The hoisting structure of the new pipe-wrapped well for the existing pipeline and the construction method of the new pipe-wrapped well

Abstract

The present invention discloses a hoisting structure for a newly built pipe-wrapped well for an existing pipeline and a construction method for a newly built pipe-wrapped well, including a plurality of steel beams arranged below the existing pipeline for carrying the existing pipeline, and steel wire ropes arranged on both sides of the existing pipeline for suspending the steel beams; a plurality of limiting pads are arranged on the bearing surface of the steel beam facing the existing pipeline, and a steel bar anchoring groove is arranged on the side of the steel beam. During construction, firstly, the foundation pit is excavated to 0.25D below the center line of the existing pipeline, the steel beam is placed below the existing pipeline and the limiting pad is installed, and the steel wire rope is arranged to connect with the upper steel frame; then the bottom plate below the existing pipeline is completed, and the steel bars of the bottom plate parallel to the existing pipeline are fixed to the steel beam through the steel bar anchoring groove, and then the subsequent construction of the newly built pipe-wrapped well is completed. The present invention effectively reduces the excavation depth of the foundation pit, reduces the construction risk, and reduces the amount of plain concrete; at the same time, it saves construction time and reduces the time of impact on municipal roads during construction.

Description

Technical Field

[0001] The invention relates to the technical field of pipe-wrapped well construction, and in particular to a hoisting structure for building a new pipe-wrapped well on an existing pipeline and a construction method for the new pipe-wrapped well. Background Art

[0002] The drainage system is an important urban infrastructure and the lifeblood of the city. In recent years, with the acceleration of urbanization, the amount of urban sewage discharged has increased. The sewage pipes in many cities have been operating under pressure for a long time, and there are serious sewage overflow pollution and frequent floods. These problems highlight that the drainage pipes in most cities in my country can no longer meet the needs of urban development, and the reconstruction, expansion and new construction of drainage systems are imminent.

[0003] Due to the large number of facilities and pipelines in some existing pumping stations and limited space, it is impossible to renovate or build new interception wells in the pumping stations. The only way to achieve the goal of intercepting rainwater and sewage is to carry out interception renovation on the existing main pipes. How to carry out safe and efficient interception renovation without interrupting the operation of the existing drainage pipelines, reduce construction risks, shorten the construction period, and reduce the impact on the existing roads is an urgent problem to be solved in the new interception well project.

[0004] Current status of related technologies in this field:

[0005] At present, the construction method of pipe well is mainly open excavation. The specific steps are as follows:

[0006] 1) Level the construction site, construct retaining piles and water-blocking curtains, and reinforce the foundation pit;

[0007] 2) Construct the top ring beam and the first support. After the support and top ring beam reach the designed strength, excavate the earth layer by layer to the area 0.5m above the pipeline;

[0008] 3) Continue to dig downwards by manual excavation and expose the scope of the pipe section until the excavation reaches 0.25D below the centerline of the pipeline, where D is the outer diameter of the existing pipeline;

[0009] 4) Locally excavate the soil under the pipeline, break the cushion layer under the original pipeline, and then place the integrated steel beam for suspension protection and permanent load bearing under the pipeline, install the steel wire rope and connect it to the upper steel frame to ensure that the steel beam effectively supports the existing pipeline through the limit pad;

[0010] 5) Continue to excavate the soil downward to the designed elevation of the pit bottom (including the height of the steel beam, the thickness of the bottom plate and the thickness of the cushion layer), and construct the cushion layer and the bottom plate waterproof layer;

[0011] 6) Tie the bottom plate steel bars, pour the bottom plate concrete, and pour the plain concrete base below the center line of the pipeline;

[0012] 7) After the plain concrete foundation under the bottom plate and pipeline reaches the design strength, remove the wire rope and steel frame;

[0013] 8) Continue to construct the side walls and top plate of the well upwards, and treat the joints between the pipes and the side walls. Then cut off the pipes in the well to achieve the purpose of interception.

[0014] The above-mentioned existing technical solutions need to consider the space occupied by the steel sections, which will lead to an increase in excavation depth, an increase in excavation work volume, and a longer construction period. In addition, there is no enclosure structure directly below the pipeline, and the increase in excavation depth will also lead to an increase in construction risks.

[0015] In addition, if it is necessary to ensure the normal operation of the pipeline before the construction of the intercepting well is completed, it is necessary to pour a plain concrete base under the pipeline, which increases the amount of plain concrete poured.

[0016] Therefore, how to effectively reduce the excavation depth of the foundation pit and the amount of subsequent concrete pouring, shorten the project construction period, and reduce construction risks has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0017] In view of the above-mentioned defects of the existing technology, the present invention provides a hoisting structure for a newly built pipe-wrapped well for the existing pipeline and a construction method for a newly built pipe-wrapped well, the purpose of which is to effectively reduce the excavation depth of the foundation pit, reduce the construction risk, and reduce the amount of plain concrete; at the same time, save construction time and reduce the impact time on municipal roads during construction.

[0018] To achieve the above-mentioned purpose, the present invention discloses a hoisting structure for a newly built pipe-wrapped well for an existing pipeline, comprising a plurality of steel beams arranged below the existing pipeline for supporting the existing pipeline, and steel wire ropes arranged on both sides of the existing pipeline for suspending the steel beams.

[0019] Wherein, each of the steel beams includes a bearing surface on the upper side facing the existing pipeline;

[0020] Three limiting pads are provided on each of the bearing surfaces corresponding to the arc-shaped outer side wall below the existing pipeline;

[0021] The three limiting pads include a limiting pad A located directly below the center of the existing pipeline, and limiting pads B symmetrically arranged on both sides directly below the center of the existing pipeline;

[0022] A steel bar anchoring groove is provided on the side of each of the steel beams;

[0023] Each of the steel bar anchoring grooves is used to anchor the steel bars in the bottom plate parallel to the existing pipeline when constructing the bottom plate below the existing pipeline.

[0024] Preferably, each of the steel beams is provided with a lifting ring at a position corresponding to the connection of the corresponding steel wire rope, and is connected to the corresponding steel wire rope through the lifting ring.

[0025] Preferably, each of the A limiting pads has a height of h1, a width of b1, and a length of w1;

[0026] The height of each B limit pad close to the inner side of the center of the existing pipeline is h 21 , the height away from the center of the existing pipeline is h 22 , the width is the same as that of the corresponding A limit pad, both are b1;

[0027] The distance from the center position of each B limit pad to the center of the existing pipeline, that is, the distance from the center position of each B limit pad to the center position of the corresponding A limit pad is d1;

[0028] The outer diameter of the existing pipeline is D;

[0029]

[0030] b1,b2≥max{(0.02D+2×h1),(0.02D+0.04D)};

[0031] in,

[0032] Each of the A limit pads and each of the B limit pads shall meet the compressive bearing capacity requirements:

[0033] F L ≤1.35β L f c A L ;

[0034]

[0035] A L =0.02Dw1;

[0036] Ab=min{(0.02D+2×h1)×w1, (0.02D+0.04D)×w1};

[0037] Among them, F L The weight of the pipeline borne by the steel beam; f c is the design value of the compressive strength of concrete; w1 is the length of the limit pad.

[0038] Preferably, each of the steel beams is an I-beam.

[0039] Preferably, the length of each of the steel bar anchor grooves is L s, the outer diameter of the existing pipeline is D;

[0040]

[0041] N=nf y A s ;

[0042] Where σ is the tensile stress at the weld between the anchor groove and the steel web, L W h is the length of the welding seam between the anchor groove and the steel web; e is the calculated thickness of the weld connecting the anchor groove and the steel section, is the strength design value of the fillet weld, n is the number of steel bars in the anchor groove, and f y is the tensile strength of the steel bars in the anchor groove, A s is the cross-sectional area of ​​the steel bars in the anchor groove.

[0043] The present invention also provides a construction method for a newly built pipe-wrapped well in a hoisting structure for a newly built pipe-wrapped well of an existing pipeline, comprising the following steps:

[0044] Step 1: Level the construction site, construct retaining piles and water-blocking curtains on both sides of the existing pipeline, and reinforce the foundation pit;

[0045] Step 2: construct the top ring beam and the first support of the foundation pit, and after the top ring beam and the first support reach the designed strength, excavate the earth in layers to the area 0.5m above the existing pipeline;

[0046] Step 3, continue to dig downwards by manual excavation to reveal the scope of the existing pipeline, and dig to 0.25D below the center line of the existing pipeline, where D is the outer diameter of the existing pipeline;

[0047] Step 4: excavate the soil below the existing pipeline locally, break the cushion layer under the existing pipeline, then place the steel beam under the existing pipeline and install the limit pad, and then set the steel wire rope to connect with the upper steel frame to ensure that the steel beam can effectively support the existing pipeline through the limit pad;

[0048] Step 5: Continue to excavate the soil downward to the designed elevation of the bottom of the foundation pit, including the thickness of the bottom plate and the cushion layer, and construct the cushion layer and bottom plate waterproof layer of the foundation pit;

[0049] Step 6, tying the bottom plate steel bars, wherein among the steel bars of the bottom plate located below the existing pipeline, the steel bars parallel to the existing pipeline are fixed to the steel beam through the steel bar anchoring groove, and the gap in the steel bar anchoring groove is filled with self-compacting concrete, and then the concrete of the bottom plate is poured;

[0050] Step 7: After the bottom plate strength reaches the design requirements, remove the steel wire rope and the corresponding upper steel frame, and then pour the side wall of the newly built pipe well upwards;

[0051] Step 8: At the connection between the wall of the newly built pipe-wrapped well and the existing pipeline, cut off the pipeline in the newly built pipe-wrapped well, then remove the abandoned pipe sections cut off in the newly built pipe-wrapped well to achieve flow interception; then chisel out the top ring beam and the first support of the foundation pit, construct the top plate and top plate waterproof layer of the newly built pipe-wrapped well, and then backfill and cover with soil.

[0052] Beneficial effects of the present invention:

[0053] This technology combines the pipeline suspension protection steel beam and the pipeline bottom plate hidden beam into one, sets a limit pad on the upper flange of the steel beam and also serves as a protective layer pad for the bottom plate steel beam; the anchor connection of the longitudinal steel bars under the pipeline is achieved through the steel bar anchor groove on the web of the steel beam; it can effectively reduce the excavation depth of the foundation pit, reduce construction risks, and reduce the amount of plain concrete; at the same time, it saves construction time and reduces the impact time on municipal roads during construction.

[0054] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 A schematic structural diagram of an embodiment of the present invention is shown.

[0056] Figure 2 A three-dimensional structural schematic diagram of an embodiment of the present invention is shown.

[0057] Figure 3 A partial enlarged structural schematic diagram of the contact portion between the existing pipeline and the limiting pad in one embodiment of the present invention is shown.

[0058] Figure 4 A schematic diagram of the cross-sectional structure of the bottom plate below the existing pipeline after completion in one embodiment of the present invention is shown.

[0059] Figure 5 A schematic diagram of the perspective structure of the top view of the contact portion between the existing pipeline and the limiting pad in one embodiment of the present invention is shown.

[0060] Figure 6 A schematic diagram of the longitudinal cross-sectional structure of an existing pipeline in a suspended state in one embodiment of the present invention is shown.

[0061] Figure 7 A schematic diagram of the outer side structure of the bottom plate below the existing pipeline after completion in one embodiment of the present invention is shown.

[0062] Figure 8A schematic diagram of the longitudinal cross-sectional structure of the bottom plate below the existing pipeline after completion in one embodiment of the present invention is shown.

[0063] Fig. 9 A schematic diagram of the structure of a bottom plate and a limiting pad under an existing pipeline in an embodiment of the present invention is shown.

[0064] Fig.10 A schematic diagram showing a state in which construction step 1 is completed according to an embodiment of the present invention.

[0065] Fig.11 A schematic diagram showing a state in which construction step 2 is completed according to an embodiment of the present invention.

[0066] Fig.12 A schematic diagram showing a state in which construction step 3 is completed according to an embodiment of the present invention.

[0067] Fig.13 A schematic diagram showing a state in which construction step 4 is completed according to an embodiment of the present invention.

[0068] Fig.14 A schematic diagram showing a state in which construction step 5 is completed according to an embodiment of the present invention.

[0069] Fig.15 A schematic diagram showing a state in which construction step 6 is completed according to an embodiment of the present invention.

[0070] Fig.16 A schematic diagram showing a state in which construction step 7 is completed according to an embodiment of the present invention.

[0071] Fig.17 A schematic diagram showing a state in which construction step 8 is completed according to an embodiment of the present invention. DETAILED DESCRIPTION

[0072] Example

[0073] like Figures 1 to 9 As shown, the hoisting structure of the newly built pipe-wrapped well for the existing pipeline includes a number of steel beams arranged below the existing pipeline for supporting the existing pipeline, and steel wire ropes arranged on both sides of the existing pipeline for suspending the steel beams.

[0074] Wherein, each steel beam includes a bearing surface on the upper side facing the existing pipeline;

[0075] Three limit pads are provided on each bearing surface corresponding to the arc-shaped outer side wall under the existing pipeline;

[0076] The three limit pads include a limit pad A located directly below the center of the existing pipeline, and a limit pad B symmetrically arranged on both sides directly below the center of the existing pipeline;

[0077] Each steel beam is provided with a steel bar anchor groove on its side;

[0078] Each steel bar anchoring groove is used to anchor the steel bars in the bottom plate parallel to the existing pipeline when constructing the bottom plate under the existing pipeline.

[0079] Preferably, each steel beam is provided with a lifting ring at a position corresponding to the connection of the corresponding steel wire rope, and is connected to the corresponding steel wire rope through the lifting ring.

[0080] The principle of the present invention is as follows:

[0081] By utilizing pipeline suspension protection and permanent load-bearing steel beams, the steel beams are used as pipeline suspension protection devices during the foundation pit construction phase and as part of the permanent load-bearing components of the bottom plate during the use phase, which can effectively reduce the excavation depth of the foundation pit and the amount of concrete pouring in the later stage; an integrated pipeline limit pad is set on the upper flange of the steel beam, which also serves as a protective layer pad for the bottom plate steel beam, and the pad is connected to the upper flange of the steel beam through bolts; in addition, steel bar anchor grooves are set on both sides of the web of the steel beam, which can realize quick connection with steel bars with end anchor plates, effectively solving the problems of insufficient space for punching and welding operations between the steel bars and the steel web under the pipeline, thereby shortening the project construction period, reducing construction risks, and having good social and economic benefits.

[0082] In some embodiments, each A-limiting pad has a height of h1, a width of b1, and a length of w1;

[0083] The height of each B limit pad close to the inner side of the existing pipeline center is h 21 , the height of the outer side away from the center of the existing pipeline is h 22 , the width is the same as the corresponding A limit pad, both are b1;

[0084] The distance from the center of each B limit pad to the center of the existing pipeline, that is, the distance from the center of each B limit pad to the center of the corresponding A limit pad is d1;

[0085] The outer diameter of the existing pipeline is D;

[0086]

[0087] b1,b2≥max{(0.02D+2×h1),(0.02D+0.04D)};

[0088] in,

[0089] Each A limit pad and each B limit pad shall meet the compressive bearing capacity requirements:

[0090] F L ≤1.35β L f c A L ;

[0091]

[0092] A L =0.02Dw1;

[0093] Ab=min{(0.02D+2×h1)×w1, (0.02D+0.04D)×w1};

[0094] Among them, F L The weight of the pipeline borne by the steel beam; f c is the design value of the compressive strength of concrete; w1 is the length of the limit pad.

[0095] In some embodiments, each steel beam is an I-beam.

[0096] In some embodiments, the length of each steel bar anchor groove is L s , the outer diameter of the existing pipeline is D;

[0097]

[0098] N=nf y A s ;

[0099] Where σ is the tensile stress at the weld between the anchor groove and the steel web, L W h is the length of the welding seam between the anchor groove and the steel web; e is the calculated thickness of the weld connecting the anchor groove and the steel section, is the strength design value of the fillet weld, n is the number of steel bars in the anchor groove, and f y is the tensile strength of the steel bars in the anchor groove, A s is the cross-sectional area of ​​the steel bars in the anchor groove.

[0100] like Figures 10 to 17 As shown, the present invention also provides a construction method for a new pipe-wrapped well in a hoisting structure of a new pipe-wrapped well for an existing pipeline, comprising the following steps:

[0101] Step 1: Level the construction site, build retaining piles and waterproof curtains on both sides of the existing pipeline, and reinforce the foundation pit;

[0102] Step 2: construct the top ring beam and the first support of the foundation pit. After the top ring beam and the first support reach the designed strength, excavate the earth in layers to the area 0.5m above the existing pipeline;

[0103] Step 3: Continue to dig downwards by manual excavation to reveal the scope of the existing pipeline, and dig to 0.25D below the center line of the existing pipeline, where D is the outer diameter of the existing pipeline;

[0104] Step 4: Locally excavate the soil under the existing pipeline, break the cushion layer under the existing pipeline, then place the steel beam under the existing pipeline and install the limit pad, and then set the steel wire rope to connect with the upper steel frame to ensure that the steel beam can effectively support the existing pipeline through the limit pad;

[0105] Step 5: Continue to excavate the soil downward to the designed elevation of the bottom of the foundation pit, including the thickness of the bottom plate and the cushion layer, and construct the cushion layer and bottom plate waterproof layer of the foundation pit;

[0106] Step 6: Tie the bottom plate reinforcement, wherein the reinforcement of the bottom plate located below the existing pipeline, the reinforcement parallel to the existing pipeline is fixed to the steel beam through the reinforcement anchor groove, and the gap in the reinforcement anchor groove is filled with self-compacting concrete, and then the concrete of the bottom plate is poured;

[0107] Step 7: After the bottom plate strength reaches the design requirements, remove the steel wire rope and the corresponding upper steel frame, and then pour the side wall of the newly built pipe well upwards;

[0108] Step 8: At the connection between the wall of the newly built pipe well and the existing pipeline, cut off the pipeline in the newly built pipe well, and then remove the abandoned pipe sections cut off in the newly built pipe well to achieve flow interception; then chisel out the top ring beam and the first support of the foundation pit, construct the top plate and top plate waterproof layer of the newly built pipe well, and then backfill and cover with soil.

[0109] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the existing technology should be within the scope of protection determined by the claims.

Claims

1. The hoisting structure of the newly built pipe-wrapped well of the existing pipeline includes a plurality of steel beams arranged below the existing pipeline for supporting the existing pipeline, and steel wire ropes arranged on both sides of the existing pipeline for suspending the steel beams; the characteristics are: Each of the steel beams includes a bearing surface on the upper side facing the existing pipeline; Three limiting pads are provided on each of the bearing surfaces corresponding to the arc-shaped outer side wall below the existing pipeline; The three limiting pads include a limiting pad A located directly below the center of the existing pipeline, and limiting pads B symmetrically arranged on both sides directly below the center of the existing pipeline; A steel bar anchoring groove is provided on the side of each of the steel beams; Each of the steel bar anchoring grooves is used to anchor the steel bars in the bottom plate parallel to the existing pipeline when constructing the bottom plate below the existing pipeline.

2. The hoisting structure for the newly constructed pipe well of the existing pipeline according to claim 1 is characterized in that: A lifting ring is provided on each of the steel beams at a position corresponding to the connection of the corresponding steel wire rope, and the lifting ring is connected to the corresponding steel wire rope.

3. The hoisting structure for the newly constructed pipe well of the existing pipeline according to claim 1 is characterized in that: Each of the A limit pads has a height of h1, a width of b1, and a length of w1; The height of each B limit pad close to the inner side of the center of the existing pipeline is h 21 , the height away from the center of the existing pipeline is h 22 , the width is the same as that of the corresponding A limit pad, both are b1; The distance from the center position of each B limit pad to the center of the existing pipeline, that is, the distance from the center position of each B limit pad to the center position of the corresponding A limit pad is d1; The outer diameter of the existing pipeline is D; b1,b2≥max{(0.02D+2×h1),(0.02D+0.04D)}; in, Each of the A limit pads and each of the B limit pads shall meet the compressive bearing capacity requirements: F L ≤1.35β L f c A L ; A L =0.02Dw1; Ab=min{(0.02D+2×h1)×w1, (0.02D+0.04D)×w1}; Among them, F L The weight of the pipeline borne by the steel beam; f c is the design value of the compressive strength of concrete; w1 is the length of the limit pad.

4. The hoisting structure for the newly built pipe well of the existing pipeline according to claim 1 is characterized in that: Each of the steel beams is an I-beam.

5. The hoisting structure for newly building a pipe-wrapped well for an existing pipeline according to claim 1 is characterized in that: The length of each of the steel bar anchor grooves is L s , the outer diameter of the existing pipeline is D; N=nf y A s ; Where σ is the tensile stress at the weld between the anchor groove and the steel web, L W h is the length of the welding seam between the anchor groove and the steel web; e is the calculated thickness of the weld connecting the anchor groove and the steel section, is the strength design value of the fillet weld, n is the number of steel bars in the anchor groove, and f y is the tensile strength of the steel bars in the anchor groove, A s is the cross-sectional area of ​​the steel bars in the anchor groove.

6. The construction method of a new pipe-wrapped well in the hoisting structure of a new pipe-wrapped well for an existing pipeline according to claim 1 is characterized in that: The steps include: Step 1: Level the construction site, construct retaining piles and water-blocking curtains on both sides of the existing pipeline, and reinforce the foundation pit; Step 2: construct the top ring beam and the first support of the foundation pit, and after the top ring beam and the first support reach the designed strength, excavate the earth in layers to the area 0.5m above the existing pipeline; Step 3, continue to dig downwards by manual excavation to reveal the scope of the existing pipeline, and dig to 0.25D below the center line of the existing pipeline, where D is the outer diameter of the existing pipeline; Step 4: excavate the soil below the existing pipeline locally, break the cushion layer under the existing pipeline, then place the steel beam under the existing pipeline and install the limit pad, and then set the steel wire rope to connect with the upper steel frame to ensure that the steel beam can effectively support the existing pipeline through the limit pad; Step 5: Continue to excavate the soil downward to the designed elevation of the bottom of the foundation pit, including the thickness of the bottom plate and the cushion layer, and construct the cushion layer and bottom plate waterproof layer of the foundation pit; Step 6, tying the bottom plate steel bars, wherein among the steel bars of the bottom plate located below the existing pipeline, the steel bars parallel to the existing pipeline are fixed to the steel beam through the steel bar anchoring groove, and the gap in the steel bar anchoring groove is filled with self-compacting concrete, and then the concrete of the bottom plate is poured; Step 7: After the bottom plate strength reaches the design requirements, remove the steel wire rope and the corresponding upper steel frame, and then pour the side wall of the newly built pipe well upwards; Step 8: At the connection between the wall of the newly built pipe-wrapped well and the existing pipeline, cut off the pipeline in the newly built pipe-wrapped well, then remove the abandoned pipe sections cut off in the newly built pipe-wrapped well to achieve flow interception; then chisel out the top ring beam and the first support of the foundation pit, construct the top plate and top plate waterproof layer of the newly built pipe-wrapped well, and then backfill and cover with soil.

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