A construction technology of prestressed steel cylinder concrete pipe

Abstract

The invention relates to the technical field of concrete pipe construction, in particular to a prestressed steel cylinder concrete pipe construction process; the invention comprises the following steps: S1: prefabricating concrete pipe seats: designing a casting mold of a concrete pipe seat according to the size of a prefabricated PCCP pipe, and obtaining a required concrete pipe seat by pouring concrete; S2: excavating a foundation trench: when the foundation trench is excavated to an elevation close to the elevation of the top surface of a U-shaped trench, leveling the bottom of the foundation trench; and then excavating the U-shaped trench; S3: installing concrete pipe seats: placing concrete pipe seats in the U-shaped trench; installing three prefabricated concrete pipe seats under each section of the PCCP pipe; S4: installing the PCCP pipe: after the PCCP pipe is suspended and placed on the concrete pipe seat, measuring the elevation and position, and adjusting the elevation and position of the PCCP pipe; S5: casting concrete pipe seats: after the PCCP pipe is installed, pouring concrete between two adjacent prefabricated concrete pipe seats below the PCCP pipe; the invention digs a U-shaped trench at the bottom of the foundation trench; and places the prefabricated concrete pipe seat in the U-shaped trench; while ensuring that the construction depth of the PCCP pipeline remains unchanged; and reducing the excavation depth of the foundation trench.

Description

Technical Field

[0001] The invention relates to the technical field of concrete pipe construction, in particular to a prestressed steel cylinder concrete pipe construction process. Background Art

[0002] Prestressed Concrete Cylinder Pipe (PCCP for short) is a product used for large-scale cross-regional water diversion projects, urban tap water, industrial water, water supply and distribution networks of agricultural irrigation systems, and circulating water pipelines of power plants; Prestressed Concrete Cylinder Pipe (PCCP for short) refers to a water pipe made by winding annular prestressed steel wire on a high-strength concrete pipe core with a steel cylinder, and then spraying a dense cement mortar protective layer on it; The standard section length of PCCP pipe is generally 5 meters; PCCP pipelines are connected by PCCP pipes; The conventional construction process of traditional PCCP pipelines is: excavation of foundation trench (pit) → acceptance of foundation trench → pouring of PCCP pipeline lower foundation concrete → installation of PCCP pipe (concrete wedges need to be prefabricated in advance) → pouring of PCCP pipeline upper foundation concrete → organization of subsequent construction processes;

[0003] However, during the conventional construction of PCCP pipelines, the excavation width and depth of the foundation pit are often large. As the foundation pit is continuously excavated, the soil's supporting capacity continues to weaken, especially when the soil quality is poor and the soil moisture is high. The slope will become more unstable, which will lead to collapse accidents, resulting in increased safety hazards. Moreover, as the foundation pit is dug deeper, not only will the corresponding slope treatment, support structure, and earthwork transportation increase, but the construction time will also be greatly extended, thereby reducing work efficiency. Moreover, as the foundation pit deepens, in order to ensure the stability and safety of the foundation pit, the foundation pit support structure needs to be strengthened, which will lead to an increase in project investment.

[0004] In view of this, in order to overcome the above technical problems, the present invention proposes a prestressed steel cylinder concrete pipe construction process to solve the above technical problems. Summary of the invention

[0005] In order to make up for the shortcomings of the prior art, the present invention proposes a prestressed steel cylinder concrete pipe construction process. The present invention excavates a U-shaped groove at the bottom of the foundation trench; thereby facilitating the user to put the prefabricated concrete pipe seat into the U-shaped groove; under the premise of ensuring that the center of the PCCP pipeline is at a certain height from the ground; the excavation depth of the foundation trench is greatly reduced; on the one hand, the engineering volume per linear meter is: Figure 1 The excavation volume of the foundation pit reached 321.12m 3 , attached Figure 2 The excavation volume of the foundation pit reached 279.38m 3 , reducing the excavation and backfilling of foundation pit by 279.38m3 On the other hand, the PCCP pipe C25 concrete pipe seat foundation is attached Figure 1 The excavation volume of the foundation pit reached 6.13m 3 , attached Figure 2 The excavation volume of the foundation pit reached 4.02m 3 , reducing the excavation and backfilling of foundation pit by 2.11m 3 ; and in terms of construction efficiency, each standard section was completed ahead of schedule.

[0006] The technical solution adopted by the present invention to solve the technical problem is: a prestressed steel cylinder concrete pipe construction process described in the present invention comprises the following steps:

[0007] S1: Prefabricated concrete pipe seat: The casting mold of the concrete pipe seat is designed according to the size of the prefabricated PCCP pipe, so as to manufacture a concrete pipe seat mold with a support angle of 120° and a length of 300-500mm; then the required concrete pipe seat is cast according to the concrete pipe seat mold;

[0008] S2: Excavation of foundation trench: According to the slope ratio requirements (1:1.5 on the left, 1:2 on the right), the foundation trench is excavated in sections and layers, and the excavation depth of each layer does not exceed 3.0m. When the elevation is close to the elevation of the top surface of the U-shaped trench, the bottom of the foundation trench is leveled; after leveling, the U-shaped trench is positioned according to the size of the prefabricated concrete pipe seat, and excavation is carried out;

[0009] S3: Installation of concrete pipe seats: Prefabricated concrete pipe seats need to be preliminarily inspected for appearance; concrete pipe seats with serious honeycombs, pitting, damage, cracks, etc. shall not be used; and according to the PCCP pipe standard 5m pipe, three prefabricated concrete pipe seats are installed by crane for each section of pipe, located in the middle of the pipe and 250mm away from the edge of the pipe;

[0010] S4: Install PCCP pipe: Use two nylon straps of equal length to hang the PCCP pipe horizontally; Hang the PCCP pipe to the concrete pipe seat; Measure the elevation and position, and use medium-coarse sand to adjust the position and elevation of the precast concrete pipe seat for rough adjustment; and add thin steel pads to the contact surface between the PCCP pipe and the concrete pipe seat for fine adjustment to adjust the elevation position of the PCCP pipe;

[0011] S5: Cast-in-place concrete pipe seat: After the PCCP pipe is installed, concrete is poured between the two adjacent precast concrete pipe seats under each pipe section; thus, a cast-in-place concrete pipe seat is formed between the two adjacent precast concrete pipe seats, with a length of 2000 to 3600 mm.

[0012] Preferably, the method for pouring the concrete pipe seat in S1 further comprises:

[0013] S11: Since the mold is divided into a lower mold and an upper mold; and a pouring hole and an exhaust hole are opened at the upper end of the upper mold; and a reserved hole is opened in the middle of the pouring hole and the exhaust hole; firstly, the lower mold is placed on the vibrating table, and then the upper mold is fixed to the upper end of the lower mold by bolts; then, the concrete pouring pipe is inserted from the pouring hole; concrete is poured until the exhaust hole overflows with concrete; and the Ω-shaped round steel lifting ring is installed in the reserved hole in the middle of the two holes;

[0014] S12: After the installation of the round steel lifting ring is completed; start the vibrating table to vibrate the concrete, and continuously add concrete until the concrete is vibrated and compacted; let the concrete in the mold stand for a period of time until the concrete solidifies and reaches 2.5MPa; lift the upper mold through the round steel lifting ring; and cure the concrete in the lower mold for 14 days; when the concrete strength reaches 75% of the design strength, remove the lower mold;

[0015] Preferably, the method for excavating the foundation trench in S2 is: before excavation, a temporary drainage ditch needs to be excavated on the left side of the slope. During excavation, an excavator is used to excavate the left side of the top surface of the U-shaped trench to the bottom at a designed slope ratio of 1:1. When the excavation elevation is close to 15 cm from the base of the U-shaped trench, the earthwork is cleaned manually, and a water collection well is excavated at the end of the U-shaped trench to collect water in the U-shaped trench into the water collection well for easy discharge.

[0016] Preferably, the method for installing the PCCP pipe in S4 is: the PCCP pipe is installed by the inner pulling method, a channel steel beam is fixed at the gap between the sockets of the two installed pipe sections, the pipe to be installed is fixed with a wire rope and a channel steel beam, and a hand winch is used on the inside of the pipe to gradually tighten the pipe to be installed to achieve the butt joint of the sockets and complete the pipe installation, thereby gradually advancing the construction process.

[0017] Preferably, an arc-shaped groove is provided at the upper end of the concrete pipe seat; and a flange is fixedly connected to the outer wall of the PCCP pipe.

[0018] Preferably, a semicircular groove is provided at the lower end of the concrete pipe seat; a roller is rotatably connected in the semicircular groove; and the roller is formed by casting concrete.

[0019] Preferably, the flange is made of high carbon steel material; the cross-sectional shape of the flange is set to be an "X" shape; an arc-shaped cavity is opened inside the flange; a feed port connected to the arc-shaped cavity is opened outside the flange; and an air diffusion hole is opened at the upper end of the flange.

[0020] Preferably, connecting pipes are installed on both sides of the flange; the connecting pipes are connected to the arc-shaped cavity in the flange; an airway is opened inside the concrete pipe seat; one end of the airway is connected to the semicircular groove; and the other end is connected to the arc-shaped groove.

[0021] Preferably, guide grooves communicating with the airway are provided on both sides of the arc-shaped groove; the guide grooves are in the shape of a frustum.

[0022] Preferably, the lower end of the upper mold is fixedly connected to an arc block; the bottom of the lower mold is fixedly connected to an arc protrusion; the upper end of the arc protrusion is fixedly connected to an insertion block; an air pipe is slidably connected in the slot; the end of the air pipe away from the arc protrusion is in sliding sealing contact with the arc block.

[0023] The beneficial effects of the present invention are as follows:

[0024] The present invention excavates a U-shaped groove at the bottom of the foundation trench, so that the user can easily put the prefabricated concrete pipe seat into the U-shaped groove; under the premise of ensuring that the center of the PCCP pipe is at a certain height from the ground, the excavation depth of the foundation trench is greatly reduced; on the one hand, the engineering volume per linear meter is: Figure 1 The excavation volume of the foundation pit reached 321.12m 3 , attached Figure 2 The excavation volume of the foundation pit reached 279.38m 3 , reducing the excavation and backfilling of foundation pit by 279.38m 3 On the other hand, the PCCP pipe C25 concrete pipe seat foundation is attached Figure 1 The excavation volume of the foundation pit reached 6.13m 3 , attached Figure 2 The excavation volume of the foundation pit reached 4.02m 3 , reducing the excavation and backfilling of foundation pit by 2.11m 3 ; and in terms of construction efficiency, each standard section was completed ahead of schedule. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention is further described below in conjunction with the accompanying drawings and implementation modes.

[0026] Figure 1 This is a construction cross-section diagram of a traditional PCCP pipeline;

[0027] Figure 2 It is a construction cross-sectional view of the PCCP pipeline of the present invention;

[0028] Figure 3 It is a process flow chart of the present invention;

[0029] Figure 4 It is a flow chart of the concrete pipe seat pouring method in the present invention;

[0030] Figure 5 It is a flow chart of the foundation trench excavation method in the present invention;

[0031] Figure 6 is a flow chart of the method for installing PCCP pipes in the present invention;

[0032] Figure 7 is a three-dimensional diagram of the mold used in the present invention;

[0033] Figure 8 yes Figure 7 The enlarged view of point A in the middle;

[0034] Fig. 9 It is a connection diagram of the PCCP pipe and the concrete pipe seat in the present invention;

[0035] Fig.10 yes Fig. 9 The enlarged view of point B in the middle;

[0036] Fig.11 is a perspective view of a flange used in the present invention;

[0037] In the figure: 1. mold; 11. lower mold; 111. arc-shaped protrusion; 112. plug block; 12. upper mold; 121. casting hole; 122. exhaust hole; 13. reserved hole; 131. round steel lifting ring; 14. arc-shaped block; 15. air pipe; 2. PCCP pipe; 21. flange; 22. arc-shaped cavity; 23. feed port; 24. air diffusion hole; 25. connecting pipe; 3. concrete pipe seat; 31. arc-shaped groove; 311. guide groove; 32. semicircular groove; 33. roller; 34. airway. DETAILED DESCRIPTION

[0038] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0039] like Figures 1 to 11 As shown, the construction process of a prestressed steel cylinder concrete pipe according to the present invention comprises the following steps:

[0040] S1: Prefabricating concrete pipe seat 3: Designing a casting mold 1 of the concrete pipe seat 3 according to the size of the prefabricated PCCP pipe 2, thereby manufacturing a concrete pipe seat 3 mold 1 with a support angle of 120° and a length of 300-500 mm; then casting the required concrete pipe seat 3 according to the mold 1 of the concrete pipe seat 3;

[0041] S2: Excavation of foundation trench: According to the slope ratio requirements (1:1.5 on the left, 1:2 on the right), the foundation trench is excavated in sections and layers, and the excavation depth of each layer does not exceed 3.0m. When the elevation is close to the elevation of the top surface of the U-shaped trench, the bottom of the foundation trench is leveled; after leveling, the U-shaped trench is positioned according to the size of the prefabricated concrete pipe seat 3, and excavation is carried out;

[0042] S3: Installation of concrete pipe seats 3: Prefabricated concrete pipe seats 3 need to be preliminarily inspected for appearance; concrete pipe seats 3 with serious honeycombs, pitting, damage, cracks, etc. shall not be used; and according to the PCCP pipe 2 standard 5m pipe, three prefabricated concrete pipe seats 3 are installed by crane for each section of pipe, located in the middle of the pipe and 250mm away from the edge of the pipe;

[0043] S4: Install PCCP pipe 2: Use two nylon belts of equal length to horizontally hang PCCP pipe 2; Hang PCCP pipe 2 to concrete pipe seat 3; Measure the elevation and position, and use medium-coarse sand to adjust the position and elevation of precast concrete pipe seat 3 for rough adjustment; and add thin steel pads to the contact surface between PCCP pipe 2 and concrete pipe seat 3 for fine adjustment to adjust the elevation position of PCCP pipe 2;

[0044] S5: Cast-in-place concrete pipe seat 3: After the PCCP pipe 2 is installed, concrete is poured between two adjacent precast concrete pipe seats 3 below each pipe section; thereby forming a cast-in-place concrete pipe seat 3 between two adjacent precast concrete pipe seats 3, with a length of 2000 to 3600 mm.

[0045] As an embodiment of the present invention, the method for pouring the concrete pipe seat 3 in S1 further includes:

[0046] S11: Since the mold 1 is divided into a lower mold 11 and an upper mold 12; and a pouring hole 121 and an exhaust hole 122 are opened at the upper end of the upper mold 12; a reserved hole 13 is opened in the middle of the pouring hole 121 and the exhaust hole 122; firstly, the lower mold 11 is placed on the vibrating table, and then the upper mold 12 is fixed to the upper end of the lower mold 11 by bolts; then, the concrete pouring pipe is inserted from the pouring hole 121; concrete is poured until the exhaust hole 122 overflows with concrete; and an Ω-shaped round steel ring 131 is installed in the reserved hole 13 in the middle of the two holes;

[0047] S12: After the installation of the round steel lifting ring 131 is completed; the vibrating table is turned on to vibrate the concrete, and the concrete is continuously added until the concrete is vibrated and compacted; the concrete in the mold 1 is left to stand for a period of time until the concrete solidifies and reaches 2.5MPa; the upper mold 12 is lifted by the round steel lifting ring 131; and the concrete in the lower mold 11 is cured for 14 days; when the concrete strength reaches 75% of the design strength, the lower mold 11 is removed;

[0048] As an embodiment of the present invention, the method of excavating the foundation trench in S2 is: before excavation, a temporary drainage ditch needs to be excavated on the left side of the slope, and during excavation, an excavator is used to excavate the left side of the top surface of the U-shaped trench to the bottom at a designed slope ratio of 1:1. When the excavation elevation is close to 15 cm from the base of the U-shaped trench, the earthwork is cleaned manually, and a water collection well is excavated at the end of the U-shaped trench to collect water in the U-shaped trench for easy discharge.

[0049] As an embodiment of the present invention, the method for installing the PCCP pipe 2 in S4 is: the PCCP pipe 2 is installed by the inner pulling method, a channel steel beam is fixed at the gap between the two installed pipes, a steel wire rope and a channel steel beam are used to fix the pipe to be installed, and a hand winch is used on the inside of the pipe to gradually tighten the pipe to be installed, so that the socket is connected to complete the pipe installation, and the construction process is gradually promoted;

[0050] In the conventional construction process of the existing PCCP pipe 2, the excavation width and depth of the foundation pit are often large; as the foundation pit is continuously excavated, the supporting capacity of the soil is continuously weakened, especially in the case of poor soil quality and high soil moisture, the slope will become more unstable, which will lead to collapse accidents, resulting in increased safety hazards; and as the foundation pit is dug deeper, not only the corresponding slope treatment, support structure and earthwork transportation engineering workload will increase, but also the construction time will be greatly extended, thereby reducing work efficiency; and as the foundation pit deepens, in order to ensure the stability and safety of the foundation pit, the foundation pit support structure needs to be strengthened, which leads to an increase in project investment;

[0051] During operation, the user needs to prefabricate the concrete pipe seat 3 before construction, and the prefabricated concrete pipe seat 3 is designed according to the size of the prefabricated D03600PCCP pipe 2, that is, the pipe thickness δ, the support angle of the concrete pipe seat 3 is 120° (the arc size is 30-50mm wider than the outer diameter of the PCCP pipe 2), the bottom and side wall thickness of the concrete pipe seat 3 is 2δ, the side wall slope ratio is 1:1, and the length range of the prefabricated concrete pipe seat 3 is 300-500mm; the arc size of the prefabricated pipe seat is wider than the PCCP pipe 2 outer diameter width 30 ~ 50mm; then according to the size of the concrete pipe seat 3 design required concrete pipe seat 3 mold 1; and the concrete pipe seat 3 mold 1 includes two parts: upper mold 12 and lower mold 11; that is, the user first places the lower mold 11 on the vibrating table; covers the upper mold 12 on the upper end of the lower mold 11; then introduces concrete from the pouring hole 121 at the end of the upper mold 12; until the exhaust hole 122 overflows the concrete; first install the round steel ring 131 between the pouring hole 121 and the exhaust hole 122 In the middle of the air hole 122, the bolt is inserted into the reserved hole 13 in the middle of the orifice of the air hole 122, and the bolt is fixed to the upper mold 12 through the reserved hole 13 on the orifice; the two sides of the round steel lifting ring 131 are inserted into the bolt to ensure that the round steel lifting ring 131 is tightly connected with the bolt; so that the round steel lifting ring 131 is installed in the middle position of the orifice of the air hole 122; similarly, another round steel lifting ring 131 is installed in the middle position of the orifice of the casting hole 121 by using a bolt; then the vibration platform is controlled to run; the reason why the round steel lifting ring 131 is installed before the vibration platform is operated in this application is that the installation of the round steel lifting ring 131 usually requires the reserved hole 13 in the mold 1 in advance, and the vibration and flow of concrete during the vibration process will cause the reserved hole 13 to be blocked or closed; so that the round steel lifting ring 131 will face the problem that the reserved hole 13 cannot be used after vibration; therefore, the round steel lifting ring 131 needs to be installed before the vibration platform is operated;

[0052] During the process of vibrating the concrete on the vibrating table, it is necessary to continuously add concrete to the pouring hole 121 until the concrete between the upper mold 12 and the lower mold 11 is vibrated and compacted; at this time, the concrete no longer emits bubbles, and the surface is flat and slurry-filled; at this time, the user removes the mold 1 with compacted concrete on the vibrating table and prepares to cure the concrete; before curing, the concrete needs to be left standing for a certain period of time to allow it to begin to solidify and harden; this standing time is usually called the initial solidification time or initial setting time; the initial setting time refers to the time point when the concrete begins to solidify and has a certain strength; that is, the initial After the setting time, the concrete needs to solidify and reach 2.5MPa; at this time, the round steel lifting ring 131 is lifted by a crane; so that the round steel lifting ring 131 can pull the upper mold 12 up and separate it from the lower mold 11, so that the upper end surface of the concrete in the lower mold 11 is exposed. At this time, the user sprinkles water on the concrete in the lower mold 11 for 14 days. When the concrete strength reaches 75% of the design strength, the prefabricated concrete pipe seat 3 is taken out from the lower mold 11; that is, by turning over the lower mold 11; the concrete pipe seat 3 in the lower mold 11 is poured out from the lower mold 11; and then the concrete pipe seat 3 is hoisted to the storage area;

[0053] During construction, the excavation of the foundation trench (to the top of the U-shaped trench): according to the slope ratio requirements (1:1.5 on the left, 1:2 on the right), the excavation is carried out in sections and layers, and the excavation depth of each layer does not exceed 3.0m, and the principle of "layered excavation and over-excavation is strictly prohibited" is strictly followed; when the excavation elevation is close to the elevation of the top of the U-shaped trench (10.18m), the trench is leveled and manually cleaned to prevent over-excavation; by leveling and manually cleaning the trench, the loose soil on the excavated slope can be removed in time to prevent earth collapse and reduce the danger to excavation machinery and workers; and the 15cm earth on the top of the U-shaped trench is cleaned manually and then taken away by the excavator; after the earthwork is excavated When digging to the top of the U-shaped trough, the U-shaped trough is positioned and laid out according to the size of the prefabricated pipe seat to determine the excavation range; since the cross-sectional size of the U-shaped trough is small and the excavation depth does not exceed 3.0m, an excavator is used to dig to the bottom at the left side of the top of the U-shaped trough according to the designed slope ratio of 1:1. When the elevation is close to 15cm of the U-shaped trough base, the earthwork is cleaned manually; and a temporary drainage ditch is set on the left side of the slope to prevent water from flowing into the U-shaped trough. A water collection well is set at the end of the U-shaped trough to collect the water in the U-shaped trough and discharge it into the water collection well; by setting up drainage ditches and water collection wells, the moisture content of the base soil can be reduced, and the influence of liquid water and saturated water pressure can be reduced, thereby improving the stability of the foundation trench;

[0054] When the foundation trench excavation is completed, the prefabricated concrete pipe seat 3 is transported to the construction site; the appearance quality of the concrete pipe seat 3 is tested, and the concrete pipe seat 3 with honeycomb, pockmarks, damage, cracks and other problems on the surface shall not be used; the concrete pipe seat 3 is then hoisted into the U-shaped groove; and according to the PCCP pipe 2 standard 5m pipe, three prefabricated pipe seats are installed on each section of the pipe by a crane, and the position is in the middle of the pipe and 250mm away from the edge of the pipe; when the concrete pipe seat 3 is installed, the required PCCP pipe 2 is cleaned inside to remove any debris, and the pipe material and the socket and spigot are checked one by one for damage; if damaged If the pipe is damaged, the damaged part should be repaired before use; the PCCP pipe 2 used in this process has an inner diameter of 3.6m, a single-section pipe length of 5m, and a maximum weight of about 42t~70t, so it is hoisted horizontally; two nylon belts of equal length are generally used for hoisting during on-site installation; the distance between the two nylon belts is 2 / 3 of the pipe length, that is, 3.33m. It is strictly forbidden to use wire ropes to directly hoist pipes, and it is strictly forbidden to hoist pipes through the heart; handle with care during hoisting, and collision is strictly prohibited; after the PCCP pipe 2 is lowered to the top of the concrete pipe seat 3, the elevation and position are measured, and the rough adjustment is made by using medium and coarse sand Adjust the position and elevation of the precast concrete pipe seat 3, and fine-tune the PCCP pipe 2 by adding a thin steel pad on the contact surface between the concrete pipe seat 3 to adjust the elevation of the PCCP pipe 2; PCCP pipe 2 is installed using the inner pulling method, and the channel steel beam is fixed to the gap between the two installed pipe sections, and the pipe to be installed is fixed with a wire rope and the channel steel beam. The pipe to be installed is gradually tightened by a hand hoist on the inside of the pipe to achieve the butt joint of the socket and complete the pipe installation, and the construction process is gradually promoted; after the PCCP pipe 2 is installed, the adjacent pipes under each pipe section Concrete is poured between two precast concrete pipe seats 3; thus, a cast-in-place concrete pipe seat 3 is formed between two adjacent precast concrete pipe seats 3, and its length is 2000-3600 mm; since the lever hoist is a simple and portable tool, it is more convenient and flexible to use than other large equipment or machinery, and is suitable for installation in a small space or limited working area; and the operator can use the lever hoist to adjust the force according to the actual situation and needs, avoid excessive force or sudden stress, thereby reducing the risk of personal injury and protecting the integrity of the pipeline;

[0055] The present invention excavates a U-shaped groove at the bottom of the foundation trench, so that the user can easily put the prefabricated concrete pipe seat 3 into the U-shaped groove; under the premise of ensuring that the center of the PCCP pipe 2 is at a certain height from the ground, the excavation depth of the foundation trench is greatly reduced; on the one hand, the engineering volume per linear meter is: Figure 1 The excavation volume of the foundation pit reached 321.12m 3 , attached Figure 2 The excavation volume of the foundation pit reached 279.38m 3 , reducing the excavation and backfilling of foundation pit by 279.38m 3 On the other hand, PCCP pipe 2C25 concrete pipe seat 3 foundation attachment Figure 1 The excavation volume of the foundation pit reached 6.13m3 , attached Figure 2 The excavation volume of the foundation pit reached 4.02m 3 , reducing the excavation and backfilling of foundation pit by 2.11m 3 ; Moreover, in terms of construction efficiency, each standard section was completed ahead of schedule;

[0056] As an implementation mode of the present invention, an arc groove 31 is formed on the upper end of the concrete pipe seat 3; and a flange 21 is fixedly connected to the outer wall of the PCCP pipe 2.

[0057] As an implementation mode of the present invention, a semicircular groove 32 is formed at the lower end of the concrete pipe seat 3; a roller 33 is rotatably connected in the semicircular groove 32; and the roller 33 is formed by pouring concrete.

[0058] As an embodiment of the present invention, the flange 21 is made of high carbon steel material; the cross-sectional shape of the flange 21 is set to be a "J" shape; an arc-shaped cavity 22 is opened inside the flange 21; a feed port 23 connected to the arc-shaped cavity 22 is opened outside the flange 21; and an air diffusion hole 24 is opened at the upper end of the flange 21.

[0059] As an embodiment of the present invention, connecting pipes 25 are installed on both sides of the flange 21; the connecting pipes 25 are connected to the arc-shaped cavity 22 in the flange 21; an air duct 34 is opened inside the concrete pipe seat 3; one end of the air duct 34 is connected to the semicircular groove 32; and the other end is connected to the arc-shaped groove 31.

[0060] As an embodiment of the present invention, guide grooves 311 communicating with the air passage 34 are provided on both sides of the arc-shaped groove 31 ; the guide grooves 311 are in the shape of a frustum.

[0061] As an embodiment of the present invention, the lower end of the upper mold 12 is fixedly connected to an arc block 14; the bottom of the lower mold 11 is fixedly connected to an arc protrusion 111; the upper end of the arc protrusion 111 is fixedly connected to an insert block 112; an air pipe 15 is slidably connected in the slot; one end of the air pipe 15 away from the arc protrusion 111 is in sliding sealing contact with the arc block 14;

[0062] During operation, when two adjacent PCCP pipes 2 are pulled together by the inner pulling method, the PCCP pipe 2 will slide in contact with the concrete pipe seat 3. The sliding contact will cause friction between the pipe and the concrete pipe seat 3. If the friction is too large or uneven, the pushing resistance will increase, which will directly lead to the difficulty of pushing the PCCP pipe 2. It may even cause damage to the PCCP pipe 2. Therefore, the present application provides a semicircular groove 32 at the lower end of the concrete pipe seat 3, an arc groove 31 is provided above the concrete pipe seat 3, and a flange 21 is provided on the outer wall of the PCCP pipe 2. When placing the concrete pipe seat 3 into the U-shaped groove, first push it inward. A roller 33 made of prefabricated concrete material is placed in the U-shaped groove; and when the concrete pipe seat 3 is placed in the U-shaped groove, the semicircular groove 32 at the lower end of the concrete pipe seat 3 is aligned with the roller 33; so that when the concrete pipe seat 3 is placed in the U-shaped groove, the roller 33 first placed in the U-shaped groove can be stuck in the semicircular groove 32 below the concrete pipe seat 3; since at least two semicircular grooves 32 are provided below each concrete pipe seat 3, at least two rollers 33 are provided below each concrete pipe seat 3; then the PCCP pipe 2 is hoisted, even if the air diffusion holes 24 on the flange 21 on the surface of the PCCP pipe 2 face upward, ; At this time, the connecting pipe 25 is located directly below; when placing the PCCP pipe 2, three concrete pipe seats 3 are provided below one PCCP pipe 2; therefore, three flanges 21 are provided on the surface of the PCCP pipe 2; therefore, the user uses a tool to push the three concrete pipe seats 3 in the U-shaped groove to slide in the U-shaped groove; since the concrete pipe seats 3 are in rolling contact with the U-shaped groove through the roller 33; the friction between the concrete pipe seats 3 and the bottom of the U-shaped groove is small; it is convenient for the user to push the concrete pipe seats 3 to slide in the U-shaped groove; until the three concrete pipe seats 3 drive the upper arc grooves 31 to be located below the three flanges 21 of the PCCP pipe 2; at this time, the PCCP pipe 2 is placed in the U-shaped groove. The CCP pipe 2 is put down, so that the flange 21 on the surface of the PCCP pipe 2 can be inserted into the arc groove 31. Therefore, when the inner pulling method is used to pull two adjacent PCCP pipes 2 for connection, the PCCP pipe 2 can push the lower concrete pipe seat 3 to slide synchronously in the U-shaped groove through the flange 21, avoiding sliding contact between the PCCP pipe 2 and the concrete pipe seat 3, preventing the surface of the PCCP pipe 2 from being damaged by friction, improving the surface quality of the PCCP pipe 2, and also reducing the difficulty of connecting the PCCP pipes 2 by the inner pulling method, speeding up the connection speed between the PCCP pipes 2, thereby improving work efficiency.

[0063] During the hanging process of the PCCP pipe 2, the PCCP pipe 2 is not directly opposite to the concrete pipe seat 3, that is, the PCCP pipe 2 will have a certain left and right offset relative to the concrete pipe seat 3, so the connecting pipes 25 on both sides of the flange 21 are not directly above the airway 34. Therefore, by setting guide grooves 311 on both sides of the arc groove 31, and setting the guide grooves 311 to be frustum-shaped, and the length of the end of the guide groove 311 away from the airway 34 is longer, so that during the placement of the PCCP pipe 2, the PCCP pipe 2 drives the protrusion to enter the arc groove 31 of the concrete pipe seat 3, so that the protrusion drives the connecting pipes 25 on both sides to enter the guide groove 311, and as the PCCP pipe 2 The connecting pipe 25 is continuously placed downward; the PCCP pipe 2 drives the connecting pipe 25 to contact the inclined surface of the guide groove 311 below, so that the connecting pipe 25 can slide downward along the inclined surface of the guide groove 311; at this time, the guide groove 311 generates a driving force on the connecting pipe 25 through the side wall of the inclined surface, and drives the connecting pipe 25 to drive the entire PCCP pipe 2 to deviate to the other side; until the connecting pipe 25 slides to the bottom of the guide groove 311; at this time, the connecting pipe 25 is directly opposite to the airway 34, and the connecting pipe 25 is in close contact with the port of the airway 34; and the PCCP pipe 2 is also directly opposite to the concrete pipe seat 3 up and down; avoid the misalignment between the PCCP pipe 2 and the concrete pipe seat 3, and ensure the connection between the connecting pipe 25 and the airway 34;

[0064] After the PCCP pipe 2 is connected by the inner pulling method, the user fills the flange 21 with concrete through the feed port 23; the concrete enters the airway 34 through the connecting pipe 25; the concrete entering the airway 34 flows out from the semicircular groove 32; the concrete flowing into the semicircular groove 32 can be filled between the semicircular groove 32 and the roller 33, until the space between the semicircular groove 32 and the roller 33 is filled with concrete, and the concrete cannot be discharged through the airway 34; at this time, the concrete is continuously filled and filled into the arc cavity 22 of the flange 21; because the air diffusion hole 24 at the upper end of the flange 21 is connected with the arc cavity 22; during the process of concrete filling the arc cavity 22, the gas in the arc cavity 22 The concrete is squeezed out from the air diffusion hole 24; by injecting concrete into the semicircular groove 32; so that the concrete filled between the semicircular groove 32 and the roller 33 can fix the roller 33 and the concrete pipe seat 3, and the concrete filled in the semicircular groove 32 can support the bottom of the semicircular groove 32 after solidification; thereby effectively strengthening the structural strength of the concrete pipe seat 3; improving the bearing capacity of the concrete pipe seat 3; and then in the subsequent foundation trench burial process; the buried soil covers the PCCP pipe 2, thereby increasing the gravity exerted by the PCCP pipe 2 on the concrete pipe seat 3; thereby strengthening the structural strength of the concrete pipe seat 3; and can greatly improve the use effect and service life of the concrete pipe seat 3;

[0065] Since the PCCP pipe 2 refers to a water pipe made by winding annular prestressed steel wire on a high-strength concrete pipe core with a steel cylinder and then spraying a dense cement mortar protective layer thereon, the installation of the "J"-shaped flange 21 is before the prestressed steel wire is wound; first, the "J"-shaped flange 21 is sleeved on the high-strength concrete pipe core with a steel cylinder, and then the prestressed steel wire is used to tightly wind the "J"-shaped flange 21 on the high-strength concrete pipe core with a steel cylinder; finally, the contact portion of the prestressed steel wire and the flange 21 with the high-strength concrete pipe core is wrapped with a cement mortar protective layer; and the flange 21 is made of high-carbon steel material, so that the flange 21 has high strength and hardness, which not only enables the flange 21 to improve the structural strength of the PCCP pipe 2; The flange 21 will not bend during the process of pushing the concrete pipe seat 3; and when the flange 21 is placed, the high carbon steel flange 21 has a strong supporting effect on the PCCP pipe 2, ensuring the service life of the flange 21; and an arc groove 31 is provided in the flange 21, and the arc surface of the arc groove 31 is close to the outer surface of the flange 21; when the PCCP pipe 2 is placed, the lower end of the flange 21 is affected by the ground blocking force; the blocking force is transmitted to the arc surface of the arc groove 31 through the flange 21, because the stress distribution of the arc surface is more uniform than other shapes; therefore, when the flange 21 is subjected to internal pressure, its circumferential force is evenly distributed, so that the flange 21 can better withstand the pressure of the PCCP pipe 2 and reduce the risk of deformation and instability;

[0066] When the concrete pipe seat 3 is constructed, since the lower end of the upper mold 12 of the concrete pipe seat 3 mold 1 is fixedly connected with an arc block 14; and the bottom of the lower mold 11 is fixedly connected with an arc protrusion 111; and the upper end of the arc protrusion 111 is fixedly connected with an insert block 112; one end of the air pipe 15 is sleeved on the insert block 112; the air pipe 15 is made of high carbon steel material; then the upper mold 12 is placed on the upper end surface of the lower mold 11; at this time, the arc protrusion 111 on the surface of the upper mold 12 is in sliding and sealing contact with the end of the air pipe 15 away from the slot, as the concrete is injected through the pouring hole 121, the concrete entering between the upper mold 12 and the lower mold 11 can wrap the air pipe 15; when the concrete solidifies, the air pipe 15 becomes the airway 34 inside the concrete pipe seat 3; at the same time, because the air pipe 15 is made of high carbon steel material, the air pipe 15 made of high carbon steel plays the role of reinforcing ribs in the concrete pipe seat 3; thereby, the structural strength of the concrete pipe seat 3 is also improved; so that the practicality of the present invention is improved.

[0067] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the attached Figure 1The orientation or positional relationship shown is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as limiting the scope of protection of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0068] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A prestressed steel cylinder concrete pipe construction process, characterized in that: The following steps are involved: S1: Prefabricating a concrete pipe seat (3): designing a casting mold (1) of the concrete pipe seat (3) according to the size of the prefabricated PCCP pipe (2), thereby manufacturing a concrete pipe seat (3) mold (1) with a support angle of 120° and a length of 300 to 500 mm; then, casting the required concrete pipe seat (3) according to the mold (1) of the concrete pipe seat (3); S2: Excavation of foundation trench: According to the slope ratio requirement, the left side is 1:1.5, and the right side is 1:

2. The foundation trench is excavated in sections and layers, and the excavation depth of each layer does not exceed 3.0m. When the excavation elevation is close to the elevation of the top surface of the U-shaped trench, the bottom of the foundation trench is leveled. After leveling, the U-shaped trench is positioned according to the size of the prefabricated concrete pipe seat (3), and excavation is carried out. S3: Installing concrete pipe seats (3): Prefabricated concrete pipe seats (3) need to be preliminarily inspected for appearance; concrete pipe seats (3) with serious honeycomb, rough surface, damage, or cracks shall not be used; and according to the PCCP pipe (2) standard 5m pipe, three prefabricated concrete pipe seats (3) are installed by crane for each section of pipe, located in the middle of the pipe and 250mm from the edge of the pipe; S4: Installing the PCCP pipe (2): Using two nylon straps of equal length to horizontally hang the PCCP pipe (2); After the PCCP pipe (2) is hung and placed on the concrete pipe seat (3); measuring the elevation and position; roughly adjusting the position and elevation of the precast concrete pipe seat (3) by using medium-coarse sand; fine-adjusting by adding a thin steel pad to the contact surface between the PCCP pipe (2) and the concrete pipe seat (3) to adjust the elevation position of the PCCP pipe (2); S5: Cast-in-place concrete pipe seat (3): After the PCCP pipe (2) is installed, concrete is poured between two adjacent precast concrete pipe seats (3) below each pipe section; thereby forming a cast-in-place concrete pipe seat (3) between the two adjacent precast concrete pipe seats (3), the length of which is 2000-3600 mm; The method for pouring the concrete pipe seat (3) in S1 further comprises: S11: Since the mold (1) is divided into a lower mold (11) and an upper mold (12); and the upper end of the upper mold (12) is provided with a pouring hole (121) and an exhaust hole (122); and a reserved hole (13) is provided in the middle of the pouring hole (121) and the exhaust hole (122); firstly, the lower mold (11) is placed on a vibrating table, and then the upper mold (12) is fixed to the upper end of the lower mold (11) by bolts; then, a concrete pouring pipe is inserted from the pouring hole (121); concrete is poured until concrete overflows from the exhaust hole (122); and an Ω-shaped round steel hanging ring (131) is installed in the reserved hole (13) in the middle of the two holes; S12: After the installation of the round steel lifting ring (131) is completed; the vibrating table is turned on to vibrate the concrete, and concrete is continuously added until the concrete is vibrated and compacted; the concrete in the mold (1) is left to stand for a period of time until the concrete solidifies and reaches 2.5 MPa; the upper mold (12) is lifted by the round steel lifting ring (131); and the concrete in the lower mold (11) is cured for 14 days; when the concrete strength reaches 75% of the design strength, the lower mold (11) is removed; The method of excavating the foundation trench in S2 is: before excavation, a temporary drainage ditch needs to be excavated on the left side of the slope. During excavation, an excavator is used to excavate the left side of the top surface of the U-shaped trench to the bottom at a designed slope ratio of 1:

1. When the elevation is close to 15cm of the base of the U-shaped trench, the earthwork is cleaned manually, and a water collection well is dug at the end of the U-shaped trench to collect the water in the U-shaped trench into the water collection well for easy discharge; The method for installing the PCCP pipe (2) in S4 is as follows: the PCCP pipe (2) is installed by the inner pulling method, a channel steel beam is fixed to the gap between the sockets of two installed pipe sections, a steel wire rope and the channel steel beam are used to fix the pipe to be installed, and a hand winch is used on the inner side of the pipe to gradually tighten the pipe to be installed, so that the sockets are connected and the pipe installation is completed, and the construction process is gradually promoted.

2. A prestressed steel cylinder concrete pipe construction process according to claim 1, characterized in that: An arc-shaped groove (31) is formed at the upper end of the concrete pipe seat (3); and a flange (21) is fixedly connected to the outer wall of the PCCP pipe (2).

3. A prestressed steel cylinder concrete pipe construction process according to claim 2, characterized in that: A semicircular groove (32) is provided at the lower end of the concrete pipe seat (3); a rotating roller (33) is rotatably connected in the semicircular groove (32); and the rotating roller (33) is formed by pouring concrete.

4. A prestressed steel cylinder concrete pipe construction process according to claim 3, characterized in that: The flange (21) is made of high carbon steel material; the cross-sectional shape of the flange (21) is set to be a "J" shape; an arc-shaped cavity (22) is provided inside the flange (21); a feed port (23) connected to the arc-shaped cavity (22) is provided outside the flange (21); and a gas diffusion hole (24) is provided at the upper end of the flange (21).

5. A prestressed steel cylinder concrete pipe construction process according to claim 4, characterized in that: Connecting pipes (25) are installed on both sides of the flange (21); the connecting pipes (25) are connected to the arc-shaped cavity (22) in the flange (21); an air passage (34) is opened inside the concrete pipe seat (3); one end of the air passage (34) is connected to the semicircular groove (32); and the other end is connected to the arc-shaped groove (31).

6. A prestressed steel cylinder concrete pipe construction process according to claim 5, characterized in that: Guide grooves (311) communicating with the airway (34) are provided on both sides of the arc-shaped groove (31); the guide grooves (311) are in the shape of a frustum.

7. The construction process of a prestressed steel cylinder concrete pipe according to claim 5, characterized in that: The lower end of the upper die (12) is fixedly connected to an arc-shaped block (14); the bottom of the lower die (11) is fixedly connected to an arc-shaped protrusion (111); and the upper end of the arc-shaped protrusion (111) is fixedly connected to an insert block (112).

Images