Device and method for adding connecting wells to concrete water supply and drainage pipes in situ without water shutoff

Abstract

The present invention discloses a device and method for adding a connecting well to a concrete water supply and drainage pipe in situ without water shutoff, and belongs to the field of water supply and drainage concrete pipe connecting well construction. The device includes a connecting shaft, an old concrete pipe, a new pipe, a side support device for the old pipe, a bottom support device for the old pipe, and a connecting shaft. The old concrete pipe section whose bottom is to be hollowed out and hardened is located in the connecting shaft. A well-in-well is set at the bottom of the connecting shaft. The old concrete pipe is connected to the new pipe through the well-in-well. The side support devices for the old pipe are set on both sides of the old concrete pipe, and the bottom support device for the old pipe is set at the bottom of the old concrete pipe. The old concrete pipe section is supported by steel piles, a steel crossbeam support, and a steel wire rope suspension dual insurance method. The steel piles limit the left and right deformation and displacement of the old concrete pipe section, avoiding the phenomenon of pulling, squeezing, left and right misalignment of the old pipe section to be hollowed out, and preventing the old pipe section from suddenly cracking and leaking and instantaneous flooding of the well, thereby reducing the possibility of accidents.

Description

Technical Field

[0001] The present invention relates to the field of water supply and drainage concrete pipe connection well construction, in particular to a device and method for adding a connection well to a concrete water supply and drainage pipe in situ without water shutoff. Background Art

[0002] As the scale of cities continues to expand, the large-diameter underground reinforced concrete water supply and drainage pipes that have been put into operation in previously built-up areas are buried several meters or even dozens of meters deep, with a diameter of 1 meter or even 3 to 4 meters. They are made of 2.5-meter-long reinforced concrete standard pipe sections connected at both ends in a spigot-type socket-type. Some areas through which pipelines pass require a large amount of new infrastructure, including subways, high-rise buildings, underground parking lots, social public service venues, etc. The foundations of these new facilities should not cross the large-diameter underground reinforced concrete water supply and drainage pipe network in operation. Therefore, the reinforced concrete water supply and drainage pipes in this area need to be relocated and most of them require non-stop water supply during the relocation.

[0003] After the construction of the new large-diameter underground reinforced concrete water supply and drainage pipe is completed, it is necessary to connect to the existing upstream and downstream pipe sections. Therefore, a reinforced concrete connection well must be added near the intersection of the new large-diameter underground reinforced concrete water supply and drainage pipe and the existing upstream and downstream pipe sections. This allows all fluids flowing in the old pipe to be diverted to the new pipe. Due to the deep burial depth and large diameter of the old and new pipes, the connection well must also be deep, several meters or even dozens of meters, and its length or width must be more than 10 meters. The connecting well is an underground reinforced concrete cast-in-place structure project. During the construction of the connecting well structure, it is necessary to hollow out 6 to 9 meters of the bottom of the old reinforced concrete pipe section in operation (equivalent to 3 or 4 standard pipe sections). The old pipe section and the water in the pipe have a large dead weight, and the connecting well is deep and has a large span. It is difficult to set up temporary supports to support the old reinforced concrete pipe section in operation and provide a working surface for the hollowing and hardening of the old pipe bottom to construct the connecting well. The hollowing, hardening and connecting well structure construction takes a long time and must ensure that the large-diameter underground reinforced concrete water supply and drainage pipes can operate normally and safely without water interruption during the relocation, which is a difficult problem in the industry.

[0004] For large-diameter underground reinforced concrete water supply and drainage pipes that are hollowed out and hardened in situ without stopping water to add connecting wells, the current traditional technology is to add a sealing ring beam and set up a Bailey truss at the wellhead of the connecting shaft, cover the old reinforced concrete pipe section with a large number of thick steel wire ropes, suspend and fix the old pipe section to the wellhead of the shaft, and then directly hollow out the earth at the bottom of the old pipe to construct the connecting well bottom plate and its well-in-well structure.

[0005] The current technical disadvantages of the traditional Bailey truss to suspend the old pipe section for water-free hollowing and hardening to add a connecting well are:

[0006] (1) Narrow scope of application: The traditional Bailey truss suspension technology for old pipe sections is only applicable to the in-situ water-free hollowing and hardening of pipes with small diameters, small spans of connecting shafts, and shallow wells. It cannot be used for the in-situ water-free hollowing and hardening of pipes with large diameters (greater than 1m), large spans of connecting shafts (greater than 6m), and deep wells (greater than 6m). On the one hand, the large diameter of reinforced concrete pipes, their large loads, and large spans of connecting shafts require an increased span of Bailey trusses, which deteriorates the stress conditions of the Bailey trusses and suspension wire ropes, and the ring beams, retaining walls, Bailey trusses, and suspension wire ropes at the wellhead are overwhelmed. On the other hand, the deep connecting shafts increase the length of the suspension wire ropes, resulting in uneven stress, which can easily cause the suspended reinforced concrete pipe sections to swing back and forth or left and right, leading to sudden cracking and leakage at the pipe section joints and sudden well flooding accidents.

[0007] (2) The safety of the construction process is difficult to ensure: the traditional Bailey truss suspension pipe section technology is prone to the suspension pipe section being pulled front and back, squeezed, misaligned left and right, the Bailey truss becoming unstable, or the suspension wire rope being broken or loose, the pipe section joints suddenly cracking and leaking, and the well being flooded instantly. Once an accident occurs, timely rescue and remediation are impossible, and the economic and social losses are immeasurable, directly leading to serious accidents. Summary of the Invention

[0008] The purpose of the present invention is to provide a device and method for adding a connecting well to a concrete water supply and drainage pipe in situ without water stopping, so as to solve the technical problems of the existing method of hollowing and hardening the underground reinforced concrete water supply and drainage pipe in situ without water stopping and adding a connecting well, which has a narrow application range and is unsafe in construction. The technology mainly adopts steel pile support and a double insurance method of steel crossbeam support + wire rope suspension to double support the old pipe section to be hollowed out, hollow out the earth at the bottom of the old pipe and construct the reinforced concrete bottom plate of the connecting well, temporarily support the top with steel wedges, and construct the connecting well. Finally, the steel crossbeam, steel longitudinal beam, steel brace, steel beam, steel diagonal brace, steel wire rope and steel pile are cut off in sequence to ensure that during the process of hollowing and hardening the bottom of the old concrete pipe to add the connecting well, the old pipe section will not deform, sink or leak, thereby ensuring the normal and safe operation of the existing pipeline at full load.

[0009] A connecting well device for adding an in-situ non-stop water supply and drainage pipe comprises a connecting shaft, an old concrete pipe, a new pipe, a side support device for the old pipe, a bottom support device for the old pipe and a connecting shaft (also known as a well-in-well). The old concrete pipe section with the bottom hollowed out and hardened (referred to as the old concrete pipe or the old pipe) is located in the connecting shaft. The well-in-well is set at the bottom of the connecting shaft. The old concrete pipe is connected to the new pipe through the well-in-well. The side support devices for the old pipe are set on both sides of the old concrete pipe, and the bottom support device for the old pipe is set at the bottom of the old concrete pipe.

[0010] Furthermore, the well in the well includes a vertical well wall and a well cover. The vertical well wall is vertically arranged in the vertical well and forms a side closed structure. The well cover is arranged on the top of the vertical well wall.

[0011] Furthermore, the old pipe side support device includes concrete piers, steel piles, steel beams and steel longitudinal beams. The concrete piers are arranged at the bottom of the connecting shaft, the bottom ends of the steel piles are fixed on the concrete piers, and the steel piles are vertically arranged on both sides of the concrete old pipe and in contact with the outer wall of the concrete old pipe. The steel beams are fixed across the two steel piles and in contact with the top outer wall of the concrete old pipe, and the steel longitudinal beams are horizontally arranged between the steel piles.

[0012] Furthermore, a plurality of steel bar heads are provided at the bottom of the steel pile, and the steel bar heads are buried in the concrete pier.

[0013] Furthermore, the old pipe side support device also includes a steel brace, the upper end of the steel brace is welded and fixed to the steel pile, and the lower end is inclined on the connecting shaft guard wall, with an angle of 45 to 60 degrees to the ground. Each steel brace and the truss composed of the supported steel piles and steel beams are in the same installation plane, and each steel pile is provided with a steel brace support.

[0014] Furthermore, the bottom support device of the old pipe includes a steel beam and a steel diagonal brace. The steel beam is arranged horizontally at the bottom of the old concrete pipe and is arranged in contact with the bottom outer wall of the old concrete pipe. The steel diagonal brace is arranged at the bottom of the steel beam. The steel diagonal brace is arranged as an inverted "V" structure, and both sides of the inverted "V" structure are fixed on steel piles.

[0015] Furthermore, the bottom support device of the old pipe also includes a steel lifting ring, a steel wire rope and a steel wedge. The steel lifting ring is welded on both sides and fixed to the web of the steel pile. Each steel pile is provided with a steel lifting ring. The two ends of the steel wire rope are respectively fastened to the steel lifting ring through four rope clamps. The steel wire rope is wrapped around the bottom of the old concrete pipe and is in contact with the bottom outer wall of the old concrete pipe. The steel wedge is set on the middle and lower side of the old concrete pipe and is in contact with the outer wall of the old concrete pipe.

[0016] A method for adding a connecting well device to a concrete water supply and drainage pipe in situ without water shutoff, comprising the following steps

[0017] Step 1: Excavate the earthwork in the connecting shaft in layers and support the shaft wall to the waistline elevation of the old concrete pipe;

[0018] Step 2: Position and install steel piles. Set four steel pile points close to the outer wall of the old concrete pipe and away from the outer wall of the pipe joint. Use a geological drill to drill vertically downward close to the outer wall of the old pipe waistline. Clean the hole and pour quick-setting concrete into the hole until the concrete overflows from the hole mouth. Insert the steel pile into the hole. The concrete in the hole should be cured for more than 7 days.

[0019] Step 3: Install the steel beam. The steel beam is placed above the old concrete pipe and is installed horizontally close to the top outer wall of the old concrete pipe. The steel beam is fixed to the steel pile by welding.

[0020] Step 4: Install the steel longitudinal beams. Place the steel longitudinal beams on the adjacent steel cross beams, and weld the two ends of the steel longitudinal beams firmly to the steel piles on both sides.

[0021] Step 5: Continue excavating the earthwork in the shaft. Except for the earthwork below the projection area of ​​the old concrete pipe, which is temporarily retained, continue to excavate the shaft earthwork in layers and support the shaft retaining wall to the bottom elevation of the shaft floor cushion. While excavating, spray 50mm thick concrete on the exposed soil surface in the projection area below the old concrete pipe.

[0022] Step 6: Install the steel brace in the middle of the steel pile. The upper end of the steel brace is firmly welded to the steel pile, and the lower end is pressed against the shaft retaining wall and has an angle of 45 to 60 degrees with the ground.

[0023] Step 7: Pour the first cushion layer concrete of the connecting shaft except the projected area below the old concrete pipe.

[0024] Step 8: Steel lifting rings are installed symmetrically on both sides. A steel lifting ring is welded to the steel pile web surface at the intersection of each set of steel piles and the waistline of the old concrete pipe. The steel lifting ring and the steel pile web are fixed by double-sided welding;

[0025] Step 9: Install the wire rope. Dig a soil groove along the outer surface of the old concrete pipe between each set of steel piles symmetrically on both sides, either manually or mechanically, and put the wire rope on it. The wire rope is tightened upwards to the lower outer wall of the old concrete pipe. The two ends of the wire rope are fastened to the steel eyelets through rope clamps.

[0026] Step 10: Install the steel beam. Dig a horizontal hole manually or mechanically at the lowest point of the old concrete pipe belly between each set of steel piles symmetrically on both sides. Install the top outer side of the channel steel flange close to the lowest point of the old pipe belly for horizontal installation. Weld the webs of the two ends of the steel beam and the steel piles on the left and right sides tightly against each other on both sides.

[0027] Step 11: Install the steel diagonal brace. On the soil side between each set of steel piles, dig out an "eight"-shaped soil groove manually or mechanically, insert the steel diagonal brace, and press the upper end of the steel diagonal brace against the limit steel plate at the bottom of the steel beam. The lower end of the steel diagonal brace is obliquely crossed with the steel pile and welded firmly.

[0028] Step 12: Manually excavate the projected area directly below the old concrete pipe to the bottom elevation of the shaft cushion layer and pour the second cushion layer concrete.

[0029] Step 13: Connect the shaft floor structure, construct the shaft floor reinforced concrete, and pre-embed the steel bars of the shaft wall;

[0030] Step 14: Cut off the steel diagonal bracing and chisel out and fill the holes;

[0031] Step 15: Build a new reinforced concrete water supply and drainage pipe and extend it into the well;

[0032] Step 16: Construction of reinforced concrete structure of vertical wall of well in well;

[0033] Step 17: Fabrication and installation of steel wedges. After the reinforced concrete floor and the vertical wall of the well are completed, and before the local rope saw cuts in the old concrete pipe are connected and the old pipe section is lifted out, steel wedges are inserted into the gap between the concrete floor and the old concrete pipe as temporary supports. One steel wedge is inserted near the steel pile of each section of the old pipe.

[0034] Step 18: Quality inspection of newly constructed reinforced concrete water supply and drainage pipes, connecting shafts and wells within wells; removal of steel beams, longitudinal beams, diagonal braces, steel beams, steel wire ropes and steel piles; and clearing and filling of holes;

[0035] Step 19: Use a wire saw to cut off and lift out part of the old pipe section in the well to form a communication channel for the fluid of the new and old pipes;

[0036] Step 21: Lift off the steel wedges and seal the old abandoned inlet and outlet pipes in the well, construct the well cover and install the wellbore, and backfill the earth layer by layer to the ground to complete the work.

[0037] The present invention adopts the above technical solution, and the present invention has the following technical effects:

[0038] The present invention is suitable for in-situ water-free hollowing and hardening of pipelines with small diameters, vertical shaft spans and well depths, and is also suitable for in-situ water-free hollowing and hardening of pipelines with large diameters (greater than 1m), large vertical shaft spans (greater than 6m) and deep well depths (greater than 6m). The stress and deformation requirements can be met by simply adjusting the specifications of steel piles, steel crossbeams, steel longitudinal beams, steel castors, steel lifting rings, steel wire ropes, steel beams, steel diagonal braces and steel wedges through calculation. Steel piles and a double insurance method of steel crossbeam lower supports + steel wire rope suspension are used to provide double support for the old pipe section to be hollowed out. The steel piles limit the left and right deformation and displacement of the old pipe section to be hollowed out, avoiding front and rear pulling cracks, squeeze cracks, left and right misalignment of the old pipe section to be hollowed out, and avoiding the phenomenon of sudden cracking and leakage of the old pipe section and instantaneous flooding of the well, thereby reducing the possibility of accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a plan view of the connection well of the present invention.

[0040] Figure 2 It is a cross-sectional view of the connecting well of the present invention after the steel piles, steel cross beams and steel longitudinal beams are installed.

[0041] Figure 3 It is a cross-sectional view of the present invention after the earthwork is excavated to the bottom of the base plate cushion layer.

[0042] Figure 4 It is a cross-sectional view of the temporary fixing frame of the present invention after installation.

[0043] Figure 5It is a cross-sectional view of the old pipe bottom after being hollowed out according to the present invention.

[0044] Figure 6 It is a cross-sectional view of the well bottom plate after connection of the present invention is completed.

[0045] Figure 7 It is a cross-sectional view of the present invention after the vertical wall is completed and the steel wedges are in place.

[0046] Figure 8 It is a cross-sectional view of the connection well, connection and project completion of the present invention.

[0047] Numbers in the figure: 1-original ground; 2-shaft retaining wall; 3-old concrete pipe; 4-concrete pier; 5-rebar head; 6-steel pile; 7-steel crossbeam; 8-steel longitudinal beam; 9-steel guy support; 10-steel lifting ring; 11-steel wire rope; 12-steel beam; 13-steel diagonal brace; 14-first cushion layer; 15-second cushion layer; 16-steel wedge; 17-new pipe; 18-vertical wall in the well; 19-well cover in the well; 20-pipeline joint. DETAILED DESCRIPTION

[0048] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, preferred embodiments are given and the present invention is further described in detail. However, it should be noted that many of the details listed in the specification are merely provided to help the reader have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be practiced even without these specific details.

[0049] A device for adding a connecting well to a concrete water supply and drainage pipe in situ without stopping water, such as Figures 1-8 As shown, it includes a connecting shaft, an old concrete pipe 3, a new pipe 17, a side support device for the old pipe, a bottom support device for the old pipe and a connecting shaft (also called a well in a well). The old concrete pipe section 3 (referred to as the old concrete pipe or the old pipe) with the bottom hollowed out and hardened is located in the connecting shaft. The well in a well is set at the bottom of the connecting shaft. The old concrete pipe 3 is connected to the new pipe 17 through the well in a well. The side support devices of the old pipe are set on both sides of the old concrete pipe 3, and the bottom support device of the old pipe is set at the bottom of the old concrete pipe 3. The connecting shaft in the embodiment of the present invention is a reinforced concrete circular well with an inner diameter of 12 meters and a depth of 16 meters. There is a side protection guardrail at the wellhead. 11.54 meters above the ground is a reinforced concrete sewage main pipe with an inner diameter of DN2800 and a daily flow rate of 400,000 cubic meters in operation (hereinafter referred to as the old pipe). The top of the old pipe is 11.54 meters deep from the ground and the wall thickness of the old pipe is 0.28 meters. The old pipe is not allowed to be shut down. The old pipe is obliquely crossed with the newly built DN2800 reinforced concrete sewage main (hereinafter referred to as the new pipe). Figure 1 and Figure 2As shown, the old and new pipes are essentially on the same datum plane. The old pipe bottom must be hollowed out and hardened without stopping the water flow, and a connecting well (i.e., a well within a well) must be constructed. Within the well within the well, all sewage from the old pipe will be connected to the new pipe, and the abandoned ends of the old pipe must be sealed. This means that during the entire sewage pipe relocation period, sewage in the old pipe must flow unimpeded 24 hours a day.

[0050] The old reinforced concrete pipe 3 is located several meters or tens of meters below the ground. It is composed of multiple standard reinforced concrete pipes connected end to end in a socket-and-spigot style. Each standard pipe section is 2.5 meters long, with an inner diameter of 2.8 meters and a wall thickness of 0.28 meters. It is an existing underground concrete water supply and drainage pipe in operation and should not be shut down all year round.

[0051] In the embodiment of the present invention, the well-in-well includes a well-in-well vertical wall 18 and a well cover 19. The well-in-well vertical wall 18 is vertically arranged in the vertical shaft and forms a side closed structure. The well cover 19 is arranged on the top of the well-in-well vertical wall 18. This technology has a wide range of applications in the field of municipal engineering construction and can ensure construction safety. It is suitable for all types of underground reinforced concrete water supply and drainage pipes with different diameters, vertical shaft spans and well depths to hollow out and harden them in situ without stopping water and add connecting wells. Steel piles limit the left and right displacement of the old pipe section to be hollowed out. At the same time, a double insurance method of steel crossbeam support + wire rope suspension is used to double support the old pipe section to be hollowed out. It can meet the requirements of the dead weight of the old pipe body and the fluid in the pipe and limit its deformation, avoid deformation, dislocation and collapse of the old pipe section to be hollowed out, and avoid cracking, leakage and instant flooding of the well, thereby reducing the possibility of accidents.

[0052] In an embodiment of the present invention, the old pipe side support device includes a concrete pier 4, a steel pile 6, a steel crossbeam 7 and a steel longitudinal beam 8. The concrete pier 4 is arranged at the bottom of the connecting shaft, the bottom end of the steel pile 6 is fixed on the concrete pier 4, and the steel piles 6 are vertically arranged on both sides of the concrete old pipe 3 and are in contact with the outer wall of the waistline of the concrete old pipe 3. The steel crossbeam 7 is fixed across the two steel piles 6 and is in contact with the top of the concrete old pipe 3. The steel longitudinal beam 8 is horizontally arranged between the steel piles 6 and the steel piles 6. The steel pile 6 is 28#b hot-rolled ordinary channel steel with a length of 9m. HRB400 steel bar heads with a diameter of 25mm @ 400mm are welded on both sides of the 3.82m length area of ​​the channel steel root. The root of the channel steel is formed into a mace shape. The channel steel model and length are determined by design calculations. At the bottom of the well, on the outside of each section of the old pipe, four steel pile points are set on the outer pipe wall side close to the old pipe wall and 800mm away from its pipe section interface. A geological exploration drilling rig is used to drill a vertical hole downward close to the side wall of the waistline of the concrete old pipe 3. The hole diameter is 0.5m and the hole depth is 6.82m. After pouring C25 quick-setting concrete into the hole, the channel steel at the root of the steel pile 6 is inserted into the concrete in the hole to a certain depth and then cured for not less than 7 days.

[0053] In the embodiment of the present invention, a plurality of steel bar heads 5 are provided at the bottom of the steel pile 6 , and the steel bar heads 5 are buried in the concrete pier 4 .

[0054] In the embodiment of the present invention, the side support device of the old pipe also includes a steel brace 9. The upper end of the steel brace 9 is welded and fixed to the steel pile 6, and the lower end is tilted and arranged on the shaft guard wall 2, with an angle of 45 to 60 degrees with the ground. Each steel brace 9 and the truss composed of the supported steel pile 6 and the steel beam 7 are in the same installation plane, and each steel pile 6 is supported by a steel brace 9. The steel beam 7 is 18#b hot-rolled ordinary channel steel with a length of 4m. Its model and length are determined by design calculations. It is located above the old pipe 3 and is installed horizontally and horizontally close to the outer wall of the concrete pipe. The steel beam is welded and fixed to the steel pile.

[0055] In an embodiment of the present invention, the bottom support device of the old pipe includes a steel beam 12 and a steel diagonal brace 13. The steel beam 12 is horizontally arranged at the bottom of the old concrete pipe 3 and is arranged in contact with the bottom outer wall of the old concrete pipe 3. The steel diagonal brace 13 is arranged at the bottom of the steel beam 12. The steel diagonal brace 13 is arranged as an inverted "V" structure, and the two sides of the inverted "V" structure are welded and fixed on the steel pile 6.

[0056] In an embodiment of the present invention, the bottom support device of the old pipe also includes a steel lifting ring 10, a steel wire rope 11 and a steel wedge 16. The steel lifting ring 10 is welded on both sides and fixed to the web of the steel pile 6. Each steel pile 6 is provided with a steel lifting ring 10. The two ends of the steel wire rope 11 are respectively fastened to the steel lifting ring 10 through four rope clamps. The steel wire rope 11 is wrapped around the bottom of the concrete old pipe 3 and is in contact with the bottom outer wall of the concrete old pipe 3. The steel wedge 16 is arranged on the middle and lower side of the concrete old pipe 3 and is in contact with the outer wall of the concrete old pipe 3.

[0057] The steel longitudinal beam 8 is 18#b hot-rolled ordinary channel steel with a length of about 2m. Its model is determined by design calculation. The channel steel wing plate is placed on the adjacent steel cross beam 7. The two ends of the steel longitudinal beam are firmly welded to the steel piles on both sides, which plays the role of fixing the steel cross beam and steel piles and forming a truss to prevent the truss from deforming in the front and rear directions.

[0058] The steel guy brace 9 is 18#b hot-rolled ordinary channel steel, the model of which is determined by design calculation and the length is determined on site. The upper end of the steel guy brace is welded and fixed to the steel pile 6, and the lower end is tightly connected to the vertical shaft guard wall, with an angle of 45 to 60 degrees to the ground. Each steel guy brace and the truss composed of the supported steel beams and steel piles are in the same installation plane, and each steel pile is provided with a steel guy brace to prevent the truss from deforming in the left and right directions.

[0059] The steel ring 10 is a U-shaped steel bar made of 22mm diameter HPB300. Its model and length are determined by design calculation. It is welded on both sides and fixed to the web of the steel pile 6. Each steel pile is provided with a steel ring.

[0060] The steel wire rope 11 is a multi-strand steel core steel wire rope with a diameter of 28 mm. Its model and length are determined by design calculations. Its two ends are respectively fastened to the steel hanging ring 10 through four rope clamps to suspend the old concrete pipe.

[0061] The steel beam 12 is 28#b hot-rolled ordinary channel steel with a length of 4.5m. Its model and length are determined by design calculation. It is close to the outer side of the belly wall of the old concrete pipe 3, and its two sides are welded and fixed to the steel piles 6 to bear the weight of the old concrete pipe. It and the steel wire rope 11 suspend the old concrete pipe to serve as a double insurance to ensure that the running old concrete pipe will not deform, sink or leak during the period of hollowing out the bottom of the old pipe and hardening and adding a connecting well.

[0062] The steel diagonal brace 13 is 18#b hot-rolled ordinary channel steel with a length of 2.2m. Its model and length are determined by design calculation. The upper end of the steel diagonal brace is pressed against the limiting steel plate on the belly of the steel beam 12, and the lower end is obliquely crossed with the steel pile 6 and welded and fixed. It supports the middle part of the steel beam 12 and increases the rigidity.

[0063] The steel wedge 16 is a triangular washer with a length of 1m, a width of 0.6m and a height of 0.6m. The surface is welded with 10mm thick steel plates, and a grouting hole with a diameter of 150mm is reserved on the side. The interior of the steel wedge is densely filled with C60 concrete. The material and external dimensions of the steel wedge are determined by design calculations. After the reinforced concrete bottom plate of the connecting well and the vertical wall of the well in the well are completed, and before the local rope saw break of the concrete old pipe is connected and the old pipe section is lifted off, the steel wedge is used as a temporary support within the height range of the gap between the concrete bottom plate and the concrete old pipe. A steel wedge is inserted near the steel piles of each section of the concrete old pipe to safely cut off the steel crossbeams, steel longitudinal beams, steel braces, steel beams, steel diagonal braces, steel ropes and steel piles in turn.

[0064] A method for adding a connecting well device to a concrete water supply and drainage pipe in situ without water shutoff, comprising the following steps:

[0065] Step 1: Connect the shaft excavation and support, and then excavate the soil in the shaft layer by layer and retain the wall until the old pipe waistline elevation is reached. At this time, the old pipe waistline elevation is 13.22m deep from the ground. Figure 2 shown.

[0066] Step 2: Positioning and installation of steel piles. On the outside of each old pipe section, four steel piles are set up on the outer wall of the old pipe, close to the old pipe wall and 800mm away from the pipe section interface. The steel piles are 28#b hot-rolled ordinary channel steel with a length of L=9m. HRB400 steel bar heads with a diameter of 25 are welded horizontally on both sides of the 3820mm section at the root of each steel pile. The length of each steel bar head is 400mm, and the vertical spacing is 400mm, forming a mace shape to increase the bonding strength between the steel pile and the C25 concrete. Improve the vertical bearing capacity of steel piles; use a geological drill to drill vertically downwards close to the outer wall of the old pipe waistline, with a hole diameter of 0.5m and a hole depth of 6.82m; clean the hole and pour C25 quick-setting concrete into the hole until the concrete overflows from the hole mouth; insert the steel pile into the hole, with the steel pile inserted 6.82m into the hole and 2.18m exposed, and install the outer side of the channel steel wing plate close to the outer side of the old pipe waistline for vertical installation; the concrete in the hole is cured for more than 7 days, ensuring that each side of each section of the old pipe has two steel piles for vertical side protection, such as Figure 1 and Figure 2 shown.

[0067] Step 3: Installation of steel beams. The steel beams are made of 18#b hot-rolled ordinary channel steel with a length of L=4m. The outer side of the channel steel flange is installed horizontally and close to the highest point of the old pipe outer wall. The webs of the two ends of the steel beam and the steel piles on the left and right sides are welded tightly. Figure 2 shown.

[0068] Step 4: Installation of steel longitudinal beams. Steel longitudinal beams are made of 18#b hot-rolled ordinary channel steel with a length of L=2m. The channel steel flanges are placed on the adjacent steel beams. The two ends of the steel longitudinal beams are welded firmly to the steel piles on both sides to fix the steel beams and piles and form a truss. Figure 2 shown.

[0069] Step 5: Continue to excavate the soil in the shaft, except for the area below the projection of the old pipe, to the bottom elevation of the shaft bottom slab. The soil thickness is about 3m. While excavating, spray 50mm thick C20 concrete on the exposed soil surface of the projection area below the old pipe to ensure the temporary stability of the slope. Figure 3 shown.

[0070] Step 6: Installation of steel bracing. Install steel bracing in the middle of each steel pile. The steel bracing is made of 18#b hot-rolled ordinary channel steel. The upper end of the steel bracing is obliquely crossed with the steel pile web and welded firmly. The lower end is pressed against the shaft retaining wall and has an angle of 45 to 60 degrees with the ground. Its length is determined according to the actual needs of the site. Each steel bracing and the truss composed of the supported steel beam and steel pile are in the same installation plane. Figure 4 shown.

[0071] Step 7: pouring the first cushion layer 14 , that is, pouring the first cushion layer 14 except the projection area below the old concrete pipe 3 .

[0072] Step 8: Installation of steel lifting rings. Steel lifting rings are made of 22 HPB300 steel bars with a length of L=900mm and bent into a U-shape. The inner diameter is 150mm and each leg is 300mm long. A steel lifting ring is welded on the surface of the steel pile web where each group of steel piles intersects with the waistline of the old pipe. The steel lifting rings and the steel pile web are fixed by double-sided welding. Figure 4 shown.

[0073] Step 9: Installation of wire rope. The wire rope adopts multi-strand steel core wire rope with diameter of 28mm. Dig a 100mm diameter soil groove along the outer surface of the old concrete pipe 3 between each group of steel piles symmetrically on both sides, and put the wire rope on it. The wire rope is tightened upwards to the lower outer wall of the old pipe. The two ends of the wire rope are respectively fastened to the steel ring through 4 rope clamps. Figure 4 shown.

[0074] Step 10: Installation of steel beams. The steel beams are made of 28#b hot-rolled ordinary channel steel with a length of L=4.5m. A 10mm thick, 100X100mm limiting steel plate is welded on the lower side of the middle of the steel beam 12. A horizontal hole with a diameter of about 350mm is dug out manually or mechanically near the lowest point of the belly of the old concrete pipe 3 between each group of steel piles symmetrically on both sides. The outer side of the top of the channel steel flange is installed horizontally close to the lowest point of the belly of the old pipe. The webs of the two ends of the steel beam and the steel piles on the left and right sides are tightly welded on both sides. Figure 4 shown.

[0075] Step 11: Installation of steel diagonal bracing. The steel diagonal bracing is made of 18#b hot-rolled common channel steel with a length of L=2.2m. On the soil side between each set of steel piles, diagonal "eight" shaped soil grooves with a width of about 350mm are dug manually or mechanically. The steel diagonal bracing is inserted. The upper end of the steel diagonal bracing is pressed against the limit steel plate at the lower edge of the steel beam. The lower end of the steel diagonal bracing is obliquely crossed with the steel piles and welded firmly. Figure 4 shown.

[0076] Step 12: Manually excavate the projected area directly below the old concrete pipe 3 to the bottom elevation of the shaft cushion layer and pour the second cushion layer 15, as shown in the following figure: Figure 5 shown.

[0077] Step 13: Connect the shaft bottom plate structure, construct the shaft bottom plate 1m thick C30 reinforced concrete and pre-embed the vertical wall steel bars in the well, such as Figure 6 shown.

[0078] Step 14: Cut off the steel diagonal braces and chisel out and fill the holes to prevent future rust and water leakage from the base plate.

[0079] Step 15: Build new reinforced concrete water supply and drainage pipes and extend them into the well.

[0080] Step 16: Construction of reinforced concrete structure of vertical wall of well in well, such as Figure 7 shown.

[0081] Step 17: Installation of steel wedges. Each steel wedge is a triangular pad with a length of 1m, a width of 0.6m and a height of 0.6m. The surface is welded with 10mm thick steel plates, and a grouting hole with a diameter of 150mm is reserved on the side. The inside of the steel wedge is filled and compacted with C60 concrete. After the reinforced concrete bottom plate and the vertical wall of the well are completed, and before the local rope saw break of the concrete old pipe is connected and the old pipe section is lifted off, the steel wedge is inserted into the height range of the gap between the concrete bottom plate and the concrete old pipe as a temporary support. A steel wedge is inserted near the steel pile of each section of the old pipe. Each set of steel wedges is welded to a pair on both sides with two 18#b I-beams to form a tensioning shape, so as to support the weight of the old pipe and the fluid in the pipe and ensure the stability of the old pipe, and provide a safe working space for the safe removal of steel beams, steel longitudinal beams, steel bracing, steel beams, steel diagonal bracing, steel ropes and steel piles in sequence. Figure 7 shown.

[0082] Step 18: Quality acceptance of newly built reinforced concrete water supply and drainage pipes, connecting shafts and wells within wells.

[0083] Step 19: Cut off the steel beams, steel longitudinal beams, steel braces, steel beams, steel wire ropes and steel piles and clean and fill the holes to prevent rust and water leakage in the future. Figure 8 shown.

[0084] Step 20: Use a wire saw to cut off and lift out part of the old pipe section in the well to form a connecting channel for the fluid of the new and old pipes.

[0085] Step 21: Lift off the steel wedge and seal the old abandoned inlet and outlet pipes in the well.

[0086] Step 22: Construction of the well cover and wellbore installation and backfilling of earthwork to the ground in layers. Figure 8 shown.

[0087] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for adding a connecting well device to a concrete water supply and drainage pipe in situ without stopping water, characterized by: A well connection device comprises a connecting shaft, an old concrete pipe (3), a new pipe (17), a side support device for the old pipe, a bottom support device for the old pipe, and a well in a well, wherein the old concrete pipe (3) whose bottom is hollowed out and hardened is located in the connecting shaft, the well in a well is arranged at the bottom of the connecting shaft, the old concrete pipe (3) is connected to the new pipe (17) through the well in a well, the side support devices for the old pipe are arranged on both sides of the old concrete pipe (3), and the bottom support device for the old pipe is arranged at the bottom of the old concrete pipe (3); The well in the well comprises a well in the well vertical wall (18) and a well cover plate (19), wherein the well in the well vertical wall (18) is vertically arranged in the connecting vertical shaft and forms a side closed structure, and the well cover plate (19) is arranged on the top of the well in the well vertical wall (18); The old pipe side support device includes a concrete pier (4), a steel pile (6), a steel crossbeam (7) and a steel longitudinal beam (8), wherein the concrete pier (4) is arranged at the bottom of the connecting shaft, the bottom end of the steel pile (6) is fixed on the concrete pier (4), and the steel pile (6) is vertically arranged on both sides of the concrete old pipe (3) and is tightly arranged with the waistline of the concrete old pipe (3), the steel crossbeam (7) is fixed across the two steel piles (6) and is in contact with the top outer wall of the concrete old pipe (3), and the steel longitudinal beam (8) is horizontally arranged between the steel piles (6); A plurality of steel bar heads (5) are provided at the bottom of the steel pile (6), and the steel bar heads (5) are buried in the concrete pier (4); The old pipe side support device also includes a steel brace (9), the upper end of the steel brace (9) is welded and fixed to the steel pile (6), and the lower end is tilted and arranged on the connecting shaft retaining wall (2), with an angle of 45 to 60 degrees with the ground. Each steel brace (9) and the truss composed of the supported steel pile (6) and the steel beam (7) are in the same installation plane, and each steel pile (6) is provided with a steel brace (9) for support; The old pipe bottom support device includes a steel beam (12) and a steel diagonal brace (13). The steel beam (12) is arranged transversely at the bottom of the old concrete pipe (3) and is arranged in contact with the bottom outer wall of the old concrete pipe (3). The steel diagonal brace (13) is arranged at the bottom of the steel beam (12). The steel diagonal brace (13) is arranged in an inverted "V"-shaped structure. Both sides of the inverted "V"-shaped structure are welded and fixed on the steel pile (6). The old pipe bottom support device also includes a steel ring (10), a steel wire rope (11) and a steel wedge (16). The steel ring (10) is welded on both sides and fixed to the web of the steel pile (6). Each steel pile (6) is provided with a steel ring (10). The two ends of the steel wire rope (11) are respectively fastened to the steel ring (10) through four rope clamps. The steel wire rope (11) holds the bottom of the concrete old pipe (3) and is in contact with the bottom outer wall of the concrete old pipe (3). The steel wedge (16) is provided on the middle and lower side wall of the concrete old pipe (3) and is in contact with the outer wall of the concrete old pipe (3). The method comprises the following steps: Step 1: Excavate the earthwork in the connecting shaft in layers and support the shaft wall to the waistline elevation of the old concrete pipe; Step 2: Position and install steel piles. Set four steel pile points close to the wall of the old concrete pipe and away from the outer wall of the pipe joint. Use a geological drill to drill vertically downward close to the outer wall of the old pipe waistline. Clean the hole and pour quick-setting concrete into the hole until the concrete overflows from the hole mouth. Insert the steel pile into the hole. The concrete in the hole should be cured for more than 7 days. Step 3: Install the steel beam. The steel beam is placed above the old concrete pipe and installed horizontally close to the outer wall of the old concrete pipe. The steel beam is fixed to the steel pile by welding. Step 4: Install the steel longitudinal beams. Place the steel longitudinal beams on the adjacent steel cross beams. Weld and fix the two ends of the steel longitudinal beams to the steel piles on both sides. Step 5: Continue excavating the earthwork in the shaft. Except for the earthwork in the projection area of ​​the old concrete pipe, which is temporarily retained, continue to excavate the shaft earthwork in layers and support the shaft retaining wall to the bottom elevation of the shaft floor cushion. While excavating, spray 50mm thick concrete on the exposed soil surface in the projection area below the old concrete pipe. Step 6: Install the steel brace in the middle of the steel pile. The upper end of the steel brace is firmly welded to the steel pile, and the lower end is tightly connected to the shaft retaining wall and has an angle of 45 to 60 degrees with the ground. Step 7: Pour the first cushion layer of the shaft except the projected area below the old concrete pipe; Step 8: Steel lifting rings are installed symmetrically on both sides. A steel lifting ring is welded to the steel pile web surface at the intersection of each set of steel piles and the waistline of the old concrete pipe. The steel lifting ring and the steel pile web are fixed by double-sided welding; Step 9: Install the wire rope. Dig a soil groove along the outer surface of the old concrete pipe between each set of steel piles symmetrically on both sides, either manually or mechanically, and put the wire rope on it. The wire rope is tightened upwards to the lower outer wall of the old concrete pipe. The two ends of the wire rope are fastened to the steel eyelets through rope clamps. Step 10: Install the steel beam. Dig a horizontal hole manually or mechanically at the lowest point of the old concrete pipe belly between each set of steel piles symmetrically on both sides. Install the top outer side of the channel steel flange close to the lowest point of the old pipe belly for horizontal installation. The webs of the two ends of the steel beam and the steel piles on the left and right sides are welded tightly to the webs for double-sided fixation. Step 11: Install the steel diagonal brace. On the soil side between each set of steel piles, dig out an "eight"-shaped soil groove manually or mechanically, insert the steel diagonal brace, and press the upper end of the steel diagonal brace against the limit steel plate at the bottom edge of the steel beam. The lower end of the steel diagonal brace is obliquely crossed with the steel pile and welded firmly. Step 12: Manually excavate the projected area directly below the old concrete pipe to the bottom elevation of the shaft cushion and pour the second cushion; Step 13: Construction of the shaft bottom plate structure, construction of reinforced concrete for the shaft bottom plate and pre-embedded steel bars for the vertical wall of the shaft; Step 14: Cut off the steel diagonal bracing and chisel out and fill the holes; Step 15: Build a new reinforced concrete water supply and drainage pipe and extend it into the well; Step 16: Construction of reinforced concrete structure of vertical wall of well in well; Step 17: Fabrication and installation of steel wedges. After the reinforced concrete floor and the vertical wall of the well are completed, and before the local rope saw cuts in the old concrete pipe are connected and the old pipe section is lifted out, steel wedges are inserted into the gap between the concrete floor and the old concrete pipe as temporary supports. One steel wedge is inserted near the steel pile of each section of the old pipe. Step 18: Quality inspection of newly constructed reinforced concrete water supply and drainage pipes, connecting shafts and wells within wells; removal of steel beams, longitudinal beams, diagonal braces, steel beams, steel wire ropes and steel piles; and clearing and filling of holes; Step 19: Use a wire saw to cut off and lift out part of the old pipe section in the well to form a connecting channel for the fluid of the new and old pipes; Step 21: Lift off the steel wedges and seal the old abandoned inlet and outlet pipes in the well, construct the well cover and install the wellbore, and backfill the earth layer by layer to the ground to complete the work.

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