A construction method for trenchless repair of drainage pipes

Abstract

The present invention discloses a method for trenchless repair of drainage pipes, comprising the following steps: step 1: blocking and water regulation; step 2: pipeline desilting and CCTV inspection; step 3: determining grouting materials; step 4: determining grouting range and parameters; step 5: grouting; step 6: cutting and smoothing; step 7: local reinforcement; step 8: pipe interface dislocation stress and material optimization; step 9: stainless steel quick lock installation; step 10: stainless steel quick lock installation; step 11: stainless steel quick lock repair effect inspection. The present invention can select the optimal grouting material according to the specific geological conditions and pipeline conditions, and calculate the grouting range, grouting volume, grouting pressure and other parameters. Then, the drainage pipe pretreatment grouting reinforcement and stainless steel quick lock local lining trenchless repair construction technology are adopted. The consolidation body reinforces the soil body and forms a "double insurance" state with the steel collar, which greatly guarantees the service life of the pipeline.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline repair, and in particular to a construction method for trenchless repair of a drainage pipeline. Background Art

[0002] Trenchless pretreatment technology for drainage pipes is the foundation of trenchless repair. Before trenchless repair, some pipes are severely damaged and cannot be directly repaired without prior treatment. For example, when repairing a collapsed drainage pipe, the soil layer above it often needs to be reinforced to prevent problems such as quicksand. Similarly, when repairing deformed plastic pipes, the deformed portion is often cut to restore it to a rounded shape. However, this cut will thin the original pipe wall, making it prone to rupture and collapse. Pipe pretreatment and reinforcement are also necessary in these situations. Commonly used trenchless local repair techniques include patching, point-based CIPP, and stainless steel double expansion rings.

[0003] Conventional local repair technology of lining patching is not conducive to secondary repair and maintenance for the expansion of pipeline diseases in the later stage. The repair parameters are difficult to quantify accurately. Overlapping repairs can easily affect the normal water flow section. In addition, it requires the demolition of road pavement and road accessories, which is costly and time-consuming. Summary of the Invention

[0004] The present invention provides a construction method for trenchless repair of drainage pipes. The method can select the optimal grouting material according to the specific geological conditions and pipeline conditions, and calculate the grouting range, grouting volume, grouting pressure and other parameters. Then, the drainage pipe pretreatment grouting reinforcement and stainless steel quick-lock local lining trenchless repair construction technology are adopted. The consolidation body reinforces the soil body and forms a "double insurance" state with the steel collar, which greatly guarantees the service life of the pipeline and the safety of the trenchless repair construction. The operation is simple and efficient, reduces the occupation and impact on the road surface, reduces costs, has a small construction area, and is flexible in construction time and high in efficiency.

[0005] In order to solve the above technical problems, the present invention provides a method for trenchless repair of drainage pipes, comprising the following steps:

[0006] Step 1: Plugging and water diversion. After the equipment arrives at the site, the construction section is enclosed and fenced, and then the well is opened for ventilation. The blower is used for forced ventilation, and then an inflatable airbag is used to block water upstream and downstream of the pipeline to be repaired. Two plugs are set on the upstream pipe section and one plug is set on the downstream pipe section. Finally, a brick pipe plug is built upstream and downstream. The water in the upstream inspection well of the pipeline section to be repaired is pumped to the downstream inspection well with a water pump, and the accumulated water in the pipeline section to be repaired is pumped to the downstream inspection well;

[0007] Step 2: Pipeline dredging and CCTV inspection. The dredging and inspection integrated construction equipment is composed of high-definition cameras, dredging nozzles, pressure water injection pipes, connecting bolts, etc., and the dredging and inspection integrated equipment is placed into the required dredging culvert through the inspection well. The night vision function of the lens is turned on. According to the siltation situation in the culvert observed by the high-definition camera, the pressurized water injection switch of the cleaning and suction truck is turned on, and the water injection pressure is controlled and gradually increased to the initial pressure value to carry out dredging and advance. The initial pressure is appropriately increased according to the siltation situation to maximize the dredging effect. The equipment is then towed back and recorded to the entrance position. The dredging and inspection work of this section of the culvert is completed.

[0008] Step 3: Determine the grouting material. Use a polyurethane resin grouting material that can quickly stop water and plug leaks, which is more suitable for complex soft soil layers, and an acrylic resin grouting material that can quickly reinforce the soil.

[0009] Step 4: Determine the grouting scope and parameters. Grouting reinforcement for collapsed pipe sections is mainly to reinforce the soil above the pipe to ensure safety during subsequent cutting and local repair. The soil above the pipe can withstand the soil pressure and additional load after reinforcement. The calculation of each grouting volume of penetration grouting should take into account the porosity of the rock and soil and the filling degree of the slurry. Penetration grouting is to achieve reinforcement by draining the air and water in the pores of the soil particle layer through a certain grouting pressure.

[0010] Step 5: Grouting: First inject water blocking material, then inject soil reinforcement material after no water leakage. After solidification, check the grouting effect. After solidification is completed, proceed to the next step.

[0011] Step 6: Cutting and grinding: Use a milling cutter robot to cut and grind the dislocated parts of the pipe interface back and forth to make the inner surface smooth;

[0012] Step 7: Local reinforcement: Use pneumatic cutting tools to cut and dig out the drainage pipe segments and the solidified soil around the pipes in the grouting area, and use jacks to temporarily support the surrounding uncut parts. After cutting one foot, install prefabricated curved steel plates in the hollowed-out part and fix them to form steel pipe sections with the same inner diameter as the original drainage pipe. The steel pipe sections replace the cut-out original segments.

[0013] Step 8: Pipe interface misalignment stress and material optimization: A two-dimensional model was established to simulate the stress and deformation of the rubber ring on the pipe interface under load. The control variable method was used to study the effects of the pipe interface misalignment spacing, the load on the rubber ring, and the thickness of the rubber ring on the deformation of the rubber ring, and the optimal rubber sealing sleeve thickness was selected;

[0014] Step 9: Stainless steel quick lock installation: pre-install the stainless steel ring and rubber sleeve on the surface, and check whether the locking device can work normally;

[0015] Step 10: Install the stainless steel quick lock. First, place the special airbag with wheels into the quick lock and inflate it until it fits the quick lock. Under CCTV monitoring, use a pipeline robot to transport the airbag carrying the quick lock to the repair site. Slowly inflate the airbag so that the stainless steel quick lock slowly expands and fits tightly against the original pipe wall. After confirming that the stainless steel quick lock is fully expanded, release the pressure of the airbag and retract it.

[0016] Step 11: Inspection of the repair effect of the stainless steel quick lock. Use the CCTV pipeline robot to inspect the appearance of the repaired pipeline. Re-evaluate the flow capacity of the drainage pipeline after the stainless steel quick lock technology repair. Complete the entire construction process after meeting the repair parameters.

[0017] As a preferred embodiment of the above technical solution, in step one, forced ventilation is performed by a blower for at least 30 minutes. After ventilation is completed, a toxic gas detector is used to detect the gas conditions in the inspection well, and work can only be carried out in a safe condition.

[0018] As a preferred embodiment of the above technical solution, the integrated dredging and detection equipment in step 2 is a CCTV pipeline robot, and the high-definition camera is set as a demisting pipeline camera.

[0019] As a preferred embodiment of the above technical solution, in step five, grouting is performed by injecting slurry into the soil around the pipe section using the method of inner-pipe grouting or outer-pipe grouting (inner-pipe grouting is used for pipe diameter ≥ 800 mm, and outer-pipe grouting is used for pipe diameter < 800 mm).

[0020] As a preferred embodiment of the above technical solution, the milling cutter robot in step six includes a grinding head, a grinding disc, a camera, a cooling water tank, a hollow rod and a high-pressure water jet assembly. The grinding head is configured to be hydraulically driven and includes cutting teeth, operating at low speed to provide high torque to enhance the grinding effect. A cooling water tank is provided in the center of the grinding disc for spraying cooling water to the cutting teeth. The camera is used to check the condition of the front pipeline. The interior of the hollow rod is filled with a sealing mixture and a nozzle is provided at one end. The high-pressure water jet assembly is used to remove accumulated grinding dirt.

[0021] As a preferred embodiment of the above technical solution, in step seven, the cutting is performed with an advance of 300 to 600 mm, and the steel pipe section is set as two curved steel plates. The curved steel plates are 300 to 600 mm wide and 1.5 to 2 m long. The curved steel plates are set as stainless steel plates, and fixing mechanisms are provided at the two longitudinal ends to achieve the positioning of the curved steel plates.

[0022] As a preferred embodiment of the above technical solution, the stainless steel quick lock in step nine is configured to be installed in a manner that multiple quick locks can be overlapped. The stainless steel quick lock is set at the repair site and expanded by special tools and then locked and fixed with its own special bolts; the rubber sleeve is closed, and integral sealing bosses are provided on both sides of the outside of the rubber sleeve.

[0023] As a preferred embodiment of the above technical solution, the airbag pressure in step 10 is set to 0.35-0.4 MPa.

[0024] As a preferred embodiment of the above technical solution, the appearance inspection of the repaired pipeline in step 11 should meet the following requirements: the rubber sealing ring is accurately installed, completely covers the defects of the part to be repaired, and fits tightly with the original pipeline without any visible groundwater leakage; CCTV pipeline robot inspection shows that the inner wall of the repaired pipeline is smooth, and the rubber sealing ring fits well with the pipeline without any leakage.

[0025] The present invention provides a method for trenchless repair of drainage pipes. By establishing a numerical model of grouting in complex soft soil layers, the optimal grouting material is selected according to the unique geological conditions and pipeline conditions, and the grouting range, grouting volume, grouting pressure and other parameters are calculated. The grouting material is injected into the outer wall of the pipe to be repaired by grouting inside the pipe or grouting outside the pipe according to different pipe diameters. At the same time, the inner lining such as steel sleeve is used for synchronous support in the pipe to ensure the overall structural integrity of the pipe to be repaired, providing safety for subsequent pipe network repairs, and repairing through stainless steel quick locks. The new local repair technology developed on the basis of stainless steel double expansion rings consists of three parts: high-quality stainless steel sleeves, special locking mechanisms and rubber rings. During construction, with the assistance of a pipeline robot, the repair airbag carrying the quick lock is positioned at the part to be repaired, and then inflated and the quick lock is locked. The airbag is expanded and pressed against the repaired part of the pipeline, and then the pressure is released to disengage the airbag to complete the repair. The present invention consolidates the soil through grouting. The consolidated body reinforces the soil and forms a "double insurance" state with the steel ring, which greatly guarantees the service life of the pipeline and the safety of trenchless repair construction. An integrated dredging and detection equipment is formed, and the detection work is carried out simultaneously after the dredging is completed, which greatly improves the efficiency and accuracy of dredging and detection construction. The stainless steel quick lock can be used for local repair of drainage pipes of any material and water supply pipes of a certain pressure. The repair process does not require water interruption, and the operation is simple and efficient. If the defect is large along the axial length of the pipeline, several quick locks can be continuously overlapped and installed, which can be extended indefinitely in theory. The trenchless technology is used to avoid the destruction of urban road pavement and road accessories. The construction area is small, the construction time is flexible, and the impact on traffic is reduced.

[0026] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is the overall flow chart of the present invention;

[0028] Figure 2 This is a schematic diagram of water plugging and water regulation according to the present invention;

[0029] Figure 3 This is a comparison diagram of the consolidation of the grouting material of the present invention;

[0030] Figure 4 This is a schematic diagram of pipeline deformation and collapse according to the present invention;

[0031] Figure 5 Schematic diagram of the relationship between grouting pressure and grouting amount of the present invention;

[0032] Figure 6 This is a schematic diagram of the pipe segment grouting of the present invention;

[0033] Figure 7 Schematic diagram of the cutting and grinding process of the milling cutter robot of the present invention;

[0034] Figure 8 This is a rendering of the polished surface of the present invention;

[0035] Figure 9 This is a schematic diagram of a reinforced pipeline according to the present invention;

[0036] Figure 10 This is a schematic diagram of the deformation of the rubber ring of the pipe interface of the present invention when it is misaligned by 8mm;

[0037] Figure 11 This is a schematic diagram of the deformation of the rubber ring when the pipe interface is misaligned by 10 mm according to the present invention;

[0038] Figure 12 This is a schematic diagram of the deformation of the rubber ring of the pipe interface of the present invention when it is misaligned by 12mm;

[0039] Figure 13 This is a schematic diagram of the deformation of the rubber ring of the pipe interface of the present invention when it is misaligned by 14mm;

[0040] Figure 14 This is a schematic diagram of the deformation of the rubber ring of the pipe interface of the present invention when it is misaligned by 16mm;

[0041] Figure 15 This is a schematic diagram of the deformation of the rubber ring of the pipe interface of the present invention when it is misaligned by 18mm;

[0042] Figure 16 This is a schematic diagram of the deformation of the rubber ring when the pipe interface is misaligned by 20 mm according to the present invention;

[0043] Figure 17 This is a statistical diagram of pipeline interface misalignment and rubber maximum deformation according to the present invention;

[0044] Figure 18 Schematic diagram of the deformation of the rubber ring of the present invention when the internal pressure of the pipeline is 0.1 MPa;

[0045] Figure 19 Schematic diagram of the deformation of the rubber ring of the present invention when the internal pressure of the pipeline is 0.2 MPa;

[0046] Figure 20 Schematic diagram of the deformation of the rubber ring of the present invention when the internal pressure of the pipeline is 0.3 MPa;

[0047] Figure 21 Schematic diagram of deformation of the rubber ring of the present invention when the internal pressure of the pipeline is 0.4 MPa;

[0048] Figure 22 This is a statistical diagram of the internal pressure of the pipeline and the maximum deformation of the rubber ring of the present invention;

[0049] Figure 23 This is a schematic diagram of the deformation of a rubber ring with a thickness of 4 mm according to the present invention;

[0050] Figure 24 This is a schematic diagram of the deformation of a rubber ring with a thickness of 5 mm according to the present invention;

[0051] Figure 25 This is a schematic diagram of the deformation of a rubber ring with a thickness of 6 mm according to the present invention;

[0052] Figure 26 This is a schematic diagram of the deformation of a rubber ring with a thickness of 7 mm according to the present invention;

[0053] Figure 27 This is a schematic diagram of the deformation of a rubber ring with a thickness of 8 mm according to the present invention;

[0054] Figure 28 This is a schematic diagram of positioning the airbag with a quick lock of the present invention;

[0055] Figure 29 It is a schematic diagram of the inflation of the airbag of the present invention.

[0056] In the figure: 1 is the original pipeline, 2 is the grouting pipe, 3 is the solidified rock and soil, 4 is the milling cutter robot, and 5 is the pipeline after grinding. DETAILED DESCRIPTION

[0057] In order to make the purposes, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0058] Example 1:

[0059] See also Figure 1-2The embodiment of the present invention provides a method for trenchless repair of a drainage pipe, comprising the following steps:

[0060] Step 1: Plugging and water diversion. After the equipment arrives at the site, the construction section is enclosed and fenced, and then the well is opened for ventilation. The blower is used for forced ventilation, and then an inflatable airbag is used to block water upstream and downstream of the pipeline to be repaired. Two plugs are set on the upstream pipe section and one plug is set on the downstream pipe section. Finally, a brick pipe plug is built upstream and downstream. The water in the upstream inspection well of the pipeline section to be repaired is pumped to the downstream inspection well with a water pump, and the accumulated water in the pipeline section to be repaired is pumped to the downstream inspection well;

[0061] Step 2: Pipeline dredging and CCTV inspection. The dredging and inspection integrated construction equipment is composed of high-definition cameras, dredging nozzles, pressure water injection pipes, connecting bolts, etc., and the dredging and inspection integrated equipment is placed into the required dredging culvert through the inspection well. The night vision function of the lens is turned on. According to the siltation situation in the culvert observed by the high-definition camera, the pressurized water injection switch of the cleaning and suction truck is turned on, and the water injection pressure is controlled and gradually increased to the initial pressure value to carry out dredging and advance. The initial pressure is appropriately increased according to the siltation situation to maximize the dredging effect. The equipment is then towed back and recorded to the entrance position. The dredging and inspection work of this section of the culvert is completed.

[0062] Step 3: Determine the grouting material. Use a polyurethane resin grouting material that can quickly stop water and plug leaks, which is more suitable for complex soft soil layers, and an acrylic resin grouting material that can quickly reinforce the soil.

[0063] Step 4: Determine the grouting scope and parameters. Grouting reinforcement for collapsed pipe sections is mainly to reinforce the soil above the pipe to ensure safety during subsequent cutting and local repair. The soil above the pipe can withstand the soil pressure and additional load after reinforcement. The calculation of each grouting volume of penetration grouting should take into account the porosity of the rock and soil and the filling degree of the slurry. Penetration grouting is to achieve reinforcement by draining the air and water in the pores of the soil particle layer through a certain grouting pressure.

[0064] Step 5: Grouting: First inject water blocking material, then inject soil reinforcement material after no water leakage. After solidification, check the grouting effect. After solidification is completed, proceed to the next step.

[0065] Step 6: Cutting and grinding: Use a milling cutter robot to cut and grind the dislocated parts of the pipe interface back and forth to make the inner surface smooth;

[0066] Step 7: Local reinforcement: Use pneumatic cutting tools to cut and dig out the drainage pipe segments and the solidified soil around the pipes in the grouting area, and use jacks to temporarily support the surrounding uncut parts. After cutting one foot, install prefabricated curved steel plates in the hollowed-out part and fix them to form steel pipe sections with the same inner diameter as the original drainage pipe. The steel pipe sections replace the cut-out original segments.

[0067] Step 8: Pipe interface misalignment stress and material optimization: A two-dimensional model was established to simulate the stress and deformation of the rubber ring on the pipe interface under load. The control variable method was used to study the effects of the pipe interface misalignment spacing, the load on the rubber ring, and the thickness of the rubber ring on the deformation of the rubber ring, and the optimal rubber sealing sleeve thickness was selected;

[0068] Step 9: Stainless steel quick lock installation: pre-install the stainless steel ring and rubber sleeve on the surface, and check whether the locking device can work normally;

[0069] Step 10: Install the stainless steel quick lock. First, place the special airbag with wheels into the quick lock and inflate it until it fits the quick lock. Under CCTV monitoring, use a pipeline robot to transport the airbag carrying the quick lock to the repair site. Slowly inflate the airbag so that the stainless steel quick lock slowly expands and fits tightly against the original pipe wall. After confirming that the stainless steel quick lock is fully expanded, release the pressure of the airbag and retract it.

[0070] Step 11: Inspection of the repair effect of the stainless steel quick lock. Use the CCTV pipeline robot to inspect the appearance of the repaired pipeline. Re-evaluate the flow capacity of the drainage pipeline after the stainless steel quick lock technology repair. Complete the entire construction process after meeting the repair parameters.

[0071] This technical solution is applicable to the pretreatment and repair projects of municipal drainage pipelines with various pipes of diameters DN300 to DN2600 that have local collapse and serious tangles.

[0072] The present embodiment provides a method for the construction of trenchless repair of drainage pipes. By establishing a numerical model of grouting in complex soft soil layers, the optimal grouting material is selected according to the unique geological conditions and pipeline conditions, and the grouting range, grouting volume, grouting pressure and other parameters are calculated. The grouting material is injected into the outer wall of the pipe to be repaired by grouting inside the pipe or grouting outside the pipe according to different pipe diameters. At the same time, the inner lining such as steel sleeve is used for synchronous support inside the pipe to ensure the overall structural integrity of the pipe to be repaired, providing safety for subsequent pipe network repairs, and repairing by stainless steel quick lock, a new type of local repair technology developed on the basis of stainless steel double expansion ring, which consists of three parts: high-quality stainless steel sleeve, special locking mechanism and rubber ring. During construction, with the assistance of the pipeline robot, the repair airbag carrying the quick lock is positioned to the part to be repaired, and then inflated to support the quick lock. The invention opens and sticks to the repaired part of the pipeline, then releases the pressure to release the airbag, and the repair is completed. The invention consolidates the soil through grouting, and the consolidated body reinforces the soil and forms a "double insurance" state with the steel ring, which greatly guarantees the service life of the pipeline and the safety of trenchless repair construction. It forms an integrated dredging and detection equipment, and performs detection work simultaneously after the dredging is completed, which greatly improves the efficiency and accuracy of dredging and detection construction. The stainless steel quick lock can be used for local repair of drainage pipes of any material and water supply pipes of a certain pressure. The repair process does not require water interruption, and the operation is simple and efficient. If the defect is large along the axial length of the pipeline, several quick locks can be continuously overlapped and installed, which can be extended indefinitely in theory. The trenchless technology is used to avoid the destruction of urban road pavement and road accessories, the construction area is small, the construction time is flexible, and the impact on traffic is reduced.

[0073] In a further feasible embodiment of this embodiment, in step one, the blower is used for forced ventilation, and the ventilation time is at least 30 minutes. After the ventilation is completed, a toxic gas detector is used to detect the gas situation in the inspection well, and the well operation can only be carried out when it is safe.

[0074] The forced ventilation by the blower in this embodiment ensures that construction can be carried out underground and avoids accidents caused by gas inhalation by personnel.

[0075] In a further feasible embodiment of this embodiment, the integrated dredging and detection equipment in step 2 is a CCTV pipeline robot, and the high-definition camera is configured as a demisting pipeline camera.

[0076] The integrated dredging and detection equipment in this embodiment performs detection work simultaneously after dredging is completed, which greatly improves the efficiency and accuracy of dredging and detection construction, and realizes visual and precise dredging. The detection work is performed simultaneously after dredging is completed, which greatly improves the efficiency and accuracy of dredging and detection construction. The demisting pipeline camera is used to avoid different levels of fog in the pipeline due to seasonal influences, so as to reduce the impact of fog on the equipment detection effect.

[0077] In a further possible implementation of this embodiment, in step five, grouting is performed by injecting slurry into the soil around the pipe segment using the method of inner-pipe grouting or outer-pipe grouting (inner-pipe grouting is used for pipe diameters ≥ 800 mm, and outer-pipe grouting is used for pipe diameters < 800 mm).

[0078] In the grouting process of this embodiment, refer to the attached Figure 3 Since the environment of this project is rich in groundwater and has serious leakage, water-blocking materials are injected first. After there is no leakage, soil reinforcement materials are injected. The grouting effect is tested after solidification. The water-blocking slurry reacts and expands rapidly when it comes into contact with water (within about 1 to 5 seconds), thereby playing a role in blocking water and preventing leakage. The soil reinforcement slurry is a polyurethane chemical grouting material with a solidification time of 18 to 24 hours, which can quickly solidify the loose soil layer to form a solid whole.

[0079] In a further feasible embodiment of this embodiment, the milling cutter robot in step six includes a grinding head, a grinding disc, a camera, a cooling water tank, a hollow rod and a high-pressure water jet assembly, the grinding head is configured to be hydraulically driven and includes cutting teeth, and operates at low speed to provide high torque to enhance the grinding effect, a cooling water tank is provided in the center of the grinding disc for spraying cooling water to the cutting teeth, the camera is used to check the condition of the front pipeline, the interior of the hollow rod is filled with a sealing mixture and a nozzle is provided at one end, and the high-pressure water jet assembly is used to remove accumulated grinding dirt.

[0080] The milling robot's grinding head in this embodiment can be equipped with various shapes of diamonds, carbide, and the like to accommodate different materials, such as clay, concrete, polymers, and steel. Some more powerful milling robots can cut through reinforced steel. The cutting teeth are typically cooled by spraying water from the center of the grinding disc. The axle is typically driven by a motor, such as the rotation and extension of the grinding head. CCTV on the grinding head monitors the robot's operation, and a remote camera can be added to monitor the condition of the pipeline ahead. Some grinding robots can spray sealing compound through a hollow rod to prevent leakage caused by mortar being affected by certain factors when filling the robot. High-pressure water jets can also be installed on the robot to remove accumulated grinding debris.

[0081] In a further feasible embodiment of this embodiment, the cutting in step seven is carried out with an advance of 300 to 600 mm, the steel pipe section is set as two curved steel plates, the curved steel plates are 300 to 600 mm wide and 1.5 to 2 m long, the curved steel plates are set as stainless steel plates, and fixing mechanisms are provided at the two longitudinal ends to achieve the positioning of the curved steel plates.

[0082] In the local reinforcement of this embodiment, the reinforcement of the soil by the consolidation body and the steel collar form a "double insurance" state, which greatly ensures the service life of the pipeline and the safety of the trenchless repair construction.

[0083] In a further feasible embodiment of this embodiment, the stainless steel quick lock in step nine is configured to be installed in a manner that multiple quick locks can be overlapped. The stainless steel quick lock is set at the repair site and expanded by special tools and then locked and fixed with its own special bolts; the rubber sleeve is closed, and integral sealing bosses are provided on both sides of the outside of the rubber sleeve.

[0084] The stainless steel quick lock in this embodiment should be able to cover the defect to be repaired, and should be at least 100mm longer than the depression to be repaired from front to back; when the axial length of the defect exceeds the length of a single quick lock, multiple quick locks can be installed in an overlapping manner. During installation, the rear quick lock should press the rubber sleeve that protrudes from the front quick lock to ensure sealing. The stainless steel collar of DN600mm and below is processed and formed from a whole piece of steel plate; the stainless steel collar above DN600mm is assembled from 2 to 3 pieces of special stainless steel ring pieces, which are expanded at the repair site with special tools and then locked and fixed with special bolts.

[0085] In a further feasible embodiment of this embodiment, the airbag pressure in step 10 is set to 0.35-0.4 MPa.

[0086] The air bag in this embodiment is ensured to move together with the stainless steel quick lock and to slowly expand the quick lock after expansion and to cling to the original inner wall of the pipe.

[0087] In a further feasible embodiment of this embodiment, the appearance inspection of the repaired pipeline in step 11 should meet the following requirements: the rubber sealing ring is accurately installed, completely covers the defects of the part to be repaired, and fits tightly with the original pipeline without any visible groundwater leakage; the CCTV pipeline robot inspection shows that the inner wall of the repaired pipeline is smooth, and the rubber sealing ring fits well with the pipeline without any leakage.

[0088] The CCTV pipeline robot in this embodiment inspects the appearance of the repaired pipeline. According to the "Technical Code for Trenchless Repair and Renewal of Urban Water Supply Pipelines" CJJ / T 244-2016, the appearance inspection of the repaired pipeline should meet the following requirements: the rubber sealing ring is accurately installed in the position, completely covers the defects of the repaired area, and fits tightly with the original pipeline without any visible groundwater leakage. CCTV inspection shows that the inner wall of the repaired pipeline is smooth, the rubber sealing ring fits well with the pipeline, and there is no leakage. The camera installed on the CCTV pipeline robot should also be a defogging camera.

[0089] Example 2:

[0090] Based on the first embodiment, refer to the attached Figure 4 and Figure 5During the grouting process, the grouting reinforcement of the collapsed pipe section is mainly to strengthen the soil above the pipe to ensure the safety during subsequent cutting and local repair. The soil above the pipe needs to be reinforced to be able to withstand the soil pressure and additional loads above. The thick-walled cylinder model in elastic-plastic physics is used for deduction:

[0091] Assuming that the inner and outer walls are subjected to uniformly distributed pressures qa and qb, and ignoring gravity, the stress components of the cylinder are:

[0092]

[0093] τ γθ =0(5.2.4-3)

[0094] Where: r0--the inner diameter of the cylinder (mm);

[0095] R--outer diameter of the cylinder (mm);

[0096] q a --Force on the inner wall of the tube;

[0097] q b --The outer wall of the pipe is subjected to stress.

[0098] When studying the scope of pipeline pretreatment grouting reinforcement, since the inner wall of the pipeline does not bear internal pressure, when r = r0, let qa = 0, the stress state of the inner wall of the pipeline is a unidirectional stress state, then the stress component is simplified to:

[0099] σ γ =0(5.2.4-4)

[0100]

[0101] τ γθ =0(5.2.4-6)

[0102] Assuming the compressive strength of the soil after grouting reinforcement is σc, then:

[0103]

[0104] Assume the distance from the ground to the center of the pipeline is H:

[0105]

[0106] Resolved into:

[0107]

[0108] Solving this equation will give R, and then the grouting reinforcement thickness T can be solved:

[0109] T=R-r0(5.2.4-10)

[0110] That is, the grouting reinforcement thickness is the difference between the slurry diffusion radius and the outer wall of the pipe.

[0111] The calculation of each grouting volume of penetration grouting should take into account the porosity of the rock and soil, the filling degree of the slurry, etc. The quality of penetration grouting depends on the filling degree of the voids within the penetration radius. The higher the filling rate, the better the grouting effect. The commonly used grouting volume calculation formula for penetration grouting is:

[0112] Q=πr 2 hnα(1+β)(5.2.4-11)

[0113] In the formula: r--is the penetration radius;

[0114] h--thickness of penetration grouting;

[0115] n--porosity of soil;

[0116] α--effective perfusion coefficient;

[0117] 1+β--loss coefficient, ranging from 1.1 to 2.0.

[0118] Commonly used strata for permeation grouting include sand layers and gravel layers. The porosity of each stratum is shown in Table 5.2.4-1; the grouting coefficient is shown in Table 5.2.4-2; and the grouting filling rate is shown in Table 5.2.4-3.

[0119] Table 5.2.4-1 Porosity of formation n

[0120]

[0121]

[0122] Table 5.2.4-2 Relationship between grouting coefficient, grout viscosity and soil quality

[0123]

[0124] Table 5.2.4-3 Grouting filling rate of different soil layers

[0125]

[0126] Infiltration grouting is a method of achieving reinforcement by draining away the air and water in the pores of the soil particle layer through a certain grouting pressure. Excessive pressure will cause changes and damage to the ground, foundation, and structure. Therefore, the maximum allowable pressure of infiltration grouting is determined as follows:

[0127] (1) Determine based on the curve

[0128] During the grouting test, the grouting pressure was gradually increased to obtain the curve relationship between pressure and grouting volume as shown in the attached figure of the specification. Figure 5At the pressure point pf, the grouting volume suddenly increases, indicating that the formation has cracked. This point is the maximum allowable grouting pressure.

[0129] (2) According to the empirical formula

[0130] [p e ]=c(0.75T+Kλh) (5.2.4-12) or [p e ]=βγT+CKλh (5.2.4-13)

[0131] Where: [pe]--allowable grouting pressure (kPa);

[0132] H--the depth from the ground to the grouting section (m);

[0133] C - coefficient related to grouting sequence;

[0134] Sequence 1 hole C = 1; Sequence 2 hole C = 1.25; Sequence 3 hole C = 1.5;

[0135] β--coefficient, deformation between 1 and 3;

[0136] T--thickness of foundation cover layer;

[0137] K - coefficient related to grouting method;

[0138] Λ--coefficient related to formation properties.

[0139] (3) Determined based on empirical values:

[0140] The maximum grouting pressure is 1 to 2 times the sum of the soil pressure of the overburden layer and the load pressure of the superstructure.

[0141] Example 3:

[0142] Based on the first embodiment, refer to the attached Figure 6-9 Since the environment of this project is rich in groundwater and has serious leakage, water blocking materials are injected first. After there is no leakage, soil reinforcement materials are injected. After solidification, the grouting effect is tested. For this project, infiltration grouting in the static pressure grouting method is generally selected. In the figure, 1 is the original pipeline, 2 is the grouting pipe, 3 is the solidified rock and soil, 4 is the milling cutter robot, and 5 is the smoothed pipeline.

[0143] During the cutting, grinding and local reinforcement processes, the water-blocking slurry reacts and expands rapidly when it comes into contact with water (within about 1 to 5 seconds), thereby blocking water and preventing leakage. The soil reinforcement slurry is a polyurethane chemical grouting material with a curing time of 18 to 24 hours, which can quickly solidify the loose soil layer to form a solid whole.

[0144] The grouting process uses PUR H100 water-blocking grouting material and PUR H40 soil reinforcement grouting material. H100 is injected first, and after there is no water leakage, H40 is injected and solidified for 24 hours. The grouting pressure is about 0.1-0.3 MPa. The grouting amount is 5 kg / root of H100 grouting material and 10 kg / root of H40 material. After solidification, a pneumatic cutting tool is used to cut a 100×100 window in the grouting area to observe the soil condition, and steel bars are inserted to detect the solidification of the soil layer around the pipe. If the steel bars are difficult to insert, it indicates that the soil is well solidified, and then proceed to the next step.

[0145] The grinding head can be equipped with diamonds, carbides, etc. of various shapes to suit different materials, such as clay, concrete, polymers, steel, etc. Some more powerful milling cutter robots can cut steel reinforced materials. The cooling of the cutting teeth is generally completed by spraying water from the center of the grinding disc. The wheel axle is generally driven by a motor, such as the rotation and extension of the grinding head. The CCTV on the grinding head monitors the robot's operation process. A camera at a farther distance can also be added to check the condition of the pipeline in front. Some grinding robots can spray sealing mixture from a hollow rod to avoid leakage caused by some influence of mortar when filling the robot. High-pressure water jet equipment can also be installed on the robot to remove accumulated grinding dirt. The effect after grinding is shown in the attached figure of the instruction manual. Figure 8 .

[0146] Example 4:

[0147] By establishing a two-dimensional model, the stress deformation of the rubber ring on the pipe interface under the action of load was simulated. The control variable method was adopted to study the influence of the size of the pipe interface misalignment spacing, the size of the load on the rubber ring, and the influence of different rubber ring thickness on the deformation of the rubber ring. The optimal rubber sealing sleeve thickness was selected. In this simulation, the influence of the pipe interface misalignment spacing, the influence of the pipeline internal pressure load, and the influence of the rubber ring thickness were studied respectively. The specific simulation is as follows:

[0148] Study on the influence of misalignment spacing on pipe interface: The cross-section size of the rubber ring is established to be 100mm×4mm. First, the load on the rubber ring is fixed to 0.1MPa, and the right pipe is moved to change the distance between the two rigid bodies to 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, and 20mm respectively. The simulation results are shown in the attached figure of the manual. Figure 10-16 From the above numerical simulation results, the maximum deformation of the rubber ring when the load is 0.1MPa is calculated as the deformation of the two rigid bodies with different distances between them. Figure 17 From the curve graph, it can be concluded that when the applied load is fixed, within a certain range, the deformation of the rubber ring increases with the increase of the distance between the two rigid bodies, and this growth trend continues to increase with the increase of the distance.

[0149] Study on the influence of internal pressure load in pipeline: The distance between the two rigid bodies is fixed at 10mm, and the load size is changed to 0.1MPa, 0.2MPa, 0.3MPa, and 0.4MPa respectively. The simulation results are shown in the attached figure of the manual. Figure 18-21 From the above numerical simulation results, the maximum deformation of the rubber ring with different applied loads when the rigid body spacing is fixed at 10mm is statistically analyzed, as shown in the figure of the specification. Figure 22 From the curve graph, it can be concluded that when the rigid body spacing is fixed, within a certain range, the deformation of the rubber ring increases with the increase of the load applied to the rubber ring surface.

[0150] Influence of rubber ring thickness: Change the cross-sectional thickness of the rubber ring to 4mm, 5mm, 6mm, 7mm, and 8mm, fix the load on the rubber ring to 0.1MPa, and fix the interface offset spacing to 10mm. The simulation results are shown in the attached figure of the manual. Figure 23-27 By changing the thickness of the rubber sealing ring, the deformation law of rubber rings of different thicknesses is analyzed under the action of an external load of 0.1MPa and a pipe interface dislocation of 10mm. It can be seen that when the thickness of the rubber ring increases, the stress it bears is reduced to a certain extent. It is found that the repair effect can be effectively enhanced by changing the thickness of the rubber sealing ring.

[0151] After the above research and comparison of the two-dimensional model, the rubber ring thickness of 6mm was selected when the rigid body spacing of DN300~DN2600 is between 8mm~20mm through economic comparison and stress calculation.

[0152] Embodiment 5:

[0153] Based on the first embodiment, refer to the accompanying drawings. Figures 28-29 After the stainless steel quick lock is installed, the repair airbag carrying the quick lock is positioned at the repair site. The airbag is then inflated to expand the quick lock and place it close to the repaired part of the pipe. In addition, the flow capacity of the drainage pipe repaired with the stainless steel quick lock technology is re-evaluated using the following formula:

[0154]

[0155] Where: B is the ratio of the flow capacity of the CIPP pipe to the original pipe;

[0156] n e ——Roughness coefficient of original pipeline;

[0157] n1——CIPP pipe roughness coefficient;

[0158] D I ——CIPP pipe inner diameter (mm);

[0159] DE ——Original pipe inner diameter (mm).

[0160] For example, if the inner diameter of the original pipeline is 778mm, the inner diameter of the pipeline after the stainless steel quick lock repair is 770mm. The original pipeline is a PE pipe with a roughness coefficient of 0.009 and a rubber sealing ring with a roughness coefficient of 0.01. After substituting the formula, the ratio of the flow capacity of the repaired pipeline to the original pipeline is 113%. The flow capacity of the repaired pipeline increases by 13%, indicating that the stainless steel quick lock repair can improve the flow capacity of the pipeline.

[0161] Example 6:

[0162] Based on the above embodiment, the duration of this technical solution is compared with the stainless steel double expansion ring repair process and the excavation repair process, as follows:

[0163]

[0164] Compared with traditional excavation repair methods, this method reduced traffic diversion for pipeline repair by 564 m, increasing economic benefits by approximately 120,000 yuan. It also reduced the transportation of 564 m of excavated soil and a trench depth of 4 m, totaling 6,768 m³. It also reduced the removal of 564 m of old pipe and the installation of 7,375 m of Larsen sheet piles, increasing economic benefits by approximately 980,000 yuan. It also reduced backfill of crushed stone and medium-coarse sand cushion by a total of 705 m³, the base C15 concrete by 353 m³, and the backfill of sand by 8,112 m³, increasing economic benefits by approximately 1.15 million yuan. It also reduced the purchase of approximately 564 m of DN800 concrete pipe, increasing economic benefits by approximately 130,000 yuan. Therefore, this method shortened the construction period by 48 days compared to traditional excavation repair, saving 2.38 million yuan in construction costs.

[0165] Compared with the stainless steel double expansion ring repair process, it does not require manual downhole operation, greatly improving the quality and efficiency of pipeline repair, shortening the construction period by 9 days, and saving labor costs of approximately 50,000 yuan.

[0166] This technical solution utilizes trenchless technology, avoiding the need to remove urban road pavement and roadside attachments. It minimizes the construction area, allows for flexible construction schedules, and reduces traffic disruptions. Construction eliminates the generation of debris that could impact urban road hygiene and dust. This solution addresses the need for trenchless repairs to address pipeline maintenance requirements. By simulating flow capacity assessment, stress analysis of dislocations, and material optimization, it provides effective guidance for subsequent construction.

[0167] In the description of this specification, reference to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and integrate different embodiments or examples described in this specification, as well as features of different embodiments or examples, unless otherwise inconsistent.

[0168] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0169] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A method for trenchless repair of a drainage pipe, characterized in that: The following steps are involved: Step 1: Plugging and water diversion. After the equipment arrives at the site, the construction section is enclosed and fenced, and then the well is opened for ventilation. The blower is used for forced ventilation, and then an inflatable airbag is used to block water upstream and downstream of the pipeline to be repaired. Two plugs are set on the upstream pipe section and one plug is set on the downstream pipe section. Finally, a brick pipe plug is built upstream and downstream. The water in the upstream inspection well of the pipeline section to be repaired is pumped to the downstream inspection well with a water pump, and the accumulated water in the pipeline section to be repaired is pumped to the downstream inspection well; Step 2: Pipeline dredging and CCTV inspection. The dredging and inspection integrated construction equipment is composed of high-definition cameras, dredging nozzles, pressure water injection pipes, connecting bolts, etc., and the dredging and inspection integrated equipment is placed into the required dredging culvert through the inspection well. The night vision function of the lens is turned on. According to the siltation situation in the culvert observed by the high-definition camera, the pressurized water injection switch of the cleaning and suction truck is turned on, and the water injection pressure is controlled and gradually increased to the initial pressure value to carry out dredging and advance. The initial pressure is appropriately increased according to the siltation situation to maximize the dredging effect. The equipment is then towed back and recorded to the entrance position. The dredging and inspection work of this section of the culvert is completed. Step 3: Determine the grouting material. Use a polyurethane resin grouting material that can quickly stop water and plug leaks, which is more suitable for complex soft soil layers, and an acrylic resin grouting material that can quickly reinforce the soil. Step 4: Determine the grouting scope and parameters. Grouting reinforcement for collapsed pipe sections is mainly to reinforce the soil above the pipe to ensure safety during subsequent cutting and local repair. The soil above the pipe can withstand the soil pressure and additional load after reinforcement. The calculation of each grouting volume of penetration grouting should take into account the porosity of the rock and soil and the filling degree of the slurry. Penetration grouting is to achieve reinforcement by draining the air and water in the pores of the soil particle layer through a certain grouting pressure. Step 5: Grouting: First inject water blocking material, then inject soil reinforcement material after no water leakage. After solidification, check the grouting effect. After solidification is completed, proceed to the next step. Step 6: Cutting and grinding: Use a milling cutter robot to cut and grind the dislocated parts of the pipe interface back and forth to make the inner surface smooth; Step 7: Local reinforcement: Use pneumatic cutting tools to cut and dig out the drainage pipe segments and the solidified soil around the pipes in the grouting area, and use jacks to temporarily support the surrounding uncut parts. After cutting one foot, install prefabricated curved steel plates in the hollowed-out part and fix them to form steel pipe sections with the same inner diameter as the original drainage pipe. The steel pipe sections replace the cut-out original segments. Step 8: Pipe interface misalignment stress and material optimization: A two-dimensional model was established to simulate the stress and deformation of the rubber ring on the pipe interface under load. The control variable method was used to study the effects of the pipe interface misalignment spacing, the load on the rubber ring, and the thickness of the rubber ring on the deformation of the rubber ring, and the optimal rubber sealing sleeve thickness was selected; Step 9: Stainless steel quick lock installation: pre-install the stainless steel ring and rubber sleeve on the surface, and check whether the locking device can work normally; Step 10: Install the stainless steel quick lock. First, place the special airbag with wheels into the quick lock and inflate it until it fits the quick lock. Under CCTV monitoring, use a pipeline robot to transport the airbag carrying the quick lock to the repair site. Slowly inflate the airbag so that the stainless steel quick lock slowly expands and fits tightly against the original pipe wall. After confirming that the stainless steel quick lock is fully expanded, release the pressure of the airbag and retract it. Step 11: Inspection of the repair effect of the stainless steel quick lock. Use the CCTV pipeline robot to inspect the appearance of the repaired pipeline. Re-evaluate the flow capacity of the drainage pipeline after the stainless steel quick lock technology repair. Complete the entire construction process after meeting the repair parameters.

2. A method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step one, the blower is used for forced ventilation, and the ventilation time is at least 30 minutes. After the ventilation is completed, a toxic gas detector is used to check the gas conditions in the inspection well. Only when it is safe can the well be operated.

3. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: The integrated dredging and detection equipment in step 2 is a CCTV pipeline robot, and the high-definition camera is set as a demisting pipeline camera.

4. A method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step five, grouting is performed by injecting slurry into the soil around the pipe section using the method of inner-pipe grouting or outer-pipe grouting (inner-pipe grouting is used for pipe diameters ≥ 800 mm, and outer-pipe grouting is used for pipe diameters < 800 mm).

5. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step six, the milling cutter robot includes a grinding head, a grinding disc, a camera, a cooling water tank, a hollow rod and a high-pressure water jet assembly. The grinding head is configured to be hydraulically driven and includes cutting teeth, operating at low speed to provide high torque to enhance the grinding effect. A cooling water tank is provided in the center of the grinding disc for spraying cooling water to the cutting teeth. The camera is used to check the condition of the front pipeline. The interior of the hollow rod is filled with a sealing compound and a nozzle is provided at one end. The high-pressure water jet assembly is used to remove accumulated grinding dirt.

6. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step seven, the cutting is carried out at an advance of 300 to 600 mm. The steel pipe section is set as two curved steel plates. The curved steel plates are 300 to 600 mm wide and 1.5 to 2 m long. The curved steel plates are set as stainless steel plates. Fixing mechanisms are set at the two longitudinal ends to achieve the positioning of the curved steel plates.

7. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step nine, the stainless steel quick lock is set to be installed in a way that multiple quick locks can be overlapped. The stainless steel quick lock is set at the repair site and expanded by special tools and then locked and fixed with its own special bolts; the rubber sleeve is closed, and integral sealing bosses are provided on both sides of the outside of the rubber sleeve.

8. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: In step 10, the airbag pressure is set to 0.35-0.4 MPa.

9. The method for trenchless repair of a drainage pipe according to claim 1, characterized in that: The appearance inspection of the repaired pipeline in step 11 should meet the following requirements: the rubber sealing ring is installed in the correct position, completely covers the defects of the repaired part, and fits tightly with the original pipeline without any visible groundwater leakage; the CCTV pipeline robot inspection shows that the inner wall of the repaired pipeline is smooth, and the rubber sealing ring fits well with the pipeline without any leakage.

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