Subway shaft limited space shield split launching technology

Abstract

The invention belongs to the field of metro construction, and particularly relates to a metro shaft limited space shield split launching technology which successfully solves the problem that a traditional integral launching mode is difficult to implement in a limited space by connecting a shield tunneling machine body, an equipment bridge and a trolley part in a split mode and assembling step by step according to the tunneling progress. The method has the remarkable advantages that the construction space requirement is reduced, the construction difficulty and cost are reduced, the construction flexibility and adaptability are improved, and the construction safety and quality are guaranteed, and an efficient, economical and safe solution is provided for construction under the complex geological conditions of urban subway tunnels and the like.

Description

Technical Field

[0001] The invention relates to the field of subway construction, and in particular to a subway shaft limited space shield split starting technology. Background Art

[0002] The shield machine starting link is a crucial link in the shield construction method. There are two main types of traditional shield machine starting modes: overall starting and split starting. Overall starting is usually suitable for scenes with a large construction space. When the shield machine starts at a station or a large shaft, the shield body of the shield machine can be hoisted into the starting end together with the supporting trolley, and the shield body can be connected as a whole to start excavation. However, in actual projects, it is often encountered that the construction space is limited, such as only one shaft and a dark excavation section, wind pavilion and other starting construction conditions. At this time, the overall starting method seems to be unable to meet the needs.

[0003] When starting shield construction in a limited space, if the overall starting method is adopted, it may be necessary to construct additional slag pits and hoisting pits, which not only increases the construction cost, but may also extend the construction period and bring potential safety hazards to the construction. Therefore, it is necessary to develop a more flexible and efficient shield starting technology for construction conditions in such limited spaces. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a subway shaft limited space shield split starting technology to solve the existing problems.

[0005] To achieve the above object, the present invention provides the following technical solution: subway shaft limited space shield split starting technology, including the following steps:

[0006] S1, under the construction condition of only one shaft and one dark excavation section, the shield machine body is connected with the equipment bridge and the trolley part separately;

[0007] S2, divides the origination process into three stages:

[0008] S21, the shield machine mainframe is located underground, the equipment bridge, connecting bridge and trolley are placed on the ground, and are connected by extended pipelines to complete the first stage of shield excavation;

[0009] S22: When the tunnel is excavated to a length that can accommodate the length of the connecting bridge and the No. 1 trolley, the equipment bridge, the No. 1 trolley and the shield are connected, and the No. 2 to No. 5 trolleys are temporarily placed on the ground;

[0010] S23: When the tunnel is excavated to a length that can accommodate the equipment bridge and the length of all trolleys, trolleys No. 2 to 6 are connected to trolley No. 1 and the normal excavation stage begins.

[0011] Optionally, in step S21, the following steps are also included:

[0012] S211, segment transportation and assembly stage, each ring of segments is vertically hoisted down the well for assembly by using the gantry crane on the well several times through the gap between the screw machine and the reaction frame;

[0013] S212, other materials are hoisted and lowered into the well by gantry crane just like the segment transportation;

[0014] S213, when assembling the negative ring segments, pay attention to the segment assembly quality and the reinforcement of the segments that have come out of the shield tail.

[0015] Optionally, in step S22, the following steps are also included:

[0016] S221, after the shield enters the hole, use the pipe segments with specified width to assemble the ring;

[0017] S222, use a self-made slag bucket placed on the slag flat plate, and use a winch to pull it to ensure cyclic construction;

[0018] S223, the transportation of pipe segments is carried out simultaneously with the transportation of slag, and the single piece is hoisted horizontally and transported down the well;

[0019] S224, synchronous grouting slurry is pumped to the shield tail grouting pipe using an extended slurry pipe at the starting well;

[0020] S225, when the tunnel gate is blocked, the shield driver monitors the grouting volume and pressure in real time, advances the shield machine a short distance at the right time and strengthens the injection of grease at the shield tail.

[0021] Optionally, in step S23, the following steps are also included:

[0022] S231, remove the top segment of the negative ring and replace it with a steel support;

[0023] S232, the steel support is connected to the pipe segment and the reaction frame by steel plates and bolts, and triangular steel plate supports and steel bars are welded to form an integral structure.

[0024] Optionally, it also includes the use of battery vehicles to improve safety and work efficiency in the subsequent excavation stage. Specifically: when discharging slag, the battery vehicle is composed of a machine head and a slag bucket. After the lower space of the shield machine's screw machine is full of slag, it is towed to the wellhead and the slag bucket and flat plate are lifted to the ground for vertical transportation of segments and materials. In the tunnel, the battery vehicle is used to horizontally pull the single segment to the assembly surface for assembly.

[0025] Optionally, this technology is suitable for shield tunneling construction scenarios with complex surrounding environments and limited construction space. The split starting method greatly utilizes the construction space, shortens the construction period, reduces construction costs, and ensures construction safety.

[0026] The beneficial effects of the present invention are:

[0027] 1) Reduced construction space requirements: This technology significantly reduces the amount of excavation of the starting shaft by assembling the shield machine into multiple modules, thereby reducing the demand for construction space. This is particularly important for tunnel construction in urban centers or other space-constrained areas, and can effectively reduce the cost and time of land acquisition, demolition and pipeline relocation.

[0028] 2) Reduce construction difficulty and cost: Since the excavation of the starting well is reduced, the construction difficulty and cost are also reduced accordingly. In addition, the split starting technology can also flexibly adjust the assembly method according to actual conditions to adapt to different geological and construction conditions, further improving construction efficiency and economy.

[0029] 3) Improve construction flexibility and adaptability: The subway shaft limited space shield split start technology is suitable for various complex geological conditions, such as soft soil, silt, karst, faults and abundant groundwater. Through split assembly and debugging, it can better cope with these complex geological conditions and improve construction flexibility and adaptability.

[0030] 4) Ensure construction safety and quality: This technology has high requirements for construction accuracy, and requires the use of high-precision positioning and control systems to ensure that the connections between modules are firm and leak-free. This helps reduce safety hazards during construction and improve the quality and safety of tunnel construction.

[0031] 5) Promote the innovation and development of shield construction technology: The successful application of the shield split-starting technology in the limited space of the subway shaft not only solves the problem of shield starting in a limited space, but also provides new ideas and directions for the innovation and development of shield construction technology. This will help promote the continuous progress of shield construction technology and the expansion of its application areas.

[0032] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0034] Figure 1 It is a schematic diagram of the overall process of the present invention. DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0036] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0037] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0038] See also Figure 1 , which is a subway shaft limited space shield split starting technology, including the following steps:

[0039] S1, under the construction condition of only one shaft and one dark excavation section, the shield machine body is connected with the equipment bridge and the trolley part separately;

[0040] S2, divides the origination process into three stages:

[0041] S21, the shield machine mainframe is located underground, the equipment bridge, connecting bridge and trolley are placed on the ground, and are connected by extended pipelines to complete the first stage of shield excavation;

[0042] During the transportation and assembly phase of the S211 segment, each ring of the segment is hoisted using a 45t gantry crane on the well in six times, using the gap between the screw machine and the reaction frame to vertically hoist the segment down to the well for assembly;

[0043] S212, other materials are hoisted and lowered into the well by a 45t gantry crane in the same way as the segment transportation;

[0044] S213: At this stage, pay attention to the assembly quality of the negative ring segments and the reinforcement of the shield tail segments;

[0045] S22, when the tunnel is excavated to a length that can accommodate the length of the connecting bridge and the No. 1 trolley (depending on the specific equipment length, about 38 meters), the equipment bridge, the No. 1 trolley are connected to the shield, and the No. 2 to No. 5 trolleys are temporarily placed on the ground to assemble the -3 ring to +5 ring;

[0046] S221, after the shield enters the tunnel, the positive ring of the section is assembled with 1.2m wide segments, and after the +5 rings are assembled, the tunnel door is sealed;

[0047] S222, two homemade slag buckets are placed on the slag flat plate in the mine, and are pulled by a winch to ensure circular construction. According to the size of the slag bucket and the rear of the reaction frame, the slag bucket needs to be rotated horizontally 90° after lifting to pass through the space behind the reaction frame;

[0048] S223, the transportation of pipe segments is carried out simultaneously with the transportation of slag, and the single piece is hoisted horizontally and transported down the well;

[0049] S224, synchronous grouting slurry is pumped to the shield tail grouting pipe using an extended slurry pipe at the starting well;

[0050] S225, when the tunnel gate is blocked, since the grouting hole is close to the shield tail, during the construction process, in order to ensure that the shield tail is not wrapped and the slurry does not flow into the shield tail, the shield driver monitors the grouting volume and pressure in real time, pushes the shield machine short distance at the right time, and strengthens the injection of grease at the shield tail;

[0051] S23: When the tunnel is excavated to a length that can accommodate the equipment bridge and all trolleys (depending on the specific equipment length, about 82 meters), trolleys 2 to 6 are connected to trolley 1 and enter the normal excavation stage;

[0052] S231, after the +5 ring is advanced, the shield machine screw has completely entered the structure, and the top segment of the negative ring segment can be removed and replaced with Ф609 steel support;

[0053] S232, the middle part of the steel support is supported on the segment by 200H steel, the rear part is welded with steel plate and reaction frame, the front part is connected with the segment by steel plate and segment bolts, each connection position is equipped with triangular steel plate support, and the two side supports are welded with steel bars to form a whole;

[0054] S24, assembly of rings 6 to 28 is completed;

[0055] S241, in this stage, the grouting is also done by using a ground-mounted extended grouting pump to grout into the hole;

[0056] S242, using battery cars to improve safety and work efficiency:

[0057] When discharging slag, the battery car is composed of a machine head plus a slag bucket. After the lower space of the shield machine's screw machine is full of slag, it is pulled to the wellhead and the slag bucket and flat plate are lifted to the ground for vertical transportation of segments and materials. Since there is no double-track beam at this stage, the battery car is used in the tunnel to horizontally pull the single segment to the assembly surface for assembly.

[0058] The present invention changes the shield construction integral starting mode to the semi-ring split starting mode, mainly because there is not enough construction space. Under the condition of only one vertical shaft and dark excavation tunnel, to complete the shield construction, if the integral starting work is adopted, it is necessary to construct a slag well and a hoisting well separately, which increases the construction cost. After changing to the semi-ring split starting mode, the construction space is greatly utilized, the construction period is shortened, the construction cost is reduced, and the construction safety is guaranteed.

[0059] The present invention adopts a three-stage starting method, which is compared with the commonly used two-stage starting method (i.e. canceling the second stage and using a one-stage excavation method. When excavating to about 82 meters, trolley No. 1, connecting bridge and trolleys No. 2 to No. 6 all directly enter the tunnel). First, it can reduce the damage of the segments and improve the assembly efficiency. If the two-stage starting method is adopted, the segments need to be placed on the track for a long time for transportation, which is easy to cause the segments to be damaged, and only one segment can be transported at a time, and the assembly time is too long. With the three-stage starting method, a flatbed trolley can be used to transport the segments in the second stage, and three segments can be transported at one time; second, it can avoid the synchronous grouting pipeline being too long, which leads to the occurrence of pipe blockage, thereby improving the construction efficiency.

[0060] The present invention changes the overall starting mode of shield construction to a split starting mode. This is mainly because there is not enough construction space. Under the condition of only one vertical shaft, wind pavilion group and dark-excavated tunnel, in order to complete the shield starting construction, if the overall starting work is adopted, it is necessary to construct a slag well and a hoisting well separately, which increases the construction cost. After changing to the split starting mode, the construction space is greatly utilized, the construction period is shortened, the construction cost is reduced, and the construction safety is guaranteed. The surrounding environment of Chengdu Metro Line 30 is complex, and there is an existing dark excavation behind the starting shaft. If the overall starting mode is adopted, the dark excavation structure must be completed before it can be implemented. The dark excavation construction process is relatively complicated and the construction period is long. The overall accounting saves about 6 months of construction period, about 4.8 million.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. 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 solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. The technology of split-starting of limited space shield in subway shaft is characterized by: The following steps are involved: S1, under the construction condition of only one shaft and one dark excavation section, the shield machine body is connected with the equipment bridge and the trolley part separately; S2, divides the origination process into three stages: S21, the shield machine mainframe is located underground, the equipment bridge, connecting bridge and trolley are placed on the ground, and are connected by extended pipelines to complete the first stage of shield excavation; S22: When the tunnel is excavated to a length that can accommodate the length of the connecting bridge and the No. 1 trolley, the equipment bridge, the No. 1 trolley and the shield are connected, and the No. 2 to No. 5 trolleys are temporarily placed on the ground; S23: When the tunnel is excavated to a length that can accommodate the equipment bridge and the length of all trolleys, trolleys No. 2 to 6 are connected to trolley No. 1 and the normal excavation stage begins.

2. The subway shaft limited space shield split starting technology according to claim 1 is characterized in that: In step S21, the following steps are also included: S211, segment transportation and assembly stage, each ring of segments is vertically hoisted down the well for assembly by using the gantry crane on the well several times through the gap between the screw machine and the reaction frame; S212, other materials are hoisted and lowered into the well by gantry crane just like the segment transportation; S213, when assembling the negative ring segments, pay attention to the segment assembly quality and the reinforcement of the segments that have come out of the shield tail.

3. The subway shaft limited space shield split starting technology according to claim 1 is characterized in that: In step S22, the following steps are also included: S221, after the shield enters the hole, use the pipe segments with specified width to assemble the ring; S222, use a self-made slag bucket placed on the slag flat plate, and use a winch to pull it to ensure cyclic construction; S223, the transportation of pipe segments is carried out simultaneously with the transportation of slag, and the single piece is hoisted horizontally and transported down the well; S224, synchronous grouting slurry is pumped to the shield tail grouting pipe using an extended slurry pipe at the starting well; S225, when the tunnel gate is blocked, the shield driver monitors the grouting volume and pressure in real time, advances the shield machine a short distance at the right time and strengthens the injection of grease at the shield tail.

4. The subway shaft limited space shield split starting technology according to claim 1 is characterized in that: In step S23, the following steps are also included: S231, remove the top segment of the negative ring and replace it with a steel support; S232, the steel support is connected to the pipe segment and the reaction frame by steel plates and bolts, and triangular steel plate supports and steel bars are welded to form an integral structure.

5. The subway shaft limited space shield split starting technology according to claim 1 is characterized in that: It also includes the use of battery vehicles to improve safety and work efficiency in the subsequent excavation stage. Specifically, when discharging slag, the battery vehicle is composed of a machine head and a slag bucket. After the lower space of the shield machine's screw machine is full of slag, it is pulled to the wellhead and the slag bucket and flat plate are lifted to the ground for vertical transportation of segments and materials. Battery vehicles are used in the tunnel to horizontally pull single segments to the assembly surface for assembly.

6. The subway shaft limited space shield split starting technology according to any one of claims 1 to 5, characterized in that: This technology is suitable for shield tunneling construction scenarios with complex surrounding environments and limited construction space. Through the split starting method, it greatly utilizes the construction space, shortens the construction period, reduces construction costs, and ensures construction safety.

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