Shield construction cavern for shield non-negative-ring starting

Abstract

The utility model provides a shield construction cavern without negative ring starting of a shield. The shield construction cavern comprises a miniature expansion section, a concrete guide table and a counter-force frame. The micro expanded section is positioned on one side, close to a tunnel face, in the construction cavern; the section of the micro expanded section is larger than the standard section of the starting hole; the concrete guide table is arranged in the shield launching hole and is arc-shaped; the counter-force frame is of a quasi-circular ring frame type structure, is installed in the micro expansion section and is supported on the reinforced concrete frame on the bottom layer. The method comprises the following steps: arranging a micro expansion section in a shield launching hole, performing reinforced support on the expansion section, constructing a concrete guide table in the shield launching hole, arranging a counter-force frame on the expansion section, assembling a positive ring duct piece, backfilling pea gravel behind the wall of the positive ring duct piece in the launching process, performing grouting reinforcement and the like. The problem that the negative ring duct piece needs to be arranged in the shield launching process is solved, the construction safety is guaranteed, the construction quality is guaranteed, the construction period is shortened, and the construction cost is saved.

Description

Technical Field

[0001] This application relates to shield tunneling construction projects in municipal engineering, highway engineering, water conservancy, mining, etc., and in particular to a shield tunneling tunnel with a shield tunneling starting without a negative ring. Background Technology

[0002] As an advanced underground or underwater tunnel construction technology, the shield tunneling method relies heavily on the shield machine, the core equipment of which directly affects the quality and efficiency of the tunnel project. The initial launch of the shield machine, as the starting stage of the entire construction process, directly impacts the safety and smoothness of subsequent tunneling operations.

[0003] Conventional tunnel boring machine (TBM) launches require the use of negative ring segments, also known as temporary segments. These are ring-shaped segments installed between the reaction frame and the TBM jacks during launch. The primary function of the negative ring segments is to provide the necessary forward propulsion force for the TBM. At the very beginning of the TBM's excavation, its propulsion cylinders are unsupported and cannot directly contact any object to generate reaction force. At this point, the negative ring segments, through the reaction frame, transmit and amplify the force required for the TBM's forward movement, ensuring a smooth start and entry into normal tunneling operations.

[0004] However, the negative ring segment is located between the tunnel boring machine and the reaction frame in a confined space, making dismantling difficult and posing safety hazards. Furthermore, dismantling is not only time-consuming and labor-intensive but also increases construction costs and reduces overall construction efficiency. Therefore, how to achieve initial construction without a negative ring segment has become a critical issue that urgently needs to be addressed in the field of tunnel boring machine technology. Utility Model Content

[0005] This application addresses the problem of needing to remove negative ring segments after existing shield tunneling construction by providing a shield tunneling tunnel without a negative ring for starting the tunnel. The tunnel includes: a micro-enlargement section, a concrete guide platform, and a reaction frame. The micro-enlargement section is located in the tunnel near the working face, 8 meters away from the working face, and extends towards the shaft. The cross-section of the micro-enlargement section is larger than that of a standard starting tunnel. The concrete guide platform is located inside the shield starting tunnel and is arc-shaped, constructed of C30 reinforced concrete. The reaction frame is a near-circular ring-frame structure, installed within the micro-enlargement section and supported on a bottom reinforced concrete frame.

[0006] In one feasible implementation, the cross-section of the micro-enlarged section differs from that of the standard starting tunnel by 2.2m.

[0007] In one feasible implementation, a backfill reinforcement area is also included; the backfill reinforcement area is located within the standard starting tunnel initial support structure between the working face and the reaction frame, and is formed by blowing gravel and grouting reinforcement, wherein the grouting material used for grouting reinforcement is a cement-based composite material.

[0008] In one feasible implementation, a positive ring segment structure is also included; the positive ring segment structure includes multiple positive ring segments, which are fixed by bolts, and a waterproof sealing strip is provided between adjacent positive ring segments; the backfill reinforcement area is also provided behind the wall of the positive ring segment structure.

[0009] In one feasible implementation, the micro-enlarged section is further provided with a reinforced support structure, which includes: a Φ25 hollow grouting anchor tie structure, a waterproof layer, 450mm thick C45 reinforced concrete, and pre-embedded welded parts.

[0010] In one feasible implementation, double rows of P43 steel rails are pre-embedded in the concrete guide platform.

[0011] In one feasible implementation, the reaction frame is provided with two rows of three steel pipe supports at the rear.

[0012] In one feasible implementation, the reaction frame is welded to the embedded parts at the corresponding positions of the secondary lining.

[0013] This application provides a shield tunneling tunnel without a negative ring for shield tunneling launch, comprising: a micro-enlargement section, a concrete guide platform, and a reaction frame. By setting up a micro-enlargement section within the shield launch tunnel, reinforcing the enlargement section, constructing a concrete guide platform in the launch tunnel, installing a reaction frame in the enlargement section, assembling positive ring segments, backfilling with gravel behind the positive segment walls during launch, and grouting reinforcement, this solution solves the problem of needing to set up a negative ring segment during shield tunneling launch, ensuring construction safety, guaranteeing construction quality, saving construction time, and reducing construction costs. Attached Figure Description

[0014] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the embodiments of the present invention. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0015] Figure 1 This is an exemplary plan view of the shield tunneling starting shaft shown in an embodiment of this application;

[0016] Figure 2This is an exemplary cross-sectional view of the standard starting tunnel shown in an embodiment of this application;

[0017] Figure 3 This is a cross-sectional view of the micro-enlargement section of the shield tunneling starting tunnel, as exemplarily shown in an embodiment of this application.

[0018] Explanation of reference numerals: 10 - Miniature enlarged section; 20 - Standard starting tunnel; 30 - Working face; 11 - Reinforced support structure; 21 - Concrete guide platform. Detailed Implementation

[0019] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a full understanding of the implementation of embodiments of the present invention.

[0020] Existing tunnel boring machine (TBM) launch systems require negative ring segments, whose primary function is to provide the necessary forward propulsion force for the TBM. At the start of TBM excavation, its propulsion cylinders are unsupported and cannot directly contact any object to generate reaction force. Therefore, the negative ring segments, through a reaction frame, transmit and amplify the force required for the TBM's forward movement, ensuring a smooth start and entry into normal excavation. However, the negative ring segments are located between the TBM and the reaction frame in a confined space, making dismantling difficult and posing safety hazards. Furthermore, dismantling is not only time-consuming and labor-intensive but also increases construction costs and reduces overall construction efficiency.

[0021] This application addresses the aforementioned problems by providing a shield tunneling tunnel without a negative ring for starting the tunnel boring machine (TBM). The TBM includes three structures: a micro-enlargement section 10, a concrete guide platform 21, and a reaction frame. This enables the safe and efficient starting of the TBM while avoiding the use of traditional negative ring segments and the associated dismantling difficulties.

[0022] Among them, reference Figure 1 As shown, Figure 1 This is a plan view of the shield tunneling starting shaft. The micro-enlargement section 10 is located in the construction chamber near the working face, 8m away from the working face, and extends towards the shaft side. The cross-section of the micro-enlargement section 10 is larger than that of the standard starting shaft 20. A concrete guide platform 21 is set inside the shield tunneling starting shaft. The concrete guide platform 21 is arc-shaped and constructed of C30 reinforced concrete. The reaction frame is a near-circular ring frame structure, installed inside the micro-enlargement section 10, and supported on the bottom reinforced concrete frame.

[0023] Specifically, the micro-enlargement section 10 is located on the side of the construction tunnel near the tunnel face (i.e., the tunnel excavation face), approximately 8 meters away from the face. This distance ensures sufficient space for debugging and preparation when the tunnel boring machine (TBM) is launched. Furthermore, the micro-enlargement section 10 extends towards the shaft to better utilize the shaft as a channel for construction support and material transport. The cross-section of the micro-enlargement section 10 is designed to be larger than that of the standard launching tunnel 20. This design not only provides a spacious operating environment for the TBM's launch but also reserves ample space for potential subsequent equipment adjustments or emergency handling.

[0024] Furthermore, an arc-shaped concrete guide platform 21 is installed inside the shield tunneling launch shaft. Constructed of C30 reinforced concrete, the guide platform possesses high strength and stability to ensure it can withstand the enormous thrust of the tunnel boring machine (TBM) during launch. The design of the concrete guide platform 21 provides a smooth and continuous tunneling guidance for the TBM, and its arc shape effectively disperses the impact forces during tunneling, protecting the integrity of the tunnel structure. In addition, the concrete guide platform 21 simplifies the construction process and reduces the workload required for frequent adjustments to the tunneling direction as in traditional methods.

[0025] The reaction frame adopts a near-circular ring-frame structure and is installed within the micro-enlargement section 10. Its stability and reliability are ensured by supporting it on the underlying reinforced concrete frame. Furthermore, the ring-shaped structure of the reaction frame effectively distributes the reaction force from the tunnel boring machine (TBM) throughout the entire tunnel structure, preventing structural damage caused by localized stress concentration. The presence of the reaction frame provides continuous and stable propulsive force support for the TBM, ensuring that it can begin tunneling operations smoothly and efficiently.

[0026] As described above, the shield tunneling chamber without a negative ring in this embodiment cleverly combines the micro-enlargement section 10, the concrete guide platform 21, and the reaction frame. This not only achieves a safe and efficient start for the shield machine but also avoids the use of traditional negative ring segments and the resulting dismantling difficulties. Furthermore, this solution provides stable and reliable support and guidance for the subsequent tunneling operations, ensuring the smooth progress of the entire tunnel project.

[0027] In some embodiments of this application, the cross-section of the micro-enlarged section 10 differs from that of the standard starting tunnel 20 by 2.2m.

[0028] Specifically, refer to Figure 2 and Figure 3 As shown, Figure 2 This is a standard starting tunnel cross-section diagram. Figure 3This is a cross-sectional view of the micro-enlargement section of the tunnel boring machine (TBM) launching tunnel. During the launching phase, the TBM requires sufficient space for commissioning and preparation, including adjusting the tunneling direction and checking equipment status. The 2.2-meter cross-sectional difference provides a more spacious operating environment for the TBM, ensuring a smooth launching process. Simultaneously, various unforeseen circumstances may arise during tunneling, such as geological anomalies and equipment malfunctions. The design of the micro-enlargement section 10 provides ample space for these emergency responses, ensuring the construction team can quickly and effectively address various challenges.

[0029] Enlarging the tunnel cross-section reduces the number of turns and the turning angle of the tunnel boring machine during excavation, thus simplifying the construction process and improving efficiency. The wider cross-section also facilitates the transportation and storage of construction materials. Furthermore, the 2.2m expansion of the micro-enlargement section 10 provides a spacious working environment, offering the construction team better operating space and visibility, helping to reduce safety hazards during construction and improve efficiency.

[0030] In some embodiments of this application, the shield tunneling tunnel without a negative ring starting also includes a backfill reinforcement area; the backfill reinforcement area is located in the initial support structure of the standard starting tunnel 20 between the tunnel face and the reaction frame, and is formed by blowing gravel and grouting reinforcement, wherein the grouting material used for grouting reinforcement is a cement-based composite material.

[0031] Pebble, as a hard, uniformly sized granular material, possesses excellent permeability and load-bearing capacity, effectively filling voids within the initial support structure and improving the overall density and stability of the structure. During grouting reinforcement, the cement-based composite material used, a high-performance grouting material, exhibits high strength, high durability, and good bonding properties, enabling it to tightly bond with the pea gravel to form a dense and robust reinforcement layer.

[0032] By filling the voids within the initial support structure, the overall density and stability of the structure are improved, effectively preventing tunnel deformation and collapse. The combination of gravel and cement-based composite materials gives the backfilled reinforced area a high load-bearing capacity, capable of withstanding the enormous reaction forces during tunnel boring machine excavation, ensuring the smooth progress of construction. The formation of the backfilled reinforced area reduces voids and water accumulation within the tunnel, improving the construction environment and providing the construction team with better operating space and visibility.

[0033] In some embodiments of this application, the shield tunneling chamber without a negative ring starting also includes a positive ring segment structure; the positive ring segment structure includes multiple positive ring segments, which are fixed by bolts, and waterproof sealing strips are provided between adjacent positive ring segments; the backfill reinforcement area is also set behind the wall of the positive ring segment structure.

[0034] Specifically, tunnel lining segments are typically made of high-strength, corrosion-resistant materials, such as reinforced concrete or special alloys. Their shape and dimensions are precisely calculated to ensure a smooth, continuous tunnel wall after assembly. The tunnel lining segments are the primary load-bearing structure during tunnel excavation, resisting pressure from the ground and the excavation process, and providing essential support and stability for the tunnel. Furthermore, the assembly precision and waterproofing performance of the tunnel lining segments have a significant impact on the long-term operation and safety of the tunnel.

[0035] Bolts, as key components connecting the tunnel segments, are typically made of high-strength, corrosion-resistant alloy materials. Bolt fixing not only ensures a tight connection and overall stability between the tunnel segments, but also allows for adjustments to bolt preload to accommodate deformation and settlement during tunnel excavation. Furthermore, the disassembly and reuse of bolts reduce construction costs and environmental impact.

[0036] Waterproof sealing strips are typically made of elastic, wear-resistant, and corrosion-resistant materials, such as rubber or silicone. Their shape and size are precisely designed to ensure a tight fit within the gaps between the tunnel segments. Waterproof sealing strips prevent groundwater and other liquids from seeping into the tunnel interior, and also reduce humidity and the accumulation of corrosive substances inside the tunnel, thereby extending the tunnel's service life and safety.

[0037] Secondly, if the voids behind the tunnel segments are not backfilled and reinforced in a timely manner during the initial stage, it may lead to deformation and instability of the tunnel structure. Therefore, using gravel for backfilling and reinforcing it with grouting to form a dense filling layer is an important measure to ensure the stability and safety of the tunnel structure. Gravel has good permeability and load-bearing capacity, which can quickly fill voids and disperse pressure; while grouting reinforcement can further improve the strength and stability of the filling layer, ensuring the safety and reliability of the tunnel structure in long-term operation.

[0038] In some embodiments of this application, the micro-enlarged section 10 is further provided with a reinforcing support structure 11, which includes: a Φ25 hollow grouting anchor tie structure, a waterproof layer, 450mm thick C45 reinforced concrete, and pre-embedded welded parts.

[0039] The main function of the Φ25 hollow grouting anchor bolt tie structure is to provide strong tensile and shear strength, effectively preventing loosening or collapse of the surrounding rock that may occur during the excavation of the micro-enlargement section 10. The grouting process of the anchor bolt also improves the physical and mechanical properties of the surrounding rock, enhancing its bearing capacity and stability. The main function of the waterproof layer is to prevent groundwater or other liquids from seeping into the tunnel through the tunnel walls, reduce the humidity inside the tunnel, prevent damage to the tunnel structure due to moisture erosion, and simultaneously ensure the normal operation of equipment and the safety of construction personnel within the tunnel.

[0040] The C45 reinforced concrete layer is the main load-bearing layer of the micro-enlargement section 10, capable of withstanding the enormous pressure from the strata and during the tunneling process, ensuring the overall stability and safety of the tunnel structure. At the same time, its thickness and strength design also take into account various possible loads during subsequent construction, such as the thrust of the tunnel boring machine and the assembly pressure of the tunnel segments.

[0041] The embedded welded components are mainly used to connect with other structural components in subsequent construction, such as the guide frame of the tunnel boring machine and the connecting components of the tunnel segments. Through welding or bolting, the embedded welded components can tightly connect the micro-enlarged section 10 with the subsequent construction structure to form a complete and stable tunnel structure system.

[0042] In some embodiments of this application, double rows of P43 steel rails are pre-embedded within the concrete guide platform. P43 steel rails, as a high-quality steel, possess high strength and rigidity. Pre-embedding them within the concrete guide platform creates a composite structure with the concrete, significantly improving the load-bearing capacity and deformation resistance of the concrete guide platform. During the tunnel boring machine's (TBM) launch, the concrete guide platform needs to withstand the weight of the TBM and the reaction forces during excavation. The pre-embedding of double rows of P43 steel rails provides more stable and reliable support for the concrete guide platform, ensuring a smooth and safe launch of the TBM.

[0043] P43 rails, with their precise dimensions and shape, are pre-embedded within the concrete guide platform to form a continuous and accurate guide track. This helps the tunnel boring machine (TBM) to excavate in the correct direction from the initial stage, reducing deviations and errors. Simultaneously, double rows of P43 rails can also serve as positioning benchmarks in subsequent construction. For example, during segment assembly, the position and angle of the segments can be determined based on the rail positions, ensuring the accuracy and continuity of segment assembly.

[0044] In some embodiments of this application, the reaction frame is provided with two rows of three steel pipe supports at each end. The steel pipe supports, as the rear support structure of the reaction frame, primarily provide additional support force, enhancing the overall stability of the reaction frame. During the tunnel boring machine's excavation process, the reaction frame needs to withstand the enormous thrust from the machine, and the steel pipe supports effectively disperse and transfer this thrust, preventing deformation or damage to the reaction frame.

[0045] Steel pipe supports possess high rigidity, effectively resisting deformation caused by external loads. By installing two rows of three steel pipe supports each, the rigidity of the reaction frame can be significantly increased, enabling it to better withstand various loads during tunneling. The steel pipe supports ensure the stability of the reaction frame during tunneling, thereby ensuring the tunnel boring machine (TBM) can excavate in the predetermined direction, reducing deviations and errors. If the reaction frame becomes unstable or is damaged during TBM tunneling, it could lead to serious consequences such as tunnel collapse. The steel pipe supports effectively prevent this from happening, ensuring the safety of construction personnel and the stability of the tunnel.

[0046] In some embodiments of this application, the reaction frame and the embedded parts at corresponding positions of the secondary lining are welded together. Welding, as a high-strength connection method, can firmly connect the reaction frame and the embedded parts of the secondary lining together to form an integral structure. This connection method can significantly improve the strength of the connection parts, enabling them to withstand greater loads and deformations.

[0047] During tunnel boring machine (TBM) excavation, the reaction frame needs to withstand the enormous thrust from the TBM and transfer it to the surrounding soil. Welded connections effectively prevent relative displacement or deformation between the reaction frame and the secondary lining, thus ensuring the stability and safety of the entire structure. Furthermore, welded connections offer high strength and stability, providing reliable connection points for subsequent construction. For example, during segment assembly, welded connections can be used for positioning and fixing, ensuring the accuracy and continuity of segment assembly.

[0048] This application provides a specific project implementation case to illustrate the construction method of the shield tunneling chamber with shield tunneling starting without a negative ring.

[0049] Specifically, the project includes a shield / TBM launching shaft and track-exit shaft in the Xiafu section. The shield section uses two composite shield machines, which are launched separately from the small mileage end of the launching shaft. Each line is excavated for about 360m to the lifting shaft. The shield excavation diameter is 6.49m, with precast segment lining, segment thickness of 350mm, and ring width of 1.5m.

[0050] The shield tunneling starting tunnel is 45m long. From the standard starting tunnel 20 towards the tunnel face 30, a 30m standard starting tunnel 20, a 7m micro-enlargement section 10, and an 8m standard starting tunnel 20 are set up sequentially. The cross-section of the standard starting tunnel 20 is between a circle and a horseshoe shape, with a height of 7.5m and a width of 7.3m. The 30m standard section is in the initial support completed state at the start of the tunneling, while the 8m standard section on the side of the tunnel face 30 is in the initial support and concrete guide platform 21 completed state.

[0051] The miniature enlarged section 10 is horseshoe-shaped, 9.89m high and 9.5m wide. At the start of excavation, both the secondary lining and the concrete guide platform 21 were completed. This miniature enlarged section 10 is approximately 2.2m wider than the standard starting tunnel 20. Due to the enlargement causing a small clearance between the two tunnels, Φ25 hollow grouting anchor bolts were installed between them for tie rods, along with a waterproof layer and 450mm thick C45 reinforced concrete to ensure tunnel stability. During the pouring of the secondary lining, welded components connecting to the reaction frame were pre-embedded, avoiding the location of the concrete guide platform.

[0052] After the secondary lining construction of the micro-enlargement section 10 is completed, the construction of the guide platform for this section and the 8m standard section on the 30th side of the tunnel face will commence. The concrete guide platform 21 is set in an arc shape, using C30 reinforced concrete, with double rows of P43 steel rails pre-embedded within it. The concrete guide platform 21 is an inclined platform with the same slope as the tunnel track, and the distance between the highest point of the concrete guide platform 21 and the rail surface remains constant at 840mm. The rail brackets are made of C25 threaded steel, with a pair erected every 1m along the tunnel centerline. Before pouring concrete, the surveying team must re-measure the plane and elevation positions of the pre-positioned embedded parts, and pour concrete only after the requirements are met. The bolts of the embedded parts are welded to the steel plates using plug-hole welding, with a weld height of not less than 8mm; the bolts should be welded perpendicular to the steel plate surface, and the bolts are made of 22mm diameter threaded steel. Before installing the secondary lining reinforcement cage, two rows of threaded steel must be welded to the embedded parts of the invert arch.

[0053] The reaction structure is specially designed, with a near-circular ring frame reaction frame. The center of the ring frame must be able to allow passage for the tunnel boring machine and material transport vehicles. Columns are set on both sides, crossbeams are set on the top, and the ring frame is set inside. Each of the two columns is supported by three steel pipes. Each stress-bearing part of the reaction frame is welded to the pre-embedded parts at the corresponding positions of the secondary lining to ensure structural stability during the initial launch.

[0054] As described above, this application provides a shield tunneling tunnel without a negative ring for shield tunneling launch, comprising: a micro-enlargement section, a concrete guide platform, and a reaction frame. This application solves the problem of needing to install a negative ring segment during shield tunneling launch by setting up a micro-enlargement section within the shield launch tunnel, strengthening the support of the enlargement section, constructing a concrete guide platform in the shield launch tunnel, setting up a reaction frame in the enlargement section, assembling positive ring segments, backfilling gravel behind the positive segment walls during launch, and grouting reinforcement. This ensures construction safety, guarantees construction quality, saves construction time, and reduces construction costs.

[0055] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the disclosure in the specification and the embodiments. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein.

Claims

1. A shield tunneling chamber for shield tunneling without a negative ring starting, characterized in that, include: Miniature enlarged section (10), concrete guide platform (21), and reaction frame; The micro-enlarged section (10) is located on the side of the working face (30) in the construction cavern, at a distance of 8m from the working face (30), and extends toward the shaft side. The cross-section of the micro-enlarged section (10) is larger than that of the standard starting tunnel (20). The concrete guide platform (21) is set inside the shield tunneling starting hole. The concrete guide platform (21) is arc-shaped and constructed of C30 reinforced concrete. The reaction frame is a near-circular ring frame structure. The reaction frame is installed inside the micro-enlarged section (10) and supported on the bottom reinforced concrete frame.

2. The shield tunneling chamber with a negative ring-less starting method according to claim 1, characterized in that, The cross-section of the micro-enlarged section (10) differs from that of the standard starting tunnel (20) by 2.2m.

3. The shield tunneling chamber for shield tunneling without a negative ring starting as described in claim 1, characterized in that, It also includes backfilled and reinforced areas; The backfill reinforcement area is located within the initial support structure of the standard starting tunnel (20) between the working face (30) and the reaction frame. It is filled with pea gravel and reinforced by grouting to form the backfill reinforcement area. The grouting material used for grouting reinforcement is a cement-based composite material.

4. A shield tunneling chamber with a negative ring-less starting method according to claim 3, characterized in that, It also includes positive ring segment structures; The positive ring segment structure includes multiple positive ring segments, which are fixed by bolts, and a waterproof sealing strip is provided between adjacent positive ring segments; The backfill reinforcement area is also located behind the wall of the positive ring segment structure.

5. A shield tunneling chamber for shield tunneling without a negative ring starting as described in claim 1, characterized in that, The micro-enlarged section (10) is also provided with a reinforced support structure (11), which includes: a Φ25 hollow grouting anchor tie structure, a waterproof layer, 450mm thick C45 reinforced concrete and pre-embedded welded parts.

6. A shield tunneling chamber for shield tunneling without a negative ring starting, as described in claim 1, is characterized in that, The concrete guide platform (21) is pre-embedded with double rows of P43 steel rails.

7. A shield tunneling chamber for shield tunneling without a negative ring starting, as described in claim 1, is characterized in that, The reaction frame is supported by two rows of three steel pipes at the rear.

8. A shield tunneling chamber for shield tunneling without a negative ring starting as described in claim 1, characterized in that, The reaction frame is welded to the embedded parts at the corresponding positions of the secondary lining.

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