阅读说明：本技术 一种地下人行通道施工方法 (Underground pedestrian passageway construction method ) 是由 葛铁金 陈坤 龙广庆 邓彬彬 潘文志 于 2021-09-01 设计创作，主要内容包括：本发明公开了一种地下人行通道施工方法,本申请通过在钢管内设置螺旋钻杆,当将钢管打入土层时,螺旋钻杆的钻头先张开然后将土层破碎,从而使得螺旋钻杆的钻出的孔洞能够让钢管顺利插入,同时,钻孔过程中所产生的土渣被螺旋钻杆运出,实现边顶进、边切削、边排土,显著提高了钢管的施工效率。当钢管施工完毕后,螺旋钻杆的钻头再闭合以便将螺旋钻杆从钢管内取出,再往钢管内灌注水泥浆液以加固地下通道施工面周边土层,以使得后续开挖过程中路面土层不易坍塌,具有提高施工安全的效果。(The invention discloses a construction method of underground pedestrian passageways, which is characterized in that an auger stem is arranged in a steel pipe, when the steel pipe is driven into a soil layer, a drill bit of the auger stem is firstly opened and then the soil layer is crushed, so that a drilled hole of the auger stem can enable the steel pipe to be smoothly inserted, meanwhile, soil slag generated in the drilling process is conveyed out by the auger stem, jacking, cutting and soil discharging are realized, and the construction efficiency of the steel pipe is obviously improved. After the steel pipe construction finishes, auger stem's drill bit is closed again so that take out auger stem from the steel pipe, pours cement thick liquid into the steel pipe again in order to consolidate the peripheral soil layer of underground passage construction face to make the difficult effect that collapses of road surface soil layer among the follow-up excavation process, have the improvement construction safety.)

1. A construction method of underground pedestrian passageways is characterized by comprising the following steps: the method comprises the following steps:

s1, excavating vertical working wells in insensitive areas at two ends of an underground passage to be constructed, wherein one of the vertical working wells is used as a starting well, and the other vertical working well is used as a receiving well;

s2, primarily excavating an underground passage prototype on the side wall of the starting well close to the receiving well, wherein the excavation depth is 0.5m, and arranging a guide steel frame (1) with the shape matched with the shape of the section of the underground passage in the primarily excavated underground passage;

s3, using a jacking device and a guide steel frame (1) to drive a plurality of steel pipes (3) and peripheral soil layers of an underground passage to be constructed in sequence to form an arched pipe curtain; specifically, a spiral drill rod (4) is arranged in the steel pipe (3), and the spiral drill rod (4) moves and rotates relative to the steel pipe (3) under the action of a jacking device;

s4, after the pipe curtain is formed, welding and fixing the steel pipe (3) and the guide steel frame (1), and then taking out the spiral drill rod (4) from the steel pipe (3); binding geotextile at the opening end of the steel pipe (3), and spraying cement slurry on the construction surface of the underground passage by using a concrete sprayer;

s5, forming a plurality of pouring holes communicated with the interior of the steel pipe (3) on the peripheral wall of the steel pipe (3), detaching the geotextile, injecting cement slurry into the steel pipe (3) by using a grouting machine, stopping grouting after the single-hole grouting pressure reaches a design required value, and plugging the steel pipe (3);

s6, when the strength of the cement slurry meets the design requirement, excavating the construction surface by using a heading machine, and conveying the crushed stone blocks and the crushed mud blocks out of the tunnel;

s7, after the excavation depth of the heading machine reaches the length of the steel pipe (3), installing a steel support inside the underground passage, paving a reinforcing mesh on the wall of the tunnel, and spraying concrete on the reinforcing mesh by using a concrete sprayer to form a primary support;

s8, after the primary support is completely stressed, constructing a tunnel waterproof layer;

s9, after the waterproof layer is constructed, using a lining trolley to construct an arch wall lining for secondary reinforcement;

and S10, excavating the second section of underground through groove, and repeating S3-S9 until the construction of the underground passage is completed.

2. The underground walkway construction method of claim 1, wherein: in the step S3, when the steel pipe (3) is driven into the soil layer by the jacking device, one end of the steel pipe (3) driven into the soil layer is pushed forward in the direction far away from the axis of the underground passage, and the included angle between the axis of the steel pipe (3) and the axis of the underground passage is 5-10 degrees.

3. The underground walkway construction method of claim 1, wherein: the steel pipe (3) is formed by splicing a plurality of pipe sections, and two adjacent pipe sections are in threaded connection; the auger stem (4) comprises a drill bit (41), a soil breaking section (42), a connecting section (43) and a plurality of connecting sections (44), the two adjacent connecting sections (44) are in threaded connection, the drill bit (41) is arranged on the soil breaking section (42), the connecting section (43) is used for connecting the soil breaking section (42) with the connecting sections (44), and after the connecting section (43) is connected with the soil breaking section (42) and the connecting sections (44), helical blades on the soil breaking section (42), the connecting section (43) and the connecting sections (44) are connected; when two adjacent sections of connecting sections (44) are connected, the helical blades on the two adjacent sections of connecting sections (44) are connected.

4. A method of underground walkway construction according to claim 3, wherein: the jacking device comprises a scissor fork mechanism (6) and a guide half pipe (7) installed on the scissor fork mechanism (6), a hydraulic oil cylinder (8) and a movable plate (9) are installed on the guide half pipe (7), a piston rod of the hydraulic oil cylinder (8) is fixedly connected with the movable plate (9), a motor (10) is installed on the movable plate (9), an output shaft of the motor (10) is detachably connected with a spiral drill rod (4), a plurality of top plates (14) are fixedly connected with the movable plate (9), and the top plates (14) are used for pushing the steel pipe (3) to move.

5. The underground walkway construction method of claim 4, wherein: the drill bit (41) can be opened and closed, and a control mechanism (15) for driving the drill bit (41) to open and close is arranged in the soil breaking section (42).

6. The underground walkway construction method of claim 5, wherein: drill bit (41) include polylith arc (411), every arc (411) all with broken ground section (42) torsional spring articulated, the equal protruding lug (412) that is equipped with of lateral wall of every arc (411), one side that lug (412) deviates from broken ground section (42) is the sawtooth surface, when drill bit (41) opened, the sawtooth surface of lug (412) is perpendicular with the axis of broken ground section (42), and the one end that arc (411) were kept away from in lug (412) flushes with the outer wall of steel pipe (3).

7. The underground walkway construction method of claim 6, wherein: the control mechanism (15) comprises an ejector rod (151) arranged in the soil breaking section (42), a fixed disc (152), a connecting rod (153), a movable disc (154) and a movable rod (155), the fixed disc (152) is fixedly connected with the soil breaking section (42), the movable disc (154) is slidably connected with the soil breaking section (42), the fixed disc (152) is positioned between the drill bit (41) and the movable disc (154), one side of the movable disc (154), which is close to the fixed disc (152), is fixedly connected with a positioning rod (156), and the fixed disc (152) is provided with a positioning hole (157) for the positioning rod (156) to be inserted; the ejector rod (151) is positioned between the fixed disc (152) and the drill bit (41) and is in sliding connection with the ground breaking section (42), and a spring (158) is fixedly connected between the ejector rod (151) and the fixed disc (152); the one end and the coaxial fixed connection of ejector pin (151) of connecting rod (153), the other end of connecting rod (153) passes fixed disk (152) and with activity dish (154) fixed connection, one side fixed connection of fixed disk (152) is kept away from with activity dish (154) to the one end of activity pole (155), the other end of activity pole (155) is worn out and is broken ground section (42) and with linking up section (43) threaded connection.

8. The underground walkway construction method of claim 7, wherein: the output shaft fixedly connected with connecting seat (11) of motor (10), linkage segment (44) are provided with that the one end of internal screw thread is sunken to have a plurality of jacks (13), many inserted bars (12) of one side fixedly connected with that connecting seat (11) deviate from the pivot, inserted bar (12) and jack (13) slip grafting that corresponds.

Technical Field

The invention relates to the technical field of tunnel excavation engineering, in particular to a construction method of an underground pedestrian passageway.

Background

The subway is an indispensable part of urban traffic, and carries important tasks of urban pedestrian traveling. In the construction process of the subway station, a plurality of entrances and exits are usually required to be arranged so that pedestrians can enter and exit the subway station. Due to factors such as road surface construction, the entrance and exit of the subway station usually have a certain distance from the subway riding point. Therefore, in the process of building the subway station, an underground pedestrian passageway penetrating through the subway entrance and exit and the subway seating point needs to be built.

At present, the construction method for underground passage generally includes open cut method, shallow buried underground cut method and shield method. The open cut method needs to excavate the original road surface, and has great influence on traffic. The distance between the subway station entrance and the subway station exit and the riding point is generally short, and the construction cost is too high by adopting a shield method, so that the underground excavation method is often adopted for construction.

The shallow-buried underground excavation method is a comprehensive matched construction technology which is used for reinforcing surrounding rocks by means of an advanced pipe shed, pre-grouting and the like, fully utilizing self-bearing capacity of the surrounding rocks, timely carrying out primary support (anchor-shotcrete net, steel frame and the like) after excavation, closing the ring as soon as possible, and then utilizing a lining trolley to construct an arch wall lining so that the arch wall lining and the surrounding rocks jointly act to form a combined enclosure system and effectively inhibit deformation and even collapse of the surrounding rocks. However, in the actual construction process, the construction process of the advanced pipe shed is low in efficiency, the construction is difficult, and an improvement space exists.

Disclosure of Invention

In order to improve the construction efficiency of the advanced pipe shed, the application provides an underground pedestrian passageway construction method.

The construction method for the underground pedestrian passageway adopts the following technical scheme: the method comprises the following steps:

s1, excavating vertical working wells in insensitive areas at two ends of an underground passage to be constructed, wherein one of the vertical working wells is used as a starting well, and the other vertical working well is used as a receiving well;

s2, primarily excavating an underground passage prototype on the side wall of the starting well close to the receiving well, wherein the excavation depth is 0.5m, and arranging a guide steel frame with the shape matched with the section shape of the underground passage in the primarily excavated underground passage;

s3, using a jacking device and a guide steel frame to drive a plurality of steel pipes and peripheral soil layers of the underground passage to be constructed in sequence to form an arched pipe curtain; specifically, a spiral drill rod is arranged in the steel pipe, and the spiral drill rod moves and rotates relative to the steel pipe under the action of the jacking device;

s4, after the pipe curtain is formed, welding and fixing the steel pipe and the guide steel frame, and taking out the spiral drill rod from the steel pipe; binding geotextile at the opening end of the steel pipe, and spraying cement slurry on the construction surface of the underground passage by using a concrete sprayer;

s5, forming a plurality of pouring holes communicated with the interior of the steel pipe on the peripheral wall of the steel pipe, detaching the geotextile, injecting cement slurry into the steel pipe by using a grouting machine, stopping grouting after the single-hole grouting pressure reaches a design required value, and plugging the steel pipe;

s6, when the strength of the cement slurry meets the design requirement, excavating the construction surface by using a heading machine, and conveying the crushed stone blocks and the crushed mud blocks out of the tunnel;

s7, after the excavation depth of the heading machine reaches the length of the steel pipe, installing steel supports in the underground passage, paving a reinforcing mesh on the wall of the tunnel, and spraying concrete on the reinforcing mesh by using a concrete sprayer to form a primary support;

s8, after the primary support is completely stressed, constructing a tunnel waterproof layer;

s9, after the waterproof layer is constructed, using a lining trolley to construct an arch wall lining for secondary reinforcement;

and S10, excavating the second section of underground through groove, and repeating S3-S9 until the construction of the underground passage is completed.

By adopting the technical scheme, the guide steel frame plays a guide role in the steel pipe and the spiral drill rod, so that the embedding position of the steel pipe meets the design requirement. And in the process of driving the steel pipe into the soil layer, the spiral drill rod rotates while being jacked under the action of the jacking device, so that the soil body is cut obliquely, and the steel pipe is more smooth in the jacking process. The soil slag generated after being cut by the spiral drill rod falls into the steel pipe and is conveyed out of the steel pipe under the pushing of the spiral blade on the spiral drill rod, so that the effects of jacking, cutting and slag discharging are realized, the jacking speed of the steel pipe is greatly improved, and the construction efficiency of the steel pipe is improved. After the pipe curtain shaping, recycle the slip casting machine and pour into the cement thick liquid to the steel pipe in, the cement thick liquid spreads to the peripheral soil horizon of steel pipe under the high pressure effect in to consolidate the peripheral soil horizon of underground passage construction face, cooperation pipe curtain self is the domes setting, so that follow-up excavation in-process road surface soil horizon is difficult for collapsing, and then improves construction safety.

Preferably, in S3 step, when utilizing the jacking device to squeeze into the steel pipe into the soil layer, make the steel pipe squeeze into the one end of soil layer and prop forward towards the direction of keeping away from the underground passage axis, the contained angle between the axis of steel pipe and the axis of underground passage is 5 ~ 10.

By adopting the technical scheme, the quantity of the cement slurry diffused to the soil layer on the periphery of the underground passage construction surface is increased, the quantity of the cement slurry diffused to the soil layer on the underground passage construction surface is reduced, the effect of solidifying the soil layer on the periphery of the underground passage construction surface is achieved, and the follow-up excavation of the underground passage is not influenced.

Preferably, the steel pipe is formed by splicing a plurality of pipe sections, and two adjacent pipe sections are in threaded connection; the spiral drill rod comprises a drill bit, a soil breaking section, a connecting section and a plurality of connecting sections, wherein the adjacent two connecting sections are in threaded connection, the drill bit is arranged on the soil breaking section, the connecting section is used for connecting the soil breaking section with the connecting section, and after the connecting section is connected with the soil breaking section and the connecting section, spiral blades on the soil breaking section, the connecting section and the connecting section are connected; when the two adjacent connecting sections are connected, the helical blades on the two adjacent connecting sections are connected.

By adopting the technical scheme, the steel pipe and the spiral drill rod are jacked in a segmented mode, the requirements for construction environment and construction space are reduced, and therefore the construction efficiency of the steel pipe is improved. And the pipe joints forming the steel pipe are connected through threads, and the adjacent connecting sections forming the spiral drill rod are connected through threads, so that the steel pipe and the spiral drill rod can be conveniently spliced.

Preferably, the jacking device comprises a scissor fork mechanism and a guide half pipe arranged on the scissor fork mechanism, a hydraulic oil cylinder and a movable plate are arranged on the guide half pipe, a piston rod of the hydraulic oil cylinder is fixedly connected with the movable plate, a motor is arranged on the movable plate, an output shaft of the motor is detachably connected with the auger stem, a plurality of top plates are fixedly connected with the movable plate, and the top plates are used for pushing the steel pipe to move.

Through adopting above-mentioned technical scheme, when the jacking steel pipe, be connected the output shaft of motor with the auger stem that has spliced, the motor operation is in order to order about auger stem and rotate, and hydraulic cylinder orders about the fly leaf antedisplacement, and the auger stem cuts the soil body in the jacking simultaneously, and the roof promotes the steel pipe at the in-process of antedisplacement and progressively jacks in, breaks open the soil body because of auger stem is prior to the steel pipe to make things convenient for the steel pipe jacking. And the mud formed by the soil body crushed by the drill falls into the steel pipe and is discharged from the tail end of the steel pipe under the action of the helical blade, so that the operation of frequently discharging mud is omitted, and the jacking speed of the steel pipe is further accelerated.

Preferably, the drill bit can open and shut and set up, be provided with the control mechanism that control drill bit opened and shut in the section of breaking ground.

Through adopting above-mentioned technical scheme, when drilling, utilize control mechanism to open the drill bit to the drilling that makes the drill bit bore out can hold the steel pipe, so that the steel pipe can insert in the drilling more smoothly. After the steel pipe is jacked to a set depth, the drill bit is closed through the control mechanism, and therefore the spiral ejector rod can be conveniently taken out of the steel pipe.

Preferably, the drill bit includes the polylith arc, every the arc all is articulated with the section torsional spring that breaks ground, and the equal protruding lug that is equipped with of lateral wall of every arc, one side that the lug deviates from the section that breaks ground is the serrated surface, and when the drill bit opened, the serrated surface of lug is perpendicular with the axis of the section that breaks ground, and the one end that the arc was kept away from to the lug flushes with the outer wall of steel pipe.

Through adopting above-mentioned technical scheme, when the drill bit receives the foreign object extrusion, the polylith arc can open, and at this moment, the one end that the arc was kept away from to the lug flushes with the outer wall of steel pipe, and one side that the lug deviates from the section of breaking ground is the sawtooth surface to make the drilling that the drill bit drilled out can supply the steel pipe to pass through, in order to accelerate the speed of advancing in top of steel pipe. And when the drilling depth reaches the total length of the steel pipe, the drill bit is closed through the control mechanism, and the auger stem can be taken out of the steel pipe.

Preferably, the control mechanism comprises an ejector rod, a fixed disc, a connecting rod, a movable disc and a movable rod which are arranged in the soil breaking section, the fixed disc is fixedly connected with the soil breaking section, the movable disc is slidably connected with the soil breaking section, the fixed disc is positioned between the drill bit and the movable disc, one side of the movable disc, which is close to the fixed disc, is fixedly connected with a positioning rod, and the fixed disc is provided with a positioning hole for the positioning rod to be inserted; the ejector rod is positioned between the fixed disc and the drill bit and is in sliding connection with the ground breaking section, and a spring is fixedly connected between the ejector rod and the fixed disc; the one end and the coaxial fixed connection of ejector pin of connecting rod, the other end of connecting rod pass the fixed disk and with activity dish fixed connection, one side fixed connection of fixed disk is kept away from with the activity dish to the one end of movable rod, the other end of movable rod wear out the section of breaking ground and with link up section threaded connection.

Through adopting above-mentioned technical scheme, after the movable rod is connected with the linking section, be connected motor and linking section, hydraulic cylinder promotes the fly leaf antedisplacement, and the linking section drives the movable rod antedisplacement, and the movable rod antedisplacement drives the movable disc antedisplacement, and the locating lever that is located on the movable disc inserts in the locating hole at the antedisplacement in-process, and the movable disc antedisplacement drives the connecting rod antedisplacement, thereby the connecting rod antedisplacement drives the ejector pin antedisplacement and struts the drill bit, and the spring is in tensile state this moment. The motor operation orders about linking section and rotates to drive movable rod and activity dish to rotate, the activity dish passes through the locating lever and drives the fixed disk rotation, and the fixed disk rotates and drives broken section and drill bit and rotate, thereby makes the drill bit realize advancing, the soil body is cut simultaneously to the top speed that improves the steel pipe. After the steel pipe is pushed in, with motor and auger stem split, the ejector pin no longer receives external force to drive to separate with the drill bit under the effect of spring, polylith arc then folds under the effect of torsional spring separately, thereby conveniently takes out auger stem from the steel pipe.

Preferably, the output shaft fixedly connected with connecting seat of motor, the many inserted bars of one side fixedly connected with that the connecting seat deviates from the pivot, the linking section is close to the one end of linkage segment the linkage segment is provided with the equal sunken a plurality of jacks that have of internal screw thread one end, inserted bar and the jack that corresponds slip the grafting.

Through adopting above-mentioned technical scheme, after linking section or linkage segment were placed on the half pipe of direction, hydraulic cylinder promoted the fly leaf antedisplacement in order to drive the motor antedisplacement, and the inserted bar that is located on the connecting seat inserts in the plug hole that is located linking section or linkage segment at the antedisplacement in-process to can drive the auger stem rotation after making the motor operation.

Drawings

FIG. 1 is a schematic structural view of a steel pipe buried after preliminary excavation of an underground tunnel in the present application;

FIG. 2 is a schematic structural view of a steel pipe construction in the present application;

FIG. 3 is a schematic structural view of the jacking device in the present application when jacking a steel pipe;

FIG. 4 is a schematic view of the internal structure of the steel pipe of the present application;

FIG. 5 is a schematic structural view of the auger stem of the present application;

FIG. 6 is an enlarged schematic view of A of FIG. 5 of the present application;

fig. 7 is a schematic view of the drill bit of the present application after deployment.

Description of reference numerals:

1. a guide steel frame; 2. locking the anchor rod; 3. a steel pipe; 31. a head pipe section; 32. a middle pipe section; 33. a tail pipe section; 4. a auger stem; 41. a drill bit; 411. an arc-shaped plate; 412. a bump; 42. a soil breaking section; 43. a joining section; 44. a connecting section; 5. a slurry stop valve; 6. a scissor mechanism; 7. a guiding half pipe; 8. a hydraulic cylinder; 9. a movable plate; 10. a motor; 11. a connecting seat; 12. inserting a rod; 13. a jack; 14. a top plate; 15. a control mechanism; 151. a top rod; 152. fixing the disc; 153. a connecting rod; 154. a movable tray; 155. a movable rod; 156. positioning a rod; 157. positioning holes; 158. a spring.

Detailed Description

The present application is described in further detail below with reference to figures 1-7.

The embodiment of the application discloses a construction method of an underground pedestrian passageway. The method comprises the following steps:

s1, excavating vertical working wells in insensitive areas at two ends of the underground passage to be constructed, wherein one of the vertical working wells is used as a starting well, and the other vertical working well is used as a receiving well.

S2, primarily excavating an underground passage prototype on the side wall of the starting well close to the receiving well, wherein the excavation depth is 0.5m, and arranging the guide steel frame 1 with the shape matched with the section shape of the underground passage in the primarily excavated underground passage.

Specifically, the guiding steel frame 1 is formed by butt-jointing two steel bars which are arranged in an arc-shaped bending manner. When installation direction steelframe 1, arrange lock foot stock 2 in 1 both sides of direction steelframe, in the lateral wall soil horizon of the underground passage of hammering into preliminary excavation downwards with the slope of lock foot stock 2, the inclination of lock foot stock 2 is 30 ~ 45. And then cement grout is poured into the foot-locking anchor rod 2 to strengthen the connection strength between the foot-locking anchor rod 2 and the soil layer. And then, welding the foot locking anchor rod 2 and the guide steel frame 1 together through the U-shaped steel bar, and finishing the installation of the guide steel frame 1.

S3, sequentially driving a plurality of steel pipes 3 into the peripheral soil layers of the underground passage to be constructed by using the jacking device and the guide steel frame 1 to form an arched pipe curtain; and make the one end that steel pipe 3 was beaten into the soil layer advance toward keeping away from the direction of underground passage axis, the contained angle between the axis of steel pipe 3 and the axis of underground passage is 5 ~ 10.

Specifically, the guide steel frame 1 is provided with a plurality of guide holes along the length direction for the steel pipes 3 to pass through, the steel pipes 3 are inserted into the soil layer after passing through the guide holes, and the guide steel frame 1 plays a guiding role in the steel pipes 3 so that the steel pipes 3 cannot deviate when being driven into the soil layer.

The steel pipe 3 is formed by splicing a plurality of pipe joints, the pipe joints are a head pipe joint 31, a middle pipe joint 32 and a tail pipe joint 33 which are connected in sequence, and the middle pipe joint 32 is provided with a plurality of pipes. The head pipe joint 31 is in threaded connection with the middle pipe joint 32, the middle pipe joints 32 of the two adjacent sections are in threaded connection, the tail pipe joint 33 is in threaded connection with the middle pipe joint 32, the tail pipe joint 33 is used for being externally connected with the slurry stop valve 5, and the slurry stop valve 5 is a ball valve.

An auger stem 4 is arranged in the steel pipe 3, and the auger stem 4 can move and rotate relative to the steel pipe 3 under the action of the jacking device. Specifically, the auger stem 4 includes a drill 41, a ground breaking section 42, a joining section 43, and a connecting section 44, which are connected in sequence, wherein the connecting section 44 is provided with a plurality of sections. The drill bit 41 is arranged in a taper shape, the drill bit 41 is arranged at one end of the ground breaking section 42, the connecting section 43 is used for connecting the ground breaking section 42 with the connecting section 44, the connecting section 43 is in threaded connection with the connecting section 44, and two adjacent sections of the connecting sections 44 are in threaded connection. When the soil breaking section 42 is connected with the connecting section 43 and the connecting section 44, the helical blades on the soil breaking section 42, the connecting section 43 and the connecting section 44 are connected; when two adjacent connecting sections 44 are connected, the helical blades on the two adjacent connecting sections 44 are engaged.

The jacking device comprises a scissor mechanism 6 and a guide half pipe 7 arranged on the scissor mechanism 6, a hydraulic oil cylinder 8 and a movable plate 9 are arranged in the guide half pipe 7, the cylinder body of the hydraulic oil cylinder 8 is fixedly connected with the guide half pipe 7, and the piston rod of the hydraulic oil cylinder 8 is fixedly connected with the movable plate 9.

And a motor 10 for driving the auger stem 4 to rotate is arranged on one side of the movable plate 9, which is far away from the hydraulic oil cylinder 8, and an output shaft of the motor 10 is coaxially arranged with the guide half pipe 7. The output shaft fixedly connected with connecting seat 11 of motor 10, connecting seat 11 are circular setting, and the external diameter of the diameter auger stem 4 of connecting seat 11 equals. One side fixedly connected with a plurality of inserted bars 12 that motor 10 was kept away from to connecting seat 11, a plurality of inserted bars 12 circumference distribute at the edge of connecting seat 11, and the one end that linking section 43 and linkage segment 44 are connected, linkage segment 44 are provided with the one end of internal thread and all set up the jack 13 that supplies inserted bar 12 to insert.

One side of the movable plate 9, which is far away from the hydraulic oil cylinder 8, is fixedly connected with three top plates 14, the three top plates 14 are circumferentially distributed on the top plates 14, and the top plates 14 are used for pushing the steel pipes 3 to move.

The drill bit 41 can be opened and closed, and the control mechanism 15 for controlling the opening and closing of the drill bit 41 is arranged in the soil breaking section 42. Specifically, the drill 41 includes a plurality of arc plates 411, and four arc plates 411 are provided in the embodiment of the present application. Every arc 411 all is articulated with the section of breaking ground 42 torsional spring, and the lateral wall of every arc 411 all is protruding to be equipped with lug 412, and one side that lug 412 deviates from the section of breaking ground 42 is the sawtooth surface, and when drill bit 41 opened, the sawtooth surface of lug 412 was perpendicular with the axis of the section of breaking ground 42, and the one end that arc 411 was kept away from to lug 412 flushes with the outer wall of steel pipe 3. So that the hole drilled by the drill 41 can allow the steel pipe 3 to pass smoothly, thereby increasing the jacking speed of the steel pipe 3.

The control mechanism 15 includes a top rod 151, a fixed disk 152, a connecting rod 153, a movable disk 154, and a movable rod 155 provided in the ground-breaking section 42. The fixed disc 152 is fixedly connected with the soil breaking section 42, the movable disc 154 is slidably connected with the soil breaking section 42, the fixed disc 152 is located between the drill bit 41 and the movable disc 154, one side of the movable disc 154, which is close to the fixed disc 152, is fixedly connected with a positioning rod 156, a positioning hole 157 for the positioning rod 156 to insert is formed in the fixed disc 152, and the positioning rod 156 is in inserting fit with the positioning hole 157. The push rod 151 is located between the fixed disk 152 and the drill bit 41 and is connected with the soil breaking section 42 in a sliding manner, one end of the push rod 151 is arranged in a taper shape and is used for expanding the drill bit 41, and a spring 158 is fixedly connected between the other end of the push rod 151 and the fixed disk 152. The diameter of the connecting rod 153 is smaller than that of the push rod 151, one end of the connecting rod 153 is coaxially and fixedly connected with the push rod 151, the other end of the connecting rod 153 penetrates through the fixed disc 152 and is fixedly connected with the movable disc 154, and the connecting rod 153 is slidably connected with the fixed disc 152. One end of the movable rod 155 is fixedly connected with one side of the movable disc 154 far away from the fixed disc 152, and the other end of the movable rod 155 penetrates through the soil breaking section 42 and is in threaded connection with the connecting section 43.

Specifically, when the steel pipe 3 is driven into the ground in stages by the jack-in device, the ground-breaking segment 42 is inserted into the head pipe section 31 and the drill 41 is caused to protrude out of the head pipe section 31. Then the connecting section 43 is in threaded connection with the movable rod 155, the middle pipe joint 32 and the head pipe joint 31 are in threaded connection and are placed on the guide half pipe 7 together, the guide half pipe 7 is conveyed to a steel pipe 3 embedding point with a specified height by the scissor fork mechanism 6, and the steel pipe 3 is inserted into the corresponding guide hole. The hydraulic cylinder 8 pushes the movable plate 9 to move forward, the insertion rod 12 is inserted into the insertion hole 13 of the engagement section 43 during the forward movement, and then the movable rod 155 follows the forward movement of the engagement section 43 and drives the movable plate 154 to move toward the direction close to the fixed plate 152, and the positioning rod 156 is inserted into the positioning hole 157 during the forward movement. The connecting rod 153 follows the movable disk 154 forward causing the ram 151 to spread the drill bit 41 open, with the spring 158 in tension and the top plate 14 just abutting the middle tube section 32.

Then, the hydraulic oil cylinder 8 continues to push the steel pipe 3 and the auger stem 4 to advance, the motor 10 operates to drive the connecting section 43 to rotate, the connecting section 43 drives the fixed disc 152 to rotate through the movable rod 155 and the movable disc 154, the fixed disc 152 rotates to drive the soil breaking section 42 to rotate, and the drill 41 rotates along with the soil breaking section 42 to break soil, so that the steel pipe 3 is driven into the soil layer more smoothly. Meanwhile, the soil slag generated by the drill bit 41 in the drilling process can automatically fall into the steel pipe 3, and is conveyed out of the steel pipe 3 and falls into the guide half pipe 7 under the pushing of the helical blades, a soil discharge port is formed in the bottom of the guide half pipe 7 and is formed along the length direction of the guide half pipe 7, and the soil slag falling into the guide half pipe 7 automatically falls into an underground passage for excavation through the soil discharge port. Thereby realizing the simultaneous jacking, cutting and slag discharging and obviously improving the jacking speed of the steel pipe 3.

After the head pipe joint 31 and the ground breaking section 42 are driven into the soil layer, the following pipe joints and the connecting section 44 are jacked in a subsection mode through the jacking device, and therefore construction of one steel pipe 3 is completed.

S4, after the pipe curtain is formed, welding and fixing the steel pipe 3 and the guide steel frame 1, and then taking out the spiral drill rod 4 from the steel pipe 3; and binding geotextile at the opening end of the steel pipe 3, and spraying cement slurry on the construction surface of the underground passage by using a concrete sprayer.

Specifically, after the insertion rod 12 is withdrawn from the insertion hole 13, the ejector rod 151 is no longer subjected to external force, so as to be reset under the action of the spring 158, after the ejector rod 151 is separated from the drill bit 41, the plurality of arc plates 411 are folded under the action of respective torsion springs, and the auger rod 4 can be taken out of the steel pipe 3 by pulling the auger rod 4.

And S5, removing the geotextile after the cement grout sprayed on the underground passage construction surface is solidified, injecting the cement grout into the steel pipe 3 by using a grouting machine, wherein the grouting is performed from bottom to top in sequence, and the grouting is stopped and the steel pipe 3 is blocked after the single-hole grouting pressure reaches the design required value.

Specifically, the peripheral walls of the head pipe joint 31 and the middle pipe joint 32 which form the steel pipe 3 are provided with a plurality of pouring holes communicated with the inside of the steel pipe 3, and the peripheral wall of the tail pipe joint 33 which forms the steel pipe 3 is closed. And (3) installing the grout stop valve 5 on the tail pipe joint 33, connecting a grouting pipe of a grouting machine with the grout stop valve 5, injecting cement grout into the steel pipe 3 by the grouting machine, and stopping grouting and plugging the steel pipe 3 when the single-hole grouting pressure reaches a designed required value.

And S6, when the strength of the cement slurry meets the design requirement, excavating the construction surface by using a heading machine, and conveying the crushed stone blocks and the crushed mud blocks out of the tunnel.

And S7, after the excavation depth of the heading machine reaches the length of the steel pipe 3, installing a steel support in the underground passage, paving a reinforcing mesh on the wall of the tunnel, and spraying concrete on the reinforcing mesh by using a concrete spraying machine to form primary support.

And S8, after the primary support is completely stressed, constructing a tunnel waterproof layer.

And S9, after the waterproof layer is constructed, using the lining trolley to construct an arch wall lining for secondary reinforcement.

And S10, excavating the second section of underground through groove, and repeating S3-S9 until the receiving well is penetrated, thereby completing the construction of the underground passage.

The implementation principle of the underground pedestrian passageway construction method in the embodiment of the application is as follows:

before underground tunnel excavation is carried out, steel pipe 3 construction is firstly carried out in the peripheral soil layer of the underground tunnel construction surface to form an arched pipe curtain, in the construction process of the steel pipe 3, the steel pipe 3 is driven into the soil layer in a segmented mode by utilizing a jacking device, jacking, cutting and slag discharging are simultaneously carried out in the construction process, and therefore the construction efficiency of the steel pipe 3 is obviously improved. And then, cement slurry is poured into the steel pipe 3 by using a grouting machine, and the cement slurry is diffused into the soil layer around the steel pipe 3 under the action of high pressure, so that the soil layer around the section of the tunnel is reinforced, and the construction of the subsequent soil layer excavation is safe.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.