Complex soft rock double-layer primary support super-large section tunnel and construction method

Abstract

The invention relates to a complex soft rock double-layer primary supporting super-large section tunnel and a construction method. The complex soft rock double-layer primary supporting super-large section tunnel comprises a long pipe shed cover arch supporting system, a deformation control strong supporting structure, an anti-disengaging early-warning lining pouring trolley, a temporary inverted arch deformation control structure and a buffering yielding supporting system. The method has the beneficial effects that the curved surface formwork can be rapidly installed on the upper portion of the guide pipe and the lower portion of the steel arch frame, the installation efficiency is high, stability is good, and the construction period is shortened; a long pipe shed and a small guide pipe penetrate through the deformation control strong supporting structure and are driven into a tunnel, grouting is conducted, the overall stability of the supporting structure is enhanced, and the complex soft rock geology is reinforced; concrete pouring is monitored in real time, and the compactness of vault concrete is guaranteed; section steel is clamped in the inverted arch, reinforcing connecting ribs are welded between the section steel in a penetrating mode, surrounding rock collapse is prevented, and tunnel construction safety is guaranteed. And a buffer yielding support device is arranged between the interface and the double-layer arch frame, so that the pressure at the interface of the layered rock and soil stratum is in smooth transition, and the overall balance is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of tunnel engineering, and particularly relates to a complex soft rock double-layer primary support super-large section tunnel and a construction method. BACKGROUND

[0002] As an important part of modern transportation infrastructure, the construction scale and quantity of large section tunnels are increasing. So far, the tunnel construction concept of "complex geology, large diameter, high water pressure and long distance" has been formed, but there are still many difficulties in dealing with problems such as rock leakage and broken rock, especially for soft surrounding rock large section tunnels. The construction method of large section tunnel is different from that of small section tunnel, especially under complex conditions, which not only affects the safety of tunnel construction, but also involves how to ensure the construction speed. The research on the construction technology of soft and broken surrounding rock super-large section tunnel is still insufficient, and considering the uncertainty of geological conditions and effectively predicting and preventing deformation in the tunnel construction process are still the key problems to be solved in the construction process.

[0003] Therefore, in view of the deficiencies in the construction of previous complex soft rock large section tunnels, there is an urgent need for a new construction method for complex soft rock super-large section tunnels to improve construction efficiency, improve construction quality and ensure safe and reliable construction process. SUMMARY

[0004] The purpose of the present application is to overcome the deficiencies in the prior art and provide a complex soft rock double-layer primary support super-large section tunnel and a construction method.

[0005] The complex soft rock double-layer primary support super-large section tunnel comprises a long pipe shed arch support system, a deformation control strong support structure, a void-preventing early warning lining pouring trolley, a temporary inverted arch deformation control structure and a buffer yielding support system. The long pipe shed arch support system is fixed in the tunnel portal soil and fixed on the ground at both ends. The inner and outer arc surfaces of the long pipe shed arch support system are provided with a formwork for pouring the arch. The deformation control strong support structure is arranged on the arch. The deformation control strong support structure is provided with a long pipe shed and a small guide pipe which are inserted into the tunnel. The void-preventing early warning lining pouring trolley is located in the tunnel, and the tunnel arc surface is poured with a lining. The tunnel bottom is provided with an inverted arch backfilled with concrete. The different soil contact surfaces outside the tunnel are boundary surfaces, the tunnel is provided with a double-layer arch frame, and the buffer yielding support device is arranged between the boundary surface and the double-layer arch frame.

[0006] Preferably, the long-tube shed arch support system includes an arch frame foundation, a steel arch frame, upper fixed steel sections, and lower fixed steel sections. The arch frame foundation is fixed to the ground, and both ends of the steel arch frame are fixed to the arch frame foundation. Multiple guide pipes are provided on the steel arch frame, with an upper curved template at the top of the guide pipes and a lower curved template at the bottom of the steel arch frame. The upper fixed steel section is placed on the upper curved template, with one end fixed in the tunnel soil, and a fixing nut connected to its outer arc surface. The lower fixed steel section is placed below the lower curved template, with one end fixed in the tunnel soil, and a fixing nut connected to its inner arc surface. Fixing bars secure the upper and lower fixed steel sections to the fixing nuts. Side templates connect the upper and lower fixed steel sections.

[0007] Preferably, the deformation control strong support structure includes a continuous arc-shaped steel plate and steel plate fixing bars; the continuous arc-shaped steel plate is set on the arch and fixed to the tunnel by the steel plate fixing bars; the continuous arc-shaped steel plate is provided with long pipe roof holes and small guide pipe holes at intervals; the long pipe roof holes and small guide pipe holes are respectively inserted through the long pipe roof and small guide pipes, and the long pipe roof and small guide pipes are respectively inserted into the tunnel.

[0008] Preferably, the anti-vacuum warning lining pouring trolley includes a trolley; a liquid level relay is provided in the lining, an arc-shaped probe fixing component is fixed to the top of the lining by fixing wire, a probe is fixed on the arc-shaped probe fixing component, and a monitoring and control box is provided inside the trolley.

[0009] According to claim 1, the complex soft rock double-layer initial support ultra-large cross-section tunnel is characterized in that the temporary invert arch deformation control structure includes an invert arch, the bottom of the tunnel is provided with an invert arch, several U-shaped positioning bars are evenly distributed in the invert arch, the U-shaped positioning bars are fitted with inherent steel profiles, and reinforcing connecting bars are welded through between the steel profiles, and the invert arch is backfilled with concrete.

[0010] Preferably, the buffer and pressure relief support system includes an interface; the soil outside the tunnel is divided into a loess layer and a soft rock layer, the interface is located between the loess layer and the soft rock layer, the tunnel arc surface is provided with a double-layer arch frame, and the buffer and pressure relief support device is set on the double-layer arch frame at the interface.

[0011] Preferably, the buffer pressure relief support device includes a lower pressure plate and an upper pressure plate; the lower pressure plate is fixed on the outer arc surface of the double-layer arch frame, and a lower soft pad layer is connected to the other side; the upper pressure plate contacts the soil outside the tunnel, and an upper soft pad layer is connected to the other side; a compression spring is provided between the lower pressure plate and the upper pressure plate.

[0012] The construction method for this complex soft rock double-layer initial support ultra-large cross-section tunnel includes the following steps:

[0013] Step 1: Fix the long pipe roof arch support system at the tunnel entrance and pour the arch between the formwork.

[0014] Step 2: Install the deformation control strong support structure on the arch, and drive the long pipe roof and small pipe inside the deformation control strong support structure into the tunnel and grout.

[0015] Step 3: After excavating a section of the tunnel, construct a double-layer arch frame and install a buffer pressure relief support device between the soil interface and the double-layer arch frame before proceeding with the subsequent tunnel excavation.

[0016] Step 4: Excavate the invert arch section, install the invert arch, backfill the invert arch with concrete, construct the lining, and then proceed with the construction of the next section of the arch wall.

[0017] Preferably, in step four, the anti-voiding early warning lining pouring trolley includes a trolley, a liquid level relay installed in the lining, several fixing wires connected to the inner arc surface of the lining, an arc-shaped probe fixing component fixed to the end of the fixing wire, the probe fixed on the arc-shaped probe fixing component, and a monitoring and control box installed inside the trolley. During the lining construction, a liquid level relay is installed in the lining, a probe is fixed on the arc-shaped probe fixing component, the arc-shaped probe fixing component is fixed to the top of the lining by fixing wires, the monitoring and control box is set on the trolley, the trolley is moved to the lining position and the end template is installed, the lining concrete is poured and vibrated, and the pouring is stopped after the monitoring and control box detects that there is concrete at all probes.

[0018] The beneficial effects of this invention are:

[0019] 1) This invention uses a long pipe shed arch support system for construction. The curved template is prefabricated in advance and can be quickly installed on the upper part of the guide pipe and the lower part of the steel arch frame during installation. It has high installation efficiency, good stability, and saves construction time.

[0020] 2) This invention uses a deformation-controlled strong support structure for construction, which is simple to operate. Long pipe roofs and small pipes are driven into the tunnel and grouting is performed inside the deformation-controlled strong support structure, which enhances the overall stability of the support structure, effectively reinforces complex soft rock geology, and ensures construction safety.

[0021] 3) This invention uses an anti-void early warning lining pouring trolley for concrete pouring. The monitoring and control box inside the trolley monitors the concrete pouring in real time, with a high degree of informatization and timely feedback, effectively ensuring the compactness of the arch concrete.

[0022] 4) This invention uses a temporary invert arch deformation control structure for construction. Several U-shaped positioning bars are used to hold the inherent steel structure inside the invert arch. Reinforcing connecting bars are welded through the steel structure, resulting in high structural strength, effectively preventing the collapse of the surrounding rock, and ensuring the safety of tunnel construction.

[0023] 5) The present invention adopts a buffer pressure relief support system for construction. A buffer pressure relief support device is installed at the interface and between the double-layer arch frame, so that the pressure at the boundary of the layered rock and soil strata can be smoothly transitioned, which can effectively solve the problem of excessive local pressure and improve the overall balance. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the long pipe shed arch support system structure;

[0025] Figure 2 yes Figure 1 Sectional view of AA;

[0026] Figure 3 This is a schematic diagram of a deformation-controlled strong support structure;

[0027] Figure 4 This is a schematic diagram of the anti-vacuum early warning lining pouring trolley structure;

[0028] Figure 5 This is a schematic diagram of the temporary invert arch deformation control structure;

[0029] Figure 6 yes Figure 5 Sectional view of the AA structure;

[0030] Figure 7 This is a schematic diagram of the buffer pressure relief support system structure;

[0031] Figure 8 This is a front view of the buffer pressure relief support device structure;

[0032] Figure 9 This is a side view of the buffer pressure relief support device structure.

[0033] Explanation of reference numerals in the attached drawings: 1-Arch foundation, 2-Steel arch frame, 3-Guide pipe, 4-Upper curved formwork, 5-Lower curved formwork, 6-Upper fixed steel, 7-Lower fixed steel, 8-Fixing reinforcement, 9-Fixing nut, 10-Side formwork, 11-Tunnel, 12-Arch sleeve, 13-Connected arc-shaped steel plate, 14-Steel plate fixing reinforcement, 15-Long pipe shed hole, 16-Long pipe shed, 17-Small guide pipe hole, 18-Small guide pipe, 19-Trolley, 20-Liner, 21-Liquid level relay Electrical components, 22-probe, 23-arc probe fixing piece, 24-fixing wire, 25-monitoring controller, 26-inverted arch, 27-U-shaped positioning frame, 28-section steel, 29-reinforcing connecting bar, 30-concrete, 31-loess layer, 32-soft rock layer, 33-interface, 34-double-layer arch frame, 35-buffered pressure relief support device, 36-lower pressure plate, 37-lower soft pad layer, 38-compression spring, 39-upper soft pad layer, 40-upper pressure plate. Detailed Implementation

[0034] The present invention will be further described below with reference to embodiments. The description of the embodiments below is only for the purpose of helping to understand the present invention. It should be noted that those skilled in the art can make several modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0035] Example 1

[0036] As one example, a complex soft rock double-layer initial support ultra-large cross-section tunnel is proposed, such as... Figures 1 to 9 As shown, the system includes a long pipe roof arch support system, a deformation control strong support structure, an anti-voiding early warning lining pouring trolley, a temporary invert arch deformation control structure, and a buffer pressure relief support system. The long pipe roof arch support system is fixed in the soil at the entrance of tunnel 11, with both ends fixed to the ground. Templates are provided on both the inner and outer arc surfaces of the long pipe roof arch support system for pouring the arch 12. The deformation control strong support structure is located on the arch 12. The deformation control strong support structure contains long pipe roofs 16 and small guide pipes 18, which are inserted into tunnel 11. The anti-voiding early warning lining pouring trolley is located inside tunnel 11, and the arc surface of tunnel 11 is filled with lining 20. An invert arch 26 is provided at the bottom of tunnel 11 and backfilled with concrete 30. The contact surface between different soil types outside tunnel 11 is an interface 33. Tunnel 11 has a double-layer arch frame 34. The interface 33 and the double-layer arch frame 34... A buffer pressure relief support device 35 is provided between the sections; the long pipe shed arch support system includes an arch frame foundation 1, a steel arch frame 2, an upper fixed steel section 6, and a lower fixed steel section 7; the arch frame foundation 1 is fixed on the ground, the two ends of the steel arch frame 2 are fixed on the arch frame foundation 1, the steel arch frame 2 is provided with multiple guide pipes 3, the upper part of the guide pipes 3 is provided with an upper curved template 4, and the lower part of the steel arch frame 2 is provided with a lower curved template 5; the upper fixed steel section 6 is set on the upper curved template 4, one end is fixed in the soil of the tunnel 11, and the outer arc surface is connected with a fixing nut 9; the lower fixed steel section 7 is set at the lower part of the lower curved template 5, one end is fixed in the soil of the tunnel 11, and the inner arc surface is connected with a fixing nut 9; the fixing bar 8 fixes the upper fixed steel section 6 and the lower fixed steel section 7 through the fixing nut 9; a side template 10 is connected between the upper fixed steel section 6 and the lower fixed steel section 7.

[0037] like Figure 3As shown, the deformation control strong support structure includes a conjoined arc-shaped steel plate 13, steel plate fixing ribs 14, long pipe roof holes 15, long pipe roof 16, small guide pipe holes 17, and small guide pipes 18. The conjoined arc-shaped steel plate 13 is set on the arch 12 and fixed to the tunnel 11 by the steel plate fixing ribs 14. The long pipe roof 16 and small guide pipes 18 pass through the long pipe roof holes 15 and the small guide pipe holes 17 and are driven into the tunnel 11. Specifically, the conjoined arc-shaped steel plate 13 is provided with long pipe roof holes 15 and small guide pipe holes 17 at intervals. The long pipe roof holes 15 and the small guide pipe holes 17 are respectively penetrated by the long pipe roof 16 and the small guide pipes 18, and the long pipe roof 16 and the small guide pipes 18 are respectively inserted into the tunnel 11.

[0038] Example 2

[0039] As another embodiment, this embodiment two proposes a more specific complex soft rock double-layer initial support ultra-large cross-section tunnel based on embodiment one.

[0040] like Figure 4 As shown, the anti-vacuum early warning lining pouring trolley includes a trolley 19, a liquid level relay 21, a probe 22, an arc-shaped probe fixing component 23, a fixing wire 24, and a monitoring and control box 25; the liquid level relay 21 is provided in the lining 20, the top of the lining 20 is fixed with the arc-shaped probe fixing component 23 by the fixing wire 24, the probe 22 is fixed on the arc-shaped probe fixing component 23, and the monitoring and control box 25 is provided inside the trolley 19.

[0041] like Figure 5 and Figure 6 As shown, the temporary invert arch deformation control structure includes an invert arch 26, U-shaped positioning bars 27, steel sections 28, reinforcing connecting bars 29, and concrete 30; the bottom of the tunnel 11 is provided with an invert arch 26, and several U-shaped positioning bars 27 are evenly distributed inside the invert arch 26. The steel sections 28 are fixed inside the U-shaped positioning bars 27, and reinforcing connecting bars 29 are welded through between the steel sections 28. The invert arch 26 is backfilled with concrete 30.

[0042] like Figure 7 As shown, the buffer pressure relief support system includes an interface 33, a double-layer arch frame 34, and a buffer pressure relief support device 35; the soil outside the tunnel 11 is divided into a loess layer 31 and a soft rock layer 32, the interface 33 is located between the loess layer 31 and the soft rock layer 32, the arc surface of the tunnel 11 is provided with a double-layer arch frame 34, and the buffer pressure relief support device 35 is set on the double-layer arch frame 34 at the interface 33.

[0043] like Figure 8 and Figure 9As shown, the buffer pressure relief support device 35 includes a lower pressure plate 36, a lower soft pad layer 37, a compression spring 38, an upper soft pad layer 39, and an upper pressure plate 40. The lower soft pad layer 37 and the upper soft pad layer 39 respectively contact the lower pressure plate 36 and the upper pressure plate 40. Specifically, the lower pressure plate 36 is fixed on the outer arc surface of the double-layer arch frame 34, and the lower soft pad layer 37 is connected to the other side. The upper pressure plate 40 contacts the soil outside the tunnel 11, and the upper soft pad layer 39 is connected to the other side. A compression spring 38 is provided between the lower pressure plate 36 and the upper pressure plate 40.

[0044] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 1 can be referred to each other, and will not be repeated in this application.

[0045] Example 3

[0046] As another embodiment, this third embodiment, based on the second embodiment, proposes a construction method for a complex soft rock double-layer initial support ultra-large cross-section tunnel, such as... Figures 1 to 9 As shown, it includes the following steps:

[0047] Step 1: Fix the long pipe shed arch support system at the entrance of Tunnel 11 and pour the arch 12 between the formwork. Specifically, thoroughly understand the construction process, give instructions to the on-site technical personnel, and bring relevant materials and equipment to the site. Construct the arch frame foundation 1 at the tunnel entrance. Fix both ends of the steel arch frame 2 to the arch frame foundation 1. Install multiple guide pipes 3 on the steel arch frame 2. Set the upper curved template 4 on the upper part of the guide pipes 3. Set the lower curved template 5 on the lower part of the steel arch frame 2. Set the upper fixed steel 6 on the upper curved template 4, with one end fixed in the soil at the entrance of Tunnel 11. Set the lower fixed steel 7 on the lower curved template 5, with one end fixed in the soil at the entrance of Tunnel 11. Fix the upper fixed steel 6 and the lower fixed steel 7 with fixing nuts 9. Pour concrete and remove the formwork after the required strength is reached.

[0048] Step 2: Install the deformation control strong support structure on the arch 12. The long pipe roof 16 and small guide pipe 18 inside the deformation control strong support structure are driven into the tunnel 11 and grouted. Specifically, install the integrated arc-shaped steel plate 13 on the arch 12 and fix it to the tunnel 11 by the steel plate fixing bar 14. The long pipe roof hole 15 and small guide pipe hole 17 are set at intervals on the integrated arc-shaped steel plate 13. The long pipe roof 16 and small guide pipe 18 are driven into the tunnel 11 through the long pipe roof hole 15 and small guide pipe hole 17 and grouted to complete the support construction.

[0049] Step 3: After excavating a section of the tunnel, construct a double-layer arch frame 34 and install a buffer pressure relief support device 35 between the soil interface 33 and the double-layer arch frame 34 before proceeding with the subsequent excavation of the tunnel 11. Specifically, assemble the buffer pressure relief support device 35, fix the lower pressure plate 36 on the double-layer arch frame 34, set the lower soft pad layer 37 and the upper soft pad layer 39 on the lower pressure plate 36 and the upper pressure plate 40, and set the compression spring 38 between the lower pressure plate 36 and the upper pressure plate 40. Excavate the tunnel, construct the double-layer arch frame 34 after excavating a section, and install the buffer pressure relief support device 35 at the interface 33 between the loess layer 31 and the soft rock layer.

[0050] Step 4: Excavate section 26 of the invert arch, install section 26 of the invert arch, backfill section 26 with concrete 30, construct section 20 of the lining, and proceed with the construction of the next section of the arch wall.

[0051] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 2 can be referred to each other, and will not be repeated in this application.

[0052] Example 4

[0053] As another embodiment, this fourth embodiment, based on the third embodiment, proposes a construction method for a complex soft rock double-layer initial support ultra-large cross-section tunnel, such as... Figures 1 to 9 As shown, it includes the following steps:

[0054] Step 1: Fix the long pipe roof arch support system at the entrance of tunnel 11, and pour the arch 12 between the formwork.

[0055] Step 2: Install the deformation control strong support structure on the arch 12. Drive the long pipe shed 16 and small pipe 18 inside the deformation control strong support structure into the tunnel 11 and grout.

[0056] Step 3: After excavating a section of the tunnel, construct a double-layer arch frame 34 and install a buffer pressure relief support device 35 between the soil interface 33 and the double-layer arch frame 34 before proceeding with the subsequent excavation of the tunnel 11.

[0057] Step 4: Excavate section 26 of the invert arch, install invert arch 26, backfill invert arch 26 with concrete 30, construct lining 20, and proceed with the construction of the next section of the arch wall; specifically, during the construction of section 26 of the invert arch, install U-shaped positioning bars 27 at certain intervals, erect steel sections 28 on the U-shaped positioning bars 27, weld reinforcing connecting bars 29 on multiple adjacent steel sections 28, backfill invert arch 26 with concrete 30; tie the reinforcing bars of lining 20, install level relay 21 in lining 20, and fix probe 22 to the arc-shaped probe fixture. On the fixed part 23, the arc-shaped probe fixing part 23 is fixed to the top of the lining 20 by the fixing wire 24. The monitoring control box 25 is set on the trolley 19. The trolley 19 is moved to the position where concrete needs to be poured, and the end formwork is installed. Concrete is poured and vibrated. After the monitoring control box 25 detects that there is concrete at all probes 22, the pouring stops. After the concrete strength meets the requirements, the formwork is removed and the next section of the arch wall is constructed. The auxiliary works are constructed. After all the works are completed and accepted, the relevant equipment is removed from the site.

[0058] It should be noted that the parts in this embodiment that are the same as or similar to those in Embodiment 3 can be referred to each other, and will not be repeated in this application.

[0059] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

Claims

1. A complex soft rock double-layer primary support super-large cross-section tunnel, characterized in that, The application relates to a long-pipe-shed-arch supporting system, a deformation control strong supporting structure, a void-preventing early-warning lining pouring trolley, a temporary inverted-arch deformation control structure and a buffer pressure-allowing supporting system. The long-pipe-shed-arch supporting system is fixed in a tunnel portal soil body, two ends of the long-pipe-shed-arch supporting system are fixed on the ground, and the inner and outer arc surfaces of the long-pipe-shed-arch supporting system are provided with formworks for pouring the arch; the deformation control strong supporting structure is arranged on the arch; the deformation control strong supporting structure is internally provided with long-pipe sheds and small guide pipes and is inserted into the tunnel. The void-preventing early-warning lining pouring trolley is located in the tunnel, and the tunnel arc surface is poured with lining; the tunnel bottom is provided with an inverted arch and is backfilled with concrete; different soil contact surfaces outside the tunnel are division surfaces, the tunnel is provided with double-layered arch frames, and the buffer pressure-allowing supporting device is arranged between the division surfaces and the double-layered arch frames. The long-pipe-shed-arch supporting system comprises an arch frame foundation, a profile steel arch frame, an upper fixed profile steel and a lower fixed profile steel; the arch frame foundation is fixed on the ground, two ends of the profile steel arch frame are fixed on the arch frame foundation, a plurality of guide pipes are arranged on the profile steel arch frame, upper curved formworks are arranged on the upper portions of the guide pipes, and lower curved formworks are arranged on the lower portions of the profile steel arch frame; the upper fixed profile steel is arranged on the upper curved formworks, one end of the upper fixed profile steel is fixed in the tunnel soil body, and a fixed nut is connected to the outer arc surface; the lower fixed profile steel is arranged on the lower curved formworks, one end of the lower fixed profile steel is fixed in the tunnel soil body, and a fixed nut is connected to the inner arc surface; a fixed rib is arranged to fix the upper fixed profile steel and the lower fixed profile steel through the fixed nuts; and side formworks are arranged between the upper fixed profile steel and the lower fixed profile steel.

2. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The deformation control strong supporting structure comprises a connected arc-shaped steel plate and a steel plate fixed rib; the connected arc-shaped steel plate is arranged on the arch and is fixed on the tunnel through the steel plate fixed rib, the connected arc-shaped steel plate is provided with long-pipe-shed holes and small guide pipe holes at intervals, the long-pipe-shed holes and the small guide pipe holes are respectively penetrated by long-pipe sheds and small guide pipes, and the long-pipe sheds and the small guide pipes are respectively inserted into the tunnel.

3. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The void-preventing early-warning lining pouring trolley comprises a trolley; a liquid level relay is arranged in the lining, an arc-shaped probe fixing piece is fixed on the top of the lining through a fixed wire, a probe is fixed on the arc-shaped probe fixing piece, and a monitoring control box is arranged in the trolley.

4. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The temporary inverted-arch deformation control structure comprises an inverted arch, the tunnel bottom is provided with the inverted arch, a plurality of U-shaped positioning ribs are uniformly distributed in the inverted arch, profile steels are clamped in the U-shaped positioning ribs, and reinforcing connecting ribs are welded between the profile steels, and the inverted arch is backfilled with concrete.

5. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The buffer pressure-allowing supporting system comprises a division surface; the soil outside the tunnel is divided into a loess layer and a soft rock layer, the division surface is located between the loess layer and the soft rock layer, the tunnel arc surface is provided with double-layered arch frames, and the buffer pressure-allowing supporting device is arranged on the double-layered arch frames at the division surface.

6. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The buffer pressure-allowing supporting device comprises a lower pressure plate and an upper pressure plate; the lower pressure plate is fixed on the outer arc surface of the double-layered arch frame, and the other side of the lower pressure plate is connected with a lower soft cushion layer; the upper pressure plate contacts the soil outside the tunnel, and the other side of the upper pressure plate is connected with an upper soft cushion layer; a compression spring is arranged between the lower pressure plate and the upper pressure plate.

7. The complex soft rock double-layer initial support super-large cross-section tunnel according to claim 1, characterized in that, The application further relates to a tunnel construction method.

8. The construction method of the complex soft rock double-layer primary support super-large cross-section tunnel according to claim 1, characterized in that, Step one: fixing the long-pipe-shed-arch supporting system at the tunnel portal and pouring the arch between the formworks. ​ Step two, install the deformation control strong support structure on the arch, the long pipe shed and small guide pipe in the deformation control strong support structure are punched into the tunnel and grouted; Step three, excavate a section of the hole body, then construct the double-layer arch frame, install the buffer yielding support device between the double-layer arch frame and the soil interface, and then excavate the subsequent hole body of the tunnel; Step four, excavate the inverted arch section, backfill the inverted arch with concrete after installing the inverted arch, then construct the lining, and then construct the next section of the arch wall.

9. The construction method of a complex soft rock double-layer primary support super-large cross-section tunnel according to claim 8, characterized in that, In step four, the anti-disengagement early warning lining pouring trolley comprises a trolley, a liquid level relay is arranged in the lining, a plurality of fixed wires are connected to the inner arc surface of the lining, an arc-shaped probe fixing piece is fixed to the end of the fixed wire, a probe is fixed to the arc-shaped probe fixing piece, and a monitoring control box is arranged in the trolley; during the lining construction, the liquid level relay is arranged in the lining, the probe is fixed to the arc-shaped probe fixing piece, the arc-shaped probe fixing piece is fixed to the top of the lining through the fixed wire, the monitoring control box is arranged on the trolley, the trolley is moved to the lining position and the end template is installed, the lining concrete is poured and vibrated, and the pouring is stopped after the monitoring control box monitors that there is concrete at all the probes.

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