same guide pipe is ≤1 hour. The guide pipe is raised and lowered every 30 minutes to prevent blockage. It is equipped with 24 flat-bottomed measuring hammers to monitor the concrete surface elevation at a certain frequency, dynamically adjust the grouting rhythm, and ensure that the concrete surface rises evenly with a height difference of ≤0.5m.

[0091] When the bottom sealing concrete is poured to a height of 0.5 to 1.0m from the design top elevation, the concrete surface elevation within the flow radius of each guide pipe is checked using a cloud platform. Special attention is paid to the intersection of the guide pipe's effective radius, concrete components, and the area surrounding the foundation pit. Based on the measurement results, additional grouting is performed on guide pipes near points with lower elevations, and the flatness of the bottom sealing surface is controlled. The bottom sealing construction is completed once all measuring points meet the allowable elevation deviation requirements. Subsequent water curing continues until the concrete reaches its design strength.

[0092] IV. Layered Pumping and Acceptance After the bottom concrete has set, the first pumping is carried out until the groundwater level is 2 meters below the elevation. The pumping stops thereafter. The deformation of the well body, the rise of the water level, and the leakage of the joints are continuously monitored. Once the data is stable, the construction of the upper cast-in-place section can proceed.

[0093] After the bottom sealing concrete reaches 100% of the design strength and passes the quality acceptance, the water is pumped in layers: each pumping depth is ≤2m, pumping is stopped and left to stand for 1 hour, and indicators such as wellhead settlement, convergence, and groundwater level are monitored. Only after all indicators are stable can the next round of pumping continue.

[0094] After pumping water up to the top surface of the bottom sealing concrete, a comprehensive inspection is conducted on the quality of the bottom sealing surface, leakage, and adhesion to the well wall. Once the inspection is passed, the subsequent bottom slab construction can proceed.

[0095] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention is not limited to the specific combination of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A deep prefabricated underwater bottom sealing fixture for vertical shafts, characterized in that, The tooling includes a bracket (1) and a support assembly hinged to the bracket (1); the support assembly is provided in at least three sets; The support assembly includes a first support rod (2) and a second support rod (3) with their ends hinged together; the end of the first support rod (2) away from the second support rod (3) is hinged to the bracket (1); the hinge axes of the first support rod (2) and the second support rod (3) are both parallel to the horizontal direction. Hydraulic hinges are installed between the first support rod (2) and the bracket (1), and between the second support rod (3) and the first support rod (2), to limit the first maximum tilt angle between the first support rod (2) and the bracket (1), and the second maximum tilt angle between the second support rod (3) and the first support rod (2); The support assembly has target size parameters and target shape parameters. When the tooling moves downward at the maximum downward speed in the vertical shaft (10) filled with water (9), the first support rod (2) and the second support rod (3) are used to slide against the inner wall of the vertical shaft (10) or the reinforcing ring beam (4) inside the vertical shaft (10).

2. A construction method for an ultra-deep prefabricated vertical shaft underwater bottom sealing fixture, characterized in that, include: S1: Obtain the vertical shaft dimension parameters; The vertical shaft dimensions include: the inner diameter of the vertical shaft, the width of the reinforcing ring beam, and the height difference between the reinforcing ring beam and the bottom of the vertical shaft. S2: Determine the tooling size parameter constraints based on the shaft size parameters; S3: Construct a first function relating the tooling's downward movement speed to the tooling's dimensional parameters and shape parameters; the tooling's dimensional parameters include: the length of the first support rod and the length of the second support rod; the tooling's shape parameters include: the number of support components and the width of the support components in the horizontal direction; S4: Calculate the maximum downward movement speed, target size parameters, and target shape parameters of the tooling using the first function and the tooling size parameter constraints; S5: Prepare the tooling as described in claim 1 according to the target size parameters and target shape parameters; S6: The tooling is placed in a water-filled vertical shaft, and the tooling is controlled to move downward in the vertical shaft according to the maximum downward movement speed; S7: Construct a concrete seal for the bottom of the shaft and embed the tooling in the concrete seal.

3. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 2, characterized in that, S2: Determine the tooling dimension parameter constraints based on the shaft dimension parameters, including: S2-1: Obtain the first constraint condition that the tooling dimensional parameters satisfy when the tooling passes through the reinforcing ring beam inside the shaft and abuts against the inner wall of the shaft or the reinforcing ring beam inside the shaft; the first constraint condition includes: the tooling can pass through the reinforcing ring beam, multiple support components can simultaneously abut against the inner wall of the shaft, and both the first support rod and the second support rod can fit against the surface of the bottom stratum. S2-2: Obtain the first conversion relationship between the support diameter, the shaft inner diameter and the width of the reinforcing ring beam that satisfy the first constraint condition, and the first maximum tilt angle of the first support rod relative to the support; S2-3: Substitute the first conversion relationship and the first maximum tilt angle into the first constraint condition to calculate the tooling size parameter constraint condition.

4. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 3, characterized in that, The tooling dimension parameter constraints are expressed as follows: Where D0 is the inner diameter of the shaft. b To increase the width of the ring beam, H To enhance the height difference between the ring beam and the bottom of the shaft, L1 is the length of the first support rod, L2 is the length of the second support rod, and c is the first maximum tilt angle of the first support rod relative to the support frame.

5. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 4, characterized in that, S3: Construct the first function relating the tooling descent speed to the tooling dimension parameters and the tooling shape parameters, including: S3-1: Based on the support diameter, the shaft inner diameter and the first conversion relationship, calculate the volume of the support and the projected area of ​​the support along the horizontal plane. S3-2: Construct the force relationship equations for the tooling during its descent in water; S3-3: Substitute the volume of the support, the projected area of ​​the support along the horizontal plane, the tooling size parameters, and the tooling shape parameters into the force relationship to construct the first function.

6. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 5, characterized in that, The first function is represented as: in, v Let ρ be the downward velocity of the tooling, ρ0 be the density of the tooling, ρ be the density of water, g be the acceleration due to gravity, V0 be the volume of the support, A0 be the projected area of ​​the support along the horizontal plane, and C be the velocity of the tooling. d Let n be the resistance coefficient of the tooling in water, n be the number of support components, and D be the diameter of the support.

7. The construction method of an ultra-deep prefabricated vertical shaft underwater bottom sealing fixture according to claim 2, characterized in that, S4: Calculate the maximum downward movement speed, target size parameters, and target shape parameters of the tooling using the first function and the tooling size parameter constraints, including: S4-1: Set the target optimization function according to the first function; set the second constraint condition according to the tooling size parameter constraint condition; S4-2: Based on the target optimization function and the second constraint, with the tooling size parameters and tooling shape parameters as the search targets, the optimization algorithm is used to search for the target size parameters and target shape parameters that maximize the tooling's downward movement speed and minimize the cost. S4-3: The downward movement speed corresponding to the target size parameter and the target shape parameter is taken as the maximum downward movement speed.

8. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 7, characterized in that, S4-2: Based on the objective optimization function and the second constraint, using the tooling size parameters and tooling shape parameters as search targets, an optimization algorithm is used to search for the target size parameters and target shape parameters that maximize the tooling's downward movement speed and minimize the cost, including: S4-2-1: Randomly set the iteration value of the search target; or update the iteration value of the search target according to the iteration formula of the optimization algorithm; S4-2-2: Substitute the iterative value of the search target into the target optimization function to calculate the iterative fitness corresponding to the iterative value; S4-2-3: If the termination condition of the optimization algorithm is met, the iteration value of the search target corresponding to the highest historical iteration fitness during the entire iteration process is used as the target size parameter and the target shape parameter; otherwise, repeat steps S4-2-1 to S4-2-3.

9. The construction method of an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 2, characterized in that, Controlling the tooling to move downward within the shaft according to the maximum downward speed includes: The tooling is controlled to move downwards within a water-filled vertical shaft at a first downward speed; the first downward speed is less than the maximum downward speed.

10. A construction method for an ultra-deep prefabricated vertical shaft underwater sealing fixture according to claim 9, characterized in that, The first downward movement speed is greater than 0.6 times the maximum downward movement speed.

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