Oblique-connection receiving construction process for receiving well

Abstract

The invention relates to the field of pipe jacking construction of underground engineering, in particular to a receiving well oblique connection and recovery construction process which is used for receiving the construction environment with soil pressure unbalance in a well, preventing oblique connection and recovery construction equipment from displacing, and replacing traditional high-pressure jet grouting pile reinforcement with horizontal pre-grouting in a hole. The influence of soil body reinforcement on the ground and pipelines above the construction line is effectively reduced, and the safety of tunnel portal breaking and pipe jacking receiving of the construction line is improved; by additionally arranging the Larsen steel sheet piles and the dewatering wells, the stability of a soil body outside a construction line tunnel opening is higher, the influence of the underground water level on construction is reduced, and the construction safety risk is further improved; a receiving steel platform is built, a reinforced concrete extension wall is manufactured on the receiving steel platform, the reinforced concrete extension wall is filled with foam concrete, a stable supporting platform is provided for receiving of the pipe jacking machine, and the pressure of soil on the two sides during oblique connecting and receiving is balanced through the synergistic effect of the reinforced concrete extension wall and the foam concrete; and the displacement risk of the pipe jacking machine is avoided.

Description

Technical Field

[0001] The invention relates to the field of underground engineering pipe jacking construction, in particular to a construction process for oblique receiving in a receiving well. Background Art

[0002] In urban underground construction, pipe jacking technology is widely used for laying pipelines across obstacles such as municipal roads, rivers, and buildings. However, with the increasing complexity of urban underground space development and utilization, the traditional orthogonal pipe jacking method is no longer able to meet actual project needs. This is especially true in complex environments such as those with limited receiving space, the presence of important buildings (structures), and dense underground pipelines. Oblique pipe jacking has become a necessary technical option.

[0003] At present, the existing jacking pipe oblique receiving process has the following shortcomings: Traditional soil reinforcement techniques, such as high-pressure jet grouting, are often used at the receiving end. However, when encountering pipelines within the reinforcement range, the limited space for reinforcement work makes it difficult to fully implement the reinforcement, which can easily disturb or even damage the pipelines. Furthermore, the reinforcement effect is uneven, posing a risk of soil collapse. The way the pipe jacking machine exits the tunnel poses a safety hazard. Due to the different ranges of entry into the station on both sides of the pipe jacking machine during oblique reception, after the pipe jacking machine is in place, one side is exposed to the air while the other side is affected by soil pressure. This can easily lead to an imbalance in soil pressure on both sides, causing the pipe jacking machine to move and even cause an accident. The receiving method is cumbersome and high-risk. In the existing technology, the pipe jacking machine cannot be completely removed from the hole in one go and needs to be disassembled in sections and then hoisted out. The disassembly and hoisting time is long, and the receiving tunnel is exposed for a long time, which poses a risk of collapse and water inrush, seriously affecting construction safety and progress. Summary of the Invention

[0004] In view of the problems existing in the above or prior art of the existing oblique jacking receiving process, such as poor soil reinforcement effect, high risk of displacement of the jacking machine, and complicated receiving method, the present invention is proposed.

[0005] Therefore, the object of the present invention is to provide a receiving well oblique receiving construction process.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: the oblique receiving construction process is applied to a construction environment with unbalanced earth pressure in a receiving well to prevent displacement of the oblique receiving construction equipment.

[0007] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, the oblique receiving construction equipment is set as a pipe jacking machine.

[0008] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, wherein: the moving path of the pipe jacking machine is set as the construction line, and when the pipe jacking machine is in place, the side of the lower part of the pipe jacking machine close to the receiving well is set as slope one, and the side of the upper part of the pipe jacking machine close to the receiving well is set as slope two, slope one is squeezed by the pipe jacking machine, and slope two is in an air-facing state.

[0009] As an optimal solution for the oblique receiving construction process of the receiving well of the present invention, wherein: S1: a construction line is provided with multiple groups of horizontal grouting ports; S2: dewatering wells are provided on both sides outside the construction line to lower the water level in the portal area of the construction line, and Larsen steel sheet piles are provided in the dewatering wells to stabilize the soil; S3: a receiving steel platform is built on the construction line, and a reinforced concrete extension wall is provided on the receiving steel platform, and foam concrete is filled in the reinforced concrete extension wall, which is interspersed with the demolition of the portal of the construction line; S4: the jacking machine stops jacking after it reaches the outer edge of the ground wall; S5: after the receiving state is stable, the reinforced concrete extension wall is removed, and the sealing is interspersed with the Larsen steel sheet piles; S6: the equipment in the casing is removed, temporary support is installed, and the front and rear casing socket parts are welded; S7: after the casing is cut off, secondary grouting and sealing are carried out, and finally the ring beam and the second lining in the shell are constructed to make the jacking channel flush with the middle plate, and the construction is completed.

[0010] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, the horizontal grouting port is expanded 3 meters outward from the construction line in the grouting range of the horizontal pre-grouting of the construction line, and the hole depth of the horizontal grouting port is ≤8100mm.

[0011] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, grouting material is arranged in the horizontal grouting port, the grouting material is double-liquid slurry, the grouting pressure is controlled at 2-4 bar, the grouting pressure above the construction line is not higher than 2 bar, and the horizontal grouting port adopts encrypted construction.

[0012] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, the double slurry is set as cement slurry and water glass.

[0013] As a preferred solution of the oblique receiving construction process of the receiving shaft of the present invention, wherein: the thickness of the reinforced concrete extension wall is set to be not less than 400mm and is connected to the receiving steel platform by welding; The construction joints created by welding between the reinforced concrete extension wall and the receiving steel platform were coated with epoxy resin sealing material.

[0014] As a preferred solution of the oblique receiving construction process of the receiving well of the present invention, the foam concrete has a strength grade not higher than 0.4MPa and a density of 350-450Kg / m³. The filling is carried out alternately with the demolition of the reinforced concrete extension wall and the protective layer. From bottom to top, every time one meter of demolition is completed, the foam concrete is filled to a depth of one meter.

[0015] As a preferred solution of the oblique receiving construction technology of the receiving well of the present invention, a receiving tunnel gate steel ring is provided at the port of the construction line, and the receiving tunnel gate steel ring is set to a parallelogram with a horizontal cross-section angle of °.

[0016] The beneficial effects of the receiving well oblique receiving construction process of the present invention are as follows: the present invention adopts horizontal pre-grouting in the hole to replace the traditional high-pressure rotary jet pile reinforcement, effectively reducing the impact of soil reinforcement on the ground and pipelines above the construction line, improving the safety of breaking the construction line tunnel and jacking pipe reception, and the grouting machine is simple to operate, the construction technology is flexible and controllable, the applicability is strong, and the reinforcement effect is guaranteed; By adding Larsen steel sheet piles and dewatering wells, the soil outside the construction tunnel is more stable, reducing the impact of groundwater levels on construction and further improving construction safety risks; By building a receiving steel platform and constructing a reinforced concrete extension wall on it, and filling the reinforced concrete extension wall with foam concrete, it not only provides a stable support platform for the pipe jacking machine to receive, but also balances the soil pressure on both sides during oblique reception through the synergistic effect of the reinforced concrete extension wall and foam concrete, thus avoiding the risk of displacement of the pipe jacking machine; The optimized pipe jacking receiving process realizes the efficient reception of the pipe jacking machine, avoids the risk of long-term tunnel exposure caused by the disassembly and lifting of the pipe jacking machine in sections in the traditional receiving method, and reduces the cost and risk of using large lifting equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a schematic diagram of the construction process of the oblique receiving construction technology of the receiving well.

[0019] Figure 2 This is a schematic diagram of the horizontal grouting process for the oblique receiving construction process of the receiving well.

[0020] Figure 3 This is a schematic diagram of the grouting point distribution for the oblique receiving construction technology of the receiving well.

[0021] Figure 4 Schematic diagram of Larsen steel sheet piles for the oblique receiving construction process of the receiving well.

[0022] Figure 5 Schematic diagram of the foam concrete filling structure in the reinforced concrete extension wall of the receiving well oblique receiving construction process.

[0023] Figure 6 It is a structural diagram of the receiving well oblique receiving construction process when it is jacked into place.

[0024] Figure 7 This is an aerial view of the pipe jacking reception in the receiving well's oblique receiving construction technology.

[0025] Figure 8 This is a front view of the pipe jacking reception in the receiving well oblique receiving construction process.

[0026] Description of the accompanying drawings: 1. Construction route; 2. Slope 1; 3. Slope 2; 4. Horizontal grouting port; 5. Dewatering well; 6. Larsen steel sheet pile; 7. Receiving steel platform; 8. Reinforced concrete extension wall; 9. Foam concrete; 10. Temporary support; 11. Receiving portal steel ring. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0028] Reference Figures 1-8 , which is the first embodiment of the present invention, provides a receiving well oblique receiving construction process, which includes applying the oblique receiving construction process to a construction environment with unbalanced soil pressure in the receiving well to prevent the oblique receiving construction equipment from being displaced.

[0029] Among them, the oblique receiving construction equipment is set as a pipe jacking machine.

[0030] Among them, the moving path of the pipe jacking machine is set as construction route 1. When the pipe jacking machine is in place, the side of the lower part of the pipe jacking machine close to the receiving well is set as slope 1 2, and the side of the upper part of the pipe jacking machine close to the receiving well is set as slope 2 3. Slope 1 2 is squeezed by the pipe jacking machine, and slope 2 3 is in an air-exposed state.

[0031] The embodiment provides a receiving well oblique receiving construction process which further includes the following steps: S1: Construction line 1 is provided with multiple sets of horizontal grouting ports 4 for grouting to reinforce the openings of construction line 1; S2: Dewatering wells 5 are set up on both sides of the construction line 1 to lower the water level in the portal area of the construction line 1. The filter pipe diameter of the dewatering well is 325mm, and the dewatering radius completely covers the receiving end. Pumping and drainage are continued until the construction of the receiving ring beam is completed. Larsen steel sheet piles 6 are installed in the dewatering well 5 to stabilize the soil. The Larsen steel sheet piles 6 are 35 conventional SP-III type Larsen steel sheet piles and 2 corner piles. S3: A receiving steel platform 7 is built on construction route 1 to provide support and reinforcement. The receiving steel platform 7 includes 24 Ø609 steel supports, which are connected by 14# channel steel. Six 45b steel purlins are longitudinally installed on the steel supports and welded to the steel supports. 43 steel rails are transversely installed on the steel purlins with a spacing of 150mm and welded to the steel purlins. The top is fully paved with 10mm thick steel plates, which are firmly welded together. A reinforced concrete extension wall 8 is set on the receiving steel platform 7. The reinforced concrete extension wall 8 is filled with foam concrete 9 to reduce the pressure of the pipe jacking machine on the soil at the construction route 1 tunnel entrance. The demolition of the tunnel entrance of construction route 1 is interspersed with the demolition of the tunnel entrance of construction route 1. S4: The pipe jacking machine stops pushing after reaching the outer edge of the ground wall; S5: After the receiving state is stable, the reinforced concrete extension wall 8 is dismantled and the Larsen steel sheet pile 6 is used for blocking. The extension wall is demolished in three layers. After each layer is demolished from top to bottom, it is immediately sealed with steel plates. The 20cm gap between the pipe joint and the construction line 1 portal is reliably and tightly welded with steel plates. The welding process ensures that the width of the 300mm receiving portal steel ring 11 ring beam is not restricted; S6: Remove the equipment inside the casing, install temporary support 10, and weld the front and rear casing socket parts; S7: After cutting off the casing, secondary grouting is carried out to seal it. After the casing of the pipe jacking machine is cut, 280mm of the left casing is retained. Finally, the ring beam and the secondary lining inside the shell are constructed to make the pipe jacking channel flush with the middle plate, and the construction is completed. The grouting positions for the secondary grouting include between the receiving well entrance and the pipe jacking piece, between the main extension wall and the receiving well entrance, and between the main extension wall and the auxiliary extension wall.

[0032] Among them, the grouting range of the horizontal pre-grouting of the horizontal grouting port 4 in the construction line 1 expands 3 meters outward from the construction line 1, and the hole depth of the horizontal grouting port 4 is ≤8100mm.

[0033] Among them, grouting material is set in the horizontal grouting port 4, the grouting material is double liquid slurry, the grouting pressure is controlled at 2-4 bar, the grouting pressure above the construction line 1 is not higher than 2 bar, and the horizontal grouting port 4 adopts encrypted construction.

[0034] Among them, the double liquid slurry is set as cement slurry and water glass.

[0035] The reinforced concrete extension wall 8 is set to be no less than 400 mm thick and is connected to the receiving steel platform 7 by welding; The construction joint produced by welding between the reinforced concrete extension wall 8 and the receiving steel platform 7 is coated with epoxy resin sealing material.

[0036] Among them, the foam concrete 9 has a strength grade not higher than 0.4MPa and a density of 350-450Kg / m³. Its filling is interspersed with the demolition of the reinforced concrete extension wall 8 and the protective layer. From bottom to top, every time one meter of demolition is completed, the foam concrete 9 is filled to a depth of one meter.

[0037] Among them, a receiving tunnel gate steel ring 11 is provided at the port of the construction line 1, and the receiving tunnel gate steel ring 11 is set as a parallelogram with a horizontal cross-section of 47°.

[0038] In summary, when constructing the side walls of the tunnel portal of Construction Route 1, horizontal grouting openings 4 were reserved above and on both sides of the tunnel portal of Construction Route 1. Due to obstruction from the side walls, some areas required oblique drilling and grouting to ensure the strength of the wall. The reinforcement range extended 3 meters above and below the inner wall of Construction Route 1, and the hole depth was controlled to be ≤8100mm. Cement slurry and water glass were used as grouting materials, and grouting was carried out alternately. The grouting pressure was controlled at 2-4 bar, and the grouting pressure above the tunnel portal was not higher than 2 bar. During the grouting process, a dedicated person was arranged on the ground to supervise, and the monitoring point map accurately marked the location of important pipelines, and the monitoring frequency was increased. At this time, two dewatering wells 5 were added on both sides of the tunnel portal of construction line 1. The filter diameter of dewatering well 5 was set to 325mm, and the dewatering radius completely covered the receiving end. This allowed continuous pumping and drainage before the construction of the receiving ring beam was completed, lowering the water level in the tunnel portal area of construction line 1 and reducing the impact of groundwater on construction. At this time, a layer of Larsen steel sheet piles 6 is driven outside the tunnel portal of construction line 1. 35 conventional SP-III type Larsen steel sheet piles 6 and 2 corner piles are selected to form the steel sheet pile support. When the steel sheet pile support is completed, the demolition work of the tunnel portal of construction line 1 begins. After the foam concrete 9 is filled, it is removed and cement slurry is poured into the pile hole to close the water seepage channel. At this time, a receiving steel platform 7 is built at the exit of the pipe jacking machine in the construction line 1, and a reinforced concrete extension wall 8 with a wall thickness of 400mm is made on the receiving steel platform 7. The steel bars on the reinforced concrete extension wall 8 are connected to the receiving steel platform 7 by welding, and connected to the structural wall by planting bars. The construction joints are coated with epoxy resin sealing material. After the tunnel portal is broken, low-grade foam concrete 9 is poured within the temporary extension wall and the enclosed range of the receiving tunnel portal. The strength grade of the foam concrete 9 is not higher than 0.4MPa and the density is 350-450Kg / m³. The filling of the foam concrete 9 is interspersed with the breaking of the steel bars and protective layer on the soil surface. From bottom to top, every time 1 meter is broken, the foam concrete 9 is filled to a depth of 1 meter to balance the soil pressure on both sides and avoid displacement of the pipe jacking machine. When the pipe jacking machine reaches the outer edge of the ground wall, it stops pushing. The shovel teeth of the pipe jacking machine push to the outer edge of the ground wall and the jacking is in place. The length of the pipe jacking machine shell is 4744mm. After calculation, after the cutting of the pipe jacking machine shell is completed, 280mm of the left shell can still be retained. At this time, the reinforced concrete extension wall 8 is broken and the steel plate is blocked alternately. The breaking is carried out in three layers. From top to bottom, as one layer is broken, a layer is immediately blocked with steel plate welding until all the welding is completed. At this time, the equipment in the casing is removed and a temporary support 10 is installed. At the same time, the socket parts of the front and rear casings are welded to prevent the remaining parts from deforming during the casing removal process. At this time, secondary grouting is carried out on parts such as the reinforced concrete extension wall 8, and then the temporary support 10 inside the construction line 1 is removed. Then, the ring beam and the secondary lining inside the shell are constructed according to the design drawings, so that the top pipe channel is flush with the middle plate, restoring the integrity and stability of the structure.

[0039] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A receiving well oblique receiving construction process, characterized by: The oblique receiving construction process is applied to a construction environment where the soil pressure in the receiving well is unbalanced, so as to prevent displacement of oblique receiving construction equipment.

2. The receiving well oblique receiving construction process according to claim 1, characterized in that: The oblique receiving construction equipment is set as a pipe jacking machine.

3. The receiving well oblique receiving construction process according to claim 2, characterized in that: The moving path of the pipe jacking machine is set as the construction route (1). When the pipe jacking machine is pushed into place, the side of the receiving well close to the lower part of the pipe jacking machine is set as the slope 1 (2), and the side of the receiving well close to the upper part of the pipe jacking machine is set as the slope 2 (3). The slope 1 (2) is squeezed by the pipe jacking machine, and the slope 2 (3) is in an air-free state.

4. The receiving well oblique receiving construction process according to claim 3 comprises the following steps, characterized in that: S1: The construction line (1) is provided with multiple sets of horizontal grouting ports (4); S2: Dewatering wells (5) are provided on both sides of the construction line (1) to lower the water level in the tunnel area of the construction line (1), and Larsen steel sheet piles (6) are provided in the dewatering wells (5) to stabilize the soil; S3: The construction route (1) builds a receiving steel platform (7), a reinforced concrete extension wall (8) is set on the receiving steel platform (7), and foam concrete (9) is filled in the reinforced concrete extension wall (8), which is interspersed with the demolition of the tunnel door of the construction route (1); S4: The pipe jacking machine stops pushing after reaching the outer edge of the ground wall; S5: After the receiving state is stable, the reinforced concrete extension wall (8) is dismantled and interleaved with the Larsen steel sheet pile (6) for blocking; S6: Remove the equipment inside the casing, install temporary supports (10), and weld the front and rear casing socket parts; S7: After cutting off the casing, secondary grouting is carried out to seal it. Finally, the ring beam and the secondary lining inside the shell are constructed to make the jacking channel flush with the middle plate, and the construction is completed.

5. The receiving well oblique receiving construction process according to claim 4, characterized in that: The grouting range of the horizontal grouting port (4) in the horizontal pre-grouting of the construction line (1) is expanded 3 meters outward from the construction line (1), and the hole depth of the horizontal grouting port (4) is ≤8100mm.

6. The receiving well oblique receiving construction process according to claim 5, characterized in that: Grouting material is provided in the horizontal grouting port (4), the grouting material is double-liquid slurry, the grouting pressure is controlled at 2-4 bar, the grouting pressure above the construction line (1) is not higher than 2 bar, and the horizontal grouting port (4) adopts dense construction.

7. The receiving well oblique receiving construction process according to claim 6, characterized in that: The double-liquid slurry is set up as cement slurry and water glass.

8. The construction process for receiving well oblique intersection as claimed in claim 7, characterized in that: The reinforced concrete extension wall (8) is set to a thickness of not less than 400 mm and is connected to the receiving steel platform (7) by welding; The construction joints produced by welding between the reinforced concrete extension wall (8) and the receiving steel platform (7) are coated with epoxy resin sealing material.

9. The receiving well oblique receiving construction process according to claim 8, characterized in that: The foam concrete (9) has a strength grade not higher than 0.4 MPa and a density of 350-450 kg / m³. The filling is carried out in an interlaced manner with the demolition of the reinforced concrete extension wall (8) and the protective layer. From bottom to top, each time one meter of demolition is completed, the foam concrete (9) is filled to a depth of one meter.

10. The receiving well oblique receiving construction process according to claim 9, characterized in that: A receiving tunnel gate steel ring (11) is provided at the port of the construction line (1), and the receiving tunnel gate steel ring (11) is provided in the form of a parallelogram with a horizontal cross section of 47 degrees.

Images