Construction method of tunnel obliquely penetrating existing anti-slide pile

Abstract

The application discloses a tunnel oblique-penetrating existing anti-slide pile construction method, comprising the following steps: S1, preparation before construction; S2, replacing the existing anti-slide pile with a replacement structure to reinforce the anti-slide pile slope; the replacement structure comprises a cast-in-place pile and a buttressed retaining wall; S3, tunnel construction; including existing anti-slide pile cutting, arch construction, advanced large pipe shed construction, arch protection construction, and dark hole excavation by using the CRD method. The tunnel oblique-penetrating existing anti-slide pile construction method can reduce the influence of breaking the existing anti-slide pile on the slope stability during the tunnel construction process to the maximum extent, and guarantee the safety and stability of the slope anti-slide system and the tunnel structure during the tunnel construction process; and the cast-in-place pile in the replacement structure can replace the foundation of the existing anti-slide pile, and together with the buttressed retaining wall, forms a stress system to bear the side pressure and sliding force of the slope.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel construction, in particular to a construction method for tunnel oblique penetration of existing anti-slide piles. BACKGROUND

[0002] Anti-slide piles are common side slope reinforcement structures, and the construction of mountainous highways and railway tunnels inevitably encounters anti-slide piles. Anti-slide piles play a crucial role in the safety and stability of structures. In most constructions, it is often necessary to penetrate the original structure or the original reinforcement structure, and for such cases, how to protect the original structure without damaging its safety or even ensuring its normal use during tunnel construction has become a major problem. If not properly protected, the tunnel construction process may threaten the safety and stability of the side slope, causing significant economic losses and casualties. Therefore, the invention of a tunnel penetration anti-slide pile construction method has important practical significance for the design and construction of this type of tunnel.

[0003] In the prior art, avoiding anti-slide pile structures or re-strengthening the original structure is a common construction method, but this method increases the construction period and construction cost, and sometimes increases the construction difficulty; Chinese patent No. 201520714971.2 discloses a reinforcement structure for a tunnel that penetrates a landslide, which is composed of an anti-slide pile and its additional structure, reducing the stress on the tunnel lining structure, ensuring the stability of the overall tunnel structure, and allowing the tunnel to be located in the reinforced area without being affected by the landslide. However, this structure has limitations, and the tunnel described in this technology penetrates the soil under the anti-slide pile and is not affected by the anti-slide pile, which is not common and does not have good applicability. SUMMARY

[0004] To solve the above problems, the present application provides a construction method for tunnel oblique penetration of existing anti-slide piles, which minimizes the impact of breaking existing anti-slide piles on the stability of the side slope during tunnel construction and ensures the safety and stability of the side slope anti-slide system and the tunnel structure during tunnel construction.

[0005] To achieve the above purpose, the technical solution adopted by the present application is as follows:

[0006] A construction method for tunnel oblique penetration of existing anti-slide piles, characterized in that it comprises the following steps:

[0007] S1: preparation before construction;

[0008] S2: replace the existing anti-slide piles with replacement structures and reinforce the anti-slide pile side slope; the replacement structure includes cast-in-place piles and buttressed retaining walls;

[0009] S3: tunnel construction.

[0010] Further, the specific operation of step S1 comprises the following steps,

[0011] S101: construction arrangement; complete the arrangement of the site and the construction of the construction road, improve the construction conditions; determine the water supply source, and lay out the construction water route; newly build a box-type transformer and a standby diesel generator;

[0012] S102: construction preparation; including completing "three connections and one leveling", material stacking site, installation and debugging preparation work of tools and instruments; according to the construction design drawing, rechecking the earth filling range and the pile position of the cast-in-place pile, and carrying out measurement and sample laying;

[0013] S103: earth filling; after measurement and sample laying, filling the temporary working platform, and the rolling follows the principle of "light first, heavy later, both sides first, middle later, static pressure first, vibration pressure later". The rolling is divided into initial pressure, repeated pressure and final pressure.

[0014] Further, the specific operation of step S2 comprises the following steps,

[0015] S201: rotary drilling cast-in-place pile construction;

[0016] S202: detection of cast-in-place pile; using the combination of low strain and ultrasonic complete detection, carrying out core sampling detection of cast-in-place pile;

[0017] S203: construction of buttress retaining wall.

[0018] Further, the specific operation of step S201 comprises the following steps,

[0019] S2011: arranging and laying out the pile position of the cast-in-place pile on both sides of the tunnel lining; the pile position of the cast-in-place pile is in a trapezoidal distribution;

[0020] S2012: burying the casing at the pile position of the cast-in-place pile according to the construction sequence of "first inclined, then horizontal, up and down staggered, and hole spacing";

[0021] S2013: drilling a hole in the casing, taking out the soil in the casing, then placing the steel reinforcement cage frame and the guide pipe in the casing, pouring concrete, and forming the cast-in-place pile.

[0022] Further, the specific operation of step S203 comprises the following steps,

[0023] S2031: excavating a foundation pit between the top of the cast-in-place pile, and using reinforced concrete to pour the retaining wall foundation in the foundation pit, the retaining wall foundation comprises a beam and a toe plate, the main reinforcement of the cast-in-place pile extends into the toe plate and is connected with the steel reinforcement of the toe plate, and a reinforcing bar is arranged;

[0024] S2032: pouring the wall surface plate and a plurality of buttresses on the retaining wall foundation, the wall surface plate is arranged along the mountain direction, the buttresses are in a triangular structure, and are vertically arranged with the retaining wall and the wall surface plate;

[0025] S2033: chiseling the contact surface between the existing anti-slide pile and the wall panel, and filling the gap between the existing anti-slide pile and the replacement structure with concrete together with the wall panel;

[0026] S2034: backfilling the earthwork gap between adjacent buttresses, the wall panel and the slope, and the existing anti-slide pile with foam soil, and backfilling and tamping layer by layer according to the earthwork filling requirements.

[0027] Further, the specific operation of step S3 includes the following steps,

[0028] S301: cutting off the existing anti-slide pile;

[0029] S302: arch construction;

[0030] S303: advance large pipe shed construction;

[0031] S304: arch protection construction;

[0032] S305: using the CRD method to excavate the hidden hole.

[0033] Further, the specific operation of step S301 includes the following steps,

[0034] S3011: after the strength of the replacement structure reaches the requirement and the displacement of the slope tends to be stable, excavate the soil under the heel plate, reinforce between the bored piles during excavation, and use steel mesh + sprayed concrete for reinforcement;

[0035] S3012: pre-drilling the existing anti-slide pile, and the pre-drilling position is located below the arch;

[0036] S3013: dividing the part of the anti-slide pile to be cut off into multiple sections and setting the cutting line; the first section of each pile is set at the uppermost part;

[0037] S3014: when cutting off the first section of the pile, drilling the two outermost holes according to the cutting line hole position, removing the core rod, and randomly setting temporary supports in the outermost holes; then drilling the remaining holes of the section, immediately setting temporary supports according to the first hole method after drilling is completed, respectively engaging the remaining holes, and until the cutting is completed and cut off; the cutting method of the remaining sections is the same as that of the first section;

[0038] S3015: after cutting off the first section of the pile, setting steel arch supports temporarily at the original position;

[0039] S3016: drilling holes and engaging cores in sequence according to the pile order according to the tunnel excavation contour line;

[0040] S3017: backfill the soil under the heel plate, and the soil backfill is performed within 1.0-1.5 m along the arch ring arc, and the backfill is performed by layer-by-layer filling and layer-by-layer compaction, and the backfill is used as the support of the lining.

[0041] Further, the specific operation of steps S302-S304 includes the following steps,

[0042] After the lining construction is performed, the advanced large pipe shed construction is performed according to the reserved hole position; the part where the large pipe shed cannot be constructed is replaced by a double-layer small guide pipe.

[0043] The concrete is backfilled to the heel plate and the gap between the pile and the backfill soil to form the arch protection.

[0044] Further, the specific operation of step S305 includes the following steps,

[0045] Step 1: left side advanced support;

[0046] Step 2: left upper guide pit excavation;

[0047] Step 3: left upper guide pit support;

[0048] Step 4: temporary steel column and cross support are set;

[0049] Step 5: left lower guide pit excavation;

[0050] Step 6: left lower guide pit support;

[0051] Step 7: temporary steel column is completed;

[0052] Step 8: right side advanced support;

[0053] Step 9: right upper step excavation;

[0054] Step 10: right upper step support;

[0055] Step 11: temporary steel cross support is set;

[0056] Step 12: right lower step excavation;

[0057] Step 13: right lower step support;

[0058] Step 14: inverted arch pouring;

[0059] Step 15: temporary column and support are removed;

[0060] Step 16: waterproof layer construction;

[0061] Step 17: lining construction.

[0062] The beneficial effects of the present application are:

[0063] 1. The tunnel oblique construction method of the present application can replace the function of the existing anti-slide pile by using a replacement structure before tunneling, which can minimize the impact of breaking the existing anti-slide pile on the stability of the slope during tunneling, and ensure the safety and stability of the slope anti-slide system and the tunnel structure during tunneling.

[0064] 2. The replacement structure (cast-in-place pile + buttressed retaining wall) used to replace the function of the existing anti-slide pile in the present application connects the concrete and steel between the cast-in-place pile and the buttressed retaining wall, forming a "box-type" structure, which together with the existing anti-slide pile forms a more stable first anti-slope sliding system. Based on reinforcement and treatment, the replacement structure system and the existing anti-slide pile together form a theoretical tunnel support structure, which provides a relatively stable external construction environment for the tunnel inside the box, meeting the stability and strength requirements of the tunnel oblique anti-slide pile. The tunnel oblique anti-slide pile is gradually broken as the tunnel face advances, greatly reducing the impact of breaking the anti-slide pile on the slope and surrounding soil.

[0065] 3. The present application has simple structure, reasonable design and convenient construction, effectively solving the stress conversion problem of breaking the anti-slide pile during tunneling and the construction organization problem of breaking the pile during tunneling. BRIEF DESCRIPTION OF DRAWINGS

[0066] Figure 1 The tunnel oblique construction method of the present application.

[0067] Figure 2 The plan view of the cast-in-place pile structure in the present application.

[0068] Figure 3 The plan view of the cast-in-place pile numbering in the present application.

[0069] Figure 4 The position relationship between the buttressed retaining wall and the cast-in-place pile in the present application.

[0070] Figure 5 The structure of the buttressed retaining wall in the present application.

[0071] Figure 6 The three-dimensional effect of the replacement structure in the present application.

[0072] Figure 7 The construction process of the replacement structure in the present application.

[0073] Figure 8 The schematic diagram of the large pipe shed crossing the pre-drilled hole and the engagement core cutting in the present application.

[0074] Figure 9 The schematic diagram of the single pile first section cutting body temporary support and the hole temporary support section in the present application.

[0075] Figure 10 For the invention in the plane of the arch and the arch.

[0076] Figure 11 For the invention in the CRD method construction process chart. DETAILED DESCRIPTION

[0077] In order to make those skilled in the art better understand the technical solutions of the present application, the technical solutions of the present application will be further described below in combination with the drawings and examples.

[0078] As shown in the accompanying Figure 1 A tunnel oblique construction method of existing anti-slide pile, comprising the following steps, S1: preparation before construction;

[0079] Specifically, the preparation before construction includes:

[0080] S101: construction arrangement; complete the arrangement of the site and the construction of the construction road, use the existing conditions, improve the construction conditions such as water and electricity for construction; determine the water supply source and lay out the construction water route; newly build a box-type transformer and a standby diesel generator;

[0081] S102: construction preparation; including completing the "three pass one flat" of the early stage, material storage site, installation and debugging preparation work of tools and instruments; according to the construction design drawing, review the earth filling range and the pile position of the bored pile, and measure and sample and hand over;

[0082] S103: earth filling; after measuring and sampling, fill the temporary working platform, and the rolling follows the principle of "light first, heavy later, both sides first, middle later, static pressure first, vibration pressure later", and the rolling is divided into initial pressure, repeated pressure and final pressure.

[0083] Further, step S2: replacing the existing anti-slide pile with a replacement structure to reinforce the anti-slide pile slope; specifically, the tunnel exit needs to pass out from the anti-slide pile slab wall at the lower part of the slope, the existing anti-slide pile of the slope needs to be cut off, and there are buildings in the vicinity of the side, the stability of the side slope needs to be considered, therefore, the anti-slide pile slope needs to be reinforced first. In the present application, the replacement structure includes a cast-in-place pile and a buttressed retaining wall; the construction process of the replacement structure includes:

[0084] S201: construction by using rotary drilling and cast-in-place method, rotary drilling and cast-in-place pile construction;

[0085] More specifically, S2011: arranging and sampling the cast-in-place pile position on both sides of the tunnel open cut lining; the cast-in-place pile position is distributed in a trapezoidal shape, as shown in the accompanying Figure 2 .

[0086] S2012: at the cast-in-place pile position, according to the construction sequence of "first inclined, then flat, up and down staggered, and hole spacing", bury the casing, as shown in the accompanying Figure 3The construction sequence of the bored piles shown is 2, 4, 1, 3, 5, 19, 24, 18, 23, 17, 22, 16, 21, 15, 20, 14, 12, 10, 8, 6, 13, 11, 9, 7.

[0087] S2013: drilling inside the casing, removing the soil inside the casing, then placing a reinforcement cage framework and a guide pipe inside the casing, pouring concrete, and forming a bored pile. The specific process of this operation step is: preparing mud, positioning the drilling machine, drilling, final hole, first hole cleaning detection, making and installing a reinforcement cage framework, installing a guide pipe, second hole cleaning, and pouring concrete.

[0088] Further, S202: bored pile detection; using a combination of low strain and ultrasonic wave integrity detection, bored pile core sampling detection is performed, and after the bored pile is detected to be appropriate, the next construction can be performed.

[0089] Further, S203: buttress retaining wall construction;

[0090] More specifically, S2031: excavating a foundation pit between the tops of the bored piles, and using reinforced concrete to pour a retaining wall foundation in the foundation pit, the retaining wall foundation including a beam and a toe plate, as shown in FIGS. 8 and 9. Figure 4 and FIGS. 10 and 11. Figure 5 As shown in FIGS. 8 and 9, when pouring the retaining wall foundation, the main reinforcement of the bored pile is extended into the toe plate and connected with the reinforcement of the toe plate, and a reinforcing bar is provided to ensure the overall stability of the replacement structure in subsequent construction.

[0091] S2032: pouring a wall panel and multiple buttresses on the retaining wall foundation, the wall panel being arranged along the mountain direction, and the buttresses being in a triangular structure and being arranged vertically with the retaining wall and the wall panel, as shown in FIGS. 12 and 13. Figure 6

[0092] S2033: performing a chiseling treatment on the contact surface of the existing anti-slide pile and the wall panel, and filling the gap between the existing anti-slide pile and the replacement structure with concrete poured together with the wall panel;

[0093] S2034: filling the soil gap between adjacent buttresses, the wall panel and the slope, and the existing anti-slide pile with foam soil, and backfilling layer by layer and tamping according to the soil filling requirements.

[0094] The concrete between the bored pile and the buttress retaining wall is connected with the reinforcement, forming a "box-type" structure, and together with the existing anti-slide pile, forming a more stable first anti-slope sliding system. On the basis of reinforcement and treatment, the replacement structure system and the existing anti-slide pile together form a theoretically significant tunnel support structure, providing a relatively stable external construction environment for the tunnel construction inside the box, and meeting the stability and strength requirements of the tunnel obliquely passing through the anti-slide pile.

[0095] ​The present application is about the arrangement position of the cast-in-place pile, when crossing the normal slope, the cast-in-place piles are arranged left and right to provide support for the tunnel construction and prevent the damage to the lower tunnel caused by the slope sliding; when crossing the anti-slide pile, the anti-slide pile and the cast-in-place pile on the other side form a force system; in the subsequent tunnel construction, when cutting the anti-slide pile, the displacement and deformation of the main replacement area are large, and the cast-in-place piles can be arranged in a slanting ladder shape.

[0096] The replacement structure system has clear stress mechanism, large spatial stiffness and strong integrity. The cast-in-place pile can replace the original pile foundation and form a force system with the buttressed retaining wall to bear the lateral pressure and sliding force of the slope. The two sides are backfilled with foam soil, which has good durability and low strength and basically has no effect on the stress of the replacement structure system.

[0097] Further, step S3: tunnel construction.

[0098] Specifically, S301: cutting the existing anti-slide pile;

[0099] More specifically, S3011: after the strength of the replacement structure meets the requirements and the displacement of the slope tends to be stable, the soil under the toe plate is excavated, and the reinforcement between the cast-in-place piles is carried out while excavating, and the reinforcement is carried out by using steel mesh + sprayed concrete; as shown in the accompanying Figure 7 .

[0100] S3012: Before the sleeve arch and large pipe shed are constructed, the existing anti-slide pile needs to be pre-drilled, and the pre-drilling position is located on the lower side of the sleeve arch;

[0101] Although the replacement structure has reinforced the existing anti-slide pile system, in order to reduce the disturbance to the replacement structure and the ground surface building caused by cutting the pile, the tunnel boring drill is used to drill and take the core according to the cutting line, and the specific operation is shown in the following steps.

[0102] S3013: The part to be cut of the anti-slide pile is divided into multiple sections, and the cutting line is set; the first section of each pile is set at the uppermost part; as shown in the accompanying Figure 8 , the part to be cut of the six anti-slide piles is divided into 32 sections, and 38 cutting lines are set. The first section of each pile is set at the uppermost part.

[0103] S3014: When cutting the first section of the pile, the outermost two holes are drilled according to the hole position of the cutting line, the core rod is taken out, and a temporary support is set in the outermost hole (specifically, a round wood wedge is inserted into the core hole as a temporary support, as shown in the accompanying Figure 9 ) is set; then the remaining holes of the section are drilled, and after the drilling is completed, a temporary support is set according to the first hole, and the remaining holes are drilled by engaging, until the cutting is completed and the cutting is cut off; the cutting method of the remaining sections is the same as that of the first section;

[0104] S3015: After the first section of the pile is cut off, a steel arch support is arranged at the original position to provide temporary support;

[0105] S3016: Drilling and coring in turn according to the tunnel excavation profile and the pile sequence of 4#-5#-6#, 1#-2#-3#;

[0106] S3017: Backfilling the soil under the heel plate, and the soil backfilling is performed within 1.0-1.5m along the arch arc, and the backfilling is performed according to the layer-by-layer filling and layer-by-layer compaction, and is used as the support of the sleeve arch.

[0107] Further, S302: sleeve arch construction;

[0108] S303: Advanced large pipe shed construction;

[0109] S304: Arch protection construction;

[0110] The specific operation of steps S302-S304 includes the following steps,

[0111] After the sleeve arch construction is performed, the advanced large pipe shed construction is performed according to the reserved hole position; the part where the large pipe shed cannot be constructed is replaced by a double-layer small guide pipe;

[0112] The concrete is backfilled to the heel plate and the gap between the backfilling soil and the pile to form the arch protection, as shown in the accompanying Figure 10

[0113] The sleeve arch, the advanced large pipe shed and the arch protection are combined to form the second protection structure. The replacement structure, the second protection structure and the existing anti-slide pile are combined to form a more stable stress system, which reduces the influence of the fracture of the existing anti-slide pile on the slope stability and the foundation bearing capacity.

[0114] S305: After the above construction process is completed, the CRD method is used to start the hidden hole excavation. As shown in the accompanying Figure 11 , the CRD method excavates and supports (including temporary support) in the order of left upper, left lower, right upper and right lower guide hole, and the anti-slide pile cutting body needs to be removed, crushed and transported out. Where the excavation and support reach, the temporary support wedge is pulled out, the cutting body or the original stable thick steel bar is bound by manual steel wire rope, and the excavator is matched with the loader to drag to the open area outside the working face. Specifically, the following steps are included:

[0115] Step 1: Left side advance support;

[0116] Step 2: Left upper guide hole excavation;

[0117] Step 3: Left upper guide hole support (including anchor rod, steel mesh preparation, steel frame preparation and shotcrete);

[0118] Step 4: Temporary steel column and cross brace are set up;

[0119] Step 5: Left lower guide hole excavation;

[0120] ​Step 6: Left lower guide pit support (including anchor rod, steel mesh preparation, steel frame preparation and shotcrete) ;

[0121] Step 7: Complete temporary steel column;

[0122] Step 8: Right side advance support;

[0123] Step 9: Right upper step excavation;

[0124] Step 10: Right upper step support (including anchor rod, steel mesh preparation, steel frame preparation and shotcrete) ;

[0125] Step 11: Set up temporary steel cross brace;

[0126] Step 12: Right lower step excavation;

[0127] Step 13: Right lower step support (including anchor rod, steel mesh preparation, steel frame preparation and shotcrete) ;

[0128] Step 14: Inverted arch pouring;

[0129] Step 15: Remove temporary column and support;

[0130] Step 16: Waterproof layer construction;

[0131] Step 17: Lining construction.

[0132] It should be noted that the CRD method in the present application is prior art, and the present application does not make specific elaboration, and after the left upper guide pit support and the right lower step support are completed, corresponding monitoring measurement and data processing are required.

[0133] The above shows and describes the basic principles, main features and advantages of the present application. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application, and various changes and improvements can be made without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A construction method for tunneling obliquely through an existing anti-slide pile, characterized in that, Comprise the following steps, S1: construction preparation; S2: using replacement structure to replace existing anti-slide pile, and reinforcing the anti-slide pile slope; the replacement structure comprises a cast-in-place pile and a buttress retaining wall; S3: tunnel construction; The specific operation of step S2 comprises the following steps, S201: rotary drilling cast-in-place pile construction; S202: cast-in-place pile detection; using the combination of low strain and ultrasonic wave integrity detection, the cast-in-place pile core sampling detection is carried out; S203: buttress retaining wall construction; The specific operation of step S203 comprises the following steps, S2031: excavating a foundation pit between the top of the cast-in-place pile, and using reinforced concrete to cast a retaining wall foundation in the foundation pit, the retaining wall foundation comprises a beam and a heel plate, the main reinforcement of the cast-in-place pile extends into the heel plate and is connected with the steel bars of the heel plate, and a reinforcing bar is arranged; S2032: casting a wall panel and a plurality of buttresses on the retaining wall foundation, the wall panel is arranged along the mountain direction, and the buttresses are arranged in a triangular structure and are perpendicular to the retaining wall and the wall panel; S2033: performing chiseling treatment on the contact surface between the existing anti-slide pile and the wall panel, and filling the gap between the existing anti-slide pile and the replacement structure with cast-in-place concrete together with the wall panel; S2034: filling the soil gap between the adjacent buttresses, the wall panel and the slope, and the existing anti-slide pile with foam soil, and filling and tamping layer by layer according to the soil filling requirements during the filling; The specific operation of step S3 comprises the following steps, S301: cutting off the existing anti-slide pile; S302: sleeve arch construction; S303: advance large pipe shed construction; S304: arch protection construction; S305: using the CRD method to excavate the hidden hole; The specific operation of step S301 comprises the following steps, S3011: after the strength of the replacement structure reaches the requirement and the slope displacement tends to be stable, excavating the soil under the heel plate, and reinforcing between the cast-in-place piles during the excavation, and reinforcing by using a steel mesh + sprayed concrete; S3012: pre-drilling the existing anti-slide pile, and the pre-drilling position is located on the lower side of the sleeve arch; S3013: dividing the part to be cut off of the anti-slide pile into multiple sections, and setting a cutting line; the first section of each pile is arranged at the uppermost part; S3014: when cutting off the first section of the pile, positioning according to the cutting line hole position, drilling the two outermost holes, taking out the core rod, and then setting a temporary support in the outermost hole; then drilling the remaining holes of the section of the pile, and then setting a temporary support according to the first hole after the drilling is completed, and respectively engaging the remaining holes, until the cutting is completed and cut off; the cutting method of the remaining sections is the same as that of the first section; S3015: after cutting off the first section of the pile, setting a steel arch support temporary support at the original position; S3016: drilling and engaging the core in sequence according to the pile order along the tunnel excavation contour line; S3017: backfilling the soil under the heel plate, and backfilling the soil within 1.0-1.5m along the arch curve, and backfilling and compacting layer by layer as the sleeve arch support.

2. The method according to claim 1, wherein, The specific operation of step S1 comprises the following steps, S101: construction arrangement; completing the arrangement of the site and the construction of the construction access road, improving the construction conditions; determining the water supply source, and arranging the water supply route for construction; newly building a box-type transformer and a standby diesel generator; S102: construction preparation; including the completion of "three pass one flat", material storage site, installation and debugging of tools and equipment preparation; according to the construction design drawing review earth filling range and bored pile pile position, and measurement and layout; S103: earth filling; after measurement and layout, fill the temporary working platform, and the rolling follows the principle of "first light, then heavy, first two sides, then middle, first static pressure, then vibration pressure", and the rolling is divided into initial pressure, repeated pressure and final pressure.

3. The method according to claim 2, wherein, The specific operation of step S201 includes the following steps, S2011: arranging and laying out the bored pile position on both sides of the tunnel and open cut lining; the bored pile position is in a trapezoidal distribution; S2012: burying the casing at the bored pile position according to the construction sequence of first inclined, then flat, up and down staggered, and hole spacing arrangement; S2013: drilling a hole in the casing, removing the soil in the casing, then placing the steel cage frame and guide pipe in the casing, pouring concrete, and forming a bored pile.

4. The method according to claim 1, wherein, The specific operation of steps S302~S304 includes the following steps, After the arch construction, the reserved hole position is used to perform the advanced large pipe shed construction; the part where the large pipe shed cannot be constructed is replaced by a double-layer small guide pipe; The concrete is backfilled to the heel plate and the gap between the bored pile and the backfill soil to form an arch.

5. The method according to claim 4, wherein, The specific operation of step S305 includes the following steps, Step 1: left side advance support; Step 2: left upper pilot excavation; Step 3: left upper pilot support; Step 4: supporting temporary steel column and cross brace; Step 5: left lower pilot excavation; Step 6: left lower pilot support; Step 7: complete temporary steel column; Step 8: right side advance support; Step 9: right upper step excavation; Step 10: right upper step support; Step 11: supporting temporary steel cross brace; Step 12: right lower step excavation; Step 13: right lower step support; Step 14: invert pouring; Step 15: remove temporary column and support; Step 16: waterproof layer construction; Step 17: lining construction.

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