Construction method of immersed tube pre-embedded subway wastewater pump house

Abstract

A construction method of an immersed tube pre-embedded subway wastewater pump house comprises the steps that a hole is dug downwards in the ground surface of a to-be-excavated tunnel, a pre-embedded tube is placed in the hole, a blanking cap for preventing underground water from spewing is additionally installed on the top of the pre-embedded tube subsequently, then peripheral cement mortar is filled, earthwork is backfilled and compacted, and the immersed tube pre-embedded subway wastewater pump house is constructed. Then, a tunnel is excavated according to the set position, grouting is conducted between a tunnel segment and the embedded pipe to manufacture a water-resisting layer, finally, the tunnel and the embedded pipe are excavated and communicated, a reinforcing channel is installed, a water pump, a water pipe and corresponding lines are placed in, and construction of the immersed pipe embedded type subway waste water pump room is completed. Compared with a traditional construction method, the construction is easier to implement, construction does not need to be carried out in a foundation of an existing connection channel, the time needed for construction is shorter, the cost is greatly reduced, the risk is remarkably reduced, and the construction period is obviously shortened.

Description

Technical Field

[0001] The invention relates to the technical field of subway wastewater pump house construction, in particular to a construction method for a immersed tube pre-buried subway wastewater pump house. Background Art

[0002] The wastewater pump room is a structure for storing wastewater in subway tunnel facilities. It can discharge wastewater from the tunnel after the water reaches the set depth, preventing wastewater from accumulating and directly entering the tunnel to cause pollution. Most of the subway pump rooms in existing tunnel facilities are located at the bottom of the connecting channel between the two tunnels. It is necessary to first dig a connecting channel between the two tunnels, and then carry out construction at the bottom of the connecting channel. The construction of existing connecting channels mostly uses freezing method or mechanized excavation construction. The overall construction time is long, the cost is high, the risk is high, the construction period is slow, and the space in the connecting channel is limited, which is not conducive to the construction of the wastewater pump room inside. Summary of the invention

[0003] The purpose of the present invention is to provide a method for constructing a pre-buried immersed tube subway wastewater pump room, which replaces the traditional construction method in the communication channel by pre-digging holes to install pre-buried pipes and then digging tunnels and opening them up, thereby solving the problems in the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a method for constructing a pre-buried subway wastewater pump room with an immersed tube, comprising the following steps: ① on the surface of the preset excavation position of the tunnel, use a drilling rig to dig a hole downward, and the hole is arranged perpendicular to the cross-section of the tunnel to be excavated; ② after the excavation of the hole in step ① is completed, use a crane to lift the embedded pipe into the hole, and let the embedded pipe fall to the bottom position of the hole; ③ after the embedded pipe in step ② is installed, install a plugging cover on the top of the embedded pipe to prevent groundwater from gushing; ④ after the plugging cover in step ③ is installed, fill cement mortar on the periphery of the embedded pipe and the upper side of the plugging cover; ⑤ after the cement mortar filled in step ④ solidifies to form a first waterproof layer, backfill the hole with earth and perform compaction operation; ⑥ after the backfilling of earth in step ⑤ is completed, carry out tunneling according to the set position. Excavation support and installation of pipe segments, wherein the bottom tunnel pipe segment is located at a set distance above the plugging cover; ⑦ After the tunnel pipe segment is installed in step ⑥, a grouting hole is opened on the outer periphery of the pipe segment on the upper part of the pre-buried pipe, and cement slurry is injected into the grouting hole to form a second annular waterproof layer on the outer periphery of the tunnel, wherein the second waterproof layer and the first waterproof layer are solidified as one; ⑧ After the second waterproof layer in step ⑦ is completed, the tunnel pipe segment is excavated downward, the first waterproof layer and the second waterproof layer are excavated to the plugging cover position, and a reinforcement channel is installed in the excavated area, and both ends of the reinforcement channel connected to the tunnel and the plugging cover use an orifice sealing device; ⑨ After the reinforcement channel in step ⑧ is installed, the water pump, water pipe and corresponding lines are placed in the pre-buried pipe, and drainage holes and pumping holes are reserved on the tunnel to complete the construction of the immersed tube pre-buried subway wastewater pump room. Before backfilling the earthwork in step ⑤, fill the outer periphery and top position of the pre-buried pipe with a thickness of 1m of cement mortar. The embedded pipe is a reinforced concrete pipe, and a bottom plate is provided at the bottom of the embedded pipe. The distance between the plugging cover and the upper tunnel segment is 20-40 cm. The thickness of the connecting reinforcement channel is 10-20 cm. The wall thickness of the embedded pipe is 20-30 cm, the diameter is 1-1.5 m, and the height is 3-5 m.

[0005] The positive effect of the present invention is that: the construction method of a pre-buried subway wastewater pump house of the present invention is to dig a hole downward on the surface of the ground at the location of the tunnel to be excavated, put the pre-buried pipe in the hole, and then install a plugging cover on the top of the pre-buried pipe to prevent groundwater from gushing, and then fill the outer periphery with cement mortar, and backfill and compact the earth, and then dig out the tunnel according to the set position, and grouting is performed between the tunnel segment and the pre-buried pipe to make a waterproof layer, and finally the tunnel is excavated and connected with the pre-buried pipe and a reinforced channel is installed, and a water pump, water pipe and corresponding lines are placed to complete the construction of the pre-buried subway wastewater pump house of the immersed tube. Compared with the traditional construction method, the above construction is easier to implement, and there is no need to carry out construction on the basis of the existing communication channel. The time required for construction is shorter, the cost is greatly reduced, the risk is significantly reduced, and the construction period can be significantly shortened. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is a schematic diagram of the state after step ① of the present invention is completed; Figure 2 This is a schematic diagram of the state after step ② of the present invention is completed; Figure 3 This is a schematic diagram of the state after step ③ of the present invention is completed; Figure 4 This is a schematic diagram of the state after step ④ of the present invention is completed; Figure 5 This is a schematic diagram of the state after step ⑤ of the present invention is completed; Figure 6 This is a schematic diagram of the state after step ⑥ of the present invention is completed; Figure 7 This is a schematic diagram of the state after step ⑦ of the present invention is completed; Figure 8 This is a schematic diagram of the state after step ⑧ of the present invention is completed; Fig. 9 It is a schematic diagram of the state after step ⑨ of the present invention is completed. DETAILED DESCRIPTION

[0007] The invention discloses a method for constructing a pre-buried immersed tube subway wastewater pump house. Figure 1-9 As shown, the following steps are included: ① On the surface of the preset tunnel excavation position, a hole 1 is dug downwards using a drilling machine, and the hole 1 is arranged perpendicular to the tunnel section to be excavated; ② After the excavation of the hole 1 in step ① is completed, the embedded pipe 2 is hoisted into the hole 1 by a crane, and the embedded pipe 2 is lowered to the bottom of the hole 1. The specific size of the embedded pipe 2 can be adaptively replaced according to the design space requirements to meet the space requirements of the wastewater pump room; ③ After the pre-buried pipe 2 in step ② is installed, a plugging cover 5 is installed on the top of the pre-buried pipe 2 to prevent groundwater from gushing out; ④ After the plugging cover 5 in step ③ is installed, cement mortar is filled to the outer periphery of the embedded pipe 2 and the upper side of the plugging cover 5; ⑤ After the cement mortar filled in step ④ solidifies to form the first waterproof layer 3, backfill the hole 1 with earth and perform compaction operation; ⑥ After the backfilling in step ⑤ is completed, the tunnel excavation support and pipe segment installation are carried out according to the set position, wherein the bottom tunnel pipe segment is located at a set distance above the plugging cover 5; ⑦ After the tunnel segments are installed in step ⑥, a grouting hole 6 is opened on the outer periphery of the segments at the upper part of the embedded pipe 2, and cement slurry is injected into the grouting hole 6 to form an annular second waterproof layer 4 on the outer periphery of the tunnel, wherein the second waterproof layer 4 and the first waterproof layer 3 are solidified into one; ⑧ After the second waterproof layer 4 in step ⑦ is completed, dig downward in the tunnel segment, dig through the first waterproof layer 3 and the second waterproof layer 4 to the position of the plugging cover 5, and install the reinforcement channel 7 in the excavated area, and both ends of the reinforcement channel 7 connected to the tunnel and the plugging cover 5 use orifice sealing devices; ⑨ After the installation of the reinforcement channel 7 in step ⑧ is completed, the water pump 8, water pipe 9 and corresponding lines are placed in the pre-buried pipe 2, and drainage holes and pumping holes are reserved on the tunnel to complete the construction of the immersed tube pre-buried subway wastewater pump room.

[0008] The above construction method is to dig a hole downward above the surface and pre-bury the sewage pump house at the preset excavation length of the tunnel before tunnel excavation. Compared with the traditional method of digging sewage pump houses between tunnels after the tunnels are built, the construction time is shorter, the cost is greatly reduced, the risk is significantly reduced, and the construction period is significantly shortened.

[0009] In step ①, digging a hole downward on the surface of the ground provides a wider working space than construction in the tunnel, which is convenient for the use of large-scale mechanical equipment. At the same time, digging a hole 1 downward at the location where the tunnel is set to be excavated can ensure that the wastewater pump room set up in the hole 1 can be connected to the tunnel and play a corresponding role in collecting wastewater. The pre-buried pipe 2 hoisted and lowered in step ② serves as the outer foundation structure of the wastewater pump room. Step ③ is to install a plugging cover 5 on the top of the pre-buried pipe 2, so that the pre-buried pipe 2 can be used as a closed container as a wastewater pump room. After the subsequent tunnel is built, when digging and opening from the inside of the tunnel to the location of the wastewater pump room, the setting of the plugging cover 5 can effectively prevent the groundwater in the pre-buried pipe 2 from gushing into the tunnel and affecting the various facilities inside it.

[0010] Step ④ is to fill the outer periphery of the embedded pipe 2 and the upper side of the plugging cover 5 with cement mortar after installing the plugging cover 5 to form the first waterproof layer 3 to isolate the groundwater. Step ⑤ is to backfill and compact the earth in the hole 1. After the embedded pipe 2 serving as the wastewater pump room is installed in the set position under the surface, the previously excavated hole 1 is filled to facilitate the subsequent normal tunnel excavation in the stratum.

[0011] Step ⑥ is to excavate the tunnel and lay the pipe segments. The tunnel to be excavated is located at the set position above the wastewater pump house, leaving a certain distance between the tunnel and the wastewater pump house. The purpose of this is to prevent the pre-buried wastewater pump house from becoming an interference obstacle during the tunnel excavation process, ensuring the normal progress of the sequential construction.

[0012] After the tunnel construction is completed, the partition between the tunnel and the sewage pump room needs to be dug through. In order to prevent groundwater from gushing into the tunnel during the excavation process, in step ⑦, grouting holes 6 need to be opened around the tunnel before excavation, and cement slurry needs to be injected into the grouting holes 6 to form a second waterproof layer 4 on the outer periphery of the tunnel and the embedded pipe 2, which solidifies into one with the first waterproof layer 3 and together becomes a waterproof guarantee when it is opened later, preventing groundwater from entering the tunnel or the sewage pump room.

[0013] In the subsequent excavation process, the first waterproof layer 3 and the second waterproof layer 4 are dug through to the position of the plugging cover 5, and a reinforced channel 7 is installed in the excavated area to further prevent water leakage. After the installation of the reinforced channel 7 is completed, the water pump 8, water pipe 9 and the corresponding lines are placed in the pre-buried pipe 2. After the various facilities and devices inside the wastewater pump room are installed, the construction of the immersed tube pre-buried subway wastewater pump room is completed. Drainage holes and pumping holes corresponding to the water pipe 9 can be opened on the plugging cover 5 and the tunnel to facilitate the water pipe 9 to pass through and realize normal pumping or drainage functions.

[0014] Furthermore, before backfilling the earth in step ⑤, 1 m thick cement mortar is filled on the periphery and top of the embedded pipe 2. When the tunnel segment and the embedded pipe 2 are penetrated in the later stage, holes can be drilled in the filled cement mortar, that is, grouting holes 6 are opened in the cement mortar, wherein the cement mortar layer can form a relatively closed space on the periphery of the embedded pipe 2, thereby preventing the connection between the tunnel segment and the embedded pipe 2 from being affected by water seepage from the periphery of the tunnel during the penetration operation, thereby preventing water leakage.

[0015] Furthermore, in order to improve the durability of the embedded pipe 2 as a wastewater pump room, the embedded pipe 2 is a reinforced concrete pipe. In order to prevent groundwater from entering the embedded pipe 2, a bottom plate is provided at the bottom of the embedded pipe 2.

[0016] Furthermore, in order to leave enough safe construction space between the top of the wastewater pump room and the tunnel during subsequent tunnel excavation to ensure normal tunnel excavation operations, the distance between the plugging cover 5 and the upper tunnel segment is 20-40 cm, and the distance between the buried position of the pipeline and the bottom of the tunnel segment is 20-30 cm.

[0017] Furthermore, in order to ensure the strength of the connection reinforcement body channel 7 and prevent groundwater from entering the tunnel through the connection reinforcement body channel 7, the thickness of the connection reinforcement body channel 7 is 10-20 cm.

[0018] Furthermore, the wall thickness of the embedded pipe 2 is 20-30 cm, the diameter is 1-1.5 m, and the height is 3-5 m.

[0019] The technical solution of the present invention is not limited to the scope of the embodiments described in the present invention. The technical contents not described in detail in the present invention are all well-known technologies.

Claims

1. A method for constructing a pre-buried immersed tube subway wastewater pump house, characterized in that: The method comprises the following steps: ① using a drilling machine to dig a hole (1) downward on the ground surface at a preset tunnel excavation location, wherein the hole (1) is arranged perpendicular to the cross section of the tunnel to be excavated; ② After the excavation of the hole (1) in step ① is completed, a crane is used to lift the embedded pipe (2) into the hole (1), so that the embedded pipe (2) is lowered to the bottom of the hole (1); ③ After the pre-buried pipe (2) in step ② is installed, a plugging cover (5) is installed on the top of the pre-buried pipe (2) to prevent groundwater from gushing out; ④ After the plugging cover (5) in step ③ is installed, cement mortar is filled on the outer periphery of the embedded pipe (2) and the upper side of the plugging cover (5); ⑤ After the cement mortar filled in step ④ solidifies to form the first waterproof layer (3), backfill the hole (1) with earth and perform compaction operation; ⑥ After the backfilling in step ⑤ is completed, the tunnel excavation support and pipe segment installation are carried out according to the set position, wherein the bottom tunnel pipe segment is located at a set distance above the plug cover (5); ⑦ After the tunnel segments are installed in step ⑥, a grouting hole (6) is opened on the outer periphery of the segments on the upper part of the embedded pipe (2), and cement slurry is injected into the grouting hole (6) to form an annular second waterproof layer (4) on the outer periphery of the tunnel, wherein the second waterproof layer (4) and the first waterproof layer (3) are solidified into one; ⑧ After the second waterproof layer (4) in step ⑦ is completed, dig downwards in the tunnel segment, dig through the first waterproof layer (3) and the second waterproof layer (4) to the position of the plugging cover (5), and install a reinforcement channel (7) in the excavated area, and use orifice sealing devices at both ends of the reinforcement channel (7) connected to the tunnel and the plugging cover (5); ⑨ After the installation of the reinforcement channel (7) in step ⑧ is completed, the water pump (8), water pipe (9) and corresponding lines are placed in the pre-buried pipe (2), and drainage holes and pumping holes are reserved on the tunnel to complete the construction of the immersed tube pre-buried subway wastewater pump room.

2. The method for constructing a pre-buried immersed tube subway wastewater pump house according to claim 1, characterized in that: Before backfilling the earth in step ⑤, fill the outer circumference and top of the embedded pipe (2) with a 1m thick cement mortar.

3. The method for constructing a pre-buried immersed tube subway wastewater pump house according to claim 1, characterized in that: The embedded pipe (2) is a reinforced concrete pipe, and a bottom plate is provided at the bottom of the embedded pipe (2).

4. The method for constructing a pre-buried immersed tube subway wastewater pump house according to claim 1, characterized in that: The distance between the plugging cover (5) and the upper tunnel segment is 20-40 cm.

5. The method for constructing a pre-buried immersed tube subway wastewater pump house according to claim 1, characterized in that: The thickness of the connecting reinforcement channel (7) is 10-20 cm.

6. The method for constructing a pre-buried immersed tube subway wastewater pump house according to claim 1, characterized in that: The wall thickness of the embedded pipe (2) is 20-30 cm, the diameter is 1-1.5 m, and the height is 3-5 m.

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