Ultra-thin culvert top soil covering support construction structure and construction method

Abstract

The invention relates to an ultra-thin culvert top soil covering support construction structure which comprises a frame bridge composed of door frame columns and door frame beams, box culvert guide rollers are arranged on the door frame beams and used for guiding when a box culvert is pushed, steel floral tubes are driven into the three sides of the frame bridge to form a tube shed, and ultra-thin soil covering on the upper portion of the box culvert is supported. A hole cleaning pipe is arranged in the steel floral pipe, a plurality of reinforcing inserting rods perpendicular to the axis of the hole cleaning pipe are evenly distributed on the side wall of the steel floral pipe in a penetrating mode, and a plurality of variable-diameter ejector blocks are arranged outside the hole cleaning pipe. The hole cleaning pipe is jacked in the axial direction of the steel floral pipe, and the variable-diameter jacking block pushes the reinforcing inserting rod to expand outwards to be inserted into a foundation. Under the condition of a shallow covering soil layer on the culvert top, the stability of an upper roadbed can be effectively protected, and the phenomena of fracture, collapse and the like caused by the movement of the pavement along with the box culvert are prevented.

Description

Technical Field

[0001] The invention relates to the technical field of underpass highway construction, and in particular to an ultra-thin culvert top soil covering support construction structure and a construction method. Background Art

[0002] With the acceleration of urbanization, the development and utilization of underground space has become more and more extensive, especially in the construction of underground passages under urban trunk roads, and the box culvert jacking construction technology has been widely used. However, in the actual construction process, due to the complex geological conditions, especially in the case of shallow overburden, how to ensure the stability of the roadbed during the box culvert jacking process has become a challenge.

[0003] During the construction of the box culvert under the highway, when the soil covering the top of the culvert is weak, if the jacking construction is not handled properly, the road surface may move with the box culvert, further causing problems such as road rupture or collapse, affecting or even blocking the normal traffic of the Lanhai Expressway.

[0004] At present, the traditional pipe shed support technology often uses the construction process of guiding drill to locate the drilling hole and pull back the pipe. Although this method can achieve the positioning and laying of the pipe shed to a certain extent, it is easy to cause the hole to collapse, especially when the cover soil layer is thin, which can easily cause the settlement of the highway road surface and threaten driving safety. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an ultra-thin culvert top covering soil support construction structure and construction method, which can effectively protect the stability of the upper roadbed under the condition of a shallow covering soil layer on the culvert top and prevent the road surface from breaking, collapsing, etc. caused by the movement of the box culvert.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: an ultra-thin culvert top soil covering support construction structure, including a frame bridge composed of a door frame column and a door frame beam, a box culvert guide roller is provided on the door frame beam for guiding the box culvert when advancing, and steel flower pipes are driven into the three sides of the frame bridge to form a pipe shed to realize the support of the ultra-thin soil covering on the upper part of the box culvert; A hole cleaning pipe is arranged inside the steel flower pipe, a plurality of reinforcing rods perpendicular to the axis of the hole cleaning pipe are evenly distributed on the side wall of the steel flower pipe, and a plurality of variable-diameter top blocks are arranged outside the hole cleaning pipe; The hole cleaning pipe is pushed in along the axial direction of the steel flower pipe, so that the variable-diameter top block pushes the reinforcement plug rod to expand outward and be inserted into the foundation.

[0007] In a preferred solution, a wedge-shaped drill bit is provided on the drilling end of the steel flower pipe, and the wedge-shaped drill bit is connected to the display screen on site through a wire; A wire connecting the wedge-shaped drill bit and the display screen is arranged through the hole cleaning pipe.

[0008] In a preferred solution, the two ends of the hole cleaning pipe are open, and two channels are provided in the hole cleaning pipe, namely a liquid through hole and a wire through hole; A spray hole is arranged on the side wall of one end of the steel flower tube close to the wedge-shaped drill bit.

[0009] In a preferred solution, the variable diameter top block includes a cylindrical section and a truncated cone section, the diameter of the cylindrical section is the same as the inner diameter of the hole cleaning pipe, and the narrow end diameter of the truncated cone section is the same as the outer diameter of the hole cleaning pipe; The variable diameter top block is provided with a plurality of pouring holes distributed in an annular direction, extending from the end surface of the cylindrical section at one end to the arc surface of the truncated cone section.

[0010] In a preferred solution, a guide cylinder is provided on the side wall of the steel flower tube, and the reinforcing rod is inserted into the guide cylinder; The end of the reinforcing rod located inside the steel flower tube is an inclined surface, the inclined surface contacts the reducer top block, and the end located outside the steel flower tube is a cone head; A grouting channel extending from the inclined surface to the cone head is arranged inside the reinforcement plug rod.

[0011] In a preferred solution, a limiting tooth is provided at the port of the guide cylinder, and a vertical strip-shaped limiting groove is provided on the side wall of the reinforcement plug rod. The limiting tooth cooperates with the limiting groove to realize axial limiting of the reinforcement plug rod.

[0012] In a preferred solution, the conical head of the reinforcing plug rod is provided with a plurality of side slurry outlet holes located on the conical surface, and the conical top of the conical head is provided with an end slurry outlet hole; The grouting channel is connected to the side grouting hole and the end grouting hole.

[0013] In a preferred solution, a blocking block is provided on one end of the hole cleaning pipe located inside the steel flower pipe, and the diameter of the blocking block is the same as the inner diameter of the steel flower pipe.

[0014] In a preferred solution, during the drilling process of the steel flower pipe, the cleaning liquid is injected from the liquid hole in the hole cleaning pipe, and injected into the supporting borehole through the injection hole and the spray hole on the variable diameter top block to achieve hole cleaning; After the hole cleaning pipe is pushed forward, the consolidation mortar is injected from the steel flower pipe, and is injected into the soil around the supporting borehole through the steel flower pipe and the pouring holes on the variable diameter top block, and at the same time, it flows into the hole through the pouring holes on the variable diameter top block to the area where the next variable diameter top block is located.

[0015] The construction method based on the above-mentioned ultra-thin culvert top soil covering support construction structure specifically includes the following steps: 1) Use the steel pipe as the drill rod and drive it along the guide pipe on the door frame column and door frame beam; 2) The steel pipe is driven in rotation, and the pitch angle and direction of the wedge drill bit are monitored in real time through the display screen during the driving process, and the drilling direction of the steel pipe is adjusted according to the pitch angle and direction of the wedge drill bit; 3) During the drilling process, mud is continuously pumped into the hole cleaning pipe through a mud pump. The mud is ejected from the spray hole under high pressure and cuts the soil. The wedge-shaped drill bit performs repairable cutting on the soil during the rotation and jacking process, forming a supporting borehole with a diameter larger than the steel flower pipe; 4) After the jacking construction is in place, the hole cleaning pipe is pushed in along the axial direction of the steel pipe, so that the variable-diameter jacking block pushes the reinforcement rod until it is inserted into the soil; 5) Seal the mouth of the steel tube and pour mortar into the mouth of the steel tube. The mortar is injected into different areas through the pouring holes in the steel tube, and then injected into the surrounding soil through the grouting channel on the reinforcement rod to form a mortar consolidation body, thus completing the reinforcement of the culvert top soil; In the step 2), when the angle of the wedge drill bit is lower than the designed trajectory angle, the wedge drill bit is turned to face the inclined surface downward, at which time the rotation is stopped and the drill bit is directly pushed forward. The wedge drill bit has an upward movement tendency due to the reaction force of the soil layer, and the drilling angle changes upward to achieve the purpose of deviation correction, and the drill bit continues to rotate and move forward until the angle reaches the design requirement; The deviation in each direction is corrected by the above method; In the step 3), the original stratum debris is mixed with the mud and flows out from the gap between the steel pipe wall and the soil until it flows to the orifice, and the shed pipe continues to move forward in this cycle.

[0016] The ultra-thin culvert top soil covering support construction structure and construction method provided by the present invention have the following beneficial effects by adopting the above structure and method: (1) The present invention increases the friction between the pipe shed and the foundation by arranging a hole cleaning pipe and a variable-diameter top block in the steel flower pipe and inserting a reinforcing rod into the foundation, thereby enhancing the stability of the overall support structure and reducing the risk of pipe shed failure caused by vehicle vibration and changes in roadbed stress during construction. (2) The construction method provided by the present invention eliminates the need for positioning pipes and guide connectors by directly driving the shed pipes in and correcting their deviations in real time, thereby simplifying the construction process, shortening the construction period, and improving the construction efficiency. (3) After the jacking construction is completed, mortar is poured into the steel tube and then injected into the surrounding soil through the pouring holes to form a mortar consolidation body. On the one hand, it can strengthen the strength of the roadbed above and reduce the risk of collapse caused by driving pressure and vibration. On the other hand, it also enhances the integrity and stability of the support structure and ensures the quality of the project. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 It is a schematic diagram of the construction cross-section structure of the present invention.

[0018] Figure 2This is a schematic diagram of the overall structure of the present invention when performing drilling operations.

[0019] Figure 3 It is a schematic diagram of the structure after the drilling operation is completed in the present invention.

[0020] Figure 4 It is a schematic diagram of the reinforcing rod structure of the present invention.

[0021] Figure 5 It is a schematic diagram of the steel flower tube structure of the present invention.

[0022] Figure 6 It is a schematic diagram of the hole cleaning pipe structure of the present invention.

[0023] In the figure: box culvert 1, support drilling hole 2, steel flower pipe 3, door frame column 4, door frame beam 5, box culvert guide roller 6, wedge drill bit 7, hole cleaning pipe 8, liquid hole 801, wire hole 802, reducer top block 9, injection hole 901, guide cylinder 10, limit tooth 1001, reinforcement plug rod 11, limit groove 111, inclined surface 112, cone head 113, grouting channel 12, side slurry outlet hole 13, end slurry outlet hole 14, display screen 15, spray hole 16, block 17. DETAILED DESCRIPTION

[0024] Embodiment 1: like Figure 1-6 In the invention, an ultra-thin culvert top soil covering support construction structure comprises a frame bridge composed of a door frame column 4 and a door frame beam 5. The door frame beam 5 is provided with a box culvert guide roller 6 for guiding the box culvert 1 when it is pushed forward. Steel flower pipes 3 are driven into the three sides of the frame bridge to form a pipe shed, so as to realize the support of the ultra-thin soil covering on the upper part of the box culvert 1. A hole cleaning pipe 8 is arranged inside the steel flower pipe 3, and a plurality of reinforcing rods 11 perpendicular to the axis of the hole cleaning pipe 8 are evenly distributed on the side wall of the steel flower pipe 3, and a plurality of variable-diameter top blocks 9 are arranged outside the hole cleaning pipe 8; The hole cleaning pipe 8 is pushed in along the axial direction of the steel flower pipe 3, so that the variable-diameter top block 9 pushes the reinforcement plug rod 11 to expand outward and be inserted into the foundation.

[0025] In a preferred solution, a wedge-shaped drill bit 7 is provided on the drilling end of the steel flower tube 3, and the wedge-shaped drill bit 7 is connected to the display screen 15 on site through a wire; The wire connecting the wedge drill bit 7 and the display screen 15 is arranged through the hole cleaning pipe 8.

[0026] In a preferred embodiment, the two ends of the hole cleaning tube 8 are open, and two channels are provided in the hole cleaning tube 8, namely, a liquid through hole 801 and a wire through hole 802; A spray hole 16 is provided on the side wall of one end of the steel flower tube 3 close to the wedge drill bit 7 .

[0027] In a preferred embodiment, the variable diameter top block 9 includes a cylindrical section and a truncated cone section, the diameter of the cylindrical section is the same as the inner diameter of the hole cleaning tube 8, and the narrow end diameter of the truncated cone section is the same as the outer diameter of the hole cleaning tube 8; The variable diameter top block 9 is provided with a plurality of injection holes 901 distributed in an annular direction and extending from the end surface of the cylindrical section at one end to the arc surface of the truncated cone section.

[0028] In the preferred solution, a guide cylinder 10 is provided on the side wall of the steel flower tube 3, and a reinforcing rod 11 is inserted into the guide cylinder 10; The end of the reinforcing rod 11 located inside the steel tube 3 is a slope 112, the slope 112 contacts the reducer top block 9, and the end located outside the steel tube 3 is a cone head 113; The reinforcing rod 11 has a grouting channel 12 extending from the inclined surface 112 to the cone head 113 inside.

[0029] In a preferred embodiment, a limiting tooth 1001 is provided at the end of the guide cylinder 10 , and a vertical strip-shaped limiting groove 111 is provided on the side wall of the reinforcing rod 11 . The limiting tooth 1001 cooperates with the limiting groove 111 to achieve axial limiting of the reinforcing rod 11 .

[0030] In a preferred embodiment, the cone head 113 of the reinforcing plug rod 11 is provided with a plurality of side slurry outlet holes 13 located on the cone surface, and the cone top of the cone head 113 is provided with an end slurry outlet hole 14; The grouting channel 12 is connected to the side grouting hole 13 and the end grouting hole 14.

[0031] In a preferred solution, a blocking block 17 is provided on one end of the hole cleaning pipe 8 located inside the steel flower pipe 3 , and the diameter of the blocking block 17 is the same as the inner diameter of the steel flower pipe 3 .

[0032] In the preferred solution, during the drilling process of the steel flower pipe 3, the cleaning liquid is injected from the liquid hole 801 in the hole cleaning pipe 8, and is injected into the supporting borehole 2 through the injection hole 901 and the spray hole 16 on the variable diameter top block 9 to achieve hole cleaning; After the hole cleaning pipe 8 is pushed forward, the consolidation mortar is injected from the steel flower pipe 3, and injected into the soil around the supporting borehole 2 through the steel flower pipe 3 and the pouring holes 901 on the variable diameter top block 9, and at the same time, it flows into the hole through the pouring holes 901 on the variable diameter top block 9 to the area where the next variable diameter top block 9 is located.

[0033] Embodiment 2: like Figure 2 , 3 As shown, the construction method of the ultra-thin culvert top soil covering support construction structure based on Example 1 specifically includes the following steps: 1) Use the steel flower tube 3 as the drill rod and drive it along the guide tube on the door frame column 4 and the door frame beam 5; 2) The steel flower pipe 3 is driven in rotation, and during the driving process, the pitch angle and direction of the wedge drill bit 7 are monitored in real time through the display screen 15, and the drilling direction of the steel flower pipe 3 is adjusted according to the pitch angle and direction of the wedge drill bit 7; 3) During the drilling process, mud is continuously pumped into the hole cleaning pipe 8 by a mud pump, and the mud is ejected from the spray hole 16 by high pressure and cuts the soil. The wedge drill bit 7 performs repair cutting on the soil during the rotation and jacking process, forming a support borehole 2 with a diameter larger than the steel flower pipe 3; 4) After the jacking construction is in place, the hole cleaning pipe 8 is jacked in the axial direction of the steel flower pipe 3, so that the variable-diameter jacking block 9 pushes the reinforcement rod 11 until it is inserted into the soil; 5) The mouth of the steel tube 3 is sealed, and mortar is poured into the mouth of the steel tube 3. The mortar is injected into different areas from the steel tube 3 through the pouring holes 901, and then injected into the surrounding soil through the grouting channel 12 on the reinforcement plug rod 11 to form a mortar consolidation body, thereby completing the reinforcement of the culvert top soil.

[0034] Correction principle: In the above steps, in step 2), when the angle of the wedge drill bit 7 is lower than the designed trajectory angle, the wedge drill bit 7 is turned to face the inclined surface downward, and the rotation is stopped and the drill bit is directly pushed forward. The wedge drill bit 7 has an upward movement tendency due to the reaction force of the soil layer, and the drilling angle changes upward to achieve the purpose of deviation correction, until the angle reaches the design requirement and then continues to rotate and move forward; The deviation in each direction is corrected by the above method.

[0035] Drilling principle: Combined with step 3), after the original stratum debris is mixed with the mud, it flows out from the gap between the wall of the steel flower pipe 3 and the soil until it flows to the orifice, and the shed pipe continues to move forward in this cycle.

[0036] Embodiment 3: On the basis of Example 2, the joint of the steel flower pipe 3 is connected by internal and external threads, with a thread depth of 1.5mm, a pitch of 3mm, a thread length of 60mm, a right-hand thread for tightness, and a flat inner and outer wall at the connection. The length of a single pipe is 2.5m (4.12m) for the front drill pipe section, 4.12m for the middle pipe section, and 4.24m (2.62m) for the tail pipe section. The adjacent pipe shed steel pipe joints should be staggered, so that the joint of the pipe mouth of the same section can be less than 50% of the overall pipe shed.

[0037] Embodiment 4: Based on step 3) in Example 2: During the drilling process, the prepared mud liquid is pressed into the steel tube 3 by the mud pump. The mud in the steel tube 3 enters the gap between the steel tube 3 and the hole through the two spray holes 16 at the head. In addition to balancing the soil pressure in the hole, it also takes out the mud residue in the hole and returns to the mud pool at the drilling end, forming a mud cycle. The mud parameters are as follows: ① Mud density: The mass of mud per unit volume is called mud density, and the unit of mud density is g / cm³.

[0038] The size of mud density γ mainly depends on the content of solid phase (clay, rock powder, weighting agent) in the mud.

[0039] The density of mud should be adjusted according to different formations, and mud with lower density should be used as much as possible in normal drilling. The density of mud commonly used in engineering geological drilling is generally controlled in the range of 1.03-1.20g / cm³.

[0040] ② Mud solid content: The percentage of useful (clay) and useless (rock powder, sediment) solid (body) particles contained in the mud to the total amount of mud (mostly volume ratio, less mass ratio) is called mud solid content. The lower the mud solid content, the better. Low solid mud requires a solid content of less than 4%.

[0041] ③ Mud viscosity: Mud viscosity refers to the internal friction between liquid molecules, solid particles and liquid-solid phases when the mud flows. It is an indicator of the difficulty of mud flow. The viscosity has a great influence on drilling, dust removal, keeping the bottom of the hole clean and safe construction. The viscosity of mud for engineering drilling is generally expressed by funnel viscosity and is controlled within the range of 18 to 30 seconds.

[0042] In addition, the construction sequence of the steel flower pipe 3 is as follows: First, the steel pipe 3 on the top of the box culvert 1 is drilled, and then the steel pipes 3 on both sides are drilled. In order to reduce the impact on the road surface, the pipes are drilled alternately, and adjacent holes cannot be constructed continuously. This can avoid the occurrence of flushing liquid through holes and incomplete grouting during the drilling process. The middle holes are drilled before the injected cement slurry is completely solidified to avoid the adverse phenomenon of local cement lumps that affect the drilling accuracy or even make drilling impossible.

[0043] After the steel pipe 3 is installed to form a pipe shed and accepted, cement slurry is injected through the steel pipe 3 (the hole pipe 8 is cleaned and sealed before the cement slurry is poured), and mortar is injected into the soil to form a consolidated body, while the gap between the shed pipe and the hole wall is sealed.

[0044] Calculate the injection volume in advance, and the injection volume should not be less than 1.2 times the calculated injection volume. Rinse the borehole thoroughly to keep the hole evenly filled with slurry and minimize the residual drilling debris in the hole.

[0045] The grouting slurry adopts plain cement slurry, which has good pourability, slow sedimentation and water separation, good permeability, good affinity with general soil layers, and can easily form overall structural performance with surrounding soil layers and shed pipes.

[0046] The grouting ratio is 1:0.8 after field tests, and the grouting pressure of the grouting machine is controlled at an initial pressure of 0.5-1.0MPa and a final pressure of 2.0MPa. Grouting requires stable, smooth, uninterrupted, and continuous grouting. After the cement slurry comes out of the hole, the hole is sealed, and then pressurized grouting is performed 1-2 times (pressure is less than 0.3MPa). Expansion agents can be added to the cement slurry to ensure that the slurry fills the inside and outside of the pipe fully after solidification (it can also be used to fill the gap with expansion bags (expansion bags are selected to contain highly absorbent polymer particles, which can expand rapidly when exposed to water). When paying attention to the mortar, the water absorption and expansion characteristics of the expansion bags are used to further increase the extrusion force to enhance the stability of the entire support system).

Claims

1. An ultra-thin culvert top soil support construction structure, comprising a frame bridge composed of a door frame column (4) and a door frame beam (5), wherein a box culvert guide roller (6) is provided on the door frame beam (5) for guiding the box culvert (1) when it is pushed forward, characterized in that: Steel flower pipes (3) are driven into the three sides of the frame bridge to form a pipe shed, thereby supporting the ultra-thin covering soil on the upper part of the box culvert (1); A hole cleaning pipe (8) is arranged inside the steel flower pipe (3), a plurality of reinforcing rods (11) perpendicular to the axis of the hole cleaning pipe (8) are evenly distributed on the side wall of the steel flower pipe (3), and a plurality of variable-diameter top blocks (9) are arranged outside the hole cleaning pipe (8); The hole cleaning pipe (8) is pushed in along the axial direction of the steel flower pipe (3), so that the variable diameter push block (9) pushes the reinforcement plug rod (11) to expand outwards and be inserted into the foundation.

2. The ultra-thin culvert top soil covering support construction structure according to claim 1 is characterized in that: A wedge-shaped drill bit (7) is provided on the drilling end of the steel flower tube (3), and the wedge-shaped drill bit (7) is connected to an on-site display screen (15) via a wire; A wire connecting the wedge-shaped drill bit (7) and the display screen (15) is arranged through the hole cleaning pipe (8).

3. The ultra-thin culvert top soil covering support construction structure according to claim 2 is characterized in that: The hole cleaning tube (8) is open at both ends, and two channels are provided in the hole cleaning tube (8), namely a liquid through hole (801) and a wire through hole (802); A spray hole (16) is provided on the side wall of one end of the steel flower tube (3) close to the wedge-shaped drill bit (7).

4. The ultra-thin culvert top soil covering support construction structure according to claim 1 is characterized in that: The variable diameter top block (9) comprises a cylindrical section and a truncated cone section, the diameter of the cylindrical section is the same as the inner diameter of the hole cleaning pipe (8), and the diameter of the narrow end of the truncated cone section is the same as the outer diameter of the hole cleaning pipe (8); The variable diameter top block (9) is provided with a plurality of injection holes (901) distributed in an annular direction and extending from the end surface of the cylindrical section at one end to the arc surface of the truncated cone section.

5. The ultra-thin culvert top soil covering support construction structure according to claim 1 is characterized in that: A guide tube (10) is provided on the side wall of the steel flower tube (3), and a reinforcement rod (11) is inserted into the guide tube (10); The end of the reinforcing rod (11) located inside the steel flower tube (3) is a slope (112), the slope (112) contacts the reducer top block (9), and the end located outside the steel flower tube (3) is a cone head (113); The reinforcing rod (11) is provided with a grouting channel (12) extending from the inclined surface (112) to the cone head (113) inside.

6. The ultra-thin culvert top soil covering support construction structure according to claim 5 is characterized in that: A limiting tooth (1001) is provided at the end of the guide cylinder (10), and a vertical strip-shaped limiting groove (111) is provided on the side wall of the reinforcing plug rod (11). The limiting tooth (1001) cooperates with the limiting groove (111) to achieve axial limiting of the reinforcing plug rod (11).

7. The ultra-thin culvert top soil covering support construction structure according to claim 5, characterized in that: The conical head (113) of the reinforcing plug rod (11) is provided with a plurality of side slurry outlet holes (13) located on the conical surface, and the conical top of the conical head (113) is provided with an end slurry outlet hole (14); The grouting channel (12) is connected to the side grouting hole (13) and the end grouting hole (14).

8. The ultra-thin culvert top soil covering support construction structure according to claim 1, characterized in that: A blocking block (17) is provided on one end of the hole cleaning pipe (8) located inside the steel flower pipe (3); the diameter of the blocking block (17) is the same as the inner diameter of the steel flower pipe (3).

9. The ultra-thin culvert top soil covering support construction structure according to claim 8, characterized in that: During the drilling process of the steel flower pipe (3), the cleaning fluid is injected through the liquid hole (801) in the hole cleaning pipe (8), and is injected into the supporting borehole (2) through the injection hole (901) and the spray hole (16) on the variable diameter top block (9), thereby achieving hole cleaning; After the hole cleaning pipe (8) is advanced, the consolidation mortar is injected from the steel flower pipe (3), and injected into the soil around the supporting borehole (2) through the steel flower pipe (3) and the injection holes (901) on the variable diameter top block (9), and simultaneously flows into the hole through the injection holes (901) on the variable diameter top block (9) to the area where the next variable diameter top block (9) is located.

10. A construction method for an ultra-thin culvert top soil covering support construction structure according to any one of claims 1 to 9, characterized in that The following steps are involved: 1) Using the steel flower tube (3) as a drill rod, drive it along the guide tube on the door frame column (4) and the door frame beam (5); 2) the steel pipe (3) is driven in rotation, and during the driving process, the pitch angle and direction of the wedge-shaped drill bit (7) are monitored in real time through a display screen (15), and the drilling direction of the steel pipe (3) is adjusted according to the pitch angle and direction of the wedge-shaped drill bit (7); 3) During the drilling process, mud is continuously pumped into the hole cleaning pipe (8) by a mud pump, and the mud is ejected from the spray hole (16) at high pressure to cut the soil. The wedge-shaped drill bit (7) performs repairable cutting on the soil during the rotation and jacking process, thereby forming a support borehole (2) having a diameter larger than that of the steel flower pipe (3); 4) After the jacking construction is completed, the hole cleaning pipe (8) is jacked in along the axial direction of the steel flower pipe (3) so that the variable-diameter jacking block (9) pushes the reinforcing rod (11) until it is inserted into the soil; 5) sealing the mouth of the steel tube (3) and pouring mortar into the mouth of the steel tube (3); the mortar is injected into different areas from the steel tube (3) through the pouring holes (901), and then injected into the surrounding soil through the grouting channels (12) on the reinforcement rods (11), thereby forming a mortar consolidation body and completing the reinforcement of the soil covering the culvert top; In the step 2), when the angle of the wedge drill bit (7) is lower than the designed trajectory angle, the wedge drill bit (7) is turned to face the inclined surface downward, at which time the rotation is stopped and the drill bit is directly pushed forward. The wedge drill bit (7) generates an upward movement tendency due to the reaction force of the soil layer, and the drilling angle changes upward, achieving the purpose of deviation correction, until the angle reaches the designed requirement and then continues to rotate and move forward; The deviation in each direction is corrected by the above method; In the step 3), the original stratum slag is mixed with the mud and flows out from the gap between the steel pipe (3) wall and the soil until it flows to the orifice, and the shed pipe continues to move forward in this cycle.

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