Overall launching method of ultra-short launching well TBM (Tunnel Boring Machine)

Abstract

The invention relates to an overall launching method for a TBM of an ultra-short launching shaft. The overall launching method comprises the following steps that firstly, a long subway tunnel is constructed in a segmented mode; step 2, tunnel stepping hole construction; 3, first tunnel shield construction is carried out; step 4, track construction in the first tunnel; 5, a second tunnel TBM is constructed; step 6, hoisting out of the well, deslagging and lowering duct pieces; 7, construction train dispatching and marshalling; and 8, deslagging of the starting well and pipe piece lowering are carried out. The method has the advantages that the hoisting well is used as a temporary starting site, two columns of standard whole-column slag discharging marshalling can be configured, one column can meet the slag discharging amount of one-ring tunneling, the time for one-ring tunneling is only 80 min, ten or more rings can be tunneled every day, and the construction efficiency is remarkably improved; according to the method, the scheme that the original vertical shaft serves as the whole original is adopted, a subway construction project is taken as an example, the equipment transformation cost is saved, the pipeline cost is prolonged by about 23,500 thousand yuan, and the construction period is shortened by 3 months.

Description

Technical Field

[0001] The present invention relates to tunnel construction, and more particularly to an integral launching method for a TBM in an ultra-short launching shaft. Background Art

[0002] In the mechanical tunneling construction of urban subway interval tunnels, when a shield / TBM is launched from a launching shaft, affected by the length of the launching shaft, the conventional method adopts a split launching method. Otherwise, the drift (with the same length as the whole machine of the equipment) needs to be excavated by the mining method long enough to ensure that the whole machine of the mechanical equipment enters the drift to meet the conditions for integral launching. The construction progress of the mining method is slow, the construction cost is high, and the safety risk is great, which is not conducive to on-site construction management; if the excavation length of the drift is reduced and split launching is adopted, the equipment connection pipelines need to be increased, and the local part of the trailing gantry needs to be modified, increasing the costs of equipment pipeline extension and modification, and the construction efficiency of split launching is low. Therefore, under the condition of permission, integral launching should be considered as much as possible. According to the actual situation on site, a construction method for integral launching of a TBM in an ultra-short launching shaft has been developed in a certain subway construction.

[0003] In the published patent application documents, for example, Chinese Patent Application No. 201910142756.2 discloses an invention named "TBM Launching Shaft Shaft Construction Method", including: construction of the shaft lock girder, construction of the shaft body, and construction of the shaft lining. The TBM launching shaft shaft construction method in the present invention improves the excavation construction efficiency and safety of the TBM launching shaft, reduces the construction cost, and improves the construction feasibility by designing three major steps of construction of the shaft lock girder, construction of the shaft body, and construction of the shaft lining.

[0004] Again, for example, Chinese Patent Application No. 202310090837.9 discloses a shield launching method, which includes the following steps: strengthening the launching end; obtaining the geological type at the bottom of the shield launching shaft and the preset model of the shield machine, and determining the settlement depth of the launching support according to the geological type and the preset model; installing the launching support at the bottom of the shield launching shaft according to the settlement depth; assembling and debugging the shield machine on the launching support; installing a reaction frame in the shield launching shaft; installing a negative ring segment between the shield machine and the reaction frame; chiseling the portal of the shield receiving shaft to form a launching hole; and tunneling the shield machine through the launching hole. This shield launching method makes the height of the launching support conform to the actual situation on site, thereby reducing the vertical offset of the shield machine, and further reducing the deviation between the shield axis and the tunnel axis.

[0005] For another example, Chinese invention patent application No. 202311000512.3 discloses a micro-TBM launching method, comprising the following steps: 1) reinforcing the rock mass of the launching section profile; 2) installing a front-pull reaction frame; and 3) launching the micro-TBM. This method has the advantages of a simple structure and easy installation. By welding a steel frame to the micro-TBM shield and transmitting the launching reaction force to the rock mass reinforced by grouting with a small guide tube via anchor rods, the traditional back-push fixed reaction frame is transformed into a front-pull movable reaction system. This simple and reliable structure, easy method, low space requirements, and wide applicability are of great significance for launching micro-TBMs in projects without launching holes or wells, reducing construction time and economic costs.

[0006] None of the above invention patent applications has solved the construction method of the overall launching of TBM in the launching well with an ultra-short distance. Summary of the Invention

[0007] The present invention aims to solve the problems existing in the prior art and provides a TBM integrated launching method for an ultra-short launching well.

[0008] The TBM integrated launching method for an ultra-short launching well comprises the following steps: Step 1: Segmented construction of long subway tunnels; Step 2: Tunnel stepping hole construction; Step 3: Shield construction of the first tunnel; Step 4: Track construction in the first tunnel; Step 5: TBM construction of the second tunnel; Step 6: hoisting out the well, removing the slag and lowering the pipe segments; Step 7: Construction train dispatching and marshaling; Step 8: Remove slag from the starting well and install pipe segments.

[0009] Furthermore, in step 1, the long subway tunnel is constructed in sections, specifically including: For long and large tunnels in subway sections, it is usually necessary to set up a starting shaft in the middle. For this purpose, the long and large tunnel is divided into two. First, the relatively shorter first tunnel is constructed and penetrated, and then the other longer second tunnel is excavated. The second tunnel excavation machinery and equipment are stored in the penetrated first tunnel. Auxiliary operations such as slag removal and material feeding of the second tunnel are carried out at the hoisting shaft of the penetrated first tunnel to complete the overall starting goal of the second tunnel mechanical excavation, so as to avoid or reduce the excavation of step holes in the second tunnel.

[0010] Furthermore, step 2 tunnel stepping hole construction specifically includes: A step-through hole at one end of the first tunnel was excavated using the mining method in the ultra-short launch shaft. A guide platform was constructed at the bottom of the first tunnel step-through hole. Guide platform reinforcement was first tied, and guide rail embedded parts were installed on the structural reinforcement. The embedded parts were spaced 1 to 1.5 meters apart. The guide rails were fixed to the embedded parts and firmly secured by welding. Formwork was then erected in sections, and concrete was poured. The concrete strength grade was C35. The secondary structure lining work was carried out on the expanded end of the starting tunnel using a disc-type full-house red scaffold. First, the secondary structure reinforcement of the expanded end was tied, and the reaction frame was embedded and the embedded parts were installed. Then, the pre-bent arc-shaped steel arch frame was installed on the support, and the composite steel formwork was installed on the arch frame, and C45 concrete was poured. The length of the stepping tunnel is 40~50m (including the starting tunnel) to meet the length requirement of the shield equipment going down the shaft. The cross-section of the stepping tunnel of the first tunnel adopts a horseshoe-shaped cross-section and is operated by blasting excavation or breaker hammer excavation. A starting tunnel is set at the front end of the stepping tunnel. The starting tunnel adopts a circular cross-section and is 9m long. The reaction frame for the starting of the shield is installed at the expanded end of the starting tunnel. The reaction frame is divided into 5 parts, namely the upper and lower beams, left and right columns and diagonal braces. First, the lower beam is positioned, and the left and right columns are connected to the lower beam. Then the upper beam and diagonal brace are connected. After all the bolts are tightened, the back support is finally installed. The back support is firmly welded to the embedded steel plate at the expanded end. The reaction frame is installed at the tail position of the shield. The reaction frame is vertical to the shield body. The 0-ring segment is in contact with the reaction frame and is firmly fixed to the reaction frame with segment bolts. The gap between the 0-ring segment reaction frame and the tunnel wall is sealed with red bricks to ensure that the synchronous grouting and secondary grouting are not Leakage; the mining method is used to excavate the TBM side step hole of the second tunnel on the other side of the ultra-short starting shaft. The step hole adopts a circular cross-section and the length of the step hole is 12~14m to meet the needs of TBM step-by-step assembly of pipe segments; after the excavation of the step hole in the first tunnel is completed, the guide platform and the secondary lining structure of the starting hole are constructed to provide space for the shield equipment to be assembled and excavated; after the construction of the TBM step hole of the second tunnel is completed, only the guide platform is constructed, and the secondary lining structure of the step hole is formed by assembling pipe segments, omitting the secondary lining cast-in-place concrete operation. At the start, the reaction frame is installed at the end wall of the starting shaft and the 0-ring pipe segment is assembled. The installation method is the same as above, which not only omits the installation of the negative ring pipe segment but also avoids the removal of the negative ring pipe segment.

[0011] Furthermore, step 3 of the shield construction of the first tunnel specifically includes: After the construction of the step-in tunnel was completed, the shield method was adopted for the first tunnel side. The main machine, connecting bridge, 1~4# trolleys were first lowered into the well for assembly, and the 5# and 6# trolleys were temporarily placed on the ground. This split starting method omitted equipment modification and pipeline extension. Before the 5# and 6# trolleys were lowered into the well for assembly, a sewage collection well was added to the starting well, and a sewage pump was installed for sewage treatment. The cable was hung on the wall of the tunnel with extra length. When the conditions for the whole machine to be in place were met, the 5# and 6# trolleys were hoisted into the well for assembly, and the shield entered the normal excavation state. The 55T gantry crane equipment in the starting well was used for slag discharge and feeding.

[0012] Furthermore, step 4 of the first tunnel track construction specifically includes: After the first tunnel is bored through, the second tunnel boring equipment is lowered into the well for assembly, debugging and excavation. Due to the space limitation of the starting well, after the equipment is lowered into the well, except for pea gravel which can be transported to the bottom of the starting well by pipeline, other hoisting operations cannot be carried out in the starting well. The early slag discharge and material feeding of the second tunnel all need to be assisted by the hoisting out well after the first tunnel is bored. Due to the short length of the hoisting out well and limited space, it is necessary to lay a 150-250m long double-track P43 rail transport line near the hoisting out well in the first tunnel, and install 4 sets of P43 single-opening turnouts to form two sets of double-track shunting lines. The length of each line is not less than the length of a whole train. The shortest distance between the two lines is not less than the length of one dump truck plus an electric car. The electric car is used to tow or push back and forth the horizontal transportation of slag trucks, pipe segment flatbed trucks, etc. from the second tunnel for re-marshaling.

[0013] Step 5: TBM construction of the second tunnel, specifically including: After the first tunnel was bored through, the TBM equipment for the second tunnel was lowered into the well for assembly. The assembly procedure was the same as usual. After lowering, the supporting trolleys were placed inside the first tunnel, and the shield was pushed horizontally into the step-in tunnel. The reaction frame backrest was hoisted as a whole using a slag gantry crane. The backrest was installed on the side end wall of the TBM tunnel in the starting well, closely fitting against the end wall. The horizontal and vertical alignment of the reaction frame backrest was adjusted. The left and right columns were firmly welded to the embedded parts of the starting well floor. Two diagonal braces were added to the top of the columns and fixed to the side walls on both sides. Three φ609 steel pipe diagonal braces were added to the left and right sides of the middle of the columns. The steel pipe diagonal braces were firmly welded to the backrest and embedded parts of the floor. The TBM's posture was measured and verified, with the shield perpendicular to the reaction frame backrest plane. TBM equipment pipelines were connected, the TBM equipment was debugged, and a segment assembly machine was used to assemble the zero-ring segment at the shield tail. The zero-ring segment was tightly attached to the reaction frame backrest plane and secured to the reaction frame with segment bolts. The gap between the segment reaction frame and the tunnel wall was sealed with red bricks, and the remaining gaps were sealed with hand grease to prevent slurry leakage during pea gravel filling and grouting. TBM slag discharge and feeding were carried out using conventional train marshaling, transported horizontally through the first tunnel, and hoisted out and lowered into the first tunnel's hoistway.

[0014] Furthermore, for the erection of the segment of Ring 0 during the TBM tunneling construction, "L"-shaped angle steels are welded on the shield tail to stabilize the segments. After the segments are withdrawn from the shield tail, the lifting holes are opened, and positive and negative threaded steel sleeves are promptly used to support the segments. After the segments are withdrawn from the shield tail, pea gravel is blown and filled. Before blowing and filling the pea gravel, the support sleeves are removed first. A water stop ring hoop is provided every 10 - 15 rings. The water stop ring hoop is filled with a double-fluid slurry of cement and water glass, and the remaining part is backfilled with cement slurry.

[0015] Furthermore, the slag removal and segment lowering at the hoisting shaft described in Step 6 specifically include: A crawler crane, a forklift, and a muck truck are configured at the first tunnel hoisting shaft for temporary slag removal and segment lowering during the transition. The crawler crane is used for the vertical transportation of slag removal and feeding in the second tunnel, for the loading and unloading of pea gravel tanks, slag buckets, segments, and turnover materials. During horizontal transportation scheduling, the whole train formation is placed in one of the two double tracks, parked on the main line between two turnouts. The battery car pulls each vehicle back and forth through the two turnouts to the hoisting shaft of the first tunnel for material loading and unloading. The full muck bucket is hoisted and loaded onto the truck and transported to the TBM launching site for unloading and dumping. At the launching shaft, it is then unloaded into the muck pit by a gantry crane, and the empty bucket is transported back to the temporary launching site of the first tunnel hoisting shaft for lowering into the well; the empty pea gravel tank is re-grouped and horizontally transported to the launching shaft, and pea gravel is loaded at the launching shaft using a vertical pipeline; the segments are stored in the hoisting shaft site, transported to the crane position by a forklift, and hoisted and placed into the truck at the hoisting shaft for loading.

[0016] Furthermore, the train transportation formation described in Step 7 specifically includes: Step 7.1 Segment car formation: Under normal operation of the mine car train, its formation is a battery car + 4 muck cars + 1 pea gravel car + 2 segment cars. The battery car pulls the entire train of mine cars and horizontally transports and parks the train full of muck on the main line between the second set of double-track two turnouts. Use iron shoes to lock the wheels of the train to be transferred, remove the interlock between the battery car and the muck cars, the battery car passes through the two turnouts of the second double track, transports to the position of the second segment car, connects to the second segment car, and removes the interlock between the second segment car and the first segment car. The battery car pulls the second segment car through the second set of double-track turnouts and the second double track, pushes the second segment car to the position of the first tunnel hoist-out shaft, uses a crawler crane to lift and place the segment on the second segment car, the battery car pulls the second segment car with a heavy load through the second double track, enters the main line between the first set of double-track two turnouts and parks, and locks it with iron shoes, waiting for reformation; remove the connection between the battery car and the second segment car, the battery car horizontally transports through the first set of double-track turnouts and the first double track, enters the main line train parking position of the second double track, connects to the first segment car, removes the interlock between the first segment car and the pea gravel car, the battery car pulls the first segment car through the second set of double-track turnouts and the second double track, pushes the first segment car to the hoist-out shaft, uses a crawler crane to lift and place the segment on the first segment car, the battery car pulls the first segment car with a heavy load through the second double track, parks between the first set of double-track turnouts and the second set of double-track turnouts and locks it, removes the interlock between the battery car and the first segment car, the battery car enters the main line of the first double track through the first double track, reaches the position of the second segment car and connects to it, the battery car pushes the second segment car to the position of the first segment car and connects to the first segment car, the battery car pulls the second segment car and the first segment car into the main line of the first set of double tracks and parks, and locks it with iron shoes, waiting for reformation again; Step 7.2 Pea gravel car formation: After the reformation of the segment cars is completed, the pea gravel car formation is carried out. The pea gravel cars are formed with empty cars. When the entire train is transported to the starting shaft, they are loaded through the pea gravel pipeline. After the 2 segment cars are formed with a heavy load, the battery car returns to the position of the pea gravel cars and connects to them. Remove the interlock between the pea gravel cars and the muck cars, the battery car pulls the pea gravel cars to park between the first set of double-track turnouts and the second set of double-track turnouts, and locks them with iron shoes. Remove the interlock between the battery car and the pea gravel cars, the battery car passes through the first set of double-track turnouts and the first double track, enters the main line of the first set of double tracks, and connects to the segment cars. Push the segment cars to the position of the pea gravel cars and connect to them, pull the 2 segment cars + 1 pea gravel car to the main line position of the first set of double tracks and park, and lock them with iron shoes, waiting for the muck to be unloaded and the empty cars to be reformed again; Step 7.3 Muck car formation: As described above, the battery car returns to the position of the fourth muck truck again, connects to the muck truck, removes the interlock between the fourth and the third muck trucks, the battery car drags the fourth fully-loaded muck truck, and transports the fourth muck truck through the second set of double-track turnouts and the second double track to the lifting shaft. Use a crawler crane to lift the slag bucket onto the transport vehicle, fix it firmly, transport it by vehicle to the launching shaft, and use a gantry crane to lift and unload the slag bucket into the muck pond. After unloading the muck, return the empty slag bucket to the lifting shaft, use a crawler crane to lift the slag bucket onto the fourth muck truck, the battery car transports the fourth empty muck truck and parks it between the first set of double-track turnouts and the second set of double-track turnouts, removes the interlock between the battery car and the empty muck truck, and locks the empty muck truck with an iron shoe. The battery car enters the main line of the first double track through the first set of double-track turnouts and the first double track, reaches the position of the segment car, and connects to the new formation. Push the newly formed train of the gravel car and 2 segment cars to the parking position of the empty fourth muck truck and connect to it. The battery car transports the new formation back to the main line of the first set of double tracks again and locks it with an iron shoe. And so on, push the other 3 muck trucks to the lifting shaft for unloading in turn and carry out reformation to form a whole train formation. The battery car returns to the initial state, and pushes the whole train formation of battery car + 4 muck trucks + 1 gravel car + 2 segment cars to the launching shaft, park the gravel car under the vertical transportation pipeline of the gravel in the launching shaft, and lower the gravel into the gravel hopper. After filling the gravel, the battery car continues to push the whole train formation to the TBM tunneling area for use.

[0017] Further, for the muck discharging and segment lowering at the launching shaft in step 8: The cement slurry used for grouting at the initial stage is mixed in the mixing plant installed in the launching shaft site, and the cement slurry is directly pumped into the segment lifting hole by a piston pump to grout and consolidate the gravel behind the segments. After the TBM of the second tunnel enters the second tunnel, all the muck discharging and feeding in the second tunnel are carried out at the launching shaft, and the normal tunneling state is restored. At this time, the double-track railway at the lifting shaft in the first tunnel can be removed. Continuously with the TBM tunneling, as the tunneling distance of the second tunnel increases, in order to improve the TBM tunneling efficiency, double-track railways can be set within the range of 140 - 160 m of the launching shaft. Using the launching shaft for muck discharging and feeding, the train formation consists of 1 battery car, 4 muck trucks, 1 gravel car, and 2 segment cars, and is transported in 2 train formations. Both muck discharging and segment lowering adopt vertical transportation by gantry crane. The gravel is horizontally transported by hopper and belt conveyor and vertically transported through the pipeline into the gravel hopper. The grouting material uses bagged cement, and a cement slurry mixing tank is added to the rear support trolley to mix the cement slurry on site, and the piston pump injects it behind the segments to consolidate the gravel.

[0018] Further, the gravel filling and grouting backfilling are carried out in a timely manner. When the segment exits the shield tail, the gravel is filled in by blowing in a timely manner, and the grouting time shall not lag behind 10 - 15 rings to ensure the stable attitude of the segment.

[0019] Furthermore, the grouting pressure is 0.3~0.8 MPa.

[0020] Compared with similar construction methods in the art, the ultra-short launch well TBM integrated launch method of the present invention has the following superior technical effects: 1. The ultra-short launching shaft TBM integrated launching method of the present invention utilizes a hoisting shaft as a temporary launching site. It can be equipped with two standard full-train slag-discharging trains. One train can meet the slag discharge requirements for one excavation ring, which takes approximately 80 minutes. More than 10 excavation rings can be excavated per day. If the split launching scheme is directly based on the launching shaft, full-train slag-discharging trains cannot be configured, and only 1 to 2 excavation rings can be excavated per day, resulting in low excavation efficiency.

[0021] 2. The ultra-short TBM launching method of the present invention requires a split launching scheme in the launching shaft. It is necessary to first excavate a 50m launching pilot tunnel using the mining method, which takes nearly 2 months. If TBM excavation is used, it only takes 4 to 5 days. After the TBM tunnel is penetrated, the launching pilot tunnel also needs a secondary lining operation with cast-in-place concrete, which greatly increases the pilot tunnel excavation cost, construction period and safety risks of the mining method.

[0022] 3. The ultra-short launching shaft TBM overall launching method described in the present invention uses the launching shaft as a split launching scheme. In this case, the TBM needs to undergo equipment modification, the temporary belt slag outlet is converted to the 5# trolley, and a temporary slag hopper is processed. Taking a subway construction project as an example, the cost of increasing the split launching equipment modification is about 1.8 million yuan.

[0023] 4. The ultra-short launching shaft TBM integrated launching method described in the present invention utilizes a launching shaft for split launching, requiring an extension pipeline of more than 100 m between trolleys 5 and 6. Taking a subway construction project as an example, the cost of the split launching pipeline is approximately RMB 550,000. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flow chart of the TBM integrated launching method for an ultra-short launching well according to the present invention. DETAILED DESCRIPTION

[0025] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other unless there is a conflict. Example

[0026] like Figure 1 As shown, the TBM integrated launching method for an ultra-short launching well of the present invention comprises the following steps: Step 1: Segmented construction of long subway tunnels; Step 2: Tunnel stepping hole construction; Step 3: Shield construction of the first tunnel; Step 4: Track construction in the first tunnel; Step 5: TBM construction of the second tunnel; Step 6: hoisting out the well, removing the slag and lowering the pipe segments; Step 7: Construction train dispatching and marshaling; Step 8: Remove slag from the starting well and install pipe segments.

[0027] As a specific step of the present invention, the segmented construction of the long subway tunnel described in step 1 specifically includes: For long and large tunnels in subway sections, it is usually necessary to set up a starting shaft in the middle. For this purpose, the long and large tunnel is divided into two. First, the relatively shorter first tunnel is constructed and penetrated, and then the other longer second tunnel is excavated. The second tunnel excavation machinery and equipment are stored in the penetrated first tunnel. Auxiliary operations such as slag removal and material feeding of the second tunnel are carried out at the hoisting shaft of the penetrated first tunnel to complete the overall starting goal of the second tunnel mechanical excavation, so as to avoid or reduce the excavation of step holes in the second tunnel.

[0028] As a specific step of the present invention, the tunnel stepping hole construction described in step 2 specifically includes: A step-through hole at one end of the first tunnel was excavated using the mining method in the ultra-short launch shaft. A guide platform was constructed at the bottom of the first tunnel step-through hole. Guide platform reinforcement was first tied, and guide rail embedded parts were installed on the structural reinforcement. The embedded parts were spaced 1 to 1.5 meters apart. The guide rails were fixed to the embedded parts and firmly secured by welding. Formwork was then erected in sections, and concrete was poured. The concrete strength grade was C35. The secondary structure lining work was carried out on the expanded end of the starting tunnel using a disc-type full-house red scaffold. First, the secondary structure reinforcement of the expanded end was tied, and the reaction frame was embedded and the embedded parts were installed. Then, the pre-bent arc-shaped steel arch frame was installed on the support, and the composite steel formwork was installed on the arch frame, and C45 concrete was poured. The length of the advancing tunnel is 40 - 50 m (including the launching chamber) to meet the requirement of the tunneling length for the shield equipment to enter the well. The cross-section of the advancing tunnel of the first tunnel is a horseshoe-shaped cross-section, and the operation is carried out by blasting excavation or hydraulic breaker excavation. An launching shaft is set at the front end of the advancing tunnel. The launching chamber has a circular cross-section with a length of 9 m. The reaction frame for shield launching is installed at the enlarged end of the launching chamber. The reaction frame is divided into 5 parts, namely the upper and lower crossbeams, the left and right columns and the diagonal braces. First, the lower crossbeam is positioned, and the left and right columns are connected to the lower crossbeam, then the upper crossbeam and the diagonal braces are connected. After all the bolts are tightened, the back brace is installed finally. The back brace is welded firmly to the embedded steel plate at the enlarged end. The reaction frame is installed at the position of the shield tail, and the reaction frame is perpendicular to the shield body. The 0-ring segment abuts against the reaction frame and is fixed firmly to the reaction frame with segment bolts; the gap between the 0-ring segment reaction frame and the tunnel wall is blocked by laying red bricks to ensure that the primary grouting and secondary grouting do not leak; on the other side of the ultra-short launching shaft, the advancing tunnel of the TBM side of the second tunnel is excavated by the drift method. The advancing tunnel has a circular cross-section with a length of 12 - 14 m to meet the need for TBM to change steps and assemble segments; after the excavation of the advancing tunnel in the first tunnel is completed, the guide platform and the secondary lining structure of the launching chamber are constructed to provide space for the shield equipment to enter the well for assembly and start tunneling; after the construction of the advancing tunnel of the second tunnel TBM is completed, only the guide platform is constructed. The secondary lining structure of the advancing tunnel is formed by segment assembly, omitting the cast-in-place concrete operation of the secondary lining. When starting, the reaction frame is installed at the end wall of the launching shaft, and the 0-ring segment is assembled. The installation method is the same as above, omitting the installation of the negative ring segments and avoiding the removal of the negative ring segments.

[0029] As a specific step of the present invention, the shield construction of the first tunnel described in step 3 specifically includes: After the construction of the advancing tunnel is completed, the shield method is used for construction on the first tunnel side. The main machine, connection bridge, and 1 - 4# trolleys are first lowered into the well for assembly, and the 5# and 6# trolleys are temporarily placed on the ground. This split launching method omits equipment modification and extension of pipeline. Before the 5# and 6# trolleys are lowered into the well for assembly, a sewage sump is added in the launching shaft, and a sewage pump is installed for sewage treatment; the cables are suspended on the tunnel wall with a surplus length. When the conditions for the whole machine to be in place are met, the 5# and 6# trolleys are respectively hoisted into the well for assembly, and the shield enters the normal tunneling state. The muck removal and feeding are both carried out by the 55T gantry crane equipment in the launching shaft.

[0030] As a specific step of the present invention, the track construction in the first tunnel described in step 4 specifically includes: After the first tunnel is bored through, the second tunnel boring equipment is lowered into the shaft for assembly, commissioning, and boring. Due to the limited space in the launch shaft, after the equipment is lowered into the shaft, except for the pea gravel that can be transported to the bottom of the launch shaft through pipelines, other hoisting operations cannot be carried out in the launch shaft. For the initial mucking and feeding of the second tunnel, the hoist-out shaft after the first tunnel is bored through needs to be utilized for auxiliary operations. Since the length of the hoist-out shaft is short and the space is limited, a double-track P43 track transportation line with a length of 150 - 250 m needs to be laid near the hoist-out shaft in the first tunnel, and 4 sets of P43 single turnout switches are installed to form two sets of double-track transfer lines. The length of each line is not less than the length of a whole train formation, and the shortest distance between the two lines is not less than the length of 1 slag bucket car plus a battery car, which is used for the horizontal transportation of the muck trucks and segment flatbed trucks of the second tunnel by means of battery car towing or pushing back and forth for reformation.

[0031] As a specific step of the present invention, the TBM construction of the second tunnel described in step 5 specifically includes: After the shield tunnel of the first tunnel is bored through, the TBM equipment of the second tunnel is lowered into the shaft for assembly. The assembly procedure for lowering into the shaft is the same as the conventional method. After being lowered into the shaft, the trailing gantries are all placed in the first tunnel, and the shield body is pushed flat into the advancing tunnel. Use the mucking gantry crane to hoist the reaction frame backrest as a whole. The backrest is installed at the side wall of the TBM tunnel at the launch shaft, close to the side wall, and adjust the horizontal and verticality of the reaction frame backrest. The left and right columns are firmly welded to the embedded parts on the bottom plate of the launch shaft, and diagonal braces are added at the top of the columns, fixed to the side walls on both sides. Three φ609 steel pipe diagonal braces with a diameter of each are added to the left and right of the middle of the columns. The steel pipe diagonal braces are firmly welded to the backrest and the embedded parts on the bottom plate. Measure and review the TBM attitude. The shield body is perpendicular to the plane of the reaction frame backrest. Connect the TBM equipment pipelines, commission the TBM equipment, use the segment erector to assemble 0-ring segments at the shield tail. The 0-ring segments are close to the plane of the reaction frame backrest and are fixed to the reaction frame with segment bolts. The gaps between the segments and the tunnel wall at the reaction frame are blocked with red bricks, and the remaining gaps are sealed by hand-applying grease to ensure that no slurry leakage occurs during the blowing of pea gravel and grouting. The mucking and feeding of the TBM adopt the conventional train formation method, and the horizontal transportation passes through the first tunnel, being hoisted out and lowered into the shaft at the hoist-out shaft of the first tunnel. The TBM boring construction and the assembly of 0-ring segments are carried out. "L"-shaped angle steels are welded on the shield tail to stabilize the segments. After the segments are withdrawn from the shield tail, the lifting holes are opened, and the segments are supported in time with positive and negative thread steel sleeves. After the segments are withdrawn from the shield tail, the pea gravel is blown. Before blowing the pea gravel, the support sleeves are removed first. A water stop ring hoop is set every 10 - 15 rings. The water stop ring hoop adopts the injection of cement-sodium silicate double-fluid slurry, and the rest is backfilled with cement slurry.

[0032] As a specific step of the present invention, the mucking and segment lowering at the hoist-out shaft described in step 6 specifically includes: A crawler crane, a forklift and a muck truck are arranged at the first tunnel hoisting shaft for temporary muck discharging and segment lowering during the transition. The crawler crane is used for the vertical transportation of muck discharging and feeding in the second tunnel, and is used for loading and unloading the pea gravel tank, muck bucket, segments and turnover materials. During the horizontal transportation scheduling, the whole train formation is placed in one of the two double tracks, parked on the main line between the two turnouts. The battery car shuttles back and forth through the two turnouts to tow each vehicle to the first tunnel hoisting shaft for material loading and unloading. The full muck bucket is hoisted and loaded onto the truck and transported to the TBM launching yard for unloading. At the launching shaft, the muck is unloaded into the muck pit by a gantry crane, and the empty bucket is then transferred to the temporary launching yard underground of the first tunnel hoisting shaft; the empty pea gravel tank is reorganized and horizontally transported to the launching shaft, and pea gravel is loaded at the launching shaft using a vertical pipeline; the segments are stored in the hoisting shaft site, transferred to the crane position by a forklift, and the segments are hoisted and placed into the truck at the hoisting shaft.

[0033] As a specific step of the present invention, the train transportation formation in step 7 includes the following steps: Step 7.1 Segment car formation: Under normal operation of the ore car train, its formation is a battery car + 4 muck cars + 1 pea gravel car + 2 segment cars. The battery car pulls the whole train formation of ore cars, horizontally transports and parks the train full of muck on the main line between the two turnouts of the second double track. The wheels of the train to be transferred are locked with iron shoes, the interlock between the battery car and the muck car is removed. The battery car passes through the two turnouts of the second double track, transports to the second segment car, connects to the second segment car, removes the interlock between the second segment car and the first segment car. The battery car pulls the second segment car through the second double track turnouts and the second double track, pushes the second segment car to the position of the first tunnel hoisting shaft, and the segment is hoisted and placed on the second segment car by a crawler crane. The battery car pulls the second segment car with a heavy load through the second double track, enters the main line between the two turnouts of the first double track and parks, and is locked with iron shoes, waiting for reorganization; the connection between the battery car and the second segment car is removed, the battery car horizontally transports through the first double track turnouts and the first double track, enters the main line train parking position of the second double track, connects to the first segment car, removes the interlock between the first segment car and the pea gravel car. The battery car pulls the first segment car through the second double track turnouts and the second double track, pushes the first segment car to the hoisting shaft, and the segment is hoisted and placed on the first segment car by a crawler crane. The battery car pulls the first segment car with a heavy load through the second double track, parks between the first double track turnout and the second double track turnout and locks it, removes the interlock between the battery car and the first segment car. The battery car enters the first double track main line through the first double track, reaches the position of the second segment car, and connects to it. The battery car pushes the second segment car to the position of the first segment car and connects to the first segment car. The battery car pulls the second segment car and the first segment car into the main line of the first double track and parks, and is locked with iron shoes, waiting for reorganization again; Step 7.2 Pea Gravel Cart Assembly: After the segment cars are re-formed, the bean-gravel cars are formed. The bean-gravel cars are formed with empty cars. When the entire train is transported to the starting well, they are loaded with bean-gravel pipes. After the two segment cars are reloaded, the battery car returns to the bean-gravel car position and is connected to the bean-gravel car. The chain between the bean-gravel car and the muck car is removed. The battery car pulls the bean-gravel car to the position between the first set of double-track switches and the second set of double-track switches and parks, and locks it with iron shoes. The chain between the battery car and the bean-gravel car is removed. The battery car passes through the first set of double-track switches and the first double track and enters the main line of the first set of double tracks, connects to the segment car, pushes the segment car to the bean-gravel car position, and connects to the bean-gravel car, pulling the two segment cars + 1 bean-gravel car to the main line position of the first set of double tracks and parks, and locks it with iron shoes. After waiting for the muck car to unload, the empty cars are re-formed. Step 7.3: Muck truck formation: As above, the battery car returns to the position of the fourth muck car again, connects to the muck car, removes the chain between the fourth muck car and the third muck car, and the battery car tows the fourth fully loaded muck car, and transports the fourth muck car through the second set of double-track switches and the second double-track top to the hoisting shaft, uses a crawler crane to lift the muck bucket onto the car transporter, fixes it firmly, transports the car to the starting shaft, and uses a gantry crane to unload the muck bucket into the muck pool. After unloading the muck, the empty muck bucket is transported back to the hoisting shaft, and is lifted and placed on the fourth muck car by a crawler crane. The battery car tows the fourth empty muck car and parks it between the first set of double-track switches and the second set of double-track switches, removes the chain between the battery car and the empty muck car, and locks the empty muck car with an iron shoe. The battery car passes through the first set of double-track switches and the first double track, enters the main line of the first double track, reaches the segment car position, and connects to the new train. The pea gravel car and two segment cars are pushed to the parking position of the empty fourth muck car and connected to it. The battery car tows the new train back to the main line of the first double-track group and locks it with iron shoes. Similarly, the other three muck cars are pushed to the hoisting shaft for unloading and re-grouped to form a complete train. The battery car returns to its initial state and pushes the entire train consisting of the battery car + four muck cars + one pea gravel car + two segment cars to the starting shaft. The pea gravel car is parked under the vertical pea gravel transport pipeline in the starting shaft and the pea gravel is lowered into the pea gravel hopper. After the pea gravel is filled, the battery car continues to push the entire train to the TBM excavation area for use.

[0034] Furthermore, the slag removal and segment placement in the starting well in step 8 specifically include: The cement slurry used for grouting in the initial stage is mixed by a mixing station installed in the starting well site, and the cement slurry is directly pumped into the segment hoisting hole with a plunger pump, and pea gravel is grouting and consolidated behind the segment. After the TBM excavation of the second tunnel meets the requirements of the entire TBM entering the second tunnel, the slag discharge and feeding of the second tunnel are all carried out in the starting well, and the normal excavation state is restored. At this time, the double-track track at the hoisting well in the first tunnel can be dismantled. As TBM excavation continued, and as the excavation distance of the second tunnel increased, to improve TBM excavation efficiency, a double-track track was installed within the 140-160m range of the launch shaft. Mud discharge and material loading were carried out using the launch shaft. The train consisted of one battery car, four slag trucks, one pea gravel truck, and two segment trucks, transported in two trains. Slag discharge and segment placement were both transported vertically by gantry cranes. Pea gravel was transported horizontally by hoppers, conveyors, and vertically by pipelines into the pea gravel hopper. Bags of cement were used for grouting. A cement slurry mixing tank was added to the rear trolley. Cement slurry was mixed on-site and injected behind the segments with a plunger pump to consolidate the pea gravel. Pea gravel backfill and grouting were carried out in a timely manner. Pea gravel was blown in immediately after the segments emerged from the shield tail. Grouting should not be delayed by more than 10-15 cycles to ensure segment stability. Grouting pressure was 0.3-0.8 MPa.

[0035] The present invention is not limited to the above-mentioned embodiments. Any modification, improvement, or substitution that can be conceived by those skilled in the art without departing from the essential content of the present invention shall fall within the protection scope of the present invention.

Claims

1. An overall launching method for a super-short launching shaft TBM, the overall launching method for the super-short launching shaft TBM includes the following steps: Step 1, segmental construction of a long subway tunnel; Step 2, construction of the tunnel's advancing hole; Step 3, shield construction of the first tunnel; Step 4, track construction in the first tunnel; Step 5, TBM construction of the second tunnel; Step 6, mucking out and lowering segment linings at the hoisting shaft; Step 7, marshalling of construction trains for transfer; Step 8, mucking out and lowering segment linings at the launching shaft.

2. According to the overall launching method for the super-short launching shaft TBM described in claim 1, the segmental construction of the long subway tunnel in Step 1 specifically includes: For a long subway tunnel section, an intermediate launching shaft is usually required in the middle, dividing the long tunnel into two parts. First, construct and penetrate one relatively shorter first tunnel, and then carry out the excavation of the other longer second tunnel. The tunneling machinery and equipment for the second tunnel are stored in the already penetrated first tunnel. Auxiliary operations such as mucking out and feeding materials for mechanical excavation of the second tunnel are carried out at the hoisting shaft of the already penetrated first tunnel to achieve the goal of the overall launching of mechanical excavation of the second tunnel, so as to avoid or reduce the advancing hole excavation of the second tunnel.

3. According to the overall launching method for the super-short launching shaft TBM described in claim 1, the construction of the tunnel's advancing hole in Step 2 specifically includes the following steps: Step 3.1 Use the drift method to excavate the advancing hole at one end of the first tunnel in the super-short launching shaft. Conduct bench construction at the bottom of the advancing hole of the first tunnel. First, bind the bench reinforcement, install the guide rail embedded parts on the structural reinforcement, fix the guide rail on the embedded parts, and firmly fix it by welding. Erect formwork in sections and pour concrete; Step 3.2 Use a full hall of disk locks type scaffolding for the secondary structure lining operation at the enlarged end of the launching hole. First, bind the secondary structure reinforcement at the enlarged end and embed the reaction frame installation embedded parts. Install a pre-bent arc steel arch frame on the support, then install a combined steel formwork on the arch frame, and pour concrete; Step 3.3 The length of the first tunneling advance hole including the starting hole is 40 - 50 m to meet the requirements of the tunneling length of the shield equipment when it is lowered into the shaft. The cross-section of the first tunneling advance hole is a horseshoe-shaped cross-section, and the operation is carried out by blasting excavation or hydraulic breaker excavation. A starting hole is set at the front end of the tunneling advance hole. The starting hole has a circular cross-section with a length of 9 m. The reaction frame for shield starting is installed at the enlarged end of the starting hole. The reaction frame is divided into 5 parts, namely the upper and lower crossbeams, the left and right columns, and the diagonal braces. First, the lower crossbeam is positioned, and the left and right columns are connected to the lower crossbeam. Then, the upper crossbeam and the diagonal braces are connected. After all the bolts are tightened, the back brace is installed finally, and the back brace is welded firmly to the embedded steel plate at the enlarged end. The reaction frame is installed at the position of the shield tail. The reaction frame is perpendicular to the shield body. The 0-ring segment abuts against the reaction frame and is fixed firmly to the reaction frame with segment bolts. The gap between the position of the 0-ring segment reaction frame and the tunnel wall is blocked with red bricks to ensure that the synchronous grouting and secondary grouting do not leak. On the other side of the ultra-short starting shaft, the mining method is used to excavate the TBM side tunneling advance hole of the second tunnel. The tunneling advance hole has a circular cross-section with a length of 12 - 14 m to meet the needs of TBM step-changing segment assembly. After the excavation of the tunneling advance hole in the first tunnel is completed, the guide platform and the secondary lining structure of the starting hole are constructed to provide space for the assembly and starting tunneling of the shield equipment when it is lowered into the shaft. After the construction of the TBM tunneling advance hole in the second tunnel is completed, only the guide platform is constructed. The secondary lining structure of the tunneling advance hole is formed by segment assembly, omitting the cast-in-place concrete operation of the secondary lining. When starting, the reaction frame is installed at the end wall of the starting shaft, and the 0-ring segment is assembled, thus omitting the installation of the negative ring segment and avoiding the removal of the negative ring segment.

4. For the shield construction of the first tunnel in step 3 of the ultra-short starting shaft TBM integral starting method according to claim 1, it specifically includes: After the construction of the tunneling advance hole is completed, shield tunneling method is used for the first tunnel side. The main machine, the connection bridge, and the 1st - 4th trolleys are first lowered into the shaft for assembly, and the 5th and 6th trolleys are temporarily placed on the ground. Before the 5th and 6th trolleys are lowered into the shaft for assembly, a sewage sump is added in the starting shaft, and a sewage pump is installed for sewage treatment. The cables are suspended on the tunnel wall with a surplus length. When the conditions for the whole machine to be in place are met, the 5th and 6th trolleys are respectively hoisted into the shaft for assembly. The shield enters the normal tunneling state, and the muck removal and feeding are both carried out by the hoisting equipment in the starting shaft.

5. For the track construction in the first tunnel in step 4 of the ultra-short starting shaft TBM integral starting method according to claim 1, it specifically includes: After the first tunnel is driven through, the second tunnel boring equipment is lowered into the shaft for assembly, commissioning, and tunneling. Due to the limitation of the space in the launching shaft, after the equipment is lowered into the shaft, except for the pea gravel that can be transported to the bottom of the launching shaft through pipes, other hoisting operations cannot be carried out in the launching shaft. For the initial mucking and feeding of the second tunnel, the hoisting shaft after the first tunnel is driven through needs to be used for auxiliary operations. Since the length of the hoisting shaft is short and the space is limited, a double-track transportation line needs to be laid near the hoisting shaft in the first tunnel, and 4 sets of single turnout switches are installed to form two sets of double-track transfer lines. The length of each line is not less than the length of a whole train formation, and the shortest distance between the two lines is not less than the length of 1 slag bucket car plus the length of a battery car, which is used for the horizontal transportation of the mucking trucks and segment flatbed trucks of the second tunnel by means of towing or pushing by the battery car for reformation.

6. The TBM construction of the second tunnel described in step 5 of the ultra-short launching shaft TBM integral launching method according to claim 1 specifically includes: After the shield tunnel of the first tunnel is driven through, the second tunnel TBM equipment is lowered into the shaft for assembly. The assembly procedure for lowering into the shaft is the same as the conventional method. After being lowered into the shaft, the trailing gantries are all placed in the first tunnel. The shield body is pushed forward into the jacking tunnel, and the reaction frame backrest is hoisted integrally by the mucking gantry crane. The backrest is installed at the side wall of the TBM tunnel in the launching shaft and is closely attached to the side wall. Adjust the horizontal and verticality of the reaction frame backrest. Weld the left and right columns firmly to the embedded parts on the bottom plate of the launching shaft, add diagonal braces on both sides at the top of the columns, and fix the diagonal braces to the side walls on both sides. Add 3 steel pipe diagonal braces on the left and right in the middle of the columns, and weld the steel pipe diagonal braces firmly to the backrest and the embedded parts on the bottom plate. Measure and review the TBM attitude. The shield body is perpendicular to the plane of the reaction frame backrest. Connect the TBM equipment pipelines, commission the TBM equipment, assemble the 0-ring segments with the segment erector at the shield tail. The 0-ring segments are closely attached to the plane of the reaction frame backrest and are fixed to the reaction frame with segment bolts. The gaps between the segments and the tunnel wall at the reaction frame are blocked with red bricks, and the remaining gaps are sealed with grease. The mucking and feeding of the TBM adopt the conventional train formation method, and the horizontal transportation passes through the first tunnel, and is hoisted out and lowered into the shaft at the hoisting shaft of the first tunnel. The TBM drives and constructs the 0-ring segment assembly. Weld "L"-shaped angle steels on the shield tail to stabilize the segments. After the segments are withdrawn from the shield tail, open the hoisting holes, and immediately support the segments with positive and negative thread steel sleeves. After the segments are withdrawn from the shield tail, start to blow-fill pea gravel. Before blowing-fill pea gravel, first remove the support sleeves. Set a water stop ring hoop every 10 - 15 rings. The water stop ring hoop adopts the injection of cement-sodium silicate double liquid slurry, and the rest is backfilled with cement slurry.

7. The mucking out of the hoisting shaft and the lowering of segments described in step 6 of the ultra-short launching shaft TBM integral launching method according to claim 1 specifically includes: A crawler crane, a forklift and a muck truck are arranged at the first tunnel hoisting shaft for temporary muck discharging and segment lowering during the transition. The crawler crane is used for the vertical transportation of muck discharging and feeding in the second tunnel, and is used for loading and unloading the gravel tank, muck bucket, segments and turnover materials. During the horizontal transportation scheduling, the whole train formation is placed in one of the two double tracks, parked on the main line between two turnouts. The battery car transports each vehicle back and forth through the two turnouts to the first tunnel hoisting shaft for material loading and unloading. The full muck bucket is hoisted and loaded onto the truck and transported to the TBM launching yard for unloading. At the launching shaft, the muck is then hoisted by a gantry crane and unloaded into the muck pit, and the empty bucket is transported back to the temporary launching yard at the first tunnel hoisting shaft for lowering into the well; the empty gravel tank is re-formed, horizontally transported to the launching shaft, and the gravel is loaded into the tank using a vertical pipeline at the launching shaft; the segments are stored in the hoisting shaft yard, transported to the crane position by a forklift, and hoisted by the crane and loaded onto the truck at the hoisting shaft.

8. According to the method for the overall launching of the ultra-short launching shaft TBM described in claim 1, the train transportation formation in step 7 specifically includes the following steps: Step 7.1 Segment car formation: Under normal operation of the ore car train, its formation is a battery car + 4 muck cars + 1 gravel car + 2 segment cars. The battery car pulls the whole train formation of ore cars, horizontally transports and parks the train full of muck on the main line between the two turnouts of the second double track. The wheels of the train to be transported are locked with iron shoes, the interlock between the battery car and the muck car is removed. The battery car passes through the two turnouts of the second double track, transports to the second segment car, connects to the second segment car, removes the interlock between the second segment car and the first segment car. The battery car pulls the second segment car through the second double track turnouts and the second double track, pushes the second segment car to the position of the first tunnel hoisting shaft, and the segment is hoisted and placed on the second segment car by the crawler crane. The battery car pulls the second segment car with a heavy load through the second double track, enters and parks on the main line between the two turnouts of the first double track, and is locked with iron shoes, waiting for re-formation; the connection between the battery car and the second segment car is removed, the battery car horizontally transports through the first double track turnouts and the first double track, enters the main line train parking position of the second double track, connects to the first segment car, removes the interlock between the first segment car and the gravel car. The battery car pulls the first segment car through the second double track turnouts and the second double track, pushes the first segment car to the hoisting shaft, and the segment is hoisted and placed on the first segment car by the crawler crane. The battery car pulls the first segment car with a heavy load through the second double track, parks between the first double track turnout and the second double track turnout and locks it. The interlock between the battery car and the first segment car is removed. The battery car enters the main line of the first double track, reaches the position of the second segment car, and connects to it. The battery car pushes the second segment car to the position of the first segment car and connects to the first segment car. The battery car pulls the second segment car and the first segment car into and parks on the main line of the first double track, and is locked with iron shoes, waiting for re-formation again; Step 7.2 Gravel car formation: After the re - formation of the segment cars is completed, the pea gravel cars are reformed. The pea gravel cars are reformed with empty cars. When the whole train is reformed and transported to the launching shaft, pea gravel pipelines are used for loading. After the heavy - load re - formation of 2 segment cars is completed, the battery locomotive returns to the position of the pea gravel cars, connects with the pea gravel cars, removes the interlock between the pea gravel cars and the muck cars. The battery locomotive pulls the pea gravel cars and parks them between the first set of double - track turnouts and the second set of double - track turnouts, and locks them with rail boots. Then, the interlock between the battery locomotive and the pea gravel cars is removed. The battery locomotive enters the main line of the first set of double - track through the first set of double - track turnouts and the first double - track, connects with the segment cars, pushes the segment cars to the position of the pea gravel cars, and connects with the pea gravel cars. Then, it pulls 2 segment cars + 1 pea gravel car and parks them at the main line position of the first set of double - track, and locks them with rail boots. Wait for the muck cars to unload, and then reform the empty cars; Step 7.3 Muck car formation: Then, the battery locomotive returns to the position of the fourth muck car again, connects with the muck car, removes the interlock between the fourth muck car and the third muck car. The battery locomotive drags the fourth fully - loaded muck car, and pushes the fourth muck car through the second set of double - track turnouts and the second double - track to the hoisting shaft. Use a crawler crane to lift the slag bucket onto the transport vehicle, fix it firmly, transport it by truck to the launching shaft, use a gantry crane to lift and unload the slag bucket into the muck pit. After unloading the muck, transport the empty slag bucket back to the hoisting shaft, use a crawler crane to lift the slag bucket onto the fourth muck car. The battery locomotive drags the fourth empty muck car and parks it between the first set of double - track turnouts and the second set of double - track turnouts, removes the interlock between the battery locomotive and the empty muck car, and locks the empty muck car with rail boots. The battery locomotive enters the main line of the first double - track through the first set of double - track turnouts and the first double - track, reaches the position of the segment cars, connects with the new formation, pushes the pea gravel cars and the new formation of 2 segment cars to the parking position of the empty fourth muck car, and connects with it. The battery locomotive drags the new formation and returns to the main line of the first set of double - track again, and locks it with rail boots. And so on, push the other 3 muck cars to the hoisting shaft for unloading one by one, and reform them to form a whole - train formation. The battery locomotive returns to the initial state, pushes the whole - train formation of battery locomotive + 4 muck cars + 1 pea gravel car + 2 segment cars to the launching shaft, parks the pea gravel car under the vertical transport pipeline of pea gravel in the launching shaft, and drops the pea gravel into the pea gravel hopper. After filling with pea gravel, the battery locomotive continues to push the whole - train formation to the TBM tunneling area for use.

9. According to the ultra - short launching shaft TBM integral launching method described in claim 1, the muck discharging and segment lowering at the launching shaft in step 8: For the grouting material used in the initial stage, cement slurry is mixed in the batching plant installed at the launch shaft site, and then directly pumped into the segment lifting hole by a piston pump to grout and consolidate the pea gravel behind the segments. After the TBM of the second tunnel meets the requirement of the whole machine entering the second tunnel, the mucking and feeding of the second tunnel are all carried out at the launch shaft, and the normal tunneling state is restored. At this time, the double-track at the hoist shaft in the first tunnel can be removed, and the TBM continues to tunnel. As the tunneling distance of the second tunnel increases, in order to improve the TBM tunneling efficiency, double-track can be set within the range of 140 - 160 m at the launch shaft, and the launch shaft is used for mucking and feeding. The train formation consists of 1 battery car, 4 muck cars, 1 pea gravel car, and 2 segment cars, and 2 trains are used for transportation. The mucking and segment lowering both adopt gantry cranes for vertical transportation, and the pea gravel is horizontally transported by hoppers and belt conveyors and vertically transported through pipes into the pea gravel hopper. The grouting material uses bagged cement. A cement slurry mixing tank is added to the trailing gantry, and the cement slurry is mixed on-site and injected behind the segments by a piston pump to consolidate the pea gravel. The pea gravel and grouting backfill follow in a timely manner. When the segment exits the shield tail, pea gravel is promptly blown and filled, and the grouting time shall not lag behind 10 - 15 rings to ensure the stable attitude of the segments.

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