A sealing and waterproof structure of a repeater in pipe jacking construction and a pipe jacking construction method

Abstract

The application discloses a sealing waterproof structure of a repeater in pipe jacking construction and a pipe jacking construction method, belongs to the technical field of waterproofing of repeaters in pipe jacking construction, and aims to solve the technical problem that the sealing performance of a sealing ring of an existing repeater is invalid due to abrasion and the lack of real-time monitoring means for the abrasion state, and the technical solution is characterized in that: the sealing waterproof structure comprises a shell, a front pipe joint and a rear pipe joint, and an annular sealing space is formed between the shell and the rear pipe joint; a multistage gradient sealing assembly is arranged in the annular sealing space, the assembly comprises at least two sealing rings; a push compensation assembly is arranged on the axial side of at least part of the sealing rings, the push compensation assembly comprises a push piece and a driving mechanism, the driving mechanism is in transmission connection with the push piece, the push piece is in abutment with the axial end face of the sealing ring, the sealing ring is connected with an abrasion monitoring assembly, and a control unit is further arranged, which is used for executing abrasion evaluation and judgment according to the abrasion amount and controlling the action of the driving mechanism.

Description

Technical Field

[0001] This invention belongs to the field of waterproofing technology for intermediate stations in pipe jacking construction, specifically a sealing and waterproofing structure for intermediate stations in pipe jacking construction and a pipe jacking construction method. Background Technology

[0002] Pipe jacking technology is a non-excavation construction technique adopted when excavation is not feasible under existing conditions. The core of it is to use jacks in the working shaft to push prefabricated pipes into the soil layer section by section, while the excavator head digs in, removes slag from inside the pipe, and finally reaches the receiving shaft, thus achieving the "underground needle threading" that crosses obstacles such as roads, rivers, and buildings.

[0003] After the pipe jacking has advanced a certain distance, the friction between the pipe and the stratum will prevent the jacks from continuing to advance, and an intermediate station needs to be set up. Even with the lubrication and resistance reduction of the thixotropic mud sleeve, an intermediate station is still needed because the function of the thixotropic mud sleeve is to reduce resistance, not to eliminate it. Small resistances accumulate into large resistances.

[0004] The relay room is equivalent to a retractable pipe section. Jacks are installed inside the relay room. When the jacks in the working shaft can no longer push forward, the jacks in the working shaft stop pushing forward but cannot retract. At this time, the jacks in the relay room push forward the first section of the pipe. After pushing it into place, they stop pushing forward and keep it in a relaxed state. Then the jacks in the working shaft push forward the second half of the pipe. They push forward alternately in this way.

[0005] Because the construction of the relay room involves alternating jacking, water leakage is very likely to occur, especially over long distances or when the groundwater pressure is high. If water leakage occurs in the relay room, it is extremely difficult to deal with.

[0006] Existing technology CN111503366A discloses a curved pipe jacking relay station and its construction method, including a shell, a front special pipe, a rear special pipe, hydraulic jacks, sealing rings, a front support ring, and a rear support ring. The shell is a steel cylinder with a smooth surface. The front special pipe is welded to the shell as a whole. The hydraulic jack is fixed to the shell by welding with steel clamps. The rear special pipe is connected to the shell by sealing rings, forming a radially adjustable sealing space. Two sealing rings are provided, with four grease holes in the middle for injecting lubricating grease to reduce wear on the sealing rings during jacking. Four grouting holes are also provided on the pipe section for synchronous grouting during jacking to reduce jacking resistance.

[0007] The aforementioned existing technology uses two water-stop sealing rings to prevent leakage even as the housing moves back and forth over them. However, these sealing rings can wear down during use due to factors such as long jacking distance and sand friction, which may lead to sealing performance failure and subsequently cause problems such as soil loss, ground settlement, and increased pipeline friction resistance. Summary of the Invention

[0008] The purpose of this invention is to provide: A sealing and waterproofing structure for intermediate stations during pipe jacking construction, and a pipe jacking construction method, are provided to solve the technical problem of insufficient waterproofing performance of intermediate stations in existing technologies. (1) In existing pipe jacking construction, only two sealing rings are usually installed in the intermediate station. During the long-distance jacking process, the sealing rings are worn due to the continuous reciprocating motion of the pipe and the friction of sand particles. The sealing performance gradually fails as the wear deepens, which in turn leads to engineering safety problems such as groundwater seepage into the pipe, soil loss and increased frictional resistance of the outer wall of the pipe. (2) Existing technologies lack real-time detection methods for the wear state of the sealing ring. The amount of wear on the sealing ring cannot be grasped in time. Construction personnel cannot take preventive maintenance measures before the seal fails, nor can they actively adjust the sealing pressure according to the wear state to achieve compensatory sealing, which poses a significant engineering safety hazard.

[0009] Terminology Explanation: Unless otherwise defined, all technical terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this subject matter pertains. Unless otherwise stated, all patents, patent inventions, and disclosures cited throughout this document are incorporated herein by reference in their entirety. Where multiple definitions exist for terms herein, the definitions provided in this chapter shall prevail.

[0010] It should be understood that the above brief description and the following detailed description are exemplary and for illustrative purposes only, and do not limit the subject matter of the invention in any way. In this invention, the singular is used in conjunction with the plural unless otherwise specifically stated. It should also be noted that, unless otherwise stated, the use of “or” or “or” means “and / or”. Furthermore, the use of the term “comprising” and other forms such as “including,” “containing,” and “contains” are not limiting.

[0011] Unless specifically defined herein, the use of various commercially available products herein employs standard techniques. For example, they may be implemented using the manufacturer's instructions for use, or in accordance with methods known in the art or the description of this invention. The techniques and methods described herein can generally be implemented according to conventional methods well known in the art, based on the descriptions in the various general and more specific documents cited and discussed in this specification.

[0012] The terms “optional / arbitrary” or “optionally / arbitrarily” mean that the event or situation described below may or may not occur, including both the occurrence and non-occurrence of the event or situation.

[0013] In a first aspect, the present invention provides: A sealing and waterproof structure for a relay station in pipe jacking construction includes a shell, a front pipe section, and a rear pipe section. The front pipe section is fixedly connected to the shell, and the rear pipe section is inserted into the shell, forming an annular sealing space between the shell and the rear pipe section. The annular sealing space is provided with a multi-stage gradient sealing assembly, which includes at least two sealing rings. The radial dimension of the outer sealing ring is larger than that of the inner sealing ring. The outer sealing ring is axially close to the open end of the annular sealing space, and the inner sealing ring is axially close to the closed end of the annular sealing space. At least a portion of the sealing ring has a push-compensation component on its axial side. The push-compensation component includes a pusher and a drive mechanism. The drive mechanism is connected to the pusher. The pusher abuts against the axial end face of the sealing ring to apply axial compressive force to the sealing ring to achieve active compensation sealing. The sealed and waterproof structure is also connected to a wear monitoring component, which is used to detect the amount of wear on the sealing ring. The wear monitoring component is connected to a control unit, which is electrically connected to the wear monitoring component and the drive mechanism. The control unit is used to perform wear assessment and judgment based on the amount of wear and control the operation of the drive mechanism, thereby forming a closed-loop control system for real-time monitoring and active compensation of the sealing status.

[0014] Furthermore, the multi-stage gradient sealing assembly includes a first sealing ring, a second sealing ring, a third sealing ring, and a fourth sealing ring. The first and second sealing rings are outer sealing rings, and the third and fourth sealing rings are inner sealing rings. The radial dimensions of the first and second sealing rings are both larger than those of the third and fourth sealing rings. The first, second, third, and fourth sealing rings are arranged sequentially along the axial direction within the annular sealing space. By setting four sealing rings with different radii, a gradient waterproofing system with an outer main seal and an inner backup seal is formed, significantly improving the reliability of the sealing structure.

[0015] Furthermore, a grease injection hole is provided on the housing wall between the first sealing ring and the second sealing ring. The grease injection hole is used to inject lubricating grease between the first sealing ring and the second sealing ring. By injecting lubricating grease, the friction and wear of the outer sealing ring during the jacking process can be effectively reduced, and the wear rate of the outer sealing ring can be slowed down.

[0016] Furthermore, the driving mechanism is a hydraulic cylinder, and the pressing component is a push plate. The push plate is disposed on the axial side of the sealing ring and fits against the end face of the sealing ring. The hydraulic cylinder is fixed to the inner wall of the rear pipe section. The piston rod of the hydraulic cylinder is fixedly connected to the push plate through a connecting rod. When the piston rod extends axially, the push plate presses the corresponding sealing ring axially. The structure of the hydraulic cylinder driving the push plate can precisely control the axial compressive force applied to the sealing ring, realizing active compensation sealing.

[0017] Furthermore, each of the first, second, third, and fourth sealing rings is equipped with a push plate and a hydraulic cylinder. The four hydraulic cylinders are independently electrically connected to the control unit, which independently controls the movement of the corresponding hydraulic cylinder based on the wear level of each sealing ring. Each sealing ring is equipped with an independent hydraulic cylinder and push plate, enabling precise and independent compensation control for each sealing ring, adapting to the differentiated compensation needs of different sealing rings at different wear stages.

[0018] Furthermore, the control unit is electrically connected to the proportional control valve of the hydraulic cylinder. The proportional control valve adjusts the hydraulic pressure of the hydraulic cylinder according to the control signal output by the control unit. The control unit outputs a control signal to the proportional control valve according to the wear amount of the corresponding sealing ring. Continuous adjustment of the hydraulic pressure is achieved through the proportional control valve, making the squeezing force applied by the push plate to the sealing ring adapt to the wear amount, thus realizing adaptive compensation control.

[0019] Furthermore, the wear monitoring component is a capacitance detection circuit; the sealing ring is composed of a conductive layer and an insulating layer, with the conductive layer and the insulating layer coaxially arranged, and the sealing ring itself forming a capacitor element; a capacitance detection circuit is provided on the inner wall of the rear pipe section, and the capacitance detection circuit is electrically connected to the conductive layer and the inner wall of the rear pipe section through wires, for real-time acquisition of the capacitance value of the sealing ring and conversion of the capacitance value into the wear amount. When the sealing ring wears, the thickness of the insulating layer decreases, resulting in an increase in the capacitance value. By detecting the change in capacitance value, the wear amount of the sealing ring can be calculated in real time, without the need for additional external sensors, resulting in a high degree of structural integration.

[0020] Furthermore, the conductive layer is located radially outside the sealing ring, and the insulating layer is located radially inside the conductive layer; the capacitance detection circuit calculates the wear amount of the sealing ring based on the change in capacitance value. The conductive layer's radially outer location ensures preferential contact with the friction medium, and the wear direction corresponds to the direction of capacitance change, guaranteeing the accuracy of the wear amount calculation.

[0021] Furthermore, the capacitance detection circuit calculates the wear of the sealing ring in real time. When the wear exceeds a corresponding warning threshold, the capacitance detection circuit sends a remaining life warning signal to the control unit, which then triggers an alarm in response. This remaining life warning function allows construction managers to anticipate the need for sealing ring replacement, effectively preventing engineering safety accidents caused by seal failure.

[0022] Furthermore, the wear assessment judgment performed by the control unit includes single-turn independent threshold judgment and multi-turn fusion judgment; In the single-ring independent threshold determination, the control unit compares the wear amount of each sealing ring with the corresponding single-ring wear threshold. When the wear amount of any sealing ring exceeds the corresponding single-ring wear threshold, the control unit outputs a drive command to the drive mechanism corresponding to that sealing ring. In the multi-ring fusion determination, the control unit performs a weighted summation of the wear data of each sealing ring to obtain a fusion value. When the fusion value exceeds a preset fusion threshold, the control unit outputs a drive command to all drive mechanisms. Single-ring independent threshold determination can promptly trigger compensation actions for severely worn sealing rings, while multi-ring fusion determination comprehensively reflects the overall wear state of the sealing structure. The combination of the two determination methods effectively improves the accuracy and reliability of wear assessment.

[0023] Preferably, in the multi-ring fusion determination, the weighting coefficient corresponding to the outer sealing ring in the control unit is higher than the weighting coefficient corresponding to the inner sealing ring. The outer sealing ring directly bears the groundwater pressure and friction, and its wear state has a more significant impact on the overall sealing performance. Assigning a higher weighting coefficient is consistent with the design logic of prioritizing the protection of the outer sealing ring, thus improving the rationality of the fusion determination result.

[0024] The present invention also provides a pipe jacking construction method, comprising: Step 1: Install the repeater station; Step 2: Monitor the wear of the sealing ring in real time during the jacking process; Step 3: Perform a single-lap independent threshold determination and trigger the corresponding compensation action; Step 4: After the hydraulic cylinders corresponding to the third and fourth sealing rings are both started, perform multi-ring fusion judgment and trigger the overall compensation strategy; Step 5: Respond to remaining life warnings and schedule maintenance.

[0025] The steps include setting up a main jacking jack in the working shaft, setting up a relay room in the pipeline, and alternately jacking the preceding and following sections of the pipeline. During the pipe jacking process, wear sensors embedded in each sealing ring of the multi-stage gradient sealing assembly are used to collect wear data of each sealing ring in real time. The control unit performs wear assessment and judgment based on the wear data. According to the judgment result, the driving mechanism drives the pushing component to apply extrusion force to the corresponding sealing ring to achieve active compensation sealing.

[0026] Furthermore, the wear assessment and determination specifically includes: the control unit compares the wear amount of each sealing ring with the corresponding single-ring wear threshold. When the wear amount of any sealing ring exceeds the corresponding single-ring wear threshold, the control unit outputs a drive command to the drive mechanism corresponding to the sealing ring, and the drive mechanism drives the corresponding pusher to apply a compressive force to the sealing ring.

[0027] The control unit performs a weighted summation of the wear data of each sealing ring to obtain a fusion value. When the fusion value exceeds a preset fusion threshold, the control unit outputs a drive command to all drive mechanisms, and each drive mechanism drives the corresponding pressing component to apply pressure to the corresponding sealing ring. By combining single-ring threshold determination with multi-ring fusion determination in the construction control method, intelligent monitoring and adaptive control of the sealing status during pipe jacking construction are achieved.

[0028] The present invention has at least the following beneficial effects: First, sealing reliability is significantly improved. By setting up multi-level gradient sealing rings with a larger outer radial dimension and a smaller inner radial dimension, multiple waterproof barriers are constructed. Even if the sealing performance of the outer sealing ring decreases due to wear, the inner sealing ring can take over the sealing function in time, effectively avoiding water leakage accidents caused by the failure of a single sealing ring, and significantly improving the sealing reliability of the relay station under long-distance and high water pressure conditions.

[0029] Secondly, it achieves active compensation sealing. The hydraulic cylinder-driven pusher plate's pressure compensation component can actively adjust the axial compressive force applied to the sealing ring according to the real-time wear state of the sealing ring. This changes the traditional passive pressure-bearing working mode of the sealing ring, allowing the sealing pressure to be dynamically compensated according to the degree of wear, thus extending the effective service life of the sealing structure.

[0030] Third, it possesses real-time monitoring and remaining life warning capabilities. The sealing ring is made into a capacitor element composed of a conductive layer and an insulating layer. The wear of the sealing ring is calculated in real time through a capacitance detection circuit, and an alarm is triggered when the remaining thickness of the insulating layer is lower than the warning threshold. This allows construction managers to grasp the wear status of the sealing ring in advance, effectively preventing engineering safety accidents such as soil loss and ground settlement caused by sealing failure.

[0031] Fourth, the wear assessment is highly accurate. The assessment algorithm, which combines single-ring independent threshold judgment with multi-ring fusion judgment, can not only respond promptly to the wear exceeding the limit of a single sealing ring, but also comprehensively reflect the overall wear state of the sealing structure, thus improving the accuracy of wear assessment. The overall solution realizes intelligent monitoring and adaptive control of the sealing state, and is suitable for long-distance pipe jacking construction under complex geological conditions. Attached Figure Description

[0032] Figure 1 A schematic diagram of the overall longitudinal section of the sealing and waterproofing structure for the intermediate station during pipe jacking construction. Figure 2 for Figure 1 A magnified schematic diagram of a portion of the central sealing ring area; Figure 3 This is a block diagram illustrating the principle of a seal wear monitoring and active compensation control system. Figure 4 This is a schematic diagram of the cross-section of the sealing ring composite structure; Figure 5 This is a schematic diagram of the wear assessment and determination process; Figure 6 This is a flowchart illustrating the pipe jacking construction method.

[0033] Explanation of reference numerals in the attached drawings: 1—Housing; 2—Front pipe section; 3—Rear pipe section; 4—Annular sealing space; 5—First sealing ring; 6—Second sealing ring; 7—Third sealing ring; 8—Fourth sealing ring; 9—Push plate; 10—Hydraulic cylinder; 11—Conductive layer; 12—Insulating layer; 13—Capacitor detection circuit; 14—Jack; 15—Connecting rod; 16—Piston rod. Detailed Implementation

[0034] The following non-limiting embodiments are intended to enable those skilled in the art to gain a more comprehensive understanding of the present invention, but do not limit the invention in any way. The following content is merely an exemplary description of the scope of protection claimed by the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and such changes should also fall within the scope of protection claimed by the present invention.

[0035] The present invention will be further described below by way of specific embodiments. Unless otherwise specified, all instruments, devices, equipment and other items used in the embodiments of the present invention are obtained through conventional commercial means.

[0036] Example 1 Reference Figure 1 and Figure 2A sealing and waterproofing structure for a relay station in pipe jacking construction includes a shell 1, a front pipe section 2, and a rear pipe section 3. The front pipe section 2 is fixedly connected to the shell 1, and the rear pipe section 3 is inserted into the shell 1, forming an annular sealing space 4 between the shell 1 and the rear pipe section 3. A multi-stage gradient sealing assembly is installed within the annular sealing space 4, comprising a first sealing ring 5, a second sealing ring 6, a third sealing ring 7, and a fourth sealing ring 8, arranged sequentially along the axial direction within the annular sealing space 4. The first sealing ring 5 and the second sealing ring 6 are outer sealing rings with a larger radial dimension, positioned axially close to the open end of the annular sealing space 4; the third sealing ring 7 and the fourth sealing ring 8 are inner sealing rings with a smaller radial dimension, positioned axially close to the closed end of the annular sealing space 4. The radial dimensions of the first sealing ring 5 and the second sealing ring 6 are both larger than the radial dimensions of the third sealing ring 7 and the fourth sealing ring 8, thus forming a gradient waterproofing system with an outer main seal and an inner backup seal. Under normal jacking conditions, the outer first sealing ring 5 and the second sealing ring 6 perform the main sealing function, effectively preventing groundwater and soil particles from entering the pipeline. When the outer sealing ring is worn to a certain extent, the inner third sealing ring 7 and the fourth sealing ring 8 serve as backup sealing layers to take over in time, thereby constructing multiple waterproof barriers and significantly improving the reliability of the sealing structure under long-distance and high-water-pressure conditions.

[0037] Reference Figure 1 and Figure 2 A grease injection hole is provided on the wall of the housing 1 between the first sealing ring 5 and the second sealing ring 6. The grease injection hole is used to inject grease between the first sealing ring 5 and the second sealing ring 6. By injecting grease between the two outer sealing rings, the coefficient of friction between the housing 1 and the sealing rings during the jacking process can be effectively reduced, the friction and wear of the outer sealing rings can be reduced, the wear rate of the outer sealing rings can be slowed down, and the effective service life of the outer sealing rings can be extended.

[0038] Reference Figure 1 , Figure 2The third sealing ring 7 and the fourth sealing ring 8 each have a push plate 9 on their axial side (inner side), and the push plate 9 fits against the end face of the corresponding sealing ring. The hydraulic cylinder 10 is fixed to the inner wall of the rear pipe section 3. The inner wall of the push plate 9 is connected to the piston rod 16 of the hydraulic cylinder 10 through the connecting rod 15, which passes radially through the rear pipe section 3. To accommodate the movement of the push plate 9, the diameter of the through hole for the connecting rod to pass through on the rear pipe section 3 is larger than the diameter of the connecting rod 15, or the through hole is set as a waist-shaped hole, setting the initial position of the connecting rod 15 biased towards the inner side of the sealing ring. The piston rod 16 is arranged axially. When the piston rod 16 extends axially, the push plate 9 moves axially and presses against the corresponding sealing ring, applying axial compressive force to the sealing ring, causing the sealing ring to expand radially under axial compression, thereby increasing the contact pressure between the sealing ring and the outer wall of the rear pipe section 3 and the inner wall of the housing 1, achieving active compensation sealing. The structure of the hydraulic cylinder 10 driving the push plate 9 can precisely control the axial compressive force applied to the sealing ring, changing the traditional passive pressure-bearing working mode of the sealing ring and extending the effective service life of the sealing structure.

[0039] Reference Figure 3 and Figure 4 The first sealing ring 5, the second sealing ring 6, the third sealing ring 7, and the fourth sealing ring 8 are all composed of a conductive layer 11 and an insulating layer 12. The conductive layer 11 and the insulating layer 12 are coaxially arranged, and the sealing ring itself forms a capacitor element. The conductive layer 11 is located on the radially outer side of the sealing ring, and the insulating layer 12 is located on the radially inner side of the conductive layer 11. A capacitance detection circuit 13 is provided inside the rear pipe section 3. The capacitance detection circuit 13 is electrically connected to the conductive layer 11 of each sealing ring through wires to collect the capacitance value of each sealing ring in real time. When the sealing ring wears due to friction during the jacking process, the thickness of the radially outer conductive layer 11 and the insulating layer 12 gradually decreases, resulting in a decrease in the distance between the two plates and an increase in the capacitance value. The capacitance detection circuit 13 calculates the wear amount of each sealing ring in real time based on the change in capacitance value. No external sensors are required, resulting in high structural integration and reliable detection accuracy. The conductive layer 11 is located on the radially outer side, allowing it to preferentially contact the friction medium. The wear direction corresponds to the capacitance change direction, ensuring the accuracy of the wear amount calculation.

[0040] The conductive layer 11 and the insulating layer 12 form a structure similar to a cylindrical capacitor, with a capacitance value of:

[0041] Where C represents the monitored capacitance value; This represents the dielectric constant of the insulating layer, which is determined by the material. Indicates the effective axial width of the sealing ring; This indicates the outer radius of the outer conductive layer 11. This indicates the inner radius of the inner insulating layer 12.

[0042] As construction progressed, the conductive layer 11 was worn away, leading to... The capacitance decreases, and consequently the detected capacitance value changes.

[0043] To ensure that the conductive layer 11 does not come into contact with the rear pipe section 3, the thickness of the conductive layer 11 is relatively small, for example, it can be 0.3 to 0.4 times the radial thickness of the sealing ring, so that even if the conductive layer 11 is installed normally, it will not come into contact with the rear pipe section 3.

[0044] The capacitance detection circuit 13 monitors capacitance using existing technology, such as a chip. One pin of the chip is connected to a conductive layer, and the other pin is connected to the inner wall of the rear tube section 3. The chip is powered by 5V DC and is also connected to a standard resistor. The chip monitors the capacitance value and transmits it to an external control unit. (Except for...) Figure 3 In addition to the schematic diagram shown, other existing detection circuits can also be used for detection.

[0045] Before construction, a relationship model was established between the capacitance value C and the wear amount. This involved using sealing rings of different radial thicknesses, which were then fitted into the sealing grooves of the rear pipe section with the same thickness as the one actually used in construction. The capacitance value was measured using a capacitance detection circuit 13, and the wear amount was converted from the different thicknesses compared to unused sealing rings into a data sample. , i represents the number of samples; the collected capacitance values Using data samples and capacitance value Construct a model relating wear and capacitance. Specific models can include linear, exponential, and logarithmic models.

[0046] During actual construction, the capacitance value is monitored and converted into wear in real time through a relational model, thereby enabling the monitoring of changes in wear.

[0047] The control unit is electrically connected to the capacitor detection circuit 13 and the hydraulic cylinder 10. The control unit receives the wear data of each sealing ring output by the capacitor detection circuit 13 in real time, performs wear assessment and judgment based on the wear amount, and outputs drive commands to the corresponding hydraulic cylinder 10 according to the judgment result, controlling the hydraulic cylinder 10 to drive the push plate 9 to apply extrusion force to the corresponding sealing ring, thereby forming a closed-loop control system for real-time monitoring and active compensation of sealing status.

[0048] Example 2 This embodiment, based on Embodiment 1, expands the configuration of the push plate 9 and hydraulic cylinder 10 to include all four sealing rings. Each of the first sealing ring 5, second sealing ring 6, third sealing ring 7, and fourth sealing ring 8 is correspondingly provided with a push plate 9 and a hydraulic cylinder 10. The four hydraulic cylinders 10 are fixed to corresponding positions on the inner wall of the rear pipe section 3, and each piston rod 16 is fixedly connected to its corresponding push plate 9. The four hydraulic cylinders 10 are independently electrically connected to the control unit. The control unit independently controls the action of the corresponding hydraulic cylinder 10 according to the real-time wear of each sealing ring, achieving precise independent compensation control for each sealing ring and adapting to the differentiated compensation needs of different sealing rings at different wear stages.

[0049] The control unit is electrically connected to the proportional control valves of each hydraulic cylinder 10. The proportional control valves continuously adjust the hydraulic pressure of the corresponding hydraulic cylinder 10 according to the control signal output by the control unit. The control unit outputs control signals to the corresponding proportional control valves based on the real-time wear of each sealing ring. The greater the wear, the stronger the control signal output by the control unit, the higher the hydraulic pressure adjusted by the proportional control valve, and the greater the axial compressive force applied to the sealing ring by the push plate 9 driven by the hydraulic cylinder 10. Continuous adjustment of the hydraulic pressure is achieved through the proportional control valves, allowing the compressive force applied to the sealing ring by the push plate 9 to dynamically adapt to the wear, realizing adaptive compensation control and effectively extending the effective sealing life of each sealing ring.

[0050] Example 3 Reference Figure 5 This embodiment focuses on disclosing the specific implementation logic of the wear assessment algorithm executed by the control unit in Embodiment 1. The wear assessment includes two methods: single-cycle independent threshold determination and multi-cycle fusion determination. The two methods are executed synchronously and complement each other.

[0051] In the single-ring independent threshold determination, the control unit pre-sets corresponding single-ring wear thresholds for the first sealing ring 5 and the second sealing ring 6. During the jacking process, the control unit compares the real-time wear amount of each sealing ring with the corresponding single-ring wear threshold. When the wear amount of one of the sealing rings exceeds the corresponding single-ring wear threshold, the control unit sends a command to start the hydraulic cylinder 10 corresponding to the third sealing ring 7. The hydraulic cylinder 10 drives the corresponding push plate 9 to apply axial compressive force to the sealing ring.

[0052] When the wear of both the first sealing ring 5 and the second sealing ring 6 exceeds the corresponding single-ring wear threshold, the control unit sends a command to activate the hydraulic cylinder 10 corresponding to the third sealing ring 7 and the fourth sealing ring 8. Normally, the wear of the two sealing rings is asynchronous. Therefore, when the wear of one of the first sealing ring 5 and the second sealing ring 6 exceeds the single-ring wear threshold, the control unit sends a command to activate the hydraulic cylinder 10 corresponding to the third sealing ring 7. As wear intensifies, when the wear of the other sealing ring exceeds the single-ring wear threshold, the control unit sends a command to activate the hydraulic cylinder 10 corresponding to the fourth sealing ring 8. The hydraulic cylinder 10 drives the corresponding push plate 9 to apply axial compressive force to the sealing ring, promptly compensating for the more severely worn sealing ring and preventing sealing failure due to excessive wear.

[0053] The single-ring wear threshold for the first sealing ring 5 and the second sealing ring 6 is set at 18%-20% of the radial thickness of the corresponding sealing ring. For sealing rings used in intermediate sections of the jacking pipe, they are usually scrapped when the wear reaches 30% of the radial thickness. Therefore, the single-ring wear threshold is used for sealing compensation when the scrapping standard has not yet been reached and the wear is relatively large. The single-ring wear threshold for the outer first sealing ring 5 is the same as that for the second sealing ring 6.

[0054] After the hydraulic cylinders corresponding to the third sealing ring 7 and the fourth sealing ring 8 are both started, the extension of the piston rod of the hydraulic cylinder is adjusted by a multi-ring fusion judgment method.

[0055] In the multi-ring fusion determination, the control unit performs a weighted summation of the wear data of the first sealing ring 5, the second sealing ring 6, the third sealing ring 7, and the fourth sealing ring 8 to obtain a fusion value. The weighting coefficients for the outer sealing rings (i.e., the first and second sealing rings) are higher than those for the inner sealing rings (i.e., the third and fourth sealing rings). Specifically, the wear data fusion calculation is performed using the following formula:

[0056] in, This represents the wear amount of the i-th sealing ring. This represents the wear and tear after weighted fusion. This represents the weighting coefficient of the i-th sealing ring. The weighting coefficients for the first sealing ring 5 and the second sealing ring 6 are between 0.3 and 0.4; the weighting coefficients for the third sealing ring 7 and the fourth sealing ring 8 are between 0.1 and 0.2; and the sum of the weighting coefficients for the first sealing ring 5, the second sealing ring 6, the third sealing ring 7, and the fourth sealing ring 8 is 1.

[0057] The outer sealing ring directly bears the pressure and friction of groundwater, and its wear state has a more significant impact on the overall sealing performance. Assigning a higher weighting coefficient is consistent with the design logic of prioritizing the protection of the outer sealing ring, and improves the rationality of the fusion judgment result.

[0058] When the fusion value exceeds the preset fusion threshold, the control unit outputs a drive command to all hydraulic cylinders 10 to increase the thrust. Each hydraulic cylinder 10 drives the corresponding push plate 9 to further apply axial compressive force to the corresponding sealing ring, triggering the overall compensation strategy and comprehensively improving the overall sealing performance of the sealing structure. Single-ring independent threshold determination can promptly trigger compensation action for a single sealing ring with severe wear, while multi-ring fusion determination comprehensively reflects the overall wear state of the sealing structure. The combination of the two determination methods effectively improves the accuracy and reliability of wear assessment.

[0059] The fusion threshold is set as the scrap condition for a single sealing ring, which is 30% of the radial thickness of the sealing ring.

[0060] Example 4 Reference Figure 6 This embodiment discloses a pipe jacking construction method, which is applied to the construction of a relay room with a sealed and waterproof structure as described in Embodiment 3. The method includes the steps of setting up a main jacking jack in the working well, setting up a relay room in the pipeline, and alternately jacking up the front and rear sections of the pipeline. Specifically, it also includes the following steps.

[0061] Step 1: Install the relay room. Install the relay room in the predetermined position in the pipeline, and confirm that the shell 1, front pipe section 2, rear pipe section 3, first sealing ring 5, second sealing ring 6, third sealing ring 7, fourth sealing ring 8, push plate 9, hydraulic cylinder 10, capacitor detection circuit 13 and control unit are all installed in place, all electrical connection lines are normal, all hydraulic pipeline connections are reliable, and the overall sealing condition of the relay room is good.

[0062] Step Two: Real-time monitoring of seal wear during jacking. During the jacking process, the capacitance detection circuit 13 continuously collects the capacitance values ​​of the first sealing ring 5, the second sealing ring 6, the third sealing ring 7, and the fourth sealing ring 8, and converts the changes in capacitance values ​​into the wear amount of each sealing ring in real time, transmitting the wear data to the control unit. The control unit records the wear trend of each sealing ring in real time, providing a data basis for subsequent judgment and compensation.

[0063] Step 3: Perform single-ring independent threshold determination and trigger corresponding compensation action. The control unit compares the real-time wear of the first sealing ring 5 and the second sealing ring 6 with the corresponding single-ring wear threshold. When the wear of either sealing ring exceeds the corresponding single-ring wear threshold, the control unit outputs a drive command to the hydraulic cylinder 10 corresponding to that sealing ring. The hydraulic cylinder 10 drives the corresponding push plate 9 to apply axial compressive force to the sealing ring, thereby achieving active compensation sealing of the sealing ring.

[0064] Step 4: After the hydraulic cylinders corresponding to the third sealing ring 7 and the fourth sealing ring 8 are both activated, a multi-ring fusion judgment is executed, triggering the overall compensation strategy. The control unit synchronously performs a weighted summation of the wear data of each sealing ring, with the weighting coefficient of the outer sealing ring being higher than that of the inner sealing ring, to obtain the fusion value. When the fusion value exceeds the preset fusion threshold, the control unit outputs a drive command to all hydraulic cylinders 10, and each hydraulic cylinder 10 drives the corresponding push plate 9 to apply axial extrusion force to the corresponding sealing ring, triggering the overall compensation strategy and comprehensively improving the overall sealing performance of the sealing structure. Through the construction control method combining single-ring threshold judgment and multi-ring fusion judgment, intelligent monitoring and adaptive control of the sealing status during pipe jacking construction are achieved.

[0065] Step 5: Respond to the remaining life warning and arrange a maintenance plan. When the capacitance detection circuit 13 detects that the remaining thickness of the conductive layer 11 of any sealing ring is lower than the preset warning threshold, it sends a remaining life warning signal to the control unit, which triggers the alarm device to issue an alarm. Based on the warning information, construction management personnel can understand the wear status of each sealing ring and the expected replacement time, formulate a maintenance plan in advance, and arrange sealing ring replacement work during appropriate construction intervals to effectively prevent engineering safety accidents such as groundwater leakage, soil erosion, and ground subsidence caused by sealing failure.

[0066] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, and is not intended to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of the present invention do not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A sealed and waterproof structure for a relay station in pipe jacking construction, comprising a shell, a front pipe section, and a rear pipe section, wherein the front pipe section is fixedly connected to the shell, the rear pipe section is inserted into the shell, and an annular sealed space is formed between the shell and the rear pipe section, characterized in that, The annular sealing space is provided with a multi-stage gradient sealing assembly, which includes at least two sealing rings, each including an outer sealing ring and an inner sealing ring. The radial dimension of the outer sealing ring is larger than that of the inner sealing ring. The outer sealing ring is axially close to the open end of the annular sealing space, and the inner sealing ring is axially close to the closed end of the annular sealing space. At least a portion of the sealing ring has a push compensation assembly on its axial side surface. The push compensation assembly includes a push member and a drive mechanism. The drive mechanism is pulsatorically connected to the push member. The push member abuts against the axial end face of the sealing ring. The sealed and waterproof structure is also connected to a wear monitoring component, which is used to detect the amount of wear on the sealing ring. The wear monitoring component is connected to a control unit, which is electrically connected to the wear monitoring component and the drive mechanism, and is used to perform wear assessment and control the operation of the drive mechanism based on the amount of wear.

2. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 1, characterized in that: The multi-stage gradient sealing assembly includes a first sealing ring, a second sealing ring, a third sealing ring, and a fourth sealing ring. The first and second sealing rings are outer sealing rings, and the third and fourth sealing rings are inner sealing rings. The radial dimensions of the first and second sealing rings are both larger than the radial dimensions of the third and fourth sealing rings. The first, second, third, and fourth sealing rings are arranged sequentially along the axial direction within the annular sealing space.

3. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 2, characterized in that: A grease injection hole is provided on the housing wall between the first sealing ring and the second sealing ring, and the grease injection hole is used to inject lubricating grease between the first sealing ring and the second sealing ring.

4. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 2, characterized in that: The driving mechanism is a hydraulic cylinder, the pushing component is a push plate, the push plate is disposed on the axial side of the sealing ring and fits against the end face of the sealing ring, the hydraulic cylinder is fixed on the inner wall of the rear pipe section, the piston rod of the hydraulic cylinder is fixedly connected to the push plate, and when the piston rod extends axially, the push plate presses the corresponding sealing ring axially.

5. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 4, characterized in that: Each of the first and second sealing rings is provided with a push plate and a hydraulic cylinder. The two hydraulic cylinders are independently electrically connected to the control unit. The control unit independently controls the action of the corresponding hydraulic cylinder according to the wear of each sealing ring.

6. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 1, characterized in that: The wear monitoring component is a capacitance detection circuit; The sealing ring is composed of a conductive layer and an insulating layer. The conductive layer and the insulating layer are coaxially arranged, and the sealing ring itself forms a capacitor element. A capacitance detection circuit is provided on the housing. The capacitance detection circuit is electrically connected to the conductive layer and the inner wall of the rear pipe section through wires. It is used to collect the capacitance value of the sealing ring in real time and convert the capacitance value into wear amount.

7. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 6, characterized in that: The conductive layer is located radially outside the sealing ring, and the insulating layer is located radially inside the conductive layer; the capacitance detection circuit calculates the wear amount of the sealing ring based on the capacitance value.

8. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 6, characterized in that: The capacitance detection circuit calculates the wear of the sealing ring in real time. When the wear exceeds the corresponding warning threshold, the capacitance detection circuit sends a remaining life warning signal to the control unit, and the control unit responds to the remaining life warning signal to trigger an alarm.

9. The sealing and waterproof structure of the intermediate station in pipe jacking construction according to claim 1, characterized in that: The wear assessment judgment performed by the control unit includes single-turn independent threshold judgment and multi-turn fusion judgment; In the single-ring independent threshold determination, the control unit compares the wear amount of each sealing ring with the corresponding single-ring wear threshold. When the wear amount of any sealing ring exceeds the corresponding single-ring wear threshold, the control unit outputs a drive command to the drive mechanism corresponding to that sealing ring. In the multi-ring fusion determination, the control unit performs a weighted summation of the wear data of each sealing ring to obtain a fusion value. When the fusion value exceeds a preset fusion threshold, the control unit outputs a drive command to all drive mechanisms.

10. A pipe jacking construction method, applied to the sealing and waterproofing structure of the intermediate pipe jacking construction as described in any one of claims 1-9, characterized in that: Includes the following steps: Step 1: Install the repeater station; Step 2: Monitor the wear of the sealing ring in real time during the jacking process; Step 3: Perform a single-lap independent threshold determination and trigger the corresponding compensation action; Step 4: After the hydraulic cylinders corresponding to the third and fourth sealing rings are both started, perform multi-ring fusion judgment and trigger the overall compensation strategy; Step 5: Respond to remaining life warnings and schedule maintenance.

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